Peroneal Nerve Entrapment Research Articles

Peroneal nerve entrapment at the knee localized by short segment stimulation.

The purpose of this study was to evaluate the usefulness of short segment stimulation (SSS) of the peroneal nerve at the knee in order to localize the site of compression and/or entrapment of the nerve. Eighteen patients with suspected peroneal nerve palsy and 28 controls were studied by SSS of the peroneal nerve across the knee. Compound muscle action potentials (CMAPs) were obtained from the extensor digitorum brevis muscle after successive supramaximal stimuli of the nerve at 2 cm intervals, starting 4 cm distal (D4 and D2) and ending 6 cm proximal (P2, P4, and P6) to the fibular head prominence (P). In patients the average conduction times from D2 to P, P to P2, and P2 to P4 were significantly (P less than 0.05) longer and the average amplitude of CMAPs at P, P2, P4, and P6 significantly (P less than 0.05) lower than those of controls. Fourteen patients showed statistically significant reduction in amplitude and prolongation of conduction time in one or more short segments. Three patients had prolongation of conduction time only and one patient had reduction in amplitude only. When nerve conduction of the entire 10-cm segment across the knee was tested by the conventional method, only nine showed reduction in amplitude from proximal stimulation, or slowing of motor conduction velocity across the 10-cm segment or both. It was concluded that the SSS technique is a sensitive and reliable procedure for the detection of mild compression or entrapment of the peroneal nerve around the knee.

The Pseudoradicular Syndrome

Of approximately 4,000 patients with complaints of lower extremity pain who were referred to our center for evaluation of suspected lumbar radiculopathy, 36 were found to have peripheral nerve entrapments as the sole cause of their leg pain. Nine patients had femoral nerve entrapments just proximal to the inguinal ligament. Seven patients had saphenous nerve entrapments about the knee. Twenty patients had peroneal nerve entrapments at or above the popliteal space. Nine patients had tibial nerve entrapments in the popliteal space. The diagnosis was established on the basis of electrophysiologic studies coupled with the results of selective spinal and peripheral nerve blocks. Seven patients with saphenous nerve lesions, 12 patients with peroneal nerve lesions, nine patients with tibial nerve lesions, and four patients with femoral nerve lesions, for a total of 32 (71%) cases underwent surgical exploration and external neurolysis. Forty-four percent of the cases had a positive nerve root tension sign, and 44% (20/45) had spinal range of motion abnormalities. Back pain complaints were noted in 49% (22/45) of the cases. The pseudoradicular syndrome should be considered in cases of undiagnosed persistent leg pain. Peripheral nerve lesions should be ruled out prior to considering lumbar spine surgery.

MRI of peroneal nerve entrapment due to a ganglion cyst

Ganglion cysts are relatively common entities, but impingement upon the peripheral nerves is rare. We describe a case in which peroneal nerve palsy was caused by a ganglion cyst demonstrated by MRI.

Decompression for peroneal nerve entrapment.

I reviewed 24 patients after decompression for peroneal entrapment neuropathy; in 3 cases the lesion was bilateral. There were 15 males and 9 females; mean age 44 (12-72) years. The etiology was an operation around the knee in 12, a tibial fracture in 2, a slight compression in 1, an ankle sprain in 2, excessive climbing in 2, sitting in a cross-legged position in 4, and in 4 cases no reason was found. There was foot drop in 15 and ankle instability in 12 cases. The nerve was decompressed after an average period of 17 months (4 days-8 years). Immediate relief of symptoms was achieved in 14 cases, slower relief in 10, and in 3 cases there was no recovery. In peroneal neuropathy, decompression should be considered after 2 months without recovery and after 4 months when recovery is slow.

Common Peroneal Nerve Entrapment in a Hemophiliac

Traumatic neuropathies of the common peroneal nerve at the head of the fibula are relatively common, but nerve entrapment at this site is rarely encountered. A 55-year-old man with hemophilia A in whom common peroneal nerve entrapment occurred secondary to a probable muscle hematoma is described.

Percutaneous localization of conduction abnormalities in human entrapment neuropathies.

SUMMARY:In human entrapment neuropathies the characteristic abnormalities in conduction are frequently limited to a short segment of the nerve. Recognition and precise localization of these discrete conduction abnormalities may require measurement of conduction over shorter lengths of the nerves than those lengths commonly employed in the clinical laboratory. Techniques are described for the more precise location of the primary conduction abnormalities in median, ulnar and peroneal nerve entrapments. Distinctive or atypical locations of the major conduction abnormalities may point towards different mechanisms in the pathogenesis of these localized neuropathies.