Tenosynovitis of the posterior tibial tendon.

PTT tenosynovitis is a recognized entity no longer confused with an ankle sprain. Three possible causes are (1) overuse or age related (mechanical in cause, true stage I disease), (2) seronegative spondyloarthropathies (clinical suspicion, hematologic analysis), and (3) rheumatoid arthritis (deformity may be owing to ligamentous or capsular destruction). The PTT has a hypovascular zone 40 mm proximal to the insertion of the tendon and 14 mm in length. Pain often is localized to this portion of the tendon (primarily in stage I disease). Ultrasound is an inexpensive and accurate method to assist in the diagnosis of this condition and may replace MR imaging as more experienced ultrasonographers appear. The initial management of PTT tenosynovitis includes tendon rest and nonsteroidal anti-inflammatory medication and physical therapy. Surgical synovial débridement is performed early (6 weeks) in patients with enthesopathies (seronegative disease). This procedure may be delayed 3 months in patients with true stage I disease. At surgery, the undersurface of the tendon must be inspected for longitudinal split tears, and these must be repaired with nonabsorbable suture, burying the knots. The excursion of the tendon should be checked intraoperatively. Patients with stage I disease should be evaluated carefully for preoperative structural deformity to choose the appropriate surgical procedure and prevent failure of isolated tenosynovectomy.