Retained wooden splinter migrated within a digital flexor tendon sheath: Ultrasonographic diagnosis for presurgical planning

A 29-year-old right-handed woman presented to an outside emergency department with right small finger pain, swelling, and concern for a retained wooden splinter. Diagnosis and treatment were delayed for 2 weeks due to the inability to identify the foreign body clinically or radiographically. Ultimately, ultrasonography by a fellowship-trained specialist was used to localize the wooden splinter. It was embedded within the flexor tendon sheath but had migrated away from its initial point of entry. The patient underwent subsequent surgical extraction, irrigation, and debridement. Two weeks following surgery, she had regained full range of motion through her digit without signs of infection. This case highlights the use of diagnostic ultrasound to identify a radiolucent foreign body, such as a wooden splinter, and to guide subsequent surgical extraction.

Is arthritis an associated risk factor for trigger finger occurrence after carpal tunnel release? A nationwide, population-based study in Korea

PURPOSE

We hypothesized that increased friction between the flexor tendon and surrounding structures due to hand arthritis is an important risk factor for trigger finger (TF) after carpal tunnel release (CTR). Therefore, we compared TF development according to the presence or absence of arthritis in carpal tunnel syndrome (CTS) patients treated with CTR.

METHODS

This retrospective study was based on data collected from the National Health Insurance Service-National Sample Cohort (NHIS-NSC) in the Republic of Korea between January 1, 2002, and December 31, 2015. Patients diagnosed with TF between one month and one year after the CTR date or with a history of surgery were included in the study. During subsequent follow-up, the patients were divided into subgroups of those (1) with TF and (2) without TF. Sex, age, arthritis, and TF-related comorbidities were compared between the subgroups.

RESULTS

The subgroup with TF had a higher proportion of women (9.43% vs 90.57%), the highest age range between 50 and 59 years, more cases of arthritis (32.55% vs 16.79%), and a higher proportion of patients with hypothyroidism (10.85% vs 4.60%) than the group without TF. The association between arthritis and TF after CTR was examined using a multivariate logistic regression model, showing arthritis to be a significant risk factor for TF after CTR (odds ratio, 1.35; P = 0.049).

CONCLUSIONS

We identified arthritis as an important risk factor for the development of TF after CTR.

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.

[Comparison between different anchors for zone I flexor tendon repair]

INTRODUCTION

Transosseous reinsertion has been used to complement the Bunnell pull-out technique in the repair of zone I deep flexor tendon injuries. The aim of this study is to compare the different devices on the market in terms of complication, functional recovery and ease of use.

MATERIAL AND METHOD

This is a single-center study including all patients who underwent transosseous anchor reinsertion from 2010 to 2021 with a minimum of 6 months of follow-up. Twenty-seven patients were included. The anchors used were of different types: Microfix® Quickanchor plus® and Miniquick anchor® from DePuy Mitek; Juggerknot® Soft Anchor 1.0mm from Zimmer-Biomet; or Kerifix® 4.0 from KeriMedical. We analyzed intraoperative data, complications and functional recovery by quickDASH score.

RESULTS

The average age was 38.6 years (± 16.1), the demographic characteristics were identical in the different groups. There was a significant difference in the number of anchors used intraoperatively before definitive placement (P=0.02), to the disadvantage of the Juggerknot® anchors. There was no significant difference in terms of complications and functional recovery evaluated by the quickDASH.

CONCLUSION

Our study did not find significant differences between the different anchors in terms of complications and functional recovery. Some anchors seem to have a better grip during placement than others.

Healing strength of tendon repair with or without knots between two tendon ends and histological changes in a chicken model

We studied the healing strength and histological changes of digital flexor tendons repaired using Kessler (core suture knots placed over the tendon surface) and modified Kessler (core suture knots placed between two tendon ends) in 31 long toes of chicken. Four weeks after surgery, the healing tendons were measured in a tensile testing machine, and the adhesion formation and histological changes were observed. The strength of the Kessler repairs was significantly greater than that of the modified Kessler repairs with a 35% mean difference. No significant difference was found between the adhesion scores of the tendons repaired with both techniques. In histological sections, the arrangement of collagen fibers in the modified Kessler repair group was more disordered. We conclude that the tendons repaired with the Kessler method are stronger than those with the modified Kessler technique. The knots between tendon ends are detrimental to the early healing strength of digital flexor tendons.

Morphological, histological and biomechanical comparison of bone marrow aspirate concentrate, micro-fragmented adipose tissue and platelet-rich plasma in prevention of tendon adhesion

BACKGROUND

Flexor tendon repair often leads to peritendinous adhesions, reducing finger motion and hand function. This study compares the effects of stromal cells from different sources and platelet-rich plasma (PRP) on adhesion formation after tendon repair.

METHODS

Forty rabbits had their flexor digitorum profundus tendons transected and repaired with a modified Kessler suture technique. The control group received an isotonic solution. PRP, bone marrow aspirate concentrate (BMAC), and micro-fragmented adipose tissue (MFAT) were injected in groups 2, 3, and 4, respectively. Rabbits wore casts for 2 weeks. Assessments included morphology, histopathology, range of motion (ROM), and biomechanical testing at the 3rd and 8th weeks.

RESULTS

At 3 weeks, the BMAC group had the thickest and longest adhesions, the highest Tang Score, and inflammation score. However, at 8 weeks, the BMAC group had the lowest Tang Score and inflammation score. ROM was higher in the PRP group at 3 weeks and BMAC group at 8 weeks. No significant differences were found between BMAC and MFAT groups in adhesion measurements. Biomechanical parameters were higher in BMAC and MFAT groups at 8 weeks compared to control.

CONCLUSION

BMAC therapy after primary flexor tendon repair improves adhesion formation and maintains ROM. It also enhances the biomechanical properties of the flexor tendon during the later stages of healing.

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.

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.

Multiple flexor tendon ruptures due to osteochondroma of the hamate: A case report

BACKGROUND

Closed rupture of the little and ring finger flexor tendons caused by the hamate is mostly associated with a fracture or nonunion of the hamate hook. Only one case of a closed rupture of the finger flexor tendon caused by osteochondroma in the hamate has been reported. Here, we present a case study to highlight the possibility of hamate osteochondroma as a rare cause of finger closed flexor tendon rupture based on our clinical experience and literature review.

CASE SUMMARY

A 48-year-old man who had been a rice-field farmer for 7–8 h a day for the past 30 years visited our clinic due to the loss of right little finger and ring finger flexion involving both the proximal and distal interphalangeal joints. The patient was diagnosed with a complete rupture of the ring and little finger flexors because of the hamate and was pathologically diagnosed with an osteochondroma. Exploratory surgery was performed, and a complete rupture of the ring and little finger flexors due to an osteophyte-like lesion of the hamate was observed, which was pathologically diagnosed as an osteochondroma.

CONCLUSION

One should consider that osteochondroma in the hamate may be the cause of closed tendon ruptures.

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.

Knotless Tendon Repair with a Resorbable Barbed Suture: An In-vivo Comparison in the Turkey Foot

Background: Un-knotted barbed suture constructs are postulated to decrease repair bulk and improve tension loading along the entire repair site resulting in beneficial biomechanical repair properties. Applying this repair technique to tendons has shown good results in ex-vivo experiments previously but thus far no in-vivo study could confirm these. Therefore, this current study was conducted to assess the value of un-knotted barbed suture repairs in the primary repair of flexor tendons in an in-vivo setting. Methods: Two groups of 10 turkeys (Meleagris gallapovos) were used. All turkeys underwent surgical zone II flexor tendon laceration repairs. In group one, tendons were repaired using a traditional four-strand cross-locked cruciate (Adelaide) repair, while in group two, a four-strand knotless barbed suture 3D repair was used. Postoperatively repaired digits were casted in functional position, and animals were left free to mobilise and full weight bear, resembling a high-tension post-op rehabilitation protocol. Surgeries and rehabilitations went uneventful and no major complications were noted. The turkeys were monitored for 6 weeks before the repairs were re-examined and assessed against several outcomes, such as failure rate, repair bulk, range of motion, adhesion formation and biomechanical stability. Results: In this high-tension in-vivo tendon repair experiment, traditionally repaired tendons performed significantly better when comparing absolute failure rates and repair stability after 6 weeks. Nevertheless, the knotless barbed suture repairs that remained intact demonstrated benefits in all other outcome measures, including repair bulk, range of motion, adhesion formation and operating time. Conclusions: Previously demonstrated ex-vivo benefits of flexor tendon repairs with resorbable barbed sutures may not be applicable in an in-vivo setting due to significant difference in repair stability and failure rates. Level of Evidence: Level IV (Therapeutic).

Zone 1 and 2 flexor tendon repair via a longitudinal incision crossing the volar distal interphalangeal joint: functional and cosmetic outcomes

INTRODUCTION

The primary aim of this study was to present patient-reported functional outcomes after zone 1 and 2 flexor tendon repair using a novel longitudinal volar approach crossing the distal interphalangeal joint (DIPJ) perpendicularly. The secondary aims were to investigate the cosmetic outcomes, satisfaction and complication rates associated with this technique.

METHODS

Over a 6-year period, 75 patients underwent flexor tendon repair using this technique. The quick version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH), five-level EQ-5D (EQ-5D-5L), Patient and Observer Scar Assessment Scale (POSAS) and satisfaction questionnaires were collected. QuickDASH scores were available for 59 patients (79%), and POSAS scores were available for 45 patients (60%) at a mean follow-up of 48 months. Concomitant nerve repairs were undertaken in 24 cases.

RESULTS

The median QuickDASH score was 4.5 (interquartile range [IQR] 1.1-12.5) and median POSAS score was 12 (IQR 8-16). No significant difference was observed in median QuickDASH score between patients with and without a concomitant nerve repair (4.5 vs 6.8; p = 0.36). Fifty-six patients (94%) were satisfied. Two patients required open tenolysis, and a single case of early re-rupture occurred that required revision open repair.

CONCLUSIONS

Utilising validated patient-reported functional outcomes, this study demonstrated that a direct longitudinal incision over the DIPJ for zone 1 and 2 flexor tendon repairs can result in excellent functional and cosmetic outcomes, with high rates of patient satisfaction and low rates of complications. This challenges previously held dogma that longitudinal incisions crossing flexion creases should be avoided.

The Clinical Efficacy of Fat Injection on the Repair of Hand Flexor Tendon: A Randomized Clinical Trial

Background

In recent years, special attention has been paid to minimally invasive and conservative methods in addition to conventional surgical methods to repair tendon damage. In this regard, the effect of fat injection and graft has been of great interest due to its potential in accelerating tissue repair. We aimed to assess the clinical efficacy of fat injection along with conventional approach in patients with flexor tendon injury.

Methods

In this randomized clinical trial, 64 patients were randomly scheduled for tendon repair using the usual modified Kessler four-strand method alone or tendon repair using four-strand method and fat injection on the proximal and distal sides of the repair site in the Hazrat Fatemeh Hospital, Tehran Province, Iran in 2022 (IRCT20221206056723N1). Patients were followed-up for eight weeks regarding the function status of the repaired tendon (using Strickland grading test), range of motion (by physical examination) and flexion and extension gaps (by imaging).

Results

In the eighth weeks after the treatment, the average Strickland score was significantly higher in the group receiving fat injection (P: 0.009 ). In the two pointed times, the mean range of motion was significantly higher and the mean flexion and extension gaps were significantly lower in those who received fat injection. None of the procedural side effects were observed in the fifth and eighth weeks after the treatment.

Conclusion

Fat injection along with usual surgical treatment for tendon repair accelerates and improves tendon function and range of motion.

Closed flexor pulley injuries: A literature review and current practice

Background

Closed flexor pulley injuries are a clinical entity of great interest in hand surgery, and these lesions could be observed mainly in rock-climbing athletes.

Objective

An extensive literature search of PubMed, SCOPUS, Cochrane Library, and Web of Sciences databases on closed finger pulley rupture, related treatments, and outcomes were performed. All relevant information was used in this literature review.

Conclusions

Many athletes are potentially exposed to these uncommon injuries. Therefore, these lesions require careful examination and a high index of suspicion to confirm the diagnosis and identify the degree of soft tissue injury, particularly in patients not involved in sporting activities. The data summarized in this literature review demonstrated that according to Schöffl's classification, conservative treatment should be indicated for low-grade injuries (grade 1 or 2), whereas surgical treatment should be performed in patients with more severe acute injuries (grade 4). Grade 3 flexor pulley injuries lie in a grey area where conservative and surgical treatment may give good clinical and return-to-sport patient results.

Effect of a Text Message-Based Support Program on Outcomes of Patients After Flexor Tendon Injury Repair

PURPOSE

Although the effectiveness of using text messages in home-based rehabilitation programs has been investigated, its ability to engage patients in home rehabilitation exercises and, as a result, improve hand outcomes, specifically in patients with flexor tendon injuries, has not been evaluated. The aim of this study was to determine whether the addition of a text message-based intervention to usual care is effective in improving hand outcomes in patients with flexor tendon injuries after repair.

METHODS

In this 2-arm parallel randomized controlled trial, 40 patients were randomly assigned to either the intervention group (usual care plus the support program) or the control group (usual care only). Intervention included an automated package of instructional text messages containing links to a secure website for instructional rehabilitation videos delivered over 12 weeks. The Quick Disabilities of the Arm, Shoulder, and Hand and visual analog scale for pain scores were assessed at 6 and 12 weeks. Physician-reported grip strength and total active motion were assessed after 12 weeks.

RESULTS

The study was completed by 90% (36 of 40) of the patients who were enrolled. There were statistically significant differences between the 2 groups with respect to Quick Disabilities of the Arm, Shoulder, and Hand and visual analog scale scores at the 6-week and 12-week assessments. In addition, there were statistically significant differences between the 2 groups with respect to total active motion and grip strength at 12 weeks. Finally, a high level of satisfaction with the intervention was reported.

CONCLUSIONS

The text message-based program was associated with improved outcomes over the first 12 weeks after flexor tendon repair.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

The Evaluation of a Flexor Digitorum Profundus-to-Volar Plate Zone I Repair Versus Button Repair: An In vitro Biomechanics Study

PURPOSE

The purpose of the study was to evaluate joint kinematics and tendon work of flexion (WOF) following a flexor digitorum profundus (FDP)-to-volar plate (VP) repair technique relative to a pullout button for zone I flexor tendon injuries.

METHODS

Fourteen digits were tested using an in vitro active finger motion simulator under 3 repaired conditions following a simulated zone I avulsion: button, FDP-VP, and "no slack" FDP-VP (corrected for additional VP length). Outcome metrics included active joint range of motion (ROM), fingertip strength, FDP and flexor digitorum superficialis tensile loads, and WOF.

RESULTS

The button and FDP-VP techniques restored WOF to the intact condition for FDP and flexor digitorum superficialis. All repairs restored distal interphalangeal joint ROM and kinematics to the intact condition. Similarly, all repairs restored WOF; however, the "no slack" FDP-VP significantly increased WOF by 10% to 12% over the simple FDP-VP repair. The button technique had similar fingertip strength to the intact condition, whereas the FDP-VP repairs significantly reduced peak fingertip strength from intact, albeit only 1-2 N compared with the button repair.

CONCLUSION

In this in vitro cadaveric model, the button and FDP-VP techniques restored WOF and ROM to within intact levels, with no difference between these repairs in all measured outcome metrics.

CLINICAL RELEVANCE

Based on its initial strength and its equal biomechanical performance compared with the button repair, the FDP-VP technique may be a viable option for treating FDP avulsions.

Effectiveness of Sodium Hyaluronate and ADCON-T/N for the Prevention of Adhesions in Hand Flexor Tendon Surgery: A Systematic Review and Meta-Analysis

PURPOSE

A common complication after digital flexor tendon repair in the hand is postoperative adhesions that can cause loss of motion and compromise hand function. The aim of this review of relevant published literature was to assess the effectiveness of locally administered sodium hyaluronate or ADCON-T/N for the prevention of adhesions after hand flexor tendon repair.

METHODS

A literature search was conducted in June 2020 in multiple databases for randomized controlled trials . Our primary outcome was measurement of active finger motion. Follow-up was defined as short-term (< 12 weeks), mid-term (12 weeks to 6 months) and long-term (> 6 months). Mean differences (MD) and standardized mean differences (SMD) of total active motion (TAM) of the interphalangeal joints (IPJs) and active motion of the IPJs separately were calculated where results were meta-analyzed.

RESULTS

Six randomized controlled trials were included. For ADCON-T/N, no benefits were detected for TAM of the IPJs (MD 1.71 [-21.54, 24.96]) or active motion of the IPJs separately (proximal: MD 4.77 [-4.47, 14]; distal: MD 1.17 [-10.33, 12.66]) in the short-/mid-term. The mid-term benefit in TAM of sodium hyaluronate over standard care (placebo/no treatment) did not reach statistical significance (SMD 0.31 [0, 0.63]); however, a subgroup comparison of repeated administration of sodium hyaluronate versus standard care was both statistically and clinically significant (SMD 0.55 [0.11, 0.98]).

CONCLUSIONS

Repeated administration of sodium hyaluronate at the tendon repair site may be effective in improving postoperative active finger motion after primary hand flexor tendon repair in the mid-term.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

The Impact of Social Deprivation and Hand Therapy Attendance on Range of Motion After Flexor Tendon Repair

PURPOSE

To examine the influence of social deprivation and hand therapy attendance on active range of motion (AROM) outcomes following flexor tendon repair.

METHODS

We performed a retrospective analysis of patients who underwent primary zone I-III flexor tendon repair between November 2016 and November 2020. Area deprivation index (ADI) was used to quantify social deprivation. Medical record review determined each patient's demographic characteristics, injury details, total hand therapy visits, and final AROM outcome. Active range of motion was converted to Strickland's percentage for analysis. Spearman correlation and simple and multivariable linear regression models were used to assess relationships between explanatory variables and outcomes.

RESULTS

There were a total of 109 patients, with a mean ADI of 53 and mean therapy attendance of 13 visits. Higher ADI and lower therapy attendance were correlated, and each was associated with significantly decreased Strickland's percentage. In the multivariable model, therapy attendance, ADI, zone 2 injury, and age maintained significant associations with Strickland's percentage.

CONCLUSIONS

Socially deprived patients attend fewer therapy sessions and obtain poorer AROM after flexor tendon repair. Social deprivation is likely to contribute to poor outcomes both by its association with decreased therapy attendance and by other potential pathways that make it difficult for deprived patients to achieve good surgical outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Diagnostic ultrasound of tendon injuries in the setting of distal radius fractures

OBJECTIVE

Describe tendon injuries and their structural causes seen on ultrasound in wrists with distal radius fractures and estimate the accuracy of ultrasound and its impact on clinical management.

MATERIALS AND METHODS

Ultrasounds of 226 wrists (221 patients) with distal radius fractures were retrospectively reviewed. Ultrasound findings of tendon injuries and their structural causes were correlated with surgery and clinical outcome. Accuracy and inter- and intra-observer reproducibilities were calculated.

RESULTS

Twenty-five wrists were treated non-operatively while 201 underwent surgery. Ultrasound demonstrated hardware contact with flexor pollicis longus (FPL) in 76 wrists, extensor pollicis longus (EPL) in 21, and other tendons in 94. Ultrasound identified tendon ruptures in 23 wrists (13 EPL/8 FPL/2 extensor indicis proprius (EIP)), most of which were surgically confirmed. Among 12 wrists with confirmed EPL ruptures, distal radius fracture had been treated with volar plating in 6 and non-operatively in 6, and ultrasound showed osseous irregularity at the rupture site in 8. All FPL ruptures occurred in wrists with volar plating. Ultrasound findings were concordant with subsequent clinical management in most. In 2, ultrasound findings led to the decision to remove hardware despite lack of symptoms. Ultrasound had sensitivity/specificity/accuracy of 88/99/98% for identifying a specific tendon as ruptured and 88/87/88% for tendon abnormalities in general. Inter- and intra-observer reproducibilities were excellent (kappa = 0.85 ~ 1.0).

CONCLUSION

Certain wrist tendons, particularly EPL and FPL, are vulnerable after distal radius fractures. Ultrasound is accurate and useful for detecting tendon injury and sources of tendon irritation and can guide clinical management.

Investigations into flexor tendon repair: a research journey over three decades

In this article, I review how my team and I addressed clinical concerns in Zone 2 flexor tendon repair, and how major findings in each step of our research were translated into clinical practice. The focus of the article is on the thought processes behind each new investigation, the interpretation of research findings and conclusions drawn from the basic and clinical studies.

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).

Outcome measurement in adult flexor tendon injury: A systematic review

BACKGROUND

Defining the optimal, evidence-based management of flexor tendon injury remains challenging. Lack of consensus on which measures to use to assess the outcome of interventions is a key issue, especially with regard to patient-reported outcome measures (PROMs). This systematic review defines the landscape of outcome measurement in studies on interventions for flexor tendon injuries to guide future research.

METHODS

A PRISMA-compliant systematic review was conducted using bespoke search strategies applied to MEDLINE, EMBASE, PsycINFO, CENTRAL, CINAHL and AMED. A protocol was developed and registered prospectively (CRD42020186780). We identified all studies describing adult patients undergoing interventions for acute hand flexor tendon injuries.

RESULTS

Of the 4844 studies, 114 studies met the final inclusion criteria for evaluating the outcomes of 8127 participants with 9071 injured digits. Studies included 24 randomised controlled trials, 19 cohort studies and 61 case series. Nine different PROMs were used in 24 studies (22%): three site-specific PROMs, one generic quality-of-life measure and four visual analogue scales. Clinician-reported outcome measures were used in 103 studies (96%), such as the range of motion reported in 102 studies (94%). Adverse outcomes were reported in 96 studies (89%), with the most frequently reported adverse outcomes being tendon rupture and infection. Re-operation was reported in 21 studies (19%). The most frequently reported health economic outcome measure was the length of work absence, reported in ten studies (9%).

CONCLUSIONS

There is variability in the use of outcome measures used to study interventions for flexor tendon injuries. An independent systematic review of the psychometric properties of the identified outcome measures and a specific multi-stakeholder consensus process may support optimal choice and standardisation for future studies.

A Comparison of Outcomes at Twelve Weeks of Traditional Button-Over-Nail versus Bone Anchor Repair of Zone I Flexor Digitorum Profundus Tendon Injury

Background: The repair of zone 1 flexor tendon injury often relies on re-inserting the flexor digitorum profundus (FDP) tendon to the distal phalanx. The aim of this retrospective study is to compare outcomes at 12 weeks following traditional button-over-nail (BON) versus bone anchor (BA) repair of zone I FDP injury. Methods: Patients undergoing zone 1 FDP repair between April 2007 and September 2018 using a BON or a BA were included in the study. Patient demographics, complications, arc of flexion of distal (distal interphalangeal joint [DIPJ]) and proximal interphalangeal joint (PIPJ) and patient-rated outcomes were analysed. Results: Forty-three patients were included in the study: 21 in the BA group and 22 in the BON group. Good function was achieved by 20 patients in BA versus nine in BON. Complications occurred in five BA patients versus 10 BON patients. Patients achieved a mean active DIPJ flexion of 49° and 31° and PIPJ flexion of 92° and 57° in the BA and BON groups, respectively. Conclusion: Our study demonstrates better arc of motion, patient-rated outcomes and lower complications at 12 weeks after surgery in patients undergoing zone 1 FDP repair using a BA. Level of Evidence: Level III (Therapeutic).

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.

Patient-reported outcome measures for patients with hand-specific impairments-A scoping review

BACKGROUND

Patient-reported outcome measures (PROMs) are increasingly used to provide evidence for treatment effects and to guide rehabilitation. To our knowledge, no disease-specific PROM exists for the assessment of patients with flexor tendon lesions of the hand. We believe that PROMs used to assess hand function, regardless of diagnosis, contain relevant items for patients with flexor tendon lesions of the hand.

PURPOSE

The aim of our study was to identify and collect items from pre-existing PROMs used by clinical experts to assess the health status and function in patients with reduced hand function.

STUDY DESIGN

A scoping review searching for PROMs with hand-specific content was conducted to ensure face validity. As these items are assumed to have been through an evaluation process by the clinical specialists, they have the advantage and likelihood of being useful.

METHODS

We searched five bibliographic databases. All PROMs with hand-specific content used to assess hand function were considered for inclusion. Questionnaires written in English, Danish, Swedish, and Norwegian were included. An analysis of content redundancy was conducted, and items were grouped according to The World Health Organization's International Classification of Functioning, Disability and Health.

RESULTS

Seventy-three PROMs were included with a total of 1,582 items. The majority of the items were redundant across measurement instruments, and redundant items were consolidated, resulting in 179 nonredundant items. All nonredundant items were classified according to the International Classification of Functioning, Disability and Health components.

CONCLUSIONS

This review presents a collection of 179 items ensuring face validity for patients with hand-related disease/injury.

Infantile Flexor Tendon Lacerations: Surgical Technique and Illustrative Case

Infantile flexor tendon lacerations are rare, with few cases reported. Surgical intervention in this age group is favorable, but there are several factors that add to the complexity of these injuries, such as small hand anatomy, frequent delays in diagnosis, and difficulties with postoperative rehabilitation. This article describes a 2-strand flexor tendon repair technique in a 10-month-old female infant.

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.

TGF-β3 regulates adhesion formation through the JNK/c-Jun pathway during flexor tendon healing

BACKGROUND

The injured flexor tendon has poor healing ability, which is easy to cause tendon adhesion. It can affect the recovery of tendon function, which is still a long-term and difficult task for surgeons. Transforming growth factor β (TGF-β) has been widely considered to play an important role in flexor tendon repair in recent years.

AIM

This work was to investigate the anti-adhesion and anti-inflammatory effects of TGF-β3 on flexor digitorum longus (FDL) tendon repair rats.

METHOD

Anastomosis models of tendon laceration in the flexion toes of rats were delivered with no treatment, vehicle, or TGF-β3 -overexpressed adenovirus vector (ad-TGF-β3) locally to the injured tendon area from day 3 to 8. Subsequently, the expression of TGF-β3, TGF-β1/2, Smad3, Smad7, JNK, phosphorylation (p)-JNK, c-Jun, and phosphorylation (p)-c-Jun were detected by western blot, the expression of Mmp9 and Mmp2 by RT-qPCR, the Range of motion (ROM) and gliding resistance by adhesion formation testing, the mechanical strength of tendon healing by biomechanical testing, the pathologic changes of flexor tendon tissues by HE staining, the expression of collagen type III by immunohistochemical staining, and the levels of IL-6, TNF-α, COX2 and IL-1β in serum by ELISA, respectively.

RESULTS

Rat models treated with no treatment showed a lower elevation of TGF-β3 and Smad7 expression, and a higher elevation of TGF-β1/2 and Smad3 expression, during day 14 to day 28. Besides, under the treatment of ad-TGF-β3, a significantly increase was reflected in the expression of TGF-β3 and Smad7, ROM, as well as mechanical strength of flexor tendon, whereas significantly reduction was shown in gliding resistance, the content of inflammatory cytokines, the ratio of p-JNK/JNK, p-c-Jun/c-Jun, as well as the expression of TGF-β1/2, Smad3, Mmp9, and Mmp2 genes, as compared to those from vehicle treatment. Meanwhile, TGF-β3 demonstrated a better pathologic recovery process with no obvious necrosis or fracture of collagen fibers. Besides, TGF-β3 revealed a significant reduction of collagen type-III expression in the flexor tendon healing tissues.

CONCLUSION

These findings suggested that TGF-β3 effectively protected against flexor tendon injury via regulating adhesion formation.

Relative motion flexion splinting for the rehabilitation of flexor tendon repairs: A systematic review

Introduction

Relative motion splinting has been used successfully in the treatment of extensor tendon repairs and has recently been applied in flexor tendon rehabilitation. The purpose of this systematic review was to identify articles reporting use of relative motion flexion (RMF) splinting following flexor tendon repair and to examine indications for use and clinical outcomes.

Methods

Seven medical databases, four trials registries and three grey literature sources were systematically searched and screened against pre-specified eligibility criteria. Screening, data extraction and quality appraisal were independently performed by two reviewers.

Results

A total of 12 studies were identified, of which three met the review eligibility criteria: one retrospective case series; one cadaveric proof of concept study; and one ongoing prospective case series. The type of splint (including metacarpophalangeal joint position and available movement), exercise programme, and zone of tendon injury varied between studies. Both case series presented acceptable range of movement and grip strength outcomes. The prospective series reported one tendon rupture and two tenolysis procedures; the retrospective series reported no tendon ruptures or secondary surgeries.

Discussion

We found limited evidence supporting the use of RMF splinting in the rehabilitation of zones I-III flexor tendon repairs. Further prospective research with larger patient cohorts is required to assess the clinical outcomes, patient reported outcomes and safety of RMF splinting in comparison to other regimes. Application of the relative motion principles to flexor tendon splinting varied across the included studies, and we suggest an operational definition of relative motion in this context.

Use of a relative motion flexion orthosis for postoperative management of zone I/II flexor digitorum profundus repair: A retrospective consecutive case series

STUDY DESIGN

A retrospective, single-center, consecutive case series.

INTRODUCTION

In concept, a relative motion flexion (RMF) orthosis will induce a "quadriga effect" on a given flexor digitorum profundus (FDP) tendon, limiting its excursion and force of flexion while still permitting a wide range of finger motion. This effect can be exploited in the rehabilitation of zone I and II FDP repairs.

PURPOSE OF THE STUDY

To describe the use of RMF orthoses to manage zone I and II FDP 4-strand repairs.

METHODS

Medical record review of 10 consecutive zone I and II FDP tendon repairs managed with RMF orthosis for 8 to 10 weeks in combination with a static dorsal blocking or wrist orthosis for the initial 3 weeks.

RESULTS

Indications included sharp lacerations (n = 6), ragged lacerations (n = 2), staged flexor tendon reconstruction (n = 1), and type IV avulsion (n = 1). In 8 of the 10 cases that completed follow-up, the mean arc of proximal interphalangeal/distal interphalangeal active motion were as follows: sharp, 0° to 106°/0° to 75°; ragged, 0° to 90°/0° to 25°; reconstruction, 0° to 90°/10° to 45°; and avulsion, 0° to 95°/0° to 20°. Grip performance available for 6 of 10 cases was 62% to 108% of the dominant hand. There were no tendon ruptures, secondary surgeries, or proximal interphalangeal joint contractures.

CONCLUSION

Based on this small series, the RMF approach appears to be safe and effective. It can lead to similar mobility and functional recovery as other early active motion protocols, with certain practical advantages and without major complications. Further investigation with larger, multicenter, prospective, longitudinal cohorts and/or randomized clinical trials is necessary.

Mid-term Results of Two-Stage Tendon Reconstruction of Zone II Flexor Tendon Injuries

Background

Secondary repair of flexor tendon injuries remains a challenging procedure for hand surgeons. Usually, secondary reconstruction should be performed by a staged approach. Two-stage surgical reconstruction of the flexor tendons by the Hunter technique is the salvage option in case of a severely damaged fibro-osseous canal or neglected flexor tendon injury.

Aims

We report the results of staged flexor tendon reconstruction in 10 patients (10 fingers) with neglected or failed primary repair of flexor tendon injuries in zone II.

Materials and Methods

Between 2012-2016, patients who underwent two-stage tendon reconstruction due to flexor digitorum profundus (FDP) sectioning or tearing in zone II with destruction of flexor pulleys and extensive scarring in the flexor tendon bed were included in the study.

Results

Ten patients included to study with a mean follow-up of 34 months (range 12-70 months) and the results were assessed by clinical examination and questionnaire. According to the Strickland score, one (20%) of the results were excellent, five (50%) were good, two (20%) were fair and two (20%) were poor. After the second stage, good to excellent results were achieved in 60% of patients, one patient needed graft tenolysis. These results were similar to the subjective scores given by the patients, four of whom complained of functional problems in daily life at follow-up. There was no complication after the first stage. But after the second stage, there was one bowstringing and one adhesion that require tenolysis.

Conclusions

Hunter technique is still the reference procedure for the reconstruction of flexor tendons. The results of our study showed that two-stage tendon reconstruction which is applied in patients with tendon sheath disruption as a result of acute or delayed tendon injuries which are not possible for primary repair is reliable and satisfactory.

Out-of-sheath corticosteroid injections through the dorsal webspace for trigger finger and trigger thumb. A prospective cohort study

BACKGROUND AND OBJECTIVE

Steroid injections are effective in the treatment of trigger digits but the pain during the injection is an always-present accompanying effect. The aim of this study was to assess the effectiveness and perceived pain during an out-of-sheath corticosteroid injection through the dorsal webspace in the treatment of trigger digits.

MATERIAL AND METHOD

A total of 126 consecutive patients were included. A subcutaneous (out-of-sheath) corticosteroid injection was performed through the dorsal webspace in all digits. In cases where signs or symptoms persisted, a second injection was offered. Visual analog scale for pain during the injection, DASH questionnaire, success rate and complications were collected.

RESULTS

There were 86 women and 40 men with a mean age of 61 years. The mean visual analog scale for pain during the injection was 3.8. Twelve patients were lost to follow-up. The overall success was 68% and success after a single injection was 54%. The best result was achieved on the ring finger. Patients who were not previously operated on carpal tunnel syndrome responded better. No complications were noted.

CONCLUSIONS

The extra-sheath corticosteroid injection through the dorsal webspace is effective and safe. It seems to be less painful than the reported scores for the palmar midline technique although it should be assessed in a comparative study.

Tendon grafts with preserved muscle demonstrate similar biomechanical properties to tendon grafts stripped of muscular attachments: a biomechanical evaluation in a porcine model

Purpose

(1) To evaluate the biomechanical properties of a porcine flexor digitorum superficialis tendon graft with preserved muscle fibers and (2) to compare these results with the biomechanical properties of a porcine tendon graft after removal of associated muscle.

Methods

Eighty-two porcine forelegs were dissected and the flexor digitorum superficialis muscle tendons were harvested. The study comprised of two groups: Group 1 (G1), harvested tendon with preserved muscle tissue; and Group 2 (G2), harvested contralateral tendon with removal of all muscle tissue. Tests in both groups were conducted using an electro-mechanical material testing machine (Instron, model 23-5S, Instron Corp., Canton, MA, USA) with a 500 N force transducer. Yield load, stiffness, and maximum load were evaluated and compared between groups.

Results

The behavior of the autografts during the tests followed the same stretching, deformation, and failure patterns as those observed in human autografts subjected to axial strain. There were no significant differences in the comparison between groups for ultimate load to failure (p = 0.105), stiffness (p = 0.097), and energy (p = 0.761).

Conclusion

In this porcine model biomechanical study, using autograft tendon with preserved muscle showed no statistically significant differences for yield load, stiffness, or maximum load compared to autograft tendon without preserved muscle. The preservation of muscle on the autograft tendon did not compromise the mechanical properties of the autograft.

Level of evidence

Level III Controlled laboratory study

Flexor tendon injuries: Repair & Rehabilitation

Flexor tendon injuries are common and occur mostly by penetrating trauma. Suspected flexor tendon injuries require a thorough clinical assessment and often are not isolated injuries. A detailed understanding of flexor tendon anatomy and spatial relationships is essential, especially when repairing multi-tendon injuries. Principles of flexor tendon repair include a strong suture construct, minimising gap formation between tendon ends, preserving tendon blood supply and providing a smooth repair interface. Moreover, adequate exposure of the zone of injury using full-thickness skin flaps and preservation of neurovascular and pulley structures is essential. In this article an overview of contemporary management strategies is presented. Today's hand surgeons and therapists can choose from a variety of treatment options when managing these important and potentially life-changing injuries.

Delayed Rupture of All Digital Flexor Tendons Following Volar Locking Plate Fixation for Distal Radius Fracture: A Case Report

A 68-year-old man with a right distal radius fracture treated with volar locking plate fixation previously was unable to flex his right thumb and four fingers without experiencing any adverse event. The flexor pollicis longus was reconstructed with a tendon graft using the lengthened flexor digitorum superficialis. The flexor digitorum profundus (FDP) of the ring finger was reconstructed with a tendon graft using the palmaris longus. The FDP of the index and little fingers was reconstructed using the interconnected tendon graft to the ring finger. Postoperatively, active flexion of all fingers and thumb was restored; however, he was unable to grasp thin objects because of the absence of full finger flexion. This is the first case wherein all nine flexor tendons being involved after volar locking plate fixation for a distal radius end fracture. We demonstrated a reconstructive procedure for long-standing multiple flexor tendon rupture after volar locking plate fixation.

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.

Effects of wrist extension on median nerve and flexor tendon excursions in patients with carpal tunnel syndrome: a case control study

Background

Reduced gliding ability of the median nerve in the carpal tunnel has been observed in patients with carpal tunnel syndrome (CTS). The purpose of this study was to evaluate the gliding abilities of the median nerve and flexor tendon in patients with CTS and healthy participants in the neutral and 30° extended positions of the wrist and to compare the gliding between the finger flexion and extension phases.

Methods

Patients with CTS and healthy participants were consecutively recruited in a community hospital. All the subjects received the Boston CTS questionnaire, physical examinations, nerve conduction study (NCS), and ultrasonography of the upper extremities. Duplex Doppler ultrasonography was performed to evaluate the gliding abilities of the median nerve and flexor tendon when the subjects continuously moved their index finger in the neutral and 30° extension positions of the wrist.

Results

Forty-nine patients with CTS and 48 healthy volunteers were consecutively recruited. Significant differences in the Boston CTS questionnaire, physical examination and NCS results and the cross-sectional area of the median nerve were found between the patients and the healthy controls. The degree of median nerve gliding and the ratio of median nerve excursion to flexor tendon excursion in the CTS group were significantly lower than those in the healthy control group in both the neutral and 30° wrist extension positions. Significantly increased excursion of both the median nerve and flexor tendon from the neutral to the extended positions were found in the CTS group. The ratio of median nerve excursion to flexor tendon excursion was significantly higher in the finger flexion phase than in the extended phase in both groups, and this ratio had mild to moderate correlations with answers on the Boston CTS Questionnaire and with the NCS results.

Conclusions

Reduced excursion of the median nerve was found in the patients with CTS. The ratio of median nerve excursion to flexor tendon excursion was significantly lower in the patients with CTS than in the healthy volunteers. The median nerve excursion was increased while the wrist joint was extended to 30° in the patients with CTS. Wrist extension may be applied as part of the gliding exercise regimen for patients with CTS to improve median nerve mobilization.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04349-8.

Risk of septic spread during surgical management of digital flexor tendon sheath phlegmon: Exsanguination by mechanical compression versus simple elevation

This study aimed to demonstrate that there was no risk of extension of infection in performing mechanical exsanguination before inflating the tourniquet for surgical treatment of digital flexor tendon sheath phlegmon. The series comprised 96 patients, with a mean age of 47 years (range, 18-87 years) and 37 women. Group I included 47 patients in whom exsanguination was performed with a Velpeau band before inflating the pneumatic tourniquet at the root of the limb. In Group II, which included 49 patients, the tourniquet was inflated after simple elevation of the limb. Six patients underwent revision surgery for recurrence or osteoarticular complications: 4 (8.5%) in Group I and 2 (4.1%) in Group II, the difference between two groups being non-significant (p = 0.6378). In conclusion, mechanical exsanguination before inflating the tourniquet did not incur risk of complications in surgical management of digital flexor tendon sheath phlegmon.

Evaluation of the first annular pulley stretch effect under isometric contraction of the flexor tendon in healthy volunteers and trigger finger patients using ultrasonography

Background

Isometric exercises for a flexed finger have been reported to be effective for treating trigger finger as the flexor tendon widens the space under the first annular (A1) pulley towards the palmar destination during the exercise. This study aimed to evaluate the structural changes during the A1 pulley stretch in healthy volunteers and patients with trigger finger using ultrasonography.

Methods

We enrolled 25 male and 14 female patients (39 middle fingers). The thickness of the subcutaneous tissue (parameter a), A1 pulley (parameter b), and the flexor tendon (parameter c) and the distance between the dorsal surface of the flexor tendon and the palmar surface of the metacarpal head (parameter d) were measured using ultrasonography of the metacarpophalangeal joint of the middle finger flexed at 45° at rest (pattern A) and under isometric contraction of the flexor tendon against an extension force of the proximal interphalangeal joint (pattern B).

Results

The average differences between patterns A and B in the healthy volunteers were 0.29 mm (parameter a; P = 0.02), 0.017 mm (parameter b; P = 0.63), 0.16 (parameter c; P = 0.26), and 0.41 (parameter d; P = 0.004), and those in patients with trigger finger were 0.22 mm (parameter a; P = 0.23), 0.019 mm (parameter b; P = 0.85), 0.03 mm (parameter c; P = 0.82), and 0.78 mm (parameter d; P < 0.001). The distance between the dorsal side of the A1 pulley and the palmar surface of the metacarpal head was also significantly increased by 0.57 mm (8.2%) in healthy volunteers (P < 0.001) and 0.81 mm (11%) in patients with trigger finger (P < 0.001).

Conclusions

In this study, the space under the A1 pulley was expanded under isometric contraction of the flexor tendon. These findings support the effectiveness of pulley stretch exercises for the trigger finger condition.

Neglected flexor tendon injury for 10 years, un-usual finding and one stage repair without free tendon graft: Case report

Introduction

In delayed or neglected cases of flexor tendon injury, reconstruction of flexor digitorum profundus (FDP) is usually performed using free tendon graft due to the retraction of tendon ends and shortening of the tendon. Flexor digitorum superficialis (FDS), palmaris longus or plantaris tendons can be used as a free tendon graft [1–3].

Presentation of case

This is a case report of female patient 17 years old with neglected cut of her left Ring finger's FDP and FDS tendons zone II with suspected concomitant digital nerve injury, the injury was neglected for 10 years in the patient's non-dominant hand.

Discussion

Upon exploration unusual finding of spontaneous healing of the proximal stumps of FDS and FDP tendons raised the idea of doing the repair one stage without free graft by using pedicled intra-synovial graft from the sublimis tendon to reconstruct the FDP tendon.

The patient after 4 months follow-up and after completion of the physiotherapy program regained the ability to actively flex her finger to near full flexion with improved function and cosmesis.

Conclusion

Delayed flexor tendon reconstruction in neglected cases is still offering good results even after long periods of delay provided that the finger's joints are still supple and mobile.

•

In neglected cases of flexor tendon injury, reconstruction of FDP tendon is usually performed using free tendon graft.

•

The presence of two repair sites with free graft in between carries the risk of rupture or adhesion formation around the tendon graft.

•

In this case report we succeed in doing the repair one stage without free graft.We used pedicled intra-synovial graft from the sublimis tendon to reconstruct the FDP tendon.

A jersey finger diagnostic trap: Rupture of the flexor digitorum profundus tendon and the flexor digitorum superficialis tendon

Management of a 30-year-old man with a rarely described form of jersey finger: simultaneous rupture of the flexor digitorum profundus and flexor digitorum superficialis on the middle finger. Excision of the superficial tendon and anchoring of the flexor digitorum profundus tendon was performed. After 6 months of follow-up, the patient did not present any complaint and reported a complete return to his daily activities. Although very rare, these lesions could be easily detected upstream by ultrasound to avoid 'surprise' during surgical exploration and allow better operative planning.

Hot Topics in Hand and Wrist Surgery

The field of hand surgery continues to evolve in new and exciting directions. Advances in diagnosis and management for common complaints and complex injuries allow higher-level care, while still being cognizant of the cost of health care delivery. Indications and protocols for past paradigm shifts, such as volar locked plating for distal radial fractures, continue to be honed, and the outcomes seen for modern flexor tendon repairs are impressive. Open questions remain, but promising results for scaphoid nonunion surgery and peripheral nerve reconstruction with processed allograft will continue to shed light on these unsolved problems.

Comparative Accuracy of 1.5T MRI, 3T MRI, and Static Ultrasound in Diagnosis of Small Gaps in Repaired Flexor Tendons: A Cadaveric Study

PURPOSE

We hypothesized that magnetic resonance imaging (MRI) would more accurately diagnose small gaps (<6 mm) after flexor tendon repair than static ultrasound (US) and that suture artifact would negatively impair accuracy.

METHODS

A laceration of the flexor digitorum profundus was created in 160 fresh-frozen cadaveric digits and randomized to either an intact repair (0-mm gap) or repairs using a locked 4-strand suture repair with either 4-0 Prolene, Ethibond, or and gaps of 2, 4,or 6 mm; or no suture in which 2-, 4-, or 6-mm gaps were created without a suture crossing the repair site. We performed 1.5T and 3T MRI and static US studies; gap widths were estimated by radiologists blinded to suture presence and true gap widths.

RESULTS

The 1.5 and 3.0T MRI had a lower mean error than US for gap sizes 0 and 2 mm. All 3 modalities performed similarly for 4- and 6-mm gaps. Documentation of imaging artifact worsened error, and odds of seeing artifacts were 1.72 higher with MRI than with US. Suture did not worsen artifact nor impair accuracy for any of the 3 modalities. When no suture was used, all 3 modalities significantly overestimated the true gap.

CONCLUSIONS

MRI is most accurate for small gaps less than 4 mm. Although all modalities overestimated gap sizes in specimens with a 0-mm gap (intact tendon repair), mean overestimation (<2 mm) was not clinically relevant. Ultrasound overestimated 2-mm gaps (clinically intact repairs), whereas MRIs did not. We recommend MRI for evaluation of gaps after flexor tendon repair. The 1.5T has slightly better sensitivity and specificity for distinguishing clinically intact (gap < 3 mm) from clinically impaired (gap > 3 mm) repairs than the 3T.

CLINICAL RELEVANCE

Accurate diagnosis of intact repairs or small gaps (<3 mm) might prevent unnecessary exploration or allow modification of rehabilitation protocols. Diagnosis of clinically relevant gaps (3-6 mm) may allow for earlier revision surgery before significant tendon retraction and adhesions develop, possibly necessitating a staged reconstruction.

Ultrasonographic assessment in vivo of the excursion and tension of flexor digitorum profundus tendon on different rehabilitation protocols after tendon repair

STUDY DESIGN

Interpretive description study.

PURPOSE

In management of patients with flexion tendon injuries, passive, control active and active motion protocols were proposed after repair to minimize tendon adhesion. The purpose of this study was to compare the excursion distance and the tension of Flexor Digitorum Profundus (FDP) during simulated active and passive motion using ultrasonography techniques using normal subjects.

METHODS

Ultrasonographic assessment of FDP tendon of the middle finger was performed at the wrist level on 20 healthy college students using 3 types of treatment protocols: modified Kleinert protocol, modified Duran protocol, and active finger flexion protocol. The excursion distance was measured following the musculotendinous junction of FDP using the B mode ultrasound system. The elasticity of FDP tendon was measured using the shear wave elastography technique. The excursion distance and the elasticity value were compared among 3 protocols using one-way ANOVA analysis.

RESULTS

Twelve male and 8 female students with mean age of 22.6 ± 1.8 years were invited to join the study. The excursion distance of FDP was 21.82 ± 3.77 mm using the active finger flexion protocol, 8.59 ± 2.59 mm using the modified Duran protocol, and 12.26 ± 2.71 mm using the modified Kleinert protocol. The elasticity was significantly higher in extension position when compared to passive flexion positions, but found lower than active flexion position.

DISCUSSION

The active finger protocol was found to require strongest tension of the tendon and with longest excursion. There was similar tension generated using both passive motion protocols. The modified Duran protocol appeared to create less excursion upon movements than the modified Kleinert approach using the objective ultrasonic evaluation. It is suggested that if the surgical repair was strong and without any complications, the active flexion protocol might work best to regain tension excursion. However, if there are complex problems involved, then the Kleinert approach or Duran approach would be chosen.

Flexor tendon dysfunction due to a rare fracture of the proximal phalanx: A case report

Flexor tendon entrapment in fractures of the proximal phalanx is a rare occurrence. This complication has only been reported in association with displaced epiphyseal and diaphyseal fractures. Here we describe a case of an unusual proximal phalangeal fracture pattern with functional hindrance of the flexor mechanism. A 34-year-old man presented with an absent flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) function of the ring finger 4 weeks after an injury. X-Ray Examination revealed a bony fragment on the radial volar aspect of the proximal phalanx. USS revealed an intact FDS and FDP tendons. Excision of the bony fragment with tenolysis led to restoration of function.

Location of the Cut Flexor Tendons in the Palm Using Surface Anatomy: A Simple Guide for Minimal Incision Surgery

BACKGROUND

Hand Zone 2 flexor injuries are among the most important tendon lesions and its prognosis is poorer than the other hand zones. Limited incisions prevent multiple skin flaps. The present study aimed to determine the location of palmar flexor tendons using surface anatomical markers to provide a simple and easy guide for hand surgeons assisting them in minimal incisions.

METHODS

Patients with hand injuries in Zone 2 were taken to the operating room for surgery. The skin and subcutaneous tissue over the flexor tendons sheath were incised. After finding the flexor tendons in the palm, their exact position was located with a blue needle (23G) over the palm crease and marked relative to the finger borders.

RESULTS

Thirty-eight patients with the mean age of 27±3.6 years were operated. Totally, 57 fingers and 38 palms were dissected. The flexor tendons were located under the proximal and distal palm creases between two parallel lines extended from finger borders and mid-axial axis of the fingers. The average distance from finger print to distal palmar crease was 25, 32 and 24 mm for little, ring and long finger, respectively and 32 mm from index finger print to mid palmar crease.

CONCLUSION

The precise position of flexor tendons can be easily determined in the palm according to surface anatomical markers and plan for limited incisions.

Flexor tendon repair with amniotic membrane

PURPOSE

Flexor tendon adhesion to tissues is one of the most frequent complications reported after flexor tendon repair. The human amniotic membrane (HAM) was used to wrap the tendon repair site to decrease fibrotic response and tendon adhesion.

METHODS

A total of 19 patients with flexor tendon injuries were subjected to surgical repair. The repair site was wrapped with human amniotic membrane (HAM) in nine cases. The remaining ten cases served as controls as no HAM wrap was used. The clinical outcome was assessed by pain, range of motion, and pinch strength. The healing of repair was evaluated with high-frequency ultrasound; the biologic response was assessed with two inflammatory mediators, i.e., interleukin-6 and TGF-beta-1.

RESULTS

HAM wrap cases recorded less pain, higher total active range of motion, and better tendon glide on ultrasonography at follow-up (6-18 months). The levels of serum inflammatory biologic markers decreased in majority of HAM cases whereas they increased in controls at two to six weeks post-operatively. No infection/immune rejection phenomenon was seen in HAM wrap cases.

CONCLUSIONS

HAM wrap around the tendon repair site resulted in quicker function and qualitatively better tendon healing on ultrasound, with a decrease of the biologic response.

Dorsal web injection technique in the treatment of trigger finger and trigger thumb. Anatomical study

BACKGROUND AND OBJECTIVE

Corticosteroid injection is an effective treatment for trigger digits but the pain during the injection is an ever-present side effect. Since the palmar skin has a high density of sensitive receptors, injecting through dorsal skin could be less painful. Our aim was to assess whether a dorsal technique through the dorsal web is safe for extra-sheath injection of trigger fingers and thumb.

MATERIAL AND METHOD

This is an anatomical study in sixteen cadaveric hands. An injection through the dorsal web was performed on each digit. After careful resection of the palmar skin, the distance between the needle and the main anatomical structures was measured. The risk of major injury was considered high when the mean distance from the needle to the neurovascular bundle was below 1mm.

RESULTS

The mean distance from the needle to the neurovascular bundle was 1.77mm. Two neurovascular injuries in 112 injections were observed, one nerve and one artery. The safest digit was the thumb while the most dangerous was the index finger. At the ring finger, the technique was safer when it was carried out from the dorso-radial.

CONCLUSIONS

A subcutaneous injection near the flexor tendon sheath can be carried out through the dorsal web with a low, but present, risk of neurovascular injury. It could be useful for injection in the treatment of trigger finger and trigger thumb but it should be assessed in a clinical study.