New Developments Are Improving Flexor Tendon Repair

Effects of A2 Pulley Venting on Bowstringing and Tendon Slack: A Biomechanical Investigation

BACKGROUND

A2 pulley release is often needed for exposure of the lacerated tendon, retrieval of retracted tendons, placement of core sutures, or to permit full motion and gliding of the repaired and edematous tendon. However, there is no agreement in the literature on the specific quantity of pulley venting that can be performed and recommendations are limited to an undefined "judicious release" of the pulleys when necessary.

METHODS

Following a previously developed testing protocols, finger kinematics, tendon excursion, and bowstringing were evaluated on cadaveric hands for venting in increments of 20% of the pulley length.

RESULTS

In our study, we found a statistically significant influence of venting on bowstringing, although no difference was found between fingers, and a significant difference in tendon slack, which was variable depending on the finger. Bowstringing started increasing at 20% of A2 venting and peaked at full release. Tendon slack did not start until 40% of A2 venting on the index finger, but started at 20% on the middle, ring, and small fingers.

CONCLUSIONS

Venting of the A2 pulley leads to an incremental increase in tendon bowstringing and tendon slack. However, differences in metacarpophalangeal flexion angle were not observed until full A2 pulley release, and only observed in the index finger, and no differences were observed in proximal interphalangeal flexion angles. Therefore, the benefit of releasing the A2 pulley when clinically necessary will likely outweigh the risks of loss of motion or strength.

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.

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.

Outcomes of 218 primary single-finger flexor tendon repairs up to 1 year after surgery: a multicentre cohort study

In this retrospective multicentre cohort study, we present the results of primary single-finger flexor tendon repairs in zones 1 to 3 between 2014 and 2021. Data from 218 patients were retrieved with their demographics, injury and surgery characteristics and therapy outcomes. The data were systematically collected and analysed at predefined time points up to 1 year after surgery. A good to excellent return of motion was achieved by 77% (Tang classification) and 92% (American Association for Surgery of the Hand classification) of patients at 1 year. The tendon rupture rate was 8.7%. Time had a significant impact on the recovery of finger motion and grip strength of up to 1 year, of patient satisfaction and upper extremity function up to 26 weeks, and of pain up to 13 weeks after surgery. Our results demonstrate that it is worthwhile to assess therapy outcomes over various measurement periods, as some outcomes may continue to improve up to 1 year after flexor tendon repair surgery.Level of evidence: III.

Safety and efficacy of ultrasonography of tension after zone II flexor tendon repair: A randomized controlled trial

BACKGROUND

Primary flexor tendon repairs of lacerations in zone II of the hand are fraught with problems. Traditionally, exercise (active and passive), orthoses, and physical agents are common interventions for the rehabilitation of patients experiencing these issues. One area of focus in this field is how to safely utilize tension to lengthen gliding distance following zone II injury. Finding effective solutions in this area is a key priority for improving patient outcomes and quality of life.

PURPOSE

To identify the optimal immobilization position that meets safety standards for tension and is the most efficient, and consequently, to validate our clinical effectiveness.

STUDY DESIGN

A cross-sectional study was adopted for the first part of the research (Research 1). A prospective, parallel, 2-group, randomized trial was conducted with concealed allocation and single blinding in the second part of the research (Research 2).

METHODS

A total of 60 healthy adults were recruited to select the best-fit protective immobilization position in Research 1, which was confirmed by tendon tension (via Young's modulus) and excursion (via gliding distance). We then randomly assigned 45 patients after zone II flexor tendon repair into two groups in Research 2 to compare functional outcomes. The control group underwent the conventional modified Duran protocol with early passive motion, while the experimental group received the protocol (optimized by Research 1) with early active motion. Ultrasonography was used to measure the tension and excursion of the flexor tendons. The outcomes measured at 16 weeks post-repair included total active motion, strength, the Disabilities of the Arm, Shoulder and Hand, and Strickland scores.

RESULTS

Three participants were unable to participate in Research 2 due to medical issues and poor attendance. The investigation found that the safe tendon threshold was 345.09 ± 87.74 kPa for partial active digital motion among the 60 participants. The optimal immobilization position requires the wrist to be neutral with a flexion angle of 30° at the metacarpophalangeal joint. The grip strengths (p = 0.012), ratio of grip strength (p = 0.015), the Disabilities of the Arm, Shoulder and Hand (p = 0.036), and total active motion (p = 0.023) differed significantly between the two groups.

CONCLUSIONS

Protective immobilization of the wrist in a neutral flexion position and with the metacarpophalangeal joint flexed at 30° can secure the repaired flexor tendon safely and efficiently. The effects of an early active motion ‎protocol may improve the grip strength and upper limb mobility of individuals after zone II flexor tendon repair.

CLINICAL TRIAL REGISTRATION

ChiCTR2000030592.

Drug Delivery Approaches to Improve Tendon Healing

Tendon injuries disrupt the transmission of forces from muscle to bone, leading to chronic pain, disability, and a large socioeconomic burden. Tendon injuries are prevalent; there are over 300,000 tendon repair procedures a year in the United States to address acute trauma or chronic tendinopathy. Successful restoration of function after tendon injury remains challenging clinically. Despite improvements in surgical and physical therapy techniques, the high complication rate of tendon repair procedures motivates the use of therapeutic interventions to augment healing. While many biological and tissue engineering approaches have attempted to promote scarless tendon healing, there is currently no standard clinical treatment to improve tendon healing. Moreover, the limited efficacy of systemic delivery of several promising therapeutic candidates highlights the need for tendon-specific drug delivery approaches to facilitate translation. This review article will synthesize the current state-of-the-art methods that have been used for tendon-targeted delivery through both systemic and local treatments, highlight emerging technologies used for tissue-specific drug delivery in other tissue systems, and outline future challenges and opportunities to enhance tendon healing through targeted drug delivery.

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.

Identifying Palmar Skin Surface Landmark for Locating A2 Pulley during Cadaveric Dissection of the Hand

The A2 and A4 pulleys are fibro-osseous structures that support the flexor tendon function. Injury to these pulleys can result in bowstringing and limited tendon excursion. Thus, having an understanding of the skin surface landmark of the A2 pulley is crucial to safeguard it during hand surgery.

Methods

We performed cadaveric dissection of 62 hands. For 248 fingers, the measurement of distance A, which is half the distance between the palmar digital crease and proximal interphalangeal crease reflected in the palm, and distance B, which is the distance between the A2 pulley's starting point and the palmar digital crease, were taken by a caliber. Statistical analysis was performed using the paired sample t test to determine whether there was a significant difference between distances A and B.

Results

Our study revealed that there was no significant difference (p>0.05) between the measured starting point of the A2 pulley and its proposed surface landmark for the index, middle, and small fingers. Conversely, the ring finger showed a statistically significant difference of 1 mm more proximal.

Conclusions

By measuring the distance between the palmar digital crease and proximal interphalangeal crease and reflecting it proximally in the palms, one can anticipate the location of the A2 pulley's starting point for each digit, except for the ring finger. The ring finger's starting point is 1 mm more proximal than the other digits. Knowing the starting point of the A2 pulley will help hand surgeons limit incisions and avoid accidental injury during hand surgery.

Tips to Successful Flexor Tendon Repair and Reconstruction with WALANT

WALANT has generated many changes that have improved flexor tendon repair and reconstruction in the last 10 years. Seeing awake unsedated educable patients move repaired reconstructed tendons during the surgery has changed how we do surgery and therapy in many ways for the better. This article offers many tips on how to get better results in using these new techniques with the help of WALANT.

Flexor Tendon Repair Techniques: M-Tang Repair

The authors present the methods and outcomes from six institutes where M-Tang repairs with early active flexion exercise are used for zone 2 digital flexor tendon repair. The authors had close to zero repair ruptures, and few digits needed tenolysis. The excellent to good results are generally between 80% and 90%. In the pandemic period, less stringent therapy supervision might have allowed some patients to move too aggressively, with repair ruptures not seen before the pandemic in one institute. In Nantong, Yixing, and Saint John, the rupture incidence is zero to 1%. In Florence and Heidelberg, the rupture incidence was 3%.

How controlled motion alters the biophysical properties of musculoskeletal tissue architecture

INTRODUCTION

Movement is fundamental to the normal behaviour of the hand, not only for day-to-day activity, but also for fundamental processes like development, tissue homeostasis and repair. Controlled motion is a concept that hand therapists apply to their patients daily for functional gains, yet the scientific understanding of how this works is poorly understood.

PURPOSE OF THE ARTICLE

To review the biology of the tissues in the hand that respond to movement and provide a basic science understanding of how it can be manipulated to facilitate better functionThe review outlines the concept of controlled motion and actions across the scales of tissue architecture, highlighting the the role of movement forces in tissue development, homeostasis and repair. The biophysical behaviour of mechanosensitve tissues of the hand such as skin, tendon, bone and cartilage are discussed.

CONCLUSION

Controlled motion during early healing is a form of controlled stress and can be harnessed to generate appropriate reparative tissues. Understanding the temporal and spatial biology of tissue repair allows therapists to tailor therapies that allow optimal recovery based around progressive biophysical stimuli by movement.

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.

The Effect of Flexor Digitorum Profundus Repair Position Relative to Camper Chiasm on Tendon Biomechanics

PURPOSE

The purpose of this study was to investigate the impact of repairing a zone II flexor digitorum profundus (FDP) laceration anatomically versus extra-anatomically on tendon loads and work of flexion (WOF).

METHODS

Twenty digits from 5 cadaveric specimens were tested using an in vitro active finger motion simulator under 2 FDP tendon repair conditions: anatomic and extra-anatomic. Tensile loads in FDP and flexor digitorum superficialis (FDS), WOF, and total active finger range of motion (ROM) were measured using in-line load cells and electromagnetic tracking, respectively.

RESULTS

The anatomic repairs had no effect on tendon loads or WOF for either FDP or FDS. The extra-anatomic repairs increased FDP loads by 32% and decreased FDS loads by 9% compared with those in the intact condition. This pattern was similar for WOF following extra-anatomic repairs, which increased FDP WOF by 31% and decreased FDS WOF by 18%. Comparing the 2 repairs, FDP loads and WOF were 25% and 22% greater, respectively, with extra-anatomic repairs compared with anatomic repairs, with no significant change in FDS. Total active ROM was not affected by either repair.

CONCLUSIONS

In this in vitro cadaveric model, extra-anatomic repairs of FDP increased tendon loads and WOF compared with anatomic repairs.

CLINICAL RELEVANCE

On the basis of this study, reconstitution of the anatomic relationship of FDP and FDS at the Camper chiasm during the repair of zone II flexor tendon lacerations is recommended.

The Effects of the TSOL Knot on the Repair Strength and Gliding Resistance Following Flexor Tendon Repair

BACKGROUND

The stability of a suture knot construct has been realized as an important parameter that affects the strength of flexor tendon repairs. A novel 2-strand-overhand-locking (TSOL) knot, which is not commonly used in the clinical setting, recently was reported to increase repair strength and to decrease tendon gliding resistance in a 2-strand repair technique. The purpose of the present study was to investigate the effect of the TSOL knot on tendon repair strength and gliding resistance compared with a typical surgical knot in both 2-strand and 4-strand repair techniques using an in vitro turkey flexor tendon model.

METHODS

Sixty flexor digitorum profundus tendons from the long digit of the turkey foot were divided evenly into 4 groups and repaired with the following techniques: (1) a 2-strand modified Pennington repair with a square knot, (2) a 2-strand modified Pennington repair with a TSOL knot, (3) a 4-strand grasping cruciate repair with a square knot, and (4) a 4-strand grasping cruciate repair with a TSOL knot. Repaired tendons were tested for failure mode, gliding resistance, and repair strength at failure.

RESULTS

The repair strength and stiffness of the 4-strand repairs were significantly higher than those of the 2-strand repairs, regardless of knot type (p < 0.05). The repair strength at failure of the TSOL knot was significantly greater than that of the square knot in 2-strand repairs (p < 0.05) but not in 4-strand repairs. The gliding resistance of the TSOL knot was significantly decreased compared with that of the square knot in both 2-strand and 4-stand repairs (p < 0.05). With regard to failure mode, the TSOL knot was less likely to fail due to knot unravelling.

CONCLUSIONS

In this in vitro biomechanical study involving the use of turkey flexor tendons to compare gliding resistance and repair strength characteristics for knot-inside 2 and 4-strand repairs, the TSOL knot was associated with decreased repaired tendon gliding resistance, regardless of the number of strands used. Although the TSOL knot also increased the repair strength, the difference was only significant when 2-strand repairs were used. The results of our study support the use of the TSOL knot in the clinical setting of flexor tendon repair using 2 or 4-strand, knot-inside methods.

CLINICAL RELEVANCE

In surgical repair of flexor tendons, there is substantial interest in maximizing strength while minimizing friction. This study shows the potential utility of the TSOL knot to increase repair strength while decreasing gliding resistance, particularly in 2-strand repairs.

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.

A Review of Outcome Reporting Practices after Flexor Tendon Repair in Zones 1 and 2

Background: Outcome reporting following flexor tendon repair has historically concentrated on range of movement. Recently, there has been an increase in the use of patient-reported outcome measures (PROMs). At present, there is no agreed set of outcomes to report following flexor tendon repair. The aim of this study is to review outcome reporting practices after flexor tendon repair in zones 1 and 2. Methods: A search of Ovid MEDLINE, Ovid EMBASE and Cumulative Index to Nursing and Allied Health Literature (CINAHL) between 1 January 1980 and 31 December 2019 was performed to identify the studies that reported outcomes following the repair of flexor tendons in zones 1 and 2. Study characteristics and data with regard to the reporting of eight outcome domains was extracted: functional outcome (quantitative), functional outcome (subjective), activities of daily living (ADL), satisfaction/quality of life, post-treatment recovery, resources, aesthetics and safety. Results: A total of 94 out of 4,118 articles identified were included in the review. All studies reported range of motion using 17 different methods of measurement. Eleven studies defined measurement methods incorrectly or unclearly. Only 16 studies reported PROMs, with only one reporting data on assessment of quality of life. Eighteen studies reported time away from employment. Minimal data on resource utilisation and aesthetics were included. Conclusion: This review highlights wide heterogeneity and paucity of data reporting clinical outcomes of flexor tendon surgery. The development of a core outcome set that would ensure essential outcomes are correctly defined, measured and reported is required. Level of Evidence: Level IV (Prognostic).

Outcomes of Wide-Awake Flexor Tendon Repairs in 58 Fingers and 9 Thumbs

PURPOSE

The purpose of this study was to present the outcomes of wide-awake flexor tendon repairs in zones 1 and 2 in a major hand trauma referral center.

METHODS

Zone 1 and zone 2 wide-awake flexor tendon repairs performed between August 2018 and March 2020 were analyzed retrospectively. Outcomes were assessed by the original Strickland-Glogovac criteria for fingers and Buck-Gramcko scoring system for thumbs. Further descriptive analysis of the groups according to potential negative factors, such as injury mechanism, concomitant neurovascular injury, and the extent of injury in zone 2, were performed.

RESULTS

A total of 94 tendons were repaired in 67 digits (58 fingers, 9 thumbs) of the 61 patients included in the study. Satisfactory results were achieved in 89.6% of the fingers and 77.8% of the thumbs. Intraoperative gapping was corrected after active digital extension-flexion test in 1 patient. Rupture was seen in 1 patient for a rate of 1.5%. The tenolysis indication rate was 5.1% for fingers and 11.1% for thumbs.

CONCLUSIONS

In our series, functional outcome scores, tenolysis, and rupture rates remained similar with findings in the literature. The outcome of a flexor tendon repair is influenced by many factors that cannot be controlled intraoperatively. To assess the effect of performing the repair in a wide-awake setting on the outcome, clinical trials with large patient groups are needed.

LEVEL OF EVIDENCE

Therapeutic IV.

Secondary Procedures following Flexor Tendon Reconstruction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the indications and management options for secondary flexor tendon reconstruction, including tenolysis, tendon grafting, and tendon transfers. 2. Understand the reconstructive options for pulley reconstruction. 3. Understand the options for management of isolated flexor digitorum profundus injuries.

SUMMARY

Despite current advances in flexor tendon repair, complications can still occur following surgery. This article presents the spectrum of treatment options for secondary flexor tendon reconstruction ranging from tenolysis to one- and two-stage tendon grafting, and tendon transfers. In addition, an overview of pulley reconstruction and the treatment of isolated flexor digitorum profundus injuries are discussed. A management algorithm for secondary flexor tendon reconstruction is provided.

Flexor tendon repair: recent changes and current methods

The current clinical methods of flexor tendon repair are remarkably different from those used 20 years ago. This article starts with a review of the current methods, followed by presentation of past experience and current status of six eminent hand surgery units from four continents/regions. Many units are using, or are moving toward using, the recent strong (multi-strand) core suture method together with a simpler peripheral suture. Venting of the critical pulleys over less than 2 cm length is safe and favours functional recovery. These repair and recent motion protocols lead to remarkably more reliable repairs, with over 80% good or excellent outcomes achieved rather consistently after Zone 2 repair along with infrequent need of tenolysis. Despite slight variations in repair methods, they all consider general principles and should be followed. Outcomes of Zone 2 repairs are not dissimilar to those in other zones with very low to zero incidence of rupture.

An Analysis of the Clinical Efficacy of Early Dynamic Orthosis after Finger Extensor Digitorum Rupture

OBJECTIVE

The main objective is to compare the clinical efficacy of the early use of dynamic orthosis in patients with a finger extensor digitorum rupture.

METHODS

A total of 50 patients with hand and foot trauma who received surgical treatment in our hospital from March 2017 to February 2021 were selected, and two patients were excluded from the study. The patients were randomly divided into two groups. The control group (group A) was treated with plaster fixation and routine rehabilitation, and the study group (group B) underwent dynamic low-temperature thermoplastic plate fixation and routine rehabilitation. Total active motion (TAM) and total passive motion (TPM) of the injured finger before treatment, one month after treatment, two months after treatment, and after corrective treatment were compared.

RESULTS

After treatment following a finger extensor digitorum rupture, the TAM and TPM of the injured fingers increased significantly in both groups. The TAM and TPM in group B were significantly better than those in group A after one and two months of treatment (P < 0.05). After two months of treatment, the rates of improvement in TAM and TPM in group B were significantly higher than those in group A.

CONCLUSION

The early use of dynamic orthosis can significantly improve the motor function and motion amplitude of the injured finger, increase the elasticity and extension of the finger extensor digitorum, and promote the recovery of muscle strength. It is an effective corrective method for tendon contracture after finger extensor digitorum rupture and has great value in clinical application.

Important updates of finger fractures, entrapment neuropathies and wide-awake surgery of the upper extremity

Hand surgery is rapidly changing. The wide-awake approach, minimum dissection surgery and early protected movement have changed many things. This is an update of some of the important changes regarding early protected movement with K-wired finger fracture management, simplification of nerve decompression surgery, such as elbow median and ulnar nerve releases, and some new areas in performing surgery with wide-awake local anaesthesia without tourniquet.

The impact of transverse components on 4-strand tendon repairs

We investigated the effects of the transverse components of a tendon core suture on tensile resistance and strength of 4-strand repairs. Forty-four pig flexor tendons were repaired with one of the following four methods: double Tsuge, U-shaped, 4-strand cross and 4-strand rectangular repairs. We recorded the number of the repaired tendons that formed a 2 mm gap between the tendon ends during cyclic loading for 20 cycles, stiffness of the tendon at the 1st and 20th cycle, gap distance at the repair site and ultimate strength of the repair at the 20th cycle. When transverse components were added to the core suture, a greater number of tendons formed a 2 mm gap during cyclic loading. The stiffness gradually decreased, and the repair site's gap distance after cyclic loading increased with the presence of transverse components of the sutures. We conclude that the core suture's transverse components negatively impact the tensile resistance of 4-strand tendon repairs.

Rehabilitation after flexor tendon repair and others: a safe and efficient protocol

In this review I detail the protocol that I use after flexor tendon repair and outline my experience regarding how its framework might be used for other disorders. The early passive-active flexion protocol has a sufficient number of cycles of active flexion in each exercise session, which is at least 40, and ideally 60 to 80. The frequency of exercise sessions may range from 4 to 6 a day, distributed in the morning, afternoon and evening. Increasing the number of daily sessions without a sufficient number of runs in each session is ineffective. In the first 2-3 weeks after surgery, active digital flexion should go through only a partial range. In weeks 4-6, the patient gradually moves through the full range. With modifications, I suggest generalization of the partial-range finger motion to therapy after treating other hand injuries. I consider partial-range active flexion a generalizable working principle for different hand disorders.

The impact of transverse components on resistance and ultimate strength of 6-strand tendon repairs

We assessed the effects of tendon core sutures' transverse components on the tensile resistance of two commonly used 6-strand tendon repairs. Tang and Yoshizu #1 repairs (6-strand) were tested and compared with 4-strand rectangular and double Kessler sutures (4-strand). A total of 40 pig flexor tendons were tested under cyclic loading. We recorded the number of tendons that formed a 2-mm gap between two tendon ends during 20 cycles of cyclic loading test, stiffness at the 1st and 20th loading cycle, and gap distance at the repair site and the ultimate repair strength at the 20th cycles. We found that the Yoshizu #1 repairs were more prone to form gaps and their ultimate strength was significantly lower than that of the Tang repair. The transverse components in a 6-strand repair affect gap formation and failure strength.

Is releasing pulleys during flexor tendon repair "part and parcel"? Narrative review of the current evidence

BACKGROUND

The complex hand flexors pulleys system is essential in achieving efficient flexor tendons' function. Previous cadaveric studies demonstrated that A2 and A4 are the crucial pulleys in maintaining normal digits biomechanics. Realistically, the preservation of A2 and A4 pulleys during repairing flexor tendon laceration in zones one and two can be extremely challenging. We review the current published evidence in this article to answer the question of whether releasing the pulleys cause bowstringing or affects clinical outcomes.

METHODS

Literature search of the available databases.

RESULTS

There was no published comparative evidence. Retrospective case series have reported that no clinical bowstringing was noted after releasing flexor pulleys during flexor tendon repairs. Outcomes have been reported according to Tang and or Strickland criteria to assess range of motion (ROM). No functional hand scores or patients' satisfactions scores have been reported.

CONCLUSION

Releasing flexor pulleys during tendon repair to allow access or prevent impingement of the repaired tendon does not seem to cause bowstringing or affect outcome based on the limited available evidence. Future research is needed.

LEVEL OF EVIDENCE

Level 4.

Up to five-week delay in primary repair of Zone 2 flexor tendon injuries: outcomes and complications

We report the outcomes of delayed primary repair of flexor tendons in Zone 2 in 31 fingers and thumb (28 patients) averaging 15 days (range 4-37) after injury in 2020. The delay was longer than usual due to the COVID-19 pandemic. The tendons were repaired with a 6-strand core suture (M-Tang method) or a double Tsuge suture and a peripheral suture. This was followed by an early, partial-range, active flexion exercise programme. Adhesions in four digits required tenolysis. These patients were not with longest delay. Outcomes of two improved after tenolysis. The other two patients declined further surgery. One finger flexor tendon ruptured in early active motion. This was re-repaired, and final outcome was good. Overall excellent and good results using the Tang criteria were in 27 out of 31 fingers and thumbs (87%). The time elapsed between the injury and surgery is not an important risk factor for a good outcome, rather it depends on proper surgical methods, the surgeon's experience and early mobilization, properly applied. Adhesions may occur, but they can be managed with tenolysis.Level of evidence: IV.

Polytetrafluoroethylene (PTFE) suture vs fiberwire and polypropylene in flexor tendon repair

BACKGROUND

In this study, we evaluate the value of novel suture material based on monofilamentous-extruded polyfluoroethylene (PTFE) compared to polypropylene (PPL) and Fiberwire (FW).

MATERIALS AND METHODS

60 flexor tendons were harvested from fresh cadaveric upper extremities. 4-0 sutures strands were used in the PPL, FW and PTFE group. Knotting properties and mechanical characteristics of the suture materials were evaluated. A 4-strand locked cruciate (Adelaide) or a 6-strand (M-Tang) suture technique was applied as core sutures for a tendon repair. Two-way ANOVA tests were performed with the Bonferroni correction.

RESULTS

Stable knotting was achieved with 5 throws with the PPL material, 7 throws for FW and 9 throws for PTFE. In the PPL group, linear tensile strength was 45.92 ± 12.53 N, in the FW group 80.11 ± 18.34 N and in the PTFE group 76.16 ± 29.10 N. FW and PTFE are significantly stronger than PPL but show no significant difference among each other. Similar results were obtained in the subgroup comparisons for different repair techniques. The Adelaide and the M-Tang knotting technique showed no significant difference.

CONCLUSION

Fiberwire showed superior handling and knotting properties in comparison to PTFE. However, PTFE allows easier approximation of the stumps. In both, M-Tang and Adelaide repairs, PTFE was equal to FW in terms of repair strength. Both PTFE and FW provide for a robust tendon repair so that early active motion regimens for rehabilitation can be applied.

Early active mobilization after primary repair of the flexor pollicis longus tendon

BACKGROUND

There have been few studies regarding primary flexor tendon repair of the thumb following early active mobilization, whereas there have been multiple such studies of the finger. This study examined the outcomes of patients who underwent early active mobilization after primary repair of the flexor pollicis longus tendon.

METHODS

This study was a retrospective case series. Between 1993 and 2019, 17 thumbs of 17 consecutive patients with complete flexor pollicis longus tendon lacerations were treated using the Yoshizu #1 technique, followed by early active mobilization. The mean time between injury and primary flexor tendon repair was 2 days. Two thumbs had zone T1 injuries and 15 had zone T2 injuries. Mobilization of the thumb began on the first postoperative day with a combination of active extension and passive and active flexion. The mean follow-up period was 8 months. The percentage of total active motion of the thumb was regarded as the sum of the active motion of the two joints, divided by 140°. Functional outcomes were graded in accordance with the Strickland criteria.

RESULTS

Three repair ruptures occurred in thumbs treated by inexperienced surgeons. Excluding tendon ruptures, the mean percentage of total active motion of the thumb was 83%. The mean active flexion of the interphalangeal and metacarpophalangeal joints was 62° and 64°. The mean extension deficit was 8.8° at the interphalangeal joint and 7.5° at the metacarpophalangeal joint. According to Strickland's criteria, repairs to eight thumbs were ranked excellent, three were good, one was fair, and five were poor.

CONCLUSIONS

Our results are not inferior to the findings of previous reports regarding early postoperative mobilization after primary flexor pollicis longus tendon repair, in terms of the acquisition of active thumb motion. Poor outcomes result from repair rupture and increased extension deficits of the interphalangeal and metacarpophalangeal joints.

Printing a static progressive orthosis for hand rehabilitation

BACKGROUND

Static progressive orthosis is used for the treatment of severe joint contracture after trauma and/or surgery. However, a custom-fabricated static progressive splint would be expensive and labor intensive. Especially, owing to very limited payment under the current Taiwanese National Health Insurance, the incentives to fabricate a patient-specific splint are insufficient for a therapist. To ease splint construction, we introduced three-dimensional (3D)-printed "shark fin"-shaped device works as a static progressive orthosis for the hand rehabilitation. The aim of this study was to describe and demonstrate the newly designed device.

METHODS

This study included a 46-year male suffered from a left distal radius fracture and underwent open reduction internal fixation and a 23-year male with the right thumb flexor pollicis longus rupture, requiring tendon repair. Both subjects used this "shark fin"-shaped device to stretch for increasing range of motion (ROM) of wrist extension and the thumb.

RESULTS

The patient receiving ulnar shortening surgery used this device to stretch for increasing ROM of wrist extension. The active ROM of wrist extension improved from 30° to 50°. The other patient with the right thumb flexor pollicis longus rupture suffered from thumb contracture; the ROMs of the metacarpophalangeal (MCP) joint and interphalangeal (IP) joint were 40°-55° and 20°-25°, respectively. After tenolysis surgery, his ROMs of the MCP and IP joints were improved to 10°-35° and 40°-65°, respectively. Following physical therapy by applying the device, his ROMs of the MCP and IP joints were further increased to 0°-40° and 25°-70°, respectively.

CONCLUSION

Incorporating the "shark fin"-shaped orthosis into hand rehabilitation increased the ROM of wrist extension for a patient with distal radius fracture and improved the ROM of the MCP and IP joints in another patient after tenolysis surgery.

Use of Thermoplastic Rings Following Venting of Flexor Tendon Pulleys: A Biomechanical Analysis

PURPOSE

Normal digital flexion relies on flexor tendon pulleys to convert linear muscular force to angular digital motion. However, there is a growing trend to vent them partially during flexor tendon repair. The objective of this study was to examine the effects of a thermoplastic ring, acting as an external pulley, on flexor tendon biomechanics and finger range of motion (ROM) after pulley venting.

METHODS

We tested 15 cadaveric digits using an in vitro active finger motion simulator. We measured loads induced by flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) as well as joint ROM with sequential sectioning of the A2, A3, and A4 pulleys compared with an intact pulley condition. At each stage, external thermoplastic pulley rings were applied snugly over the proximal and middle phalanges to recreate A2 and A4 function, respectively.

RESULTS

After complete venting of the A2, A3, and A4 pulleys, proximal interphalangeal joint ROM significantly decreased by 13.4° ± 2.7° and distal interphalangeal joint ROM decreased by 15.8° ± 2.1°. Application of external rings over the proximal and middle phalanx resulted in a residual ROM decrease of 8.3° ± 1.9° at the proximal interphalangeal joint and 7.9° ± 2.1° at the distal interphalangeal joint, nearly restoring ROM. Similarly, complete pulley venting resulted in reduced FDS load by 37% and FDP load by 50% compared with intact pulleys. After application of external rings, loads were restored almost to normal, with a 9% reduction for FDS load and 9% reduction for FDP load compared with intact pulleys.

CONCLUSIONS

The application of thermoplastic rings acting as external pulleys is an effective, noninvasive, and reproducible approach to restore flexor tendon biomechanics and digit ROM after pulley venting.

CLINICAL RELEVANCE

Thermoplastic rings may be a useful therapeutic adjunct in restoring joint ROM and flexor tendon loads after surgical venting of the pulleys.

Hyaluronic Acid Treatment Improves Healing of the Tenorrhaphy Site by Suppressing Adhesions through Extracellular Matrix Remodeling in a Rat Model

Due to the limited supply of vessels and nerves, acute or chronic tendon injuries often result in significant and persistent complications, such as pain and sprains, as well as the loss of joint functions. Among these complications, tendon adhesions within the surrounding soft tissue have been shown to significantly impair the range of motion. In this study, to elucidate the effects of a hyaluronic acid (HA) injection at the site of tenorrhaphy on tendon adhesion formation, we used a full transection model of a rat’s Achilles tendon to investigate the anti-adhesive function of HA. Our initial findings showed that significantly lower adhesion scores were observed in the HA-treated experimental group than in the normal saline-treated control group, as determined by macroscopic and histological evaluations. Hematoxylin and eosin, as well as picrosirius red staining, showed denser and irregular collagen fibers, with the larger number of infiltrating inflammatory cells in the control group indicating severe adhesion formation. Furthermore, we observed that the expression of tendon adhesion markers in operated tendon tissue, such as collagen type I, transforming growth factor-β1, and plasminogen activator inhibitor-1, was suppressed at both the gene and protein levels following HA treatment. These results suggest that HA injections could reduce tendon adhesion formation by significantly ameliorating inflammatory-associated reactions.

Getting Better Results in Flexor Tendon Surgery and Therapy

Recently, better outcomes have been reported when up-to-date developments in flexor tendon surgery and therapy were followed. Slightly tensioned multistrand repairs, judicious venting of pulleys, and early active motion are widely accepted principles. In addition to these principles, tailoring of the repair according to intraoperative active movement with wide awake local anesthesia no tourniquet (WALANT) surgical setting is recommended for better results. We aimed to describe our up-to-date approach to flexor tendon surgery and therapy with the help of visual communication tools of this age. The ideal primary repair of flexor tendons, the management of delayed presentation flexor tendon injuries, the key steps to achieve better results with flexor tendon therapy, and the tele-rehabilitation experience during COVID-19 pandemic will be highlighted. Zone 2 flexor tendon injuries are the most demanding part and will be focused on.

Rehabilitation following surgery for flexor tendon injuries of the hand

BACKGROUND

Various rehabilitation treatments may be offered following surgery for flexor tendon injuries of the hand. Rehabilitation often includes a combination of an exercise regimen and an orthosis, plus other rehabilitation treatments, usually delivered together. The effectiveness of these interventions remains unclear.

OBJECTIVES

To assess the effects (benefits and harms) of different rehabilitation interventions after surgery for flexor tendon injuries of the hand.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, MEDLINE, Embase, two additional databases and two international trials registries, unrestricted by language. The last date of searches was 11 August 2020. We checked the reference lists of included studies and relevant systematic reviews.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs that compared any postoperative rehabilitation intervention with no intervention, control, placebo, or another postoperative rehabilitation intervention in individuals who have had surgery for flexor tendon injuries of the hand. Trials comparing different mobilisation regimens either with another mobilisation regimen or with a control were the main comparisons of interest. Our main outcomes of interest were patient-reported function, active range of motion of the fingers, and number of participants experiencing an adverse event.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data, assessed risk of bias and assessed the quality of the body of evidence for primary outcomes using the GRADE approach, according to standard Cochrane methodology.

MAIN RESULTS

We included 16 RCTs and one quasi-RCT, with a total of 1108 participants, mainly adults. Overall, the participants were aged between 7 and 72 years, and 74% were male. Studies mainly focused on flexor tendon injuries in zone II. The 17 studies were heterogeneous with respect to the types of rehabilitation treatments provided, intensity, duration of treatment and the treatment setting. Each trial tested one of 14 comparisons, eight of which were of different exercise regimens. The other trials examined the timing of return to unrestricted functional activities after surgery (one study); the use of external devices applied to the participant to facilitate mobilisation, such as an exoskeleton (one study) or continuous passive motion device (one study); modalities such as laser therapy (two studies) or ultrasound therapy (one study); and a motor imagery treatment (one study). No trials tested different types of orthoses; different orthosis wearing regimens, including duration; different timings for commencing mobilisation; different types of scar management; or different timings for commencing strengthening. Trials were generally at high risk of bias for one or more domains, including lack of blinding, incomplete outcome data and selective outcome reporting. Data pooling was limited to tendon rupture data in a three trial comparison. We rated the evidence available for all reported outcomes of all comparisons as very low-certainty evidence, which means that we have very little confidence in the estimates of effect. We present the findings from three exercise regimen comparisons, as these are commonly used in clinical current practice. Early active flexion plus controlled passive exercise regimen versus early controlled passive exercise regimen (modified Kleinert protocol) was compared in one trial of 53 participants with mainly zone II flexor tendon repairs. There is very low-certainty evidence of no clinically important difference between the two groups in patient-rated function or active finger range of motion at 6 or 12 months follow-up. There is very low-certainty evidence of little between-group difference in adverse events: there were 15 overall. All three tendon ruptures underwent secondary surgery. An active exercise regimen versus an immobilisation regimen for three weeks was compared in one trial reporting data for 84 participants with zone II flexor tendon repairs. The trial did not report on self-rated function, on range of movement during three to six months or numbers of participants experiencing adverse events. The very low-certainty evidence for poor (under one-quarter that of normal) range of finger movement at one to three years follow-up means we are uncertain of the finding of zero cases in the active group versus seven cases in the immobilisation regimen. The same uncertainty applies to the finding of little difference between the two groups in adverse events (5 tendon ruptures in the active group versus 10 probable scar adhesion in the immobilisation group) indicated for surgery. Place and hold exercise regimen performed within an orthosis versus a controlled passive regimen using rubber band traction was compared in three heterogeneous trials, which reported data for a maximum of 194 participants, with mainly zone II flexor tendon repairs. The trials did not report on range of movement during three to six months, or numbers of participants experiencing adverse events. There was very low-certainty evidence of no difference in self-rated function using the Disability of the Arm, Shoulder and Hand (DASH) functional assessment between the two groups at six months (one trial) or at 12 months (one trial). There is very low-certainty evidence from one trial of greater active finger range of motion at 12 months after place and hold. Secondary surgery data were not available; however, all seven recorded tendon ruptures would have required surgery. All the evidence for the other five exercise comparisons as well as those of the other six comparisons made by the included studies was incomplete and, where available, of very low-certainty.

AUTHORS' CONCLUSIONS

There is a lack of evidence from RCTs on most of the rehabilitation interventions used following surgery for flexor tendon injuries of the hand. The limited and very low-certainty evidence for all 14 comparisons examined in the 17 included studies means that we have very little confidence in the estimates of effect for all outcomes for which data were available for these comparisons. The dearth of evidence identified in this review points to the urgent need for sufficiently powered RCTs that examine key questions relating to the rehabilitation of these injuries. A consensus approach identifying these and establishing minimum study conduct and reporting criteria will be valuable. Our suggestions for future research are detailed in the review.

A Modified Flexor Tendon Suture Technique Combining Kessler and Loop Lock Flexor Tendon Sutures

OBJECTIVES

In the present study, a novel single knot tenorrhaphy was developed by combining the modified Kessler flexor tendon suture (MK) with the loop lock technique.

METHODS

A total of 48 porcine flexor digitorum profundus tendons were collected and randomly divided into six groups. The tendons were transversely cut and then repaired using six different techniques, the MK method, double knot Kessler-loop lock flexor tendon suture (DK), and single knot Kessler-loop lock flexor tendon suture (SK), each in combination with the epitendinous suture (P), and the same three techniques without P. Furthermore, by performing the load-to-failure tests, the biomechanical properties and the time taken to complete a repair, for each tenorrhaphy, were assessed.

RESULTS

Compared to the MK+P method, DK+P was more improved, thereby enhancing the ultimate tensile strength. The SK+P method, which required fewer knots than DK+P, was easier to perform. Moreover, the SK+P repair increased the force at a 2-mm gap formation, while requiring lesser knots than DK+P.

CONCLUSION

As opposed to the traditional MK+P method, the SK+P method was improved and exhibited better biomechanical properties, which may facilitate early mobilization after the repair.

Beyond the Core Suture: A New Approach to Tendon Repair

Despite significant improvements in zone II flexor tendon repair over the last 2 decades, function-limiting complications persist. This article describes 2 novel repair techniques utilizing flexor digitorum superficialis (FDS) autografts to buttress the flexor digitorum profundus (FDP) repair site without the use of core sutures. The hypothesis being that the reclaimed FDS tendon autograft will redistribute tensile forces away from the FDP repair site, increasing overall strength and resistance to gapping in Zone II flexor tendon injuries compared with the current clinical techniques.

Methods

Two novel FDP repair methods utilizing portions of FDS have been described: (1) asymmetric repair (AR), and (2) circumferential repair. Ultimate tensile strength and cyclical testing were used to compare novel techniques to current clinical standard repairs: 2-strand (2-St), 4-strand (4-St), and 6-strand (6-St) methods. All repairs were performed in cadaveric sheep tendons (n = 10/group), by a single surgeon.

Results

AR and circumferential repair techniques demonstrated comparable ultimate tensile strength to 6-St repairs, with all 3 of these techniques able to tolerate significantly stronger loads than the 2-St and 4-St repairs (P < 0.0001). Cyclical testing demonstrated that AR and circumferential repair were able to withstand a significantly higher total cumulative force (P < 0.001 and P = 0.0064, respectively) than the 6-St, while only AR tolerated a significantly greater force to 2-mm gap formation (P = 0.042) than the 6-St repair.

Conclusion

Incorporating FDS as an autologous graft for FDP repair provides at least a comparable ultimate tensile strength and a significantly greater cumulative force to failure and 2-mm gap formation than a traditional 6-St repair.

Plastic surgery procedure unit: A streamlined care model for minor and intermediate procedures: A cost-benefit analysis

INTRODUCTION

The advent of wide-awake local anaesthesia has led to a reduced need for main theatre for trauma and elective plastic procedures. This results in significant cost-benefits for the institution. This study aims to show how a dedicated 7 days/ week plastic surgery procedural (PSP) unit, performing both elective and trauma surgeries, can lead to significant cost-benefits for the institution.

METHODS

Retrospective review of all cases performed in the PSP unit between 1 September and 31 August 2018. We utilised hospital directory admissions data and the hospital's intranet operating theatre system to calculate hospital days saved. Cost analysis was performed using Saolta financial data.

RESULTS

A total of 3058 operations were performed. Of these operations, 2388 cases were elective and 670 were trauma cases. The average waiting time for trauma cases for main operating theatre was 1.4 days, saving a total of 487 hospital days. The total savings associated with hospital bed days were €347,861. The estimated resource savings from performing a procedure in PSP compared with main theatre with regional anaesthesia were €529.00 and €391.00 without regional anaesthesia. The cost saved due to resources was therefore €337,226. The total cost-benefit associated with performing surgeries in PSP including hospital days and resources saved was calculated as €685,087.

CONCLUSION

This study shows the benefit of performing elective and trauma operations in minor procedure units such as PSP. PSP results in a more efficient service, reducing waiting times for surgery, shorter hospital stay, reduced operating cost and an overall significant cost saving.

Wide-Awake Surgery With Local Anesthesia and Epinephrine Is Safe

Hand and upper extremity surgery performed with the patient wide awake involves the use of a local anesthetic and epinephrine. Controversy persists as to whether epinephrine is safe for use in the hand. The goal of this study was to evaluate the safety of epinephrine in hand and upper extremity surgery. The hypothesis was that epinephrine is safe and can be used for a wide breadth of surgical procedures of the hand and upper extremity. A 4-year retrospective chart review was conducted of consecutive patients undergoing wide-awake surgery performed by 2 surgeons at a single institution. All procedures were performed with local anesthesia and epinephrine. Data collected included patient demographics, procedure volume, procedure type, surgical setting, and complications related to epinephrine use. During the study period, 4054 consecutive patients underwent 4287 wide-awake procedures with local anesthesia and epinephrine. Average patient age was 59 years, and 64% of patients were female. No complications occurred as a result of the use of epinephrine, and no tissue necrosis, phentolamine reversal, anaphylaxis, or readmissions occurred. No patients required conversion to general anesthesia or monitored anesthesia care. This analysis of more than 4000 consecutive patients undergoing wide-awake hand and upper extremity surgery with epinephrine confirmed that epinephrine use is safe, with no reported cases of tissue necrosis, reversal, readmission, anaphylaxis, or anesthetic conversion. Epinephrine is safe for use in the hand and upper extremity for patients undergoing wide-awake hand surgery with a local anesthetic. [Orthopedics. 2020;43(6):e529-e532.].

Multilevel Dysvascular Injury of the Hand: Replantation versus Revision Amputation

BACKGROUND

Multilevel dysvascular injury of the hand can be treated with replantation or revision amputation. The authors compared both modalities regarding functional outcomes, patient-reported outcomes, and required resources, as relevant studies are scarce.

METHODS

In this retrospective review of consecutive case series (replantation, n = 8; revision amputation, n = 11), clinical results and functional outcomes (including grip strength, range of motion, sensory recovery, and grip or pinch ability) were assessed. Patient-reported outcomes, required hospital resources, and treatment cost until 1 year after surgery were compared between both groups.

RESULTS

Six patients used passive prostheses, two used body-powered prostheses, and three did not use a prosthesis in the revision amputation group. All patients in the replantation group could grip objects and had restored hands, with protective sensory recovery and substantial wrist motion, whereas six patients in the revision amputation group were unable to grip or pinch objects. Replantation was associated with superior patient-reported outcomes, but required more hospital resources and treatment costs.

CONCLUSIONS

This study suggests that in the treatment of multilevel dysvascular injury of the hand, the surgical method should be chosen on a case-by-case basis. For better functional and patient-reported outcomes, replantation is preferred. Revision amputation can be performed in the absence of sufficient hospital resources and to reduce treatment cost. These findings can aid in the preoperative counseling of patients with multilevel dysvascular injury of the hand.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Pulley Release and Reconstruction With Acellular Dermal Matrix After Zone 2 Flexor Tendon Injury

Zone 2 flexor tendon repair has been historically associated with poor outcomes, mainly due to stiffness. In an effort to minimize adhesions, accommodate flexor digitorum profundus and flexor digitorum superficialis bulk, and prevent bowstringing, we have developed a novel approach to flexor tendon repair that relies on aggressive flexor tendon pulley release and pulley reconstruction with acellular dermal matrix. This technique leverages the antiadhesive properties and high tensile strength of acellular dermal matrix to maximize gliding and prevent bowstringing. Here we describe the details of our technique and illustrate a case where this technique was employed.

Closed traumatic avulsion of both ring finger flexors with successful primary repair more than 4 weeks after injury and a review of the literature

Closed flexor digitorum profundus (FDP) tendon avulsions are a recognized injury in hand surgery. However, closed tendon avulsion of both flexor tendons in the same digit is rare, with the few cases reported in the literature and presented here. Management includes primary repair ideally within the first 2 weeks to achieve optimal outcome. While beyond 4 weeks a two-stage repair is the dictum, we present a case where both tendons were avulsed but primary repair of the FDP was possible more than 4 weeks after the injury, with a good outcome. This case highlights that primary tendon repair at 32 days, the longest noted in the literature in this group of patients, can result in a good outcome even if the injury is more than 4 weeks old. However, good intraoperative decision-making is key and the skillset must be present for conversion to a two-stage repair if necessary.

[Flexor tendon injuries of the hand]

Flexor tendon injuries of the hand are relatively rare but pose significant challenges to both physician and patient. A thorough clinical evaluation enables flexor tendon lacerations to be identified and classified. The flexor tendons of the hand are divided into five anatomic zones (from distal to proximal). Diagnostics, treatment and prognosis may differ depending on which zone is affected. Early, careful and proficient management is needed to ensure good functional outcomes. Various factors influence the outcome, including location, mechanism of injury, presence of concomitant injuries, time of surgery, quality of tendon repair and the rehabilitation protocol. It is important to inform the patient about the importance of thorough rehabilitation and possible complications. Postoperative scarring and adhesions, infections and secondary tendon ruptures due to insufficient primary repairs are especially challenging and potentially necessitate a lengthy and strenuous secondary repair and rehabilitation process.

Tenolysis rate after zone 2 flexor tendon repairs

Objectives

This study aims to evaluate the tenolysis rates of zone 2 flexor digitorum profundus (FDP) with flexor digitorum superficialis (FDS) tendon repairs using four-strand technique and early passive motion exercises.

Patients and methods

In this retrospective study, we performed zone 2 flexor tendon repairs in 149 patients (117 males, 32 females, mean age 33.3±12.9 years; range, 13 to 72 years) (82 right and 67 left hands) between November 2014 and January 2019. A total of 194 FDP and FDS tendons were repaired primarily by using modified Kessler and Bunnell methods. Patients underwent pure passive motion protocols after surgery according to modified Duran’s protocol. No active flexion components were added until postoperative fourth week.

Results

Twenty-three out of 149 patients and 28 out of 194 fingers (14.43%) had tenolysis. There was no significant relationship between the number of operated fingers, gender, and tenolysis rate (p=0.836, p=0.584, respectively).

Conclusion

The repair of the FDP with FDS tendon increases the tenolysis rate in zone 2. The tenolysis rate does not change according to the number or distribution of injured fingers and gender of the patient.

Effects of a Q Suture Technique on Resistance to Gap Formation and Tensile Strength of Repaired Tendons: An Ex Vivo Mechanical Study

PURPOSE

The repair of digital flexor tendons following laceration should aim to prevent gapping at the repair site and restore the tensile strength of the tendons to facilitate postoperative movement. We present here a simple Q suture and test its effects on gap formation and tensile strength of the repaired tendons.

METHODS

Sixty porcine tendons were repaired with 3 2-strand sutures (Kessler, Kessler plus 2Q, and Kessler plus running sutures) and 3 4-strand sutures (double Kessler, double Kessler plus 2Q, and double Kessler plus running sutures). The specimens were subjected to a cyclic loading. At each cycle, the number of tendons that initiated gapping or formed a 2-mm gap at the repair site was determined. After the cyclic load testing, the gap distance between tendon ends and the ultimate strength of the repaired tendons was measured.

RESULTS

In both 2-strand and 4-strand tendon repairs, augmentation by insertion of the 2Q sutures reduced the number of tendons that showed 2-mm gaps ends during loading. Compared with the single Kessler and Kessler plus running sutures, Kessler plus 2Q suture significantly increased the ultimate strength of the tendon repair. Compared with the double Kessler and double Kessler plus running sutures, double Kessler plus 2Q suture significantly decreased the gap distance at the repair site after cyclic loading.

CONCLUSIONS

The Q suture technique effectively enhances the resistance to gap formation of 2-strand and 4-stand tendon repair. It also improves the tensile strength of 2-strand Kessler repairs.

CLINICAL RELEVANCE

The Q suture is a simple technique that can resist gap formation and strengthen the tensile strength of the repaired tendons in the laboratory setting.

Practical Tips to Improve Efficiency and Success in Upper Limb Replantation

LEARNING OBJECTIVES

After reading this article, participant should be able to: 1. Describe the technique of replantation for very distal amputation of the digit and salvage procedures for venous drainage. 2. Perform single-digit replantation after viewing the videos. 3. Recognize appropriate cases for joint salvage techniques in periarticular amputation at each joint of the digit and wrist. 4. Outline the methods of flexor and extensor tendon reconstruction in an avulsed amputation of the digit or thumb. 5. Understand the order of digital replantation and transpositional replantation for a restoration of pinch or grip in multiple-digit amputation.

SUMMARY

This article provides practical tips and caveats for the latest replantation surgical techniques for digit, hand, and upper extremity amputation. Four videos, clinical photographs, and drawings highlight important points of operative technique and outcomes of replantation.

[Postoperative treatment and rehabilitation following flexor tendon injuries]

BACKGROUND

The ideal surgical and postoperative treatment for flexor tendon injuries, especially in zone 2, is still subject to continuous modifications and professional discussions.

OBJECTIVE

Presentation of established rehabilitation concepts, specific problems and new treatment approaches with practical recommendations for application.

MATERIAL AND METHODS

Comparison of commonly used treatment concepts by assessing surgical flexor tendon repair, splint choice and clinical application in patients. Discussion of new surgical approaches and standards and their influence on postoperative therapy after flexor tendon injuries.

RESULTS

The Washington regimen has retained its status as the standard in the current follow-up treatment of flexor tendon injuries. New suture materials and techniques enable early active rehabilitation of sutured flexor tendons with good clinical results, such as increased range of motion for interphalangeal joint extension and improved distal interphalangeal joint flexion with overall acceptable frequencies of suture rupture.

CONCLUSION

A stable tendon repair with smooth gliding is the foundation for treatment after flexor tendon injuries. After intraoperative active digital extension-flexion testing of the sutured tendon an early active rehabilitation approach should follow. New splint designs in combination with primary stable tendon suture techniques have the potential to improve the postoperative outcome, presupposing a reliable cooperation of the patient.