Background: Achieving best outcomes for flexor tendon injuries in zone II of the hand remains a challenge to hand therapists and surgeons. With advances in the understanding of flexor tendon biomechanics and the development of multistrand core suture repair techniques, there has been a trend toward early active mobilization protocols post flexor tendon repair in zone II of the hand. Early active mobilization has been shown to minimize adhesion formation and increase repair strength. Many publications have also reported good outcomes when repaired flexor tendons in zone II were actively mobilized at an earlier stage. Objective: This systematic review seeks to identify an optimal early active mobilization protocol that brings about the best outcomes post flexor tendon zone II repair. Materials and Methods: PubMed, ScienceDirect, and Cochrane Library databases were searched to locate articles published from 1980 to February 2016. English studies that were included involved adult participants who (1) sustained flexor tendon injury to zone II of the hand, (2) had surgical repair done, and (3) underwent early active mobilization rehabilitation which was defined as any form of active digital flexion exercises within the first 4 weeks post repair, including place and hold. Studies that involved the thumb or lack details on the repair technique, rehabilitation protocol, and clinical outcomes were excluded. The primary outcomes were rupture rates and range of motion. In addition, surgical techniques, splint designs, therapy exercises, and regimes were also examined to identify the optimal early active mobilization rehabilitation protocol. Results: One hundred twelve articles were identified. Twelve studies met the inclusion criteria, with evidence ranging from level I to level IV. The rupture rates compared with number of core strand sutures were lowest with 6-strand repair (1.0%) compared with 4 (2.5%) and 2 (9.6%) strand repair. With a postoperative orthosis placing the wrist in neutral position, the rupture rate was low (2.7%) and had the highest excellent to good range of motion (90.6%) according to the original Strickland criteria. During the first 4 weeks of postoperative rehabilitation, a combination of high therapy frequency (daily to once a week) and low daily repetitions of active finger flexion exercises (not more than 2 repetitions per hour) involving active fisting, place and hold and synergistic wrist motion were shown to contribute to low rupture rates (<5%) and excellent range of motion (>85%) according to the original Strickland criteria. Conclusions: The optimal early active mobilization protocol is one that is used on flexor repairs with 4-strand core sutures and above, and a postrepair orthosis that puts the wrist in neutral position. With the integration of intensive therapist supervision and hourly low frequency active mobilization exercise program, this protocol can potentially improve the outcomes of flexor tendon repair in zone II.
