Mixed Deck — All OTC Topics Flashcards

Which of the following is the MOST significant factor contributing to thermal injury (burns) to the patient's skin during the application of a plaster cast?

Answer: Using water that is too hot to dip the plaster

The chemical reaction between plaster of Paris and water is exothermic, meaning it releases heat as it cures. Using water with a temperature greater than 24°C (75°F) dramatically increases the peak temperature of this reaction, significantly raising the risk of causing a thermal burn to the patient's underlying skin.

A wound left open to heal from the base upward through granulation tissue formation is healing by which method?

Answer: Secondary intention

Secondary intention healing allows a wound to fill with granulation tissue from the bottom up when primary closure is not possible, such as in infected or contaminated wounds.

When applying skin traction to a patient's lower leg, which of the following areas requires careful padding to prevent a common nerve injury?

Answer: The head of the fibula

The head of the fibula, located on the outer side of the leg just below the knee, is where the common peroneal nerve is most superficial. Applying pressure here with traction straps or bandages can lead to nerve compression, resulting in foot drop and sensory deficits. Therefore, this area must be well-padded and the straps applied carefully to avoid this complication.

A patient in a hip spica cast for a femur fracture develops severe, cramping abdominal pain, persistent nausea, and bilious vomiting several days after application. These symptoms are MOST indicative of which serious complication?

Answer: Cast Syndrome (SMA Syndrome)

Cast syndrome, or Superior Mesenteric Artery (SMA) syndrome, is a rare complication where a large body or spica cast compresses the third portion of the duodenum between the SMA and the aorta. This creates a functional bowel obstruction, leading to symptoms of severe nausea, vomiting, and abdominal pain.

An Orthopaedic Technologist is preparing materials for a lower extremity splint on an average-sized adult. Which of the following represents the recommended number of plaster layers for adequate strength?

Answer: 12 to 15 layers

For a lower extremity splint on an average-sized adult, 12 to 15 layers of plaster are typically required to provide sufficient strength and support. Upper extremities generally require fewer layers (6-10), while using too few on a lower extremity would compromise stability.

Which fracture pattern is most commonly associated with child abuse in pediatric patients?

Answer: Classic metaphyseal lesion (bucket-handle fracture)

Classic metaphyseal lesions, also called corner or bucket-handle fractures, are highly specific for non-accidental trauma in infants and young children.

Which traction type applies force directly through surgically implanted pins or wires into bone?

Answer: Skeletal traction

Skeletal traction uses pins or wires placed directly into bone to apply and maintain traction force, unlike skin traction which acts on soft tissue.

Which of the following describes the safest technique for an Orthopaedic Technologist to use when removing a cast with an oscillating cast saw?

Answer: Using a firm, in-and-out or "plunging" motion through the cast material.

A cast saw blade oscillates (vibrates back and forth) rather than spins. The correct and safest technique is to use a firm, plunging motion, pushing the blade through the cast material and then lifting it out before moving to the next adjacent spot. This method prevents the blade from dragging along the skin, which can cause friction burns or lacerations.

A patient with a thumb spica cast develops numbness and tingling in the thumb and index finger. This finding suggests compression of the:

Answer: Median nerve

The median nerve supplies sensation to the thumb, index, and middle fingers; compression under a thumb spica cast produces these symptoms.

Thermal injury during cast removal is most commonly caused by:

Answer: Heat generated by the oscillating saw blade

The oscillating saw blade generates friction heat, which can burn the skin if held too long in one spot, especially over bony prominences.

Which type of abnormal scar is characterized by excessive collagen growth that extends beyond the original wound boundary?

Answer: Keloid

A keloid grows beyond the original wound margins due to excessive collagen deposition and does not regress spontaneously, unlike hypertrophic scars which stay within wound boundaries.

When educating a patient about cast care, which instruction regarding moisture is correct?

Answer: Plaster casts must be kept dry; fiberglass casts may be waterproof if lined with Gore-Tex

Plaster casts are weakened by moisture, while fiberglass casts with a waterproof liner (e.g., Gore-Tex padding) can safely get wet.

Before removing a surgical drain from a post-operative orthopaedic wound, what is the most important prerequisite action?

Answer: Confirm a physician order for drain removal

Drain removal must always be performed under a physician's order, as premature removal can lead to hematoma, seroma, or fluid accumulation.

Which of the following is a primary advantage of using a splint over a circumferential cast for an acute lower extremity fracture?

Answer: It accommodates for soft tissue swelling.

The main advantage of a splint in the acute setting is that it is non-circumferential, which allows for swelling that naturally occurs after an injury. This significantly reduces the risk of pressure-related complications like skin breakdown and compartment syndrome compared to a rigid, circumferential cast.

A fracture occurring through bone that has been weakened by a pre-existing condition such as cancer or osteoporosis is classified as which type?

Answer: Pathologic fracture

A pathologic fracture occurs through diseased or structurally weakened bone and can result from minimal or no trauma.

What is the most appropriate first action when a surgical wound shows early signs of infection, including erythema, warmth, and purulent drainage?

Answer: Notify the treating physician immediately

Signs of wound infection must be promptly reported to the supervising physician so that appropriate intervention — antibiotics, wound opening, or cultures — can be ordered.

To ensure adequate protection and prevent skin irritation, how should cast padding be applied?

Answer: With a 50% overlap and extra layers over bony prominences

Cast padding should be applied with approximately 50% overlap to create at least two layers between the skin and the cast material. Bony prominences require extra padding to prevent pressure sores. Applying padding too tightly can be constrictive, while too little overlap can leave skin unprotected.

To minimize the risk of cutting or burning the patient's skin, what is the proper technique for using an oscillating cast saw?

Answer: Using a series of short, repeated "in-and-out" pressing motions.

An oscillating saw blade vibrates rapidly back and forth; it does not spin. The correct technique is to press the blade perpendicularly into the cast until it cuts through, then lift it and repeat this motion along the cut line. This "in-and-out" or "press-and-lift" method prevents heat buildup from friction and avoids dragging the blade across the skin, which could cause an abrasion or burn.

A patient with a mid-shaft ulnar and radial fracture (both-bone forearm fracture) requires immobilization. Which casting technique is MOST appropriate to effectively control forearm rotation?

Answer: Long arm cast

A long arm cast, which immobilizes the elbow in 90 degrees of flexion, is necessary to control pronation and supination of the forearm, thereby preventing displacement of both-bone forearm fractures. Short arm casts do not adequately control forearm rotation.

Which of the following is a primary advantage of using a sugar-tong splint over a circumferential cast for an acute, unstable distal forearm fracture?

Answer: It accommodates for initial swelling better than a circumferential cast.

A key advantage of splints, like the sugar-tong, is that they are not circumferential. This allows them to better accommodate the significant soft tissue swelling that often occurs with acute fractures, reducing the risk of compartment syndrome.