The triangular fibrocartilage complex (TFCC) is a known stabiliser of the distal radioulnar joint (DRUJ). An injury to these structures can result in significant disability including pain, weakness and joint stiffness. The contribution each of its components makes to the stability of the TFCC is not well understood. This study was undertaken to investigate the role of the individual ligaments of the TFCC and their contribution to joint stability. The study was undertaken in two parts. 30 cadaveric forearms were studied in each group. The ligaments of the TFCC were progressively sectioned and the resulting effect on the stability of the DRUJ was measured. A custom jig was created to apply a 20N force through the distal radius, with the ulna fixed. Experiment one measured the effect on DRUJ translation after TFCC sectioning. Experiment two added the measurement of rotational instability. Part one of the study showed that complete sectioning of the TFCC caused a mean increase in translation of 6.09(±3) mm. Sectioning the palmar radioulnar ligament of the TFCC caused the most translation. Part two demonstrated a change in rotation with a mean of 18 (± 6) degrees following sectioning of the TFCC. There was a progressive increase in rotational instability until the palmar radioulnar ligament was also sectioned. Linear translation consistently increased after sectioning all of the TFCC ligaments, confirming its importance for DRUJ stability. Sectioning of the palmar radioulnar ligament most commonly caused the greatest degree of translation. This suggests injury to this ligament would more likely result in a greater degree of translational instability. The increase in rotation also suggests that this type of instability would be symptomatic in a TFCC injury

Fractures of the distal radius are common, and form a considerable proportion of the trauma workload. We conducted a study to examine the patterns of injury and treatment for adult patients presenting with distal radius fractures to a major trauma centre serving an urban population. We undertook a retrospective cohort study to identify all patients treated at our major trauma centre for a distal radius fracture between 1 June 2018 and 1 May 2021. We reviewed the medical records and imaging for each patient to examine patterns of injury and treatment. We undertook a binomial logistic regression to produce a predictive model for operative fixation or inpatient admission. Overall, 571 fractures of the distal radius were treated at our centre during the study period. A total of 146 (26%) patients required an inpatient admission, and 385 surgical procedures for fractures of the distal radius were recorded between June 2018 and May 2021. The most common mechanism of injury was a fall from a height of one metre or less. Of the total fractures, 59% (n = 337) were treated nonoperatively, and of those patients treated with surgery, locked anterior-plate fixation was the preferred technique (79%; n = 180). The epidemiology of distal radius fractures treated at our major trauma centre replicated the classical bimodal distribution described in the literature. Patient age, open fractures, and fracture classification were factors correlated with the decision to treat the fracture operatively. While most fractures were

Distal ulna fractures (DUF) are commonly associated with distal radius fractures (DRF). Recent evidence suggests that the presence and type DUFs may impact the outcomes of associated healing distal radius fractures. There is currently no standardised and validated classification system for characterising distal ulna fractures. The purpose of this study was to assess the validity of our newly created inclusive classification system for distal ulna fractures, shown to influence distal radius fracture outcomes in a previous study. A classification system for distal ulna fractures was devised based on fracture pattern and location. Type 1 fractures were those in the ulnar styloid, with type 1a involving its apex and Type 1b being in the body of the styloid; Type 2 fractures are proximal to the styloid and involve the ulnar fovea, with type 2t adopting a transverse pattern and type 2o an oblique pattern; Type 3 fractures involve the ulnar head; and type 4 fractures were those proximal to the head, with 4n being through the neck (including the physeal scar) and 4s involving the distal shaft. A questionnaire was distributed to all members of the Canadian Orthopaedics Association in both French and English, asking participants to evaluate 29 radiographic images of distal ulnar fractures. Only one answer was deemed to be correct for all but one radiograph, while for one radiograph there were three fracture types to be identified. There were 129 respondents to the questionnaire. For Type 1a fractures, of the 606 radiographs evaluated 90% answered correctly and 73% of the incorrect answers identified a Type 1b fracture pattern. For Type 1b fractures, of 600 radiographs, 83% were answered correctly, the incorrect answers including Types 1a and 2t fracture types. For Type 2t fractures, of 593 radiographs, 76% were answered correctly, and 90% of the incorrect answers identified a Type 1b fracture pattern. For Type 2o fractures, of 716 radiographs, 87% were answered correctly, and 91% of the incorrect answers were identified as either Type 4n or 2t. For Type 4n fractures, of the 465 radiographs evaluated 84% answered correctly and 80% of the incorrect answers identified a Type 4s fracture pattern. For Type 4s fractures, of the 355 radiographs evaluated 99% answered correctly and 100% of the incorrect answers identified a Type 4n fracture pattern. The results will guide the authors to further distinguish between the definitions of Types 1b and 2t, and 4n and 4s. The Canadian orthopaedic community has demonstrated how readily they can reproduce this new classification system, previously shown to be predictive of radiographic outcomes for the associated distal radius fractures. This new classification is an inclusive and simple way of characterising these fractures with high reliability. This provides treating physicians with a uniform way of describing these fractures, useful both in predicting outcomes and conducting future research

This study reviews the early results of Distal Humeral Hemiarthroplasty(DHH) for distal humeral fracture and proposed a treatment algorithm incorporating the use of this technique in the overall management of distal humeral fractures. DHH was performed on 30 patients (mean 65 years; 29-91) for unreconstructable fractures of the distal humerus or salvage of failed internal fixation. A triceps on approach was used in six and an olecranon osteotomy in 24. A Sorbie Questor prosthesis (Wright Medical Technology) was used in 14 patients and a Latitude (Tornier) in 16. Clinical review at a mean of 25 months (3–88) included the American Shoulder and Elbow Surgeons elbow outcomes instrument (ASES), Mayo Elbow Performance Index (MEPI) and radiological assessment. At follow up of 28 patients mean flexion deformity was 25 degrees, flexion 128 degrees, range of pronosupination 165 degrees, mean ASES 83, MEPI 77 and satisfaction 8/10. Acute cases scored better than salvage cases. Re- operation was required in 16 patients (53%); two revisions to a linked prosthesis for periprosthetic fracture and aseptic loosening at 53 and 16 months, 12 metalwork removals and four ulnar nerve procedures. Posterolateral rotatory instability was present in one elbow, four had laxity and mild pain on loading (two with prosthesis or pin loosening), four had laxity associated with column fractures (two symptomatic) and 10 had asymptomatic mild laxity only. The triceps on approach had worse instability and clinical scores. Uncomplicated union occurred in all olecranon osteotomies and 86% of column fractures. One elbow had an incomplete cement mantle and seven had lucencies >1 mm; one was loose but acceptable. Five prostheses were in slight varus. Two elbows had early degenerative changes and 15 developed a medial spur on the trochlea. This is the largest reported experience of DHH. Early results of DHH show good outcomes after complex distal humeral fractures, despite a technically demanding procedure. Better results are obtained for treatment in the acute setting and with use of an olecranon osteotomy. As a result of this experience anatomical and clinical pre-requisites and advise on technique are outlined. An algorithm for use of DHH in relation to total elbow arthroplasty and ORIF for the treatment of complex intra-articular distal humeral fractures with or without column fractures is proposed

Introduction. The use of vascularised fibula grafts is an accepted method for reconstructing the distal femur following resection of malignant childhood tumours. Limitations relate to the mismatch of the cross-sectional area of the transplanted fibula graft and thel ocal bone, instability of the construct and union difficulties. We present midterm results of a unique staged technique—an immediate defect reconstruction using a double-barrel vascularised fibula graft set in in A-frame configuration and a subsequent intramedullary femoral lengthening. Materials & Methods. We retrospectively included 10 patients (mean age 10 y)with an osteosarcoma of the distal femur, who were treated ac-cording to the above-mentioned surgical technique. All patients were evaluated with regards to consolidation of the transplanted grafts, hypertrophy at the graft-host junctions, leg length discrepancies, lengthening indices, complications as well as functional outcome. Results. The mean defect size after tumour resection was 14.5 cm, the mean length of the harvested fibula graft 22 cm, resulting in a mean (acute) shortening of 4.7 cm (in 8 patients). Consolidation was achieved in all cases, 4 patients required supplementary bone grafting. Hypertrophy at the graft-host junctions was observed in78% of the evaluable junctions. In total 11 intramedullary lengthening procedures in 9 patients had been performed at the last follow up. The mean Muskuloskeletal Society Rating Scale(MSTS) score of the evaluable 9 patients was 85% (57% to 100%)with good or excellent results in 7 patients. Conclusions. A-frame vascularised fibula reconstructions showed encouraging results with respect to defect reconstruction, length as well as function and should therefore be considered a valuable option for reconstruction of the distal femur after osteosarcoma resection. The surgical implementation is demanding though, which is emphasized by the considerable high number of com-plications requiring surgical intervention, even though most were not serious

Tendon injuries after distal radius fractures Introduction: Tendon injuries after distal radius fractures are a well-documented complication that can occur in fractures managed both operatively and non-operatively. The extensor tendons, in particular the extensor pollicis longus (EPL) tendon, can be damaged and present late after initial management in a cast, or by long prominent screws that penetrate the dorsal cortex and cause attrition. Similarly, a prominent or distally placed volar plate can damage the flexor pollicis longus tendon (FPL). The aim of our study was to evaluate the incidence of tendon injuries associated with distal radius fractures. We conducted a single centre prospective observational study. Patients aged 18–99 who presented with a distal radius fracture between May 2018 to April 2020 were enrolled and followed-up for 24 months. Tendon injuries in the group were prospectively evaluated. Results: 199 patients with distal radius fractures were enrolled. 119 fractures (59.8%) had fixation and 80 (40.2%) were managed incast. In the non-operative group, 2 (2.5%) had EPL ruptures at approximately 4 weeks post injury. There were no extensor tendon ruptures in the operative group. In the operative group, there were 6 (5%) patients that required removal of metalware for FPL irritation. At the time of operation, there were no tendon ruptures noted. Within the operative group we evaluated plate prominence using a previously described classification (Soong et al.). 5 of the 6 patients (83%) with FPL irritation had Grade 3 prominence. The incidence of both flexor and extensor tendon injury in our cohort was 4%, extensor tendon rupture was 1% and flexor tendon rupture was avoided by early metalware removal. This study demonstrates tendon injuries are not uncommon after distal radius fractures, and close examination and follow-up are necessary to prevent eventual rupture. Plate prominence at the time of fixation should be minimised to reduce the risk of rupture

Purpose. The undulating pattern of the distal femur is well recognized. Radiographs do not always represent the full extent of the undulations. With recent increasing use of guided growth technique in the distal femur, it is important to define safe zones for screw placement. Method. We performed an anatomical study on 26 cadaveric distal femoral epiphyses, ages 3–18 years. High resolution three-dimensional surface scans were obtained with a laser scanner, and were analyzed to determine the absolute height of the central physeal ridge, and the central physeal ridge height with respect to the highest points medially and laterally. Results. The average height of the central physeal ridge was 5.5mm (range 2.9–9.8mm) with respect to the lowest point on the physis. When normalized to the size of the physis, both the height and surface area of the central physeal ridge decreased with increasing age. The amount that the central peak protruded superior to a line from the medial to lateral physeal edges is shown. In all specimens ages 13 years and older the central peak was below the medial-lateral line, in specimens ages 8–12 years it was no more than 4mm above the line, and in specimens under 8 years it was no more than 8mm above the line. Conclusion. The central physeal ridge is the major structure within the distal femoral physis. In patients 13 years and older the medial-lateral physeal line defines a safe zone one should stay above to avoid screw penetration into the central physis. In patients ages 8–12 years one should stay 4mm above the medial-lateral line, and in patients 8 years and under one should stay 8mm above the line

Dual plating of the medial and lateral distal femur has been proposed to reduce angular malunion and hardware failure secondary to delayed union or nonunion. This strategy improves the strength and alignment of the construct, but it may compromise the vascularity of the distal femur paradoxically impairing healing. This study investigates the effect of dual plating versus single plating on the perfusion of the distal femur. Ten matched pairs of fresh-frozen cadaveric lower extremities were assigned to either isolated lateral plating or dual plating of a single limb. The contralateral lower extremity was used as a matched control. A distal femoral locking plate was applied to the lateral side of ten legs using a standard sub-vastus approach. Five femurs had an additional 3.5mm reconstruction plate applied to the medial aspect of the distal femur using a medial sub-vastus approach. The superficial femoral artery and the profunda femoris were cannulated at the level of the femoral head. Gadolinium MRI contrast solution (3:1 gadolinium to saline ration) was injected through the arterial cannula. High resolution fat-suppressed 3D gradient echo sequences were completed both with and without gadolinium contrast. Intra-osseous contributions were quantified within a standardized region of interest (ROI) using customized IDL 6.4 software (Exelis, Boulder, CO). Perfusion of the distal femur was assessed in six different zones. The signal intensity on MRI was then quantified in the distal femur and comparison was made between the experimental plated limb and the contralateral, control limb. Following completion of the MRI protocol, the specimens were injected with latex medium and the extra-osseous vasculature was dissected. Quantitative MRI revealed that application of the lateral distal femoral locking plate reduced the perfusion of the distal femur by 21.7%. Within the dual plating group there was a reduction in perfusion by 24%. There was no significant difference in the perfusion between the isolated lateral plate and the dual plating groups. There were no regional differences in perfusion between the epiphyseal, metaphyseal or meta-diaphyseal regions. Specimen dissection in both plating groups revealed complete destruction of any periosteal vessels that ran underneath either the medial or lateral plates. Multiple small vessels enter the posterior condyles off both superior medial and lateral geniculate arteries and were preserved in all specimens. Furthermore, there was retrograde flow to the distal most aspect of the condyles medially and laterally via the inferior geniculate arteries. The medial vascular pedicle was proximal to the medial plate in all the dual plated specimens and was not disrupted by the medial sub-vastus approach in any specimens. Fixation of the distal femur via a lateral sub-vastus approach and application of a lateral locking plate results in a 21% reduction in perfusion to the distal femur. The addition of a medial 3.5mm reconstruction plate does not significantly compromise the vascularity of the distal femur. The majority of the vascular insult secondary to open reduction, internal fixation of the distal femur occurs with application of the lateral locking plate

Abstract. Introduction. We aimed to compare the outcomes of elderly patients with periarticular distal femur or supracondylar periprosthetic fractures treated with either open reduction internal fixation or distal femoral replacement. Methods. A retrospective review of patients over 65 years with AO Type B and C fractures of the distal femur or Su type I and II periprosthetic fractures treated with either a DFR or ORIF was undertaken. Outcomes including Length of Stay, PROMs (Oxford Knee Score and EQ 5D), infection, union, mortality, complication and reoperation rates were assessed. Data on confounding variables were also collected for multivariate analysis. Patients below 65 years and extra articular fractures were excluded. Results. 23 patients (11 in DFR group and 12 in ORIF group) fulfilled inclusion criteria and were included in the analysis. There was no difference between the DFR and ORIF groups with respect to SDI, demographic variables, ASA grade, FCI, preoperative Hb and renal function. There was no difference in 30 day mortality, reoperation rates, 30 day readmission rates and LOS between the two groups. Mean follow up was 12.7 and 15.9 months respectively in the DFR and ORIF groups. At final follow up after accounting for all confounding variables on multivariate analysis, functional outcomes using OKS (adjusted mean: 29.5 vs 15.8) and Health related Quality of Life outcomes using EQ 5D (adjusted mean: 0.453 vs −0.07) were significantly better in the DFR group. Conclusion. DFR for periarticular and periprosthetic distal femoral fractures in the elderly are associated with better patient reported outcomes

The purpose of this study is to evaluate risk factors for distal construct failure (DCF) in posterior spinal instrumented fusion (PSIF) in adolescent idiopathic scoliosis (AIS). We observed an increased rate of DCF when the pedicle screw in the lowest instrumented vertebra (LIV) was not parallel to the superior endplate of the LIV, however this has not been well studied in the literature. We hypothesise a more inferiorly angled LIV screw predisposes to failure and aim to find the critical angle that predisposes to failure. A retrospective cohort study was performed on all patients who underwent PSIF for AIS at the Starship Hospital spine unit from 2010 to 2020. On a lateral radiograph, the angle between the superior endplate of the LIV was measured against its pedicle screw trajectory. Data on demographics, Cobb angle, Lenke classification, instrumentation density, rod protrusion from the most inferior screw, implants and reasons for revision were collected. Of 256 patients, 10.9% (28) required at least one revision. The rate of DCF was 4.6% of all cases (12 of 260) and 25.7% of revisions were due to DCF. The mean trajectory angle of DCF patients compared to all others was 13.3° (95%CI 9.2° to 17.4°) vs 7.6° (7° to 8.2°), p=0.0002. The critical angle established is 11°, p=0.0076. Lenke 5 and C curves, lower preoperative Cobb angle, titanium only rod constructs and one surgeon had higher failure rates than their counterparts. 9.6% of rods protruding less than 3mm from its distal screw disengaged. We conclude excessive inferior trajectory of the LIV screw increases the rate of DCF and a screw trajectory greater than 11° predisposes to failure. This is one factor that can be controlled by the surgeon intraoperatively and by avoiding malposition of the LIV screw, a quarter of revisions can potentially be eliminated

Introduction. Intra articular distal tibia fractures can lead to post-traumatic osteoarthritis. Joint distraction has shown promise in elective cases. However, its application in acute fractures remains unexplored. This pilot study aims to fill this knowledge gap by investigating the benefits of joint distraction in acute fractures. Materials & Methods. We undertook a restrospective cohort study comprising patients with intra-articular distal tibia and pilon fractures treated with a circular ring fixator (CRF) at a single center. Prospective data collection included radiological assessments, Patient-Reported Outcome Measures (PROM), necessity for additional procedures, and Kellgren and Lawrence grade (KL) for osteoarthritis (OA). 137 patients were included in the study, 30 in the distraction group and 107 in the non-distraction group. There was no significant difference between the groups. Results. Mean follow-up was 3.73 years. There was no significant difference between the groups in overall complications or need for further procedures. There was no significant difference in progression of KL between the groups (1.81 vs 2.0, p=0.38) mean follow up 1.90 years. PROM data was available for 44 patients (6 distraction, 38 non-distraction) with a mean follow-up of 1.71 years. There was no significant difference in EQ5D (p=0.32) and C Olerud-H Molander scores (p=0.17). Conclusions. This pilot study suggests that joint distraction is safe in the acute setting. However, the study's impact is constrained by a relatively small patient cohort and a short-term follow-up period. Future investigations should prioritise longer-term follow-ups and involve a larger patient population to more comprehensively evaluate the potential benefits of joint distraction in acute fractures

The Adams-Berger reconstruction is an effective technique for treating distal radioulnar joint (DRUJ) instability. Graft preparation techniques vary amongst surgeons with insufficient evidence to support one technique over another. Our study evaluated the biomechanical properties of four graft preparation techniques. Extensor tendons were harvested from fresh frozen porcine trotters obtained from a local butcher shop and prepared in one of three configurations (n=5 per group): tendon only; tendon prepared with non-locking, running suture (2-0 FiberLoop, Arthrex, Naples, FL) spaced at 6 mm intervals; and tendon prepared with suture spaced at 12 mm intervals. A fourth configuration of suture alone was also tested. Tendons were allocated in a manner to ensure comparable average diameters amongst groups. Biomechanical testing occurred using custom jigs simulating radial and ulnar tunnels attached to a Bose Electroforce 3510 mechanical testing machine (TA Instruments). After being woven through the jigs, all tendons were sutured end-to-end with 2-0 PROLENE suture (Ethicon). Tendons then underwent a staircase cyclic loading protocol (5-25 Newtons [N] at 1 hertz [Hz] for 1000 cycles, then 5-50 N at 1 Hz for 1000 cycles, then 5-75 N at 1 Hz for 1000 cycles) until graft failure; if samples did not fail during the protocol, they were then loaded to failure. Samples were visually inspected for mode of failure after the protocol. A one-way analysis of variance was used to compare average tendon diameter; post-hac Tuhey tests were used to compare elongation and elongation rate. Survival to cyclic loading was analyzed using Kaplan-Meier survival curves with log rank. Statistical significance was set at a = 0.05. The average tendon diameter of each group was not statistically different [4.17 mm (tendon only), 4.33 mm (FiberLoop spaced 6 mm), and 4.30 mm (FiberLoop spaced 12 mm)]. The average survival of tendon augmented with FiberLoop was significantly higher than tendon only, and all groups had significantly improved survival compared to suture only. There was no difference in survival between FiberLoop spaced 6 mm and 12 mm. Elongation was significantly lower with suture compared to tendon augmented with FiberLoop spaced 6 mm. Elongation rate was significantly lower with suture compared to all groups. Modes of failure included rupture of the tendon, suture, or both at the simulated bone and suture and/or tendon interface, and elongation of the entire construct without rupture. In this biomechanical study, augmentation of porcine tendons with FiberLoop suture spaced at either 6 or 12 mm for DRUJ reconstruction significantly increased survival to a staircase cyclic loading protocol, as suture material was significantly stiffer than any of the tendon graft configurations

The aim of this study was to determine the floor and ceiling effects for both the QuickDASH and PRWE following a fracture of the distal radius. Secondary aims were to determine the degree to which patients with a floor or ceiling effect felt that their wrist was ‘normal’, and if there were patient factors associated with achieving a floor or ceiling effect. A retrospective cohort study of patients sustaining a distal radius fracture and managed at the study centre during a single year was undertaken. Outcome measures included the QuickDASH, the PRWE, EuroQol-5 Dimension-3 Levels (EQ-5D-3L), and the normal wrist score. There were 526 patients with a mean age of 65yrs (20–95) and 421 (77%) were female. Most patients were managed non-operatively (73%, n=385). The mean follow-up was 4.8yrs (4.3–5.5). A ceiling effect was observed for both the QuickDASH (22.3%) and PRWE (28.5%). When defined to be within the minimum clinical important difference of the best available score, the ceiling effect increased to 62.8% for the QuickDASH and 60% for the PRWE. Patients that achieved a ceiling score for the QuickDASH and PRWE subjectively felt their wrist was only 91% and 92% normal, respectively. On logistic regression analysis, a dominant hand injury and better health-related quality of life were the common factors associated with achieving a ceiling score for both the QuickDASH and PRWE (all p<0.05). The QuickDASH and PRWE demonstrate ceiling effects when used to assess the outcome of fractures of the distal radius. Patients achieving ceiling scores did not consider their wrist to be ‘normal’. Future patient-reported outcome assessment tools for fractures of the distal radius should aim to limit the ceiling effect, especially for individuals or groups that are more likely to achieve a ceiling score

Introduction. Coronal malalignment and leg length discrepancies (LLD) are frequently associated. Temporary hemiepiphysiodesis (tHED) is commonly employed for the correction of limb malalignment in skeletally immature patients. For treatment of LLD greater than 2 cm, lengthening with intramedullary legnthening nails is a safe and reliable technique. However, the combined application of these approaches in skeletally immature patients has not yet been investigated. Materials & Methods. Retrospective radiological and clinical analysis of 25 patients (14 females, 11 males) who underwent intramedullary femoral lengthening with an antegrade PRECICE® lengthening nail as well as tHED of the distal femur and / or proximal tibia between 2014 and 2019. tHED was conducted by implantation of flexible staples (FlexTack™) either prior (n = 11), simultaneously (n = 10), or subsequently (n = 4) to femoral lengthening. The mean follow-up period was 3.7 years (±1.4). Results. The median initial LLD was 39.0 mm (35.0–45.0). 21 patients (84%) presented valgus and 4 (16%) showed varus malalignment. Leg length equalization was achieved in 13 patients at skeletal maturity (62%). The median LLD of patients with a residual LLD > 10 mm was 15.5 mm (12.8–21.8). Limb realignment was obtained in nine of seventeen skeletally mature patients (53%) in the valgus group, and in one of four patients (25%) in the varus group. Conclusions. The combination of antegrade femoral lengthening and tHED can efficiently correct LLD and coronal limb malalignment in skeletally immature patients. Nevertheless, achieving limb length equalization and realignment may render difficult in cases of severe LLD and angular deformity. Furthermore, the reported techniques ought to be thoroughly planned and executed and require regular clinical and radiological examinations until skeletal maturity to avoid - or timely detect and manage - adverse events such as overcorrection and rebound of deformity

Aims/Hypothesis. The aims of this study were: 1) to quantitatively analyse the amount of knee extension that is achieved with +2mm incremental increases in the amount of distal femoral bone that is resected during TKA in the setting of a flexion contracture, 2) to quantify the amount of coronal plane laxity that occurs with each 2mm increase in the amount of distal femur resected. In the setting of a soft tissue flexion contracture, we hypothesized that although resecting more distal femur will reliably improve maximal knee extension, it will ultimately lead to increased varus and/or valgus laxity throughout mid-flexion. Methods. Seven fresh-frozen cadaver legs from hip-to-toe underwent TKA with a posterior stabilized implant using a measured resection technique with computer navigation system equipped with a robotic cutting-guide, in this IRB approved, controlled laboratory study. After the initial tibial and femoral resections were performed, the posterior joint capsule was sutured (imbricated) through the joint space under direct visualization until a 10° flexion contracture was obtained with the trial components in place, as confirmed by computer navigation. Two distal femoral recuts of +2mm each where then subsequently made and after the remaining femoral cuts were made, the trail implants were reinserted. The navigation system was used to measure overall coronal plane laxity by measuring the mechanical alignment angle at maximum extension, 30°, 60° and 90° of flexion, when applying a standardized varus/valgus load of 9.8 [Nm] across the knee using a 4kg spring-load located at 25cm distal to the knee joint line.(Figure 1) Coronal plane laxity was defined as the absolute difference (in °) between the mean mechanical alignment angle obtained from applying a standardized varus and valgus stress at 0°, 30, 60° and 90°. Each measurement was performed three separate times and averaged. The maximal extension angle achieved following each 2mm distal recut was also recorded. Two-tailed student's t-tests were performed to analyze whether there was difference in the mean laxity at each angle and if there was a significant improvement in maximal extension with each recut. P-values < 0.05 were considered significant. Results. For a 10° flexion contracture, performing the first distal recut of +2mm increased overall coronal-plane instability by approximately 3° at 30° and 60° of flexion (p < 0.05).(Figure 2) Performing the second recut of +4mm further increased mid-flexion instability by another 2° (p < 0.01).(Figure 2) Maximum extension increased from 10° of flexion to 6.4° (±2.5° SD, p < 0.005) and to 1.4° (±1.8° SD, p < 0.001) of flexion with each 2mm recut of the distal femur. Conclusions. Using a reliable, accurate, and reproducible method of measuring coronal plane laxity and maximal knee extension, we have shown that in the setting of a flexion contracture or tight extension space during TKA, recutting the distal femur by 2 mm will effectively increase the amount of maximal extension by 4°; however, as a secondary effect, recutting the distal femur by 2 mm will also lead to 2.5° of increased coronal plane laxity in midflexion

Distal femur fractures (DFF) are common, especially in the elderly and high energy trauma patients. Lateral locked osteosynthesis constructs have been widely used, however non-union and implant failures are not uncommon. Recent literature advocates for the liberal use of supplemental medial plating to augment lateral locked constructs. However, there is a lack of proprietary medial plate options, with some authors supporting the use of repurposing expensive anatomic pre-contoured plates. The aim of this study was to investigate the feasibility of a readily available cost-effective medial implant option. A retrospective analysis from January 2014 to June 2022 was performed on DFF (primary or revision) managed with supplemental medial plating with a Large Fragment Locking Compression Plate (LCP) T-Plate (~$240 AUD) via a medial sub-vastus approach. The T-plate was contoured and placed superior to the medial condyle. A combination of 4.5mm cortical, 5mm locking and/or 6.5mm cancellous screws were used, with oblique screw trajectories towards the distal lateral cortex of the lateral condyle. All extra-articular fractures and revision fixation cases were allowed to weight bear immediately. The primary outcome was union rate. This technique was utilised on sixteen patients; 3 acute, 13 revisions; mean age 52 years (range 16-85), 81% male, 5 open fractures. The union rate was 100%, with a median time to union of 29 weeks (IQR 18-46). The mean follow-up was 15 months. There were two complications: a deep infection requiring two debridements and a prominent screw requiring removal. The mean range of motion was 1–108. o. . Supplemental medial plating of DFF with a Large Fragment LCP T-Plate is a feasible, safe, and economical option for both acute fixation and revisions. Further validation on a larger scale is warranted, along with considerations to developing a specific implant in line with these principles

Introduction. Distal femur fractures have traditionally been stabilized with either lateral locking plate or retrograde intramedullary nail. Dual-plates and nail-plate combination fixation have the theoretical biomechanical advantage, faster union and allows patients to weight bear immediately. The aim of this study is to compare single vs combination fixation, and evaluate outcomes and complications. Method. We retrospectively reviewed all patients over 60, admitted to Christchurch Hospital, between 1st Jan 2016 and 31st Dec 2022, with an AO 33A/33B/33C distal femur fracture. Patient demographics, fracture characteristics, operation details, and follow up data were recorded. Primary outcomes are union rate, ambulatory status at discharge, and surgical complications. Secondary outcomes include quality of reduction, operation time and rate of blood transfusions. Results. 114 patients were included. (92 single fixation, 22 combination fixation). Baseline demographic data and fracture characteristics did not differ between the cohorts. There was no difference in the rate of union or time to union between the two cohorts. Combination fixation patients were allowed to weight-bear as tolerated significantly more than single fixation patients (50% vs 18.9%, p=0.003). There was no difference in length of hospital stay, transfusion, complication and mortality rates. Medial translation of the distal articular block was significantly lower in the combination fixation cohort (1.2% vs 3.4%, p=0.021). Operation time was significantly longer in the combination fixation cohort (183mins vs 134mins, p<0.001). Discussion. The results show no difference in achieving union or time to union, despite better quality of fracture reduction with dual fixation. This differs to previously published literature. The clear benefit of combination fixation is immediate weight-bearing. As expected, operation times were longer with combination fixation, however this did not translate to more complications. Conclusion. Combination fixation allows earlier weight bearing, at the cost of longer operation times

Premature growth arrests are an infrequent, yet a significant complication of physeal fractures of the distal radius in children and adolescents. Through early diagnosis, it is possible to prevent clinical repercussions of the anatomical and biomechanical alterations of the wrist. Their true incidence has not been well established, and there exists no consensual systematic monitoring plan for minimising its impacts. The main objective was to evaluate the prevalence of growth arrests after a physeal distal radius fracture. The secondary objective was to identify risk factors in order to better guide clinicians for a systematic follow-up. All patients seen between 2014–2016 in a tertiary orthopaedic clinic were retrospectively reviewed. Inclusion criteria were (one) a physeal fracture of the distal radius (two) adequate clinical/radiological follow-up. Descriptive, Chi-square and binary logistic regression analyses were carried out using SPSS software. One hundred ninety patients (mean age: 12 ± 2.8 years) fulfilled the inclusion criteria. Forty percent (n=76) of the fractures were treated by closed reduction. Premature growth arrest was seen in 6.8% (n=13) and diagnosed at a mean of 10 months post trauma. The logistic regression showed that the initial translation percentage (>30%) (p 25) (p increase the risk of growth arrest. After adjusting for concomitant ipsilateral ulnar injuries, a positive association between physeal complications and fracture manipulation was detected (76.9%, p=0.03). A non-significant trend between premature growth arrest and associated ulnar injury was observed (p=0.054). No association was identified for trauma velocity, fracture type, gender and age, and growth complications. A prevalence of 6.8% of growth arrest was found after a physeal fracture of the distal radius. Fractures presenting with an initial coronal translation > 30% and/or angulation > 25 from normal, as well as those treated by manipulation, have been shown to be at risk for a premature growth arrest of the distal radius. This study highlights the importance of a systematic follow-up after a physeal fracture of the distal radius especially for patients with a more displaced fracture who had a closed reduction performed. An optimal follow-up period should be over 10 months to optimize the detection of growth arrest and treat it promptly, thereby minimizing negative clinical consequences

Introduction. Surgeons commonly resect additional distal femur during primary total knee arthroplasty (TKA) to correct a flexion contracture to restore range of motion and knee function. However, the effect of joint line elevation on the resulting TKA kinematics including frontal plane laxity is unclear. Thus, our goal was to quantify the effect of additional distal femoral resection on passive extension and mid-flexion laxity. Methods. Six computational knee models with capsular and collateral ligament properties specific to TKA were developed and implanted with a contemporary posterior-stabilized TKA. A 10° flexion contracture was modeled by imposing capsular contracture as determined by simulating a common clinical exam of knee extension and accounting for the length and weight of each limb segment from which the models were derived (Figure 1). Distal femoral resections of 2 mm and 4 mm were simulated for each model. The knees were then extended by applying the measured knee moments to quantify the amount of knee extension. The output data were compared with a previous cadaveric study using a two-sample two-tailed t-test (p<0.05) [1]. Subsequently, varus and valgus torques of ±10 Nm were applied as the knee was flexed from 0° to 90° at the baseline, and after distal resections of 2 mm, and 4 mm. Coronal laxity, defined as the sum of varus and valgus angulation in response to the applied varus and valgus torques, was measured at 30° and 45°of flexion, and the flexion angle was identified where the increase in laxity was the greatest with respect to baseline. Results. With 2 mm and 4 mm of distal femoral resection, the knee extended an additional 4°±0.5° and 8°±0.75°, respectively (Figure 2). No significant difference was found between the extension angle predicted by the six models and the results of the cadaveric study after 2 mm (p= 0.71) and 4 mm (p= 0.47). At 2 mm resection, mean coronal laxity increased by 3.1° and 2.7° at 30° and 45°of flexion, respectively. At 4 mm resection, mean coronal laxity increased by 6.5° and 5.5° at 30° and 45° of flexion, respectively (Figures 3a and 3b). The flexion angle corresponding to the greatest increase in coronal laxity for 2 mm of distal resection occurred at 22±7° of flexion with a mean increase in laxity of 4.0° from baseline. For 4 mm distal resection, the greatest increase in coronal laxity occurred at 16±6° of flexion with a mean increase in laxity of 7.8° from baseline. Conclusion. A TKA computational model representing a knee with preoperative flexion contracture was developed and corroborated measures from a previous cadaveric study [1]. While additional distal femoral resection in primary TKA increases passive knee extension, the consequent joint line elevation induced up to 8° of additional coronal laxity in mid-flexion. This additional midflexion laxity could contribute to midflexion instability; a condition that may require TKA revision surgery. Further studies are warranted to understand the relationship between joint line elevation, midflexion laxity, and instability. For any figures or tables, please contact the authors directly

The extracortical single-button (SB) inlay repair is one of the most preferred distal biceps tendon repair techniques. However, specific complications such as neurovascular injury and non-anatomic repairs have led to the development of techniques that utilize intracortical double-button (DB) fixation. To compare the biomechanical stability of the extracortical SB repair with the anatomical DB repair technique. Controlled laboratory study. The distal biceps tendon was transected in 18 cadaveric elbows from 9 donors. One elbow of each donor was randomly assigned to the extracortical SBor anatomical DB group. Both groups were cyclically loaded with 60N over 1000 cycles between 90° of flexion and full extension. The elbow was then fixed in 90° of flexion and the repair construct loaded to failure. Gap-formation and construct stiffness during cyclic loading, and ultimate load to failure was analysed. After 1000 cycles, the anatomical DB technique compared with the extracortical SB technique showed significantly less gap-formation (mean difference 1.2 mm; p=0.017) and significantly more construct stiffness (mean difference 31 N/mm; p=0.023). Ultimate load to failure was not significantly different comparing both groups (SB, 277 N ±92 vs. DB, 285 N ±135; p=0.859). The failure mode in the anatomical DB group was significantly different compared with the extracortical SB technique (p=0.002) and was due to fracture avulsion of the BicepsButton in 7 out of 9 specimens (vs. none in SB group). Our study shows that the intracortical DB technique produces equivalent or superior biomechanical performance to the SB technique. The DB repair technique reduces the risk of nerve injury and better restores the anatomical footprint of biceps tendon. The DB technique may offer a clinically viable alternative to the SB repair technique