gms | German Medical Science

Objectives/Interrogation: We retrospectively reported the outcomes of flexor tendon repairs in zones 1 and 2 using a multi-strand core suture repair followed by early active mobilization, and evaluated the influencing factors on the recovery of flexor tendon repairs, including finger, age, gender, zone, time of surgery and associated nerve injury.

Methods: From January 2014 to August 2017, we performed primary or delayed primary repair for completely divisions of flexor digitorum profundus (FDP) tendon in zones 1 and 2 in 99 fingers (67 patients) using multi-strand core suture repair followed by early active mobilization. The FDP tendons were repaired in 11 fingers in zone 1, 16 in zone 2A, 24 in zone 2B, 35 in zone 2C and 13 in zone 2D. These included 27 index, 26 long, 29 ring, and 17 little fingers in 51 men and 16 women. Their mean age was 36 years (16 - 67 years). Fifty-eight fingers had associated digital nerve or artery injuries. All repairs were performed within 7 days after injury except six patients. We repaired the FDP tendons using either a 6-strand M-Tang or a 4-strand U-shaped Tang core suture with 4-0 looped sutures, followed by a running peripheral suture using a 6-0 nylon suture. We did not repair the superficialis tendon in any patients and vented the entire A4 pulley or a part of the A2 pulley when necessary. A digital extension-flexion test was always performed after tendon repair. Active partial range flexion exercise were initiated from day 3 to 5 after surgery. The outcomes were evaluated with Tang criteria. Kruskal-Wallis test and the Mann-Whitney U-test were used to compare outcomes between zone 1 and each zone 2 subzones.

Results and Conclusions: A total of 99 fingers were followed up from 6 months to 20 months (mean 8.7 months). According to Tang criteria, excellent or good function was achieved in 46 (47%) and 41 (42%) fingers, fair 9 (9%) and poor 2 (2%) at the final follow-up, respectively. The outcomes in zone 2D were significantly superior to those in zones 2C (p=0.002) and 1 (p=0.004). The functional outcomes of women were significantly better than those men (p=0.02). However, the effects of some other demographics and injury factors (different fingers, time of surgery and accompanied injuries) on the recovery of flexor tendon repairs were little. There was no significant difference in outcomes between zone 1 and zone 2 in general.

We conclude that flexor tendon repair in zone 2D has significantly better outcomes than in zone 1 or zone 2C.