Flexor hallucis longus dysfunction.

Nineteen consecutive cases of flexor hallucis longus stenosing tenosynovitis that underwent operative tenolysis from September 1994 to December 1996 were retrospectively reviewed. This is classically a disorder of ballet dancers, and to a much lesser extent, running athletes. The patients were primarily nonathletic, male, and middle-aged. The mean symptom duration was 20 months, multiple physicians had been encountered, and misdiagnosis was common. Patients presented with overlapping signs and symptoms of flexor hallucis longus tendinitis, plantar fasciitis, and tarsal tunnel syndrome. A cross-reference of patients with posteromedial ankle pain, medial arch pain, and/or a positive Tinel's sign revealed that 14 (74%) and 6 (32%) feet had two of three, or all three signs, respectively. Magnetic resonance imaging and tenography proved valuable in establishing the correct primary diagnosis. Nonoperative protocols were unsuccessful. Flexor hallucis longus tenolysis was successful in each case with a mean return to regular activity at 9 weeks. Flexor hallucis longus stenosing tenosynovitis may be more prevalent than reported and should be a diagnosis of inclusion among all patient populations who present with posterior ankle, medial arch, and/or tarsal tunnel symptoms.