Within an ageing population, the morbidity and mortality burden of neck of femur fractures will only worsen. Financially incentivising acute Trusts via the Best Practice Tariff for inpatient care has yielded good results(1,2,3,4) but post-discharge care is still variable. Most importantly, restoring patients to their pre-fracture mobility is key to their quality of life(5,6) and reducing both readmissions to hospital(7,8) and expensive local authority residential care. Unfortunately, physiotherapist vacancies are in their thousands(9,10) leading to waiting times of around three months once discharged(11). In 2019, the Royal Derby Hospital created a novel Hip Fracture Patient Advocate (HFPA) to observe those who have fallen through gaps in community services. It involves monitoring patients’ progression, signposting to appropriate services, flagging issues to the responsible consultant and assisting in physical mobilisation. A retrospective review examined data from patients discharged to their own homes. This included demographics, residential status and mobility, both pre-fracture and at 120 days post-fracture. Mobility was classified into five categories, in line with the national hip fracture database. In 2018, of 238 patients, 41.2% returned to their baseline or increased mobility, and, after the introduction of the HFPA in 2019, this figure increased to 48.2%. In one year, there was a 7% increase in patients recovering their baseline mobility. This is a cost-effective intervention that can successfully improve mobility, leading to improved long-term outcomes. This includes the potential to reduce acute readmissions and the need for residential care, appealing to Integrated Care Boards. It also bridges the gap to primary care to optimise medical management and after further development, could be financially-incentivised via the Best Practice Tariff. Rather than thinking more expensive clinicians are required, this study proposes that a HFPA can garner better outcomes for both the patient and the wider system

Aims. Periprosthetic fracture and implant loosening are two of the major reasons for revision surgery of cementless implants. Optimal implant fixation with minimal bone damage is challenging in this procedure. This pilot study investigates whether vibratory implant insertion is gentler compared to consecutive single blows for acetabular component implantation in a surrogate polyurethane (PU) model. Methods. Acetabular components (cups) were implanted into 1 mm nominal under-sized cavities in PU foams (15 and 30 per cubic foot (PCF)) using a vibratory implant insertion device and an automated impaction device for single blows. The impaction force, remaining polar gap, and lever-out moment were measured and compared between the impaction methods. Results. Impaction force was reduced by 89% and 53% for vibratory insertion in 15 and 30 PCF foams, respectively. Both methods positioned the component with polar gaps under 2 mm in 15 PCF foam. However, in 30 PCF foam, the vibratory insertion resulted in a clinically undesirable polar gap of over 2 mm. A higher lever-out moment was achieved with the consecutive single blow insertion by 42% in 15 PCF and 2.7 times higher in 30 PCF foam. Conclusion. Vibratory implant insertion may lower periprosthetic fracture risk by reducing impaction forces, particularly in low-quality bone. Achieving implant seating using vibratory insertion requires adjustment of the nominal press-fit, especially in denser bone. Further preclinical testing on real bone tissue is necessary to assess whether its viscoelasticity in combination with an adjusted press-fit can compensate for the reduced primary stability after vibratory insertion observed in this study. Cite this article: Bone Joint Res 2024;13(6):272–278

Aims. The aim of the study was to investigate whether the primary stability of press-fit acetabular components can be improved by altering the impaction procedure. Methods. Three impaction procedures were used to implant acetabular components into human cadaveric acetabula using a powered impaction device. An impaction frequency of 1 Hz until complete component seating served as reference. Overimpaction was simulated by adding ten strokes after complete component seating. High-frequency implantation was performed at 6 Hz. The lever-out moment of the acetabular components was used as measure for primary stability. Permanent bone deformation was assessed by comparison of double micro-CT (µCT) measurements before and after impaction. Acetabular component deformation and impaction forces were recorded, and the extent of bone-implant contact was determined from 3D laser scans. Results. Overimpaction reduced primary acetabular component stability (p = 0.038) but did not significantly increase strain release after implantation (p = 0.117) or plastic deformations (p = 0.193). Higher press-fits were associated with larger polar gaps for the 1 Hz reference impaction (p = 0.002, R. 2. = 0.77), with a similar trend for overimpaction (p = 0.082, R. 2. = 0.31). High-frequency impaction did not significantly increase primary stability (p = 0.170) at lower impaction forces (p = 0.001); it was associated with smaller plastic deformations (p = 0.035, R. 2. = 0.34) and a trend for increased acetabular component relaxation between strokes (p = 0.112). Higher press-fit was not related to larger polar gaps for the 6 Hz impaction (p = 0.346). Conclusion. Overimpaction of press-fit acetabular components should be prevented since additional strokes can be associated with increased bone damage and reduced primary stability as shown in this study. High-frequency impaction at 6 Hz was shown to be beneficial compared with 1 Hz impaction. This benefit has to be confirmed in clinical studies. Cite this article: Bone Joint J 2023;105-B(3):261–268

Hip prosthetic joint infection (PJI) is a debilitating complication following joint replacement surgery, with significant impact on patients and healthcare systems. The INFection ORthopaedic Management: Evidence into Practice (INFORM:EP) study, builds upon the 6-year INFORM programme by developing evidence-based guidelines for the identification and management of hip PJI. A panel of 21 expert stakeholders collaborated to develop best practice guidelines based on evidence from INFORM \[1\]. An expert consensus process was used to refine guidelines using RAND/UCLA criteria. The guidelines were then implemented over a 12-month period through a Learning Collaborative of 24 healthcare professionals from 12 orthopaedic centres in England. Qualitative interviews were conducted with 17 members of the collaborative and findings used to inform the development of an implementation support toolkit. Patient and public involvement contextualised the implementation of the guidelines. The study is registered with the ISCRTN (34710385). The INFORM guidelines, structured around the stages of PJI management, were largely supported by surgeons, although barriers included limited awareness among non-surgical team members, lack of job planning for multidisciplinary teams, and challenges in ensuring timely referrals from primary care. Psychological support for patients was identified as a critical gap. Advanced Nurse Practitioners and multidisciplinary team (MDT) coordinators were seen as potential bridges to address these knowledge gaps. The guidelines were also viewed as a useful tool for service development. This study presents the first evidence-based guidelines for hip PJI management, offering a comprehensive approach to prevention, treatment, and postoperative care. Effective implementation is crucial, involving wider dissemination amongst primary and community care, as well as non-specialist treatment centres. Further resources are needed to ensure job planning for MDTs and psychological support for patients. Overall, this study lays the foundation for improved PJI management, benefiting patients and healthcare systems

Aims. Cementless acetabular components rely on press-fit fixation for initial stability. In certain cases, initial stability is more difficult to obtain (such as during revision). No current study evaluates how a surgeon’s impaction technique (mallet mass, mallet velocity, and number of strikes) may affect component fixation. This study seeks to answer the following research questions: 1) how does impaction technique affect a) bone strain generation and deterioration (and hence implant stability) and b) seating in different density bones?; and 2) can an impaction technique be recommended to minimize risk of implant loosening while ensuring seating of the acetabular component?. Methods. A custom drop tower was used to simulate surgical strikes seating acetabular components into synthetic bone. Strike velocity and drop mass were varied. Synthetic bone strain was measured using strain gauges and stability was assessed via push-out tests. Polar gap was measured using optical trackers. Results. A phenomenon of strain deterioration was identified if an excessive number of strikes was used to seat a component. This effect was most pronounced in low-density bone at high strike velocities. Polar gap was reduced with increasing strike mass and velocity. Conclusion. A high mallet mass with low strike velocity resulted in satisfactory implant stability and polar gap, while minimizing the risk of losing stability due to over-striking. Extreme caution not to over-strike must be exercised when using high velocity strikes in low-density bone for any mallet mass. Cite this article: Bone Joint Res 2020;9(7):386–393

Partial thickness abductor tendon tears are a significant source of recalcitrant laterally based hip pain. For those that fail conservative treatment, the results of endoscopic repair are highly successful with minimal morbidity. The principal burden is the protracted rehabilitation that is necessary as part of the recovery process. There is a wide gap between failed conservative treatment and successful surgical repair. It is hypothesized that a non-repair surgical strategy, such as a bioinducitve patch, could significantly reduce the burden associated recovery from a formal repair. Thus, the purpose of this study is to report the preliminary results of this treatment strategy. Symptomatic partial thickness abductor tendon tears are treated conservatively, including activity modification, supervised physical therapy and ultrasound guided corticosteroid injections. Beginning in January 2022, patients undergoing hip arthroscopy for intraarticular pathology who also had persistently symptomatic partial thickness abductor tendon tears, were treated with adjunct placement of a bioinducitve (Regeneten) patch over the tendon lesion from the peritrochanteric space. The postop rehab protocol is dictated by the intraarticular procedure performed. All patients are prospectively assessed with a modified Harris Hip Score (mHHS) and iHOT and the tendon healing response examined by ultrasound. Early outcomes will be presented on nine consecutive cases. Conclusions - Will be summarized based on the preliminary outcomes to be reported

This meta analysis address the relationship between infection developing after total hip arthroplasty (THA) and heterotopic ossification (HO). To identify the gaps in available knowledge, we screened for full-length peer-reviewed research articles listed in PubMed, Embase, and Web of Science over the past 20 years. The following search terms and Boolean operators were used: heterotopic ossification AND infection AND (hip replacement OR hip arthroplasty). The search resulted in the identification of as few as 14 articles describing periprosthetic joint infection (PJI) and HO after THA. Data summarized from 6 studies suitable for further meta-analysis yielded a cumulative sample size of 753 observations, with 186 recorded events of HO. The pooled RR was estimated at 2.22 (95% CI: 1.00 to 4.91, p = 0.0497), suggesting a more than twofold risk of HO compared to the group without PJI. In conclusion, there is a clear association between a higher risk of HO and PJI. Basic research findings support the hypothesis that bacterial pathogen-associated molecular patterns (PAMPs) can lead to osteogenesis through a toll-like receptor (TLR) and nuclear factor kappa B (NF-κB) pathway in the course of HO development. Together, these results suggest that HO prophylaxis should always be prescribed in PJI after THA. Moreover, during revisions following THA for presumed non-septic reasons, the presence of HO warrants consideration for infection, as there is a potential heightened risk of pathologic ossification induced by PAMPs. Keywords: heterotopic ossification; total hip arthroplasty; total hip replacement; periprosthetic joint infection; bacteria. Authors Ł. Pulik and P. Łęgosz contributed equally to this work

The growth of life expectancy during the last decades has led to an increment in age-related conditions such as hip arthritis and fractures. On the other hand, these elderly patients will present a higher incidence of mental diseases which, in some studies, have been associated with inferior results. This study aims to evaluate the differences in early complication rates between patients with cognitive impairment compared with those without this condition following total hip replacement for osteoarthritis or fracture in the context of contemporary perioperative care protocols. We conducted a retrospective cohort study where cognitively-impaired patients who required primary hip arthroplasty were compared to a propensity-score matched cohort of patients without cognitive alterations. Early major complications were measured and analyzed in order to determine significant differences. Screening and matching. 1196 patients were identified during the study period. After screening for inclusion and exclusion criteria and matching, two cohorts comprising 65 patients each were compared. After performing the propensity-score match, no significant differences were found in covariates between the two groups. Outcomes. The occurrence of delirium was more frequent in patients with cognitive deficit (27.5%) than in the control group (9%), p<0.001. No significant differences were found among groups regarding myocardial infarction, venous thromboembolism, blood transfusion requirement, 30-day readmission, in-hospital death, 90-days death, dislocation or surgical site infection. The composite outcome of any adverse event did not exhibit a significant difference either. To our knowledge, this is the first study which demonstrates similar outcomes between patients with cognitive impairment and those without these alterations. Our results might indicate that contemporary protocols and implants are bridging the traditional gap between these two populations. These findings support the use of total hip arthroplasty in patients with mental alterations when indicated, especially in those institutions with strict perioperative protocols

The purpose of this modified Delphi study was to obtain consensus on wound closure (including best practices for each tissue layer of closure) and dressing management in total hip arthroplasty (THA), using an evidence-based approach. The Delphi panel included 20 orthopedic surgeons from Europe and North America. Eighteen statements were identified (14 specific to THA and 4 relating to both THA and total knee arthroplasty) using a targeted literature review. Consensus was developed on the statements with up to three rounds of anonymous voting per topic. Panelists ranked their agreement with each statement on a five-point Likert scale. An a priori threshold of 75% was required for consensus. In Round 1, 15 of 18 statements achieved consensus via a structured electronic questionnaire. In Round 2, the 3 statements that did not achieve consensus were revised during a virtual face to face meeting. An additional 2 statements were edited for clarity. In Round 3, the 5 revised statements achieved consensus via a structured electronic questionnaire. Wound closure related interventions that were recommended for use in THA included: 1) barbed sutures over non-barbed sutures (shorter closing times and overall cost savings); 2) subcuticular sutures over skin staples (lower risk of infections and higher patient preference); 3) mesh-adhesives over silver-impregnated dressings (lower rate of wound complications); 4) negative pressure wound therapy over other dressings (lower wound complications and reoperations and fewer dressing changes); 5) triclosan coated sutures (lower risk of surgical site infection). Using a modified Delphi approach, a panel of 20 orthopedic surgeons achieved consensus on 18 statements pertaining to multi-layer wound closure and dressing management in THA. This study forms the basis for identifying critical evidence gaps within wound management to help reduce variability in outcomes during THA

Aims. Precise implant positioning, tailored to individual spinopelvic biomechanics and phenotype, is paramount for stability in total hip arthroplasty (THA). Despite a few studies on instability prediction, there is a notable gap in research utilizing artificial intelligence (AI). The objective of our pilot study was to evaluate the feasibility of developing an AI algorithm tailored to individual spinopelvic mechanics and patient phenotype for predicting impingement. Methods. This international, multicentre prospective cohort study across two centres encompassed 157 adults undergoing primary robotic arm-assisted THA. Impingement during specific flexion and extension stances was identified using the virtual range of motion (ROM) tool of the robotic software. The primary AI model, the Light Gradient-Boosting Machine (LGBM), used tabular data to predict impingement presence, direction (flexion or extension), and type. A secondary model integrating tabular data with plain anteroposterior pelvis radiographs was evaluated to assess for any potential enhancement in prediction accuracy. Results. We identified nine predictors from an analysis of baseline spinopelvic characteristics and surgical planning parameters. Using fivefold cross-validation, the LGBM achieved 70.2% impingement prediction accuracy. With impingement data, the LGBM estimated direction with 85% accuracy, while the support vector machine (SVM) determined impingement type with 72.9% accuracy. After integrating imaging data with a multilayer perceptron (tabular) and a convolutional neural network (radiograph), the LGBM’s prediction was 68.1%. Both combined and LGBM-only had similar impingement direction prediction rates (around 84.5%). Conclusion. This study is a pioneering effort in leveraging AI for impingement prediction in THA, utilizing a comprehensive, real-world clinical dataset. Our machine-learning algorithm demonstrated promising accuracy in predicting impingement, its type, and direction. While the addition of imaging data to our deep-learning algorithm did not boost accuracy, the potential for refined annotations, such as landmark markings, offers avenues for future enhancement. Prior to clinical integration, external validation and larger-scale testing of this algorithm are essential. Cite this article: Bone Jt Open 2024;5(8):671–680

The 2020 London International Hamstring Consensus meeting was convened to improve our understanding and treatment of hamstring injuries. The multidisciplinary consensus panel included 14 International specialists on the management of hamstring injuries. The Delphi consensus process consisted of two rounds of surveys which were completed by 19 surgeons from a total of 106 participants. Consensus on individual statements was regarded as over 70% agreement between panel members. The consensus group agreed that the indications for operative intervention included the following: gapping at the zone of injury (86.9%); high functional demands of the patient (86.7%); symptomatic displaced bony avulsions (74.7%); and proximal free tendon injuries with functional compromise refractory to non-operative treatment (71.4%). Panel members agreed that surgical intervention had the capacity to restore anatomy and function, while reducing the risk of injury recurrence (86.7%). The consensus group did not support the use of corticosteroids or endoscopic surgery without further evidence. These guidelines will help to further standardise the treatment of hamstring injuries and facilitate decision-making in the surgical treatment of these injuries

Introduction. The anatomic dual mobility (ADM) technology utilized a monoblock cobalt chromium acetabular component. However, design limitations conferred difficulties controlling orientation during component insertion and inability to confirm full implant seating; the solution resulted in the creation of the modular dual mobility (MDM). The modular implant combines a standard titanium acetabular component and a cobalt chromium liner insert. Due to the metal-on-metal interface on MDM implants, fretting and corrosion releasing metal ions like previous metal-on-metal THA implants, were a concern. This study prospectively reviewed metal ions (cobalt, chromium and titanium) on patients who were at least 1 year post MDM implantation and compared them to patients with an ADM implant and evaluated radiographic seating of the components. Methods. All patients with ADM and MDM implants underwent evaluation of metal ions (cobalt, chromium and titanium) at their one year follow-up appointment. Radiographic evaluation for acetabular polar gaps was performed. Elevated metal ions were determined using standard laboratory ranges. Differences in baseline demographics were assessed using the Mann Whitney-U test and Fishers's exact test. Differences in metal ions and implant type were compared using the Fisher's exact tests. Results. Fifty consecutive patients (25 ADM and 25 MDM were included in the study. All patients in the ADM group were primary THR and all in the MDM group were revision THR. Mean age and BMI were 73 (+/−10) and 26 (+/−4) respectively. A majority of the participants were female (72%), overall mean length of implantation was 1.2 years. We found no difference in metal ion elevation between groups at a minimum of one year post implantation (cobalt, p=1.0, chromium, p=0.49; titanium p=1.0). Within the MDM and ADM cohorts, there were an equal number of patients with mildly elevated cobalt (n=6), as well as mildly elevated titanium (n=1). The ADM cohort had more patients with increased chromium when compared to the MDM cohort (ADM=1 vs MDM=0), but did not reach significance. There was one ADM patient with significantly elevated levels of cobalt and chromium probably related to prior spine fusion with dissimilar metal fixation. When reviewed as raw values, there was a difference in mean chromium levels between ADM and MDM cohorts (ADM=1.4 (+/− 2.5) vs MDM=1.2 (+/− 1.7), p=0.03; no other significant differences were found. An additional 32 ADM have been evaluated recently without elevation in cobalt or chromium levels. Of the total 55 ADM patients 4 had a 1mm polar gaps which filled in at 6–23 months postoperative. There were no polar gaps in the MDM series and one malseated liner. Conclusion. There were no significant differences in metal ion elevation minimum one year post implantation between primary ADM and revision MDM cohorts. This is encouraging based on the titanium/cobalt chrome interface in the MDM implant. Uncommon dome gaps in the monoblock ADM is not a clinical problem. For any tables or figures, please contact the authors directly

Introduction. Porous coated cups have a low modulus of elasticity that enhances press-fit and a surface that promotes osseointegration as well as permitting modularity. Monoblock ceramic acetabular cups represent a subtype of uncemented cup permitting the use of large femoral heads. The aim of this study was to compare the short-term clinical and radiographic performances of both cups. Methods. This was a prospective RCT of 86 unilateral THA patients (M: 40, F: 48; mean age: 59.5 ± 10.6) randomized to either a porous-coated, modular metal-on-polyethylene (MoP) acetabular component (pore size 250µm, 45% mean volume porosity)(n=46) or a hydroxyapatite (HA) and titanium-coated monoblock shell with ceramic-on-ceramic(CoC) bearing (pore size 300µm, 48% mean volume porosity & 80nm HA coating thickness)(n=42). All sockets were under-reamed by 1 mm. Two-year radiographs and patient-reported outcomes (PROMs) were available. Results. Thirty-two (69%) and 28 (6%) gaps were found in modular cup and monoblock groups, respectively (p=0.001). For the modular, 17 filled the gaps, whereas 15 turned into radiolucency; for the monoblock, 1 of the gaps turned into radiolucency at final follow-up (p<0.001). Complete shell-to-bone contact without radiolucent lines was seen in 30 (65%) porous-coated cups and in 41 (98%) HA shells (p<0.001). There were no associations between presence of lucent lines and PROMs (mHHS, WOMAC and UCLA) (p>0.05) in both groups. Modular cup group was an independent predictor of developing lucent lines (OR: 19.1, p= 0.007). No case underwent revision surgery due to acetabular loosening. There were 2 cases of squeaking in CoC monoblock shell with no functional limitations. Conclusion. Both cups showed successful clinical results at short-term follow-up; however, the porous-coated modular evidenced a significantly higher rate of radiolucent line occurrence, without any association with PROMs. Since these lines indicate the possibility of future cup loosening, longer follow-up is necessary. For any tables or figures, please contact the authors directly

Between January 1998 and December 1998, 82 consecutive patients (86 hips) underwent total hip arthroplasty using a trabecular metal monoblock acetabular component. All patients had a clinical and radiological follow-up evaluation at six, 12 and 24 weeks, 12 months, and then annually thereafter. On the initial post-operative radiograph 25 hips had a gap between the outer surface of the component and the acetabular host bed which ranged from 1 to 5 mm. All patients were followed up clinically and radiologically for a mean of 7.3 years (7 to 7.5). The 25 hips with the 1 to 5 mm gaps were studied for component migration at two years using the Einzel-Bild-Roentgen-Analyse (EBRA) digital measurement method. At 24 weeks all the post-operative gaps were filled with bone and no acetabular component had migrated. The radiographic outcome of all 86 components showed no radiolucent lines and no evidence of lysis. No acetabular implant was revised. There were no dislocations or other complications. The bridging of the interface gaps (up to 5 mm) by the trabecular metal monoblock acetabular component indicates the strong osteoconductive, and possibly osteoinductive, properties of trabecular metal

Objectives. Osteosynthesis of anterior pubic ramus fractures using one large-diameter screw can be challenging in terms of both surgical procedure and fixation stability. Small-fragment screws have the advantage of following the pelvic cortex and being more flexible. The aim of the present study was to biomechanically compare retrograde intramedullary fixation of the superior pubic ramus using either one large- or two small-diameter screws. Materials and Methods. A total of 12 human cadaveric hemipelvises were analysed in a matched pair study design. Bone mineral density of the specimens was 68 mgHA/cm. 3. (standard deviation (. sd). 52). The anterior pelvic ring fracture was fixed with either one 7.3 mm cannulated screw (Group 1) or two 3.5 mm pelvic cortex screws (Group 2). Progressively increasing cyclic axial loading was applied through the acetabulum. Relative movements in terms of interfragmentary displacement and gap angle at the fracture site were evaluated by means of optical movement tracking. The Wilcoxon signed-rank test was applied to identify significant differences between the groups. Results. Initial axial construct stiffness was not significantly different between the groups (p = 0.463). Interfragmentary displacement and gap angle at the fracture site were also not statistically significantly different between the groups throughout the evaluated cycles (p ⩾ 0.249). Similarly, cycles to failure were not statistically different between Group 1 (8438, . sd. 6968) and Group 2 (10 213, . sd. 10 334), p = 0.379. Failure mode in both groups was characterised by screw cutting through the cancellous bone. Conclusion. From a biomechanical point of view, pubic ramus stabilisation with either one large or two small fragment screw osteosynthesis is comparable in osteoporotic bone. However, the two-screw fixation technique is less demanding as the smaller screws deflect at the cortical margins. Cite this article: Y. P. Acklin, I. Zderic, S. Grechenig, R. G. Richards, P. Schmitz, B. Gueorguiev. Are two retrograde 3.5 mm screws superior to one 7.3 mm screw for anterior pelvic ring fixation in bones with low bone mineral density? Bone Joint Res 2017;6:8–13. DOI: 10.1302/2046-3758.61.BJR-2016-0261

Porous tantalum is a highly osteoinductive biomaterial, initially introduced in orthopedics in 1997, with a subsequent rapid evolution of orthopedic applications. The use of porous tantalum for the acetabular component in primary total hip arthroplasty (THA) has demonstrated excellent short-term and mid-term results. However, long term data are scarce. The purpose of this prospective study is to report the long-term clinical and radiological outcome following use of an uncemented porous tantalum acetabular component in primary THA with a minimum follow-up of 17.5 years, in a previously studied cohort of patients. We prospectively followed 128 consecutive primary THAs in 140 patients, between November 1997 and June 1999. A press-fit porous tantalum monoblock acetabular component was used in all cases. The presence of initial gaps in the polar region, as sign of incomplete seating of the monoblock cup, was assessed on the immediate postoperative radiographs. All patients were followed clinically and radiographically at 6, 12, and 24 weeks and 12 months and then at 2, 5, 8, 10, and 19 years, for a mean of 18.1 years (range 17.5 – 19 years). Periacetabular dome gap filling, acetabular cup migration and polyethylene wear were assessed by the EBRA digital measurement system, until 2 years postoperatively. Mean age of patients at the time of operation was 60.4 years old (range 24 – 72). Harris hip score, Oxford Hip Score and range of motion (ROM) were dramatically improved in all cases (p < 0.001). In the initial postoperative radiographs, periacetabular dome gaps were observed in the 15% of cases, and were progressively filled within 6 months. In 2 years postoperatively, the mean component migration, as shown in EBRA study, was 0.67 mm. At last follow-up, all cups were radiographically stable with no evidence of migration, gross polyethylene wear, progressive radiolucencies, osteolytic lesions or acetabular fractures. The survivorship with re-operation for any reason as end point was 92.8%, whereas the survivorship for aseptic loosening as an end point was 100%. Upon visual inspection, two removed acetabular components due to recurrent dislocation and infection, respectively, showed extensive bone osseointegration. In our primary THA series, the porous tantalum monoblock cup demonstrated excellent clinical and radiographic outcomes with no failures because of aseptic loosening at a mean follow-up of 18.1 years. Porous tantalum acetabular components showed excellent initial stability, produced less wear debris and revealed a great potential for bone ingrowth. Due to its unique osteoinductive properties and elliptical shape, porous tantalum monoblock cups have demonstrated superior short and long-term survivorship compared to other press fit prostheses in the market

Aims

To clarify the mid-term results of transposition osteotomy of the acetabulum (TOA), a type of spherical periacetabular osteotomy, combined with structural allograft bone grafting for severe hip dysplasia.

Introduction. The vast majority of intertrochanteric fractures treated with cephalomedullary nails (CMN) will heal. Occasionally even though bony union occurs excessive lag screw sliding can cause persistent pain and soft tissue irritation and return to surgery for hardware removal. The purpose of this study was to evaluate if fracture stability, lag screw tip-apex distance (TAD), and quality of reduction have any impact excessive lag screw sliding and potential cutout. Methods. As part of our level one trauma center's institutional hip fracture registry, a retrospective analysis identified 199 intertrochanteric fractures fixed with CMN between 2009 and 2015 with follow up to union or a minimum of three months. The mean follow-up was 22 months (3 to 94 months). Mean patient age was 75 years (50 to 97 years) and 72% were women. Postoperative radiographs were used to measure the TAD, quality of reduction, neck-shaft angle (NSA), and lateral lag screw prominence. Follow-up radiographs were reviewed to assess fracture union, translation, and progression of lateral lag screw prominence. Complications and reoperations were recorded. Results. The average lag screw sliding was 5±5 mm. Excessive lag screw sliding (defined as > 10 mm; one standard deviation above the mean) was present in 12% of patients. Lag screw sliding was more common in unstable fracture patterns (21% vs. 5%, p<0.01) and patients with calcar fracture gapping > 4 mm (26% vs. 4%, p<0.01). Lag screw sliding was not associated with age (p=0.9), sex (p=0.4), TAD (p=0.3), implant (p=0.8), distal interlocking screws (p=0.3), or NSA (p=0.2). There were seven (3%) patients with prominent lag screws that required removal. These patients experience more lag screw sliding than those that did not require removal (9 mm vs. 5 mm, p<0.01). The average TAD was 17±5 mm. 15 (7%) of patients had TAD of 25 mm or more. There were 2 cutouts (1%). The average TAD was larger in the cutout group (26 vs. 17 mm, p<0.01). Conclusion. In this series, the incidence of cutout was low and associated with a larger tip-apex distance. Excessive lag screw sliding was associated with unstable fracture patterns, calcar fracture gapping, and more reoperations for symptomatic hardware. Careful attention to calcar fracture reduction may minimize excessive lag screw sliding

Aims

Limited implant survival due to aseptic cup loosening is most commonly responsible for revision total hip arthroplasty (THA). Advances in implant designs and materials have been crucial in addressing those challenges. Vitamin E-infused highly cross-linked polyethylene (VEPE) promises strong wear resistance, high oxidative stability, and superior mechanical strength. Although VEPE monoblock cups have shown good mid-term performance and excellent wear patterns, long-term results remain unclear. This study evaluated migration and wear patterns and clinical and radiological outcomes at a minimum of ten years’ follow-up.

Periprosthetic femoral fractures are a challenging problem to manage. In the literature various constructs have been designed and tested, most requiring cables for proximal fixation. The Synthes Locking Attachment Plate (LAP) has been designed to achieve proximal fixation without the use of cables. The aim of this study was to biomechanically evaluate the LAP construct in comparison to a Cable plate construct, for the fixation of periprosthetic femoral fractures after cemented total hip arthroplasty (THA). Twelve synthetic femora were tested in axial compression, lateral bending and torsion to determine initial stiffness, and stiffness following fixation of a simulated midshaft fracture with and without a bone gap. Two different fracture fixation constructs (six per group) were assessed. Each construct incorporated a broad curved LCP with bi-cortical locking screws for distal fixation. In the Cable construct, 2 cables and 2 uni-cortical locking screws were used for proximal fixation. In the LAP construct, the cables were replaced by a LAP with 4 bicortical locking screws. Axial, lateral bending and torsional stiffness were assessed using intact specimen values as a baseline. Axial load to failure was also measured. The LAP construct was significantly stiffer than the cable construct under axial load with a bone gap (simulating a comminuted fracture) (p=0.01). There were no significant differences between the two constructs in any of the other modalities tested. Loading to failure resulted in no significant differences between constructs, in either initial stiffness or peak load. In conclusion the LAP construct enables bi-cortical screw fixation around a prosthesis. Compared to cables, this was stiffer when there was a bone gap and thus should offer improved proximal fixation of Vancouver B1 proximal femoral fractures in cemented THA