Hamstring muscle strain is a common sports related injury. It has been reported in a variety of sports, following acceleration or deceleration while running or jumping. Injury may vary from simple muscle strains to partial or complete rupture of the hamstring origin. Avulsion fracture of the ischial tuberosity has also been described. Simple hamstring muscle strains are treated conservatively. Surgical exploration and repair is currently advocated for partial or complete rupture of the hamstring origin. A few case series exists in literature suggesting the benefits of early intervention. We report a series of 8 athletes who presented between 2002 and 2006 with complete tear of their hamstring origin. Avulsion of the ischial tuberosity was excluded in these cases. After confirming the diagnosis, early surgical exploration and repair or reattachment was performed. The patients were braced for 8 weeks. This was followed by specialist physiotherapy and a supervised rehabilitation programme over 6 months. All patients were followed up to monitor return to normal activities and sports. The sciatic nerve was scarred to the avulsed tendon in three cases. Neurolysis led to a rapid relief of symptoms. Cases where the hamstring origin had retracted more than 3 cm required a figure 7 incision. There were no major complications including nerve palsies. An excellent functional outcome was noted by 12 months in all 8 patients. 7 of them returned to their previous level within 6-9 months of injury. One person despite a very good recovery, opted out of sports. No other complications were seen as a result of the surgical procedure. In conclusion, a tear of the origin of hamstring muscles is a significant injury. Early surgical repair and physiotherapy is associated with a good outcome and enables an early return to high level sports

Pain and disability following wrist trauma are highly prevalent, however the mechanisms underlying painare highly unknown. Recent studies in the knee have demonstrated that altered joint contact may induce changes to the subchondral bone density and associated pain following trauma, due to the vascularity of the subchondral bone. In order to examine these changes, a depth-specific imaging technique using quantitative computed tomography (QCT) has been used. We've demonstrated the utility of QCT in measuring vBMD according to static jointcontact and found differences invBMD between healthy and previously injured wrists. However, analyzing a static joint in a neutral position is not necessarily indicative of higher or lower vBMD. Therefore, the purposeof this study is to explore the relationship between subchondral vBMDand kinematic joint contact using the same imaging technique.

To demonstrate the relationship between kinematic joint contact and subchondral vBMDusing QCT, we analyzed the wrists of n = 10 participants (n = 5 healthy and n = 5 with previous wrist trauma). Participantsunderwent 4DCT scans while performing flexion to extension to estimate radiocarpal (specifically the radiolunate (RL) and radioscaphoid (RS)) joint contact area (JCa) between the articulating surfaces. The participantsalso underwent a static CT scan accompanied by a calibration phantom with known material densities that was used to estimate subchondral vBMDof the distal radius. Joint contact is measured by calculatinginter-bone distances (mm2) using a previously validated algorithm. Subchondral vBMD is presented using mean vBMD (mg/K2HPO4) at three normalized depths from the subchondral surface (0 to 2.5, 2.5 to 5 and 5 to 7.5 mm) of the distal radius.

The participants in the healthy cohort demonstrated a larger JCa in the RS joint during both extension and flexion, while the trauma cohort demonstrated a larger JCa in the RL during extension and flexion. With regards to vBMD, the healthy cohort demonstrated a higher vBMD for all three normalized depths from the subchondral surface when compared to the trauma cohort.

Results from our preliminary analysis demonstrate that in the RL joint specifically, a larger JCa throughout flexion and extension was associated with an overall lower vBMD across all three normalized layers. Potential reasoning behind this association could be that following wrist trauma, altered joint contact mechanics due to pathological changes (for example, musculoskeletal trauma), has led to overloading in the RL region. The overloading on this specific region may have led to a decrease in the underlying vBMD when compared to a healthy wrist. However, we are unable to conclude if this is a momentary decrease in vBMD that could be associated with the acute healing phase following trauma given that our analysis is cross-sectional. Therefore, future work should aim to analyze kinematic JCa and vBMD longitudinally to better understand how changes in kinematic JCa over time, and how the healing process following wrist trauma, impacts the underlying subchondral bone in the acute and longitudinal phases of recovery.

Aims. The principles of evidence-based medicine (EBM) are the foundation of modern medical practice. Surgeons are familiar with the commonly used statistical techniques to test hypotheses, summarize findings, and provide answers within a specified range of probability. Based on this knowledge, they are able to critically evaluate research before deciding whether or not to adopt the findings into practice. Recently, there has been an increased use of artificial intelligence (AI) to analyze information and derive findings in orthopaedic research. These techniques use a set of statistical tools that are increasingly complex and may be unfamiliar to the orthopaedic surgeon. It is unclear if this shift towards less familiar techniques is widely accepted in the orthopaedic community. This study aimed to provide an exploration of understanding and acceptance of AI use in research among orthopaedic surgeons. Methods. Semi-structured in-depth interviews were carried out on a sample of 12 orthopaedic surgeons. Inductive thematic analysis was used to identify key themes. Results. The four intersecting themes identified were: 1) validity in traditional research, 2) confusion around the definition of AI, 3) an inability to validate AI research, and 4) cautious optimism about AI research. Underpinning these themes is the notion of a validity heuristic that is strongly rooted in traditional research teaching and embedded in medical and surgical training. Conclusion. Research involving AI sometimes challenges the accepted traditional evidence-based framework. This can give rise to confusion among orthopaedic surgeons, who may be unable to confidently validate findings. In our study, the impact of this was mediated by cautious optimism based on an ingrained validity heuristic that orthopaedic surgeons develop through their medical training. Adding to this, the integration of AI into everyday life works to reduce suspicion and aid acceptance. Cite this article: Bone Jt Open 2023;4(9):696–703

The rate of arterial injury in trauma patients with pelvic ring fractures has been cited as high as 15%. Addressing this source of hemorrhage is essential in the management of these patients as mortality rates are reported as 50%. Percutaneous techniques to control arterial bleeding, such as embolization and REBOA, are being employed with increasing frequency due to their assumed lower morbidity and invasiveness than open exploration or cross clamping of the aorta. There are promising results with regards to the mortality benefits of angioembolization. However, there are concerns with regards to morbidity associated with embolization of the internal iliac vessels and its branches including surgical wound infection, gluteal muscle necrosis, nerve injury, bowel infarction, and thigh / buttock claudication. The primary aim of this study is to determine whether pelvic arterial embolization is associated with surgical site infection (SSI) in trauma patients undergoing pelvic ring fixation. This observational cohort study was conducted using US trauma registry data from the American College of Surgeons (ACS) National Trauma Database for the year of 2018. Patients over the age of 18 who were transported through emergency health services to an ACS Level 1 or 2 trauma hospital and sustained a pelvic ring fracture treated with surgical fixation were included. Patients who were transferred between facilities, presented to the emergency department with no signs of life, presented with isolated penetrating trauma, and pregnant patients were excluded from the study. The primary study outcome was surgical site infection. Multivariable logistic regression was performed to estimate treatment effects of angioembolization of pelvic vessels on surgical site infection, adjusting for known risk factors for infection. Study analysis included 6562 trauma patients, of which 508 (7.7%) of patients underwent pelvic angioembolization. Overall, 148 (2.2%) of patients had a surgical site infection, with a higher risk (7.1%) in patients undergoing angioembolization (unadjusted odds ratio (OR) 4.0; 95% CI 2.7, 6.0; p < 0 .0001). Controlling for potential confounding, including patient demographics, vitals on hospital arrival, open fracture, ISS, and select patient comorbidities, pelvic angioembolization was still significantly associated with increased odds for surgical site infection (adjusted OR 2.0; 95% CI 1.3, 3.2; p=0.003). This study demonstrates that trauma patients who undergo pelvic angioembolization and operative fixation of pelvic ring injuries have a higher surgical site infection risk. As the use of percutaneous hemorrhage control techniques increase, it is important to remain judicious in patient selection

Aim. The rise of multidrug-resistant bacteria and the decreasing efficacy of antibiotic therapy in successfully treating biofilm-associated infections are prompting the exploration of alternative treatment options. This study investigates the efficacy of different bioactive glass (BAG) formulations - alone or combined with vancomycin - to eradicate biofilm. Further, we study the influence of BAG on pH and osmotic pressure as important factors limiting bacterial growth. Method. Different BAG-S53P4 formulations were used for this study, including (a) BAG-powder (<45 μm), (b) BAG-granules (500–800 μm), (c) a cone-shaped BAG-scaffold and (d) two kinds of BAG-putty containing granules, with no powder (putty-A) or with additional powder (putty-B), and a synthetic binder. Inert glass beads were included as control. All formulations were tested in a concentration of 1750 g/ml in Müller-Hinton-Broth. Targeted bacteria included methicillin-resistant Staphylococcus aureus (MRSA) and epidermidis (MRSE). Vancomycin was tested at the minimum-inhibitory-concentration for each strain (1 µg/ml for MRSA; 2 μg/ml for MRSE). To investigate the antibiofilm effect of BAG alone or combined with vancomycin, 3 hour-old MRSA or MRSE biofilms were formed on porous glass beads and exposed to BAG ± vancomycin for 24h, 72h and 168h. After co-incubation, biofilm-beads were deep-washed in phosphate-buffered saline and placed in glass vials containing fresh medium. Recovering biofilm bacteria were detected by measuring growth-related heat production at 37°C for 24h by isothermal microcalorimetry. Changes in pH and osmotic pressure over time were assessed after co-incubation of each BAG formulation in Müller-Hinton-Broth for 0h, 24h, 72h and 168h. Results. All BAG formulations showed antibiofilm activity against MRSA and MRSE in a time-dependent manner, where longer incubation times revealed higher antibiofilm activity. BAG-powder and BAG-putty-B were the most effective formulations suppressing biofilm, followed by BAG-granules, BAG-scaffold and finally BAG-putty-A. The addition of vancomycin had no substantial impact on biofilm suppression. An increase in pH and osmotic pressure over time could be observed for all BAG formulations. BAG-powder reached the highest pH value of 12.5, whereas BAG-putty-A resulted in the lowest pH of 9. Both BAG-putty formulations displayed the greatest increase on osmotic pressure. Conclusions. BAG-S53P4 has demonstrated efficient biofilm suppression against MRSA and MRSE, especially in powder-containing formulations. Our data indicates no additional antibiofilm improvement with addition of vancomycin. Moreover, high pH appears to have a larger antimicrobial impact than high osmolarity. Acknowledgements. This work was supported by PRO-IMPLANT Foundation (Berlin, Germany). The tested materials were provided by Bonalive Biomaterials Ltd (Turku, Finland)

Aim. Extraspinal osteoarticular tuberculosis (TOA-ER) is a rare form of extra-pulmonary tuberculosis. It remains a topical problem not only in underdeveloped countries but also in developed countries due to cases of immune deficiency. Through a study of 40 cases, we specify the current diagnostic aspects of TOA-ER and detail their therapeutic and evolutionary modalities. Method. The mean age of our patients was 40 years with a clear predominance of females observed (SR = 0.66). 76.31% of the cases were from a rural setting. The impairment was single-focal in 72.5%. Associated tuberculosis location was found in 59% of cases. Pain and swelling were the main clinical symptoms. Signs of tuberculous impregnation were found in less than half of the cases. The IDR was positive in 67%. All patients underwent an appropriate radiological exploration consisting of a standard x-ray (30 cases), CT (21 cases) and MRI (23 cases). technetium-99m bone scintigraphy, performed in 15 cases, detected 5 infra-clinical osteoarticular locations. 77.5% of patients had formal pathological and / or bacteriological confirmation of the diagnosis. All patients had adequate anti-tuberculosis chemotherapy with a mean duration of 18 months. 67% of patients had a surgical debridement procedure. Results. After a mean follow-up of 5 years, the outcome was favourable in 75.2% of cases. A microbiological cure at the cost of serious functional sequelae was noted in 12.8% of cases. The outcome was unfavourable with relapse observed in 4.8% of cases and death in 7.2% of cases. Conclusions. Extraspinal osteoarticular tuberculosis is a fairly common condition in our country. Its insidious clinical course is the cause of diagnostic and therapeutic delay. Its treatment is mainly medical. The surgery keeps some indications. Good therapeutic adherence and early diagnosis are the best guarantees of good therapeutic results

Sciatic nerve injury remains a significant and devastating complication of total hip arthroplasty. Incidence as quoted in the literature ranges from 0.08% in primary joint replacement to 7.5% in revision arthroplasty. While as urgent exploration is recommended for nerve palsies associated with pain, management of sciatic nerve palsy with little or no pain is still controversial. In light of this, many patients with persistent palsies are often not referred to our specialist centre until after 6 months post-injury. The aim of this study was to review the outcomes of surgical intervention in patients presenting with sciatic nerve palsy more than 6 months after total hip arthroplasty. This retrospective cohort study identified 35 patients who underwent exploration and neurolysis of the affected sciatic nerve. All patients had documented follow-up at 1, 3, 6, 12 and 18 months to assess sensory and motor recovery. Patients were scored for sensory and motor function in the tibia and common personal nerve divisions, pre and post-operatively. The scoring system devised by Kline et al (1995) was used. Pre-operative electrophysiology was also reviewed. We found a statistically significant functional recovery following neurolysis of the sciatic nerve (p<0.01). A statistically significant relationship was also found between time to neurolysis and recovery of tibial nerve function (p = 0.02), such that greater delay to neurolysis was associated with poorer recovery. There was no significant relationship between time to neurolysis and recovery of common peroneal nerve function (p = 0.28). Our results indicate that the neurolysis of the sciatic nerve, six months or more post injury is associated with functional recovery. We feel that without surgical exploration this clinical improvement would not have occurred. Therefore, we believe that neurolysis plays a vital role at any stage of sciatic nerve injury. However, early presentation to a specialist unit is associated with better outcomes

Analysis of orthopaedic malpractice claims has shown that highest impact allegations (highest payment dollars per claim) were those that were related to failure to protect anatomic structures in surgical fields. The prevalence of subclinical peripheral neurologic deficit following reverse and anatomic shoulder arthroplasty has been reported to be 47% and 4%, respectively. We propose the following five rules in order to avoid neurovascular injury during shoulder arthroplasty cases:. Pre-operative planning would assure a smooth operation without intra-operative difficulties. Adequate planning would include appropriate imaging, obtaining previous operative reports, complete pre-operative neurovascular examination and requesting the necessary operative equipment. Tug test: It is crucial to palpate the axillary nerve and be aware of its location. The tug test is a systematic technique for locating and protecting the axillary nerve. Neuromonitoring has been utilised in shoulder surgery in the past. Nagda et al showed that nerve alerts during shoulder arthroplasty occurred 56.7% of the time and 50% of the events were with the arm in abduction, external rotation and extension; 76.7% of signals returned to normal with retractor removal and change in arm positioning. We recommend removing all retractors and returning the arm to neutral position several times during surgery, especially during the glenoid exposure when the arm is in abduction and external rotation. Newer commercially available nerve stimulators are extremely useful in locating and protecting neurovascular structures. We recommend brachial plexus exploration and axillary nerve dissection with the aid of a nerve stimulator in all revision cases. Availability of a nerve/microvascular surgeon as an assistant in revision cases for brachial plexus exploration using a microscope is crucial for successful revision surgery

Supracondylar fractures of the humerus (SCH) are the most common fractures sustained following a fall among children. The majority of these fractures are mild, but the most severe injury types can result in a disruption to the nerves and blood supply resulting in limb threatening injuries and potential life-long disability. Better understanding of mechanisms of injury and child-related factors that influence injury, especially for severe cases, is crucial to identifying best practices and informing policy. We aim to stratify fractures and examine the associated mechanisms and circumstances of injury to identify best practices and inform supportive policy. In doing so, we plan to investigate why some children sustain more severe fractures than others by exploring mechanisms and locations of injury, and risk-taking behaviours. A prospective, mixed-methods pilot study employing a child-led research design. Our approach links narratives from qualitative photo elicitation interviews (PEI) to mapped images of the locations of injury using geotagged photographs children have taken themselves, complications and injury outcomes, and an assessment of overall risk-taking tendencies. Participants aged six-12, with the help of their photographs, were able to lay out the events leading up to, including, and following their injury. Much of this information was either not included in their medical charts or was markedly different. Themes included not being able to prevent the injury and being adventurous, as well as becoming more cautious afterwards. These can have applications to the necessity of exploration as well as possibilities to prevent injury or not. Thus, the in-depth, first-person retelling of injury mechanism illustrated the need for mechanistic data and statistics beyond injury location alone. Risk-taking behaviours, as scored by the Sensation Seeking Scale for Children, correlated to injury severity, which is known to be associated with poorer outcomes and long-lasting complications. PEI of children sustaining SCH fractures in Vancouver reveals mechanisms of injury beyond those previously reported in literature and suggest the feasibility of a large-scale study. PEI in this age group allows for clarifications and a clearer picture of injury mechanism as well as context of injury. These aspects significantly affect our ability to determine the relationship between injury mechanism and injury severity. Mixed-methods analysis of child-directed data as well as quantitative injury demographics reveals unique translational knowledge which can be shared with clinicians, patients/care-givers, community-based health teams, and local policy makers to make timely and impactful improvements in injury prevention, clinical practice, and play structure safety

Avascular necrosis (AVN) of the femoral head is a potentially devastating complication of treatment for developmental dysplasia of the hip (DDH). AVN most commonly occurs following operative management by closed (CR) or open reduction (OR). This occurrence has frequently been examined in single centre, retrospective studies, however, little high-level evidence exists to provide insight on potential risk factors. The purpose of this observational, prospective multi-centre study was to identify predictors of AVN following operatively-managed DDH. A multi-centre, prospective database of infants diagnosed with DDH from 0–18 months was analyzed for patients treated by CR and/or OR. At minimum one year follow-up, the incidence of AVN (Salter criteria) was determined from AP pelvis radiographs via blinded assessment and consensus discussion between three senior paediatric orthopaedic surgeons. Patient demographics, clinical exam findings and radiographic data were assessed for potential predictors of AVN. A total of 139 hips in 125 patients (102 female, 23 male) underwent CR/OR at a median age of 10.4 months (range 0.7–27.9). AVN was identified in 37 cases (26.6% incidence) at a median 23 months post-surgery. Univariate logistic regression analysis comparing AVN and no AVN groups identified sex, age at diagnosis, age at surgery, pre-surgery IHDI grade and time between diagnosis and surgery as potential predictive factors. Specifically, male sex (OR 2.21 [0.87,5.72]), IHDI grade IV, and older age at diagnosis (7.4 vs. 9.5 months) and surgery (10.2 vs. 13.6 months) were associated with development of AVN. Likewise, increased time between diagnosis and surgery (2.9 vs. 5.5 months) was also associated with a higher incidence. No association was found with surgery type (CR vs. OR), pre-surgery acetabular index or surgical hip. Development of AVN occurred in 26.6% of hips undergoing CR or OR at a median 23 months post-surgery. Male sex, older age at diagnosis and surgery, dislocation severity and increased time between diagnosis and surgery were associated with AVN. Longer-term follow-up and larger numbers will be required to confirm these findings. Early outcomes from this prospective patient cohort suggest that AVN is an important complication of operative management for DDH, and appears to occur at a comparable rate whether the reduction is performed open or closed. Male patients may be more susceptible to developing AVN and merits further exploration. Potential predictive factors of older age and length of time between diagnosis and surgery emphasize the importance of early detection and treatment to minimize complications and optimize outcomes

In the vast majority of patients, the anatomical and mechanical axes of the tibia in the coronal plane are widely accepted to be equivalent. This philosophy guides the design and placement of orthopaedic implants within the tibia and in both the knee and ankle joints. However, the presence of coronal tibial bowing may result in a difference between these two axes and hence cause suboptimal placement of implanted prostheses. Although the prevalence of tibial bowing in adults has been reported in Asian populations, to date no exploration of this phenomenon in a Western population has been conducted. The aim of this study was to quantify the prevalence of coronal tibial bowing in a Western population. This was an observational retrospective cohort study using anteroposterior long leg radiographs collected prior to total knee arthroplasty in our high volume arthroplasty unit. Radiographs were reviewed using a Picture Archiving and Communication System. Using a technique previously described in the literature for assessment of tibial bowing, two lines were drawn, each one third of the length of the tibia. The first line was drawn between the tibial spines and the centre of the proximal third of the tibial medullary canal. The second was drawn from the midpoint of the talar dome to the centre of the distal third of the tibial medullary canal. The angle subtended by these two lines was used to determine the presence of bowing. Bowing was deemed significant if more than two degrees. The position of the apex of the bow determined whether it was medial or lateral. Measurements were conducted by a single observer and 10% of measurements were repeated by the same observer and also by two separate observers to allow calculation of intraclass correlation coefficients (ICCs). A total of 975 radiographs consecutively performed in the calendar years 2015–16 were reviewed, 485 of the left leg and 490 of the right. In total 399 (40.9%) tibiae were deemed to have bowing more than two degrees. 232 (23.8%) tibiae were bowed medially and 167 (17.1%) were bowed laterally. The mean bowing angle was 3.51° (s.d. 1.24°) medially and 3.52° (s.d. 1.33°) laterally. Twenty-three patients in each group (9.9% medial/13.7% lateral) were bowed more than five degrees. The distribution of bowing angles followed a normal distribution, with the maximal angle observed 10.45° medially and 9.74° laterally. An intraobserver ICC of 0.97 and a mean interobserver ICC of 0.77 were calculated, indicating excellent reliability. This is the first study reporting the prevalence of tibial bowing in a Western population. In a significant proportion of our sample, there was divergence between the anatomical and mechanical axes of the tibia. This finding has implications for both the design and implantation of orthopaedic prostheses, particularly in total knee arthroplasty. Further research is necessary to investigate whether prosthetic implantation based on the mechanical axis in bowed tibias results in suboptimal implant placement and adverse clinical outcomes

We have looked at a single surgeons results for hip abductor repair in a population of patients and assessed them pre and post operatively. We collected data over a 2 year period and each patient underwent a telephone consultation and were scored both pre operatively and post operatively using the non-arthritic hip score (NAHS) and UCLA activity score (UCLA). A total of 15 patients were included in the study over a 2 year period. 93% underwent some form of investigation prior to surgery. Intra-operatively all patients were found to have pathological abductors. 9 patients were found to have partial avulsions of the abductors and the other 6 had under surface tears or detachments. The mean preoperative NAHS was 35.7/80 and >3/12 post operatively was 68.8/80 (p value <0.001). The mean preoperative UCLA score was 3.1/10 and >3/12 post operatively was 6.6/10 (p value <0.001). There is a statistically significant improvement in the NAHS of these patients as early as 3/12 and therefore early exploration is advised by the team. Surgical exploration is advised if the patient remains symptomatic despite having negative imaging results as this condition continues to go untreated despite the patients having a significant improvement post operatively

Spine surgery is common and costly. Researchers and policy makers believe that utilization of spine surgery in the US is significantly higher than in other industrialized countries. Although within-country variation in spine surgery utilization is well studied, there has been little exploration of variation in spine surgery between countries. We used population level administrative data from Ontario (years 2011–2015) and New York (2011–2014) to identify all adults who underwent inpatient spinal decompression or fusion surgery. We compared Ontario and New York with respect to patient demographics and the percentage of hospitals performing spine surgery. We compared rates of decompression and fusion surgery (procedures per-10,000 population per-year) in Ontario and New York for all procedures, emergent procedures alone, and elective procedures and after stratifying by patient age. Patients in Ontario were older than patients in New York for decompression (mean age 58.8 vs. 51.3 years, P<.001) and fusion (58.1 vs. 54.9, P<.001). A smaller percentage of hospitals in Ontario performed decompression or fusion compared to New York (decompression, 26.1% in Ontario vs 54.9% in New York: fusion 15.2% vs 56.7%, both P<.001). Overall, utilization of spine surgery in Ontario was 6.6 procedures per-10,000 population per-year and in New York was 18 per-10,000 per-year (P<.001). Ontario-New York differences in utilization were small for emergent cases (2 per-10,000 in Ontario vs. 2.8 in New York, P<.001), but large for elective cases (4.6 vs 15.2, P<.001). In analyses stratified by surgical subtype, differences in utilization of decompression in New York and Ontario were relatively modest (2.4 vs 3.1, P<.001), while utilization of fusion was approximately 400% higher in New York than Ontario (15.7 vs 3.5, P<.001). Further analysis demonstrated that the New York-Ontario difference in utilization was substantially larger among younger patients and smaller for older patients. For example, utilization of spine procedures in New York was 340% greater than Ontario for patients less-than 50 years of age (11.7 vs 3.4), but only 25% greater in patients age 80 and above (10 vs 12.6). After adjusting for patient demographics, hospital LOS and surgical urgency, differences in mortality in Ontario and New York were not significant for either decompression or fusion. In adjusted analyses differences in hospital LOS were slightly greater for decompression in Ontario, but similar for fusion and readmission rates in Ontario were significantly lower than in New York. In conclusion, we found significantly lower utilization of spine surgery in Ontario when compared to New York. The difference in utilization was attributable to less elective fusion surgery, primarily in younger (i.e. non-Medicare) patients. These findings can serve inform broader spine surgery policy reforms in both jurisdictions

Introduction. Initial stability of cementless total knee arthroplasty (TKA) tibial trays is necessary to facilitate biological fixation. Previous experimental and computational studies describe a dynamic loading micromotion test used to evaluate the initial stability of a design. Experimental tests were focused on cruciate retaining (CR) designs and walking gait loading. A FEA computational study of various constraints and activities found CR designs during walking gait experienced the greatest micromotion. This experimental study is a continuation of testing performed on CR and walking gait to include a PS design and stair descent activity. Methods. The previously described experimental method employed robotic loading informed by a custom computational model of the knee. Different TKA designs were virtually implanted into a specimen specific model of the knee. Activities were simulated using in-vivo loading profiles from instrumented tibia implants. The calculated loads on the tibia were applied in a robotic test. Anatomically designed cementless tibia components were implanted into a bone surrogate. Micromotion of the tray relative to the bone was measured using digital image correlation at 10 locations around the tray. Three PS and three CR samples were dynamically loaded with their respective femur components with force and moment profiles simulating walking gait and stair descent activities. Periods of walking and stair descent cycles were alternated for a total of 2500 walking cycles and 180 stair descent cycles. Micromotion data was collected intermittently throughout the test and the overall 3D motion during a particular cycle calculated. The data was normalized to the maximum micromotion value measured throughout the test. The experimental data was evaluated against previously reported computational finite element model of the micromotion test. Results. The maximum average micromotion was on the CR design during walking gait. The greatest CR micromotion during stair descent was 67% of the maximum. The maximum micromotion in the PS design was 55% of the CR walking maximum and occurred during stair descent. The next highest PS value was 52% during walking. The absolute difference in these values was under 3 µm. The majority of the PS micromotion values around the tray were less than 50% that of the maximum micromotion of the CR design. Discussion. The experimental continuation of this investigation into cementless tray stability aligned with computational results in this model. The computational model predicted the PS tray would have 50% of the micromotion of the CR design, which was close to the experimental test. For CR, the computational rank order for walking and stair descent was also the same in the experimental follow-up. Future work in this investigation will include continued validation of the computational and experimental models, including more designs. Further exploration into accounting for patient and surgical variability should be explored. For any figures or tables, please contact authors directly

Aims

Early large treatment effects can arise in small studies, which lessen as more data accumulate. This study aimed to retrospectively examine whether early treatment effects occurred for two multicentre orthopaedic randomized controlled trials (RCTs) and explore biases related to this.

Aims

The evidence base within trauma and orthopaedics has traditionally favoured quantitative research methodologies. Qualitative research can provide unique insights which illuminate patient experiences and perceptions of care. Qualitative methods reveal the subjective narratives of patients that are not captured by quantitative data, providing a more comprehensive understanding of patient-centred care. The aim of this study is to quantify the level of qualitative research within the orthopaedic literature.

Despite the vast quantities of published artificial intelligence (AI) algorithms that target trauma and orthopaedic applications, very few progress to inform clinical practice. One key reason for this is the lack of a clear pathway from development to deployment. In order to assist with this process, we have developed the Clinical Practice Integration of Artificial Intelligence (CPI-AI) framework – a five-stage approach to the clinical practice adoption of AI in the setting of trauma and orthopaedics, based on the IDEAL principles (https://www.ideal-collaboration.net/). Adherence to the framework would provide a robust evidence-based mechanism for developing trust in AI applications, where the underlying algorithms are unlikely to be fully understood by clinical teams.

Cite this article: Bone Joint Res 2024;13(9):507–512.

We present seven patients with recurrent haemarthroses after total knee arthroplasty, caused by an inherent platelet function defect. These patients developed painful knee swelling, persistent bleeding and/or wound breakdown, a platelet factor 3 availability defect being identified in all cases. Surgical exploration, with joint debridement, lavage and synovectomy, was performed in four patients who did not improve with conservative therapy. Histopathological examination of synovium revealed a focal synovial reaction with histiocytic infiltration, and occasional foreign-body giant cells. One patient required an early revision because of aseptic loosening of their tibial component. The condition was treated by single-donor platelet transfusions with good results. The diagnosis, management, and relevance of this disorder are discussed

Aims

The aim of this study was to develop and evaluate machine-learning-based computerized adaptive tests (CATs) for the Oxford Hip Score (OHS), Oxford Knee Score (OKS), Oxford Shoulder Score (OSS), and the Oxford Elbow Score (OES) and its subscales.

Significant advances in perioperative pain management, such as multimodal periarticular injection, and subtler advances in surgical technique have resulted in improved postoperative experiences for patients with less pain, earlier rehabilitation, and shorter stays in hospital. Concurrently, and by applying the learnings from above, significant advances have been made in unicompartmental knee arthroplasty care pathways leading to safe programs for outpatient surgery. A natural extension of this process has been the exploration of outpatient total joint arthroplasty (TJA). There are some papers written on the topic, but not many. The papers are generally report that outpatient TJA can be a safe and effective procedure, but the devil is in the detail. Firstly, most authors in this field carry a bias towards positive outcomes given they fact they are expert, academic, and innovative surgeons, often having controlling interest in the management of the complete perioperative pathway. Secondly, and largely as a result of the above, there is a major selection bias as to who receives outpatient TJA. In all cases, the patients are younger, fitter, and with less comorbidities. Patients reported in the published literature on outpatient TJA therefore do not represent the average patient that the average surgeon would operate on. Recall, TJA patients are becoming heavier and older patients (85+) are also receiving TJA at increasing rates. It is useful to remember that TJA is a stressful event from a physiological perspective for the patient. Serious complications, including death, can and do occur. Further, some significant events, like cardiac ischemia occur around the second to third day postoperatively. These patients often require medical intervention for stabilization and need readmission when sent home before these events occur. This obviously is not a trivial issue given the penalties applied to hospitals in the US for early readmissions after TJA. The fundamental questions at this early stage of outpatient TJA are 1) whether it is scalable to a larger audience, and 2) whether or not processes can be developed to make it a routine, standard of care. Given that the current literature is limited and written by expert surgeons on a highly select group of patients, and given that patients in general are getting older and less healthy, it is difficult to imagine a future of TJA as drive through surgery