DPM Orthotic Device Prescription 3 — Questions and Answers
Question 1: A pediatric patient has a medially deviated subtalar joint axis confirmed on gait analysis. Which orthotic device best addresses excessive pronation in this presentation?
- Standard UCBL with neutral posting
- Gait plate
- Kirby medial heel skive technique (Correct answer)
- Lateral wedge with valgus post
Correct answer: Kirby medial heel skive technique
The Kirby medial heel skive shifts the subtalar joint axis laterally, increasing supination moments and reducing excessive pronation driven by a medially deviated axis.
Question 2: Which measurement is essential before prescribing a rigid functional foot orthosis for a patient with rearfoot varus?
- Ankle-brachial index
- Subtalar joint neutral position and total range of motion (Correct answer)
- Tibial torsion angle by CT
- Plantar fascia thickness via ultrasound
Correct answer: Subtalar joint neutral position and total range of motion
Subtalar joint neutral position and range of motion determine the degree of posting needed and whether the joint can be placed in the corrected position.
Question 3: A patient has bilateral plantar fasciitis unresponsive to stretching and NSAIDs. Which orthotic feature is most evidence-supported for this condition?
- Full-length carbon fiber plate
- Heel cushion with medial arch support (Correct answer)
- Rigid rearfoot post only
- Toe crest pad
Correct answer: Heel cushion with medial arch support
Prefabricated or custom orthotics with heel cushioning and medial longitudinal arch support have the strongest evidence for plantar fasciitis management.
Question 4: Which orthosis type is most appropriate for a patient with posterior tibial tendon dysfunction (PTTD) Stage II?
- Prefabricated arch support
- Arizona AFO or custom UCBL with deep heel cup (Correct answer)
- Carbon fiber toe plate
- Standard functional foot orthosis with 4° varus post
Correct answer: Arizona AFO or custom UCBL with deep heel cup
Stage II PTTD (flexible flatfoot with tendon dysfunction) requires rigid medial support such as an Arizona AFO or UCBL to control excessive pronation and offload the tendon.
Question 5: When casting for a functional foot orthosis using the suspension casting technique, the subtalar joint should be held in what position?
- Maximally pronated
- Maximally supinated
- Neutral position (Correct answer)
- 5° of pronation for functional alignment
Correct answer: Neutral position
The subtalar joint is held in neutral position during suspension casting to capture the ideal biomechanical alignment of the foot.
Question 6: A patient with rheumatoid arthritis has painful MTP joint subluxation. Which orthotic accommodation best reduces forefoot pain?
- Rigid Morton's extension
- Metatarsal pad placed just proximal to the metatarsal heads (Correct answer)
- Full-length steel shank
- Rearfoot valgus post
Correct answer: Metatarsal pad placed just proximal to the metatarsal heads
A metatarsal pad proximal to the metatarsal heads redistributes load away from the subluxed joints, reducing pain during ambulation.
Question 7: Which posting method in orthotic fabrication provides intrinsic correction by altering the cast itself rather than adding external material?
- Extrinsic post
- Intrinsic post (Correct answer)
- Wedge post
- Balance post
Correct answer: Intrinsic post
An intrinsic post is ground directly into the plaster cast positive model, becoming part of the orthotic shell rather than added underneath it.
DPM Orthotic Device Prescription 3
A pediatric patient has a medially deviated subtalar joint axis confirmed on gait analysis.
Which orthotic device best addresses excessive pronation in this presentation?