Question
A 64-year-old man with osteoarthritis of the knee comes to the physician for evaluation of weakness in his foot. Physical examination shows a swelling in the popliteal fossa. There is marked weakness when attempting to invert his right foot. He is unable to curl his toes. Further evaluation of this patient is most likely to show decreased sensation over which of the following locations?
| A. |
First dorsal web space
|
| B. |
Second dorsal web space
|
| C. |
Sole of the foot
|
| D. |
Medial plantar arch
|
Show Answer
|
Correct Answer � C
Explanation
|
|
Answer C) Sole of the foot
Explanation: Swelling of the popliteal fossa can lead to compression of the inlying structures, including the tibial nerve. Compression of the tibial nerve can result in neuropraxia, causing marked motor weakness of foot inversion and toe plantarflexion, as well as sensory deficits in the tibial nerve distribution.
Sole of the foot
-
The sole of the foot, lateral foot, and posterolateral leg are innervated by sensory branches of the tibial nerve (nerve stem from L4–S3).
-
The posterior compartment of the leg, responsible for foot inversion and plantarflexion of the toes and ankle, is innervated by motor branches of the tibial nerve.
-
This patient’s neuropraxia of the tibial nerve secondary to popliteal swelling would diminish the sensory and motor functions of these regions
Like this:
Like Loading...
