Monitoring of the sciatic nerve during hamstring lengthening by evoked EMG

K. Katz*, J. Attias, D. Weigl, A. Cizger, E. Bar-on

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

13 Scopus citations


Traction injury to the sciatic nerve can occur during hamstring lengthening. The aim of this study was to monitor the influence of hamstring lengthening on conduction in the sciatic nerve using evoked electromyography (EMG). Ten children with spastic cerebral palsy underwent bilateral distal hamstring lengthening. Before lengthening, the evoked potential was recorded with the patient prone. During lengthening, it was recorded with the knee flexed to 90°, 60° and 30°, and at the end of lengthening with the hip and knee extended. In all patients, the amplitude of the evoked EMG gradually decreased with increasing lengthening. The mean decrease with the knee flexed to 60° was 34° (10 to 77), and to 30°, 86% (52 to 98) compared with the pre-lengthening amplitude. On hip extension at the end of the lengthening procedure, the EMG returned to the pre-lengthening level. Monitoring of the evoked EMG potential of the sciatic nerve during and after hamstring lengthening, may be helpful in preventing traction injury.

Original languageEnglish
Pages (from-to)1059-1061
Number of pages3
JournalJournal of Bone and Joint Surgery - Series B
Issue number7
StatePublished - Sep 2004


Dive into the research topics of 'Monitoring of the sciatic nerve during hamstring lengthening by evoked EMG'. Together they form a unique fingerprint.

Cite this