Non-steroidal anti-inflammatory drugs (NSAIDs) for trigger finger.

BACKGROUND: Trigger finger is a common hand condition that occurs when movement of a finger flexor tendon through the first annular (A1) pulley is impaired by degeneration, inflammation, and swelling. This causes pain and restricted movement of the affected finger. Non-surgical treatment options include activity modification, oral and topical non-steroidal anti-inflammatory drugs (NSAIDs), splinting, and local injections with anti-inflammatory drugs. OBJECTIVES: To review the benefits and harms of non-steroidal anti-inflammatory drugs (NSAIDs) versus placebo, glucocorticoids, or different NSAIDs administered by the same route for trigger finger. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, CNKI (China National Knowledge Infrastructure), ProQuest Dissertations and Theses, www.ClinicalTrials.gov, and the WHO trials portal until 30 September 2020. We applied no language or publication status restrictions. SELECTION CRITERIA: We searched for randomised controlled trials (RCTs) and quasi-randomised trials of adult participants with trigger finger that compared NSAIDs administered topically, orally, or by injection versus placebo, glucocorticoid, or different NSAIDs administered by the same route. DATA COLLECTION AND ANALYSIS: Two or more review authors independently screened the reports, extracted data, and assessed risk of bias and GRADE certainty of evidence. The seven major outcomes were resolution of trigger finger symptoms, persistent moderate or severe symptoms, recurrence of symptoms, total active range of finger motion, residual pain, patient satisfaction, and adverse events. Treatment effects were reported as risk ratios (RRs) and mean differences (MDs) with 95% confidence intervals (CIs). MAIN RESULTS: Two RCTs conducted in an outpatient hospital setting were included (231 adult participants, mean age 58.6 years, 60% female, 95% to 100% moderate to severe disease). Both studies compared a single injection of a non-selective NSAID (12.5 mg diclofenac or 15.0 mg ketorolac) given at lower than normal doses with a single injection of a glucocorticoid (triamcinolone 20 mg or 5 mg), with maximum follow-up duration of 12 weeks or 24 weeks. In both studies, we detected risk of attrition and performance bias. One study also had risk of selection bias. The effects of treatment were sensitive to assumptions about missing outcomes. All seven outcomes were reported in one study, and five in the other. NSAID injection may offer little to no benefit over glucocorticoid injection, based on low- to very low-certainty evidence from two trials. Evidence was downgraded for bias and imprecision. There may be little to no difference between groups in resolution of symptoms at 12 to 24 weeks (34% with NSAIDs, 41% with glucocorticoids; absolute effect 7% lower, 95% confidence interval (CI) 16% lower to 5% higher; 2 studies, 231 participants; RR 0.83, 95% CI 0.62 to 1.11; low-certainty evidence). The rate of persistent moderate to severe symptoms may be higher at 12 to 24 weeks in the NSAIDs group (28%) compared to the glucocorticoid group (14%) (absolute effect 14% higher, 95% CI 2% to 33% higher; 2 studies, 231 participants; RR 2.03, 95% CI 1.19 to 3.46; low-certainty evidence). We are uncertain whether NSAIDs result in fewer recurrences at 12 to 24 weeks (1%) compared to glucocorticoid (21%) (absolute effect 20% lower, 95% CI 21% to 13% lower; 2 studies, 231 participants; RR 0.07, 95% CI 0.01 to 0.38; very low-certainty evidence). There may be little to no difference between groups in mean total active motion at 24 weeks (235 degrees with NSAIDs, 240 degrees with glucocorticoid) (absolute effect 5% lower, 95% CI 34.54% lower to 24.54% higher; 1 study, 99 participants; MD -5.00, 95% CI -34.54 to 24.54; low-certainty evidence). There may be little to no difference between groups in residual pain at 12 to 24 weeks (20% with NSAIDs, 24% with glucocorticoid) (absolute effect 4% lower, 95% CI 11% lower to 7% higher; 2 studies, 231 participants; RR 0.84, 95% CI 0.54 to 1.31; low-certainty evidence). There may be little to no difference between groups in participant-reported treatment success at 24 weeks (64% with NSAIDs, 68% with glucocorticoid) (absolute effect 4% lower, 95% CI 18% lower to 15% higher; 1 study, 121 participants; RR 0.95, 95% CI 0.74 to 1.23; low-certainty evidence). We are uncertain whether NSAID injection has an effect on adverse events at 12 to 24 weeks (1% with NSAIDs, 1% with glucocorticoid) (absolute effect 0% difference, 95% CI 2% lower to 3% higher; 2 studies, 231 participants; RR 2.00, 95% CI 0.19 to 21.42; very low-certainty evidence). AUTHORS' CONCLUSIONS: For adults with trigger finger, by 24 weeks' follow-up, results from two trials show that compared to glucocorticoid injection, NSAID injection offered little to no benefit in the treatment of trigger finger. Specifically, there was no difference in resolution, symptoms, recurrence, total active motion, residual pain, participant-reported treatment success, or adverse events.

Anatomical Study of the Medialis Pedis Flap and its clinical applications in Asian Singaporean Patients.

PURPOSE: The purpose of this study was to revisit the medial plantar artery's anatomy and study its distribution for raising the medialis pedis flap. Several investigators have reported their clinical experience with the use of this flap for reconstruction of soft tissue defects of the hand. However, many have reported difficulty raising the flap due to variations in its arterial anatomy and the confusion that exists with respect to the nomenclature in our literature. METHODS: This study was divided into 2 parts: an anatomic study and clinical application. In the anatomic study, 12 cadaveric feet specimens from 6 patients were injected with latex and barium-gelatin injections and the medial branch of the deep division of the medial plantar artery distribution was studied. We then described the use of a medialis pedis flap in four clinical cases to cover defects of the digits. RESULTS: The anatomic study revealed that the average pedicle length of the deep division of the medial plantar artery was 1.94cm. In the four illustrative clinical cases where the flap was used, the average flap size was 4.5 × 3.75cm. Donor sites were either closed primarily or with skin grafts. The vessels used for this flap were the medial branch of the deep division of the medial plantar artery and venae commitantes, or subcutaneous veins which provided the superficial drainage. All flaps were successful without any significant complications. The study is novel in that it describes the anatomic variability of length of the medial branch of the deep division of the medial plantar artery that exits in nature. CONCLUSIONS: This paper describes the medial branch of the deep division of the medial plantar artery and the anatomic variations that exist in the raising of the medialis pedis flap. We have shown how a medialis pedis flap is an ideal option for reconstructing soft tissue defects of the hand because of its texture, bulkiness and pliability in the context of like for like reconstruction.

Biomechanical comparison of vertical suture techniques for repairing radial meniscus tear.

PURPOSE: The aim of this study was to (1) develop suture techniques in repairing radial meniscal tear; (2) to compare the biomechanical properties of the proposed repair techniques with the conventional double horizontal technique. METHODS: Thirty-six fresh-frozen porcine medial menisci were randomly assigned into four groups and a complete tear was made at the midline of each meniscus. The menisci were subsequently repaired using four different repair techniques: double vertical (DV), double vertical cross (DVX), hybrid composing one vertical and one horizontal stitch, and conventional double horizontal (DH) suture technique with suturing parallel to the tibia plateau. The conventional double horizontal group was the control. The repaired menisci were subjected to cyclic loading followed by the load to failure testing. Gap formation and strength were measured, stiffness was calculated, and mode of failure was recorded. RESULTS: Group differences in gap formation were not statistically significant at 100 cycles (p = .42), 300 cycles (p = .68), and 500 cycles (p = .70). A trend was found toward higher load to failure in DVX (276.8 N, p < .001), DV (241.5 N, p < .001), and Hybrid (237.6 N, p < .001) compared with DH (148.5 N). Stiffness was also higher in DVX (60.7 N/mm, p < .001), DV (55.3 N/mm, p < .01), and Hybrid (52.1 N/mm, p < .01), than DH group (30.5 N/mm). Tissue failure was the only failure mode observed in all specimens. CONCLUSION: Our two proposed vertical suture techniques, as well as the double vertical technique, had superior biomechanical properties than the conventional technique as demonstrated by higher stiffness and higher strength.

Positive Ulnar Fovea Sign - Audit of Patient Outcomes Following Nonsurgical and Surgical Management.

Background: Patients with ulnar-sided wrist pain and positive ulnar fovea sign are usually treated nonsurgically before surgical options are considered. However, the outcomes of nonsurgical management are unknown. Many of these patients also have unstable distal radioulnar joint, but there has been no comparison between the outcomes of these patients with stable and unstable distal radioulnar joint. The objectives of this study are to (1) determine the outcomes of nonsurgical and surgical treatment of patients with positive ulnar fovea sign, and (2) compare the outcomes of patients with stable and unstable distal radioulnar joint. Methods: A retrospective analysis of the outcomes of patients with ulnar sided wrist pain and positive fovea sign was performed from March 2009 to December 2014. Outcomes were measured based on patient-reported pain improvement, grip strength and range of motion of the affected wrist before and after treatment. A total of 100 wrists in 98 patients were reviewed. Results: 54% of wrists managed nonsurgically experienced pain improvement. 83% of wrists managed surgically experienced pain improvement. The mean grip strength increased by 2.8 kg and 2.7 kg, while the range of motion decreased by 14° and 5° after nonsurgical and surgical treatment respectively. When comparing patients with stable and unstable distal radioulnar joint, there were statistically more wrists with unstable distal radioulnar joint that experienced pain improvement after treatment. Conclusions: The study showed that there is a role for nonsurgical treatment for wrists with positive ulnar fovea sign with more than half of the patients experiencing pain improvement. We also found that positive ulnar fovea sign patients with unstable distal radioulnar joint had better pain outcomes compared to those with stable distal radioulnar joint.

Asymmetric 6-Strand Flexor Tendon Repair - Biomechanical Analysis Using Barbed Suture.

Background: This study investigates the biomechanical performance of the Asymmetric flexor tendon repair technique using barbed suture. The Asymmetric repair technique using monofilament nylon suture was previously reported to have a higher tensile strength than the modified Lim-Tsai repair technique, but its repair stiffness and load to gap force were significantly lower. There is hence an unmet need to improve this technique and the substitution of nylon suture with barbed sutures may be the solution. Methods: Two groups consisting of 10 porcine tendons each were repaired with the six-strand Asymmetric repair technique using V-Loc® 3-0 and Supramid® 4-0 respectively. The repairs were subjected to a mechanical tester for static testing. The ultimate tensile strength, load to 2 mm gap force, repair stiffness, time taken to complete a repair and failure mechanism of the repairs were recorded and analyzed. Results: All the repairs using V-Loc® 3-0 sutures had significantly higher median values of ultimate tensile strength (64.1 N; 56.9 N), load to 2 mm gap force (39.2 N; 19.7 N), repair stiffness (6.4 N/mm; 4.7 N/mm) and time taken to complete a repair (9.4 mins; 7.7 mins). All the repairs using V-Loc® sutures failed by suture breakage while 80% of repairs using Supramid® sutures failed by suture pullout. Conclusions: The use of the barbed sutures in the Asymmetric repair technique, whilst more time consuming, has shown promising improvement to its biomechanical performance (i.e. better ultimate tensile strength, stiffness and resistance to gap formation).

Biomechanical evaluation of peripheral nerves after crush injuries.

BACKGROUND: Crush injury of nerves is a common condition but the biomechanical integrity of the human peripheral nerve after crushing is unknown. This study aims to investigate the impact of crush injury on human digital nerves based on different compressive forces. MATERIALS AND METHODS: Twenty digital nerves were harvested from three fresh-frozen cadaver hands. The original diameters of proximal, middle and distal end of nerve segment were measured. The midst of each digital nerve was compressed by a customized mechanical system, at 1N, 3N and 5N for 30sec. The diameters were measured again within 1 minute after the nerve crush test was performed. The digital nerve was then subjected to biomechanical test to measure its ultimate tensile strength, stiffness, maximum stress and strain. Deformity of digital nerve was computed based on the diameter of middle nerve segment before and after crush test. RESULTS: No significant difference was found in between groups for ultimate tensile strength (p=0.598), stiffness (p=0.593), maximum stress (p=0.7) and strain (p=0.666). The deformity of nerves under the compression of 1N, 3N and 5N was computed at 72.1%, 54.2% and 45.9%. The effect of compression on the deformity of nerves was statistically significant (p<0.001). CONCLUSIONS: It was found that the compressive forces have no impact on the biomechanical integrity of peripheral nerves but the deformity of nerves could be severely caused by low compressive force. It is suggested that the management of nerve crush injury shall be taken immediately and focus on neurophysiological function and degeneration of nerves for a crush with low compressive force and short duration.

Computational Simulation of Synovial Fluid Kinematics of the Scapholunate Joint.

Background: The interaction between wrist kinematics and synovial fluid pressure has yet to be studied. To our knowledge, this is the first study to determine the effect of scapholunate joint kinematics on synovial fluid pressure change using finite volume method. Methods: The carpal bones of a cadaveric hand were obtained from Computed Tomography (CT) scans. CT images of the carpal bones were segmented and reconstructed into 3D model. The 3D synovial fluid model between the scaphoid and lunate was constructed and then used for computational simulations. The kinematics data of scapholunate joint obtained from radioulnar deviation of the wrist was investigated. Results: It was found that the pressure in synovial fluid varied from -1.68 to 2.64 Pa with maximum pressure located at the scaphoid-fluid interface during the radial deviation. For ulnar deviation, the pressure increased gradually from the scaphoid-fluid interface towards the lunate-fluid interface (-1.37 to 0.37 Pa). Conclusions: This new computational model provides a basis for the study of pathomechanics of ligament injury with the inclusion of synovial fluid.

Clinical Outcomes of Zone 2 Flexor Tendon Repairs Using the Modified Lim/Tsai Technique.

BACKGROUND: The single looped suture modified Lim/Tsai technique is widely used for flexor tendon repairs. It has been shown to possess better biomechanical properties and require less repair time per tendon as compared to the double looped suture original Lim/Tsai technique. However, there is no clinical data on the modified technique. METHODS: The retrospective study included zone 2 flexor tendon repairs made using the modified Lim/Tsai technique from January 2008 to December 2014. Clinical outcome was assessed using the revised Strickland and Glogovac criteria, which categorises repairs based on the total active motion of the repaired digit. RESULTS: Sixty-two patients with 74 digits were included. The overall mean total active motion was 122°. The overall satisfactory outcome of the modified Lim/Tsai technique was 81.1%. The rupture rate of the modified Lim/Tsai technique was 2.7%. Using multivariate linear regression model, we found that outcomes were negatively influenced by subzone 2C and crush/saw injuries, but not by concomitant neurovascular injuries or post-operative follow-up duration. CONCLUSIONS: Based on this retrospective study of patients with zone 2 flexor tendon injuries, the clinical outcomes of modified and original Lim/Tsai techniques are comparable. As such, there is no clinical evidence favouring one over the other.

Hand Assessment for Elderly People in the Community.

BACKGROUND: Hand conditions are common in elderly persons. PURPOSE: To assess the prevalence of common hand conditions in elderly persons in a community setting, specifically osteoarthritis of the hand, trigger finger, and carpal tunnel syndrome. METHODS: The elderly persons were recruited from community groups for elderly persons. Data collection included participants' demographic and clinical data; quick disability, arm, shoulder, and hand (QuickDASH) questionnaire; and presence of hand conditions. RESULTS: Of the 55 elderly persons recruited, almost a third of them presented with a hand condition (n = 17, 30.8%). Hand conditions were more common in females (39% in females, 7% in males; χ = 4.97, p = .04). Quick-DASH scores were higher in those with hand conditions, indicating lower levels of function (greater disability) (t =-4.61, p = .002). CONCLUSIONS: Most elderly persons did not seek medical attention for their hand condition until the late stages. Nurses can play an important role in providing community hand assessment, education on hand symptoms, information about available treatment, and adaptive approaches to maximize functioning.

A review of cyclic testing protocols for flexor tendon repairs.

BACKGROUND: Cyclic testing of flexor tendons aims to simulate post-operative rehabilitation and is more rigorous than static testing. However, there are many different protocols, making comparisons difficult. We reviewed these protocols and suggested two protocols that simulate passive and active mobilization. METHODS: Literature search was performed to look for cyclic testing protocols used to evaluate flexor tendon repairs. Preload, cyclic load, number of cycles, frequency and displacement rate were categorised. FINDINGS: Thirty-five studies with 42 different protocols were included. Thirty-one protocols were single-staged, while 11 protocols were multiple-staged. Twenty-nine out of 42 protocols used preload, ranging from 0.2 to 5 N. Preload of 2 N was used in most protocols. The cyclic load that was most commonly used was between 11 and 20 N. Cyclic load with increment of 10 N after each stage was used in multiple-staged protocols. The most commonly used number of cycles was between 100 and 1000. Most protocols used a frequency of <1 Hz and displacement rate between 0 and 20 mm/min. INTERPRETATION: We propose two single-staged protocols as examples. Protocol 1: cyclic load of 15 N to simulate passive mobilization with preload of 2 N and 2000 cycles at frequency of 0.2 Hz.; Protocol 2: cyclic load of 38 N to simulate active mobilization, with the same preload, number of cycles, and frequency as above. This review consolidates the current understanding of cyclic testing and may help clinicians and investigators improve the design of flexor tendon repairs, allow for comparisons of different repairs using the same protocol, and evaluate flexor tendon repairs more rigorously before clinical applications.

Flexor Tendon Injuries and Repairs: A Single Centre Experience.

BACKGROUND: Although flexor tendon injuries cause significant morbidities and socio-economic implications, there have been limited data on patient demographics, injury characteristics and surgical details. The aim of this study is to describe our experience in flexor tendon injuries and repairs. METHODS: We performed a retrospective study of all digital flexor tendon injuries that were repaired from January 2011 to December 2014. The collected data included patient demographics, injury characteristics and surgical details. RESULTS: A total of 214 patients, 308 digits with 446 flexor tendon repairs were identified. We found that males, non-residents, and 20-29 age group were most prone to flexor tendon injuries. Cleaners, labourers and related occupations were the most vulnerable. The mechanism of injury was usually work-related and mostly caused by glass. Most injuries involve both flexor digitorum profundus and flexor digitorum superficialis tendons. Concomitant digital nerve and vessel injuries were common. Most patients suffered zone 2 laceration of a single digit of the non-dominant hand. Most patients underwent procedures that lasted 1 to 2 hours, including multiple flexor tendon repairs, microsurgical repairs and other interventions. CONCLUSIONS: This study is the largest study on patient demographics, injury characteristics and surgical details on flexor tendon injuries and repairs. It could be used to plan resources and policies for the management and prevention of flexor tendon injuries.

An Exploratory Study Using Semi-Tabular Plate in Zone II Flexor Tendon Repair.

BACKGROUND: This study evaluated the feasibility of using a low-profile titanium (Ti) plate implant, also known as the Ti-button, for Zone II flexor tendon repair. We hypothesize that the use of the Ti-button can distribute the tensile force on the digital flexor tendons to achieve better biomechanical performance. METHODS: Twenty lacerated porcine flexor tendons were randomly divided into two groups and repaired using Ti-button or 6-strand modified Lim-Tsai technique. Ultimate tensile strength, load to 2 mm gap force, and mode of failure were recorded during a single cycle loading test. We also harvested twelve fingers with lacerated flexor digitorum profundus tendons from six fresh-frozen cadaver hands and repaired the tendons using either Ti-button method or modified Lim-Tsai technique. A custom-made bio-friction measurement jig was used to measure the gliding resistance and coefficient of friction of the tendon sheath interface at the A2 pulley. RESULTS: The ultimate tensile strength, load to 2 mm gap force, stiffness, and gliding resistance of the Ti-button repairs were 101.5 N, 25.7 N, 7.8 N/mm, and 2.2 N respectively. Ti-button repairs had significantly higher ultimate tensile strength and stiffness than the modified Lim-Tsai repair. However, Ti-button also increased the gliding resistance and coefficient of friction but there was no significant difference between the two repair techniques. CONCLUSIONS: Ti-button repair displayed comparable mechanical properties to the traditional repair in terms of 2-mm gap formation and gliding resistance, but with a stronger repair construct. Thus, this deepened our interest to further investigate the potential of using Ti-button implant in Zone II flexor tendon repair by studying both the mechanical and biochemical (tendon healing) properties in more in-depth.

The Effect of Suture Materials on the Biomechanical Performance of Different Flexor Tendon Repairs and the Concept of Construct Efficiency.

BACKGROUND: To propose a new term ('construct efficiency') for the evaluation of multi strands flexor tendon repairs using different suture materials. METHODS: A total of twenty specimens from 4-0 braided polyblend sutures (FiberLoop/FiberWire; Arthrex, Naples, FL) and 4-0 nylon sutures (Supramid Extra II; S. Jackson, Inc., Alexandria, VA) were subjected to tensile testing using Pneumatic Cord-and-Yarn Grips (Instron Corp., Canton MA, USA). The ultimate tensile strengths of the suture materials were measured. The expected repair strengths and construct efficiencies were computed based on the experimental results and from available literature on actual repair strengths of the 4-strand Becker, Cruciate repairs and 6-strand Tang, modified Lim-Tsai repairs. RESULTS: The ultimate tensile strength of nylon suture was 15.4 ± 0.6N, lower than that of braided polyblend suture (45.3 ± 2.3N) with a difference of 194%. The construct efficiency of multi strand repairs varied with respect to different repair techniques and suture materials. It was found that the Becker repairs using FiberWire had the highest construct efficiency (55.7%) followed by the modified Lim-Tsai using Supramid (50.9%), Tang repair using Supramid (49.8%), Cruciate repair using Fiberwire (49.1%), and modified Lim-Tsai repair using FiberLoop (33.5%). CONCLUSIONS: The construct efficiency is more accurate in showing that, in terms of biomechanical strength, the use of FiberWire for the 4-strand Becker and Cruciate repair is more efficient than that of using FiberLoop for 6-strand modified Lim-Tsai repair.

Biomechanical comparison of modified Lim/Tsai tendon repairs with intra- and extra-tendinous knots.

We compared the Lim/Tsai tendon repair technique using an extra-tendinous knot with modification using an intra-tendinous knot. The ultimate tensile strength, load to 2 mm gap force, stiffness, mode of failure, location of failure, and time taken to repair each tendon were recorded during a single cycle loading test in 20 tendons with each repair method. We found that the ultimate tensile strength and 2 mm gap force of the modified Lim/Tsai repair with an extra-tendinous knot (56 SD 5 N and 14 SD 2 N, respectively) were statistically significantly higher than that of the modified Lim/Tsai repair with intra-tendinous knot (51 SD 7 N and 11 SD 2 N, respectively). We conclude that the modified Lim/Tsai repair with extra-tendinous knot is stronger, despite having the same number of core strands.

A cyclic testing comparison of two flexor tendon repairs: asymmetric and modified Lim-Tsai techniques.

This study compared the biomechanical performance of a novel 6-strand asymmetric flexor tendon repair with the modified Lim-Tsai technique using cyclic testing. Two groups of ten porcine tendons each were repaired and tested. Gap formation at every 100 cycles was measured. Survival was defined as maximum gap formation below 2 mm. All the repairs survived Stage I. With increased cyclic load in Stage II, the mean gap formation of modified Lim-Tsai repairs exceeded 2 mm at the 600th cycle and reached 4.2 mm (SD 1.93) at the end of Stage II, resulting in 0% survival. The mean gap formation of asymmetric repairs reached 2.0 mm (SD 1.43) at the 800th cycle and was 2.4 mm (SD 1.52) at the end of Stage II, with 60% survival. The asymmetric repair has better biomechanical performance under cyclic testing as compared with the modified Lim-Tsai repair.

A randomized controlled trial comparing ketorolac and triamcinolone injections in adults with trigger digits.

We assessed the efficacy of ketorolac trometamol injections compared with triamcinolone acetonide injections in trigger digits. Patients with trigger digits were randomized to receive either ketorolac or triamcinolone. They were followed up at 3, 6, 12 and 24 weeks, and monitored for resolution of triggering, pain and total active motion. One hundred and twenty-one patients with single trigger digits were recruited (59 ketorolac, 62 triamcinolone). At 6 weeks, 54% of patients in the triamcinolone group had complete resolution of trigger, whereas no patients in the ketorolac group had resolution. At 12 weeks, 58% of patients in the triamcinolone group had complete resolution of trigger compared with 6.7% in the ketorolac group. At 24 weeks, both groups had comparable rates of resolution at 26% and 25%, respectively. Patients in the triamcinolone group had significantly better resolution of pain at 3, 6 and 12 weeks. But at 24 weeks, there was no significant difference in pain between both groups. Significantly less flexion deformity was reported at 3 weeks and 6 weeks in the triamcinolone group. In the short term, ketorolac was less effective in relieving symptoms of trigger digit than triamcinolone. Level of evidence: I.

A Biomechanical Study of a Novel Asymmetric 6-Strand Flexor Tendon Repair Using Porcine Tendons.

BACKGROUND: This study evaluated the biomechanical performance of a novel asymmetric 6-strand flexor tendon repair technique without locking loops. METHODS: Twenty porcine flexor tendons were equally repaired by using the asymmetric technique and compared with the modified Lim-Tsai repair technique. The ultimate tensile strength, load to 1-mm gap force, stiffness, and mechanism of failure were measured. RESULTS: The asymmetric repair technique had significantly higher tensile strength (63.3 ± 3.7 N) than the modified Lim-Tsai repairs (46.7 ± 8.3 N). CONCLUSIONS: A novel flexor tendon repair technique with improved biomechanical performance may be available for use in flexor tendon repairs.

Normative data on functional grip strength of elderly in Singapore.

STUDY DESIGN: Cross-sectional study for clinical measurement. INTRODUCTION: Most daily tasks require individuals to exert grip strength with torque, which can be challenging for elderly as their strength diminishes with age. We postulate that to assess the functional capacity of an individual, it is important to evaluate the functional grip strength instead of the maximal static grip strength. PURPOSE OF THE STUDY: The objective of this cross-sectional study is to establish normative data for the functional grip strength of elderly aged 60 years and older in the Singapore population. METHODS: In this study, 233 healthy subjects aged 60 years and older were recruited. Using a custom-made hand strength measurement device, the following measurements were recorded: grip strength at neutral position, grip strength with resistive pronation torque, and grip strength with resistive supination torque. RESULTS: Grip strengths measured for both genders decreased by 13% and 16% for males and females respectively, when pronation torque was exerted, and with supination torque, the strength decreased by 18% and 17% for males and females respectively. CONCLUSION: Normative data for the elderly population in Singapore had been established. The findings from this study can complement the existing ergonomic hand data in designing better assistive tools to improve the independent living of elderly. LEVEL OF EVIDENCE: NA.

Cyclic Testing of the 6-Strand Tang and Modified Lim-Tsai Flexor Tendon Repair Techniques.

PURPOSE: In this study, we compared the Tang repair technique with the 6-strand modified Lim-Tsai repair technique under cyclic testing conditions. METHODS: Twenty fresh-frozen porcine flexor tendons were randomized into 2 groups for repair with either the modified Lim-Tsai or the Tang technique using Supramid 4-0 core sutures and Ethilon 6-0 epitendinous running suture. The repaired tendons were subjected to 2 stage cyclic loading. The survival rate and gap formation at the repair site were recorded. RESULTS: Tendons repaired by the Tang technique achieved an 80% survival rate. None of the modified Lim-Tsai repairs survived. The mean gap formed at the end of 1000 cycles was 1.09 mm in the Tang repairs compared with 4.15 mm in the modified Lim-Tsai repairs. CONCLUSIONS: The Tang repair is biomechanically stronger than the modified Lim-Tsai repair under cyclic loading. CLINICAL RELEVANCE: The Tang repair technique may exhibit a higher tolerance for active mobilization after surgery with less propensity for gap formation.