Aims. Postoperative malalignment of the femur is one of the main complications in distal femur fractures. Few papers have investigated the impact of intraoperative malalignment on postoperative function and bone healing outcomes. The aim of this study was to investigate how intraoperative fracture malalignment affects postoperative bone healing and functional outcomes. Methods. In total, 140 patients were retrospectively identified from data obtained from a database of hospitals participating in a trauma research group. We divided them into two groups according to coronal plane malalignment of more than 5°: 108 had satisfactory fracture alignment (< 5°, group S), and 32 had unsatisfactory alignment (> 5°, group U). Patient characteristics and injury-related factors were recorded. We compared the rates of nonunion, implant failure, and reoperation as healing outcomes and Knee Society Score (KSS) at three, six, and 12 months as functional outcomes. We also performed a sub-analysis to assess the effect of fracture malalignment by plates and nails on postoperative outcomes. Results. The rates of nonunion and reoperation in group U were worse than those in group S (25.0% vs 14.3%; 15.6% vs 5.6%), but the differences were not significant (p = 0.180 and p = 0.126, respectively). Mean KSS in group U at all follow-up periods was significantly worse that in group S (75.7 (SD 18.8) vs 86.0 (SD 8.7); p < 0.001; 78.9 (SD 17.2) vs 89.1 (SD 9.8); p < 0.001; 85.0 (SD 11.9) vs 91.1 (SD 7.2); p = 0.002, respectively). In the sub-analysis of plates, mean KSS was significantly worse in group U at three and six months. In the sub-analysis of nails, the rate of reoperation was significantly higher in group U (28.6% vs 5.8%; p = 0.025), and mean KSS at six and 12 months was significantly worse in Group U. Conclusion. To obtain good postoperative functional results, intraoperative alignment of the coronal plane should be accurately restored to less than 5°. Cite this article: Bone Jt Open 2022;3(2):165–172

Aims. Femoral bone preparation using compaction technique has been shown to preserve bone and improve implant fixation in animal models. No long-term clinical outcomes are available. There are no significant long-term differences between compaction and broaching techniques for primary total hip arthroplasty (THA) in terms of migration, clinical, and radiological outcomes. Methods. A total of 28 patients received one-stage bilateral primary THA with cementless femoral stems (56 hips). They were randomized to compaction on one femur and broaching on the contralateral femur. Overall, 13 patients were lost to the ten-year follow-up leaving 30 hips to be evaluated in terms of stem migration (using radiostereometry), radiological changes, Harris Hip Score, Oxford Hip Score, and complications. Results. Over a mean follow-up period of 10.6 years, the mean stem subsidence was similar between groups, with a mean of -1.20 mm (95% confidence interval (CI) -2.28 to -0.12) in the broaching group and a mean of -0.73 mm (95% CI -1.65 to 0.20) in the compaction group (p = 0.07). The long-term migration patterns of all stems were similar. The clinical and radiological outcomes were similar between groups. There were two intraoperative fractures in the compaction group that were fixed with cable wire and healed without complications. No stems were revised. Conclusion. Similar stem subsidence and radiological and clinical outcomes were identified after the use of compaction and broaching techniques of the femur at long-term follow-up. Only the compaction group had intraoperative periprosthetic femur fractures, but there were no long-term consequences of these. Cite this article: Bone Jt Open 2021;2(12):1035–1042

Introduction: Intraoperative femoral fractures occurring in cementless total hip replacement are not frequent. In a series of in 350 consecutive hip replacements 15 cases of fractures were recognized and included for this study. Materials and Methods: The fractures mainly occured during the femoral preparation rather than during the definitive stem impaction. Accurate reduction and stable internal fixation were considered necessary intraoperatively. Nevertheless in 4 cases the fixation of the stem was converted into a conventional cemented one. Postoperatively the patients were allowed to have an immediat full weight bearing on the operated side in 5 cases. The remainders (10 patients) had a delayed reloading on the lower limb. In this study the clinical and radiological results of the fracture group were compared to those of a control group of 15 patients. Results: One year after surgery the Harris Hip score was no significantly different between the groups. Postoperative complication rate (deep venous thrombosis, infection, dislocation) were not different between the groups. There was a significant increase of duration of the stay of the patient in the rehabilitation center (p=0.007) in the fracture group and the patient spend more time with the physiotherapist (p=0.001)as they left the center. The fracture rate was lower when the patients were operated by a senior surgeon (p=0.021). Discussion: These results are comparable to those of the literature. Nevertheless intraoperative fractures of the proximal femur occurring in cementless total hip replacement do not jeopardize the clinical final outcome. This study emphasizes the importance of the learning–curve in cementless THR. Additional studies could assess the real costs for the medical care of such fractures

Aims

There is compelling evidence for the use of cemented hip hemiarthroplasty for displaced intracapsular hip fractures; however, the risks of cement are well reported and in rare cases may be associated with haemodynamic collapse. It is therefore important to improve our understanding of haemodynamic instability, intraoperative monitoring, and strategies to reduce the risk to patients.

Intraoperative fractures although rare are one of the complications known to occur while performing a total hip arthroplasty (THA). However, due to lower incidence rates there is currently a gap in this area of literature that systematically reviews this important issue of complications associated with THA. Method: We looked into Electronic databases including PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), the archives of meetings of orthopaedic associations and the bibliographies of included articles and asked experts to identify prospective studies, published in any language that evaluated intra-operative fractures occurring during total hip arthroplasty from the year 1950-2020. The screening, data extraction and quality assessment were carried out by two researchers and if there was any discrepancy, a third reviewer was involved. Fourteen studies were identified. The reported range of occurrence of fracture while performing hip replacement surgery was found to be 0.4-7.6%. Major risk factors identified were surgical approaches, Elderly age, less Metaphyseal-Diaphyseal Index score, change in resistance while insertion of the femur implants, inexperienced surgeons, uncemented femoral components, use of monoblock elliptical components, implantation of the acetabular components, patients with ankylosing spondylitis, female gender, uncemented stems in patients with abnormal proximal femoral anatomy and with cortices, different stem designs, heterogeneous fracture patterns and toothed design. Intraoperative fractures during THA were managed with cerclage wire, femoral revision, intramedullary nail and cerclage wires, use of internal fixation plates and screws for management of intra operative femur and acetabular fractures. The main reason for intraoperative fracture was found to be usage of cementless implants but planning and timely recognition of risk factors and evaluating them is important in management of intraoperative fractures. Adequate surgical site exposure is critical especially during dislocation of hip, reaming of acetabulum, impaction of implant and preparing the femoral canal for stem insertion. Eccentric and increased reaming of acetabulum to accommodate a larger cup is to be avoided, especially in females and elderly patients as the acetabulum is thinner. However, this area requires more research in order to obtain more evidence on effectiveness, safety and management of intraoperative fractures during THA

Aims. Breast cancer survivors have known risk factors that might influence the results of total hip arthroplasty (THA) or total knee arthroplasty (TKA). This study evaluated clinical outcomes of patients with breast cancer history after primary THA and TKA. Methods. Our total joint registry identified patients with breast cancer history undergoing primary THA (n = 423) and TKA (n = 540). Patients were matched 1:1 based upon age, sex, BMI, procedure (hip or knee), and surgical year to non-breast cancer controls. Mortality, implant survival, and complications were assessed via Kaplan-Meier methods. Clinical outcomes were evaluated via Harris Hip Scores (HHSs) or Knee Society Scores (KSSs). Mean follow-up was six years (2 to 15). Results. Breast cancer patient survival at five years was 92% (95% confidence interval (CI) 89% to 95%) after THA and 94% (95% CI 92% to 97%) after TKA. Breast and non-breast cancer patients had similar five-year implant survival free of any reoperation or revision after THA (p ≥ 0.412) and TKA (p ≥ 0.271). Breast cancer patients demonstrated significantly lower survival free of any complications after THA (91% vs 96%, respectively; hazard ratio = 2 (95% CI 1.1 to 3.4); p = 0.017). Specifically, the rate of intraoperative fracture was 2.4% vs 1.4%, and venous thromboembolism (VTE) was 1.4% and 0.5% for breast cancer and controls, respectively, after THA. No significant difference was noted in any complications after TKA (p ≥ 0.323). Both breast and non-breast cancer patients experienced similar improvements in HHSs (p = 0.514) and KSSs (p = 0.132). Conclusion. Breast cancer survivors did not have a significantly increased risk of mortality or reoperation after primary THA and TKA. However, there was a two-fold increased risk of complications after THA, including intraoperative fracture and VTE. Cite this article: Bone Joint J 2024;106-B(4):365–371

The most common classification of periprosthetic femoral fractures is the Vancouver classification. The classification has been validated by multiple centers. Fractures are distinguished by location, stability of the femoral component, and bone quality. Although postoperative and intraoperative fractures are classified using the same three regions, the treatment algorithm is slightly different. Type A fractures involve the greater and lesser trochanter. Fractures around the stem or just distal to the stem are Type B and subcategorised depending on stem stability and bone quality. Type C fractures are well distal to the stem and are treated independent of the stem with standard fixation techniques. The majority of fractures are either B1 (stable stem) or B2 (unstable stem). The stem is retained and ORIF of the fracture performed for B1 fractures. B2 and B3 fractures require stem revision with primary stem fixation distal to the fracture. Intraoperative fractures use the same A, B, C regions but are subtyped 1–3 as cortical perforations, nondisplaced, and displaced unstable fractures, respectively. With the exception of A1 intraoperative fractures all other intraoperative fractures require surgical treatment. A recent publication utilizing a New York state registry highlighted the patient risk of mortality associated with periprosthetic hip fractures. One month, 6 month and 1 year mortality was 3.2%, 3.8% and 9.7%, respectively. The mortality risk was lower for periprosthetic fractures treated with ORIF at 1 and 6 months compared to fractures requiring revision total hip

Aims. Periprosthetic femoral fractures (PPF) are a serious complication of total hip arthroplasty (THA) and are becoming an increasingly common indication for revision arthroplasty with the ageing population. This study aimed to identify potential risk factors for PPF based on an analysis of registry data. Methods. Cases recorded with PPF as the primary indication for revision arthroplasty in the German Arthroplasty Registry (Endoprothesenregister Deutschland (EPRD)), as well as those classified as having a PPF according to the International Classification of Diseases (ICD) codes in patients’ insurance records were identified from the complete datasets of 249,639 registered primary hip arthroplasties in the EPRD and included in the analysis. Results. The incidence of PPFs was higher (24.6%; 1,483) than reported in EPRD annual reports listing PPF as the main reason for revision (10.9%; 654). The majority of fractures occurred intraoperatively and were directly related to the implantation process. Patients who were elderly, female, or had comorbidities were at higher risk of PPFs (p < 0.001). German hospitals with a surgical volume of < 300 primary procedures per year had a higher rate of PPFs (p < 0.001). The use of cemented and collared prostheses had a lower fracture risk PPF compared to uncemented and collarless components, respectively (both p < 0.001). Collared prostheses reduced the risk of PPF irrespective of the fixation method and hospital’s surgical volume. Conclusion. The high proportion of intraoperative fractures emphasises the need to improve surgeon training and surgical technique. Registry data should be interpreted with caution because of potential differences in coding standards between institutions. Cite this article: Bone Joint J 2021;103-B(4):650–658

Background. Core decompression (CD) is effective to relieve pain and delay the advent of total hip arthroplasty (THA) for osteonecrosis of the femoral head (ONFH). However, the influence of CD on the subsequent THA has not been determined yet. Methods. Literatures published up to and including November 2018 were searched in PubMed, Embase and the Cochrane library databases with predetermined terms. Comparative studies of the clinical outcomes between conversion to THA with prior CD (the Prior CD group) and primary THA (the Control group) for ONFH were included. Data was extracted systematically and a meta- analysis was performed. Results. Overall, five retrospective cohort studies with 110 hips in the Prior CD group and 237 hips in the Control group were included and all the studies were of high quality in terms of Newcastle-Ottawa Scale. No difference in the rate of revision between the two groups showed (RR=1.92, P=0.46) after a minimal two-year follow-up. Postoperative Harris Hip Score were similar between the two groups in all the five studies. Two groups went through similar blood loss (P=0.38). But the operative time in the Prior CD group with tantalum rob was longer than that in the Control group (P=0.006, P<0,001, respectively in two papers). Moreover, intraoperative fracture and osteolysis or radiolucent lines were more likely to occur in the Prior CD group, though there is not statistical difference (RR=7.05, P=0.08; RR=3.14, P=0.05, respectively). Conclusion. The present evidence indicated that prior CD has no inferior effect on the survivorship nor hip scores to the subsequent THA. The operative time in the Prior CD group with tantalum rob was longer than that in the Control group. Attention should also be paid on possible more intraoperative fracture and postoperative osteolysis or radiolucent lines. For any figures or tables, please contact authors directly

Background. Uncemented dual-tapered stems are a popular choice for primary total hip arthroplasty (THA). The purpose of this study was to examine long-term outcomes after primary THA utilizing a single dual-tapered stem. Patients and Methods. Utilizing our total joint registry, we retrospectively identified 1215 THAs (1055 patients) performed with an uncemented dual-tapered stem from 1998 to 2009. Mean age was 55 years, 70% were male, and mean BMI was 30 kg/m. 2. Mean follow-up was 10 years. Analysis included implant survivorship, clinical outcomes, and radiographic results. Results. Survivorship from stem revision for any reason was 99.0% at 5 years postoperatively and 98.4% at both 10 and 15 years. Survivorship from stem revision for aseptic loosening was 99.9% at 5-, 10-, and 15-years postoperatively. Survivorship from stem revision for periprosthetic fracture was 99.7%, 99.1%, and 98.9% at 5, 10, and 15 years postoperatively, respectively. In total, 18 (1.5%) stems underwent revision. Revisions were performed for periprosthetic fracture (10, 0.82%), infection (7, 0.58%), and aseptic loosening (1, 0.08%). Intraoperative fracture occurred in 58 (4.77%) THAs treated with cerclage wiring (52, 89.66%) or no treatment (6, 10.34%) and insertion of a standard prosthesis. At mean radiographic follow-up of 10 years, only 4 of 1084 (0.37%) stems with 1-year radiographic follow-up had any radiolucency around the proximal ongrowth coating, and only 1 (0.10%) of these had a circumferential radiolucent line (Gruen zones 1–14). Conclusions. This uncemented dual-tapered femoral stem is associated with excellent survivorship, reasonably low intraoperative fracture rate, and extremely low rates of revision for aseptic loosening, periprosthetic fracture, and infection when used for primary THA at long-term follow up. For any tables or figures, please contact the authors directly

Aims. Although good clinical outcomes have been reported for monolithic tapered, fluted, titanium stems (TFTS), early results showed high rates of subsidence. Advances in stem design may mitigate these concerns. This study reports on the use of a current monolithic TFTS for a variety of indications. Methods. A multi-institutional retrospective study of all consecutive total hip arthroplasty (THA) and revision total hip arthroplasty (rTHA) patients who received the monolithic TFTS was conducted. Surgery was performed by eight fellowship-trained arthroplasty surgeons at four institutions. A total of 157 hips in 153 patients at a mean follow-up of 11.6 months (SD7.8) were included. Mean patient age at the time of surgery was 67.4 years (SD 13.3) and mean body mass index (BMI) was 28.9 kg/m. 2. (SD 6.5). Outcomes included intraoperative complications, one-year all-cause re-revisions, and subsidence at postoperative time intervals (two weeks, six weeks, six months, nine months, and one year). Results. There were eight intraoperative complications (4.9%), six of which were intraoperative fractures; none occurred during stem insertion. Six hips (3.7%) underwent re-revision within one year; only one procedure involved removal of the prosthesis due to infection. Mean total subsidence at latest follow-up was 1.64 mm (SD 2.47). Overall, 17 of 144 stems (11.8%) on which measurements could be performed had >5 mm of subsidence, and 3/144 (2.1%) had >10 mm of subsidence within one year. A univariate regression analysis found that additional subsidence after three months was minimal. A multivariate regression analysis found that subsidence was not significantly associated with periprosthetic fracture as an indication for surgery, the presence of an extended trochanteric osteotomy (ETO), Paprosky classification of femoral bone loss, stem length, or type of procedure performed (i.e. full revision vs conversion/primary). Conclusion. Advances in implant design, improved trials, a range of stem lengths and diameters, and high offset options mitigate concerns of early subsidence and dislocation with monolithic TFTS, making them a valuable option for femoral revision. Cite this article: Bone Joint J 2020;102-B(2):191–197

Periprosthetic fractures after total hip arthroplasty lead to considerable morbidity in terms of loss of component fixation, bone loss and subsequent functional compromise. The prevention, early recognition and appropriate management of such fractures are therefore critical. The pathogenesis of periprosthetic factors is multi-factorial. There are a number of intrinsic patient influences such as poor bone stock, biomechanics and compliance. There are also a host of extrinsic factors over which the surgeon has more control. The key tenets for fracture avoidance include careful planning, identifying the risk, choosing the correct implant, understanding the anatomy, and using appropriate surgical technique. There are a number of recognised risk factors for periprosthetic hip fractures The prevalence of intraoperative fractures during total hip arthroplasty is higher in the patient with osteopenia / osteoporosis. Other conditions causing increased bone fragility, such as osteomalacia, Paget's disease, osteopetrosis, and osteogenesis imperfecta are also at a higher risk of intraoperative fracture. The use of more and more press fit cementless components has also increased the number of periprosthetic femoral fractures because of the force required to obtain such a fit. Complex deformities of the proximal femur, particularly when associated with a narrow medullary canal, may also increase the risk of intraoperative fractures. Revision surgery is associated with a higher risk of intraoperative fracture than primary hip replacement surgery. These fractures typically occur during hip dislocation, cement extraction, or reaming through old cement. Other risk factors for postoperative femoral fractures following total hip replacement include loosening of the prosthesis with cortical bone loss, local osteolysis, stress risers within the cortex, such as old screw holes, the ends of plates, or impingement of a loose stem against the lateral femoral cortex. The management of periprosthetic fractures requires appropriate preoperative imaging, planning and templating, the availability of the necessary expertise and equipment, and knowledge of the potential pitfalls so that these can be avoided both intraoperatively and in follow-up. There is a danger that these cases fall between the expertise of the trauma surgeon and that of the revision arthroplasty surgeon. The past two decades have afforded us clear treatment algorithms based on fracture location, component fixation and the available bone stock. We still nevertheless face the enduring challenge of an elderly population with a high level of comorbidity who struggle to rehabilitate after such injuries. Perioperative optimization is critical as we have seen prolonged hospital stays, high rates of systemic complications and a significant short term mortality in this cohort. We have also been presented with new difficult fracture patterns around anatomic cementless stems and in relation to tapered cemented and cementless stems, as well as biologically challenging transverse or oblique fractures at the tip of a stem. In many cases, fixation techniques are biomechanically and biologically doomed to fail and intramedullary stability, achieved through complex revision is required. The sequelae of periprosthetic fractures include the financial cost of fixation or revision surgery, the associated morbidity and mortality in an elderly frail population, the difficulty with mobilization if the patient cannot fully weight bear, and a poor functional outcome in a proportion of cases. The battle over which patients or fractures require fixation and which require revision surgery continues

Background. In recent years, ‘Get It Right First Time (GIRFT)’ have advocated cemented replacements in femoral part of Total hip arthroplasty (THA) especially in older patients. However, many studies were unable to show any difference in outcomes and although cemented prostheses may be associated with better short-term pain outcomes there is no clear advantage in the longer term. It is not clear when and why to do cemented instead of cementless. Aim. To assess differences in patient reported outcomes in uncemented THAs based on patient demographics in order to decide when cementless THA can be done safely. Method. Prospective data collection of consecutive 1079 uncemented THAs performed for 954 patients in single trust between 2010 and 2020. Oxford Hip Score (OHS) and complications were analysed against demographic variables (age, sex, BMI, ASA) and prosthesis features (femoral and acetabular size, offset and acetabular screws). Results. The mean pre-operative OHS was 14.6 which improved to 39.0 at 1 year follow up (P Value=0.000). There was no statistically significant difference between OHS outcome in patients aged over 70 versus younger groups. With a small number of revisable complications increase with age from 50s upwards. Male patients’ OHS score was on average 2.4 points higher than women. Men, however were 2.9 times more likely to experience fractures and high offset hips were 2.5 times more likely to experience dislocations. DAIR, intraoperative calcar fractures, post-operative fractures and dislocations were not associated with worse OHS. Patients with increased BMI had worse pre and post-operative hip functions yet, there was a significant multivariate association between increased BMI and increased improvement in OHS from pre-op to 1 year in women aged 55–80 and men under the age of 60. Femoral stem size increases with age but decreases in male patients over 80. There was no difference found in OHS between bilateral hip replacements and unilateral, nor was there any change found with laterality side of the replacement. Conclusions. This study suggests that ageing >70 is not associated with poorer outcomes despite small number of revisable complication rates that increase with age from 50 upwards. Men had marginally higher average OHS than women At 1 year. Higher BMI or ASA scores are associated with worse pre-operative hips and worse final outcome score. Despite this, the Delta OHS increases with increased BMI shown in the 55–80 year old female patients and male patients under 60. Key Words: THR, Uncemented, Oxford hip score, outcome

Aims. The aim of this meta-analysis was to compare the outcome of total elbow arthroplasty (TEA) undertaken for rheumatoid arthritis (RA) with TEA performed for post-traumatic conditions with regard to implant failure, functional outcome, and perioperative complications. Materials and Methods. We completed a comprehensive literature search on PubMed, Web of Science, Embase, and the Cochrane Library and conducted a systematic review and meta-analysis. Nine cohort studies investigated the outcome of TEA between RA and post-traumatic conditions. The preferred reporting items for systematic reviews and meta-analysis (Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)) guidelines and Newcastle-Ottawa scale were applied to assess the quality of the included studies. We assessed three major outcome domains: implant failures (including aseptic loosening, septic loosening, bushing wear, axle failure, component disassembly, or component fracture); functional outcomes (including arc of range of movement, Mayo Elbow Performance Score (MEPS), and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire), and perioperative complications (including deep infection, intraoperative fracture, postoperative fracture, and ulnar neuropathy). Results. This study included a total of 679 TEAs for RA (n = 482) or post-traumatic conditions (n = 197). After exclusion, all of the TEAs included in this meta-analysis were cemented with linked components. Our analysis demonstrated that the RA group was associated with a higher risk of septic loosening after TEA (odds ratio (OR) 3.96, 95% confidence interval (CI) 1.11 to 14.12), while there was an increased risk of bushing wear, axle failure, component disassembly, or component fracture in the post-traumatic group (OR 4.72, 95% CI 2.37 to 9.35). A higher MEPS (standardized mean difference 0.634, 95% CI 0.379 to 0.890) was found in the RA group. There were no significant differences in arc of range of movement, DASH questionnaire, and risk of aseptic loosening, deep infection, perioperative fracture, or ulnar neuropathy. Conclusion. The aetiology of TEA surgery appears to have an impact on the outcome in terms of specific modes of implant failures. RA patients might have a better functional outcome after TEA surgery. Cite this article: Bone Joint J 2019;101-B:1489–1497

Aims. Studying the indications for revision total hip arthroplasty (THA) may enable surgeons to change their practice during the initial procedure, thereby reducing the need for revision surgery. The aim of this study was to identify and describe the potentially avoidable indications for revision THA within five years of the initial procedure. Patients and Methods. A retrospective review of 117 patients (73 women, 44 men; mean age 61.5 years (27 to 88)) who met the inclusion criteria was conducted. Three adult reconstruction surgeons independently reviewed the radiographs and medical records, and they classified the revision THAs into two categories: potentially avoidable and unavoidable. Baseline demographics, perioperative details, and quality outcomes up to the last follow-up were recorded. Results. A total of 60 revision THAs (51.3%) were deemed potentially avoidable and 57 (48.7%) were deemed unavoidable. The following were identified as avoidable factors: suboptimal positioning of the acetabular component (29; 48%), intraoperative fracture or a fracture missed on an intraoperative radiograph (20; 33%), early (less than two weeks) aseptic loosening (seven; 11.7%), and symptomatic leg length discrepancy of > 1 cm (four; 6.7%). Conclusion. A surprisingly large proportion of acute revision THAs are potentially avoidable. Surgeons must carefully evaluate the indications for revision THAs in their practice and identify new methods to address these issues. Cite this article: Bone Joint J 2019;101-B(6 Supple B):97–103

Aims. Metaphyseal fixation during revision total knee arthroplasty (TKA) is important, but potentially difficult when using historical designs of cone. Material and manufacturing innovations have improved the size and shape of the cones which are available, and simplified the required bone preparation. In a large series, we assessed the implant survivorship, radiological results, and clinical outcomes of new porous 3D-printed titanium metaphyseal cones featuring a reamer-based system. Methods. We reviewed 142 revision TKAs in 139 patients using 202 cones (134 tibial, 68 femoral) which were undertaken between 2015 and 2016. A total of 60 involved tibial and femoral cones. Most cones (149 of 202; 74%) were used for Type 2B or 3 bone loss. The mean age of the patients was 66 years (44 to 88), and 76 (55 %) were female. The mean body mass index (BMI) was 34 kg/m. 2. (18 to 60). The patients had a mean of 2.4 (1 to 8) previous operations on the knee, and 68 (48%) had a history of prosthetic infection. The mean follow-up was 2.4 years (2 to 3.6). Results. Survivorship free of cone revision for aseptic loosening was 100% and survivorship free of any cone revision was 98%. Survivorships free of any revision and any reoperation were 90% and 83%, respectively. Five cones were revised: three for infection, one for periprosthetic fracture, and one for aseptic tibial loosening. Radiologically, three unrevised femoral cones appeared loose in the presence of hinged implants, while the remaining cones appeared stable. All cases of cone loosening occurred in patients with Type 2B or 3 defects. The mean Knee Society score (KSS) improved significantly from 50 (0 to 94) preoperatively to 87 (72 to 94) (p < 0.001). Three intraoperative fractures with cone impaction (two femoral, one tibial) healed uneventfully. Conclusion. Novel 3D-printed titanium cones, with a reamer-based system, yielded excellent early survivorship and few complications in patients with severe bone loss undergoing difficult revision TKA. The diversity of cone options, relative ease of preparation, and outcomes rivalling those of previous designs of cone support their continued use. Cite this article: Bone Joint J 2020;102-B(6 Supple A):107–115

Incidence of intraoperative fracture during cementless Total Hip Arthroplasty (THA) is increasing. This is attributed to factors such as an increase in revision procedures and the favour of cementless fixation. Intraoperative fractures often occur during the seating of cementless components. A surgical mallet and introducer are used to generate the large impaction forces necessary to seat the component, sometimes leading to excessive hoop strain in the bone. The mechanisms of bone strain during impaction are complex and occur over very short timeframes. For this reason experimental and simulation models often focus on strain shortly after the implant is introduced, or seat it quasi-statically. This may not produce a realistic representation of the magnitude of strain in the bone and dangerously under-represent fracture risk. This in-vitro study seeks to determine whether strain induced during impaction is similar both during the strike (dynamic strain) and shortly after the strike has occurred (post-strike strain). It is also asked whether post-strike strain is a reliable predictor of dynamic strain. A custom drop tower was used to seat acetabular components in 45 Sawbones models (SKU: 1522–02, Malmo, Sweden), CNC milled to represent the acetabular cavity. Ten strikes were used to seat each cup. 3 strike velocities (1.5 m/s, 2.75 m/s, 4 m/s) and 3 impact masses (600 g, 1.2 kg, 1.8 kg) were chosen to represent 9 different surgical scenarios. Two strain gages per Sawbone were mounted on the surface of the block, 2 mm from the rim of the cavity. Strain data was acquired at 50 khz. Each strain trace was then analysed to determine the peak dynamic strain during mallet strike and the static strain post-strike. A typical strain pattern was observed during seating. An initial pre-strike strain is followed by a larger dynamic peak as the implant is progressed into the bone cavity. Strain subsequently settles at a lower (tensile) value than peak dynamic post-strike, but higher than pre-strike strain. Over the 450 strikes conducted dynamic strain was on average 3.39 times larger than post-strike strain. A statistically significant linear relationship was observed between the magnitude of post-strike and dynamic strain (adjusted R. 2. =0.391, p<0.005). This indicates that, for a known scenario, post-strike strain can be used as an indicator for dynamic peak strain. However when only the maximum dynamic and post-strike strains were taken from across the 10 strikes used to seat the implant, the relationship between the two strains was not significant (R. 2. =0.300, p=0.73). This may be due to the fact that the two maximums did not often occur on the same strike. On average, max dynamic strain occurred 1.7 strikes after max post-strike strain. We conclude that peak dynamic strain is much larger than the strain immediately post-strike in a synthetic bone model. It is shown that post-strike strain is not a good predictor of dynamic strain when the max strain during any strike to seat the component is considered, or variables (such as mallet mass or velocity) are changed. It is important to consider dynamic strain in bone as well as post-strike strain in experimental or simulated bone models to ensure the most reliable prediction of fracture

Aims. Total ankle arthroplasty (TAA) surgery is complex and attracts a wide variety of complications. The literature lacks consistency in reporting adverse events and complications. The aim of this article is to provide a comprehensive analysis of each of these complications from a literature review, and to compare them with rates from our Unit, to aid clinicians with the process of informed consent. Patients and Methods. A total of 278 consecutive total ankle arthroplasties (251 patients), performed by four surgeons over a six-year period in Wrightington Hospital (Wigan, United Kingdom) were prospectively reviewed. There were 143 men and 108 women with a mean age of 64 years (41 to 86). The data were recorded on each follow-up visit. Any complications either during initial hospital stay or subsequently reported on follow-ups were recorded, investigated, monitored, and treated as warranted. Literature search included the studies reporting the outcomes and complications of TAA implants. Results. There were wound-healing problems in nine ankles (3.2%), superficial infection in 20 ankles (7.2%), and deep infection in six ankles (2.2%). Intraoperative fractures occurred in medial malleoli in 27 ankles (9.7%) and in lateral malleoli in four ankles (1.4%). Aseptic loosening and osteolysis were seen 16 ankles (5.8%). Fracture of the polyethylene component occurred in one ankle (0.4%) and edge-loading in seven ankles (2.5%). We observed medial gutter pain in 31 ankles (11.1%). The incidence of thromboembolism occurred in two ankles (0.7%). The results were found to be comparable to the previously reported complications of total ankle arthroplasty in the literature. Conclusion. Total ankle arthroplasty continues to evolve and improve the ankle function. Despite high overall complication rates with TAA surgery, most complications appear to be minor and do not affect final clinical outcome. Our results and literature review will help in the consent process and provide detailed complication rates for an informed consent. Cite this article: Bone Joint J 2018;100-B:1352–8

Introduction and Objectives: One of the complications of hip arthroplasty is intraoperative fractures of the femur. In this study, we reviewed the incidence of intraoperative fractures in 118 hip arthroplasty surgeries using a stem from Meridian Howmedica, Rutherford, New Jersey, in an attempt to analyse the risk factors for intra-operative fractures and their relationship to short-term radiographic characteristics of the prosthesis. Our aim is to determine if there are risk factors associated with a higher incidence of intraoperative fractures in the following categories: patient, shape and dimensions of the femur, and relative size of the implant with respect to the medullary cavity. We will also determine if short-term follow up of patients with fractures yields radiographic information to indicate early loosening of the prosthesis. Materials and Methods: We studied 118 implants from consecutive operations performed from January 1997 to December 2000. The following variables were evaluated: general patient factors; local factors (characteristics of the femur); previous treatments, degree of femoral osteoporosis, type of femur, cervicodiaphyseal angle, femoral flring, “canal flare index”, cortical index, canal width 20mm proximal to the lesser trochanter, at the lesser trochanter, and 20mm distal to the lesser trochanter, pre-operative proximal and distal measurement of the stem, and if this coincides with the actual size of the stem; intraoperative factors: type of anaesthesia, patient positioning, surgical approach, experience of the surgeon, surgical time, the need for transfusion and number of units, the use of prophylactic cerclage, detection and localization of the intraoperative femoral fracture, and treatment of the same when they occurred; postoperative radiographic factors: level of cutting femoral neck, orientation of the stem (varus or valgus), proximal and distal stem size, proximal and distal packing of the canal, and length of the neck of the head of the prosthesis; radiographic factors 12 months postoperatively: stem orientation (varus or valgus), rounding of the calcar, cortical thickening, osteolysis, osteopenia, the presence of a ledge, the presence of lines of sclerosis, sinking of the stem, loosening of the ball, and the type of integration of the stem into the bone. Results: Of the 118 cases that were studied, intraoperative fractures occurred in 13 cases, representing an incidence of 11.01%, a somewhat higher rate than others have reported. We analyzed the occurrence of fractures in relation to the different variables in our study. We found a higher incidence of fractures in type A femurs (p< 0.05) and in cases of greater proximal filling by the implant (p< 0.05). Discussion and Conclusions: Though our study is limited in number of patients and length of follow-up time, it has demonstrated that the incidence of intraoperative fractures is associated with a narrow metaphyseal medullary cavity and predominately with a type A femur, which is a femur with low “canal flare index” values. Furthermore, since the risk of fracture is greater when we attempt to significantly adjust the size of the pros-thesis to the metaphysis, the incidence of fractures was higher when proximal filling was higher. However, cases of prosthesis with fractures did not present with radiographic appearance after 12 months that was worse than those femurs that were not fractured

Fracture during total hip arthroplasty occurs partly because the acquisition of fixation at the time of stem implantation depends on the operator's experience and sensation due to the absence of definite criteria. Therefore, an objective evaluation method to determine whether the stem has been appropriately implanted is necessary. We clarified the relationship between the hammering sound frequency during stem implantation and internal stress in a femoral model, and evaluated the possible usefulness of hammering sound frequency analysis for preventing intraoperative fracture. Three types of cementless stem were used. Orthopedists performed stem insertion using a procedure similar to that employed in routine operation. Stress was estimated by finite element analysis using the hammering force calculated from the loading sensor as a loading condition, and frequency analysis of hammering sound data obtained using a microphone was performed (Fig. 1). Finite element analysis showed a decrease in the hammering sound frequency with an increase in the estimated maximum stress (Fig. 2, 3). When a decrease in frequency was observed, adequate hammering had already been performed to achieve press-fit stability. Therefore, there is a possibility that the continuation of hammering induces intraoperative fractures that become a problem. Based on the relationship between stress and frequency, the evaluation of changes in frequency may be useful for preventing the development of intraoperative fractures. When a decrease in frequency is observed, the hammering force should be reduced thereafter. Hammering sound frequency analysis may allow the prediction of bone fractures that can be visually confirmed, and may be a useful objective evaluation method for the prevention of intraoperative bone fracture