Outcome of Surgical Repair and Rehabilitation of Flexor Tendon Injuries in Zone II of the Hand: Systematic Review and Meta-Analysis

A randomized controlled trial comparing controlled active motion and early passive mobilization protocols for rehabilitation of repaired flexor tendons in zone II

BACKGROUND

Flexor tendon injuries in zone II of the hand pose serious clinical complications due to the high risk of adhesion formation and suboptimal clinical outcomes, although controlled active motion (CAM) and early passive mobilization (EPM) are standard protocols used during rehabilitation.

OBJECTIVE

This randomized trial compared functional outcomes between CAM and EPM systems after zone II flexor tendon repair.

METHODS

Forty patients with entire zone II flexor digitorum profundus and superficialis tears were randomly assigned to either the CAM or EPM protocol for 12 weeks' rehabilitation. Total active motion (TAM), grip strength, and disability of the arm, shoulder, and hand (DASH) scores were assessed in the 6th and 12th week after the repair. Two-way mixed ANOVA was used to determine the effect of the treatment regarding the type of protocol and time within and between groups, as well as, Cohen's d was used to calculate the effect size.

RESULTS

There was a significant improvement over time in both groups for all measured outcomes (p < 0.001). However, CAM showed superior results than EPM across all time points (6th and 12th week); for TAM (p < 0.05, Cohen's d =11.8 and 9.9), grip strength (p < 0.05, Cohen's d = 7.97 and 9.7), and DASH score (p < 0.05, Cohen's d = 5.8 and 5.5). By 12 weeks, 80% of CAM patients achieved an "excellent" rating according to the Strickland formula of the TAM grading compared with 55% for the EPM group.

CONCLUSION

While both CAM and EPM protocols improve functional status after zone II flexor tendon repair, CAM confers a distinct early advantage in a digital range of motion and manual function compared with EPM. These data support the preferred adoption of the CAM rehabilitation approach after area II flexor tendon surgical repair.

Optimizing Flexor Digitorum Profundus Tendon Repair: A Narrative Review

Zone II flexor digitorum profundus (FDP) tendon injuries are complex, and present significant challenges in hand surgery, due to the need to balance strength and flexibility during repair. Traditional suture techniques often lead to complications such as adhesions or tendon rupture, prompting the exploration of novel strategies to improve outcomes. This review investigates the use of flexor digitorum superficialis (FDS) tendon autografts to reinforce FDP repairs, alongside the integration of biomaterials to enhance mechanical strength without sacrificing FDS tissue. Key biomaterials, including collagen-polycaprolactone (PCL) composites, are evaluated for their biocompatibility, mechanical integrity, and controlled degradation properties. Collagen-PCL emerges as a leading candidate, offering the potential to reduce adhesions and promote tendon healing. Although nanomaterials such as nanofibers and nanoparticles show promise in preventing adhesions and supporting cellular proliferation, their application remains limited by manufacturing challenges. By combining advanced repair techniques with biomaterials like collagen-PCL, this approach aims to improve surgical outcomes and minimize complications. Future research will focus on validating these findings in biological models, assessing tendon healing through imaging, and comparing the cost-effectiveness of biomaterial-enhanced repairs with traditional methods. This review underscores the potential for biomaterial-based approaches to transform FDP tendon repair.

Maximizing hand function following zone II flexor tendon repair: A systematic review and meta-analysis of rehabilitation strategies

Introduction

Injuries to the flexor tendons of the hand pose significant challenges in both surgical repair and postoperative rehabilitation. Despite advancements in techniques, there remains uncertainty about the most effective postoperative rehabilitation protocol/strategy. This study aims to address this debatable issue by evaluating different rehabilitation protocols following surgical repair in zone II flexor tendon repair.

Methods

A systematic review and meta-analysis followed PRISMA guidelines, searching databases up to December 2023. Inclusion criteria covered studies on zone II flexor tendon repair in adults, with various rehabilitation strategies and hand function as primary outcomes. Data extraction and bias assessment employed predefined tools.

Results

Among 916 initial articles, 28 met the inclusion criteria. Published from 1980 to 2023, these studies involved 1414 patients, predominantly affecting the little, index, and middle fingers. Various suture techniques and materials were used, with early active and passive motion as primary rehabilitation protocols.

Conclusion

This review highlights early active and passive motion as common postoperative rehabilitation strategies for zone II flexor tendon repair. While active motion showed greater range of motion improvement, both protocols had comparable reoperation rates and grip strength outcomes. Future research should focus on refining protocols and assessing long-term outcomes to optimize patient care.

Principles for Achieving Predictable Outcomes in Flexor Tendon Repair

Flexor tendon injuries require surgical repair. Early repair is optimal, but staged repair may be indicated for delayed presentations. Zone II flexor tendon injuries are the most difficult to achieve acceptable outcomes and require special attention for appropriate repair. Surgical techniques to repair flexor tendons have evolved over the past several decades and principles include core strand repair using at least a 4 strand technique, epitendinous suture to add strength and gliding properties, and pulley venting. Early postoperative active range of motion within the first 3 to 5 days of surgery is essential for optimizing outcomes.

Flexor Tendon Injuries

Flexor tendon injuries are complex, and management of these injuries requires consideration of the surgical timing, injury location, approach, and soft tissue handling. Complications are common, including adhesions, tendon rupture, infection, and a high reoperation rate for zone 2 repairs. Special considerations are given to chronic ruptures, concomitant fractures, and pediatric cases. We discuss current concepts that may improve patient outcomes.

Flexor tendon laceration of the hand from opening a glass ampoule

Sharps and needlestick injuries are serious work-related injuries to the hand in healthcare workers (HCWs). We present two cases of HCWs with hand injuries from opening a medicinal glass ampoule. The index finger (IF) was involved in both cases, with an associated flexor tendon injury, presenting as inability to flex the proximal and distal interphalangeal joints. Sensation was intact, and radiographs showed no foreign body.The surgical repair of the flexor tendon injury was carried out using the Wide-awake Local Anaesthesia No Tourniquet technique. The quality of the repair was tested intraoperatively. Physiotherapy involved gradual progression of finger flexion from 30% to 50% to full range of motion. At 36 and 42 months follow-up, they regained the IF range of motion and returned to work.Flexor tendon injuries from opening medicinal glass ampoules are rare but can be devastating, with a long rehabilitation process after surgical repair.