Aims. Micromotion of the polyethylene (PE) inlay may contribute to backside PE wear in addition to articulate wear of total knee arthroplasty (TKA). Using radiostereometric analysis (RSA) with tantalum beads in the PE inlay, we evaluated PE micromotion and its relationship to PE wear. Methods. A total of 23 patients with a mean age of 83 years (77 to 91), were available from a RSA study on cemented TKA with Maxim tibial components (Zimmer Biomet). PE inlay migration, PE wear, tibial component migration, and the anatomical knee axis were evaluated on weightbearing stereoradiographs. PE inlay wear was measured as the deepest penetration of the femoral component into the PE inlay. Results. At mean six years’ follow-up, the PE wear rate was 0.08 mm/year (95% confidence interval 0.06 to 0.09 mm/year). PE inlay external rotation was below the precision limit and did not influence PE wear. Varus knee alignment did not influence PE wear (p = 0.874), but increased tibial component total translation (p = 0.041). Conclusion. The PE inlay was well fixed and there was no relationship between PE stability and PE wear. The PE wear rate was low and similar in the medial and lateral compartments. Varus knee alignment did not influence PE wear. Cite this article: Bone Joint Res 2024;13(5):226–236

The June 2024 Shoulder & Elbow Roundup. 360. looks at: Reverse versus anatomical total shoulder replacement for osteoarthritis? A UK national picture; Acute rehabilitation following traumatic anterior shoulder dislocation (ARTISAN): pragmatic, multicentre, randomized controlled trial; acid for rotator cuff repair: a systematic review and meta-analysis of randomized controlled trials; Metal or ceramic humeral head total shoulder arthroplasty: an analysis of data from the National Joint Registry; Platelet-rich plasma has better results for long-term functional improvement and pain relief for lateral epicondylitis: a systematic review and meta-analysis of randomized controlled trials; Quantitative fatty infiltration and 3D muscle volume after nonoperative treatment of symptomatic rotator cuff tears: a prospective MRI study of 79 patients; Locking plates for non-osteoporotic proximal humeral fractures in the long term; A systematic review of the treatment of primary acromioclavicular joint osteoarthritis

Salter-Harris II fractures of the distal tibia affect children frequently, and when they are displaced present a treatment dilemma. Treatment primarily aims to restore alignment and prevent premature physeal closure, as this can lead to angular deformity, limb length difference, or both. Current literature is of poor methodological quality and is contradictory as to whether conservative or surgical management is superior in avoiding complications and adverse outcomes. A state of clinical equipoise exists regarding whether displaced distal tibial Salter-Harris II fractures in children should be treated with surgery to achieve anatomical reduction, or whether cast treatment alone will lead to a satisfactory outcome. Systematic review and meta-analysis has concluded that high-quality prospective multicentre research is needed to answer this question. The Outcomes of Displaced Distal tibial fractures: Surgery Or Casts in KidS (ODD SOCKS) trial, funded by the National Institute for Health and Care Research, aims to provide this high-quality research in order to answer this question, which has been identified as a top-five research priority by the British Society for Children’s Orthopaedic Surgery. Cite this article: Bone Joint J 2023;105-B(5):471–473

Aims. Leg length discrepancy (LLD) is a common pre- and postoperative issue in total hip arthroplasty (THA) patients. The conventional technique for measuring LLD has historically been on a non-weightbearing anteroposterior pelvic radiograph; however, this does not capture many potential sources of LLD. The aim of this study was to determine if long-limb EOS radiology can provide a more reproducible and holistic measurement of LLD. Methods. In all, 93 patients who underwent a THA received a standardized preoperative EOS scan, anteroposterior (AP) radiograph, and clinical LLD assessment. Overall, 13 measurements were taken along both anatomical and functional axes and measured twice by an orthopaedic fellow and surgical planning engineer to calculate intraoperator reproducibility and correlations between measurements. Results. Strong correlations were observed for all EOS measurements (r. s. > 0.9). The strongest correlation with AP radiograph (inter-teardrop line) was observed for functional-ASIS-to-floor (functional) (r. s. = 0.57), much weaker than the correlations between EOS measurements. ASIS-to-ankle measurements exhibited a high correlation to other linear measurements and the highest ICC (r. s. = 0.97). Using anterior superior iliac spine (ASIS)-to-ankle, 33% of patients had an absolute LLD of greater than 10 mm, which was statistically different from the inter-teardrop LLD measurement (p < 0.005). Discussion. We found that the conventional measurement of LLD on AP pelvic radiograph does not correlate well with long leg measurements and may not provide a true appreciation of LLD. ASIS-to-ankle demonstrated improved detection of potential LLD than other EOS and radiograph measurements. Full length, functional imaging methods may become the new gold standard to measure LLD. Cite this article: Bone Jt Open 2022;3(12):960–968

Displaced fractures of the distal radius in children are usually reduced under sedation or general anaesthesia to restore anatomical alignment before the limb is immobilized. However, there is growing evidence of the ability of the distal radius to remodel rapidly, raising doubts over the benefit to these children of restoring alignment. There is now clinical equipoise concerning whether or not young children with displaced distal radial fractures benefit from reduction, as they have the greatest ability to remodel. The Children’s Radius Acute Fracture Fixation Trial (CRAFFT), funded by the National Institute for Health and Care Research, aims to definitively answer this question and determine how best to manage severely displaced distal radial fractures in children aged up to ten years. Cite this article: Bone Joint J 2024;106-B(1):16–18

Aims. Posterior column plating through the single anterior approach reduces the morbidity in acetabular fractures that require stabilization of both the columns. The aim of this study is to assess the effectiveness of posterior column plating through the anterior intrapelvic approach (AIP) in the management of acetabular fractures. Methods. We retrospectively reviewed the data from R G Kar Medical College, Kolkata, India, from June 2018 to April 2023. Overall, there were 34 acetabulum fractures involving both columns managed by medial buttress plating of posterior column. The posterior column of the acetabular fracture was fixed through the AIP approach with buttress plate on medial surface of posterior column. Mean follow-up was 25 months (13 to 58). Accuracy of reduction and effectiveness of this technique were measured by assessing the Merle d’Aubigné score and Matta’s radiological grading at one year and at latest follow-up. Results. Immediate postoperative radiological Matta’s reduction accuracy showed anatomical reduction (0 to 1 mm) in 23 cases (67.6%), satisfactory (2 to 3 mm) in nine (26.4%), and unsatisfactory (> 3 mm) in two (6%). Merle d’Aubigné score at the end of one year was calculated to be excellent in 18 cases (52.9%), good in 11 (32.3%), fair in three (8.8%), and poor in two (5.9%). Matta’s radiological grading at the end of one year was calculated to be excellent in 16 cases (47%), good in nine (26.4%), six in fair (17.6%), and three in poor (8.8%). Merle d’Aubigné score at latest follow-up deteriorated by one point in some cases, but the grading remained the same; Matta’s radiological grading at latest follow-up also remained unchanged. Conclusion. Stabilization of posterior column through AIP by medial surface plate along the sciatic notch gives good stability to posterior column, and at the same time can avoid morbidity of the additional lateral window. Cite this article: Bone Jt Open 2024;5(2):147–153

The February 2023 Shoulder & Elbow Roundup. 360. looks at: Arthroscopic capsular release or manipulation under anaesthesia for frozen shoulder?; Distal biceps repair through a single incision?; Distal biceps tendon ruptures: diagnostic strategy through physical examination; Postoperative multimodal opioid-sparing protocol vs standard opioid prescribing after knee or shoulder arthroscopy: a randomized clinical trial; Graft healing is more important than graft technique in massive rotator cuff tear; Subscapularis tenotomy versus peel after anatomic shoulder arthroplasty; Previous rotator cuff repair increases the risk of revision surgery for periprosthetic joint infection after reverse shoulder arthroplasty; Conservative versus operative treatment of acromial and scapular spine fractures following reverse total shoulder arthroplasty

Aims. The aim of this study was to examine the implant accuracy of custom-made partial pelvis replacements (PPRs) in revision total hip arthroplasty (rTHA). Custom-made implants offer an option to achieve a reconstruction in cases with severe acetabular bone loss. By analyzing implant deviation in CT and radiograph imaging and correlating early clinical complications, we aimed to optimize the usage of custom-made implants. Methods. A consecutive series of 45 (2014 to 2019) PPRs for Paprosky III defects at rTHA were analyzed comparing the preoperative planning CT scans used to manufacture the implants with postoperative CT scans and radiographs. The anteversion (AV), inclination (IC), deviation from the preoperatively planned implant position, and deviation of the centre of rotation (COR) were explored. Early postoperative complications were recorded, and factors for malpositioning were sought. The mean follow-up was 30 months (SD 19; 6 to 74), with four patients lost to follow-up. Results. Mean CT defined discrepancy (Δ) between planned and achieved AV and IC was 4.5° (SD 3°; 0° to 12°) and 4° (SD 3.5°; 1° to 12°), respectively. Malpositioning (Δ > 10°) occurred in five hips (10.6%). Native COR reconstruction was planned in 42 cases (93%), and the mean 3D deviation vector was 15.5 mm (SD 8.5; 4 to 35). There was no significant influence in malpositioning found for femoral stem retention, surgical approach, or fixation method. Conclusion. At short-term follow-up, we found that PPR offers a viable solution for rTHA in cases with massive acetabular bone loss, as highly accurate positioning can be accomplished with meticulous planning, achieving anatomical reconstruction. Accuracy of achieved placement contributed to reduced complications with no injury to vital structures by screw fixation. Cite this article: Bone Joint J 2022;104-B(10):1110–1117

The June 2024 Wrist & Hand Roundup. 360. looks at: One-year outcomes of the anatomical front and back reconstruction for scapholunate dissociation; Limited intercarpal fusion versus proximal row carpectomy in the treatment of SLAC or SNAC wrist: results after 3.5 years; Prognostic factors for clinical outcomes after arthroscopic treatment of traumatic central tears of the triangular fibrocartilage complex; The rate of nonunion in the MRI-detected occult scaphoid fracture: a multicentre cohort study; Does correction of carpal malalignment influence the union rate of scaphoid nonunion surgery?; Provision of a home-based video-assisted therapy programme in thumb carpometacarpal arthroplasty; Is replantation associated with better hand function after traumatic hand amputation than after revision amputation?; Diagnostic performance of artificial intelligence for detection of scaphoid and distal radius fractures: a systematic review

Aims. Mechanical impingement of the iliopsoas (IP) tendon accounts for 2% to 6% of persistent postoperative pain after total hip arthroplasty (THA). The most common initiator is anterior acetabular component protrusion, where the anterior margin is not covered by anterior acetabular wall. A CT scan can be used to identify and measure this overhang; however, no threshold exists for determining symptomatic anterior IP impingement due to overhang. A case-control study was conducted in which CT scan measurements were used to define a threshold that differentiates patients with IP impingement from asymptomatic patients after THA. Methods. We analyzed the CT scans of 622 patients (758 THAs) between May 2011 and May 2020. From this population, we identified 136 patients with symptoms suggestive of IP impingement. Among them, six were subsequently excluded: three because the diagnosis was refuted intraoperatively, and three because they had another obvious cause of impingement, leaving 130 hips (130 patients) in the study (impingement) group. They were matched to a control group of 138 asymptomatic hips (138 patients) after THA. The anterior acetabular component overhang was measured on an axial CT slice based on anatomical landmarks (orthogonal to the pelvic axis). Results. The impingement group had a median overhang of 8 mm (interquartile range (IQR) 5 to 11) versus 0 mm (IQR 0 to 4) for the control group (p < 0.001). Using receiver operating characteristic curves, an overhang threshold of 4 mm was best correlated with a diagnosis of impingement (sensitivity 79%, specificity 85%; positive predictive value 75%, negative predictive value 85%). Conclusion. Pain after THA related to IP impingement can be reasonably linked to acetabular overhang if it exceeds 4 mm on a CT scan. Below this threshold, it seems logical to look for another cause of IP irritation or another reason for the pain after THA before concluding that impingement is present. Cite this article: Bone Joint J 2024;106-B(3 Supple A):97–103

Aims. The impact of a diaphyseal femoral deformity on knee alignment varies according to its severity and localization. The aims of this study were to determine a method of assessing the impact of diaphyseal femoral deformities on knee alignment for the varus knee, and to evaluate the reliability and the reproducibility of this method in a large cohort of osteoarthritic patients. Methods. All patients who underwent a knee arthroplasty from 2019 to 2021 were included. Exclusion criteria were genu valgus, flexion contracture (> 5°), previous femoral osteotomy or fracture, total hip arthroplasty, and femoral rotational disorder. A total of 205 patients met the inclusion criteria. The mean age was 62.2 years (SD 8.4). The mean BMI was 33.1 kg/m. 2. (SD 5.5). The radiological measurements were performed twice by two independent reviewers, and included hip knee ankle (HKA) angle, mechanical medial distal femoral angle (mMDFA), anatomical medial distal femoral angle (aMDFA), femoral neck shaft angle (NSA), femoral bowing angle (FBow), the distance between the knee centre and the top of the FBow (DK), and the angle representing the FBow impact on the knee (C’KS angle). Results. The FBow impact on the mMDFA can be measured by the C’KS angle. The C’KS angle took the localization (length DK) and the importance (FBow angle) of the FBow into consideration. The mean FBow angle was 4.4° (SD 2.4; 0 to 12.5). The mean C’KS angle was 1.8° (SD 1.1; 0 to 5.8). Overall, 84 knees (41%) had a severe FBow (> 5°). The radiological measurements showed very good to excellent intraobserver and interobserver agreements. The C’KS increased significantly when the length DK decreased and the FBow angle increased (p < 0.001). Conclusion. The impact of the diaphyseal femoral deformity on the mechanical femoral axis is measured by the C’KS angle, a reliable and reproducible measurement. Cite this article: Bone Jt Open 2023;4(4):262–272

Aims. The aim of this study was to analyze how proximal radial neck resorption (PRNR) starts and progresses radiologically in two types of press-fit radial head arthroplasties (RHAs), and to investigate its clinical relevance. Methods. A total of 97 patients with RHA were analyzed: 56 received a bipolar RHA (Group 1) while 41 received an anatomical implant (Group 2). Radiographs were performed postoperatively and after three, six, nine, and 12 weeks, six, nine, 12, 18, and 24 months, and annually thereafter. PRNR was measured in all radiographs in the four radial neck quadrants. The Mayo Elbow Performance Score (MEPS), the abbreviated version of the Disabilities of the Arm, Shoulder, and Hand questionnaire (QuickDASH), and the patient-assessed American Shoulder and Elbow Surgeons score - Elbow (pASES-E) were used for the clinical assessment. Radiological signs of implant loosening were investigated. Results. The mean follow-up was six years (2 to 14). PRNR started after a mean of 7.5 weeks (SD 2.1) and progressed significantly during the first two years, by the end of which the bone resorption stabilized. PRNR was detected in 81% (n = 45) of patients in Group 1 and 88% (n = 36) in Group 2. The final mean PRNR was 3.0 mm (SD 2.3) in Group 1 and 3.7 mm (SD 2.5) in Group 2. The mean MEPS, QuickDASH, and pASES-E were 95.9 (SD 11.5), 4.4 (SD 9.2), and 94.8 (SD 10.9) in Group 1 and 92.2 (SD 16.2), 9.9 (SD 21.5), and 90.8 (SD 15) in Group 2, respectively. No significant differences were observed between groups in the clinical and radiological outcomes. No correlations were found between PRNR and the clinical results. Conclusion. PRNR after press-fit RHA is a common radiological finding that develops in the first 24 months before stabilizing definitively. PRNR does not affect the clinical results or implant survival in the mid term. Cite this article: Bone Joint J 2023;105-B(8):905–911

Aims. The purpose of this study was to compare reoperation and revision rates of double plating (DP), single plating using a lateral locking plate (SP), or distal femoral arthroplasty (DFA) for the treatment of periprosthetic distal femur fractures (PDFFs). Methods. All patients with PDFF primarily treated with DP, SP, or DFA between 2008 and 2022 at a university teaching hospital were included in this retrospective cohort study. The primary outcome was revision surgery for failure following DP, SP, or DFA. Secondary outcome measures included any reoperation, length of hospital stay, and mortality. All basic demographic and relevant implant and injury details were collected. Radiological analysis included fracture classification and evaluation of metaphyseal and medial comminution. Results. A total of 111 PDFFs (111 patients, median age 82 years (interquartile range (IQR) 75 to 88), 86% female) with 32 (29%) Su classification 1, 37 (34%) Su 2, and 40 (37%) Su 3 fractures were included. The median follow-up was 2.5 years (IQR 1.2 to 5.0). DP, SP, and DFA were used in 15, 66, and 30 patients, respectively. Compared to SP, patients treated with DP were more likely to have metaphyseal comminution (47% vs 14%; p = 0.009), to be low fractures (47% vs 11%; p = 0.009), and to be anatomically reduced (100% vs 71%; p = 0.030). Patients selected for DFA displayed comparable amounts of medial/metaphyseal comminution as those who underwent DP. At a minimum follow-up of two years, revision surgery for failure was performed in 11 (9.9%) cases at a median of five months (IQR 2 to 9): 0 DP patients (0%), 9 SP (14%), and 2 DFA (6.7%) (p = 0.249). Conclusion. Using a strategy of DP fixation in fractures, where the fracture was low but there was enough distal bone to accommodate locking screws, and where there is metaphyseal comminution, resulted in equivalent survival free from revision or reoperation compared to DFA and SP fixation. Cite this article: Bone Jt Open 2024;5(6):489–498

Aims. This study aimed to investigate the incidence of ≥ 5 mm asymmetry in lower and whole leg lengths (LLs) in patients with unilateral osteoarthritis (OA) secondary to developmental dysplasia of the hip (DDH-OA) and primary hip osteoarthritis (PHOA), and the relationship between lower and whole LL asymmetries and femoral length asymmetry. Methods. In total, 116 patients who underwent unilateral total hip arthroplasty were included in this study. Of these, 93 had DDH-OA and 23 had PHOA. Patients with DDH-OA were categorized into three groups: Crowe grade I, II/III, and IV. Anatomical femoral length, femoral length greater trochanter (GT), femoral length lesser trochanter (LT), tibial length, foot height, lower LL, and whole LL were evaluated using preoperative CT data of the whole leg in the supine position. Asymmetry was evaluated in the Crowe I, II/III, IV, and PHOA groups. Results. The incidences of whole and lower LL asymmetries were 40%, 62.5%, 66.7%, and 26.1%, and 21.7%, 20.8%, 55.6%, and 8.7% in the Crowe I, II/III, and IV, and PHOA groups, respectively. The incidence of tibial length asymmetry was significantly higher in the Crowe IV group (44.4%) than that in the PHOA group (4.4%). In all, 50% of patients with DDH-OA with femoral length GT and LT asymmetries had lower LL asymmetry, and 75% had whole LL asymmetry. The incidences of lower and whole LL asymmetries were 20% and 42.9%, respectively, even in the absence of femoral length GT and LT asymmetries. Conclusion. Overall, 43% of patients with unilateral DDH-OA without femoral length asymmetry had whole LL asymmetry of ≥ 5 mm. Thus, both the femur length and whole LL should be measured to accurately assess LL discrepancy in patients with unilateral DDH-OA. Cite this article: Bone Jt Open 2024;5(2):79–86

Aims. The purpose of this study was to determine the association between prior sleeve gastrectomy in patients undergoing primary total hip and knee arthroplasty, and 90-day complications, incidence of revision arthroplasty, and patient-reported outcome scores at final follow-up. Methods. This is a retrospective, single-centre analysis. Patients undergoing primary hip or knee arthroplasty with a prior sleeve gastrectomy were eligible for inclusion (n = 80 patients). A morbidly obese control group was established from the same institutional registry using a 1:2 match, for cases:controls with arthroplasty based on propensity score using age, sex, pre-sleeve gastrectomy BMI, Current Procedural Terminology code to identify anatomical location, and presurgical haemoglobin A1C. Outcomes included 90-day complications, incidence of revision arthroplasty, and patient-reported outcome scores at final follow-up. Multivariable logistic regressions evaluated associations of underlying preoperative demographic and treatment characteristics with outcomes. Results. Complications within 90 days of surgery were increased in the sleeve gastrectomy group relative to the obese control group after controlling for underlying preoperative demographic characteristics (odds ratio (OR) 4.00 (95% CI 1.14 to 13.9); p = 0.030). Postoperative revisions were similar in the sleeve gastrectomy group relative to the obese control group after controlling for underlying preoperative demographic characteristics (OR 17.8 (95% CI 0.64 to 494.3); p = 0.090). Patient-Reported Outcomes Measurement Information System (PROMIS) depression decreased by a greater amount from pre- to postoperative in the obese controls relative to the sleeve gastrectomy group (OR 4.04 (95% CI 0.06 to 8.02); p = 0.047). PROMIS pain interference and physical function change from pre- to postoperative was not associated with sleeve gastrectomy status. Conclusion. We found a higher rate of complications at 90 days in patients who underwent sleeve gastrectomy prior to primary hip or knee arthroplasty relative to a matched, obese control population. Prosthetic revision rates were similar between the two groups, while improvements in PROMIS depression scores were larger in the obese cohort. This study suggests that sleeve gastrectomy to achieve preoperative weight loss prior to arthroplasty surgery may not mitigate early complication risks in obese patient populations. Cite this article: Bone Joint J 2024;106-B(9):935–941

Aims. The aim of this study was to perform the first population-based description of the epidemiological and health economic burden of fracture-related infection (FRI). Methods. This is a retrospective cohort study of operatively managed orthopaedic trauma patients from 1 January 2007 to 31 December 2016, performed in Queensland, Australia. Record linkage was used to develop a person-centric, population-based dataset incorporating routinely collected administrative, clinical, and health economic information. The FRI group consisted of patients with International Classification of Disease 10th Revision diagnosis codes for deep infection associated with an implanted device within two years following surgery, while all others were deemed not infected. Demographic and clinical variables, as well as healthcare utilization costs, were compared. Results. There were 111,402 patients operatively managed for orthopaedic trauma, with 2,775 of these (2.5%) complicated by FRI. The development of FRI had a statistically significant association with older age, male sex, residing in rural/remote areas, Aboriginal or Torres Strait Islander background, lower socioeconomic status, road traffic accident, work-related injuries, open fractures, anatomical region (lower limb, spine, pelvis), high injury severity, requiring soft-tissue coverage, and medical comorbidities (univariate analysis). Patients with FRI had an eight-times longer median inpatient length of stay (24 days vs 3 days), and a 2.8-times higher mean estimated inpatient hospitalization cost (AU$56,565 vs AU$19,773) compared with uninfected patients. The total estimated inpatient cost of the FRI cohort to the healthcare system was AU$156.9 million over the ten-year period. Conclusion. The results of this study advocate for improvements in trauma care and infection management, address social determinants of health, and highlight the upside potential to improve prevention and treatment strategies. Cite this article: Bone Joint J 2024;106-B(1):77–85

Aims. Acute and chronic injuries of the interosseus membrane can result in longitudinal instability of the forearm. Reconstruction of the central band of the interosseus membrane can help to restore biomechanical stability. Different methods have been used to reconstruct the central band, including tendon grafts, bone-ligament-bone grafts, and synthetic grafts. This Idea, Development, Exploration, Assessment, and Long-term (IDEAL) phase 1 study aims to review the clinical results of reconstruction using a synthetic braided cross-linked graft secured at either end with an Endobutton to restore the force balance between the bones of the forearm. Methods. An independent retrospective review was conducted of a consecutive series of 21 patients with longitudinal instability injuries treated with anatomical central band reconstruction between February 2011 and July 2019. Patients with less than 12 months’ follow-up or who were treated acutely were excluded, leaving 18 patients in total. Preoperative clinical and radiological assessments were compared with prospectively gathered data using range of motion and the abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH) functional outcome score. Results. Of the 18 patients (nine male, nine female) who met the inclusion criteria, the median follow-up was 8.5 years (interquartile range (IQR) 5.6 to 10). Their mean age was 49 years (SD 11). The mean extension improved significantly from 38° (SD 15°) to 24° (SD 9°) (p = 0.027), with a mean flexion-extension arc change from 81° (SD 27°) to 93° (SD 30°) (p = 0.172) but with no forearm rotational improvement (p = 0.233) at latest follow-up. The QuickDASH functional score improved significantly from 80 (SD 14) to 52 (SD 26) following reconstruction (p = 0.031), but generally the level of disability remains high. Radiological assessment showed no progression of proximal migration of the radius, with a stable interbutton distance and ulnar variance from immediate postoperative radiograph to the latest follow-up. Conclusion. Central band interosseus membrane reconstruction using a synthetic braided cross-linked graft can improve patient-rated arm function and range of motion, but significant functional deficits remain in patients with chronic injuries. Cite this article: Bone Joint J 2024;106-B(2):182–188

Aims. There is ambiguity surrounding the degree of scaphoid union required to safely allow mobilization following scaphoid waist fracture. Premature mobilization could lead to refracture, but late mobilization may cause stiffness and delay return to normal function. This study aims to explore the risk of refracture at different stages of scaphoid waist fracture union in three common fracture patterns, using a novel finite element method. Methods. The most common anatomical variant of the scaphoid was modelled from a CT scan of a healthy hand and wrist using 3D Slicer freeware. This model was uploaded into COMSOL Multiphysics software to enable the application of physiological enhancements. Three common waist fracture patterns were produced following the Russe classification. Each fracture had differing stages of healing, ranging from 10% to 90% partial union, with increments of 10% union assessed. A physiological force of 100 N acting on the distal pole was applied, with the risk of refracture assessed using the Von Mises stress. Results. Overall, 90% to 30% fracture unions demonstrated a small, gradual increase in the Von Mises stress of all fracture patterns (16.0 MPa to 240.5 MPa). All fracture patterns showed a greater increase in Von Mises stress from 30% to 10% partial union (680.8 MPa to 6,288.6 MPa). Conclusion. Previous studies have suggested 25%, 50%, and 75% partial union as sufficient for resuming hand and wrist mobilization. This study shows that 30% union is sufficient to return to normal hand and wrist function in all three fracture patterns. Both 50% and 75% union are unnecessary and increase the risk of post-fracture stiffness. This study has also demonstrated the feasibility of finite element analysis (FEA) in scaphoid waist fracture research. FEA is a sustainable method which does not require the use of finite scaphoid cadavers, hence increasing accessibility into future scaphoid waist fracture-related research. Cite this article: Bone Jt Open 2023;4(8):612–620

Aims. The paediatric trigger thumb is a distinct clinical entity with unique anatomical abnormalities. The aim of this study was to present the long-term outcomes of A1 pulley release in idiopathic paediatric trigger thumbs based on established patient-reported outcome measures. Methods. This study was a cross-sectional, questionnaire-based study conducted at a tertiary care orthopaedic centre. All cases of idiopathic paediatric trigger thumbs which underwent A1 pulley release between 2004 and 2011 and had a minimum follow-up period of ten years were included in the study. The abbreviated version of the Disabilities of Arm, Shoulder and Hand questionnaire (QuickDASH) was administered as an online survey, and ipsi- and contralateral thumb motion was assessed. Results. A total of 67 patients completed the survey, of whom 63 (94%) had full interphalangeal joint extension or hyperextension. Severe metacarpophalangeal joint hyperextension (> 40°) was documented in 15 cases (22%). The median QuickDASH score was 0 (0 to 61), indicating excellent function at a median follow-up of 15 years (10 to 19). Overall satisfaction was high, with 56 patients (84%) reporting the maximal satisfaction score of 5. Among 37 patients who underwent surgery at age ≤ two years, 34 (92%) reported the largest satisfaction, whereas this was the case for 22 of 30 patients (73%) with surgery at aged > two years (p = 0.053). Notta’s nodule resolved in 49 patients (73%) at final follow-up. No residual triggering or revision surgery was observed. Conclusion. Surgical release of A1 pulley in paediatric trigger thumb is an acceptable procedure with excellent functional long-term outcomes. There was a trend towards higher satisfaction with earlier surgery among the patients. Cite this article: Bone Jt Open 2024;5(9):736–741