ABC Certified Prosthetic Technician (CTP) — Questions and Answers

Question 1: What is the correct procedure for adjusting the tension on a flexible drive shaft used with rotary carving tools in a prosthetic lab?

Lubricate externally with grease and increase speed
Follow the manufacturer's specification and avoid kinking the shaft (Correct answer)
Replace the shaft if any flex is felt during use
Increase tension until vibration stops

Correct answer: Follow the manufacturer's specification and avoid kinking the shaft

Flexible drive shafts must be set per manufacturer's tension spec and kept free of kinks, which cause wear and shaft failure.

Question 2: A patient with a transtibial prosthesis reports a foul odor from the socket liner after several months of use. The MOST appropriate recommendation is:

Prescribe a secondary liner to alternate and reduce odor
Replace the liner if odor persists after thorough cleaning per manufacturer guidelines (Correct answer)
Apply antibacterial spray inside the socket daily
Instruct the patient to air-dry the liner without washing

Correct answer: Replace the liner if odor persists after thorough cleaning per manufacturer guidelines

If proper cleaning does not eliminate odor, the liner material has likely absorbed microbial contamination and degraded, warranting replacement.

Question 3: Under HIPAA, which type of information requires the strictest protection in a prosthetics practice?

Manufacturer warranty documentation
Billing codes used for reimbursement
Technician training records
Protected Health Information (PHI) (Correct answer)

Correct answer: Protected Health Information (PHI)

HIPAA's Privacy and Security Rules mandate strict safeguards for Protected Health Information (PHI), which includes any identifiable patient health data.

Question 4: When a prosthetic component is replaced under warranty, which documentation is still required?

A patient complaint letter
A duplicate of the original delivery receipt
Only the warranty claim form from the manufacturer
A new prescription and updated medical necessity documentation (Correct answer)

Correct answer: A new prescription and updated medical necessity documentation

Even warranty replacements require updated documentation including a new or reaffirmed prescription and evidence of continued medical necessity.

Question 5: Which scenario represents an appropriate use of a patient's PHI for 'treatment purposes' under HIPAA?

Sharing fitting notes with the referring physician coordinating care (Correct answer)
Emailing a patient's diagnosis to their employer at the employer's request
Posting a de-identified case study on social media
Discussing patient details with staff who are not involved in care

Correct answer: Sharing fitting notes with the referring physician coordinating care

Sharing PHI with other treating providers for care coordination is a permitted treatment use under HIPAA.

Question 6: When fabricating a check socket for a new amputee, what is the primary purpose of using a transparent material?

To assess skin contact and pressure distribution visually (Correct answer)
To test the durability of the socket design
To improve patient psychological acceptance
To reduce fabrication costs

Correct answer: To assess skin contact and pressure distribution visually

Transparent check sockets allow the clinician to visually assess areas of contact, air gaps, and pressure distribution while the patient is weight-bearing.

Question 7: Which action by a prosthetic technician would constitute patient abandonment?

Terminating care without adequate notice or transition planning while the patient still needs treatment (Correct answer)
Referring a patient to a specialist for complex fitting needs
Taking a scheduled vacation with coverage arranged in advance
Documenting that a patient missed two consecutive appointments

Correct answer: Terminating care without adequate notice or transition planning while the patient still needs treatment

Patient abandonment occurs when a provider unilaterally ends a therapeutic relationship without proper notice or ensuring continuity of care.

Question 8: When using a pull-through lamination technique, the stockinette layers are arranged so that:

Carbon fiber is placed directly against the positive model
Outermost cosmetic stocking is applied first
All layers run parallel to the socket brim
Innermost nylon is pulled through last after all reinforcement layers (Correct answer)

Correct answer: Innermost nylon is pulled through last after all reinforcement layers

In pull-through lamination, the inner nylon stockinette is pulled through the carbon and fiberglass layers last to create a smooth inner socket surface.

Question 9: Which anatomical plane divides the body into anterior and posterior halves, and is used to describe A-P socket dimensions in prosthetics?

Oblique plane
Transverse plane
Frontal (coronal) plane (Correct answer)
Sagittal plane

Correct answer: Frontal (coronal) plane

The frontal (coronal) plane divides the body into front and back halves, and anteroposterior (A-P) socket measurements reference this plane.

Question 10: A prosthetics technician discovers that a batch of laminated sockets has delamination defects. Under a quality management system, the first required action is to:

Quarantine and tag the nonconforming product to prevent use (Correct answer)
Bill for devices as completed and rework them later
Immediately dispose of all sockets and reorder materials
Deliver devices and note the defect in the patient file

Correct answer: Quarantine and tag the nonconforming product to prevent use

Nonconforming products must be identified, segregated, and tagged to prevent unintended use, as required by quality management standards such as ISO 13485.

Question 11: During residual limb assessment, a prosthetist notes a positive Tinel's sign at the distal end. This finding most likely indicates:

Neuroma formation requiring further evaluation (Correct answer)
Optimal bony contouring
Adequate skin integrity for prosthetic fitting
Normal scar tissue maturation

Correct answer: Neuroma formation requiring further evaluation

A positive Tinel's sign (tingling elicited by percussion) at the residual limb tip indicates neuroma formation, which can cause pain with prosthetic use.

Question 12: What is the primary reason for applying a silicone release agent to a positive plaster model before thermoplastic draping?

To accelerate thermoplastic cooling
To reduce friction during model modification
To prevent the thermoplastic from bonding to the plaster model (Correct answer)
To improve surface texture of the socket interior

Correct answer: To prevent the thermoplastic from bonding to the plaster model

Release agent prevents the heated thermoplastic from adhering to the plaster positive model, allowing clean removal after the material cools.

Question 13: Which muscle group is primarily responsible for knee extension?

Gluteals
Quadriceps (Correct answer)
Hamstrings
Gastrocnemius

Correct answer: Quadriceps

The quadriceps femoris is a large muscle group located on the front of the thigh, consisting of four individual muscles. Its primary function is to extend the knee joint, straightening the leg, which is essential for activities like standing, walking, running, and jumping.

Question 14: How does understanding tissue healing phases improve practice?

It has no effect on treatment outcomes
It is relevant only in hospital settings
It guides appropriate treatment timing and technique selection (Correct answer)
It only matters for surgical wounds

Correct answer: It guides appropriate treatment timing and technique selection

Understanding healing phases allows practitioners to select appropriate timing and techniques for each stage, optimizing recovery and preventing re-injury.

Question 15: Which classification does the FDA assign to most custom-fabricated prosthetic limbs?

Class II (Special Controls) (Correct answer)
Class IV (Investigational Device)
Class I (General Controls)
Class III (Premarket Approval)

Correct answer: Class II (Special Controls)

Most prosthetic limbs are classified as Class II medical devices, subject to special controls and typically requiring 510(k) clearance for new products.

Question 16: What does the term 'sharps container fill line' indicate in a prosthetics lab context?

The fill line is only relevant in medical settings, not prosthetics labs
The container should be closed and replaced when waste reaches this line (Correct answer)
The container can hold 25% more after this line
The container must be weighed when this line is reached

Correct answer: The container should be closed and replaced when waste reaches this line

Sharps containers should be sealed and replaced when waste reaches the indicated fill line to prevent overfilling and needle-stick injuries.

Question 17: Under the Americans with Disabilities Act (ADA), a prosthetics practice must ensure which of the following for patients with mobility impairments?

Free device upgrades annually
Physical accessibility of the facility (Correct answer)
Reduced billing rates for disabled patients
Priority scheduling over non-disabled patients

Correct answer: Physical accessibility of the facility

The ADA requires places of public accommodation, including healthcare facilities, to provide physical accessibility to individuals with disabilities.

Question 18: For a dysvascular amputee returning for a follow-up fitting visit, which assessment should be performed FIRST before any socket modifications?

Measurement of prosthetic alignment
Evaluation of prosthetic foot rollover
Inspection of the residual limb skin integrity (Correct answer)
Gait analysis on parallel bars

Correct answer: Inspection of the residual limb skin integrity

Dysvascular patients are at high risk for pressure injuries, so skin integrity inspection must be performed first to detect any early signs of breakdown before stressing the tissue further.

Question 19: The 'four-bar linkage' knee mechanism in a prosthesis offers which primary biomechanical advantage?

Generates energy storage and return like a carbon fiber spring
Provides active powered extension during swing
Creates a polycentric instantaneous center of rotation, improving stability in early stance (Correct answer)
Locks automatically at any angle selected by the user

Correct answer: Creates a polycentric instantaneous center of rotation, improving stability in early stance

The polycentric (four-bar) knee moves its instantaneous center of rotation posteriorly in early stance, increasing inherent stability without full weight.

Question 20: Which lamination resin type offers the highest strength-to-weight ratio for prosthetic sockets?

Epoxy resin (Correct answer)
Polyester resin
Acrylic resin
Urethane resin

Correct answer: Epoxy resin

Epoxy resin provides the highest strength-to-weight ratio among lamination resins commonly used in prosthetic socket fabrication.

Question 21: When documenting alignment adjustments during a dynamic gait analysis, the technician should record:

The total cost of components adjusted
The patient's subjective comfort rating only
Specific measurements and the rationale for each change (Correct answer)
Only the final alignment position

Correct answer: Specific measurements and the rationale for each change

Documentation of alignment adjustments must include specific measurement data and clinical rationale to support the prosthetic intervention.

Question 22: Which document must a prosthetics supplier have on file to demonstrate that a Medicare patient's device was medically necessary?

Patient's personal insurance card copy
Certificate of Medical Necessity (CMN) or detailed written order (Correct answer)
Technician's fabrication worksheet
Manufacturer's product brochure

Correct answer: Certificate of Medical Necessity (CMN) or detailed written order

Medicare requires a Certificate of Medical Necessity or detailed written order from the treating physician to support medical necessity for prosthetic devices.

Question 23: Which regulation governs proper disposal of sharp objects such as drills and saw blades used in prosthetic fabrication?

OSHA Bloodborne Pathogen Standard for sharps disposal (Correct answer)
EPA hazardous waste regulations only
FDA device disposal guidelines
State health department food-service codes

Correct answer: OSHA Bloodborne Pathogen Standard for sharps disposal

OSHA's Bloodborne Pathogen Standard requires proper sharps disposal containers and procedures to protect workers from percutaneous injury.

Question 24: The principle of nonmaleficence in prosthetics specifically requires the technician to:

Ensure equal resource distribution among all patients
Avoid actions or omissions that cause harm to the patient (Correct answer)
Respect patient decisions regardless of consequences
Promote patient independence at all costs

Correct answer: Avoid actions or omissions that cause harm to the patient

Nonmaleficence — 'first, do no harm' — obliges clinicians to avoid causing harm through action or inaction.

Question 25: A colleague asks the prosthetic technician to falsify a fitting date on a patient's record to meet an insurance deadline. The correct response is to:

Change the date only if it does not affect patient care
Comply if the colleague is a supervisor
Refuse and report the request to the compliance officer (Correct answer)
Discuss with the patient to obtain retroactive permission

Correct answer: Refuse and report the request to the compliance officer

Falsifying medical records is fraudulent and unethical; the technician must refuse and report the request through proper channels.

Question 26: Under HIPAA, a prosthetic technician shares a patient's fitting details with a colleague not involved in the patient's care. This is:

Required for accreditation audits
Allowed if the colleague is credentialed
Permitted for quality improvement purposes
A violation of the minimum necessary standard (Correct answer)

Correct answer: A violation of the minimum necessary standard

HIPAA's minimum necessary standard prohibits sharing PHI with individuals not involved in the patient's direct care without proper authorization.

Question 27: Which of the following best describes a 'delivery confirmation' document in prosthetics?

An internal memo approving the order
A payer's authorization letter
A shipping manifest from the component manufacturer
A signed form confirming the patient received the device (Correct answer)

Correct answer: A signed form confirming the patient received the device

A delivery confirmation is a patient-signed document verifying that the prosthetic device was received, which is required for Medicare billing.

Question 28: Which thermoset resin system is most often used for definitive prosthetic socket lamination due to its low shrinkage and high strength?

Epoxy resin (Correct answer)
Vinyl ester resin
Polyester resin
Phenolic resin

Correct answer: Epoxy resin

Epoxy resin offers low cure shrinkage, excellent mechanical properties, and strong adhesion to reinforcing fibers, making it the preferred choice for definitive sockets.

Question 29: When reviewing a transtibial definitive socket prior to delivery, which area of the residual limb should ALWAYS have a prominent relief to avoid pressure-related skin breakdown?

Anterior tibial crest and distal tibia
Both fibular head and anterior tibial crest / distal tibia (Correct answer)
Fibular head and distal fibula
Posterior calf muscle belly

Correct answer: Both fibular head and anterior tibial crest / distal tibia

Both the fibular head and the anterior tibial crest/distal tibia are bony prominences that require relief areas in a transtibial socket to prevent pressure sores.

Question 30: Which tool is most commonly used by a prosthetic technician to verify the angular alignment of a prosthetic foot relative to the socket?

Alignment jig or alignment device (Correct answer)
Tape measure
Torque wrench
Caliper

Correct answer: Alignment jig or alignment device

An alignment jig or dedicated alignment device allows the technician to accurately set and verify the angular relationship between the socket and prosthetic foot.

Question 31: A technician notices that a co-worker has been entering fabrication times that appear inflated. The correct response is to:

Ignore it as it is not the technician's responsibility
Report the concern through the facility's compliance process (Correct answer)
Correct the entries without informing anyone
Adjust the technician's own records to match

Correct answer: Report the concern through the facility's compliance process

Suspected fraudulent documentation must be reported through the facility's compliance or ethics reporting process to protect the patient and organization.

Question 32: State licensure laws for prosthetic technicians primarily serve which regulatory function?

Setting Medicare reimbursement rates
Mandating specific material suppliers
Approving new device designs for commercial sale
Establishing minimum competency and scope-of-practice standards (Correct answer)

Correct answer: Establishing minimum competency and scope-of-practice standards

State licensure laws define minimum competency requirements and scope-of-practice boundaries to protect public safety.

Question 33: When documenting residual limb shape for socket design, a 'dog-eared' appearance refers to:

Scar contracture pulling skin toward the bone
Redundant soft tissue folds at the distal end or corners of the closure (Correct answer)
Adequate conical shaping of the residual limb
Excessive bony prominence at the fibular head

Correct answer: Redundant soft tissue folds at the distal end or corners of the closure

Dog-ears are redundant tissue folds often seen at surgical closure corners; they create fitting challenges and pressure concentration in the prosthetic socket.

Question 34: When should a practitioner modify their assessment approach?

Only when requested by the patient
Never, standardized protocols must always be followed exactly
When the patient presents with contraindications or special needs (Correct answer)
After completing all standard tests regardless of findings

Correct answer: When the patient presents with contraindications or special needs

Assessment approaches should be modified when patients present with contraindications or special needs to ensure safety and obtain the most relevant diagnostic information.

Question 35: Which factor most commonly leads to delamination failure in a carbon fiber prosthetic foot shell?

Sanding with too fine a grit
Incorrect laminate ratio of resin to reinforcement (Correct answer)
Applying too many stockinette layers
Using a heat gun too far from the surface

Correct answer: Incorrect laminate ratio of resin to reinforcement

An incorrect resin-to-reinforcement ratio leaves voids or resin-rich zones that are prone to delamination under load.

Question 36: Which thermoforming temperature range is typically used for low-temperature thermoplastics (LTTPs) used in check socket fabrication?

450–500°F (232–260°C)
250–300°F (121–149°C)
350–400°F (177–204°C)
150–180°F (65–82°C) (Correct answer)

Correct answer: 150–180°F (65–82°C)

Low-temperature thermoplastics soften and become formable between approximately 150–180°F, allowing safe draping directly over a plaster model or the patient.

Question 37: Which piece of documentation is used to justify the upgrade from a basic SACH foot to an energy-storing foot for a K3 patient?

A letter from the patient's family requesting the upgrade
Functional goals statement and documented activity level consistent with K3 (Correct answer)
Patient's age and employment history
Prior use of a SACH foot for more than one year

Correct answer: Functional goals statement and documented activity level consistent with K3

A documented functional goals statement aligned with a K3 activity level provides the clinical justification for prescribing an energy-storing foot.

Question 38: Which standard specifically governs the mechanical testing of lower-limb prostheses to verify structural integrity?

ASTM F1821
ANSI Z87.1
ISO 10328 (Correct answer)
IEC 60601

Correct answer: ISO 10328

ISO 10328 specifies structural testing procedures for lower-limb prostheses, including static and cyclic load tests to verify durability.

Question 39: What should be done if an error is discovered in existing records?

Draw a single line through the error, note the correction, date, and initial (Correct answer)
Remove the page and rewrite it
Ignore the error if it seems minor
Use correction fluid to cover the error

Correct answer: Draw a single line through the error, note the correction, date, and initial

The correct method is a single line through the error with a dated and initialed correction, preserving the original entry for legal and audit purposes.

Question 40: What is the primary purpose of applying a release agent to a positive mold before lamination?

To prevent the lamination from permanently bonding to the mold (Correct answer)
To accelerate the curing process
To improve resin penetration into the fiber layers
To add color to the finished socket

Correct answer: To prevent the lamination from permanently bonding to the mold

Release agents create a barrier between the mold surface and the laminate, allowing clean separation after curing without damaging either.

Question 41: Which component connects the prosthetic socket to the foot in a lower limb prosthesis?

Cushion liner
Foot shell
Pylon (Correct answer)
Strap

Correct answer: Pylon

The pylon is the structural component that connects the prosthetic socket, which encases the residual limb, to the prosthetic foot. It acts as the "shin" or "leg" of the prosthesis, providing support, transmitting forces, and often incorporating features for height adjustment and shock absorption.

Question 42: A transfemoral prosthesis with a silicone liner and locking pin system fails to lock consistently. After confirming the pin is undamaged, the technician should next inspect:

The pylon rotation lock for misalignment
The suspension sleeve for tears
The locking shuttle mechanism inside the socket for debris or wear (Correct answer)
The proximal brim trim line for pressure sores

Correct answer: The locking shuttle mechanism inside the socket for debris or wear

If the pin is intact, inconsistent locking points to debris accumulation or wear in the shuttle lock mechanism inside the socket distal end.

Question 43: When transitioning between treatment phases, what is essential?

Let the patient decide all treatment parameters
Continue the same approach indefinitely
Make changes without updating records
Document the rationale for change and update goals accordingly (Correct answer)

Correct answer: Document the rationale for change and update goals accordingly

Documenting the rationale for treatment phase changes and updating goals ensures continuity of care, clear communication, and appropriate progress tracking.

Question 44: Which fastener type is preferred when attaching metal components to carbon fiber sockets to prevent galvanic corrosion?

Titanium or stainless steel fasteners with isolating washers (Correct answer)
Standard carbon steel bolts
Aluminum rivets
Zinc-plated steel screws

Correct answer: Titanium or stainless steel fasteners with isolating washers

Titanium or stainless steel fasteners with isolating washers prevent galvanic corrosion at the dissimilar metal interface with carbon fiber.

Question 45: When assessing cognition in a potential prosthetic candidate, the clinical team is primarily concerned with whether the patient can:

Perform complex mathematical calculations
Demonstrate pre-amputation vocational skills
Learn and safely execute a donning/doffing routine and recognize skin warning signs (Correct answer)
Complete standardized IQ testing

Correct answer: Learn and safely execute a donning/doffing routine and recognize skin warning signs

Successful prosthetic use requires sufficient cognition to learn the donning/doffing procedure, maintain a wearing schedule, and recognize skin problems requiring socket removal.

Question 46: A prosthetic technician notices a crack in their nitrile glove mid-procedure. What is the correct action?

Apply tape over the crack to seal it
Continue working and change gloves at the end of the task
Double-glove over the cracked glove immediately
Stop, remove gloves, perform hand hygiene, and don new gloves (Correct answer)

Correct answer: Stop, remove gloves, perform hand hygiene, and don new gloves

A compromised glove barrier must be replaced immediately; the technician must remove the gloves, perform hand hygiene, and don a new pair.

Question 47: A patient's prosthetic foot exhibits excessive medial whip during swing phase. Which modification would BEST correct this problem?

Rotate the foot internally in the pylon
Increase dorsiflexion resistance in the foot
Lower the heel height of the prosthetic foot
Rotate the foot externally in the pylon (Correct answer)

Correct answer: Rotate the foot externally in the pylon

Medial whip is caused by internal rotation of the prosthetic foot; rotating the foot externally in the pylon corrects the whip by neutralizing the rotational alignment.

Question 48: Which quality assurance document must be completed and retained in the patient's file when a prosthetic component is replaced under warranty?

A new prescription signed by the referring physician
Only the manufacturer's warranty claim form
A written repair note documenting the defective component, replacement part number, and date of service (Correct answer)
A patient satisfaction survey confirming the repair resolved the issue

Correct answer: A written repair note documenting the defective component, replacement part number, and date of service

A detailed written repair note with part numbers and dates must be retained for compliance, billing audit trails, and future clinical reference regardless of warranty status.

Question 49: Which component is used between a transtibial socket and a prosthetic foot to provide a cosmetically acceptable leg shape while protecting internal components?

Suspension sleeve
Liner with locking pin
Exoskeletal (crustacean) shell
Endoskeletal pylon with foam cover (Correct answer)

Correct answer: Endoskeletal pylon with foam cover

An endoskeletal pylon covered with a shaped foam cover provides both structural support and cosmetic appearance in a modular transtibial prosthesis.

Question 50: In the context of residual limb vascular assessment, which vessel is the primary arterial supply to the lower extremity?

Anterior tibial artery
Popliteal artery
Femoral artery (Correct answer)
Posterior tibial artery

Correct answer: Femoral artery

The femoral artery is the main arterial supply to the lower extremity, originating from the external iliac artery.

Question 51: An otto bock-style pyramid adapter (four-hole pyramid) serves what primary purpose in a modular prosthetic system?

It allows rotational and angular adjustment between the pylon and foot/knee component (Correct answer)
It connects the socket trim line to the liner
It houses the hydraulic fluid reservoir
It provides the suction valve port for suspension

Correct answer: It allows rotational and angular adjustment between the pylon and foot/knee component

A pyramid adapter provides a standardized interface with adjustable alignment capability between the pylon and distal components, enabling fine-tuning of foot/knee orientation.

Question 52: Which infection control tier applies when a patient's infection status is unknown?

Standard precautions (Correct answer)
Airborne precautions
No precautions needed unless symptoms are visible
Transmission-based precautions only

Correct answer: Standard precautions

Standard precautions are applied to ALL patients regardless of known infection status, treating all blood and body fluids as potentially infectious.

Question 53: When fabricating a supracondylar suspension transtibial socket (SC/SP), the medial and lateral trim lines must be:

Below the femoral condyles to avoid bony prominences
Even with the patellar tendon bar
At the level of the fibular head
Above the femoral condyles to capture them for suspension (Correct answer)

Correct answer: Above the femoral condyles to capture them for suspension

The SC/SP design achieves suspension by extending the socket trim lines above the femoral condyles, locking the socket onto the condyles.

Question 54: What is the purpose of a prosthetic liner (e.g., silicone, urethane, or thermoplastic elastomer liner)?

Seals the socket from moisture ingress only
Reinforces the structural rigidity of the socket
Provides cushioning, suspension, and skin protection for the residual limb (Correct answer)
Adds weight to match the contralateral limb

Correct answer: Provides cushioning, suspension, and skin protection for the residual limb

Prosthetic liners serve multiple functions including cushioning, skin protection, and often provide the primary or secondary suspension mechanism for the prosthesis.

Question 55: A prosthetic technician notices the oven used for thermoplastic forming is heating unevenly across the chamber. What is the most likely cause?

Failed or misaligned heating element (Correct answer)
Incorrect plastic material selection
Excessive chamber humidity
Incorrect thermostat setting

Correct answer: Failed or misaligned heating element

Uneven heat distribution in a lab oven typically indicates a burned-out or misaligned heating element that must be replaced.

Question 56: Which suspension system for a transtibial prosthesis requires the least amount of residual limb volume stability to function effectively?

Simple sleeve suspension
Locking liner pin system
Elevated vacuum suspension (Correct answer)
Supracondylar suspension with wedge

Correct answer: Elevated vacuum suspension

Elevated vacuum suspension actively compensates for volume fluctuation by maintaining negative pressure within the socket, making it most tolerant of volume changes.

Question 57: Which suspension method for a transtibial prosthesis relies on a urethane or silicone liner rolled onto the residual limb, with a locking pin that engages a clutch mechanism in the socket?

Elevated vacuum suspension (EVS)
Pin/lock (lanyard) suspension (Correct answer)
Supracondylar cuff suspension
Suction suspension with one-way valve

Correct answer: Pin/lock (lanyard) suspension

Pin/lock suspension uses a distal locking pin on the liner that clicks into a clutch or shuttle lock built into the distal socket, providing reliable mechanical suspension.

Question 58: Which material is most commonly used for creating a rigid prosthetic socket?

Epoxy resin (Correct answer)
Polyethylene
Polypropylene
Silicone

Correct answer: Epoxy resin

Epoxy resin is commonly used for creating rigid prosthetic sockets due to its excellent strength-to-weight ratio, durability, and ability to be molded precisely. It provides the necessary structural integrity and stiffness to support the patient's limb and transfer forces effectively during ambulation.

Question 59: What is the functional significance of setting appropriate initial flexion in a transtibial socket?

Promotes smooth knee flexion and quadriceps activation during loading (Correct answer)
Increases stride length on the prosthetic side
Reduces energy cost during quiet standing only
Decreases pylon length requirements

Correct answer: Promotes smooth knee flexion and quadriceps activation during loading

Initial socket flexion in a transtibial prosthesis facilitates loading response mechanics and activates residual limb musculature appropriately during gait.

Question 60: Which standard does the FDA reference for testing the biocompatibility of materials used in direct skin contact prosthetic components?

ASTM F2213
ANSI/AAMI ES60601
ISO 13485
ISO 10993 (Correct answer)

Correct answer: ISO 10993

ISO 10993 provides a framework for evaluating the biological safety of medical device materials, including skin-contact prosthetic components.

Question 61: Which anatomical structure forms the roof of the carpal tunnel and is relevant when fitting upper-limb prostheses to prevent median nerve compression?

Extensor retinaculum
Palmar aponeurosis
Annular pulley A1
Flexor retinaculum (transverse carpal ligament) (Correct answer)

Correct answer: Flexor retinaculum (transverse carpal ligament)

The flexor retinaculum forms the roof of the carpal tunnel; its compression on the median nerve causes carpal tunnel syndrome.

Question 62: Before laminating a prosthetic socket, what preparation must be performed on the test socket or positive mold surface?

Heat the mold to 200°F
Sand to a rough texture for adhesion
Wet the surface with water
Apply a release agent or PVA film to allow removal (Correct answer)

Correct answer: Apply a release agent or PVA film to allow removal

A release agent or PVA film is applied to prevent the laminate from permanently bonding to the mold.

Question 63: What should be done immediately after a needlestick injury?

Wait to see if symptoms develop
Wash the area, report the incident, and seek medical evaluation (Correct answer)
Document it at the end of the shift
Apply a bandage and continue working

Correct answer: Wash the area, report the incident, and seek medical evaluation

Immediate wound care, incident reporting, and medical evaluation are essential after needlestick injuries to minimize infection risk and ensure proper follow-up.

Question 64: A vacuum-forming machine fails to achieve the target vacuum level. Which component should be checked first?

The heating element thermostat
The plastic sheet thickness
The vacuum pump oil level and intake filter (Correct answer)
The frame clamp tension

Correct answer: The vacuum pump oil level and intake filter

Low vacuum is most often caused by a dirty intake filter or low pump oil, both of which reduce pump efficiency.

Question 65: In upper-limb prosthetics, a body-powered hook terminal device is typically activated by which harness motion?

Shoulder depression
Elbow flexion
Wrist pronation
Scapular abduction (forward reach) via a figure-8 harness (Correct answer)

Correct answer: Scapular abduction (forward reach) via a figure-8 harness

Scapular abduction generated by forward reach transmits force through the control cable of a figure-8 harness to open the voluntary-opening hook.

Question 66: How often should equipment be sterilized or disinfected?

Only when visibly soiled
Once per shift
Weekly during routine maintenance
Between each patient use according to manufacturer guidelines (Correct answer)

Correct answer: Between each patient use according to manufacturer guidelines

Equipment must be sterilized or disinfected between each patient use following manufacturer guidelines to prevent cross-contamination and ensure patient safety.

Question 67: A prosthetics facility must conduct a Corrective and Preventive Action (CAPA) process when which event occurs?

Annual insurance renewal is due
A new technician is hired
A patient requests a device modification
A product defect or quality nonconformance is identified (Correct answer)

Correct answer: A product defect or quality nonconformance is identified

CAPA processes are triggered by identified defects, nonconformances, or quality failures to correct root causes and prevent recurrence.

Question 68: When a prosthetics company acquires another practice, which regulatory requirement must be addressed regarding existing Medicare supplier agreements?

The new owner automatically inherits the billing number with no action needed
The FDA must approve the ownership transfer before billing can continue
Only state licensure re-application is required
The new owner must enroll separately in PECOS and obtain a new supplier number (Correct answer)

Correct answer: The new owner must enroll separately in PECOS and obtain a new supplier number

Medicare supplier numbers and billing agreements are not automatically transferable; new owners must complete a fresh PECOS enrollment.

Question 69: Which of the following best describes total contact socket design philosophy in prosthetics?

Distributing pressure evenly over the entire residual limb surface (Correct answer)
Using a heavily padded distal end to protect the residual limb
Relying solely on proximal trim lines for load transfer
Maximizing weight-bearing on pressure-tolerant areas only

Correct answer: Distributing pressure evenly over the entire residual limb surface

Total contact socket design distributes forces across the entire residual limb surface to minimize peak pressures at any single point and improve circulation.

Question 70: When mixing acrylic lamination resin, what ratio of hardener to base resin is most commonly used?

1:1 by weight
1:5 by weight
1:20 by weight
1:10 by weight (Correct answer)

Correct answer: 1:10 by weight

Acrylic lamination resins typically use a 1:10 hardener-to-base ratio by weight, though technicians must always follow the manufacturer's specific instructions.

Question 71: A transfemoral socket exhibits a medial brim that is too high, likely causing:

Perineal pressure and adductor roll (Correct answer)
Abductor lurch during gait
Lateral trunk lean away from prosthetic side
Inadequate suspension

Correct answer: Perineal pressure and adductor roll

An overly high medial brim creates pressure against the perineum and adductor tissue, commonly called adductor roll.

Question 72: In a prosthetics lab, which waste stream requires disposal as regulated medical waste (biohazardous waste)?

Empty resin containers
Used sandpaper from finishing carbon fiber
Spent grinding wheels
Soiled casting materials with blood or body fluids (Correct answer)

Correct answer: Soiled casting materials with blood or body fluids

Casting materials contaminated with blood or body fluids meet the definition of regulated medical waste and must be disposed of per OSHA and state biohazard waste regulations.

Question 73: What should a practitioner do when regulations conflict with employer policies?

Ignore both and use personal judgment
Always follow employer policies
Follow the regulation, as legal requirements supersede employer policies (Correct answer)
Follow whichever is easier to comply with

Correct answer: Follow the regulation, as legal requirements supersede employer policies

Legal and regulatory requirements always take precedence over employer policies, and practitioners have a professional obligation to comply with applicable laws.

Question 74: To prevent galvanic corrosion between a titanium pylon and a stainless steel adapter, the technician should:

Ensure both metals are fully submerged in grease
Apply a bead of silicone sealant around the junction
Anodize both components before assembly
Use a nylon isolation washer between components (Correct answer)

Correct answer: Use a nylon isolation washer between components

A nylon or other non-conductive isolation washer breaks the electrical pathway between dissimilar metals, preventing galvanic corrosion at the interface.

Question 75: Which technique is used to assess the pressure distribution inside a prosthetic socket on a residual limb?

Visual inspection of the limb surface after donning
Performing a strength test of the socket laminate
Measuring socket circumference with a tape measure
Pressure-sensitive film or digital pressure mapping system (Correct answer)

Correct answer: Pressure-sensitive film or digital pressure mapping system

Pressure-sensitive film or digital pressure mapping systems placed between the liner and socket provide objective data on load distribution across the residual limb.

Question 76: When submitting a claim for a myoelectric upper-limb prosthesis, the supporting documentation must include:

The patient's credit score and payment history
Physician's order, functional assessment, and fitting notes (Correct answer)
Only the HCPCS code on the claim form
A photo of the completed device

Correct answer: Physician's order, functional assessment, and fitting notes

Complex devices like myoelectric prostheses require comprehensive documentation including a physician's order, documented functional need, and clinical fitting records.

Question 77: A transtibial prosthetic user reports redness and skin breakdown at the distal end of the residual limb. This most likely indicates which fitting problem?

Liner thickness too great causing heat buildup
Socket too wide causing excessive pistoning
Inadequate total contact — distal end bearing too much concentrated load (Correct answer)
Foot energy return too high for the user's activity level

Correct answer: Inadequate total contact — distal end bearing too much concentrated load

Distal end skin breakdown typically results from inadequate total contact, causing the residual limb to drop into the socket and concentrate load on the distal tip.

Question 78: A prosthetic technician develops a skin rash after repeated contact with uncured epoxy. What is the MOST appropriate corrective action?

Use nitrile gloves and barrier cream; consult occupational health (Correct answer)
Switch to a slower-curing epoxy formulation
Apply topical antibiotic and continue working
Reduce resin mixing time to limit exposure

Correct answer: Use nitrile gloves and barrier cream; consult occupational health

Epoxy sensitization requires eliminating skin contact through proper PPE; continued exposure worsens sensitization and occupational health evaluation is warranted.

Question 79: According to standard prosthetic protocols, how often should a patient with a mature, stable residual limb have their prosthesis formally evaluated by a credentialed clinician?

Every 6 months to 1 year (Correct answer)
Every month
Every 5 years
Only when a problem arises

Correct answer: Every 6 months to 1 year

Standard of care guidelines recommend formal prosthetic evaluations every 6 to 12 months for patients with stable residual limbs to ensure continued fit, function, and safety.

Question 80: Which factor is most important when determining treatment frequency?

Patient preference alone
Insurance coverage limits
Evidence-based clinical guidelines and patient response (Correct answer)
Practitioner schedule availability

Correct answer: Evidence-based clinical guidelines and patient response

Treatment frequency should be based on evidence-based clinical guidelines and individual patient response to ensure optimal outcomes.

Question 81: What is the primary goal of static alignment in lower-limb prosthetics?

Maximize walking speed on level surfaces
Reduce prosthetic weight for the patient
Achieve a stable base of support in a standing position (Correct answer)
Improve cosmetic appearance of the prosthesis

Correct answer: Achieve a stable base of support in a standing position

Static alignment establishes a stable base of support while the patient stands, before dynamic adjustments are made during walking.

Question 82: Microprocessor-controlled prosthetic knees (MPKs) use onboard sensors primarily to assess which variables in real time?

Battery voltage and Bluetooth signal strength
Patient heart rate and oxygen saturation
Angular velocity, acceleration, and load data to modulate hydraulic resistance (Correct answer)
Socket pressure and residual limb temperature only

Correct answer: Angular velocity, acceleration, and load data to modulate hydraulic resistance

MPKs use gyroscopes, accelerometers, and load cells to continuously assess limb kinematics, then adjust hydraulic or pneumatic resistance to optimize gait.

Question 83: To achieve proper pistoning control in a pin-lock suspension system, the technician must ensure:

The pin engages the locking mechanism at full knee extension only
The pin is made of carbon fiber for reduced weight
The shuttle pin length equals the liner thickness
The liner pin length matches the distal socket receiver depth (Correct answer)

Correct answer: The liner pin length matches the distal socket receiver depth

Proper fit requires the liner's pin length to match the receiver depth so the lock engages securely without bottoming out or incomplete engagement.

Question 84: During the swing phase of gait, the primary role of the hip flexors is to:

Stabilize the pelvis against gravity
Decelerate the limb before foot strike
Control knee extension at terminal swing
Advance the limb forward through hip flexion (Correct answer)

Correct answer: Advance the limb forward through hip flexion

Hip flexors (primarily iliopsoas) contract concentrically during initial swing to accelerate and advance the limb forward.

Question 85: Which lamination layup sequence provides the greatest torsional rigidity for a transfemoral socket?

Fiberglass inner with carbon fiber 0° outer
±45° carbon fiber outer with 90° inner (Correct answer)
Random-weave carbon fiber throughout
0°/0°/0° carbon fiber

Correct answer: ±45° carbon fiber outer with 90° inner

Placing carbon fiber layers at ±45° to the principal axis maximizes resistance to twisting forces encountered during ambulation.

Question 86: Which vacuum level range is recommended during diagnostic socket lamination to ensure adequate resin infusion without voids?

30–35 inHg
5–10 inHg
15–20 inHg
25–29 inHg (Correct answer)

Correct answer: 25–29 inHg

A vacuum level of 25–29 inHg (near atmospheric) ensures thorough resin wet-out and void-free lamination in prosthetic socket fabrication.

Question 87: A patient requests a copy of their prosthetic records. Under HIPAA, the facility must provide access within:

90 days
15 days
60 days
30 days (Correct answer)

Correct answer: 30 days

HIPAA requires covered entities to provide patients with access to their health records within 30 days of the request, with one 30-day extension if needed.

Question 88: The CMS Competitive Bidding Program for durable medical equipment primarily impacts prosthetics suppliers by doing which of the following?

Setting competitive reimbursement rates in selected geographic areas (Correct answer)
Mandating ABC certification for all staff
Eliminating the need for physician prescriptions
Requiring FDA 510(k) clearance for all devices

Correct answer: Setting competitive reimbursement rates in selected geographic areas

The CMS Competitive Bidding Program establishes reimbursement rates through a bidding process among eligible suppliers in designated competitive bidding areas.

Question 89: Which socket design for transtibial amputees loads the patellar tendon as a primary weight-bearing surface?

Quadrilateral socket
Ischial containment socket
Total surface bearing (TSB) socket
Patellar tendon bearing (PTB) socket (Correct answer)

Correct answer: Patellar tendon bearing (PTB) socket

The patellar tendon bearing socket concentrates load over the patellar tendon bar while relieving pressure over sensitive bony prominences of the lower leg.

Question 90: Which property of carbon fiber composites makes them preferred over aluminum for high-activity prosthetic feet?

Resistance to UV degradation
Higher energy return and lower weight (Correct answer)
Lower cost
Greater malleability

Correct answer: Higher energy return and lower weight

Carbon fiber stores and releases mechanical energy during gait while being significantly lighter than aluminum, improving functional outcomes.

Question 91: In socket design, what does the term 'relief area' refer to?

A soft liner zone over the distal residual limb
The distal end padding applied to the socket interior
A region of the socket that is relieved (expanded or softened) to reduce pressure over a bony prominence (Correct answer)
The total area of socket-residual limb contact

Correct answer: A region of the socket that is relieved (expanded or softened) to reduce pressure over a bony prominence

Relief areas are intentional modifications to the socket wall that reduce pressure over bony prominences such as the fibular head or tibial crest to prevent skin breakdown.

Question 92: Which record retention period does CMS require DMEPOS suppliers to maintain documentation supporting Medicare claims?

10 years from the date of service
5 years from the date of service or from the date of any audit, whichever is later (Correct answer)
7 years from the date of service
2 years from the date of service

Correct answer: 5 years from the date of service or from the date of any audit, whichever is later

CMS requires DMEPOS suppliers to retain claim-related documentation for a minimum of 7 years; however, the general federal requirement is 5 years and some state laws extend this further.

Question 93: A technician receives a verbal order from the prescribing physician to change the prosthetic foot category. What must happen before fabrication?

The verbal order is sufficient to proceed immediately
The technician should wait 90 days before acting
The verbal order must be followed up with a written order within the payer's required timeframe (Correct answer)
The change must be approved by the patient's insurer before the physician signs anything

Correct answer: The verbal order must be followed up with a written order within the payer's required timeframe

Verbal orders must be documented and followed up with a written or electronic signed order within the timeframe specified by the payer to be valid for billing.

Question 94: Why is it important to document the patient's informed consent before fitting a new prosthetic device?

It replaces the need for a physician's prescription
It confirms the patient understands risks, benefits, and alternatives, and is a legal and ethical requirement (Correct answer)
It is only necessary for pediatric patients
It is only required for surgical procedures, not prosthetics

Correct answer: It confirms the patient understands risks, benefits, and alternatives, and is a legal and ethical requirement

Informed consent documentation confirms the patient was educated about the device, alternatives, and potential limitations, which is both a legal requirement and an ethical standard of care.

Question 95: How should equipment cleaning products be selected?

The same product for all equipment types
Based on personal preference
Whichever product is least expensive
Based on manufacturer recommendations and material compatibility (Correct answer)

Correct answer: Based on manufacturer recommendations and material compatibility

Manufacturer recommendations ensure cleaning products are compatible with equipment materials, preventing damage while achieving effective decontamination.

Question 96: What is the correct sequence of steps when fabricating a thermoplastic transfemoral socket using direct forming?

Trim → heat plastic → drape over cast → add suspension
Heat plastic → drape over cast → trim → add suspension (Correct answer)
Add suspension → heat plastic → drape over cast → trim
Drape over cast → heat plastic → trim → add suspension

Correct answer: Heat plastic → drape over cast → trim → add suspension

The direct forming process begins with heating the thermoplastic sheet, draping it over the positive model, trimming after cooling, then adding suspension components.

Question 97: A prosthetic technician is asked by law enforcement to release a patient's records without a subpoena or court order. The correct action is to:

Refuse all disclosure and contact hospital legal counsel
Release only demographic information and withhold clinical notes
Release records immediately to cooperate with authorities
Require a valid court order, subpoena, or qualifying legal process first (Correct answer)

Correct answer: Require a valid court order, subpoena, or qualifying legal process first

HIPAA requires a court order, subpoena, or other qualifying legal authority before disclosing records to law enforcement.

Question 98: Which chemical is classified as a high-level disinfectant appropriate for semi-critical prosthetic devices that contact intact skin?

Isopropyl alcohol 50%
Quaternary ammonium compounds (quats)
Simple green soap
2% glutaraldehyde solution (Correct answer)

Correct answer: 2% glutaraldehyde solution

2% glutaraldehyde is a high-level disinfectant capable of killing most microorganisms including mycobacteria, and is appropriate for semi-critical items.

Question 99: During upper extremity prosthesis fabrication, the figure-8 harness attachment point at the axilla loop should be positioned to:

Allow full humeral flexion without excessive migration (Correct answer)
Limit elbow ROM to 90°
Maximize cosmetic appearance
Rest directly over the acromion process

Correct answer: Allow full humeral flexion without excessive migration

Correct axilla loop placement allows unrestricted humeral flexion while keeping the harness stable and preventing migration during terminal device operation.

Question 100: The 'calcaneus gait' pattern, characterized by excessive heel contact without a push-off, is most commonly caused by:

Overactive tibialis anterior muscle
Tight heel cord and equinus deformity
A prosthetic foot with too much plantar flexion
Weak plantar flexors or a prosthetic foot set in excessive dorsiflexion (Correct answer)

Correct answer: Weak plantar flexors or a prosthetic foot set in excessive dorsiflexion

Calcaneus gait results from inadequate plantar flexor strength or a prosthetic foot aligned with too much dorsiflexion, eliminating effective push-off.

Question 101: A prosthetic technician uses a torque wrench when assembling ankle-foot components primarily to:

Speed up the assembly process
Ensure fasteners are tightened to manufacturer-specified torque values (Correct answer)
Detect stripped threads before final assembly
Prevent cross-threading of fasteners

Correct answer: Ensure fasteners are tightened to manufacturer-specified torque values

Torque wrenches ensure fasteners reach the exact clamping force specified by the manufacturer, preventing both under-tightening (loosening in use) and over-tightening (component damage).

Question 102: A prosthetics facility operating in two different states must comply with which regulatory framework regarding licensure?

Each state's individual licensure laws must be satisfied separately for each location (Correct answer)
A single national license covers all states through reciprocity automatically
Only the state where corporate headquarters is registered requires licensure
Only the federal CMS standards apply across state lines

Correct answer: Each state's individual licensure laws must be satisfied separately for each location

Prosthetics licensure is state-specific, and facilities operating in multiple states must independently meet each state's licensure requirements.

Question 103: How often should a practitioner review applicable regulations and standards?

Only when notified of a violation
Regularly, as regulations are updated frequently and compliance is ongoing (Correct answer)
Every five years at renewal time
Only during initial licensure

Correct answer: Regularly, as regulations are updated frequently and compliance is ongoing

Regular review of regulations is necessary because standards evolve frequently, and maintaining current knowledge is essential for ongoing compliance.

Question 104: What is the correct order for donning personal protective equipment?

Any order is acceptable
Gloves, gown, mask, eye protection
Gown, mask, eye protection, gloves (Correct answer)
Mask, gloves, gown, eye protection

Correct answer: Gown, mask, eye protection, gloves

The correct donning sequence (gown, mask, eye protection, gloves) ensures complete coverage and prevents contamination of already-donned items.

Question 105: Which documentation practice best supports legal defensibility?

Brief notes using abbreviations
Objective, factual entries with specific measurements and timestamps (Correct answer)
Subjective opinions about client behavior
Copying previous entries to save time

Correct answer: Objective, factual entries with specific measurements and timestamps

Objective, factual entries with specific measurements and timestamps provide the strongest legal defense by demonstrating thorough, unbiased professional practice.

Question 106: Under FDA regulations, a prosthetics manufacturer who makes a significant design change to a cleared 510(k) device must generally:

Notify only the state health department of the change
Submit a new 510(k) premarket notification before marketing the modified device (Correct answer)
Obtain an IDE (Investigational Device Exemption) for the modification
Proceed with distribution and file a change report annually

Correct answer: Submit a new 510(k) premarket notification before marketing the modified device

Significant design changes that could affect safety or effectiveness require submission of a new 510(k) before the modified device can be marketed.

Question 107: Which element is required in a Certificate of Medical Necessity (CMN) for a lower-limb prosthesis?

Technician's fabrication time log
Physician's signature and date (Correct answer)
Patient's insurance premium amount
Supplier's profit margin documentation

Correct answer: Physician's signature and date

A valid CMN requires a licensed physician's signature and date to certify the medical necessity of the prosthetic device.

Question 108: When fabricating a prosthetic hand with intrinsic cables, cable housing must be secured to prevent:

Over-tightening of the wrist unit
Excessive finger extension
Cable bowstringing away from the digit axes (Correct answer)
Corrosion of the stainless cable

Correct answer: Cable bowstringing away from the digit axes

Cable housing must be anchored along the digit pathway to prevent bowstringing, which would alter mechanical advantage and reduce grip efficiency.

Question 109: What does Shore hardness measure in the context of prosthetic materials?

Flexural modulus
Thermal conductivity
Tensile strength
Resistance to permanent indentation (Correct answer)

Correct answer: Resistance to permanent indentation

Shore hardness quantifies a material's resistance to surface indentation, helping technicians select appropriate liner and padding materials.

Question 110: What is the purpose of a flexible inner socket (FIS) design in prosthetics?

To increase structural rigidity of the prosthetic socket
To eliminate the need for a suspension system
To reduce fabrication cost by using less material
To allow dynamic accommodation of residual limb volume changes during activity (Correct answer)

Correct answer: To allow dynamic accommodation of residual limb volume changes during activity

A flexible inner socket accommodates minor volume fluctuations of the residual limb during activity while a rigid outer frame maintains structural integrity.

Question 111: When building a transfemoral prosthesis with a modular system, which alignment stage involves adjusting the spatial relationship of the socket to the knee and foot components while the patient stands and walks?

Static alignment
Bench alignment
Dynamic alignment (Correct answer)
Definitive alignment

Correct answer: Dynamic alignment

Dynamic alignment is performed while the patient ambulates, allowing the prosthetist and technician to observe gait deviations and adjust component positioning for optimal function.

Question 112: Which catalyst-to-resin ratio deviation is most likely to cause a brittle, under-cured lamination?

Too little catalyst relative to resin (Correct answer)
Catalyst added before resin wetting
Too much catalyst relative to resin
Equal parts catalyst and resin

Correct answer: Too little catalyst relative to resin

Insufficient catalyst prevents full cross-linking of the resin, resulting in an under-cured, brittle laminate with reduced mechanical properties.

Question 113: When a prosthetic device is lost or stolen, what documentation action should occur first?

Wait 90 days before taking any action
Order a replacement immediately and bill insurance
Report to the police without notifying the payer
Document the incident in the patient's record and notify the payer per their guidelines (Correct answer)

Correct answer: Document the incident in the patient's record and notify the payer per their guidelines

The incident must be documented in the patient's record and the payer notified according to their specific guidelines before a replacement can be appropriately ordered and billed.

Question 114: When using a rotary tool (Dremel-type) for finishing carbon fiber prosthetic components, which bit type is most appropriate?

Standard aluminum oxide grinding stone
Wire brush attachment
Diamond-coated or carbide burr (Correct answer)
High-speed steel twist bit

Correct answer: Diamond-coated or carbide burr

Diamond-coated or carbide burr bits are required for carbon fiber because its abrasive nature dulls standard steel quickly.

Question 115: When grinding the inner surface of a laminated socket to relieve a pressure area, the technician should use:

A wire wheel attachment
A carbide router bit at high speed
A drum sander at low speed with light pressure (Correct answer)
A flap disc grinder

Correct answer: A drum sander at low speed with light pressure

A drum sander at low speed with light pressure allows controlled, gradual material removal without burning or delaminating the composite layers.

Question 116: A myoelectric prosthetic hand uses surface electromyography (sEMG) signals from residual limb muscles to control the hand. Which muscle pair is most commonly used for transradial myoelectric control?

Wrist flexors and wrist extensors (Correct answer)
Deltoid anterior and deltoid posterior
Pectoralis major and serratus anterior
Biceps brachii and triceps brachii

Correct answer: Wrist flexors and wrist extensors

The wrist flexors and wrist extensors of the residual forearm are the primary electrode sites for transradial myoelectric control, as they retain voluntary muscle function distal to the amputation.

Question 117: When applying an ace bandage (elastic wrap) to a transtibial residual limb, in which direction should wrapping begin to achieve proper shaping?

Distally and move proximally using a figure-eight pattern (Correct answer)
Circumferentially around the mid-shaft only
Proximally and move distally in circular turns
From the knee crease wrapping toward the ankle

Correct answer: Distally and move proximally using a figure-eight pattern

Elastic bandage wrapping should start distally and progress proximally using figure-eight turns to apply greater compression distally, promoting the tapered cone shape needed for socket fitting.

Question 118: What is the primary reason compressed air should be filtered and dried before use in pneumatic prosthetic lab tools?

To prevent moisture and particulates from damaging tool internals and contaminating components (Correct answer)
To comply with fire codes
To reduce noise during operation
To increase air pressure at the tool

Correct answer: To prevent moisture and particulates from damaging tool internals and contaminating components

Moisture and particulates in compressed air accelerate wear of pneumatic tool seals and can contaminate prosthetic materials being fabricated.

Question 119: Which section of a prosthetic patient record documents the patient's residual limb measurements and shape?

Delivery record
Evaluation/assessment (Correct answer)
Plan of care
Progress note

Correct answer: Evaluation/assessment

The evaluation or assessment section captures objective data including residual limb measurements, shape, skin condition, and volume.

Question 120: In electronic health records (EHR) used in prosthetics, an audit trail is important because it:

Tracks who accessed or modified records and when, supporting compliance and fraud prevention (Correct answer)
Eliminates the need for patient signatures
Converts paper records to digital format
Automatically submits claims to Medicare

Correct answer: Tracks who accessed or modified records and when, supporting compliance and fraud prevention

EHR audit trails create an immutable log of all record access and modifications, which is essential for HIPAA compliance and detecting unauthorized changes.

Question 121: A transtibial amputee exhibits 'whip' motion of the prosthetic foot during swing phase. The most likely cause is:

Insufficient socket flexion in the sagittal plane
Excessive prosthetic foot plantar flexion resistance
A prosthetic limb that is too long
Rotational malalignment of the prosthetic foot relative to the socket (Correct answer)

Correct answer: Rotational malalignment of the prosthetic foot relative to the socket

Whip motion (medial or lateral) during swing is caused by rotational malalignment between the socket and prosthetic foot, creating inward or outward flinging.

Question 122: A prosthetics facility that bills Medicare must enroll in which program to obtain a National Provider Identifier (NPI)?

FDA device registration database
State Medicaid enrollment portal
PECOS (Provider Enrollment, Chain, and Ownership System) (Correct answer)
ABC credentialing system

Correct answer: PECOS (Provider Enrollment, Chain, and Ownership System)

Medicare requires providers to enroll through PECOS and obtain an NPI before submitting claims for reimbursement.

Question 123: What is the consequence of practicing outside the defined scope of practice?

Potential license revocation, legal liability, and risk to public safety (Correct answer)
Reduced continuing education requirements
A verbal warning for first-time offenses
No consequences if the outcome is positive

Correct answer: Potential license revocation, legal liability, and risk to public safety

Practicing outside scope carries serious consequences including license revocation, legal liability, and potentially endangering the public, regardless of the outcome.

Question 124: During check socket fabrication for a transtibial amputee, the primary purpose of using clear thermoplastic is to:

Improve patient comfort immediately
Visualize tissue contact and pressure areas (Correct answer)
Permanently replace the definitive socket
Reduce fabrication time

Correct answer: Visualize tissue contact and pressure areas

Clear thermoplastic check sockets allow the clinician to observe skin blanching, tissue displacement, and contact patterns during fitting.

Question 125: Under OSHA standards, which hazard communication element must be present on all containers of hazardous chemicals used in a prosthetics lab?

Employee signature acknowledging hazard awareness
GHS-compliant label with pictograms and signal word (Correct answer)
Material Safety Data Sheet inside the container
Manufacturer's telephone number only

Correct answer: GHS-compliant label with pictograms and signal word

OSHA's Hazard Communication Standard (HazCom 2012) requires GHS-compliant labels including pictograms, signal words, and hazard statements on all hazardous chemical containers.

Question 126: Which practice best ensures technician safety in the prosthetics lab?

Use PPE and follow lab protocols (Correct answer)
Skip gloves for better grip
Avoid using PPE for better comfort
Open windows during lamination

Correct answer: Use PPE and follow lab protocols

Using Personal Protective Equipment (PPE) such as gloves, safety glasses, and respirators is crucial for protecting technicians from hazardous materials like resins, dust, and fumes common in a prosthetics lab. Adhering to established lab protocols ensures safe handling of tools, machinery, and chemicals, minimizing the risk of accidents and exposure to harmful substances.

Question 127: What is the most effective method for preventing cross-contamination?

Cleaning equipment once daily
Using antibiotics prophylactically
Proper hand hygiene and use of personal protective equipment (Correct answer)
Limiting patient interactions

Correct answer: Proper hand hygiene and use of personal protective equipment

Hand hygiene combined with appropriate PPE use is the cornerstone of infection prevention, creating multiple barriers against pathogen transmission.

ABC Certified Prosthetic Technician (CTP)

The ABC Certified Prosthetic Technician (CTP) exam evaluates knowledge of prosthetic fabrication techniques, anatomy, biomechanics, materials, componentry, and professional practice standards required to assist certified prosthetists in clinical and technical settings.

125

Questions

150 min

Time Limit

70%

To Pass

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