Abstract
Intro
Sciatic nerve injury (SNI) is a rare and potentially devastating complication after total hip arthroplasty (THA). Neural monitoring has been found in several studies to be useful in preventing SNI, but can be difficult to practically implement during surgery. In this study, we examine the results of using a handheld nerve stimulator for intraoperative sciatic nerve monitoring during complex THA requiring limb lengthening and/or significant manipulation of the sciatic nerve.
Methods
We retrospectively reviewed a consecutive series of 11 cases (9 patients, 11 hips) with either severe developmental dysplasia of the hip (Crowe 3–4) or other underlying conditions requiring complex hip reconstruction involving significant leg lengthening and/or nerve manipulation. Sciatic nerve function was monitored intra-operatively with a handheld nerve stimulator by obtaining pre- and post-reduction conduction thresholds during component trialling. The results of nerve stimulation were then used to influence intraoperative decision- making (downsizing components, shortening osteotomy).
Results
No permanent postoperative sciatic nerve complication occurred, with an average increase of 28.5mm in limb length, ranging from 6 to 51mm. In 2 out of 11 cases, a change in nerve response was identified after trial reduction, which resulted in an alternate surgical plan (femoral shortening osteotomy and downsizing femoral head). In the remainder cases, the stimulator demonstrated a response consistent with the baseline assessment, assuring that the appropriate lengthening was achieved without SNI. One patient had a transient motor and sensory peroneal nerve palsy, which resolved within two weeks.
Conclusions
The intraoperative use of a handheld nerve stimulator facilitates surgical decision-making and can potentially prevent SNI. The real-time assessment of nerve function allows immediate corrective action to be taken before nerve injury occurs.