[Recent isolated lesions of the flexor tendon of the thumb (20 cases). A long-term review]

Abstract

Purpose of the study: This study was performed to assess the long term functional result of Flexor Pollicis Longus tendon repair, with a special interest to the influence of associated neurovascular damages, surgical procedures and rehabilitation techniques.

Material: 20 out 30 patients operated between 1979 and 1994 returned for follow-up (average 5.3 years). The 10 patients lost for follow-up presented no significant epidemiological difference. The location of the laceration was classified according to the international Federation of Hand Surgery Societies (10 T1, 6 T2, 1 T3, 2 T4, 1 T5), and a 3 staged classification of neurovascular bundles damage was used.

Methods: A quantitative evaluation of the active range of motion (extension and flexion) of the interphalangeal joint (IP) was used and allowed calculation of the Tubiana's rating score. The pollici-digital key-pinch was assessed both qualitatively and quantitatively. All the data were compared with the opposite thumb.

Results: 85 per cent of patients had excellent or good results according to Tubiana's rating score. The mean flexion of the IP joint was 49.7 degrees (64 per cent of the opposite side), and the key-pinch strength was 69 per cent of its contralateral value. On the opposite, the mean extension was 0.75 degree and 3 patients complained about poor quality of their lateral key-pinch.

Discussion: A quantitative evaluation is more meaningful than a global rating score, especially for IP joint lack of extension, and could lead to underestimate the actual patient discomfort. Despite the absence of statistical relevance, lacerations of the 2 neurovascular bundles (stage III) seem to impair the final result. We have found no difference between different types of tendon sutures. A protected post-operative passive rehabilitation seemed to improve both motion and strength of the operated thumb.

Conclusion: There is no more discussion about the need to repair in emergency all the damaged structures of the thumb. We recommend wrist tendon lengthening when a pull-out suture is used, and when there is an impingement between suture and pulleys in T2 zone. We prefer a controlled-passive rehabilitation.