The Journal of Hand Surgery (Asian-Pacific Volume)

Electrical stimulation has been integrated in recent decades into rehabilitation protocols following neuromuscular injuries. Existing literature supports the utilisation of prolonged or continuous stimulation generated by implantable or transcutaneous devices for chronic pain subsidence and muscle trophism maintenance, which improve outcomes following microsurgical interventions. Newer uses include brief electrical stimulation for peripheral nerve injury. Brief electrical stimulation has shown promise in expediting regeneration of both torn and crushed nerve axons in the murine model and has been incorporated into a limited number of clinical studies. Augmentation of the natural response of an injured peripheral nerve by electrical stimulation has the potential to accelerate regeneration, presumably leading to improved function and clinical outcomes. We review the existing literature on intraoperative utilisation of electrical stimulation to enhance regeneration, such as neural mechanisms of action and their microscopic effect in animal models, as well as results from initial human studies.

Level of Evidence: Level V (Therapeutic)

Forearm non-union poses a challenge in orthopaedic surgery due to its intricate anatomy and functional significance. This review provides a comprehensive overview of the assessment, diagnosis and management of forearm non-union. Initial evaluation involves a meticulous history, physical examination and imaging studies to identify factors contributing to non-union, including infection. Surgical approaches are discussed, with emphasis on restoring biomechanical stability and promoting bone healing. Treatment options range from autografts to allografts, with considerations for vascularised bone transfers in complex cases. Decision-making strategies are outlined, considering patient-specific factors and individualised treatment plans. Special considerations for specific types of forearm non-unions are addressed, along with postoperative care protocols to optimise healing and functional outcomes. Overall, this review aims to provide clinicians with a comprehensive understanding of forearm non-union management based on current evidence and clinical practice.

Level of Evidence: Level V (Therapeutic)

Background: Radial head dislocation in patients with multiple hereditary exostoses (MHE) is associated with loss of function and cosmetic problems. The treatment of the deformity with radial head dislocation is difficult and the timing of surgical intervention is important. The aim of this study was to evaluate the factors predictive of radial head dislocation in patients with MHE.

Methods: Patients diagnosed with forearm deformity due to MHE between 1995 and 2021 were retrospectively evaluated. Radiographic parameters including radial bow (RB), ulnar bow (UB), total radial bow (TRB), total ulnar bow (TUB), percent ulnar length (PUL), ulnar shortening (US), radial articular angle (RAA), modified Masada classification and irregularity of proximal radioulnar joint (PRUJ) of the dislocated group (group D), that is subluxation or dislocation of the radial head, and the located group (group L) were compared.

Results: A total of 18 patients and 25 limbs (5 girls and 13 boys) with a mean age of 10.5 years were included. There were significant differences in TUB (22.8° ± 5.6° vs. 10.7° ± 6.5°), PUL (97.5% ± 5.5% vs. 108.2% ± 7.7%) between group D and group L (p < 0.05). Moreover, irregularity of PRUJ on radiographs was more in group D (p < 0.05).

Conclusions: It is possible that appropriate radiographic assessment in relation to radial head dislocation may prevent delayed surgical treatment of forearm deformities in MHE.

Level of Evidence: Level IV (Diagnostic)

Background: Accurate implant placement in the optimal position is important to obtain favourable clinical outcomes and prevent complications in total joint arthroplasty. We aimed to assess the accuracy of implant placement based on three-dimensional (3D) preoperative planning for unlinked total elbow arthroplasty (TEA) and to clarify the effect of implant placement on clinical outcomes.

Methods: This study included 20 patients (22 elbows, 17 with rheumatoid arthritis and 5 with osteoarthritis, with a mean follow-up period of 47 months) who underwent TEA with an unlinked-type implant after computed tomography (CT)-based 3D preoperative planning. Implant placement was planned preoperatively and several parameters were set to reflect it intraoperatively. TEA was performed based on the plan, and postoperative CT was conducted to evaluate differences in implant placement by comparing the preoperative plan and postoperative implant placement. Furthermore, we evaluated the relationship between implant placement differences and postoperative clinical outcomes, including range of motion, Visual Analogue Scale, Mayo Elbow Performance Score 1 year after surgery and complications at the last follow-up.

Results: The mean absolute translation was within 2 mm, the mean absolute tilt was within 4°, the mean absolute rotation of the humeral component was within 4° and the mean absolute rotation of the ulnar component was 10.2° ± 6.8°. In the ulnar components, 15/22 (68%) cases were externally rotated, and the mean external rotation was 7.1° ± 10.2°. We defined the absolute ulnar component’s rotational difference of more than 10° as a ‘malrotation’ group (n = 8) and 10° or less as a ‘control’ group (n = 14). We compared the clinical outcomes between both groups, however, no significant differences were observed in clinical outcomes and complications.

Conclusions: We observed notable malrotation in the postoperative positioning of the ulnar component. Intraoperative support devices may be necessary to accurately reproduce the preoperative plan in the surgical field.

Level of Evidence: Level IV (Therapeutic)

Background: Clinical quality measures exist for non-operative management of carpal tunnel syndrome (CTS). Factors predicting adherence are unclear.

Methods: A retrospective cohort study of patients with chronic CTS using MarketScan Research Database (2015–2020) was conducted. Six logistic regression models were designed to study adherence to quality measures within 1 year after diagnosis.

Results: Of 782,717 patients identified, 514,073 (65.7%) were female with an average (SD) age of 51.4 (13.4) years. Only 88 patients (0.01%) met all quality measures. Greatest compliance observed with receipt of nerve conduction study (NCS; 283,959 [36.3%]), no prescription of medications (336,297 [43.0%]) and no laser therapy (772,979 [98.8%]); 294,305 patients (37.6%) received hand surgeon referral. Hand surgeon referral predicted higher likelihood of NCS and splinting (OR, 1.83; 95% CI: 1.81–1.84; OR, 2.53; 95% CI: 2.50–2.56) and medication over-prescription (OR, 1.05; 95% CI: 1.00–1.10). Females were more likely to be referred to a hand surgeon and be referred for splinting (OR 1.02; 95% CI: 1.01–1.03; OR 1.19; 95% CI: 1.18–1.21) but less likely to have no prescriptions or avoid laser therapy (OR 0.85, 95% CI: 0.84–0.85; OR 0.82, 95% CI: 0.79–0.86). Medicare recipients adhered less to quality measures compared to patients with fee-for-service insurance. As comorbidities increased, patients were less likely to receive hand surgeon referral and carpal tunnel release.

Conclusions: Findings suggest that hand surgery referrals increased adherence to quality measures. Females, Medicare recipients and multimorbid patients should be targeted for improved care. Future quality care efforts should incentivise adherence for Medicare beneficiaries and improve guideline recognition amongst physicians.

Level of Evidence: Level III (Therapeutic)

Background: The aim of this study was to evaluate the chicken femur as a laboratory model for the human metacarpal by comparing the bone microarchitecture and mechanical properties of chicken femurs to human cadaveric metacarpals.

Methods: Sixteen fresh chicken femora and 20 fresh frozen cadaveric human metacarpals were imaged using a micro computed tomography scanner. The bones were then mechanically tested using four-point-bending and torsional testing.

Results: There were no significant differences in macroscopic features between chicken femora and human metacarpals, including overall length, external radius, internal radius, cortical width and cross-sectional area of the diaphyseal cortex (p > 0.05). There were no significant differences in the trabecular number and spacing in the distal metaphysis of both groups (p > 0.05). The diaphysis and proximal metaphysis did not share any microarchitectural similarities. Four-point bending tests resulted in significantly higher yield forces, ultimate force, failure points and stiffness in human metacarpals (p < 0.05). Torsion tests resulted in significant higher ultimate torque and torsional rigidity in human metacarpals (p < 0.05).

Conclusions: The chicken femur has structural and biomechanical differences to the fresh frozen human metacarpal despite the similarity in their macroscopic features.

Background: High-energy distal radius fractures have not been as well studied as the more common osteoporotic fractures. Differences between these two groups of fractures have implications on the prevention and clinical management of such injuries.

Methods: A retrospective review was conducted of all patients in our institution who presented with distal radius fractures within the period of a year. Demographic data, injury mechanism, fracture classification, associated injuries and work-related status were obtained and analysed.

Results: High energy fractures made up 27.1% of the cases. Falls from height were the most common cause, followed by motor vehicle accidents. These high-energy fractures were more commonly seen in males, younger patients (average age 41 vs. 61 years), and in workplace accidents. These injuries were also more likely to be bilateral and associated with an additional ipsilateral upper extremity injury. The high-energy group was also more likely to have an AO type B fracture.

Conclusions: A substantial proportion of distal radius fractures seen in our population are high-energy injuries. Their contrasting patient and injury profiles suggest that they should be considered separately from osteoporotic fractures.

Level of Evidence: Level IV (Therapeutic)

Background: This retrospective study compares the outcomes of trapeziectomy and Weilby suspensionplasty procedure versus implant arthroplasty using the TOUCH^® prosthesis for basilar thumb arthritis in an Asian population.

Methods: A total of 15 consecutive thumbs in 13 patients were included in this study. Six patients (2 male, 4 female, mean age of 62 years old) underwent trapeziectomy and Weilby suspensionplasty procedure. Seven patients (4 male, 3 female, mean age 63 years old) underwent implant CMCJ arthroplasty using the TOUCH^® prosthesis. Data collected include demographics, severity of arthritis on plain radiographs of the thumb basilar joint, length of follow-up, pre- and postoperative pain levels, Kapandji thumb opposition score, grip and pinch strength and the time taken to return to work.

Results: Patients in the trapeziectomy and Weilby suspensionplasty group had a mean follow-up of 4.5 months, while those in the TOUCH^® implant arthroplasty group had a mean follow-up of 14 months. TOUCH^® implant arthroplasty patients showed significantly higher grip strengths at 3 months post-surgery and a shorter return to work. There were no differences in pinch strength at 3 months, pinch or grip strength at 6 months or pain scores. Complications included prolonged scar hypersensitivity in two patients who underwent the Weilby suspensionplasty and a dislocated TOUCH^® implant cup in one patient.

Conclusions: Our study suggests that in the short term, CMCJ implant arthroplasty with the TOUCH^® prosthesis produces results comparable to trapeziectomy and Weilby suspensionplasty.

Level of Evidence: Level III (Therapeutic)

Background: Dual mobility total joint arthroplasty is gaining popularity for trapeziometacarpal joint (TMCJ) arthritis, with evolving indications, surgical technique and rehabilitation. The aim of this study was to obtain detailed insight into the variations in indications, surgical technique and rehabilitation for TMCJ arthroplasty with dual mobility implants, across a large international cohort of surgeons. The secondary aim was to analyse if there were differences in TMCJ arthroplasty between highly and less experienced surgeons.

Methods: An anonymised online survey was developed and distributed to the international hand surgery community of surgeons performing TMCJ arthroplasty. Responses were summarised, and a sub-analysis comparing indications, contra-indications, surgical technique, implant placement, rehabilitation and complications between highly and less experienced surgeons was performed.

Results: Of the 203 included respondents, 59 were considered highly experienced. Most respondents perform TMCJ arthroplasty under regional anaesthesia (84%), via a dorsolateral approach (78%) and with image-guidance for cup placement (84%). However, there is considerable variation in handling of scaphotrapeziotrapezoidal (STT) arthritis, cup positioning landmarks, postoperative immobilisation, first extensor compartment release and revision techniques. Highly experienced surgeons performed TMCJ arthroplasty for a larger proportion of their patients undergoing surgery for TMCJ arthritis, and a trapezium smaller than 8 mm or STT-OA was less frequently considered a contra-indication. Highly experienced surgeons preferred freehand osteotomy of the metacarpal and allowed office workers to return to work earlier.

Conclusions: This survey shows that there is considerable variation in (contra)indications, surgical technique and rehabilitation amongst surgeons performing TMCJ arthroplasty, but only a few differences between highly and less experienced surgeons were identified. This data provides a reference for surgeons who want to familiarise themselves with increasingly popular procedure and may help surgeons already performing TMCJ arthroplasty to identify potential topics for future research to optimise its outcome.

Level of Evidence: Level V (Therapeutic)

Background: This study aimed to investigate the effect of thumb metacarpal osteotomy on dorsal subluxation of the carpometacarpal (CMC) joint and compare the effects of early and advanced osteoarthritis (OA).

Methods: We retrospectively reviewed 42 thumbs of 37 patients who underwent metacarpal osteotomy with a postoperative extension angle of 90° or more between January 2018 and October 2021 and were followed up for more than 2 years. The thumbs were classified into two groups: early OA (Eaton stage I or II) and advanced OA (Eaton stage III). We measured the reduction ratio, which was defined as the ratio of improvement in dorsal subluxation, at 3 months and 1 year postoperatively, and at the latest follow-up. We statistically compared the reduction ratio between the two groups and investigated the factors affecting the reduction ratio using correlation analysis.

Results: The reduction ratio was significantly higher in the early OA group than in the advanced OA group at 3 months after surgery, whereas no significant difference was found between the two groups at 1 year after surgery and at the latest follow-up. A significant positive correlation was detected between the reduction ratio and the postoperative extension angle.

Conclusions: First metacarpal osteotomy reduces dorsal subluxation in both early- and advanced-stage CMC OA. This procedure yields immediate marked reduction in early-stage OA, while improvement of the subluxation progressed gradually in advanced-stage OA.

Level of Evidence: Level IV (Therapeutic)

Background: WALANT has gained much popularity in recent years, especially with COVID-19. However, a recent survey of the American Society for Surgery of the Hand membership (i.e. attendings/consultants) showed that only 17% were exposed to WALANT during residency or fellowship training. There is much interest in WALANT from trainees, but interpretation of the type and volume to be administered is highly varied.

Methods: The aims of this study were (1) to survey a group of plastic surgery trainees in the UK about their knowledge of WALANT formulas, and (2) to compare trainee logbook records of WALANT procedures (if available) with published data from the UK.

Results: All trainees were familiar with the ‘standard’ WALANT formula (1% lidocaine, 1:100,000 adrenaline ± 8.4% NaHCO₃) described by Lalonde. However, because of local formularies, rather than 1:100,000 adrenaline, all used 1:200,000 adrenaline as it comes premixed in the UK. Other formulas used by UK trainees included 0.5% bupivacaine + 1:200,000 adrenaline, and mixing 1% lidocaine + 1:200,000 adrenaline with 1% lidocaine 1:1. In comparing available trainee WALANT records with published UK data, the average volume of WALANT used was 6.6 mls in the current study versus 12.9 mls for similar procedures (wound debridement and skin closure ± local flap, digital nerve repair, fingertip reconstruction, thenar injuries, phalangeal fracture and single digit extensor repair); specifically, for single digit flexor tendon repairs, this was 10 mls versus 16.3 mls.

Conclusions: While the British Society for Surgery of the Hand (BSSH) have developed official guidance for the use of WALANT in the UK, it appears there remains much variation in interpretation and hence, application. Comparison of trainee logbook records of common hand surgery procedures suggests that most can be done with much less WALANT administered than previously reported, with safe and reproducible results.

Level of Evidence: Level IV (Therapeutic)

We describe a 13-year-old boy with piso-hamate coalition confirmed by X-ray. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed type 1 coalition according to the classification of DeVilliers Minnaar. Piso-hamate coalition is rare, and suspicions should be raised in instances of chronic ulnar-sided wrist pain, particularly in individuals with a history of elevated hand usage, especially amongst athletes engaging in intensive hand grip activities. Surgical resection of the synchondrosis site between the pisiform and the hamate is an efficacious intervention that can mitigate pain.

Level of Evidence: Level V (Therapeutic)

Arthroplasty of the small joints of the hand and fingers is a complex problem facing the hand surgeon. Pyrocarbon implants have been available for several decades. They were originally thought to provide better functional outcomes than silicone implants in patients, mostly due to recreation of the joint anatomy. In a recent publication, pyrocarbon proximal interphalangeal joint (PIPJ) arthroplasty was found to have a higher complication and revision rate. We present a patient with pyrocarbon metallosis of the PIPJ in a revision arthroplasty procedure.

Level of Evidence: Level V (Therapeutic)

An injury to the ulnar collateral ligament (UCL) of the metacarpophalangeal joint (MCPJ) of the thumb is a common injury, widely referred to as a skier’s thumb. The rupture usually occurs at the distal insertion. In the classical technique, the adductor aponeurosis is divided to access the torn UCL and the MCPJ and repaired after ligament repair/reinsertion. We describe a surgical approach to the UCL that does not require division of the adductor aponeurosis.

Level of Evidence: Level V (Therapeutic)