Bilateral piriformis syndrome after total hip arthroplasty.

We present the case of a 39-year-old man with bilateral piriformis syndrome 4 and 6 years after two cementless total hip arthroplasties, respectively. During surgical exploration, each sciatic nerve was found to be entrapped by a tense piriformis muscle and hypertrophic posterior hip capsule. The sciatic-type pain was relieved after sectioning each piriformis muscle with external neurolysis. This is the first reported case of piriformis syndrome after total hip arthroplasty.