Flexor tendons flex (‘bend’) the fingers. Each finger has two (superficialis and deep or profundus) but thumb has only one. Ruptures are usually the result of trauma. There may be an injury of the digital neurovascular structures as well. Spontaneous ruptures can occur in long standing inflammatory diseases (ie rheumatoid arthritis).
Complete ruptures are treated surgically while partial ones may be treated conservatively. Surgical repair requires microsurgical expertise and is carried out with fine instruments and sutures under general, regional or local anaesthesia. If both tendons are torn, repair can be done to one or both. Every operative technique is followed by a detailed program of supervised mobilization that lasts about 12 weeks. Co-operative patients have the best results.
The most common postoperative complications are re-rupture of the tendon – mandating re-repair of the tendon – and development of symphysis (adhesions). In the latter surgical release is usually necessary because that greatly affects the range of motion of the finger(s). In both cases the expected outcome is poor.