The results of carpal tunnel release are generally good, but not all patients obtain complete and long lasting relief. Persistence of signs and symptoms after adequate decompression of the median nerve is uncommon. Forty-seven suboptimal results in thirty-four patients have been evaluated to determine the reasons for failure. Thirty-eight of the suboptimal results (81%) were associated with the persistent neck pain and/or abnormal cervical radiographs (typically narrowing of C5–6 and/or C6–7 disc spaces). This retrospective review supports a “double crush” phenomenon that influences both the manifestations of carpal tunnel syndrome and the outcome of its treatment.