The ability to drive represents autonomy and independence of individuals. For many patients not being able to drive severely restricts their social, personal and professional activities leading to adverse effects on their well being. This study assessed the current evidence on driving advice after total hip replacement (THR) and compared it with the real time ability of patients to drive their own cars after primary THR. We present a prospective review of car driving ability of 130 patients (80 males and 50 females) who were treated with THR. The results show that 105 patients (81%) were able to drive within 6–8 weeks after surgery. It took more than 12 weeks for 22 patients (17%) to start driving again. There was no reported deterioration in the driving ability after primary total hip replacement surgery. Conversely, 49 patients (38%) felt a subjective improvement in their driving capability after THR. Three patients (2%) were still not confident to drive even at 12 weeks post THR. In spite of the clear advice, only 69% practiced on a stationary car before driving on the road. In our study sample 67 patients (63.8%) had a right THR and 65 patients (61.9%) were manual car drivers and all were able to drive between 6–8 weeks. This study demonstrates that patients should not resume driving motor vehicles for a minimum period of six weeks following total hip replacement surgery. This is inclusive of automatic and manually operated automobiles, and irrespective of laterality of surgical interventions. Return to driving after a six week period should be based on the individual’s capability and confidence to control the vehicle safely. Patients should be given clear advice to practice on the stationary vehicles before starting to drive on the road

Distracted driving is now the number one cause of death among teenagers in the United States of America according to the National Highway Traffic Safety Administration. However, the risks and consequences of driving while distracted spans all ages, gender, and ethnicity. The Distractions on the Road: Injury eValuation in Surgery And FracturE Clinics (DRIVSAFE) Study aimed to examine the prevalence of distracted driving among patients attending hospital-based orthopaedic surgery fracture clinics. We further aimed to explore factors associated with distracted driving. In a large, multi-center prospective observational study, we recruited 1378 adult patients with injuries treated across four clinics (Hamilton, Ontario, Toronto, Ontario, Calgary, Alberta, Halifax, Nova Scotia) across Canada. Eligible patients included those who held a valid driver's license and were able to communicate and understand written english. Patients were administered questions about distracted driving. Data were analyzed with descriptive statistics. Patients average age was 45.8 years old (range 16 – 87), 54.3% male, and 44.6% female (1.1% not disclosed). Of 1361 patients, 1358 self-reported distracted driving (99.8%). Common sources of distractions included talking to passengers (98.7%), outer-vehicle distractions (95.5%), eating/drinking (90.4%), music listening/adjusting the radio (97.6%/93.8%), singing (83.2%), accepting phone calls (65.6%) and daydreaming (61.2%). Seventy-nine patients (6.3%), reported having been stopped by police for using a handheld device in the past. Among 113 drivers who disclosed the cause of their injury as a motor vehicle crash (MVC), 20 of them (17%) acknowledged being distracted at the time of the crash. Of the participants surveyed, 729 reported that during their lifetime they had been the driver in a MVC, with 226 (31.1%) acknowledging they were distracted at the time of the crash. Approximately, 1 in 6 participants in this study had a MVC where they reported to be distracted. Despite the overwhelming knowledge that distracted driving is dangerous and the recognition by participants that it can be dangerous, a staggering amount of drivers engage in distracted driving on a fairly routine basis. This study demonstrates an ongoing need for research and driver education to reduce distracted driving and its devastating consequences

INTRODUCTION. Hallux Valgus is a common foot condition, which may affect mobility and lifestyle. Corrective surgery is performed as a day case procedure, however, post-operatively; patients remain limited in their ability to drive for a variable period. In the laboratory settings, emergency brake response time after first metatarsal osteotomy has been studied but there is no published study of patients’ experience of driving after this surgery. This study was aimed at assessing patients’ driving ability and comfort after Hallux Valgus corrective surgery. METHODS. Fifty consecutive patients who underwent first metatarsal corrective osteotomy from January 2009 to July 2010 were reviewed. The operation type, foot side operated, postoperative complications and other conditions affecting driving were recorded from charts and operation notes. A telephonic survey was then conducted and information was recorded in a predesigned questionnaire. The questions included driving advice given by the medical staff, time interval to begin driving postoperatively, and how long the patient took to gain full confidence at driving. It was also noted whether patients required changing the type of car from manual to automatic. RESULTS. Of 50 patients, 10 never drove and were excluded. One patient had expired from unrelated health conditions. Two discontinued driving after surgery due to other (social) reasons, and one could not be contacted. The remaining thirty-six patients were analyzed. The mean age was 56.8+/-9.8 years with range of 36–74 years. Most were females (n=33, 91.7%), and the right side was operated upon in 17 (44.4%) patients. SCARF osteotomy was performed in 19 (52.8%) patients, basal osteotomy in 5 (13.9%), chevron osteotomy in 5 (13.9%) and other procedures (bunionectomy, Akin, soft tissue correction etc) were done in 7 (19.4%) patients. Out of the 28 patients driving manual cars, one required changing to automatic vehicle. The average post-operative period when patients resumed driving was 8.6 weeks with a range of 4 to 16 weeks. After SCARF, this average was 8.3 weeks (range 6–16), which was against 7.6(range 6–16) and 7.8 (range 4–12) weeks after basal and chevron procedures respectively (p=0.408). The mean period when patients reported comfortable foot control was 1.06 weeks after they had begun to drive for all groups. With SCARF this was 1.3 weeks, and 1.4 and 2.2 for basal and chevron groups respectively (p=0.162). Of the two patients that resumed driving after 16 weeks, one had infection and swelling of the foot postoperatively and the other had bilateral basal osteotomy performed simultaneously and was on crutches for 16 weeks. CONCLUSION. The mean time to resumption of automobile driving after corrective Hallux Valgus surgery is 8.6 weeks, and, on average patients takes another week to attain full confidence and comfort at driving postoperatively. There is no statistically significant difference between the types of surgery performed

INTRODUCTION. The primary goal of THA or TKA is to relieve pain and restore mobility. The success is determined by the longevity of prostheses and early return to routine activities, such as driving. With enhanced recovery regimens, patients are being discharged within 24–48hrs post-op.. The aim of this study was to determine when our patients returned to driving after anterior hip replacements and patient specific knee replacements. METHODOLOGY. This study included 207 soft tissue sparing anterior bikini THA and 146 patient specific instrumented (PSI) TKAs between Feb 2017 and March 2018. All patients included drove before surgery. Non-drivers were excluded. A detailed questionnaire was sent to all patients 3 to 6 weeks after surgery to record their driving status. 50 patients were randomly selected to assess flexion at the hip, knee, and ankle joints whilst seated in the driver's seat of their vehicle. RESULTS. There were 213 females and 124 males (mean age of 69 years) and average BMI of 18.24. There were 207 THAs (99 left, 106 right and 1 bilateral one stage) and 146 TKAs (L=70 & R=76). 76% of patients returned to driving within the first 3 weeks after surgery of which 32 patients (21 THAs (14%) and 11 TKAs (10%)) resumed driving within the first post-op week, 110 patients (69 THAs (39%)and 49 TKAs (35%)) drove in the second week and 73 (38 THAs (23%)and 38 TKAs(28%)) returned to driving in the third week. The rest of the 82 patients reports that they could have driven earlier but chose not to, since they had alternatives that they preferred. The earliest a patient resumed driving post-surgery was on the 2. nd. day(Post THA and TKA). 96.4% stated that they were confident when they first resumed driving. There were 40 patients out of the total 337 that did not return to driving post-surgery. 3 (2 hips and 1 knee) due to medical comorbidities and the rest 37 (14 THAs and 6TKAs) reported they had their children/spouses to drive them but were confident that they could have driven themselves if required. There was statistically no direct correlation between resumption of driving and the side of surgery. There were 282 patients driving automatic cars, 23 driving manual cars and the remaining did not comment. Out of the manual car drivers, 8 were operated on the left side (5 hips and 3 knees), but still all confidently returned to driving within 6 weeks earliest returning within the 1st week. Post measurement of angles of flexion at hip, knee and ankle while accelerating and braking among 50 patients we found that ankle movements significantly affect driving more so than hip and knee. CONCLUSION. We found that after soft tissue sparing anterior bikini THA and PSI TKA, patients were driving as early as within a week with the majority feeling confident and less apprehensive about recommencing driving, potentially due to enhanced recovery measures which were taken, including the minimally invasive surgical technique, local analgesia infiltration and early mobilization post procedure

Purpose: The objective of the study was to determine the changes in the driving pattern – especially the capacity to use the steering wheel after carpal tunnel surgery so that recommendation for suitability to return back to driving can be made. Methods Used: A computerised driving simulator normally used for driving assessment of drivers with disability at the regional mobility centre at the Wrightington Hospital was used to assess the patient’s driving. Static and dynamic steering torque was measured before and at 2 & 6 weeks after carpal tunnel release in 25 patients using the static assessment rig. Driving reaction time was also studied in these patients. Results: There was decrease from preoperative static steering torque to that at 2 weeks postoperatively but the dynamic steering torque did not differ in most cases. By 6 to 8 weeks postoperatively, the mean torque values for static and dynamic steering capacity had significantly improved. The driving reaction times at preoperative assessment did not differ significantly from the post operative ones at all times. Conclusion: Although at 2 weeks postoperatively the ability to use the operated hand for static steering had not returned in most patients, their overall steering capacity was not affected as suggested by their unaffected dynamic steering time and the reaction time

Introduction. Self tapping bone screw has been widely used in the fixation of Arthroplasty implants and bone graft. But the unwanted screw or driver breakage can be a direct result of excessive driving torque due to the thread cutting resistance. Previous studies showed that bone drill bit cutting rake angle was a critical factor and was inversely related to the bone cutting efficiency. 1, 2, 3, 4. (Figure 1) However to date there was no data for how the rake angle could influence the performance of self tapping bone screw. The purpose of this study was to investigate the torque generated by the self tapping cortical screw in simulated bone insertion as a function of the screw tip cutting flute rake angle. Methods. Two 5 mm thick BM5166 polyurethane block were stacked together and drilled through with 2.5mm diameter holes. Five 30mm long 3.5 mm diameter Ti6AL4V alloy self tapping cortical screws with 0°rake angle cutting flutes (Figure 2) were inserted in the holes and driven by the spanner attached to the test machine (Z5.0TN/TC-A-10) with a displacement control of 3 revolutions/min and 30N constant axial loading. The screws were driven into the stacked polyurethane block for 8mm depth. The maximum driving torque was recorded. Procedure was repeated for five same screws but with 7° rake angle cutting flutes. (Figure 2) The driving torqueses were compared. Student t test was performed with confidence level of 95% was assumed. Results. The average insertion driving torque for the screw with 7° rake angle was 30% less torque required than that of the screw with 0° rake angle. (P=5.3E–06<0.05) (Table 1). Conclusion and discussion. Screw failure during the insertion would be a nightmare. A slight positive rake angle significantly decreases the torque resistance. This design feature can significantly increase the safety margin of the self tapping screw implants and screw driving instruments. The likely mechanism would be the positive rake angle generated a more efficient bone cutting instead of pushing. More study on driving torque as a function of wider rake angle change is warranted. For figures and tables, please contact authors directly

Background: Recently, the effects of radiculopathy and nerve root blocks on driving reaction time (DRT) have been presented in the literature. To our knowledge, the relation between lumbar spinal fusion and DRT has not been studied before, although important for driving safety. So, we conducted the current study to test the hypotheses that DRT in the context of lumbar fusion is 1) altered in pre-postoperative comparison, 2) influenced by pain, 3) influenced by the patient’s driving skill and 4) different to the DRT of healthy controls. Methods: 21 consecutive patients (age 53.5 years, SD 10.8) receiving primary lumbar fusion were tested for their DRT 1 day preoperatively (pre-op), 1 week postoperatively at the day before discharge (post-op) and at 3 months (follow-up; FU). DRT was assessed with a custom made driving simulator. Additionally, also the level of back pain was determined by VAS for usual pain (VAS-U) and for pain during testing (VAS-T). We also collected the participants’ subjective driving frequency. We used normative DRT data from 31 healthy controls of similar age for comparison with the patients. Results: Pre-op DRT was 685 msec (Md; IQR 246), post-op DRT increased to 728 msec (Md; IQR 264) and decreased again to 671 msec (Md; IQR 202) at FU (p=0.007). Post-hoc analyses (alpha=0.017) found significant differences between post-op and FU DRT (p=0.007). Moderate to high correlations (between 0.537 and 0.680) were found between VAS of back pain and DRT (p between 0.001 and 0.012). No correlations were found between driving frequency and DRT. Controls showed a DRT of 487 msec (Md; IQR 116) which was significantly different from DRT of the patients at all three test occasions (p< 0.001). Conclusion: We found minor increase in DRT 1 week post-op followed by a definite and significant decrease at 3 months FU. We think it is safe – with respect to DRT - to resume driving 3 months after lumbar fusion. It is difficult to draw any conclusions about the period between discharge and 3 months. We also found moderate and high correlations between DRT and the level of back pain and assume that back pain is a relevant factor influencing DRT

In a society dependent upon the motor car, impaired driving ability is a significant disability which may affect patients with total knee replacement during the postoperative rehabilitation. Recently, there has been much interest in minimally invasive surgery for total knee arthroplasty (TKA). This study evaluated the hypothesis that a minimally invasive technique using a small incision (7 to 10 cm), and a minimal quadriceps muscle splitting without eversion of the patella (MIS approach) would have a beneficial effect on driving reaction time. 15 patients undergoing a primary TKA with the MIS approach were compared with 15 TKAs using a standard approach. An experimental car was used to measure the force and timing of pressure by the foot on accelerator and break pedals. The mean reaction time for normal adults was 0.442 s to go from the accelerator to the brake pedal. This time falls well within the code guideline of 0.7 s. The driving reaction times of the patients with knee arthroplasty were measured at one, two and three months after the operation. The ability to perform an emergency stop was assessed as the time taken to achieve a brake pressure of 100 N after a visual stimulus.The patients have an actual follow-up of 2 years. A clinical and radiological evaluation was performed. Radiographic analysis included evaluation of postoperative alignment variables and progressive radioluciencies. Over all 27 among the 30 knees have good and excellent objective knee Society Scores and patient satisfaction indices. The patients in the MIS group had a statistically shorter time until they could straight leg raise, used less epidural analgesia, used less overall analgesics and had a more rapid regaining of flexion. Patients with standard approach and technique for total knee replacement recovered sufficient knee function to return to driving at only three months after the operation according to the time and the force necessary to the brake pedal. Patients with mini invasive surgery approach have recovered sufficient knee function to return driving at one month after the operation. There was no significant difference in alignment of implants and in alignment of the knee between the two groups. Three knees had radioluciencies (two with a standard incision and one with a MIS approach). Using a small incision without patellar eversion does not jeopardize the alignment of the implants and improves postoperative rehabilitation

The time at which patients should drive following total hip replacement (THR) is dependant upon recovery and the advice they are given. The Driver Vehicle and Licensing Agency (DVLA) in the United Kingdom does not publish recommendations following THR and insurance companies usually rely on medical instruction. Few studies have been performed previously and have reached different conclusions. Brake reaction times for patients undergoing primary THR were measured pre-operatively and at four, six and eight weeks after surgery using a vehicle driving simulator at a dedicated testing centre. Patients were prospectively recruited. Ethical approval was granted. Participants included eleven males and nine females, mean age 69 years. Side of surgery, frequency of driving and type of car (automatic or manual) were documented. Patients with postoperative complications were excluded. No adverse events occurred during the study. Statistical analysis using Friedman's test demonstrated a statistically significant difference (P=0.015) in reaction times across the four time periods. Wilcoxon test demonstrated a highly significant difference between initial and six week mean results (P=0.003), and between four and six week results (P=0.001). No significant difference was found between six and eight weeks. Our data suggests reaction times improve until week six and significantly between week four to six. Patients making an uncomplicated recovery following primary THR may be considered safe to return to driving from week six onwards. We recommend this is clearly documented in the medical notes, and patients should check with their insurance company prior to recommencement

Purpose: Until now no experimental study has evaluated the effect of orthopedic immobilizations of the lower right limb on driving performances. Clinicians and legislators therefore cannot appropriately advise patients with this type of treatment on their driving capabilities and put forth recommendations for road safety. Method: An experimental study of the effect of orthopedic immobilizations of the lower right limb on driving performances has been conducted at the Research Center on Aging of the Sherbrooke Geriatric University Institute. The breaking capabilities of forty-eight healthy volunteers were tested in three conditions: wearing their usual running shoes and two types of immobilization, namely the walking cast (Delta-Cast Conformable, BSN Medical, Leuven, Belgium) and the foam pneumatic walker (Aircast, Vista, CA). The order in which each condition was tested was randomly determined for each volunteer. A custom driving simulator was used to measure the force applied on the break pedal and the breaking time using the software LabVIEW (National Instruments, Austin, TX). In addition, each volunteer completed a socio-demographic survey, a brief physical exam and two clinical tests (stepping and standing). Results: The average maximum breaking forces exerted by the volunteers with the walking cast, the foam walker and the shoes are 275,4 lb, 287,2 lb and 293,8 lb respectively. The two significant differences are between the walking cast and the shoes (18,4 lb, p< 0,001) and between the walking cast and the foam walker (11,8 lb, p< 0,001). The measured average breaking reaction times are (from the slowest to the fastest) 619 ms, 609 ms, and 580 ms with the foam walker, the walking cast and the shoes respectively. The two significant differences are between the shoes and the foam walker (39 ms, p< 0,001) and between the shoes and the walking cast (29 ms, p< 0,001). The results of this study also confirm the correlation between the measured breaking reaction times and the stepping and standing clinical test (p< 0,05). Conclusion: Although this study observed statistically significant changes in breaking force and reaction time in volunteers wearing two common

The time at which patients should drive following total hip replacement (THR) is dependant upon recovery and the advice they are given. The Driver Vehicle and Licensing Agency (DVLA) do not publish recommendations following THR and insurance companies usually rely on medical instruction. Brake reaction times for patients undergoing THR were measured before and four, six and eight weeks after surgery using a vehicle-driving simulator. Patients were prospectively recruited. Ethical approval was granted. Participants included eleven males and nine females, mean age 69 years. Side of surgery, frequency of driving and type of car (automatic or manual) were documented. Patients with postoperative complications were excluded. No adverse events occurred during the study. Statistical analysis using Friedman’s test demonstrated a statistically significant difference (P=0.015) in reaction times across the four time periods. Wilcoxon test demonstrated a highly significant difference between initial and six week mean results (P=0.003), and between four and six week results (P=0.001). No significant difference was found between six and eight weeks. Our data suggests reaction times improve until week six and significantly between week four to six. Patients making an uncomplicated recovery should be considered safe to drive by week six

Introduction: Insufficiency of poroelastic bone bending as the sole mechanism driving bone interstitial fluid flow (BIFF) to account for the shear stress required to activate mechanoreceptors on osteocytes and osteoblasts, has stimulated a search for alternative or complementary mechanisms in the quest for a comprehensive bone remodeling model. Some investigators, noting that a substantial amount of interstitial fluid is exchanged with blood and lymphatic capillaries, have suggested that this exchange may play a substantial role in both microtransport through the collagen matrix and lacunar-canalicular transport. In order to accept the vascular system as a significant source of transport driving BIFF, it must first be demonstrated that capillary filtration, the proc ess by which fluid is transported from blood vasculature, is sufficiently convective to drive interstitial percolation. We have proposed that while, as shown by Otter et al., resting transmural vascular pressures are sufficient to generate streaming potentials across cortical bone, it is likely that these forces must be complemented by muscle pump contractions during exercise to generate convective percolation flows which will develop the required mechanotransducer shear stress activation threshold. To determine a minimal baseline for a muscle pump driven BIFF (MPD-BIFF) model, we have investigated the role of repetitive skeletal muscle contractions, uncoupled from gravitational loading, on blood flow and capillary filtration in cortical bone of the rabbit tibia. We tested the hypothesis that these effects increased when the muscle pump was activated. Materials & Methods: The experimental model combined non-invasive, low magnitude transcutaneous neuromuscular stimulation (TENS), with real-time measurements from intravital microscopy (IVM) of optical bone chamber implants. Sling suspension of rabbits was utilized to eliminate gravitational reaction forces throughout TENS and data collection. TENS-induced muscle contraction forces were measured in situ, resultant bone strains were calculated, and systemic circulatory parameters were monitored, in order to eliminate these factors as contributors to blood flow changes. Blood flow rates and capillary filtration were measured by video-image analysis of 1 μm fluorescent microspheres and dextran-conjugated fluorescein isothiocyanate (FITC) and rhodamine (ITC) injected intravascularly during IVM. Bone formation, angiogenesis, and mineral apposition rates (tetracycline labelling) were analyzed from weekly microscopy pictures. Changes in bone mineral content and density were determined with CT scans obtained at implantation and termination. Results: Mechanical loading and baseline systemic circulation did not significantly contribute to the findings. Rhythmic muscle contractions were shown to increase cortical blood flow, rate of capillary filtration, rate of bone apposition, and angiogenesis. Discussion: The hypothesis was supported by the data. However, since no measurements were made on single capillaries, we could not confirm previous reports by this laboratory of convective extravasation

Introduction

Wear of polyethylene tibial inserts has been cited as being responsible for up to 25% of revision surgeries, imposing a very significant cost burden on the health care system and increasing patient risk. Accurate measurement of material loss from retrieved knee bearings presents difficult challenges because gravimetric methods are not useful with retrievals and unworn reference dimensions are often unavailable. Geometry and the local anatomy restrict in vivo radiographic wear analysis, and no large-scale analyses have illuminated long-term comparative wear rates and their dependence on design and patient factors. Our study of a large retrieval archive of knee inserts indicates that abrasive/adhesive wear of polyethylene inserts, both on the articular surface and on the backside of modular knees is an important contributor to wear, generation of debris and integrity of locking geometry.

The objective of the current study is to quantify wear performance of tibial inserts in a large archive of retrieved knees of different designs. By assessing wear in a large and diverse series, the goal is to discern the effect on wear performance of a number of different factors: patient factors that might help guide treatment, knee design factors and bearing material factors that may inform a surgeon's choice from among the array of arthroplasty device options.

The ankle joint offers adverse conditions to any prosthetic replacement: high loads on small surfaces, only vague landmarks for the insertion, complex and individually very different functional anatomy.

Despite these obstacles many excellent short- and some long-term results have been published, giving little way to a learning curve. This contrasts with our own experiences over at all 29 years now: 24 % failures of cemented two-component EP’s after 14,6 (6,1–21,2) years (n=67) and 8,7 % failures of uncemented tri-component EP’s after 3,7 (0,6–7,6) years (n=92).

We analyze and explain special problems and typical failures by a brief historical review of ankle joint replacement: as a logical sequence of various concepts, each of them basing on the knowledge of preceding insufficiencies. The general concern of the functionally useful, but limited mobility after the implantation will be discussed, also on the basis of own early and medium-term results: ROM ranging on average from 26° for TPR-(n=35) and 29° for New Jersey LCS-(n=30) up to 35° for S. T. A. R.-prostheses (n=12). Possible solutions of problems will be considered, respecting assumed causalities.

Basing on the literature and own earlier investigations, especially the long-term results will be compared critically.

The incertitude of an exact implantation has been partly compensated by the actual „meniscal“ concept of tricomponent prostheses. It should be favourable for their fixation to the bone and moreover reduce polyethylene-wear. But – as before – the discrepancy of high loads on a small area threatens the durability of ankle joint prostheses.

Prosthetic replacement has become indispensable in the treatment of painfully destructed ankle joints, but it demands a careful and critical indication.

Tendon injury is debilitating and recalcitrant. With limited knowledge of disease aitiology we have are lacking in effective treatments for this prevalent musculoskeletal complaint. This presentation will outline our findings over the past few years in which we have demonstrated the importance of the interfascicular matrix (IFM) niche in maintaining healthy tendon function and driving disease progression. 1,2. It will also continue to describe our progress in developing both in vivo and in vitro models to interrogate disease progression. We have developed and validated a rat Achilles tendon overload model, in order to explore the impact of loading on IFM and fascicle structure, and the resulting cell response. Data highlights that structural disruption and inflammatory response both initiate in the IFM region, and can be seen in the absence of demonstrable changes to animal gait, indicating a sub-injury response in the tendon which we hypothesis may drive increased matrix turnover and repair. 3. . We are now looking to interrogate the pathways driving this inflammatory behaviour in an organ-chip model, exploring the interplay between IFM cells and cells within fascicles. We have demonstrated phenotypic distinction of cells from the two niche environments, localized the progenitor phenotype to the IFM region and demonstrated significant mechanosensitivity in the IFM cell population. 4. We are currently building appropriate niche environments to maintain cell phenotype in our in vitro models, to explore the metabolic changes associated with disease progression. Acknowledgements: This body of work has received funding from: BBSRC (BB/K008412 /1); Versus Arthritis (project grant 20262); Horserace Betting Levy Board (T5); Dunhill Medical Charity (project grant RPGF1802\23); MRC (MR/T015462/1)

There is controversy regarding the effect of different approaches on recovery after THR. Collecting detailed relevant data with satisfactory compliance is difficult. Our retrospective observational multi-center study aimed to find out if the data collected via a remote coaching app can be used to monitor the speed of recovery after THR using the anterolateral (ALA), posterior (PA) and the direct anterior approach (DAA). 771 patients undergoing THR from 13 centers using the moveUP platform were identified. 239 had ALA, 345 DAA and 42 PA. There was no significant difference between the groups in the sex of patients or in preoperative HOOS Scores. There was however a significantly lower age in the DAA (64,1y) compared to ALA (66,9y), and a significantly lower Oxford Hip Score in the DAA (23,9) compared to PA(27,7). Step count measured by an activity tracker, pain killer and NSAID use was monitored via the app. We recorded when patients started driving following surgery, stopped using crutches, and their HOOS and Oxford hip scores at 6 weeks. Overall compliance with data request was 80%. Patients achieved their preoperative activity level after 25.8, 17,7 and 23.3 days, started driving a car after 33.6, 30.3 and 31.7 days, stopped painkillers after 27.5, 20.2 and 22.5 days, NSAID after 30.3, 25.7, and 24.7 days for ALA, DAA and PA respectively. Painkillers were stopped and preoperative activity levels were achieved significantly earlier favoring DAA over ALA. Similarly, crutches were abandoned significantly earlier (39.9, 29.7 and 24.4 days for ALA, DAA and PA respectively) favoring DAA and PA over ALA. HOOS scores and Oxford Hip scores improved significantly in all 3 groups at 6 weeks, without any statistically significant difference between groups in either Oxford Hip or HOOS subscores. No final conclusion can be drawn as to the superiority of either approach in this study but the remote coaching platform allowed the collection of detailed data which can be used to advise patients individually, manage expectations, improve outcomes and identify areas for further research

Escalating health care expenditure worldwide is driving the need for effective resource decision-making, with medical practitioners increasingly making complex resource decisions within the context of patient care. Despite raising serious legal and ethical issues in practice, this has attracted little attention in Australia, or internationally. In particular, it is unknown how orthopaedic surgeons perceive their obligations to the individual patient, and the wider community, when rationing care, and how they reconcile competing obligations. This research explores legal and ethical considerations, and resource allocation by Australian orthopaedic surgeons, as a means of achieving public health cost containment driven by macro-level policy and funding decisions. This research found that Australian orthopaedic surgeon's perceptions, and resource allocation decision making, can be explained by understanding how principles of distributive justice challenge, and shift, the traditional medical paradigm. It found that distributive justice, and challenges of macro level health policy and funding decisions, have given rise to two new medical paradigms. Each which try to balance the best interests of individual patients with demands in respect of the sustainability of the health system, in a situation where resources may be constrained. This research shows that while bedside rationing has positioned the medical profession as the gate keepers of resources, it may have left them straddling an increasingly irreconcilable void between the interests of the individual patient and the wider community, with the sustainability of the health system hanging in the balance

Aims. This study examined the relationship between obesity (OB) and osteoporosis (OP), aiming to identify shared genetic markers and molecular mechanisms to facilitate the development of therapies that target both conditions simultaneously. Methods. Using weighted gene co-expression network analysis (WGCNA), we analyzed datasets from the Gene Expression Omnibus (GEO) database to identify co-expressed gene modules in OB and OP. These modules underwent Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and protein-protein interaction analysis to discover Hub genes. Machine learning refined the gene selection, with further validation using additional datasets. Single-cell analysis emphasized specific cell subpopulations, and enzyme-linked immunosorbent assay (ELISA), protein blotting, and cellular staining were used to investigate key genes. Results. WGCNA revealed critical gene modules for OB and OP, identifying the Toll-like receptor (TLR) signalling pathway as a common factor. TLR2 was the most significant gene, with a pronounced expression in macrophages. Elevated TLR2 expression correlated with increased adipose accumulation, inflammation, and osteoclast differentiation, linking it to OP development. Conclusion. Our study underscores the pivotal role of TLR2 in connecting OP and OB. It highlights the influence of TLR2 in macrophages, driving both diseases through a pro-inflammatory mechanism. These insights propose TLR2 as a potential dual therapeutic target for treating OP and OB. Cite this article: Bone Joint Res 2024;13(10):573–587

Despite osteoarthritis (OA) representing a large burden for healthcare systems, there remains no effective intervention capable of regenerating the damaged cartilage in OA. Mesenchymal stromal cells (MSCs) are adult-derived, multipotent cells which are a candidate for musculoskeletal cell therapy. However, their precise mechanism of action remains poorly understood. The effects of an intra-articular injection of human bone-marrow derived MSCs into a knee osteochondral injury model were investigated in C57Bl/6 mice. The cell therapy was retrieved at different time points and single cell RNA sequencing was performed to elucidate the transcriptomic changes relevant to driving tissue repair. Mass cytometry was also used to study changes in the mouse immune cell populations during repair. Histological assessment reveals that MSC treatment is associated with improved tissue repair in C57Bl/6 mice. Single cell analysis of retrieved human MSCs showed spatial and temporal transcriptional heterogeneity between the repair tissue (in the epiphysis) and synovial tissue. A transcriptomic map has emerged of some of the distinct genes and pathways enriched in human MSCs isolated from different tissues following osteochondral injury. Several MSC subpopulations have been identified, including proliferative and reparative subpopulations at both 7 days and 28 days after injury. Supported by the mass cytometry results, the immunomodulatory role of MSCs was further emphasised, as MSC therapy was associated with the induction of increased numbers of regulatory T cells correlating with enhanced repair in the mouse knee. The transcriptomes of a retrieved MSC therapy were studied for the first time. An important barrier to the translation of MSC therapies is a lack of understanding of their heterogeneity, and the consequent lack of precision in its use. MSC subpopulations with different functional roles may be implicated in the different phases of tissue repair and this work offers further insights into repair process

Occlusal loading and muscle forces during mastication aids in assessment of dental restorations and implants and jaw implant design; however, three-dimensional bite forces cannot be measured with conventional transducers, which obstruct the native occlusion. The aim of this study was to combine accurate jaw kinematics measurements, together with subject-specific computational modelling, to estimate subject-specific occlusal loading and muscle forces during mastication. Motion experiments were performed on one male participant (age: 39yrs, weight: 82kg) with healthy dentition. Two low-profile magnetic sensors were fixed to the participant's teeth and the two dental arches digitised using an intra-oral scanner. The participant performed ten continuous of chewing on a polyurethane rubber sample of known material properties, followed by maximal compression (clenching). This was repeated at the molars, premolars of both the left and right sides, and central incisors. Jaw motion was simultaneously recorded from the sensors, and finite element modelling used to estimate bite force. Specifically, simulations of chewing and biting were performed by driving the model using the measured kinematics, and bite force magnitude and direction quantified. Muscle forces were then evaluated using a rigid-body musculoskeletal model of the patient's jaw. The first molars generated the largest bite forces during chewing (left: 309 N, right: 311 N) and maximum-force biting (left: 496 N, right: 495 N). The incisors generated the smallest bite forces during chewing (75 N) and maximum-force biting (114 N). The anterior temporalis and superficial masseter muscles had the largest contribution to maximum bite force, followed by the posterior temporalis and medial pterygoid muscles. This study presents a new method for estimating dynamic occlusal loading and muscle forces during mastication. These techniques provide new knowledge of jaw biomechanics, including muscle and occlusal loading, which will be useful in surgical planning and jaw implant design