Flexor Tendon Repair Research Articles

Two-Stage Flexor Tendon Reconstruction for Finger Contracture Secondary to Phlegmon: A Case Report

Flexor tendon reconstruction is a complex surgical procedure that requires great precision and specialized expertise. It remains a preferred treatment for patients with neglected lacerations of the digital flexor tendon and after the failure of flexor tendon repair. Improvements in tendon repair methods and follow-up techniques have enhanced outcomes after flexor tendon grafting. Case Presentation: A 14-year-old girl with a history of a phlegmon of the 4th finger of the right hand, treated with antibiotics and drainage. The evolution is marked after 2 years by the progressive development of a flexion contracture of the proximal interphalangeal (PIP) joint. On examination, there is a flexion attitude and an inability to extend the PIP joint without vascular or nervous disorders. A two-stage reconstruction was performed using the palmaris longus tendon as a graft. With a follow-up of 3 years, the girl has recovered complete flexion and has limited extension to 25° at the PIP joint. An arthrolysis was proposed, but the girl refused, and she is satisfied with the results.

Passive Mobilization With Place-and-Hold Versus Active Mobilization Therapy After Flexor Tendon Repair: 5-Year Minimum Follow-Up of a Randomized Controlled Trial

There is no consensus on the optimal postoperative rehabilitation program following flexor tendon repair. Some studies suggest a faster recovery after active mobilization, whereas other studies have failed to find any differences between active and passive mobilization at 12 months. To our knowledge, no prior randomized controlled trial has compared the long-term effects of these two approaches. This randomized controlled trial compared the long-term outcomes of active mobilization with those of passive mobilization in combination with place-and-hold. Sixty-four patients with a flexor tendon injury in zones I or II were included in the study. After surgery, patients were randomized to either active mobilization or passive mobilization with place-and-hold. Forty-seven patients were available for the 5-year minimum follow-up. Assessments included range of motion, grip strength, key pinch, as well as the Disabilities of the Arm, Shoulder, and Hand (DASH) and ABILHAND questionnaires. At the 5-year minimum follow-up, range of motion was significantly better in the group treated with passive mobilization with place-and-hold compared with the active mobilization group. Furthermore, there was a significant deterioration in the range of motion and an increased flexion contracture in the active mobilization group compared with 1 year after surgery. Grip strength deteriorated significantly in both groups from the 1-year to the 5-year minimum follow-up, but key pinch did not change. In both groups, DASH and ABILHAND scores improved from the 1-year to the 5-year minimum follow-up. Passive mobilization with place-and-hold following flexor tendon repair results in superior long-term outcomes compared with active mobilization. Therapeutic I.

Biomechanical Comparison of Three Modified Kessler Techniques for Flexor Tendon Repair: Implications in Surgical Practice and Early Active Mobilization.

Objective: Managing flexor tendon injuries surgically remains challenging due to the ongoing debate over the most effective suture technique and materials. An optimal repair must be technically feasible while providing enough strength to allow for early active mobilization during the post-operative phase. This study aimed to assess the biomechanical properties of three modified Kessler repair techniques using two different suture materials: a conventional two-strand and a modified four-strand Kirchmayr-Kessler repair using 3-0 Prolene® (2s-KK-P and 4s-KK-P respectively), and a four-strand Kessler-Tsuge repair using 4-0 FiberLoop® (4s-KT-FL). Methods: Human flexor digitorum profundus (FDP) tendons were retrieved from Thiel-embalmed prosections. For each tendon, a full-thickness cross-sectional incision was created, and the ends were reattached using either a 2s-KK-P (n = 30), a 4s-KK-P (n = 30), or a 4s-KT-FL repair (n = 30). The repaired tendons were tested using either a quasi-static (n = 45) or cyclic testing protocol (n = 45). Maximum force (Fmax), 2 mm gap force (F2mm), and primary failure modes were recorded. Results: In both quasi-static and cyclic testing groups, tendons repaired using the 4s-KT-FL approach exhibited higher Fmax and F2mm values compared to the 2s-KK-P or 4s-KK-P repairs. Fmax was significantly higher with a 4s-KK-P versus 2s-KK-P repair, but there was no significant difference in F2mm. Suture pull-out was the main failure mode for the 4s-KT-FL repair, while suture breakage was the primary failure mode in 2s- and 4s-KK-P repairs. Conclusions: FDP tendons repaired using the 4s-KT-FL approach demonstrated superior biomechanical performance compared to 2s- and 4s-KK-P repairs, suggesting that the 4s-KT-FL tendon repair could potentially reduce the risk of gapping or re-rupture during early active mobilization.

Effect of hydroalcoholic extract of Sambucus nigra on superficial digital flexor tendon repair in rabbit by ultrasonography and histopathology.

Adult tendon tissue has limited and slow regenerative capacity. Sambucus nigra plant possesses antioxidant and anti-inflammatory attributes. This study aimed to evaluate the effect of hydroalcoholic extract of this plant's fruit on superficial digital flexor tendon repair in rabbits (SDFT). Twenty-five male New Zealand white rabbits weighing 1.5-2kg were selected, quarantined and randomly divided into four groups of six. By performing a partial left posterior limb tenotomy, differentiating the SDFT and creating multiple scrapes were performed. During 3 consecutive days post-surgery, the positive control group was injected with 0.5mg/kg dexamethasone, whereas the treatment groups received extract doses of 200 and 400mg/kg, respectively. The negative control group did not receive any medication. Evaluation of sonographic and histopathological parameters was conducted on days 0, 7 and 28 post-surgeries. Findings were analysed and compared using SPSS22. Both treatment groups showed significant differences in echogenicity, and collagen fibre alignment compared to the control and positive control groups, in sonographic evaluation. Histopathological examination revealed fewer inflammatory cells and increased collagen fibre formation in the treatment groups compared to the other two groups. No significant difference in angiogenesis was observed among the groups on days 7 and 28 (p value <0.05). The results indicate that the S. nigra fruit extract, by stimulating collagen synthesis and reducing inflammation, effectively accelerates the healing process of injured tendons.

Innovating Flexor Tendon Repair Training with a Three-dimensional Printed Model.

Flexor tendon repair is a technically demanding procedure, with functional outcome directly proportional to skillful execution. A repair must be strong to manage early mobilization and precise to allow for gliding through the tendon sheath. As a result, junior residents face a steep learning curve that may be mitigated by exposure to surgical simulators. To facilitate flexor tendon repair training, a surgical training device and accompanying instructional video were developed. Simulation workshops were held for junior orthopedic and plastic surgery residents (n = 11). To objectively assess validity of the curriculum, study participants performed cadaveric flexor tendon repairs before and after the workshop. Anonymous recordings of these repairs were graded by two certified hand surgeons. Additionally, a tensometer was used to measure strength of repair. Model realism, educational utility, and overall usefulness rated high: 4.6 ± 0.52 95% confidence interval (CI) for realism, 4.9 ± 0.42 95% CI for device, 4.7 ± 0.96 95% CI for video, and 4.9 ± 0.66 95% CI overall. Subjective confidence increased after the training session (73% ranked "moderately" or "extremely"). Likewise, scores given by the surgeons grading the repairs improved for overall quality and time of repair (pre: 2.77 ± 0.61, post: 4.22 ± 0.56, P= 0.0002). Strength of repair did not change (P = 0.87). The proposed three-dimensional surgical simulator for flexor tendon repair is realistic and useful, with improved surgical technique and improved confidence demonstrated after use. This design can be three-dimensionally printed en masse and provide value to hand surgery training curriculum.

Range of Motion Following Flexor Tendon Repair: Comparing Active Flexion and Extension With Passive Flexion Using Rubber Bands Followed by Active Extension

This study aimed to compare the outcome in terms of range of motion between early active flexion and extension (early active motion, [EAM]) and passive flexion using rubber bands followed by active extension (sometimes referred to as a Kleinert regimen) after flexor tendon repair in zones 1 and2. Data were collected from the Swedish national health care registry for hand surgery (HAKIR). Rehabilitation regimens were decided by the preference of each caregiver. At 3 months, 828 digits (656 EAM and 172 passive flexion) and at 12 months, 448 digits (373 EAM and 75 passive flexion) were available for analysis. Thumbs were analyzed separately. No notable difference in total active motion was found between the groups at 12 months of follow-up. This large registry study supports the hypothesis that EAM rehabilitation may not lead to better range of motion long-term than passive motion protocols. Therapeutic IV.

Zone-specific pitfalls in flexor tendon rehabilitation: management and prevention.

Despite significant advancements in flexor tendon repair techniques and rehabilitation strategies, achieving complete restoration of digital motion remains a formidable challenge. The most prevalent complications associated with tendon repair are the development of tendon adhesions and joint contractures. Left unaddressed, these complications can further lead to secondary pathomechanical changes, resulting in fixed deformities significantly affecting hand function. This review of zone-specific considerations in flexor tendon rehabilitation provides an in-depth analysis of the dynamics of tendon motion after repair and strategies to minimize common secondary complications.

Injury and Section of Flexors in Zone II

Flexor tendon repair is a challenging task in hand surgery, with numerous studies and publications on the subject. The incidence of flexor tendon injuries in India is estimated to be around 14/100,000-person years. The fingers are characterized by five zones: Zone I, Zone II, Zone III, Zone IV, and Zone V. Reparation of these zones involves flap extension, suturing, and band repair. However, tendon repair is fraught with complications, with the most catastrophic outcome being rupture. Tendon adhesions are a common consequence of the healing process and can be limited with atraumatic surgical techniques, robust repair, and early mobilization strategies. Ultrasound imaging is helpful in determining the continuity of the flexor tendon. Tenolysis surgery may be necessary if treatment is unsuccessful, but is generally recommended after three to six months.

Outcomes of Zone II Flexor Tendon Repair Under General Versus Wide Awake Local Anesthesia: A Randomized Controlled Trial

Wide awake local anesthesia no tourniquet (WALANT) is gaining popularity with flexor tendon repair. We hypothesized that results of zone II flexor tendon repair performed under WALANT would be superior to those performed under general anesthesia (GA). A randomized controlled trial was conducted to compare results of repair of zone II flexor tendon lacerations under WALANT versus GA. Following sample size estimation, 86 digits were included and randomized into two groups. All surgeries were performed by a single surgeon using a six-stranded core stitch and running epitenon suture. All patients followed the same early active rehabilitation protocol. The primary outcome was recovery calculated using the Strickland and Glogovac criteria. Secondary outcomes included rupture rate, complication rate, and Disabilities of the Arm, Shoulder, and Hand (DASH) score. All outcomes were reported at the 6-month visit for all patients. Of the 86 digits, three were lost to follow-up. Analysis was performed on 43 digits in the WALANT group and 40 in the GA group. Demographic characteristics including age and sex were comparable in both groups. Rupture of the repair occurred in two digits in each of the WALANT and GA groups. An excellent or good outcome was achieved in 49% and 56% of the digits in the WALANT and GA groups, respectively. This difference was not statistically significant. DASH scores averaged 12.9 and 8.4 for the WALANT and GA groups, respectively. WALANT may not be superior to GA in regards function, rates of rupture, and patient-reported outcomes in repair of zone II flexor tendon lacerations. Surgeons can be confident in choosing either technique if rigorous patient selection, sound surgical technique, and proper hand therapy are employed. Therapeutic I.

Cost Comparison of Digital Nerve Repair Techniques.

Direct cost comparison of nerve allograft with other techniques for repairing short digital nerve gaps are lacking. This study compares the costs of various techniques for digital nerve repair, anticipating significant cost increases for allograft implants. The State Ambulatory Surgery and Services Database for Florida, New York, and Wisconsin from 2015-2020 was used. Patients with primary repair, short autograft, conduit, and allograft were compared along total, surgical supply, operating room (OR), and anesthesia charges. Among 5,009 patients were 2,967 primary nerve repairs (59.2%), 77 autografts (1.5%), 1,647 conduits (32.9%), and 318 allografts (6.3%). 2,886 patients were male (57.6%) with mean age 40.4 ± 16.3 years. Over the study period, primary repairs decreased (63.9% in 2015 to 56.3% in 2020) while allografts increased significantly (8.8% in 2018 to 12.6% in 2020).Median total charges significantly varied across procedures, with the most expensive being allograft ($35,295), followed by conduit ($25,717), autograft ($24,749), and primary repair ($18,767). On multivariable regression, allograft is significantly more expensive than autograft for total charges by $11,224 (95CI: $4,196-$18,252) and supply charges by $10,484 (95CI: $6,073-$14,896), but not for OR or anesthesia charges. Flexor tendon repair was associated with greater total, OR, and anesthesia charges but similar supply charges. Nerve allograft is the most expensive digital nerve repair technique most likely due to the cost of the implant. To minimize health care expenditure and ensure equitable patient access, surgeons should consider this cost along with clinical factors in choosing digital nerve repair techniques.

Outcomes of Amniotic Membrane Use as an Allograft in Flexor Tendon Repair

Outcomes of Amniotic Membrane Use as an Allograft in Flexor Tendon Repair

Comparison of Kleinert versus Saint John protocol in Zone I/II flexor tendon injuries: A retrospective study

Background: There is no concrete evidence to define the optimal mobilization strategy following zone I/II flexor tendon repair. The Saint John Protocol is an active motion regime which utilizes wrist movement to facilitate better clinical outcomes. Our objective was to compare the outcomes of patients who underwent the conventional Kleinert protocol versus the Saint John protocol. Methods: 20 fingers in the Kleinert group and 18 fingers in the Saint John group were included in this retrospective study. Pain score, range of movement, grip strength, and complications were studied at 6 and 12 weeks postoperatively. Results: The Saint John protocol showed significantly less pain at 6 week (0.167 vs 1.08, P = 0.032) and less flexion contracture at the PIPJ at 6 weeks (3.33 vs 12.25, P = 0.032). Both groups showed similar rerupture rates (5.5% vs 5%). Conclusions: Saint John protocol demonstrated better clinical outcomes while not sacrificing the integrity of repair.

A Nationwide Analysis of Complications, Reoperations and Cost of Wide-Awake Flexor Tendon Repairs.

Some papers suggest that wide-awake flexor tendon repair (FTR) may reduce rates of postoperative tendon gapping and rupture due to improved intraoperative testing of the repair. The current study is a nationwide cohort study comparing FTRs performed wide-awake and with traditional anesthesia. Patients undergoing zone II FTR between 2010-2022 were identified in PearlDiver. Exclusion criteria were other tendon repairs, concomitant treatment for vascular injury, fracture, dislocation or amputation, inpatient or office surgery, age <18 years and <1 year of follow-up. Patients were stratified by anesthesia technique: traditional anesthesia (general anesthesia, monitored anesthesia care, regional blocks) or wide-awake. Patients were matched based on age, sex, Elixhauser Comorbidity Index (ECI) score, geographical region, insurance coverage, number of tendon repairs and presence of concomitant nerve repair. 30-day wound complications, emergency department visits and readmissions and 1-year reoperations were identified. Total reimbursement for surgery was determined. Each matched cohort included 2,563 patients. Wide-awake patients had fewer 30-day emergency department visits (2.7% vs 4.8%). There were no differences in 30-day wound complications or readmissions. There was no difference in 1-year reoperations for rupture or for stiffness. Multivariable linear regression identified wide-awake surgery to be a significantly associated with lower total reimbursement. Performing digital FTR using wide-awake techniques can reduce costs, but the hypothesis that wide-awake repairs may reduce rates of tendon rupture was not supported by the current study.

Comparative Evaluation of Effectiveness of Lesser Toe Surgical Correction

INTRODUCTION: The relevance of improving algorithms of surgical correction of lesser toes (SCLT) is due to a high incidence of hammertoe deformity syndrome, its negative impact on the working capacity and quality of life, and to a considerable degree of dissatisfaction of patients with the results of surgical treatment. AIM: To evaluate the effectiveness of an improved SCLT algorithm using a modified fixed B. Helal osteotomy and combined plantar plate (PP) and toe flexor tendon repair. MATERIALS AND METHODS: The prospective study included 167 female patients with a severe deformity of the second lesser toe. In 83 patients of the control group, the stability of the metatarsophalangeal joint was restored through surgical PP repair. In the main group (n = 84), along with elimination of PP defect, the second toe flexor tendon repair was performed. The condition of the second lesser toe before and one year after its surgical correction was evaluated using clinical and X-ray methods and a questionnaire. RESULTS: At the stage of assessing the long-term results of treatment in the main group, the integral score of ACFAS Module 2 scale increased by 63 points relative to the preoperative value, which appeared to be 22 points more (Uemp = 3687, Ucr = 4894, р ˂ 0.01) than a similar change in the control group. One year after surgery, the incidence of the floating toe syndrome and its residual hyperextension in the main group decreased by 10.8% (φ*emp = 0.007, р ˂ 0.05) and 8.8% (φ*emp = 0.016, р ˂ 0.05), respectively. CONCLUSIONS: Application of the improved algorithm permitted to improve the SCLT effectiveness, which was confirmed by a statistically significant improvement of the long-term results of treatment of patients in the main group compared to the control group.

Wide-Awake Local Anesthesia No Tourniquet (WALANT) versus Regional Anesthesia with Tourniquet for Hand Flexor Tendon Repair Surgeries in Adults

Abstract Background Flexor tendon injuries represent a significant percentage of admissions in emergency departments in Egypt. A bloodless surgical field is important to perform a hand surgery. Traditionally, a tourniquet is used for hemostasis, and the standered anesthetic techniques utilized in hand surgery were general anesthesia, intravenous regional anesthesia, or brachial plexus block. Recently the evolving Wide-Awake Local Anesthesia No Tourniquet (WALANT) technique where patient is operated on under local anesthesia and hemostasis is achieved via adrenaline could be a better choice. Aim of this work is to compare the intraoperative pain scores, induction time, operating time, blood loss, postoperative pain scores, and patient satisfaction with WALANT versus supraclavicular brachial plexus block (SC-BPB ) with tourniquet, in patients undergoing flexor tendon repair. Patients and Methods In the current study 52 patients who underwent flexor tendon intervention were divided randomly into two groups, each group consisting of 26 patients. Group A: Patients in this group received WALANT. Group B: Patients in this group received SC-BPB with a tourniquet applied to the arm. Results Intraoperative Wong-Baker Faces scale revealed no statistically significant difference in intraoperative pain scores in both groups, except during injection (p = 0.04). Tourniquet-related pain was reported in 23% of patients of SC-BPB group (p = 0.001). Induction time was significantly shorter in WALANT (p &amp;lt; 0.01) but time needed to obtain sufficient hemostasis is significantly more in WALANT than SC-BPB (p &amp;lt; 0.01) while surgical time was similar in both groups (p = 0.538). Blood loss in spite of being minimal it was statistically significant higher in WALANT (p &amp;lt; 0.01). Conclusion WALANT anesthesia was found to be better alternative to SC-BPB in flexor tendon repair surgeries in adults being more simple technique and no need for special skills or ultrasound device, less time consumed in induction and less injection pain also no tourniquet-related pain, intraoperative active motion of the hand is preserved facilitating surgical technique, better effect on postoperative analgesia and more patient and surgeon satisfaction.

Which is more effective? Porcine tendon or 3D- printed flexor tendon? A study of model realism and educational utility in a flexor tendon repair workshop

IntroductionAnimal models in orthopaedic surgical training have raised concerns about ethics and availability, prompting the search for non-animal alternatives. The 3D-printed silicone tendon model has emerged as a potential alternative due to its hygiene and reusability. This study aimed to compare the effectiveness of the two models for flexor tendon repair training. Materials and methodsA survey involved 25 postgraduate trainees with no prior experience in flexor tendon repair. Porcine tendon models and 3D-printed models were used, with participants evaluating accuracy, understanding of pulley systems, joint flexion, tissue feel, and model realism. Repairs were evaluated by experienced surgeons, and participants completed a survey. ResultsBoth models demonstrated satisfactory accuracy and realistic joint flexion. The porcine model scored higher in anatomical accuracy, while the 3D-printed model excelled in understanding pulley systems. The porcine model provided realistic tissue feel, while the 3D-printed model facilitated anatomy teaching. No significant difference was found in educational utility. The 3D-model was perceived as hygienic and odourless, whereas the porcine model offered better tendon handling. The 3D-model improved visualization of suture placement. Both models were equally accepted and recommended for training. ConclusionThe 3D-printed silicone tendon model is a cost-effective and reproducible alternative to porcine models in flexor tendon repair training. Although the 3D-printed model has limitations in mimicking human tendons, it was equally effective in teaching suturing techniques and improving repair skills. Combining the porcine model and 3D-printed model provides a comprehensive approach to flexor tendon repair training, addressing the limitations of each model and enhancing the educational experience.

Comparison of Outcome Between Early and Delayed Repair of Flexor Tendons

Comparison of Outcome Between Early and Delayed Repair of Flexor Tendons

Mesenchymal Stromal Cells for the Enhancement of Surgical Flexor Tendon Repair in Animal Models: A Systematic Review and Meta-Analysis.

Flexor tendon lacerations are primarily treated by surgical repair. Limited intrinsic healing ability means the repair site can remain weak. Furthermore, adhesion formation may reduce range of motion post-operatively. Mesenchymal stromal cells (MSCs) have been trialled for repair and regeneration of multiple musculoskeletal structures. Our goal was to determine the efficacy of MSCs in enhancing the biomechanical properties of surgically repaired flexor tendons. A PRISMA systematic review was conducted using four databases (PubMed, Ovid, Web of Science, and CINAHL) to identify studies using MSCs to augment surgical repair of flexor tendon injuries in animals compared to surgical repair alone. Nine studies were included, which investigated either bone marrow- or adipose-derived MSCs. Results of biomechanical testing were extracted and meta-analyses were performed regarding the maximum load, friction and properties relating to viscoelastic behaviour. There was no significant difference in maximum load at final follow-up. However, friction, a surrogate measure of adhesions, was significantly reduced following the application of MSCs (p = 0.04). Other properties showed variable results and dissipation of the therapeutic benefits of MSCs over time. In conclusion, MSCs reduce adhesion formation following tendon injury. This may result from their immunomodulatory function, dampening the inflammatory response. However, this may come at the cost of favourable healing which will restore the tendon's viscoelastic properties. The short duration of some improvements may reflect MSCs' limited survival or poor retention. Further investigation is needed to clarify the effect of MSC therapy and optimise its duration of action.

The effect of the number of strands and knot throws of core suture techniques on the mechanical properties of the repaired flexor tendon.

Flexor tendon injury is a common hand trauma that requires surgical repair. The objective was to compare the repaired strength and gliding resistance with a varied number of repair strands and of square knots using a two-strand-overhand locking (TSOL) knot. First, isolated suture loops with different number of suture strands and number of closing knots were compared in mechanical strength and failure mode. Then, 90 flexor digitorum profundus (FDP) tendons from turkey digits were used for the tendon repair experiment. Both phases followed a similar 3 × 3 matrix comparing the knot type including TSOL+1SK (square knot), TSOL+2SK, and TSOL+3 SK and repair techniques including two-, four-, and six-strand repairs techniques respectively. The repaired tendons were tested for tendon resistance against pulley (friction), maximum force, force at 2 mm displacement, stiffness, and failure mode. Increasing the number of strands and closing square knots increases the tensile strength and stiffness of flexor tendon repairs and isolated suture loops without a significant effect on tendon friction. An increase in the number of square knots have shown increased strength only in Pennington repair, which correlated with the increased number of knot unraveling, a weak knot failure model. Our data demonstrated that increasing the number of strands is effective for improving the overall strength of tendon repair. When a two-strand repair is chosen, increasing knot number can improve repair strength. However, the number of knots appears not affecting repair strength in six-strand repair technique.

Current trends in the prevention of adhesions after zone 2 flexor tendon repair.

Treating flexor tendon injuries within the digital flexor sheath (commonly referred to as palmar hand zone 2) presents both technical and logistical challenges. Success hinges on striking a delicate balance between safeguarding the surgical repair for tendon healing and initiating early rehabilitation to mitigate the formation of tendon adhesions. Adhesions between tendon slips and between tendons and the flexor sheath impede tendon movement, leading to postoperative stiffness and functional impairment. While current approaches to flexor tendon repair prioritize maximizing tendon strength for early mobilization and adhesion prevention, factors such as pain, swelling, and patient compliance may impede postoperative rehabilitation efforts. Moreover, premature mobilization could risk repair failure, necessitating additional surgical interventions. Pharmacological agents offer a potential avenue for minimizing inflammation and reducing adhesion formation while still promoting normal tendon healing. Although some systemic and local agents have shown promising results in animal studies, their clinical efficacy remains uncertain. Limitations in these studies include the relevance of chosen animal models to human populations and the adequacy of tools and measurement techniques in accurately assessing the impact of adhesions. This article provides an overview of the clinical challenges associated with flexor tendon injuries, discusses current on- and off-label agents aimed at minimizing adhesion formation, and examines investigational models designed to study adhesion reduction after intra-synovial flexor tendon repair. Understanding the clinical problem and experimental models may serve as a catalyst for future research aimed at addressing intra-synovial tendon adhesions following zone 2 flexor tendon repair.