Neurolysis for secondary sciatic nerve entrapment: evaluation of surgical feasibility and functional outcome.

Abstract

The study included 11 patients; seven males and four females with mean age of 68.3 ±11 years. All patients had sciatic nerve entrapment: three had a penetrating injury, three suffered postoperative trauma, two had a crush injury, two had inadvertent injections and one was trapped in a machine belt. Clinical examination included: an evaluation of the extent of motor and sensory impacts according to the British Medical Research Council (BMRC) scale and the Semmes-Weinstein monofilament test; assessment of pain sensation using the visual analogue scale (VAS); electromyography; and nerve conduction velocitiey determination. The applied operative procedure for sciatic neurolysis was modulated according to the suspected site of sciatic nerve entrapment. At 6 and 12 months after surgery all patients were evaluated for recovery of motor and sensory function. All patients passed the smooth intraoperative course within a mean operative time of 77.7 ±21 min. The mean duration of wound drainage and postoperative hospital stay was 2.6 ±0.7 and 4.8 ±0.8 days, respectively. Pain sensation showed progressive significant improvement in nine patients but decreased at time of discharge and remained stationary till 12-m post-operative (PO). Recovery of motor function showed progressive significant improvement at 6 and 12 months after sciatic nerve neurolysis. The frequency of patients having muscle power recovery and regained sensation was significantly higher at 6-m and 12-m PO as compared to preoperative grading with a significantly higher frequency at the 6-m grading compared to preoperative grading. Two patients showed no change of their muscle strength grade, while nine patients showed improvement for a total success rate of motor strength recovery of 81.8%. At 6- m PO five patients showed no change of their sensory group, while six patients showed improvement for a total success rate of sensation recovery of 54.5%. At 12-m PO ten patients had fullly recovered protective sensation for a success rate of 90.9%. Surgical exploration and neurolysis of cases with sciatic nerve entrapment is a safe and effective therapeutic modality with significant improvement of both motor and sensory functions without risk of additional deficit secondary to neurolysis.