Abstract
Nerve palsy occurring after elective primary total hip arthroplasty (THA) is a devastating complication because of its effect on motor strength, walking ability, potential for pain, and unexpected nature. In general, the nerve distribution involved is the peroneal branch of the sciatic nerve, and the level of involvement is usually mixed motor and sensory.
Prior publications have associated limb lengthening, dysplasia and use of the posterior approach to be associated with a higher incidence of nerve palsy. In the literature, the incidence of sciatic nerve palsy is estimated to be 0.2 to 1.9%.
We examined the rate of sciatic nerve palsy after THA performed by the joint replacement service at Hospital for Special Surgery between the years 1998–2013. Each case was matched with 2 controls that underwent THA and did not develop postoperative neuropathy. Controls were matched by surgical date having been within 7 days of their matched case's surgery date. Patient and surgical variables were reviewed using data from patient charts and the institution's total joint replacement registry. A multivariable logistic regression model was created to identify potential risk factors for neuropathy following THA while adjusting for potential confounders.
We found that, of 39,056 primary THA cases, there were 81 cases of sciatic nerve palsy, giving an incidence of 0.21%. The factors with the greatest odds ratios for nerve palsy were: history of smoking (OR=3.45); history of spinal stenosis (OR=4.45), and time of day of 1PM or later (OR=3.98). We did not find limb lengthening, dysplasia, or type of fixation to be associated with nerve palsy.
In conclusion, post-surgical neuropathy has a low incidence after primary THA, but at our institution, was associated with several factors. Spine-related comorbidities, such as spinal stenosis and lumbar spine disease, and smoking history should be closely monitored to inform the patient and surgeon for the potential increased risk of postoperative neuropathy following THA.
