Objective: To evaluate the role of modified H reflexes in confirming a diagnosis of piriformis muscle syndrome. Methods: Six consecutive patients who met stringent inclusion criteria establishing the presence of this disorder underwent electrodiagnostic testing including the completion of modified H reflexes as described by Fishman. Results: A positive predictive value of 33% was obtained. Conclusions: This study does not support the role of electrodiagnostic testing with modified H reflexes in the evaluation of a patient with possible piriformis muscle syndrome. An algorithmic approach for the diagnosis of piriformis syndrome which incorporates examination findings, injection techniques, and visual anatomic studies, is offered.
All Science Journal Classification (ASJC) codes