COF Fitting & Adjustment Techniques 3 — Questions and Answers
Question 1: When fitting a thoracolumbosacral orthosis (TLSO), the superior trim line anteriorly should be positioned:
- At the sternal notch
- Two finger-widths below the sternal notch (Correct answer)
- At the xiphoid process
- One inch above the nipple line
Correct answer: Two finger-widths below the sternal notch
Positioning the anterior superior trim line two finger-widths below the sternal notch allows comfortable breathing and prevents impingement during sitting.
Question 2: A patient with a cervical orthosis reports persistent occipital pressure sores. The best corrective action is to:
- Reduce the height of the posterior occipital pad (Correct answer)
- Reposition the mandibular support anteriorly
- Increase padding on the posterior occipital panel
- Reduce the chin cup depth
Correct answer: Reduce the height of the posterior occipital pad
Reducing occipital pad height relieves direct contact pressure while maintaining cervical support.
Question 3: In fitting a scoliosis orthosis (TLSO), the apex pad is placed:
- Directly over the apex of the primary curve
- On the convex side of the curve at the apex level (Correct answer)
- On the concave side of the curve at the apex level
- At the transitional zone between primary and compensatory curves
Correct answer: On the convex side of the curve at the apex level
The apex pad applies a corrective force from the convex side to push the spine toward correction.
Question 4: When evaluating AFO fit during gait, heel rise during terminal stance indicates:
- The ankle is locked in excessive dorsiflexion
- The plantar flexion stop is too soft or absent (Correct answer)
- The footplate is too long
- The proximal trim line is impinging on the popliteal fossa
Correct answer: The plantar flexion stop is too soft or absent
Premature or excessive heel rise occurs when the plantar flexion stop does not adequately resist push-off forces.
Question 5: A key step when checking the fit of a custom foot orthosis (CFO) is to:
- Assess the patient standing with the orthosis on a flat surface before in-shoe check (Correct answer)
- Place the orthosis inside the shoe before any foot contact
- Measure the orthosis length against a ruler
- Verify the shell thickness with a caliper
Correct answer: Assess the patient standing with the orthosis on a flat surface before in-shoe check
Checking fit on a flat surface first allows visual inspection of contact, alignment, and edge clearance before the orthosis is enclosed in the shoe.
Question 6: The purpose of a metatarsal pad in an orthotic device is to:
- Support the longitudinal arch of the foot
- Unload the metatarsal heads by elevating the metatarsal shafts (Correct answer)
- Correct forefoot valgus
- Prevent hallux valgus progression
Correct answer: Unload the metatarsal heads by elevating the metatarsal shafts
A metatarsal pad placed proximal to the metatarsal heads transfers load to the shafts, reducing plantar pressure at the heads.
Question 7: When a patient with a trans-tibial prosthetic liner develops a proximal pistoning problem, the orthotic fitter assisting with liner management should first assess:
- Liner thickness and durometer
- Suspension mechanism integrity and pin lock engagement
- Socket brim height
- Residual limb volume with a circumferential tape measure (Correct answer)
Correct answer: Residual limb volume with a circumferential tape measure
Volume change in the residual limb is the most common cause of pistoning, making circumferential measurement the first clinical step.
COF Fitting & Adjustment Techniques 3
When fitting a thoracolumbosacral orthosis (TLSO), the superior trim line anteriorly should be positioned: