We present a review of 97 consecutive BioPro. ®. metallic hemiarthroplasties performed in 80 patients for end-stage hallux rigidus, with a minimum of five years follow-up. The mean age of the cohort was 55 (22 to 74) years. No patient was lost to follow-up. There were 15 revisions performed, one for infection, two for osteolysis, and 12 for pain. The all cause survival rate at five years was 85.6% (95% confidence interval (CI) 83.5 to 87.9). Younger age was a significant predictor of revision (odds ratio 1.09, 95% CI 1.02 to 1.17, p=0.014) on excluding infection and adjusting for confounding variables (Cox regression). Significant improvements were demonstrated at 5 years in the Manchester Oxford foot questionnaire (13.9, 95% CI 10.5 to 17.2) and in the physical component of the short form 12 score (6.5, 95% CI 4.1 to 8.9). The overall satisfaction rate was 72%. The cost per quality-adjusted-life-year at 5 years, accounting for a 3% per year revision rate, was £3,714. The BioPro offers good short to mid-term functional outcome and is a cost effective intervention. The relative high revision rate is associated with younger age and the use of this implant may be limited to older patients

Introduction:. The treatment of 3- or 4-part proximal humeral fractures in elderly can be carried out with hemiarthroplasty. Also hemiarthroplasty has performed for failed osteosynthesis or conservative treatment in Japan. However the secondary hemiarthroplasty has poor clinical outcome. The aim of this study was to compare the clinical outcomes of primary and secondary hemiarthroplasty for proximal humeral fractures. Materials and Methods:. Between March 2004 and January 2013, twenty-four shoulders in 23 patients (22 females, 1 male) with proximal humeral fractures and fracture dislocations underwent hemiarthroplasty. The mean age was 75.6 years and the average follow-up period was 25.6 months (range 3 to 108 months). Eighteen shoulders in 17 patients were treated primary with hemiarthroplasty (primary group). Six shoulders in 6 patients were treated with hemiarthroplasty after other treatments had failed (secondary group). All patients were evaluated with the Japan Orthopaedic Association shoulder scoring system (JOA score) and range of motion. Results:. The mean JOA score was 66.7 points in primary group and 50.6 points in secondary group. Patients in primary group had significantly better score than secondary group (p < 0.05). At the final follow-up, the mean flexion angle was 81.4 degrees in primary group and 55.0 degrees in secondary group. The mean abduction angle was 79.7 degrees in primary group and 46.7 degrees in secondary group. The mean external rotation angle was 16.1 degrees in primary group and 5.0 degrees in secondary group. There was a significant difference in abduction angle between primary and secondary group (p < 0.05). On the other hand there was no significant difference in flexion and external rotation angle between primary and secondary group (p = 0.10, 0.03). Conclusions:. In this study primary group demonstrated good clinical results rather than in secondary group. Secondary hemiarthroplasty for failed early treatment is technically difficult. Important factors for secondary hemiarthroplasty include the reconstruction of tuberosities and technique to treat soft tissues such as deltoid gently

Abstract. Background. 1. 63,284 patients presented with neck of femur fractures in England in 2020 (NHFD report 2021)2. To maximise theatre efficiency during the first wave of COVID-19, NHSE guidance recommended the use of HA for most patients requiring arthroplasty.3. The literature reports an incidence of Hemiarthroplasty dislocations of 1–15%. Aims. 1. To study the number and possible causes of dislocations in patients with Primary hemiarthroplasty for fracture neck of femur2. To compare our data with national and international data in terms of dislocation and revision rates for Hemiarthroplasty. Methods. Retrospective study Duration- 1st April 2021–31st March 20223. Inclusion criteria- Patients with neck of femur fracture treated with Hemiarthroplasty. Exclusion criteria- Patients treated with other surgical options for neck of femur fractures. Results. 1. No. of neck of femur patients- 4442. No. of patients treated with Hemiarthroplasty- 2143. No. of dislocations- 44. 75% were female, 75% had AMTS>7, 50% were operated within 36 hours of trauma, 75% dislocated within a month of surgery, 75% of the dislocations were revised. 5. One dislocation was due to >72 hour delay to surgery, second dislocation was due to smaller offset and shortening, third was due to acetabular dysplasia, fourth was due to larger head used. Discussion-1. Our 1.86% dislocation rate matches that in the literature of 1–6%2. 75% dislocated within a month of surgery matches that in the literature that maximum dislocations occur within one month. 3. Closed reduction as definitive method of management of dislocation 25% matches that in the literature of 22–25%4. 75% dislocations revised similar to literature of 75–80% revision rate. Conclusion. Pre-operative templating can reduce surgical error involving limb length discrepancy and shortening to prevent dislocations. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

NICE Guidelines suggest patients should be offered a Total Hip Replacement (THR) rather than Hemiarthroplasty for a displaced intracapsular hip fracture. We investigated outcomes of patients aged 40–65 who received a THR or Hemiarthroplasty following a traumatic intracapsular hip fracture and had either high-risk (Group 1) or low-risk (Group 2) alcohol consumption (>14 or <14 units/week respectively). This was a retrospective study (April 2008 – December 2018) evaluating patients who underwent THR or Hemiarthroplasty in Greater Glasgow and Clyde. Atraumatic injuries, acetabular fractures, patients with previous procedures on the affected side and those lost to follow up were excluded. Analysis of length of admission, dislocation risk, periprosthetic fractures, infection risk, and mortality was conducted between both cohorts. Survival time post-operatively of Group 1 patients with a THR (61.9 months) and Hemiarthroplasty (42.3 months) were comparable to Group 2 patients with a THR (59 months) and Hemiarthroplasty(42.4 months). Group 1 patients with THR had increased risk of dislocation (12.9%; p=0.04) compared to those that received Hemiarthroplasty (2.5%). Group 1 Hemiarthroplasty patients had increased wound infection risk (11.6%) compared to Group 2 (3.7%). In conclusion, we found that amongst our population the life expectancy of a post-operative patient was short irrespective of whether they had high or low-risk alcohol consumption. A hip fracture may represent increased frailty in our study population. The Group 1 THR cohort presented a higher risk of hip dislocation and periprosthetic fracture. With this in mind, Hemiarthroplasty is a more cost-effective and shorter operation which produces similar results

Hip precautions are currently practiced in three-quarters of trauma hospitals in the UK, despite national recommendations from the ‘Blue Book’ not stating it as a requirement. Valuable therapist time is utilised alongside the need for specialised equipment, which can potentially delay discharge whilst it is being arranged. Objective of this study was to explore the current practice of the use of hip precautions on discharge following hemiarthroplasty for hip fractures. To also explore whether they are necessary and to identify areas for improvement to benefit patient care overall. Online survey distributed to various Trauma and Orthopaedic Departments across the UK. Survey was available over a 4-month period, collecting 55 responses overall. Majority of responses were from trauma and orthopaedic consultants who were aware of the ‘Blue Book’ recommendations. The majority of trusts who responded did not practice hip precautions and did not feel this increased the risk of dislocations on discharge. Recommendations included integration of hip precautions in the post-op advice in coordination with the physiotherapist and information leaflets on discharge regarding hip precautions. Hip precautions were not commonly practiced, for reasons including patient compliance and the inherently stable procedure of a hemiarthroplasty compared to a THR, reducing the need for hip precautions. Hip precautions are not widely regarded as a useful practice for post-hip hemiarthroplasty, viewed as utilising more resources and increasing costs and risk due to increased hospital stay. Thus, this potentially delays discharge overall. A consistent approach should be implemented in treating patients post-hip hemiarthroplasty

The incidence of hip fractures in the elderly is increasing. Minimally displaced and un-displaced hip fractures can be treated with either internal fixation or hemiarthroplasty. The aim was identifying the revision rate of internal fixation and hemiarthroplasty in patients 60 years or older with Garden I or II hip fractures and to identify risk factors associated with each method. A retrospective analysis was conducted from 2 Major Trauma Centres and 9 Trauma Units between 01/01/2015 and 31/12/2020. Patients managed conservatively, treated with a total hip replacement and missing data were excluded from the study. 1273 patients were included of which 26.2% (n=334) had cannulated hip fixation (CHF), 19.4% (n=247) had a dynamic hip screw (DHS) and 54.7% (n=692) had a hemiarthroplasty. 66 patients in total (5.2%) required revision surgery. The revision rates for CHF, DHS and hemiarthroplasty were 14.4%, 4%, 1.2% (p<0.001) respectively. Failed fixation was the most common reason for revision with the incidence increasing by 7-fold in the CHF group [45.8% (n=23) vs. 33.3% (n=3) in DHS; p<0.01]. The risk factors identified for CHF revision were age >80 (p<0.05), female gender (p<0.05) and smoking (p<0.05). The average length of hospital stay was decreased when using CHF compared to DHS and hemiarthroplasty (12.6 days vs 14.9 days vs 18.1 days respectively, p<0.001) and the 1 year mortality rate for CHF, DHS and hemiarthroplasty was 2.5%, 2% and 9% respectively. Fixation methods for Garden I and II hip fractures in elderly patients are associated with a higher revision rate than hemiarthroplasty. CHF has the highest revision rate at 14.4% followed by DHS and hemiarthroplasty. Female patients, patients over the age of 80 and patients with poor bone quality are considered high risk for fixation failure with CHF. When considering a fixation method in such patients, DHS is more robust than a screw construct, followed by hemiarthroplasty

Debate continues about the best treatment for patients over 65 years with non-displaced subcapital hip fractures: internal fixation (IF) or hemiarthroplasty (HA). Surgical aggression, mortality, complications and recovery of walking ability after 1year have been compared between both treatments. Match-paired comparison of 2 retrospective cohorts. 220 patients with IF vs 220 receiving a cemented bipolar HA. Matching by age (82.6±7.16 years (65–99)), sex (74.5% women), year of intervention (2013–2021) and ASA scale (24.2% ASA II, 55.8% III, 20.0% IV). Age (p=0.172), sex (p=0.912), year of intervention (p=0.638) and ASA scale (p=0.726) showed no differences. Surgical aggression smaller in IF: Surgical time (p< 0,00001), haemoglobin/haematocrit loss (p <0,00001), need for transfusion (p<0,00008), in-hospital stay (p<0,00001). Mortality: higher in-hospital for hemiarthroplasties (12 deaths (5.5%) vs 1 (0.5%) (p=0.004) (RR=12, 1.5–91.5)). But no significant differences in 1-month (13 hemiarthroplasties, 6%, vs 9 osteosynthesis, 4.1%) and 1-year mortality (33 hemiarthroplasties, 15%, vs 35, 16%). Medical complications: no differences in urinary/respiratory infections, heart failure, ictus, myocardial infarction, digestive bleeding, pressure sores or pulmonary embolus (p=0.055). Surgical complications: no significant differences. HA: 6 intraoperative (2,7%) and 5 postoperative periprosthetic fractures (2,3%), 5 infections (2,3%), 10 dislocations (4,5%), 3 neurovascular injuries. IF: 10 acute fixation failures (4,5%), 2 infections (0,9%), 9 non-unions (4,1%), 16 ischemic necrosis (7,3%). Functional results: no significant differences; 12 patients in each group (5,5%) never walked again (p=1), 110 HA (50%) and 100 IF (45.5%) suffered worsening of previous walking ability (p=0.575), 98 HA (44%) and 108 IF patients (49%) returned to pre-fracture walking ability (p=0.339). Fixation with cannulated screws may be a better option for non-displaced femoral neck fractures because recovery of walking ability and complications are similar, while surgical aggression and in-hospital mortality are lower

Background: Alternative treatments in displaced fractures of the femoral neck include reduction and internal fixation, and arthroplasty. A variety of treatments are continuously introduced to the health care market and that makes prioritising, based on the severity of the disease, the effectiveness, and the cost effectiveness of the treatment, necessary. The aim of this study was to compare the estimated effect and costs of internal fixation and hemiarthroplasty after a displaced femoral neck fracture. Methods: 222 patients, 165 (74%) women, mean age 83 years, were randomized to internal fixation (n = 112) and hemiarthroplasty (n = 110). Mainly due to cognitive failure or death, 56 patients failed to complete the EQ-5D questionnaire at any follow up; hence, 166 patients were included in the analysis. There were no differences in the demographic variables at inclusion. Patients underwent either a Charnley-Hastings bipolar cemented hemiarthroplasty or closed reduction and internal fixation with two parallel cannulated screws (Olmed). The health effect was estimated by the generic measure quality adjusted life-years (QALYs). The QALYs were estimated based on the patients’ perception of quality of life (QoL) assessed by Eq-5d, which was measured after 4, 12 and 24 months. Results: Over the two year period the expected QALYs for patient with hemiarthroplasty and internal fixation were estimated to be 1.31 and 1.11, respectively. Thus, the incremental health effect, the difference in QALYs for hemiarthroplasty versus internal fixation, was 0.20 QALYs gained. Hospital costs over two years were € 30 726 in the internal fixation group and € 27 618 in the hemiarthroplasty group, an incremental cost of – € 3 108 in favor of hemiarthroplasty. Total costs, including societal costs, were € 62 815 in the internal fixation group, compared to € 48 227 in the hemiarthroplasty group, an incremental cost of – € 14 588 in favor of hemiarthroplasty. By dividing the incremental cost by the incremental effect, we found the incremental cost effectiveness ratio (ICER) to be – € 15 540 for all hospital costs and – € 72 940 for total costs. Sensitivity analysis based on the bootstrap method, indicate that the ICER is significantly negative, indicating both a significantly lower incremental costs and significantly higher QALYs for hemiarthroplasty versus internal fixation. Conclusion: Primary treatment with hemiarthroplasty generates more QALYs and is less costly compared to internal fixation. Hemiarthroplasty was thus the cost effective treatment alternative

Abstract. Background. Dislocation of a hip hemiarthroplasty is a devastating complication with a high mortality rate in elderly patients. Previous studies have suggested a higher dislocation rate in patients with neuromuscular conditions. In this study, we have reviewed our larger cohort of patients to identify whether there is any association between neuromuscular disorders and prosthetic dislocation in patients treated with hip hemiarthroplasty for femoral neck fractures. Patients and Methods. Our study is a retrospective analysis of data collected over 34 years for patients with intracapsular neck of femur fracture who underwent hip hemiarthroplasty. The study population is composed of four groups: patients with no neuromuscular disorders, patients with Parkinson's disease, patients with previous stroke, and patients with dementia. Results. A total of 3827 patients were treated with hip hemiarthroplasty. For the 3371 patients with no neuromuscular condition (Group I) the dislocation rate was 1.1%. 219 patients had Parkinsonism (Group II) with a dislocation rate of 3.2%, 104 patients had a previous stroke with weakness on the fracture side with a dislocation rate of 1.0% (Group III), and 984 patients had severe dementia with a dislocation rate of 1.8% (Group IV). The increased dislocation rate for those with Parkinson's disease was statistically significant (p=0.02) while none of the other neuromuscular conditions were statistically significant. Conclusion. Our study demonstrates an increased risk of dislocation after hemiarthroplasty for patients with Parkinson's disease in comparison to other groups. No increase was apparent for those with dementia or weakness from a previous stroke

Introduction and Objective. Dislocation of a hip hemiarthroplasty is a significant complication with a high mortality rate in elderly patients. Previous studies have shown a higher risk of dislocation in patients with neuromuscular conditions. In this study, we reviewed our larger cohort of patients to identify if there is a link between neuromuscular disorders and dislocation of hip hemiarthroplasty in patients with neuromuscular conditions. Materials and Methods. We have retrospectively analysed a single-centre data that was collected over 34 years for patients with intracapsular neck of femur fracture who underwent hip hemiarthroplasty. The study population was composed of four groups: patients with no neuromuscular disorders, patients with Parkinson's disease, patients with previous stroke, and patients with mental impairment. Results. A total of 3827 patients were included in the analysis. 3371 patients had no neuromuscular condition (Group I) with a dislocation rate of 1.1%. 219 patients had Parkinsonism (Group II) with a dislocation rate of 3.2%, 104 patients had a previous stroke with weakness on the fracture side with a dislocation rate of 1.0% (Group III), and 984 patients had severe mental impairment with a dislocation rate of 1.8% (Group IV). The increased dislocation rate for those with Parkinson's disease was statistically significant (p=0.02) while none of the other neuromuscular conditions were statistically significant. Conclusions. Our study has shown an increased risk of dislocation of hemiarthroplasty in patients with Parkinson's disease in comparison to other groups. No increase was apparent for patients with mental impairment or weakness from a previous stroke

Between 2016–2019, 4 patients developed hip infections post-hemiarthroplasty. However, between 2020–2021 (Covid-19 pandemic period), 6 patients developed hip infections following hip hemiarthroplasty. The purpose of the investigation is to establish the root causes and key learning from the incident and use the information contained within this report to reduce the likelihood of a similar incident in the future. 65 patients presented with a neck of femur fracture during Covid-19 pandemic period between 2020–2021, 26 had hip hemiarthroplasty of which 6 developed hip infections. Medical records, anaesthetic charts and post-hip infections guidelines from RCS and NICE were utilised. Proteus, Enterococci and Strep. epidermis were identified as the main organisms present causing the hip infection. The average number of ward moves was 4 with 90% of patients developing COVID-19 during their hospital stay. The chance of post-operative wound infection were multifactorial. Having had 5 of 6 patients growing enterococci may suggest contamination of wound either due to potential suboptimal hygiene measures, inadequate wound management /dressing, potential environmental contamination if the organisms (Vancomycin resistant enterococci) are found to be of same types and potential hospital acquired infection due to inadequate infection control measures or suboptimal hand hygiene practices. 3 of the 5 patients grew Proteus, which points towards suboptimal hygiene practices by patients or poor infection control practices by staff. Lack of maintenance of sterility in post op wound dressings alongside inexperience of the handling of post-operative wound in non-surgical wards; multiple ward transfers exceeding the recommended number according to trust guidelines especially due to pandemic isolation measures and COVID-19 infection itself had resulted in an increased rate of hip infections during the COVID-19 pandemic. Multidisciplinary team education and planned categorisation and isolation strategy is essential to minimise the rate of further hip infections during the pandemic period in future

Hemiarthroplasty is a common procedure that is an attractive alternative to total arthroplasty because it conserves natural tissue, allows for quicker recovery, and has a lower cost. One significant issue with hemiarthroplasties is that they lead to accelerated wear of the opposing native cartilage, likely due to the high stiffness of the implant. The purpose of this study was to investigate the range of currently available biomaterials for hemiarthroplasty applications. We employed a finite-element (FE) model of a radial head implant against the native capitellum as our joint model. The FE model was developed in ABAQUS v6.14 (Dassault Systèmes Simulia Corp., Providence, RI, USA). A solid axisymmetric concave implant with seven different materials and the native radial head were evaluated, six modelled as elastic materials with different Young's moduli (E) and Poisson's Ratios (ν), and one modelled as a Mooney-Rivlin hyperelastic material. The materials investigated were CoCr (E=230 GPa, ν = 0.3), PEEK (E=3.7 GPa, ν = 0.36), HDPE (E=2.7 GPa, ν = 0.42), UHMWPE (E=0.69 GPa, ν = 0.49), Bionate 75D (E=0.288 GPa, ν = 0.39), Bionate 55D (E=0.039 GPa, ν = 0.45), and Bionate 80A (modelled as a Mooney-Rivlin hyperelastic material). A load of 100 N was applied to the radius through the center of rotation representing a typical load through the radius. The variable of interest was articular contact stress on the capitellum. The CoCr implant had a maximum contact stress over 114% higher than the native radial head. By changing the material to lower the stiffness of the implant, the maximum contact stress was 24%, 70%, 105%, 111%, 113%, and 113% higher than the native radial head for Bionate 80A, Bionate 55D, Bionate 75D, UHMWPE, HDPE, and PEEK respectively. This work shows that lowering implant stiffness can reduce the contact stress on cartilage in hemiarthroplasty implants. By changing the material below a Young's modulus of ∼100 MPa elevated stresses on the capitellum can be markedly reduced and hence potentially reduce or prevent degenerative changes of the native articulating cartilage. Low stiffness implant materials are not a novel concept, but to date there have been few that investigate materials (such as Bionate) as a potential load bearing material for implant applications. Further work is required to assess the efficacy of these materials for articular bearing applications

Background. Hip Hemiarthroplasty is one of the commonest orthopaedic operation done in UK with recent NHFD data from 2017 report showing that 43% of the 77000 patients who presented to hospital had hemiarthroplasty. Literature suggests dislocation rate of 0.8% – 6.1% for Hip Hemiarthroplasty. Dislocation of hemiarthroplasty may lead to significant morbidity and mortality. Aim. To investigate if acetabular dysplasia has a significant association with hemiarthroplasty dislocation. Methodology. Retrospective multicentre review. Review of radiographs of patients receiving a hip hemiarthroplasty for a hip fracture measuring Acetabular index (sharp angle) and Lateral Centre edge angle(CEA). A large acetabular index and lower value for the center-edge angle suggest acetabular dysplasia. Measurements were made for 20 patients with dislocation and 20 patients without dislocation. Statistical assessment of the results with unpaired t test was performed. Results. Mean acetabular angle for those with dislocation was 42.65 degrees versus 37.8 for those without dislocation giving a p value of 0.000861. Mean Center-edge angle of those with dislocation was 26.1 degrees versus 37 for those without dislocation giving a p value of 0.000019. Conclusion. This study showed that the hemiarthroplasty dislocation group had higher acetabular index and Lower Center-edge angle compared to the hemiarthroplasty group without dislocation clearly demonstrating that acetabular dysplasia is implicated in the aetiology of hip hemiarthroplasty dislocation. Hence careful review of the pre-op X-rays for dysplastic features would benefit in making a sound management plan

Prosthetic joint infections (PJI) are devastating complications. Our knowledge on hip fractureassociated hemiarthroplasty PJI (HHA-PJI) is limited compared to elective arthroplasty. The goal of this study was to describe the epidemiology, risk factors, management, and outcomes for HHA-PJI. A population-based (465,000) multicentre retrospective analysis of HHAs between 2006-2018 was conducted. PJI was defined by international consensus and treatment success as no return to theatre and survival to 90 days after the initial surgical management of the infection. Univariate, survival and competing risk regression analyses were performed. 1852 HHAs were identified (74% female; age:84±7yrs;90-day-mortality:16.7%). Forty-three (2.3%) patients developed PJI [77±10yrs; 56% female; 90-day-mortality: 20.9%, Hazard-Ratio 1.6 95%CI 1.1-2.3,p=0.023]. The incidence of HHA-PJI was 0.77/100,000/year and 193/100,000/year for HHA. The median time to PJI was 26 (IQR 20-97) days with 53% polymicrobial growth and 41% multi-drug resistant organisms (MDRO). Competing risk regression identified younger age [Sub-Hazard-Ratio(SHR) 0.86, 95%CI 0.8-0.92,p<0.001], chronic kidney disease (SHR 3.41 95%CI 1.36-8.56, p=0.01), body mass index>35 (SHR 6.81, 95%CI 2.25-20.65, p<0.001), urinary tract infection (SHR 1.89, 95%CI 1.02-3.5, p=0.04) and dementia (SHR 9.4, 95%CI 2.89-30.58,p<0.001) as significant risk factors for developing HHA-PJI. When infection treatment was successful (n=15, 38%), median survival was 1632 days (IQR 829-2084), as opposed to 215 days (IQR 20-1245) in those who failed, with a 90-day mortality of 30%(n=12). There was no significant difference in success among debridement, excision arthroplasty or revision arthroplasty. HHA PJI is uncommon but highly lethal. All currently identified predictors are non-modifiable. Due to the common polymicrobial and MDRO infections our standard antibiotic prophylaxis may not be adequate HHA-PJI is a different disease compared to elective PJI with distinct epidemiology, pathogens, risk factors and outcomes, which require targeted research specific to this unique population

The current evidence favors replacement for the treatment of displaced femoral neck fractures in the older patients. Controversies remain whether total hip replacement (THR), or hemiarthroplasty (HA) would result in better outcomes. The purpose of this study is to compare the outcomes, and the complications in patients who underwent THR or HA for displaced femoral neck fractures. There were 345 consecutive patients who had undergone either a THR or HA at a single institution. THR was done in 137, and HA was done in 208 patients, respectively. Standard peri-operative data were collected. The mean values for the data in the THR group are: age 69 years, ASA 2.7, OR time was 99 minutes, estimated blood loss 354 ml, and the length of stay 8 days. The mean values for the data in the HA group are: age 75 years, ASA 3.0, OR time 88 minutes, estimated blood loss 200 ml, and the length of stay 10 days. The overall complications were 8.8% (THR), and 9.1% (HA), respectively. The mortality rates for the patients were: at the 1-year (9.5% THR vs 16.3% HA), at the 3-year (15.3% THR vs 24.0% HA), and at the 5-year (19.7% THR vs 26.9% HA), respectively. Our data demonstrated similar peri-operative data and short-term complications between the two groups. There was a difference in the mortality rates between the two groups at all 3-time intervals following the surgery. This could be a reflection of the patient selection bias for each of the operations

Joint hemiarthroplasty replaces one side of a synovial joint and is a viable alternative to total joint arthroplasty when one side of the joint remains healthy. Most hemiarthroplasty implants used in current clinical practice are made from stiff materials such as cobalt chrome or ceramic. The substitution of one side of a soft cartilage-on-cartilage articulation with a rigid implant often leads to damage of the opposing articular cartilage due to the resulting reductions in contact area and increases in cartilage stress. The improvement of post-operative hemiarthroplasty articular contact mechanics is of importance in advancing the performance and longevity of hemiarthroplasty. The purpose of the present study was to investigate the effect of hemiarthroplasty surface compliance on early in-vitro cartilage wear and joint contact mechanics. Cartilage wear tests were conducted using a six-station pin-on-plate apparatus. Pins were manufactured to have a hemispherical radius of curvature of 4.7 mm using either Bionate (DSM Biomedical) having varying compliances (80A [E=20MPa], 55D [E=35MPa], 75D [E=222MPa], n=6 for each), or ceramic (E=310GPa, n=5). Cartilage plugs were cored from fresh unfrozen bovine knee joints using a 20 mm hole saw and mounted in lubricant-containing chambers, with alpha calf serum diluted with phosphate buffer solution to a protein concentration of 17 g/L. The pins were loaded to 30N and given a stroke length of 10 mm for a total of 50,000 cycles at 1.2 Hz. Volumetric cartilage wear was assessed by comparing three-dimensional cartilage scans before and during wear testing. A two-way ANOVA was used for statistical analysis. To assess hemiarthroplasty joint contact mechanics, 3D finite element modelling (ABAQUS v6.12) was used to replicate the wear testing conditions. Cartilage was modeled using neo-Hookean hyper-elastic material properties. Contact area and peak contact stress were estimated. The more compliant Bionate 80A and 55D pins produced significantly less volumetric cartilage wear compared with the less compliant Bionate 75D and ceramic pins (p 0.05). In terms of joint contact mechanics, the more compliant materials (Bionate 80A and 55D) had significantly lower maximum contact stress levels compared to the less compliant Bionate 75D and ceramic pins (p < 0 .05). The results of this study show a relationship between hemiarthroplasty implant surface compliance and early in vitro cartilage wear, where the more compliant surfaces produced significantly lower amounts of cartilage wear. The results of the joint contact mechanics analysis showed that the more compliant hemiarthroplasty materials produced lower maximum cartilage contact stresses than the less compliant materials, likely related to the differences in wear observed. More compliant hemiarthroplasty surfaces may have the potential to improve post-operative cartilage contact mechanics by increasing the implant-cartilage contact area while reducing peak contact stress at the implant-cartilage interface, however, such materials must be resistant to surface fatigue and longer-term cartilage wear/damage must be assessed

Abstract. Objectives. Current use of hard biomaterials such as cobalt-chrome alloys or ceramics to articulate against the relatively soft, compliant native cartilage surface reduces the joint contact area by up to two thirds. This gives rise to high and abnormal loading conditions which promotes degradation and erosion of the mating cartilage leading to pain, stiffness, and loss of function. Biomimetic soft lubrication strategies have been developed by grafting hydrophilic polymers onto substrates to form a gel-type surface. Surface grafted gels mimic the natural mechanisms of friction dissipation in synovial joints, showing a promising potential for use in hemiarthroplasty. This project aims to develop implant surfaces with properties tailored to match articular cartilage to retain and promote natural joint function ahead of total joint replacement. Methods. Four different types of monomers were grafted in a one-step photopolymerisation procedure onto polished PEEK substrates. The functionalised surfaces were investigated using surface wettability, FTIR, and simplified 2D-tribometry tests against glass and animal cartilage specimens to assess their lubricity and mechanical properties for hemiarthroplasty articulations. Results. Polymer functionalised surfaces under different grafting conditions were assessed for their wettability, graft density and quality. A reduction in water contact angle from 90° to < 20° was seen for functionalised highly hydrophilic PEEK surfaces. Similarly a reduction in the coefficient of friction (and subsequently shear stresses acting on cartilage) of 95% to ∼ 10. −2. was seen for functionalised PEEK surfaces slid against glass and cartilage in PBS. Conclusions. Development of this technology has the potential to vastly improve the performance of hemiarthroplasty. Providing earlier and targeted interventions for degenerative joint disease whilst preserving the function of the remaining healthy cartilage. Future work will concern using these promising hydrated functionalised surface architectures as focal cartilage deflects plugs along with long-term performance and suitability for implantation assessments using joint simulator testing

Recent NICE guidelines have suggested abandoning the Thompson hemiarthroplasty (TH) in favour of a ‘proven prosthesis’ such as the Exeter Trauma Stem (ETS). This is controversial because of significant cost implications and limited research assessing outcomes of the ETS. The aim of this study was to assess the treatment of intracapsular neck of femur fractures with the TH. Between 2002 and 2006 (minimum 5 year follow-up), 431 cemented TH's were performed. Death rate at 1 year and 5 years were 26.0% and 67.7% respectively. Dislocation (1.4%) and infection (0.2%) rates were low and revision rate was 1.2%. Comparison was made to Bipolar hemiarthroplasties over the same period (total 194). These had lower rates of dislocation (0.5%) and infection (0.5%) with a significantly higher (3.6%) revision rate. We feel that the TH remains the current gold standard treatment for intracapsular fractures, in appropriate patients, due to low complication and revision rates. Modern implants may provide better function or longevity, but there is no evidence in the literature to support abandoning the TH. Surgeons should assess patients and decide on its use, despite NICE guidelines, as it remains a cost effective treatment method, particularly for older, less mobile and cognitively impaired patients

Abstract. Background. To determine the long-term survival outcomes of Copeland Resurfacing Hemiarthroplasty (CRHA) performed by a single surgeon series. Methods. A retrospective cohort study which looked at patients who underwent CRHA over 6 years. Re-operations including revisions with component exchange taking place in our hospital and at local centres were reviewed. Oxford Shoulder Score (OSS) was used to assess their functional outcomes pre- and post-CRHA. Results. 80 CRHAs were performed in 72 patients between 2007 and 2013 with a mean follow-up of 6.5 years. The mean follow-up was 79 months (50–122). The primary indication for CRHA was osteoarthritis (76.3%), cuff tear arthropathy (16.3%), rheumatoid arthritis (5%) and post-trauma (1.3%). The mean pre-operative OSS was 16, which doubled following CRHA surgery. Fifteen patients underwent revision surgery due to ongoing glenoid pain with a mean revision time following primary CRHA being 49 months. Projected survival at the endpoints 5,7 and 10 years were 83, 81 and 79% respectively. Conclusion. This study provides us with a much longer average follow-up period in comparison to many other studies published. Previous studies, support resurfacing as a useful implant in reducing pain and improving function in the short-term; but this series demonstrates over the medium-term a relatively high revision rate of about 20% in comparison with other arthroplasty options, despite the revision rate seeming to plateau from the 5-year mark onwards

Gram-negative prosthetic joint infections (GN-PJI) present unique challenges in management due to their distinct pathogenesis of biofilm formation on implant surfaces. To date, there are no animal models that can fully recapitulate how a biofilm is challenged in vivo in the setting of GN-PJI. The purpose of this study is to establish a clinically representative GN-PJI in vivo model that can reliably depict biofilm formation on titanium implant surface. We hypothesized that the biofilm formation on the implant surface would affect the ability of the implant to be osseointegrated. The model was developed using a 3D-printed, medical-grade titanium (Ti-6Al-4V), monoblock, cementless hemiarthroplasty hip implant. This implant was used to replace the femoral head of a Sprague-Dawley rat using a posterior surgical approach. To induce PJI, two bioluminescent Pseudomonas aeruginosa (PA) strains were utilized: a reference strain (PA14-lux) and a mutant strain that is defective in biofilm formation (DflgK-lux). PJI development and biofilm formation was quantitatively assessed in vivo using the in vivo imaging system (IVIS), and in vitro using the viable colony count of the bacterial load on implant surface. Magnetic Resonance Imaging (MRI) was acquired to assess the involvement of periprosthetic tissue in vivo, and the field emission scanning electron microscopy (FE-SEM) of the explanted implants was used to visualize the biofilm formation at the bone-implant interface. The implant stability, as an outcome, was directly assessed by quantifying the osseointegration using microCT scans of the extracted femurs with retained implants in vitro, and indirectly assessed by identifying the gait pattern changes using DigiGaitTM system in vivo. A localized prosthetic infection was reliably established within the hip joint and was followed by IVIS in real-time. There was a quantitative and qualitative difference in the bacterial load and biofilm formation between PA14 and DflgK. This difference in the ability to persist in the model between the two strains was reflected on the gait pattern and implant osseointegration. We developed a novel uncemented hip hemiarthroplasty GN-PJI rat model. This model is clinically representative since animals can bear weight on the implant. PJI was detected by various modalities. In addition, biofilm formation correlated with implant function and stability. In conclusion, the proposed in vivo GN-PJI model will allow for more reliable testing of novel biofilm-targeting therapetics