Complications after flexor tendon repair: a systematic review and meta-analysis

Revision of Flexor Tendon Repair: Factors Associated With Flexor Tenolysis

BACKGROUND

Tenolysis restores mobility to the flexor tendon through the lysis of adhesions that inhibit and negatively impact functional outcomes following flexor tendon repair. Despite extensive literature on operative techniques and therapy protocols used to minimize adhesion formation, there are limited data examining the association of patient, injury, and postoperative factors with tenolysis. This study aims to: (1) quantify tenolysis rates following flexor tendon repair or reconstruction; and (2) identify patient demographic factors, medical comorbidities, injury characteristics, postoperative diagnoses, and complications associated with tenolysis.

METHODS

PearlDiver was used to identify patients who underwent a flexor tendon repair or reconstruction from 2010 to 2020. Patients were stratified by whether or not flexor tenolysis was performed. Patient demographics, comorbidities, injury characteristics, postoperative diagnoses, and complications were recorded. Logistic regression analysis was used to identify independent risk factors associated with tenolysis.

RESULTS

Database review identified 10 264 patients who underwent either flexor tendon repair or reconstruction, with 612 patients (6.0%) subsequently undergoing tenolysis. Logistic regression analysis determined that vascular injury preceding flexor tendon repair, surgical wound disruption, nerve injury diagnosed postoperatively, postoperative tendon rupture, and need for repeat flexor tendon repair were associated with an increased odds of tenolysis. Patient age, sex, and comorbidities were not associated with performance of tenolysis.

CONCLUSIONS

Although tenolysis rates may differ according to physician and patient preferences, identification of factors associated with tenolysis following flexor tendon repair allows surgeons to risk-stratify patients prior to surgery and help guide postoperative expectations if complications arise.

Mental and behavioural disorders increase the risk of tendon rupture after flexor tendon repair in zone I and II

Introduction

The effect of mental and behavioural disorders (MBD) on the risk of tendon ruptures after flexor tendon repair is not well understood. This study aimed to analyse the association between MBD and tendon rupture after flexor tendon repair in zones I and II.

Methods

Data from the Swedish National Registry for Hand Surgery (HAKIR) on patients with a complete flexor tendon repair at our department between 2012 and 2019 were followed for a minimum of 2 years to assess the rate of rupture. Independent variables were collected from HAKIR and clinical records: prevalence MBD based on ICD-10 codes F0-F99, age, sex, injured tendon, number of injured fingers, day to surgery, core suture, digital nerve injury, smoking, injury mechanism, and rehabilitation method. Multiple logistic regression was used to assess the association between variables.

Results

A cohort of 593 patients with 49 ruptures (8.2%) was identified. Potential causes of rupture were non-adherence behaviour in 16 (33%), accidents in seven (14%), infections in six (12%), and no clear cause in 20 (41%) patients. Patients with MBD had an association to rupture (OR 3.6), 17.7% ruptures compared to 7.2% in patients with no diagnosed disorders. Patients >50 years of age had a higher risk compared to patients <25 years (OR 4.3), 15% compared to 3.9%' respectively. Men had a higher risk compared to women (OR 2.9), 10% compared to 4.3%' respectively.

Conclusion

We identified an association between the prevalence of mental and behavioural disorders and rupture after flexor tendon repair.

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.

Construct validation of a novel synthetic tendon model used for assessing surgeon performance in a simulated core suture tendon repair technique

BACKGROUND

The strength of tendon repair is dependent on the quality of the core suture. Organic and synthetic materials have been used to simulate tendon repair for training; however, no model has undergone construct validation.

OBJECTIVES

To determine the construct validity of a novel synthetic tendon repair model.

METHODS

Synthetic silicone tendon models were used to simulate adult Achilles tendon (AT) and digital flexor tendon (FT). Participants were categorised into novice, intermediate, and advanced groups based on prior surgical experience. Participants repaired tendons using the modified Kessler technique. A validated motion analysis system was used to measure the duration, path length, and movement count during the simulated task. A global rating score was also used to assess the performance.

RESULTS

All participants in the novice (n = 12), intermediate (n = 8) and advanced (n = 11) groups completed the tasks. The results (mean±standard deviation) were duration (872 ± 335, 492 ± 257 and 357 ± 40 s), path length (9493 ± 3173, 6668 ± 1740 and 4672 ± 1228 cm), movement count (4974 ± 673, 4228 ± 259 and 3962 ± 69) and global rating (39 ± 13, 61 ± 14, 81 ± 5), respectively. The Kruskal-Wallis test was significant for all outcome measures (p < 0.01). Significant differences in duration and movement count were identified post-hoc in the AT model for each experience group (p < 0.05), and between novice and intermediate participants for FT repair (p < 0.04). Global rating was significantly different between all groups and was highly correlated with motion metrics (p < 0.01).

CONCLUSION

The results support construct validity of this novel simulated tendon repair model. The global rating scores may allow wide utility of this simulation. This model provides a valid and safe environment for surgical trainees to practice tendon repair with several cost, ethical and logistical benefits over animal tendon use. 248/250.

Factors predicting the adhesion and prolonged lost days of work in patients with extensor tendon adhesion of the hand

Objective

Extensor tendon adhesion receive less attention recently. This study aims to analyze influencing factors of adhesion and prolonged lost days of work in patients with extensor tendon adhesion of the hand.

Method

We performed a retrospective study in patients with extensor tendon injuries who underwent primary surgical repair and early rehabilitation. We observed the differences between non-tendon adhesion and adhesion patients after surgical repair, and used the receiver operating characteristic curve to distinguish them. Then we explored the influencing factors of adhesion. In addition, we studied the lost days of work and the influencing factors.

Results

A total of 305 patients were included. 24.6% patients appeared tendon adhesion and the mean lost days of work was 12 weeks. MHISS scores, VAS scores, occupation and blood triglyceride level were the influencing factors of adhesion. The adhesion patients have increased MHISS scores (p < 0.001), VAS scores (p < 0.001), blood triglyceride levels (p < 0.001) and lost days of work (p < 0.001) than non-tendon adhesion. The optimal cut-off value of blood triglyceride level to distinguish non-tendon adhesion from adhesion was 1.625 mml/L, and MHISS scores was 20.5. Smoking, MHISS scores, blood triglyceride levels were the influencing factors of lost days of work in adhesion patients. There was positive correlation between lost days of work and triglyceride level (r = 0.307, p = 0.007), and MHISS scores (r = 0.276, p = 0.016).

Conclusion

To minimize the occurrence of adhesion, doctors should pay attention to patients with higher MHISS and VAS scores, blood triglyceride levels, especial for the blue-collar and unemployed one. High triglyceride level may be a new influencing factor.

Complications and side effects of Wide-Awake Local Anaesthesia No Tourniquet (WALANT) in upper limb surgery: a systematic review and meta-analysis

PURPOSE

Wide-Awake Local Anaesthesia No Tourniquet (WALANT), a groundbreaking anaesthetic technique resurging in practice, warrants a comprehensive safety analysis for informed adoption. Our study aimed to identify complications/side effects of WALANT upper limb procedures through a systematic review and meta-analysis.

METHODS

This PROSPERO-registered study was performed with strict adherence to PRISMA guidelines. Embase, OVIDMedline, Cochrane, Web of Science, and Scopus databases were searched until February 2023. Inclusion criteria involved English articles, reporting complications/side effects in primary WALANT upper limb surgeries. Outcomes included all complications and side effects, data on the anaesthetic mixture, publication year/location, study type, and procedures performed. The meta-analysis employed the Freeman-Tukey Double Arcsine Transformation, computed I2 statistics, and utilized common or random effects models for pooled analysis.

RESULTS

2002 studies were identified; 79 studies met the inclusion criteria representing 15,595 WALANT patients. A total of 301 patients had complications, and the meta-analysis using a random effects model provided a complication rate of 1.7% (95% CI: 0.93-2.7%). The most reported complications were superficial infection (41%, n = 123/300), other/specified (12%, n = 37/300), and recurrent disease (6.7%, n = 20/300). A decade-by-decade analysis revealed no statistically significant difference in complication rates spanning the last three decades (p = 0.42). Adding sodium bicarbonate to the anaesthetic solution significantly reduced postoperative complications (p = 0.025).

CONCLUSION

WALANT has a low overall complication rate of 1.7%, with no significant temporal variation and a significant reduction in complications when sodium bicarbonate is added to the anaesthetic solution. Our findings support the safety of WALANT in upper limb procedures.

REGISTRATION

PROSPERO: CRD42023404018.

Diamond-Like Carbon Depositing on the Surface of Polylactide Membrane for Prevention of Adhesion Formation During Tendon Repair

Post-traumatic peritendinous adhesion presents a significant challenge in clinical medicine. This study proposes the use of diamond-like carbon (DLC) deposited on polylactic acid (PLA) membranes as a biophysical mechanism for anti-adhesion barrier to encase ruptured tendons in tendon-injured rats. The results indicate that PLA/DLC composite membrane exhibits more efficient anti-adhesion effect than PLA membrane, with histological score decreasing from 3.12 ± 0.27 to 2.20 ± 0.22 and anti-adhesion effectiveness increasing from 21.61% to 44.72%. Mechanistically, the abundant C=O bond functional groups on the surface of DLC can reduce reactive oxygen species level effectively; thus, the phosphorylation of NF-κB and M1 polarization of macrophages are inhibited. Consequently, excessive inflammatory response augmented by M1 macrophage-originated cytokines including interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) is largely reduced. For biocompatibility evaluation, PLA/DLC membrane is slowly absorbed within tissue and displays prolonged barrier effects compared to traditional PLA membranes. Further studies show the DLC depositing decelerates the release of degradation product lactic acid and its induction of macrophage M2 polarization by interfering esterase and PLA ester bonds, which further delays the fibrosis process. It was found that the PLA/DLC membrane possess an efficient biophysical mechanism for treatment of peritendinous adhesion.

Diagnosis and treatment of flexor tendon injuries of the hand: what the radiologist needs to know

This article reviews the diagnosis and treatment of flexor tendon injuries of the hand highlighting flexor tendon anatomy, important pre-operative imaging findings, surgical options, and post-operative complications. Imaging plays a key role in guiding treatment of these difficult to manage injuries. Thus, it is important for radiologists to have a sound understanding of factors important in treatment decision-making. In the pre-operative setting, accurately identifying the location of the torn proximal tendon stump in subacute and chronic injuries helps dictate whether the patient is a candidate for a primary flexor tendon repair or may require a tendon reconstruction to restore function. In the post-operative setting, the status of the repair and presence of surrounding adhesions help dictate if and when the patient will require subsequent surgery and whether that surgery will be a tenolysis, revision repair, reconstruction, or fusion.

Effects of evidence-based nursing care interventions on wound pain and wound complications following surgery for finger tendon injury

We conducted this study aimed to examine the impact of evidence-based nursing interventions on postoperative wound pain and complications after surgery for finger tendon injury. A total of 86 patients treated for finger tendon injuries at our hospital from January 2021 to October 2023 were selected and randomly divided into an experimental group and a control group. The control group received conventional nursing care, while the experimental group received evidence-based nursing interventions. The study compared the postoperative wound pain intensity, incidence of complications and patient satisfaction with nursing care between the two groups. The analysis revealed that compared with conventional care, evidence-based nursing interventions significantly reduced the level of wound pain (p = 0.034) and the incidence of complications (4.65% vs. 18.60%, p = 0.043). It also increased patient satisfaction with the nursing care (97.67% vs. 83.72%, p = 0.026). The study indicates that the application of evidence-based nursing interventions for patients with finger tendon injuries can reduce postoperative wound pain, decrease the incidence of complications and enhance patient satisfaction with nursing care.

Current clinical opinion on surgical approaches and rehabilitation of hand flexor tendon injury-a questionnaire study

The management of flexor tendon injury has seen many iterations over the years, but more substantial innovations in practice have been sadly lacking. The aim of this study was to investigate the current practice of flexor tendon injury management, and variation in practice from the previous reports, most troublesome complications, and whether there was a clinical interest in potential innovative tendon repair technologies. An online survey was distributed via the British Society for Surgery of the Hand (BSSH) and a total of 132 responses were collected anonymously. Results showed that although most surgeons followed the current medical recommendation based on the literature, a significant number of surgeons still employed more conventional treatments in clinic, such as general anesthesia, ineffective tendon retrieval techniques, and passive rehabilitation. Complications including adhesion formation and re-rupture remained persistent. The interest in new approaches such as use of minimally invasive instruments, biodegradable materials and additive manufactured devices was not strong, however the surgeons were potentially open to more effective and economic solutions.

Complications of flexor tendon repair

This article reviews and highlights complications of flexor tendon repairs. Although the outcomes of flexor tendon repairs have improved over the years, fair or poor functional outcomes are seen, especially in patients whose trauma involves multiple structures of the hand and in zone 5 with multiple tendon lacerations. Rupture of the flexor tendon after repair is no longer a major problem if current repair principles are carefully adhered to. Different degrees of adhesion formations and interphalangeal (IP) joint stiffness still occur in a few patients. Early active postoperative mobilization and use of a shorter splint with sparing of the wrist are effective measures to prevent adhesion formation and IP joint stiffness. Given the overall poor results and high rate of complications with flexor digitorum profundus (FDP) repairs in zone 1, a direct repair of the FDP tendon to any short remnant of the distal insertion with 10-strand or even stronger core suture repair is adopted by many units.

Cell Sheet Technology: An Emerging Approach for Tendon and Ligament Tissue Engineering

Tendon and ligament injuries account for a substantial proportion of disorders in the musculoskeletal system. While non-operative and operative treatment strategies have advanced, the restoration of native tendon and ligament structures after injury is still challenging due to its innate limited regenerative ability. Cell sheet technology is an innovative tool for tissue fabrication and cell transplantation in regenerative medicine. In this review, we first summarize different harvesting procedures and advantages of cell sheet technology, which preserves intact cell-to-cell connections and extracellular matrix. We then describe the recent progress of cell sheet technology from preclinical studies, focusing on the application of stem cell-derived sheets in treating tendon and ligament injuries, as well as highlighting its effects on mitigating inflammation and promoting tendon/graft-bone interface healing. Finally, we discuss several prerequisites for future clinical translation including the selection of appropriate cell source, optimization of preparation process, establishment of suitable animal model, and the fabrication of vascularized complex tissue. We believe this review could potentially provoke new ideas and drive the development of more functional biomimetic tissues using cell sheet technology to meet the needs of clinical patients.

Minimally Invasive Suture Technique Pull-out to Repair the Acute Flexor Tendons in Zone II of the Hand

Objective:  To evaluate the safety and effectiveness of a modified pull-out suture technique in patients undergoing primary repair surgery for injuries to the flexor tendons of the fingers with Total Active Motion (TAM) as the primary outcome. Method:  A total of 29 patients (38 fingers) were chosen from both sexes, aged between 18 and 65 years with clean acute tendon laceration occurring within 15 days, in the Verdan's zone II of flexor tendon in the hand, when only the deep flexor tendon was sutured, either associated or not with digital nerve injury. The patients were operated on using the proposed technique and evaluated at 3, 9 and 24-weeks PO. The primary outcome was the assessment of Total Active Movement (TAM) and 3 classifications were employed: Strickland, IFSSH and Buck-Gramcko. Results:  We observed a total active motion (TAM) of 209.3 °at the end of 24 weeks; 83.0% of Good and Excellent results by the Modified Strickland Classification, 93% of Excellent results by the IFSSH Classification, and 97% of Good and Excellent results using the Buck-Gramcko Classification. There were no cases of rupture, but tendon adhesion was observed in 3 fingers. Conclusion:  The present suture technique proved to be safe and effective with a low rate of complications, obtaining an excellent functional result in terms of total active mobility, according to the evaluations and classifications used.

Pre- and post-treatment in flexor tendon tenolysis: An observational study

BACKGROUND

Glide deficit of the distal flexors' tendons following primary repair in zone 1-3 are very common. Adhesions of tendons have multi factorial origins and are closely related to the healing of the affected tissues. The surgical practice used to resolve these complications is tenolysis.

PURPOSE

The purpose of this study was to identify and compare the Visual Analog Scale (VAS) relate to pain and Total Active Motion (TAM) of adult patients of both sexes undergoing tenolysis surgery. The results will then be compared to existing research to confirm their significance.

STUDY DESIGN

Case-series.

METHODS

Retrospective data for TAM and pain VAS were extracted from the medical records for 63 patients (73 fingers) who underwent flexor tenolysis between 2017 and 2019. Data were compared pre-operatively and 3 months after surgery. All patients underwent pre- and post-surgery therapy by hand therapists.

RESULTS

The sample presented very encouraging improvements, except in the VAS and active range of motion (AROM) of thumb where some patients maintained the same assessment. The fingers reported statistically significant results, whereas the thumb group did not meet significant criteria. Overall, TAM improved from 134.6° to 196.7 and VAS decreased from 2.7 to 1.2.

DISCUSSION

According to the results and the data change between pre- and post-treatment, the sample demonstrated improvements in all areas examined, reporting statistically significant results for the fingers with an improvement of TAM of 62.1° with a percentage value (%TAM) of 75.6%.

CONCLUSIONS

A specific treatment for this type of surgery is required for the patients so they can return to their daily and working activities. This article can be used as a starting point for further studies.

Short-Term and Long-Term Therapeutic Results of Deep Flexor Tendon Repair in Zone II in Patients Referred to Imam Khomeini Hospital, Ahvaz, Southern Iran

Background

Hand injury as an important concern for the surgeon and the patient requires proper and timely treatment to prevent complications such as infection and adhesions, and with a proper rehabilitation program, the patient returns to maximum function as soon as possible. We aimed to investigate the short-term and long-term treatment results of deep flexor tendon repair in in zone II.

Methods

This retrospective study was performed on 34 patients with 45 injured fingers in the zone II referred to Ahvaz Imam Khomeini Hospital, Ahvaz, Iran during 2017-2019. The results of deep flexor tendons repair in two groups, immediate and delayed primary repair were assessed.

Results

The mean age of the patients was 27.76 years. There was no significant remarkable between male and female in the incidence of complications such as infection, tendon rupture and adhesions. 29.4% (n=10) had poor outcome, 8.8% (n=3) had fair outcome, 29.4% (n=10) had good outcome and 32.4% (n=11) had excellent outcomes. 26.5% had adhesion and infection rate was 11.8%.

Conclusion

Among surgeons, there is consensus for the primary repair of tendon injury, but there was no significant difference between the results of immediate and delayed primary repair. Although physiotherapy has been suggested as an effective factor in improving hand function, its positive effect on the range of motion of the fingers has not been proven.

Multilayer amnion-PCL nanofibrous membrane loaded with celecoxib exerts a therapeutic effect against tendon adhesion by improving the inflammatory microenvironment

Tendon adhesion is a common complication after tendon surgery. The inflammatory phase of tendon healing is characterized by the release of a large number of inflammatory factors, whose mediated excessive inflammatory response is an important cause of tendon adhesion formation. Nonsteroidal anti-inflammatory drugs(NSAIDs) were used to prevent tendon adhesions by reducing the inflammatory response. However, recent studies have shown that the NSAIDs partially impairs tendon healing. Therefore, optimizing the anti-adhesive membrane loaded with NSAIDs to mitigate the effects on tendon healing requires further in-depth study. Amniotic membranes(AM) are natural polymeric semi-permeable membranes from living organisms that are rich in matrix, growth factors, and other active ingredients. In this study, we used electrostatic spinning technology to construct multifunctional nanofiber membranes of the PCL membrane loaded with celecoxib and AM. In vitro cellular assays revealed that celecoxib-loaded PCL membranes significantly inhibited the adhesion and proliferation of fibroblasts with increasing concentrations of celecoxib. In a rabbit tendon repair model, biomechanical tests further confirmed that the PCL membrane loaded with celecoxib had better anti-adhesion effects. Further experimental studies revealed that the PCL/AM membrane improved the inflammatory microenvironment by downregulating the expression of pro-inflammatory factors such as COX-2, IL-1β, and TNF-α proteins; and inhibiting the synthesis of COL I and COL Ⅲ. The PCL/AM membrane can continuously release celecoxib to reduce the inflammatory response and deliver growth factors to the damaged area to build a suitable microenvironment for tendon repair, which provides a new direction to improve the repair efficiency of tendon.

Comparison of pulley plasty, pulley venting and resection of flexor digitorum superficialis slip after zone II flexor tendon repair: a cadaver study

LEVEL OF EVIDENCE

V.

Current and future utility of ultrasound imaging in upper extremity musculoskeletal rehabilitation: A scoping review

STUDY DESIGN

This study was a scoping review.

BACKGROUND

Continued advances in musculoskeletal sonography technology and access have increased the feasibility of point-of-care use to support day-to-day clinical care and decision-making. Sonography can help improve therapeutic outcomes in upper extremity (UE) rehabilitation by enabling clinicians to visualize underlying structures during treatment.

PURPOSE OF THE STUDY

This study aimed to (1) evaluate the growth, range, extent, and composition of sonography literature supporting UE rehabilitation; (2) identify trends, gaps, and opportunities with regard to anatomic areas and diagnoses examined and ultrasound techniques used; and (3) evaluate potential research and practice utility.

METHODS

Searches were completed in PubMed, CINAHL, SPORTDiscus, PsycINFO, and BIOSIS. We included data-driven articles using ultrasound imaging for upper extremity structures in rehabilitation-related conditions. Articles directly applicable to UE rehabilitation were labeled direct articles, while those requiring translation were labeled indirect articles. Articles were further categorized by ultrasound imaging purpose. Article content between the two groups was descriptively compared, and direct articles underwent an evaluation of evidence levels and narrative synthesis to explore potential clinical utility.

RESULTS

Average publication rates for the final included articles (n = 337) steadily increased. Indirect articles (n = 288) used sonography to explore condition etiology, assess measurement properties, inform medical procedure choice, and grade condition severity. Direct articles (n = 49) used sonography to assess outcomes, inform clinical reasoning, and aid intervention delivery. Acute UE conditions and emerging sonography technology were rarely examined, while tendon, muscle, and soft tissue conditions and grayscale imaging were common. Rheumatic and peripheral nerve conditions and Doppler imaging were more prevalent in indirect than direct articles. Among reported sonography service providers, there was a high proportion of nonradiologist clinicians.

CONCLUSION

Sonography literature for UE rehabilitation demonstrates potential utility in evaluating outcomes, informing clinical reasoning, and assisting intervention delivery. A large peripheral knowledge base provides opportunities for clinical applications; however, further research is needed to determine clinical efficacy and impact for specific applications.

Flexor Tendon Zone II Repair

Background

Flexor-tendon injury is a historically challenging problem for orthopaedic surgeons. Much research has been dedicated to finding solutions that offer balance in terms of the strength and ease of the repair versus the rate of complications such as adhesions. The number of core sutures, distance from the tendon edge, and use of an epitendinous stitch have been shown to affect repair strength1-4. A number of configurations have been described for the placement of the suture; however, none has been identified as a clear gold standard5. This article will highlight the preferred tendon repair technique of the senior author (R.J.S.), the Strickland repair with a simple running epitendinous stitch. Relevant anatomy, indications, operative technique, and postoperative management will be discussed.

Description

The flexor tendon is typically accessed via extension of the laceration that caused the initial injury. After the neurovascular structures and pulleys are assessed, the tendon is cleaned and prepared for repair. A 3-0 braided nylon suture is utilized for the 4-core strand repair and placed in the Strickland fashion. A 5-0 polypropylene suture is then utilized for the simple running epitendinous stitch.

Alternatives

Multiple alternative techniques have been described. These vary in the number of core strands, the repair configuration, the suture caliber, and the use of an epitendinous or other suture. Nonoperative treatment is typically reserved for partial flexor-tendon laceration, as complete tendon discontinuity will not heal and requires surgical intervention.

Rationale

The 4-core strand configuration has been well established to increase the strength of the repair as compared with 2-core strand configurations, while also being easier to accomplish and with less suture burden than other techniques1. The presently described technique has excellent repair strength and can allow for early active range of motion, which is critical to reduce the risk of postoperative adhesions and stiffness.

Expected Outcomes

Excellent outcomes have been demonstrated for primary flexor-tendon repair if performed soon after the injury1,2,6,7. Delayed repair may lead to adhesions and poor tendon healing8. Early postoperative rehabilitation is vital for success9. There are advocates for either active or passive protocols10-12. The protocol at our institution is to begin early active place-and-hold therapy at 3 to 5 days postoperatively, which has been shown in the literature to provide improved finger motion as compared with passive-motion therapy13-16.Important Tips:: The proximal end of the tendon may need to be retrieved via a separate incision if it is not accessible through the flexor-tendon sheath.The proximal end of the tendon may be held in place with a 25-gauge needle in order to best place sutures into both ends of the tendon.The epitendinous suture is run around the back wall before the core sutures are tied down, in order to prevent the tendon and repair from bunching up and becoming overly bulky.The entire A4 pulley and the distal A2 pulley can be divided for exposure if necessary.Up to 2 cm of the flexor-tendon sheath can be divided.If there are concomitant digital nerve injuries, repair these after the tendon, in order to avoid damaging the more delicate nerve repair while manipulating the tendon for repair.The most common major complications following tendon repair are formation of adhesions and rerupture. Acronyms and Abbreviations:: FDS = flexor digitorum superficialisFDP = flexor digitorum profundusMCP = metacarpophalangealPIP = proximal interphalangealDIP = distal interphalangeal.

Relative efficacy of three different tendon repairs in complete flexor digitorum profundus laceration in Zone I: A randomized controlled study

Hand flexor tendon injuries are common and biomechanically challenging to achieve good functional outcomes. Several approaches using the Pennington-modified Kessler repair technique have been attempted, but high-level evidence is still lacking. Here, we evaluated the relative efficacy of three versions of the Pennington-modified Kessler technique in repairing complete flexor digitorum profundus (FDP) laceration in Zone 1. We conducted a 2-year, single-center, double-blind, randomized clinical trial involving 85 patients with 105 digits enrolled between June 1, 2017 and January 1, 2019. Eligible participants were 20-60 years of age and underwent tendon repair in the acute phase for complete FDP laceration distal to the insertion of the superficial flexor tendon. The digits were randomized 1:1:1 to three treatment groups: (1) Pennington-modified Kessler repair; (2) Pennington-modified Kessler repair followed by circumferential tendon suture; or (3) Pennington-modified Kessler repair followed by circumferential epitenon suture. The primary endpoint was total active range of motion (TAROM) at 2 years after the initial surgery. The secondary endpoint was the reoperation rate. Compared with group 1, both techniques for peripheral suture were associated with a decrease in TAROM at 2 years after surgery. The total reoperation rates of the three groups were 11.4%, 18.2%, and 17.6%, and we found no significant differences among the three groups possibly due to the limited sample size. Unexpectedly, among participants with complete FDP laceration in Zone I, both circumferential-tendon and circumferential-epitenon sutures caused worsening of TAROM after 2 years. No conclusions can be drawn regarding reoperation rates among the groups. Level of evidence: Therapeutic level I.

Reoperation Following Zone II Flexor Tendon Repair

BACKGROUND

The goal of zone II flexor tendon surgery is to perform a repair with sufficient strength to withstand the forces encountered during rehabilitation. Postoperative rerupture and adhesion formation may lead to reoperation. This study aimed to determine the factors associated with reoperation after primary zone II flexor tendon repair.

METHODS

In this retrospective case series, a total of 252 fingers in 201 patients underwent zone II flexor tendon repair. A medical record review was performed to collect data regarding patient demographics, injury and treatment characteristics and postoperative complications including reoperation. Reoperation was defined as any unplanned surgical procedure performed after initial flexor tendon repair.

RESULTS

There were 49 fingers (19%) in 42 patients that underwent reoperation at a median of 5.5 (interquartile range: 2.8-7.9) months. Older age, workers' compensation, and a Kessler-type repair of the flexor digitorum profundus were independently associated with reoperation.

CONCLUSIONS

In vitro studies suggest that Kessler-type repairs are inferior compared with other suture configurations. Our study demonstrates a clinical correlation to these biomechanical studies. Our results suggest that Kessler-type repairs are inferior compared with non-Kessler-type repairs, due to postoperative complications requiring secondary surgeries.

Flexor Tendon Repair: Avoidance and Management of Complications

The proper technique for flexor tendon repair has been well established through numerous bench science and clinical studies. However, less is known about strategies to avoid and manage postoperative complications. This article discusses the common complications after flexor tendon repair, such as repair site rupture and adhesion formation. This article also addresses strategies to prevent and manage these complications. The foundation for preventing many of these complications is ensuring a strong repair without gapping at time zero, which will enable the accrual of tensile strength through early initiation of motion.

Metformin suppressed tendon injury-induced adhesion via hydrogel-nanoparticle sustained-release system

Tendon adhesion is one of the sequelae of tendon injury and can lead to disability in severe cases. Metformin is a commonly used antidiabetic drug. Some studies had shown that metformin could reduce tendon adhesion as well. Considering the characteristic of low absorption rate and short half-life, we established a sustained-release system, i.e., hydrogel-nanoparticle system to deliver metformin. In vitro, metformin could effectively suppress TGF-β1-induced cell proliferation and accelerate cell apoptosis, according to cell counting kit-8, flow cytometry, and 5-ethynyl-2'-deoxyuridine (EdU) staining studies. In vivo, hydrogel-nanoparticle/metformin system could significantly lower adhesion scores and improve the gliding function of repaired flexor tendons, as well as decrease the expression of fibrotic proteins Col1a1, Col3a1, and α-smooth muscle actin (α-SMA). Histological staining revealed that the inflammation had subsided and that the gap between the tendon and the surrounding tissue was wider in the hydrogel-nanoparticle/metformin treatment group. Finally, we speculated that effect of metformin on reducing tendon adhesion might be achieved by regulating both Smad and MAPK-TGF-β1 signaling pathways. In conclusion, metformin delivered through hydrogel-nanoparticle sustained-release system may be a promising strategy for coping with tendon adhesion.

Functional Outcomes of Flexor Tendon Repair in the Fingers: A Comparison of Wide-Awake Local Anesthesia No Tourniquet Versus Traditional Anesthesia

BACKGROUND

Flexor tendon lacerations in the fingers are challenging injuries that can be repaired using the wide-awake local anesthesia no tourniquet (WALANT) technique or under traditional anesthesia (TA). The purpose of our study was to compare the functional outcomes and complication rates of patients undergoing flexor tendon repair under WALANT versus TA.

METHODS

All patients who underwent a primary flexor tendon repair in zone I and II without tendon graft for closed avulsions or open lacerations between 2015 and 2019 were identified. Electronic medical records were reviewed to record and compare patient demographics, range of motion, functional outcomes, complications, and reoperations.

RESULTS

Sixty-five zone I (N = 21) or II (N = 44) flexor tendon repairs were included in the final analysis: 23 WALANT and 42 TA. There were no statistical differences in mean age, length of follow-up, proportion of injured digits, or zone of injury between the groups. The final Quick Disabilities of the Arm, Shoulder, and Hand score in the WALANT group was 17.2 (SD: 14.4) versus 23.3 (SD: 18.5) in the TA group. There were no statistical differences between the groups with any final range of motion (ROM) parameters, grip strength, or Visual Analog Scale pain scores at the final follow-up. The WALANT group was found to have a slightly higher reoperation rate (26.1% vs 7.1%; P = .034) than the TA group.

CONCLUSIONS

This study represents one of the first clinical studies reporting outcomes of flexor tendon repairs performed under WALANT. Overall, we found no difference in rupture rates, ROM, and functional outcomes following zone I and II flexor tendon repairs when performed under WALANT versus TA.

Neutralization of excessive levels of active TGF-β1 reduces MSC recruitment and differentiation to mitigate peritendinous adhesion

Peritendinous adhesion formation (PAF) can substantially limit the range of motion of digits. However, the origin of myofibroblasts in PAF tissues is still unclear. In this study, we found that the concentration of active TGF-β1 and the numbers of macrophages, mesenchymal stromal cells (MSCs), and myofibroblasts in human and mouse adhesion tissues were increased. Furthermore, knockout of TGF-β1 in macrophages or TGF-β1R2 in MSCs inhibited PAF by reducing MSC and myofibroblast infiltration and collagen I and III deposition, respectively. Moreover, we found that MSCs differentiated into myofibroblasts to form adhesion tissues. Systemic injection of the TGF-β-neutralizing antibody 1D11 during the granulation formation stage of PAF significantly reduced the infiltration of MSCs and myofibroblasts and, subsequently, PAF. These results suggest that macrophage-derived TGF-β1 recruits MSCs to form myofibroblasts in peritendinous adhesions. An improved understanding of PAF mechanisms could help identify a potential therapeutic strategy.

Surgical Considerations for Flexor Tendon Repair: Timing and Choice of Repair Technique and Rehabilitation

Flexor tendon injuries are common and occur mostly due to penetrating trauma. Surgical repair is required for complete tendon lacerations, and many techniques exist. This article reviews the principles of tendon structure, function, healing, and anatomy. Repair techniques are discussed in detail for each flexor tendon zone. Postoperative rehabilitation greatly influences outcomes, and several protocols are described.

Hand Flexor Tendon Repair: From Biology to Surgery and Rehabilitation

Tendon biology and anatomy are crucial to manage hand flexor tendon injuries, not only for surgical treatment but also for rehabilitation; surgeon and physical therapist have to choose zone by zone the best way to manage and restore the normal function of hand flexor tendons.

Flexor Tendon Reconstruction

Chronic injury to the flexor tendon system of the hand remains a challenging problem for the hand surgeon to treat. Both single- and two-stage techniques remain important in the reconstruction of the flexor tendon deficient digit. Modern advances include the use of allograft composites that aim to reduce the time and donor-site morbidity compared with conventional autograft techniques. Regardless of technique, restoring a gliding tendon-pulley system with a functional arc of motion is the primary goal of flexor tendon reconstruction.

Tenolysis and Salvage Procedures

Complications in flexor tendon repair are common and include tendon rupture, adhesion formation, and joint contracture. Risk factors include preexisting conditions, gross contamination, concurrent fracture, early unplanned loading of the repaired tendon, premature cessation of splinting, and aggressive early active range of motion protocols with insufficient repair strength. Rupture of a repaired tendon should be followed by early operative exploration, debridement, and revision with a four-core strand suture and nonbraided epitendinous suture. Wide-awake flexor tenolysis should be considered when adhesion formation results in the plateaued range of motion, and passive motion exceeds active motion. Two-staged reconstruction is recommended when injury results in excessive scaring, joint contracture, or an incompetent pulley apparatus.

General Principles of Flexor Tendon Repair

Flexor tendon repair techniques and rehabilitation have advanced tremendously in the past 50 years. However, the attributes of the ideal tendon repair articulated by Dr Strickland in 1995 hold true today. The ideal repair requires sutures easily placed in the tendon, secure suture knots, a smooth juncture of the tendon ends, minimal gapping, least interference with tendon vascularity, and sufficient strength throughout healing. When accomplished, the modern flexor tendon repair is a stout repair, sufficient for early mobilization and intrinsic tendon healing.

Ex Vivo Biomechanical Assessment of Various Repair Techniques in a Rabbit Calcaneal Tendon Avulsion Model: Application of Polycaprolactone Plate

This study was aimed at evaluating the biomechanical properties and gapping characteristics of tendon repair methods using a combination of a three-loop pulley (3LP) pattern, a titanium plate, and a polycaprolactone (PCL) plate in a rabbit gastrocnemius tendon (GT) model (n = 50). GTs were randomly assigned to five groups (n = 10/group). Transected GTs were repaired with a 3LP pattern alone or in conjunction with an epitendinous suture (ES), a 5-hole 1 mm PCL plate, a 5-hole 2 mm PCL plate, or a 5-hole 1.5 mm titanium plate. The yield, peak, and failure force, as well as the occurrence and force of 1-mm and 3-mm gapping were examined. The mean yield, peak, and failure force of the 3LP + titanium plate group were higher than that of other groups. The biomechanical properties of a 3LP + a 2 mm PCL plate were similar to 3LP + ES constructs in this model. In all specimens in all groups, 1 mm gap formation was observed. The frequency of 3 mm gap formation was 70% and 90% in the 3LP + 2 mm PCL plate group and the 3LP + 1.5 mm titanium plate group, respectively. Additional studies evaluating PCL plates to determine the effect on the healing and blood supply of tendon are needed.

Patients' experiences of flexor tendon rehabilitation in relation to adherence: a qualitative study

PURPOSE

To explore patients' experiences of early active motion flexor tendon rehabilitation in relation to adherence to restrictions and outcome of rehabilitation.

METHOD

Seventeen patients with a flexor tendon injury in one or several fingers participated in qualitative interviews performed between 74 and 111 days after surgery. Data were analysed using directed content analysis with the Health Belief Model (HBM) as a theoretical framework.

RESULTS

Perceived severity of hand function and susceptibility to loss of hand function affected the participants' behaviour. A higher perceived threat increased motivation to exercise and be cautious in activities. During rehabilitation, the perceived benefits or efficacy of doing exercise and following restrictions were compared to the cost of doing so, leading to adherence or non-adherence behaviour. Perceived self-efficacy was affected by previous knowledge and varied through the rehabilitation period. External factors and interaction with therapists influenced the perception of the severity of the injury and the cost and benefits of adhering to rehabilitation.

CONCLUSION

Patient's perception of the injury, the effectiveness of exercises, context and social support to manage daily life affected adherence to restriction, motivation and commitment to rehabilitation. The HBM as a theoretical framework can be beneficial for understanding factors that influence patients' adherence.Implications for RehabilitationInformation regarding the injury and consequences for the patient should be presented at different time points and in different ways, tailored to the patient.It' is important to aid patients to perceive the small gradual improvements in hand function to create motivation to adhere to exercise.Strategies to reduce the cost of adherence in terms of managing everyday life should be addressed by individually based strategies.Instructions regarding exercise and restrictions should be less complex and consider the patient's individual needs.

Relative motion flexion following zone I-III flexor tendon repair: Concepts, evidence and practice

STUDY DESIGN

Narrative review and case series.

INTRODUCTION

The relative motion approach has been applied to rehabilitation following flexor tendon repair. Positioning the affected finger(s) in relatively more metacarpophalangeal joint flexion is hypothesized to reduce the tension through the repaired flexor digitorum profundus by the quadriga effect. It is also hypothesized that altered patterns of co-contraction and co-inhibition may further reduce flexor digitorum profundus tension, and confer protection to flexor digitorum superficialis.

METHODS

We reviewed the existing literature to explore the rationale for using relative motion flexion orthoses as an early active mobilization strategy for patients after zone I-III flexor tendon repairs. We used this approach within our own clinic for the rehabilitation of a series of patients presenting with zone I-II flexor tendon repair. We collected routine clinical and patient reported outcome data.

RESULTS

We report published outcomes of the clinical use of relative motion flexion orthoses with early active motion, implemented as the primary rehabilitation approach after zone I-III flexor digitorum repairs. We also report novel outcome data from 18 patients.

DISCUSSION

We discuss our own experience of using relative motion flexion as a rehabilitation strategy following flexor tendon repair. We explore orthosis fabrication, rehabilitation exercises and functional hand use.

CONCLUSIONS

There is currently limited evidence informing use of relative motion flexion orthoses following flexor tendon repair. We highlight key areas for future research and describe a current pragmatic randomized controlled trial.

Wide-Awake Local Anesthesia No Tourniquet (WALANT) for Flexor Tendon Repairs as Change in Practice During the COVID-19 Pandemic: A Retrospective Cohort Study With Outcomes

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic forced many changes. In our unit, there was a significant shift from traditional anesthesia (TA) which included general or regional anesthesia, to Wide-Awake Local Anesthesia No Tourniquet (WALANT) for the treatment of flexor tendon injuries. Zones I and II injuries have always been a challenge. The primary aim of this study is to compare the 12-week range of motion (ROM) flexor tendon repair outcomes between the TA group and wide-awake (WA) group patients. The secondary aim is to compare the complications and the follow-up rate between the two groups.

METHODS

All patients who underwent a primary finger flexor tendon repair in zone I or II without tendon graft for closed avulsions or open lacerations between April 2020 and March 2021 were included in the study. Electronic medical records were reviewed to record demographics, follow-up, ROM outcomes and complications.

RESULTS

Forty-four patients with 49 injured fingers were in the WA group, and 24 patients with 37 injured fingers were in the TA group. A complete follow-up with 12-week ROM outcomes was available for 15 patients with 16 injured fingers in the WA group and nine patients with 13 injured fingers in the TA group. Excellent to good outcomes in the WA group were reported in 56% of the cases versus 31% in the TA group, although the difference was not statistically significant. There were similar complications in both groups, with an overall rupture rate of 11.6%, a tenolysis rate of 3.5% and a reoperation rate of 9.3%. Complete 12-week follow-up was completed by 41% of patients overall after taking tendon ruptures into account.

CONCLUSIONS

This is one of the first studies comparing zones I and II flexor tendon ROM outcomes between WA anesthesia and TA. Overall, there was a trend toward superior ROM outcomes in the WA group, with similar complication rates in both groups. The difference between ROM outcomes was not statistically significant and the small sample size undermined the strength of the study. To provide stronger evidence, better-designed prospective studies are suggested that would compare WA techniques with TA techniques.

Clinical Outcomes After Aggressive Active Early Motion and Modified Kleinert Regimens: Comparison of 2 Consecutive Cohorts

BACKGROUND

Modern multistrand repairs can withstand forces present in active flexion exercises, and this may improve the outcomes of flexor tendon repairs. We developed a simple home-based exercise regimen with free wrist and intrinsic minus splint aimed at facilitating the gliding of the flexor tendons and compared the outcomes with the modified Kleinert regimen used previously in the same institution.

METHODS

We searched the hospital database to identify flexor tendon repair performed before and after the new regimen was implemented and invited all patients to participate. The primary outcome was total active range of motion, and secondary outcomes were Disabilities of Arm, Shoulder, and Hand; grip strength; globally perceived function; and the quality of life.

RESULTS

The active range of motion was comparable between the groups (mean difference = 14; 95% confidence interval [CI], -8 to 36; P = .22). Disabilities of Arm, Shoulder, and Hand; grip strength; global perceived function; and health-related quality of life were also comparable between the groups. There was 1 (5.3%) rupture in the modified Kleinert group and 4 (15.4%) in the early active motion group (relative risk = 0.3; 95% CI, 0.04-2.5; P = .3).

CONCLUSIONS

Increasing active gliding with a free wrist and intrinsic minus splint did not improve the clinical outcomes after flexor tendon injury at a mean of 38-month follow-up.

Long term functional outcome evaluation in post flexor digitorum profundus tendon zone I rupture repaired by palmaris longus tendon grafting augmented with human amniotic membranes and adipose derived mesenchymal stem cell: A case report

INTRODUCTION AND IMPORTANCE

The sport climbing has many complex maneuvers of the hand producing many potential injuries in flexor digitorum profundus tendon (FDPT). The late management due to an athlete high demand on competition makes the complication of retracted tendon and adhesion tend to occur. We provide the long terms functional outcome in FDPT zone I rupture repaired by palmaris longus (PL) tendon grafting augmented with human amniotic (hAM) and adipose derived mesenchymal stem cell (ASCs).

CASE PRESENTATION

We present a case of a 31-years old male sport climbing athlete with excruciating pain in the right middle finger due to an injury at distal phalangeal area occurred two months earlier. Intraoperatively, Bruner's incision was performed for exploration. A modified Kessler suture technique with running sutures around the sutured stump was used. We slightly overcorrected tension between PL and FDPT distal stumps. We shielded the distal and proximal sutured areas with hAM augmented with ASCs. The result was remarkable as he could return to competitive sport.

CLINICAL DISCUSSION

Zones I and II have a high adhesion risk due to their complex structures. In the case of the PL tendon graft, the sutured stump lies in these zones which can affect outcomes. An HAM augmented with ASCs has an anti-adhesive property that allows smooth gliding of the tendon FDPT on two sutured stump junctions, as well as stimulating the tendon to produce tenocytes, which accelerates tendon healing.

CONCLUSION

The combination of our technique and regenerative therapy effectively prevents adhesions and modulates tendon healing.

Use of Silicone Tubes as Antiadhesion Devices in a Modified Two-Stage Flexor Tendon Reconstruction in Zone II: A Retrospective Study

PURPOSE

This study aimed to assess the outcome of a modified two-stage flexor tendon reconstruction using silicone tubes as antiadhesion devices while performing simultaneous tendon grafting.

METHODS

From April 2008 to October 2019, 16 patients (21 fingers) with zone II flexor tendon injuries, who sustained failed tendon repair or neglected tendon laceration, were treated by a modified two-stage flexor tendon reconstruction. The first stage of treatment comprised flexor tendon reconstruction with interposition of silicone tubes to minimize fibrosis and adhesion around the tendon graft; the second stage of treatment comprised silicone tube removal under local anesthesia.

RESULTS

The patient median age was 38 (range, 22-65) years. After a median follow-up period of 14 (range, 12-84) months, the median total active motion (TAM) of fingers was 220° (range, 150-250°). Excellent and good TAM ratings were identified in 71.4%, 76.2%, and 76.2% according to the Strickland, modified Strickland, and American Society for Surgery of the Hand (ASSH) evaluation systems, respectively. At follow-up, complications included superficial infections in two fingers of one patient whose silicone tube was removed 4 weeks postoperatively. The most common complication was a flexion deformity of the proximal interphalangeal joint (four fingers) and/or distal interphalangeal joint (nine fingers). The rate of failed reconstruction was higher in patients with preoperative stiffness and infection.

CONCLUSIONS

Silicone tubes are suitable antiadhesion devices, and the modified two-stage flexor tendon reconstruction technique is an alternative procedure with a shorter rehabilitation period for complicated flexor tendon injury, compared with current popular reconstructions. Preoperative stiffness and postoperative infection may compromise the final clinical outcome.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Applications of functionally-adapted hydrogels in tendon repair

Despite all the efforts made in tissue engineering for tendon repair, the management of tendon injuries still poses a challenge, as current treatments are unable to restore the function of tendons following injuries. Hydrogels, due to their exceptional biocompatibility and plasticity, have been extensively applied and regarded as promising candidate biomaterials in tissue regeneration. Varieties of approaches have designed functionally-adapted hydrogels and combined hydrogels with other factors (e.g., bioactive molecules or drugs) or materials for the enhancement of tendon repair. This review first summarized the current state of knowledge on the mechanisms underlying the process of tendon healing. Afterward, we discussed novel strategies in fabricating hydrogels to overcome the issues frequently encountered during the applications in tendon repair, including poor mechanical properties and undesirable degradation. In addition, we comprehensively summarized the rational design of hydrogels for promoting stem-cell-based tendon tissue engineering via altering biophysical and biochemical factors. Finally, the role of macrophages in tendon repair and how they respond to immunomodulatory hydrogels were highlighted.

Risk factors associated with tendon adhesions after hand tendon repair

Background

Tendon adhesions after hand tendon repair are one of the most difficult complications of hand surgery and can cause severe disability. This study aimed to assess the risk factors associated with tendon adhesions after hand tendon repair to provide a theoretical foundation for the early prevention of tendon adhesions in patients with tendon injuries. Moreover, this study intends to increase doctors' awareness of the issue and serves as a reference for developing new prevention and treatment strategies.

Methods

We retrospectively analyzed 1,031 hand trauma cases that underwent repair after finger tendon injury in our department between June 2009 and June 2019. Tendon adhesions, tendon injury zones, and other relevant information were collected, summarized, and analyzed. The significance of data was determined using a t-test or Pearson's chi-square test, and odds ratios (OR) were calculated using logistic regression tests to describe factors associated with post-tendon repair adhesions.

Results

A total of 1,031 patients were enrolled in this study. There were 817 males and 214 females with an average age of 34.98 (2-82) years. The injured side included 530 left and 501 right hands. Postoperative finger tendon adhesions occurred in 118 cases (11.45%), including 98 males and 20 females, 57 left and 61 right hands. The risk factors for the total sample in the descending order were degloving injury, no functional exercise, zone II flexor tendon injury, time from injury to surgery >12 h, combined vascular injury, and multiple tendon injuries. The flexor tendon sample shared the same risk factors as the total sample. Risk factors for the extensor tendon sample were degloving injury, no functional exercise.

Conclusions

Clinicians should pay close attention to patients with tendon trauma in hand having the following risk factors: degloving injury, zone II flexor tendon injury, lack of functional exercise, time from injury to surgery >12 h, combined vascular injury, and multiple tendon injuries. Due to the high risk of post-repair adhesions in patients with the conditions mentioned above, individualized treatment measures should be designed for the risk factors, and postoperative functional exercise of the hand is required.

Functional outcomes of a modified Duran postoperative rehabilitation protocol after primary repairs of pediatric hand flexor tendon injuries

The objective of this study was to determine whether pediatric patients undergoing flexor tendon repair who underwent 4 weeks of immobilization followed by a modified Duran controlled passive motion rehabilitation protocol will have favorable outcomes. A study was performed at a tertiary pediatric hospital of patients <18 years who underwent primary flexor tendon repairs in zones 1-4. Outcomes were calculated by total active motion and classified by the original Strickland criteria or Buck-Gramcko criteria. Twenty-eight patients with 34 injured fingers were included. Mean age was 11.4 years (range 2.4-17.9) with 17 males (61%) and 11 females (39%). Thirty-five percent of injuries occurred in zone 1; 35% zone 2; 6% zone 3; and 24% zone 4. All underwent a modified Duran postoperative rehabilitation protocol following a period of immobilization. The majority of patients achieved favorable outcomes, with 86% of cases classified as good/excellent. Thirty (88%) cases received surgery acutely (within 3 weeks). Of these, 70% achieved excellent outcomes, 17% good, and 13% fair. Four (12%) chronic cases underwent primary repair (range 24-68 days), achieving excellent outcomes in 50%, good in 25%, and fair in 25%. Three (75%) patients with delayed primary repair exhibited stiffness, which was greater than the 17% of patients with acute repairs ( P = 0.03). Approximately 1 month of immobilization followed by a modified Duran rehabilitation protocol leads to favorable outcomes in children with flexor tendon repairs. Children with delayed surgery (>3 weeks) who underwent primary repair generally still achieved good outcomes but were more likely to have stiffness. Level of evidence: III.

Medium-term clinical outcomes of Zone 2B/2C finger flexor tendon repairs: influence of management of flexor digitorum superficialis

III.

Risk factors for reoperation after flexor tendon repair: a registry study

The aim of this study was to identify risk factors for reoperations after Zones 1 and 2 flexor tendon repairs. A multiple logistic regression model was used to identify risk factors from data collected via the Swedish national health care registry for hand surgery (HAKIR). The studied potential risk factors were age and gender, socio-economics and surgical techniques. Included were 1372 patients with injuries to 1585 fingers and follow-up of at least 12 months (median 37 IQR 27-56). Tendon ruptures occurred in 80 fingers and tenolysis was required in 76 fingers. Variables that affected the risk of rupture were age >25 years (p < 0.001), flexor pollicis longus tendon injuries (p < 0.001) and being male (p = 0.004). Injury to both finger flexors had an effect on both rupture (p = 0.005) and tenolysis (p < 0.001). Understanding the risk factors may provide important guidance both to surgeons and therapists when treating patients with flexor tendon injuries.Level of evidence: III.

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.

Traumatic Zone II Flexor Tendon Injury Repair Through a Traumatic Dorsal Approach

Zone II flexor tendons present unique challenges for repair because of their complex anatomy in a confined space. The approach for zone II injuries is often dictated by preexisting traumatic skin lacerations, with a midaxial or volar approach being most common. In some injuries, this approach is not viable, and alternative approaches must be considered. A 45-year-old man presented with a traumatic crush injury that caused complete disruption of the skin, tendon, capsule, collateral ligament, and volar plate and laceration of the flexor digitorum profundus in zone II near the proximal interphalangeal joint. Given the large, near-circumferential zone of injury, we used the traumatic dorsal wound for the flexor tendon for repair. There are no reports of this approach in the literature. Postoperatively, the proximal interphalangeal joint was immobilized for 6 weeks with a K-wire. The patient was followed in the clinic and prescribed occupational therapy. At the 4-month postoperative visit, the patient had a healed incision, no signs of infection, and intact median/radial sensations. Functional testing showed a loose composite fist, improved range of motion, and 2-cm tip-to-palm deficiency of the index finger. Grip strength was 85 lb in the right hand and 60 lb in the left hand. Although patients are not always expected to regain full function, their postoperative course may be further complicated by adhesion and the need for tenolysis. Given these historical complications of tendon repair and our patient's ability to return to work with satisfactory functional outcomes, this approach may be a viable option for treating this unique injury pattern. [Orthopedics. 2022;45(4):e216-e219.].

Teaching and Assessing Cognitive Competencies in Aesthetic and Plastic Surgery

BACKGROUND

Cognition, part of surgical competence, employs forward planning, error prevention, and orchestrating technical skills. Thus, an understanding of mental processes used by experts throughout patient care is essential to teaching such competencies. This study aims to analyze and compare mental models of two distinct procedures in plastic surgery, breast augmentation and flexor tendon repair, to develop a framework to define cognitive competencies in plastic surgery aided by a review of the literature.

METHODS

Based on data from a-priori cognitive task analyses, literary sources, and field observations of breast augmentation surgery and flexor tendon repair, task-lists were produced for each procedure. Two mental models were developed using fuzzy logic cognitive maps to visually illustrate and analyze cognitive processes employed in either procedure. A comparison of the models aided by literature was used to define the cognitive competencies employed, identify differences in the decision-making process, and provide a guiding framework for understanding cognitive competencies.

RESULTS

Five distinct cognitive competency domains were identified from the literature applicable to plastic surgery, namely situation awareness, decision-making, task management, leadership, and communication and teamwork. Differences in processes of decision-making employed between an elective and a trauma setting were identified. A framework to map cognitive competencies within a generic mental model in surgical care was synthesized and methods were suggested for training on such competencies.

CONCLUSION

Cognitive competencies in different settings in plastic surgery are introduced using a comparative study of two mental models of distinct procedures to guide the teaching and assessment of such competencies.

Initial Experience with the PONTiS Tendon Repair System in Traumatic Upper Extremity Injuries

BACKGROUND

Tendon injuries of the upper extremity remain a common surgical condition requiring prompt intervention. We review our initial experience with the PONTiS flexor tendon repair system (PFRS) - a knotless, multifilament stainless steel crimp system.

METHODS

Consecutive patients undergoing repair by our plastic and orthopedic surgeons with the PFRS were reviewed from 2015-2017. Multivariate risk and Kaplan-Meier survival analyses were performed to assess risk factors associated with complications.

RESULTS

Eighty-one patients with mean follow up of 75 days (range 0 - 33 months) were identified. The most common demographics of our patients were right-handed (82.9%), male (71.4%), laborer (35.7%), sustaining laceration injuries (77.1%) at zone 2 (27.2%). There was an average of 3.7 tendon injuries per patient. Associated injuries included fractures (21.4%), arterial injuries (24.3%), and nerve injuries (61.4%). Thirteen (16.0%) patients developed complications: adhesions/contracture (4), rupture (2), flap ischemia (2), arterial thrombosis (1), wound dehiscence (1), tendon lag (1), and erosion of the PFRS through soft-tissue grafts (2). Multivariate analysis identified poor soft-tissue coverage (OR 9.990; p=0.043) and zone 2 involvement (OR 7.936; p=0.016) as risk factors, while epitendinous repairs (OR 0.096; p=0.010) were protective against complications.

CONCLUSIONS

The PFRS system is rapid and simple to deploy and advantageous especially in multiple traumatic tendon injuries. Compared to traditional suture repair, it has a comparable overall complication profile but superior rupture and tenolysis rates. We advise use with caution in cases with poor soft tissue coverage to minimize risks of extrusion and strongly recommend the use of epitendinous sutures concurrently to limit complications.

Dynamic Tendon Grip (DTG™) novel knot array compared to traditional sutures for zone two flexor tendon injury - a biomechanical feasibility study

BACKGROUND

Flexor tendon injuries pose many challenges for the treating surgeon, the principal of which is creating a strong enough repair to allow early active motion, preserving a low-profile of the repair to prevent buckling and subsequent pulley venting. A main concern is that a low-profile repair is prone to gap formation and repair failure. The Dynamic Tendon Grip (DTG™) all suture staple device claims to allow a strong and low-profile repair of the flexor tendon. The purpose of this study is to test the effects of the DTG™ device in early active motion simulation on range of motion, load to failure and gap formation and to compare it to traditional suturing technique.

METHODS

Twelve fresh-frozen cadaveric fingers were assigned to two groups: DTG™ device (n = 9) and traditional suturing (double Kessler 4-core suture and a peripheral suture, n = 3). The deep flexor was incised and repaired in zone 2, and active motion simulation was carried out with a cyclic flexion-extension machine. Finger range of motion and gap formation were measured, as well as load to failure and method of repair failure.

RESULTS

Following motion simulation, ROM decreased from 244.0 ± 9.9° to 234.5 ± 5.8° for the DTG™ device compared to 234.67 ± 6.51° to 211.67 ± 10.50° for traditional suturing. The DTG™ repair demonstrated gap formation of 0.93 ± 0.18 mm in 3 of 8 specimens after applying 1 kg load, which negated after load removal. Load to failure averaged 76.51 ± 23.15 N for DTG™ and 66.31 ± 40.22 N for the traditional repair. Repair failure occurred as the suture material broke for the DTG™ array and at the knot level for the traditional repair.

CONCLUSIONS

The DTG™ all-suture stapling concept achieved a strong low-profile repair in zone 2 flexor tendon injury after active motion simulation. Further clinical studies will be needed to determine the effectiveness of this device compared to traditional techniques.

Outcomes at 3 Months of a Place and Active Hold Method of Flexor Tendon Rehabilitation Following Zone II Injury

Background: Previous studies have shown that outcomes following a place and active hold (PAH) are better than a passive flexion protocol after a two-strand core-suture repair of flexor tendons injuries in zone II. This study aims to determine the outcomes of a PAH protocol of flexor tendon rehabilitation following a four-strand core-suture plus an epitendinous suture repair of the flexor digitorum profundus (FDP) combined with a simple horizontal loop repair of the flexor digitorum superficialis (FDS). Methods: This is a prospective study of patients with complete injury to both flexor tendons in zone II. All tendons were repaired with a simple horizontal loop for FDS and four-strand core-suture plus epitendinous suture for FDP. The PAH protocol was used postoperatively for 6 weeks. The outcome was evaluated using flexion contracture and total active motion (TAM), interpreted using Strickland criteria and categorised as excellent, good, fair and poor at 6 weeks and 3 months. The linear regression model was used to determine predictors of outcomes. Results: The study included 32 patients with flexor tendon injury in 46 fingers. No repairs ruptured, and 24 (52%) digits achieved good or excellent motion 6 weeks after surgery using the Strickland criteria. According to the Strickland criteria, 41 (89%) digits ranked as excellent and good with no poor result at a 3-month follow-up. Four patients had 5-10° of flexion contracture. Age was the predictor of TAM at 6 weeks and accounted for 13% of its variation. Improvement of TAM from 6 weeks to 3 months was related to age and flexion contracture at 6 weeks. Conclusions: The PAH protocol can be considered a safe technique for flexor rehabilitation after four-strand core-suture repair of FDP in zone II. Level of Evidence: Level IV (Therapeutic).