Diana M. Perriman

Background: It is controversial whether or not the carpometacarpal joint (CMCJ) should be included in total wrist arthrodesis (TWA). Complications commonly occur at this site and studies examining its inclusion and exclusion are conflicting. A randomised clinical trial comparing wrist arthrodesis with CMCJ arthrodesis and spanning plate to wrist arthrodesis with CMCJ preservation and non-CMCJ spanning plate has not been performed. Method: A single centre randomised clinical trial including 120 adults with end-stage isolated wrist arthritis will be performed to compare TWA with and without the CMCJ included in the arthrodesis. The primary outcome is complications in the first post-operative year. Secondary outcomes are Disabilities of the Arm, Shoulder and Hand (DASH) score, Patient Rated Wrist Evaluation (PRWE) and grip strength measured at 1, 2 and 5 years. Late complications, return to work and satisfaction will also be recorded. Discussion: It is unknown whether the CMCJ should be included in TWA. This trial will contribute to an improved understanding of optimal management of the CMCJ in total wrist arthrodesis. Trial registration: This trial was prospectively registered with the Australia New Zealand Clinical Trials Registry with identifying number ACTRN12621000169842 on the 16th February 2021. WHO: U1111–12626523. ANZCTR: ACTRN12621000169842

Introduction: Kayak racing has been an Olympic sport since 1936. The sport is evolving with the introduction of ocean skis and stand-up-paddle boards (SUP). Musculoskeletal injury incidence surveys have been conducted for ultra-marathon events, but no data have been published for other racing formats. Objective: To identify and compare the rates and types of injuries sustained by paddling athletes as a function of discipline and training parameters in Sprint, Marathon, Ultra-Marathon, and Ocean events. Methods: Competitors from 6 kayak and/or ocean surf-ski races in Australia were surveyed. Before each race, competitors were asked to complete a questionnaire. The questionnaire investigated paddling-related injuries over the previous 5 years, athlete morphology, flexibility, equipment and its setup, training volume, and environment. Results: Five hundred eighty-three competitors were surveyed. Disciplines included 173 racing-kayak (K1), 202 touring-kayak, 146 ocean-skis, 42 SUP, and 20 other. The top 5 paddling-related injuries were shoulder (31%), low back (23.5%), wrist (16.5%), neck (13.7%), and elbow (11.0%). The highest percentage of injury was found in K1 paddlers for shoulder (40.5%), SUP for low back (33.3%), and ocean-ski for wrist (22.6%). After controlling for on-water training hours, the relative risk (RR) of wrist injury was significantly increased in ocean-ski paddlers (1.86) and in paddlers with decreased flexibility (1.53-1.83). Relative risk of shoulder and low-back injury was significantly increased in athletes with lower training volumes (1.82-2.07). Younger athletes had lower RR of wrist and shoulder injury (0.58-0.62).

Introduction: A kinematic measurement method combining dynamic motion and imaging, which captures the behaviour of the hip at terminal motion, may offer improved diagnostic accuracy and enhance our understanding of the mechanics of femoroacetabular impingement (FAI). Methods: 3 embalmed cadaveric hip/pelvis specimens with implanted Roentgen Stereophotogrammetric Analysis (RSA) beads were mounted on a custom rig and imaged with a fluoroscope in four poses to simulate a clinical impingement examination: in hip extension and in three positions: near impingement, early impingement and late impingement while simulating a flexion/adduction/internal rotation manoeuvre. Hip joint kinematics were measured using 2 methods and compared: RSA (gold standard) and a custom 3-dimensional to 2-dimensional (3D–2D) image registration method which matches 3D models developed from CT to 2D fluoroscopic images. Results: Using RSA as the gold standard, bias and precision of hip joint rotations measured using 3D–2D registration demonstrated maximums of 1.64° and 3.96°, respectively. However, if the single outlier was removed, bias and precision were 0.55° and 1.38°. Bias and precision of translations had maximums of 0.51 mm and 0.77 mm, respectively. Conclusions: This 3D to 2D registration method may offer a clinically useful solution for dynamic assessment of hip impingement. If 5-mm translation and 10° of rotation represent a clinically significant difference in hip kinematics, the method’s accuracy of approximately 1 mm displacement and 1° rotation should enable detection of significant clinical differences.

Background: Pelvic discontinuity is a rare condition that is treated with a range of implant constructs. However, surgical failure rates are high, and outcome data are inconsistent. It is therefore difficult to gain a clear picture of whether recently developed constructs (antiprotrusio cage [APC], cup-cage, custom triflange, and porous metal) provide better outcomes in terms of mechanical failure and complications in the short to long terms. This study investigated the failure and complication rates associated with cage constructs and porous metal technologies. Methods: A systematic review and meta-analysis were performed according to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines to evaluate the studies showing pelvic discontinuity in revision total hip arthroplasty. Data retrieved included the intervention performed, length of follow-up, mechanical failure, and other complication rates (dislocation, infection, neurological, loosening, migration). Study quality was assessed with the Methodological Index for Non-Randomized Studies (MINORS) instrument. Pooled mechanical failure and complication rates were calculated using MetaXL 5.3. Results: None of the included 30 articles (n = 585 hips) were of high quality. The meta-analyses revealed a mechanical failure rate of 14% for all constructs combined. Custom triflange (5%) and cup-cage (7%) had the lowest mechanical failure rates compared with the commonly used APC (25%) and porous metal (12%). The overall other complication rate was 28%, with cup-cage lower at 21% compared with APC (34%) and custom triflange (28%). Long-term evidence investigating both interventions and porous metal technology is limited. Conclusions: Mechanical failure rates for cup-cage and custom triflange were lowest. The other complication rate for cup-cage was lower than the pooled average. The study quality was limited, indicating a need for better studies and/or a registry. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.