fig2

Figure 2. When decompression is insufficient, the nerve kinks at Osborne's arcade and is compressed by the intermuscular septum when transposed anteriorly. (a) The patient underwent two surgeries for simple nerve decompression. The nerve is dislocated anterior to the epitrochlear bone, presenting with a pseudoneuroma bulging (*) proximal to the compression area at Osborne's arcade level (>) which had not been previously released (<)(b) following decompression at zones 4 and 5 (refer to Figure 1) (<) and external neurolysis (*), nerve transposition may be performed; (c) anterior submuscular transposition using a muscle Z-lengthening procedure