A demyelinating condition that slows nerve conduction velocity Characteristics: 1. autosomal dominant 2. onset in first or second decade of life 3. most commonly leads to cavus foot 4. normal life expectancy 5. motor involvement more profound than sensory
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A 12-year-old girl who has a history of frequent tripping and falling also has bilateral symmetric hand weakness, high arched feet, absent patellar and Achilles tendon reflexes, and excessive wear on the lateral border of her shoes. She reports that she has multiple paternal family members with similar deformities. She most likely has a defect of what protein?
Peripheral myelin protein-22
Type I collagen
Cartilage oligomeric matrix protein
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Hereditary motor-sensory neuropathy (HSMN) primarily affects the peripheral nervous system. Which of the following are features of the most common type of HMSN
Death of both upper and lower motor neurons in the motor cortex of the brain, the brain stem, and the spinal cord leads to muscle twitching and atrophy
Impaired oxidation of branched chain fatty acids leads to neurologic damage, cerebellar degeneration, and peripheral neuropathy
Genetic mutations in axons or myelin protein leads to severe, rapidly progressive neurological damage by adolescence and complete loss of ambulation
Genetic mutations in axons or myelin protein leads to leg muscle atrophy, loss of sensation and proprioception in early adulthood
Movement disorder characterized by degeneration of midbrain neurons
An orthotic that provides laterally based hindfoot posting support would be most useful for which of the following conditions?
Painful accessory navicular
Middle facet coalition
Flexible flat foot
Flexible cavovarus foot
A mutation of PMP22 located at chromosome 17p12 most likely leads to an initial presentation highlighted by a:
Weak tibialis posterior
Weak peroneus longus
Strong peroneus brevis
Strong peroneus tertius
Weak tibialis anterior
A 42-year-old woman with Charcot-Marie-Tooth disease complains of longstanding foot pain. Orthotics, bracing, and NSAIDs no longer provide relief. She has cavovarus hindfoot deformity that does not correct with Coleman block testing. Radiographs are notable for degenerative changes within the talocalcaneal and calcaneocuboid joints. Which of the following is the most appropriate treatment?
Split tibialis posterior transfer
Lateral closing wedge calcaneal osteotomy with peroneus longus to brevis transfer
First metatarsal dorsal closing wedge osteotomy
Achilles tendon lengthening
A 24-year-old male with hereditary motor sensory neuropathy complains of worsening bilateral foot pain with ambulation and limited walking tolerance. Clinical photographs are shown in Figures A and B. The deformity corrects with Coleman block testing. Radiographs of the left foot are provided in Figures C-E. Which of the following is the best initial management for this patient?
Custom orthotics with posting of the lateral forefoot and lateral heel
Custom orthotics with posting of the medial forefoot and medial heel
Custom orthotics with medial heel posting and lateral forefoot recession
Gastrocnemius slide followed by dorsiflexion casting
Dorsal first metatarsal osteotomy with calcaneal slide osteotomy
A 22-year-old woman is concerned about frequent ankle sprains and an awkward gait. Lower extremity nerve conduction velocities show prolonged distal latencies in the peroneal nerves. DNA testing shows a duplication on chromosome 17. Which of the following images is most likely the radiograph of this patient?
A 14-year-old male child presents with the increasing foot deformity shown in Figure A. On physical exam, it is noted that he is unable to walk on his heels and has decreased Achilles reflexes bilaterally. Coleman block testing reveals correctable hindfoot deformity. Which procedure is associated with improved clinical outcomes in patients with the above described condition?
Transfer of peroneus brevis to peroneus longus
Split anterior tibial tendon transfer to lateral column
Posterior tibial tendon transfer through the interosseous membrane to dorsum of the foot
Lateral column lengthening calcaneal osteotomy
The cavus deformity in Charcot-Marie-Tooth disease is caused by what muscular imbalance?
Peroneus brevis overpowering peroneus longus
Tibialis anterior overpowering tibialis posterior
Achilles overpowering tibialis anterior
Extrinsic toe flexors overpowering intrinsics
Peroneus longus overpowering tibialis anterior
Plantar flexion of the first ray is the initial deformity seen in which condition?
Juvenile hallux valgus
A 17-year-old male complains of a foot deformity that has progressed over the past 1 year. He has pain along the lateral border of his foot with walking. His father has had similar problems with both feet throughout his life. A clinical photograph of the foot is provided in Figure A. Proper management of this patient should include evaluation for which of the following findings?
The PMP22 (peripheral myelin protein 22) is found at the cytogenetic location found in Figure A. What pediatric congenital disorder is associated with a mutation of this gene?
Duchenne's/Becker's muscular dystrophies
Spinal muscular atrophy
A 32 year-old male complains of lateral foot pain and a progressively awkward gait. He has a family history of "foot problems" and reports some minor burning and numbness in both feet. He has no other medical problems, and takes no medications. Physical exam reveals bilateral cavus feet with clawing of the toes and intrinsic muscle wasting of the hands. A clinical photograph is shown in Figure A. Which of the following is responsible for the patients initial symptoms and awkward gait?
Weak gastrocnemius-soleus complex
Peroneus brevis overpowering the posterior tibial tendon
Tibialis anterior overpowering the peroneus longus
Plantar flexion of the first ray
Clawing of the toes
Lateral forefoot and heel posts would be the appropriate orthotic for the foot deformities associated with which of the following conditions?
Stage II posterior tibial tendon insufficiency
Stage III posterior tibial tendon insufficiency
A 5-year-old boy has bilateral cavus feet and genetic testing reveals duplication of the PMP (peripheral myelin protein) gene on chromosome 17. What is the most likely diagnosis?