Aims. The aim of this study was to compare the functional and radiological outcomes in patients with a displaced fracture of the hip who were treated with a cemented or a cementless femoral stem. Patients and Methods. A four-year follow-up of a randomized controlled study included 141 patients who underwent surgery for a displaced femoral neck fracture. Patients were randomized to receive either a cemented (n = 67) or a cementless (n = 74) stem at hemiarthroplasty (HA; n = 83) or total hip arthroplasty (THA; n = 58). Results. Early differences in functional outcome, assessed using the Harris Hip Score, the Short Musculoskeletal Functional Assessment score and EuroQol-5D, with better results in cemented group, deteriorated over time and there were no statistically significant differences at 48 months. Two (3%) patients in the cemented group and five (6.8%) in the cementless group underwent further surgery for a periprosthetic fracture. This difference was statistically significant (p = 0.4). No patient underwent further surgery for instability or infection between one and four years postoperatively. The mortality and the radiological outcomes were similar in both groups. Conclusion. Patients with a displaced femoral neck fracture treated with an arthroplasty using a cemented or cementless stem had good function and few complications up to four years postoperatively. However, due to the poor short-term functional outcomes in the cementless group, the findings do not support their routine use in the treatment of these elderly patients. Cite this article: Bone Joint J 2018;100-B:1087–93

Background. Continual implant stability is an important factor for the long-term success of cementless hip replacements. The increasing lifespan of patients causes a higher frequency of osteoporosis which may result in implant loosening due to bone loss. This study aimed to evaluate stability of long living implants in patients with advanced age. Patients and methods. Nine cementless stems made of Titanium-alloy including adjacent bone tissue obtained post mortem were evaluated by radiologic-microradigraphical, histological and morphometrical analysis. The percentage of the surface area covered by bone (BICI=bone implant contact index) was determined. The age of seven women and two men ranged between 81 and 92 years. The time in situ ranged between 10 and 20 years. From the entire length of the femora bearing implants 5 transverse segments were excised, dehydrated, embedded in methylmethacrylate. After the grinding procedure, the sections were evaluated by light microscopy and morphometrical analysis. The autopsy findings were recorded. Atherosclerosis and their related diseases were evident in all cases. Results. The femora of all female patients revealed features of high bony atrophy with concomitant transformation of the corticalis into spongy bone, whereas in male patients minor to moderate atrophic bone changes in the proximal femoral area without implication of the corticalis could be observed. All of the cementless stems made of Titanium-alloy showed osteointegration. The stabilization of the implant resulted in the forceps-like encasement of the edges of the implant within the cortical anchoring and by the development of compensatory bony hypertrophy. The BICI ranged between 35 und 63 percent. Conclusion. Elderly patients provided with cementless hip replacments revealed stable implants in spite of marked bone atrophy and an implantation period up to 20 years. Simultaneously, severe atherosclerosis and their related diseases, which may contribute to bone loss, were evident. The present findings may result from the favoring properties of cementless endoprostheses made of titanium alloy, cortical prosthesis anchoring, and self regulating bone processes. Pharmacologic and therapeutic consequences together with geriatric assessment should be required to preserve functionality and mobility

Aim. In the last years, many short hip stem variants were developed, almost always sharing the principle of metaphyseal and proximal diaphyseal anchorage. In this study, we analyzed the midterm results after implanting short cementless hip stem of ESKA. Methods. A total of 380 total hip replacements using the ESKA-short cementless stems were performed in a series of 340 patients between November 2002 till May 2008. The clinical and radiological evaluation of the patients was done in September 2008. The mean follow up was 37 months (3–54 months). Results. The mean age of the patients was 65 years (35–85 years). The indications varied between osteoarthritis (n=342), avascular necrosis (n=23) and aseptic loosening of stem (n=15). Good clinical and radiological outcome without complications was observed in 361 cases. However, complications were recorded in 19 cases. Aseptic loosening was noted in 4 cases and was treated with stem exchange. Deep infection occurred in 5 cases, 3 of which had direct exchange and 2 had two-stage delayed reconstruction. Dislocation was noted in 2 cases, which were revisions after aseptic loosening. 8 patients suffered intraoperative femur fissures, 7 of which healed completely after prolonged partial weight bearing postoperatively (n=4 without osteosynthesis, n=3 needed adjunctive cerclage around the proximal femur). Only 1 spiral fracture was recorded and needed a periprosthetic NCB-plate. Conclusion. Our own experience with cementless short hip stems is, in accordance with other studies, also encouraging. Based on the metaphyseal and proximal diaphyseal anchorage, short stems established themselves as a surgical option in the hip replacement surgery. There was no increase in the postoperative complication rate compared with standard total hip arthoplasty. It is also an option for elderly population. However, long-term outcome is still to be investigated

We evaluated the results of Cementless Surface Replacement Arthroplasty (CSRA) of the shoulder in 67 patients with advanced glenohumeral destruction who have an intact rotator cuff. Between november 2002 and december 2008, 70 CSRA (32 Copeland/ Biomet and 38 SMRR/ Lima) were implanted in 67 patients. A deltopectoral approach was used in 34 cases and an anterosuperior approach in 36 cases. Patients were assessed using Constant score, a patient satisfaction score and a detailed radiographic analysis. The mean follow up was 3.4 years (range 1 to 7.5 years). The mean Constant score improved preoperatively from 17.6 points (range 2–55) to an average postoperative score of 66.1 (range 13–91). The pain score improved from 1.13 points (range 0–6) to 12.3 points (range 3–15). The forward flexion and external rotation improved from 71° (range 20 to 140) and 0° (range −40 to +45) to 143° (range 60 to180) and 34.4° (range −20 to +60) respectively. Complications included: 1 subscapularis detachment, 5 secondary rotator cuff tear, 1sepsis, 3 patients with shoulder stiffness. No shift in implant position was observed. 11 humeral components developed radiolucencies at the prosthesis-bone interface. The radiographic analysis involved a system of dividing the prosthesis/bone interface into 5 zones. The best clinical results were significantly achieved in patients with necrosis compared with osteoarthritis (Constant Score, ant. elevation, ext. Rotation). Using regression analysis we found that changes in the head-shaft angle position of the implant (valgus/varus placement of the CSRA) significantly predicted the age and sex adjusted Constant score. When the inclination angle of the humeral head decreases, the adjusted Constant score increases. In the same model, we also found that the lateral offset of the humerus significantly predicted the adjusted Constant score. When the lateral offset of the humerus decreases, the adjusted Constant score increases. The medialization of the glenoid significantly and negatively predicted the Constant score. Conclusion. CSRA of the shoulder outcomes have been comparable with those of stemmed arthroplasties. Radiolucent lines occur with follow up and most of the time located in the S1 area. Glenoid wear and humeral head lateralization negatively impact the clinical score. Cementless Shoulder resurfacing is a viable alternative to conventional shoulder arthroplasty

Introduction. Total Hip Arthroplasty (THA) in patients after proximal femoral osteotomy remains a major challenge. Inferior survival for both cementless and cemented THA has been reported in this subgroup of patients. Methods. We retrospectively evaluated the clinical and radiographic results of a consecutive series of 48 THAs (45 Patients) who had undergone conversion THA for failed intertrochanteric osteotomy after a mean of 12 years (2–33 years) using a cementless, grit-blasted, double-tapered femoral stem. Mean follow-up was 20 years (range, 15–25 years), mean age at surgery was 47 years (range, 13–55 years). Clinical results were evaluated using the Harris Hip Score. Kaplan-Meier survivorship analysis was performed to determine long-term outcomes for different end points. Results. At follow-up, 10 patients (11 hips) had died, and 1 patient (1 hip) was lost to follow-up. Five patients (5 hips) underwent femoral revision, 2 for infection and 3 for aseptic loosening of the stem. Overall stem survival was 91% at 20 years (95%-CI: 78%–97%); survival with femoral revision for aseptic loosening as end point was 93% (95%-CI: 80%–98%). Discussion and Conclusion. The long-term results with this type of cementless femoral component in young patients with failed intertrochanteric osteotomy are encouraging and compare well to those achieved in patients with regular femoral anatomy

Introduction. Modern cementless press fit stems rely on early fixation and stability for osteointegration and longterm success with early migration increasing the risk of failure. The Ein Bild Roentegen Analyse Femoral Component Analysis (EBRA-FCA) methods allow accurate measurement of femoral stem subsidence without the need for Tantalum markers. The degree of subsidence of femoral stems in the first two years has been shown to be highly predictive of failure when using the cut off value of 1.5 mm. We aimed to measure the early migration pattern of a titanium alloy, tapered, plasma and hydroxyapatite coated femoral stem and any factors associated with subsidence. Methods. Between January 2005-June 2007, 387 Accolade cementless femoral stems (Stryker, Allendale NJ) were implanted at our institution. Seventy-seven had a minimum of two years post operative follow up and a complete set of pre and postoperative radiographs for analysis. Our group inlcuded 45 females with a mean age of 71.4 years, and 32 males with a mean age of 68.5 years. The primary diagnosis was degenerative osteoarthritis in 71 patients, avascular necrosis in two, and post fracture in four patients. The average BMI was 27.1. We measured the canal index to assess bone quality and the canal calcar index to assess the proximal femoral morphology. Immediate postoperative radiographs were assessed for canal fill of the prosthesis and implantation varus/valgus angles. The EBRA-FCA software was used to obtain migration curves for each stem. Results. The mean follow up was 29.3months (24–48). The mean canal index was 0.55 (0.36–0.68) with a mean canal calcar index of 0.54 (0.39–0.79). The average canal fill index at the midpoint of the stem was <0.8 in 37 stems and >80 in 40 stems. The average subsidence at 24 months was 2 mm and this had risen to 2.4 mm by 36 months postoperatively. When analysed using a Kaplan Meier curve using 1.5 mm as an end point we found a survivorship of 63.4% (52.3–74.5) at 24 months and this had worsened to 41.6% (26.6–56.5) by 36 months. Multivariate and univariate regression analysis of measured variables did not reveal any significant hazard for any factor other than the larger stem sizes doing worse. Discussion. Although several cementless tapered stem designs have had an excellent track record, our migration analysis of the Accolade stem is somewhat concerning. Thirty three percent of stems had reached the 1.5 mm subsidence point by two years. This is of concern as work has previously shown this to predict failure of stems with aseptic loosening at ten years with an accuracy of 79%. If these stems go on to fail at the predicted rate this would represent an unacceptably high level of failure. Our data raises serious concerns about the overall clinical performance of this stem design due to poor initial stability and integration

INTRODUCTION. Cementless Total Hip Replacement surgery is a well established procedure for relative young patients with severe hip disease. Excellent long term clinical results have been published on the performance of the femoral component. With growing clinical experience, our concern focused on excessive wear of the Ultra High Molecular Weight Polyethylene (UHMWPE) ringloc liner of the Mallory Head cementless Total Hip Prosthesis. After its introduction in our clinic in 1997, this implant is still in use without any modification. We were concerned that due to premature liner wear, the performance of this implant would not be compliant with the international guideline on implant survival (NICE guidelines: at 10 year follow up, 90% of all implants should still be in situ). Our objective was to establish the amount of liner wear in our first 200 MH implants. METHODS. Our first 200 patients consecutively treated with Mallory Head prostheses were followed up to obtain a recent digital image. Follow up was complete for 181 (90.5%) of our 200 patients. Ten had died and nine were not able or willing to come for follow up. The mean duration of follow up was 8.3 years (range: 8–13). The 181 recent digital images were classified as either excessive wear or no excessive wear by two independent orthopedic surgeons. Next, liner wear was measured in the 2D frontal plane using PolyWare Pro/3D Digital Version Rev 5.1 software (Draftware Developers, Conway, USA). A threshold for excessive liner wear was set at 0.2mm/year, according to literature. RESULTS. Using software for measuring PE wear, 46.7% of all patients had excessive UHMWPE wear (> 0.2mm/yr). There was no relation between the amount of wear and BMI, gender, component size or the acetabular inclination angle. Thirteen patients (6.5%) were revised. Nine of these revisions were for excessive liner wear or aseptic loosening (4.5%). For now, our series of cementless Mallory Head prostheses is compliant with the NICE guideline on implant survival. However, with the measured amount of wear we expect to see a significant increase in the number of revisions for liner wear in the near future. DISCUSSION. Our clinical observation of premature UHMWPE wear proved correct. The measured amount of UHMWPE wear is consistent with the few other studies published on this subject. Although we present a retrospective study, limiting the strength of our results, we have included a large group of patients with acceptable loss to follow up. It is unclear if the observed wear will lead to a sharp increase in the number of revisions within the next few years. Possibly, future revisions will be complicated by loss of acetabular bone stock following the pathofysiological reaction to wear particles. Our results can probably be generalised for any district hospital

The concept of stainless steel dual mobility cups in total hip arthroplasty has demonstrated very low long-term instability rates and a 98% survival rate after 12 years. We systematically implanted titanium alloy acetabular cups during a one year period. The purpose of our retrospective study was to report the 18-year clinical outcome data in a homogeneous and continuous series of 103 primary total hip replacements after implantation of a cementless titanium cup. All patients were implanted with NOVAE Ti (SERF) cups made of titanium alloy combined with a retentive polyethylene liner and a 22.2 mm cobalt chrome prosthetic head. Mean patient age at the time of surgery was 53 years. All patients were clinically and radiographically evaluated. The overall 18-year actuarial cup survival rate with a 95% confidence interval was 87.4%. At last follow-up, there was no evidence of implant instability whereas acetabular aseptic loosening was reported in one case and high wear of the retentive liner in 9. The results of this investigation confirmed the long-term stability of dual-mobility implants. The main limitation of this system was early wear of the polyethylene liner in contact with the titanium metal back and reaction with third body along with loss of liner retentivity. In our study, titanium demonstrated favourable osteointegration properties but poor tribologic characteristics, therefore suggesting its interest at the bone-cup interface only

Aims. Periprosthetic femoral fractures (PFF) following total hip arthroplasty (THA) are devastating complications that are associated with functional limitations and increased overall mortality. Although cementless implants have been associated with an increased risk of PFF, the precise contribution of implant geometry and design on the risk of both intra-operative and post-operative PFF remains poorly investigated. A systematic review was performed to aggregate all of the PFF literature with specific attention to the femoral implant used. Patients and Methods. A systematic search strategy of several journal databases and recent proceedings from the American Academy of Orthopaedic Surgeons was performed. Clinical articles were included for analysis if sufficient implant description was provided. All articles were reviewed by two reviewers. A review of fundamental investigations of implant load-to-failure was performed, with the intent of identifying similar conclusions from the clinical and fundamental literature. Results. In total 596 articles were initially identified, with 34 being eligible for analysis. Aggregate analysis of 1691 PFFs in 342 719 primary THAs revealed a significantly higher number of PFFs with cementless femoral implants (p < 0.001). Single-wedge and double-wedge (fit-and-fill) femoral implants were associated with a threefold increase in PFF rates (p < 0.001) compared with anatomical, fully coated and tapered/rounded stems. Within cemented stems, loaded-taper (Exeter) stems were associated with more PFFs than composite-beam (Charnley) stems (p = 0.004). Review of the fundamental literature revealed very few studies comparing cementless component designs. Conclusion. Very few studies within the PFF literature provide detailed implant information. Cementless implants, specifically those of single-wedge and double-wedge, have the highest PFF rates in the literature, with most investigations recommending against their use in older patients with osteoporotic bone. This review illustrates the need for registries and future PFF studies to record implant name and information for future analysis. Furthermore, future biomechanical investigations comparing modern implants are needed to clarify the precise contribution of implant design to PFF risk. Cite this article: Bone Joint J 2017;99-B(1 Supple A):50–9

Aims

Periprosthetic fractures (PPFs) following hip arthroplasty are complex injuries. This study evaluates patient demographic characteristics, management, outcomes, and risk factors associated with PPF subtypes over a decade.

Introduction. Dislocation following total hip arthroplasty THA is a major short term complication not infrequently resulting in revision arthroplasty. Malposition of the acetabular component in THA results in a higher rate of dislocation as well as increased wear and osteolysis. The aim of this study was to assess the effect of mode of fixation on positioning of the acetabular component. Patients, materials and methods. For all THAs performed at our hospital in 2008, angle of acetabular inclination was measured using PACS by two independent observers. Interobserver and intraobserver reliability were assessed (Pearson's correlation coefficient, r). We determined whether the number of acetabular components outside the target angle range (eg:45±5°) was significantly different between cemented and cementless THA (chi squared test). An enquiry was made to the National Joint Registry (NJR) in respect to incidence of revision for dislocation of THA using cemented and cementless acetabular components, 2004–2009. Results. During 2008 126 THA were performed, 80 cemented and 46 cementless. There was good reliability of angle measurement (interobserver: r=0.89; intraobserver: r=0.87 and 0.97). More cemented acetabular components were within target angle range compared to cementless (cemented 32/80, cementless 29/46; chi squared=6.39, p<0.05). Using data from NJR comparing the number of primary hip replacement operations with number of revisions due to dislocation found a higher rate for cementless THA, 0.381% (266/69,822) than for cemented, 0.282% (262/92,928) (Odds ratio: 1.35 (95% CI 1.14–1.60; P<0.05). Conclusion. Positioning of the acetabular component is more difficult when using cementless systems as implant position is determined by orientation of reaming whereas with cement there is potential for fine implant position adjustment on insertion. The choice of a cementless acetabular component significantly increases the incidence of dislocation post THA. Acetabular component malposition is likely to be a factor in this increased incidence

Aims

The aim of this study was to investigate the rate of revision for distal femoral arthroplasty (DFA) performed as a primary procedure for native knee fractures using data from the Australian Orthopaedic Association National Joint Arthroplasty Registry (AOANJRR).

Aims

The aim of this study was to describe the demographic details of patients who sustain a femoral periprosthetic fracture (PPF), the epidemiology of PPFs, PPF characteristics, and the predictors of PPF types in the UK population.

The use of a total hip arthroplasty with alumina on alumina bearing couple should limit the risk of wear and secondary osteolysis. From June 1999 to December 2002, we have realised a continuous series of 265 ABGII cementless THA with Alumina bearing. The average age was 58 years (22–78 years). The main causes were osteoarthritis (81%) and osteonecrosis (13%). The operation was performed through a posterior standard approach. In all cases, an anatomic cementless ABG II stem and an acetabular cementless ABG II cup were implanted. The bearing couple was always Alumina Biolox Forte with a 28 mm femoral head in 99% of cases. To date, 12 patients died and 17 patients were lost to follow up (6.4%). 224 patients (232 hips) had a regular clinical and radiological follow-up. The mean follow up was 8.5 years (5–11 years). 9 patients were revised for septic loosening (4cases), femoral fracture (4 cases) and inveterate dislocation (1 case). There was no aseptic loosening. The overall survival rate at more than 10 years is 96.6%. We deplore 2 cases of postoperative dislocation. In this series, we did not observe any breakage of ceramic implant. The clinical and functional outcome is good and stable over time with an average PMA score at 17.6 and an average Harris score at 97.3. 16 patients reported at least one or more episode of abnormal noise “Squeaking” type (6%). It is most often a mild noise and it occurs in a static bending position. This noise disappeared with time in 10 cases. It never necessitated a prosthetic revision. The radiological control does not show any wear. There is no evidence of acetabular or femoral osteolysis. The radiological implant fixation according to the Engh and ARA criteria was good and stable in all cases. This series demonstrate that the implantation of an anatomic cementless HA arthroplasty with an alumina bearing in a young and active patient prevents the risk of wear and osteolysis and improves durability over time. The use of a 28 mm head does not increase the risk of instability and we did not observe failure of the ceramic implants

Introduction. Radiolucencies beneath the tibial component are well recognized in knee arthroplasty; the aetiology and significance are poorly understood. Non-progressive narrow radiolucencies with a sclerotic margin are thought not to be indicative of loosening. Factors which decrease the incidence of radiolucencies include cementless fixation and the use of pulse lavage. Leg/component alignment or BMI do not influence radiolucency. We are not aware of any studies that have looked at the effect of load type on radiolucency. The Oxford domed lateral tibial component was introduced to decrease the bearing dislocation rate that was unacceptably high with the flat tibial tray. However, the introduction of the domed tibial component alters the forces transmitted through the implant-cement-bone interface. As the Oxford UKR uses a fully congruent mobile bearing, the forces transmitted through the interface with a flat tray are compressive, except for the effect of friction. However, with the domed tibial component shear forces are introduced. The aim of this study was to assess the prevalence of radiolucency beneath the previous flat design and the new domed tibial tray. Patients and methods. A consecutive series of 248 cemented lateral UKRs (1999–2009) at a single institution were assessed. The first 55 were with a flat tibia and the subsequent 193 with a domed component. One year post-op radiographs were assessed, by two observers, for the presence (full or partial) and distribution of radiolucency. The distribution and thickness of each radiolucency. Cases were excluded for missing or poorly aligned radiographs. Results. In the flat group there were 42 patients (17 male, 25 female) with 42 joints. In the domed group there were 139 patients (44 male, 95 female) with 146 joints. There was a statistical significant difference between groups for the presence and extent of radiolucency (p<0.001). In the flat group, 6 (14%) had a full radiolucency and 18 (43%) had a partial radiolucency. 14 of the 18 partial radiolucencies involved the far lateral zones (1&2) and 3 partial radiolucencies involved the keel. In the domed group 6, (4.1%) had a full radiolucency and 13 (8.9%) had a partial radiolucency. All radiolucencies observed were less than 1 mm thick. Intra-class correlation for inter-observer agreement for assessment of radiolucency was 0.679. Discussion. The introduction the domed lateral tibial component results in a reduction in prevalence of radiolucency compared to a flat component. This suggests, as the mode of fixation is identical, that the forces across the tibial-cement-bone interface have a significant effect on the development of the tissue at that interface. In particular it suggests that compressive forces alone tend to cause soft tissue to be formed at the interface, whereas shear force causes bone

Background. An increasing number of hip prostheses are inserted without bone cement. Experimental research has shown that hydroxyapatite (HA) coated implants are strongly fixated in the bone, which is believed to reduce the likelihood of prosthetic loosening. However, in recent years, there has been much debate about the role of HA particles in third-body polyethylene (PE) wear and formerly we have shown the revision rate to be high among older-design HA coated cups. Purpose. We hypothesized increased PE wear-rate using HA coated acetabular components in comparison with non-HA coated components (control group). Materials and Methods. We performed a retrospective comparative clinical study based on two patient populations identified in the Danish Hip Arthroplasty Registry (October 2006). All patients had primary total hip arthroplasty (THA) between 1997 and 2001 with cementless Mallory-Head acetabular components. One group received HA coated acetabular components (75 patients, 77 hips). The other group received identical components without HA (70 patients, 73 hips). In all cases the liner was similar and 28 mm metal femoral heads were used. All patients were invited for a radiographic follow-up in 2007. The AP radiographs were analysed for two-dimensional (2D) polyethylene wear using the semi-automated PolyWare software. All cases of non-responders, stem revisions, hip dislocations and patients with less than 5 years of follow-up were excluded from the analysis. Findings/Results. The 2D linear PE wear-rate of 0.18 mm/year (SD 0.09) was higher (P<0.001) in the group with HA coated cups (n = 54) compared with 0.12 mm/year (SD 0.07) in the group of non-HA coated cups (n = 35). The Effect size of the difference in linear PE wear-rate, established as Cohen's d, was large (0.9). The time of follow-up was similar (p = 0.11) in the HA group (7.2 years) versus the non-HA group (7.6 years). There was no case-mix concerning distribution of gender and operated side in the groups; however, the mean age was lower (P = 0.001) in the HA group (57 years) compared with the non-HA group (63 years). Conclusions. We found a significantly increased PE wear rate in HA coated acetabular components at midterm follow-up. The patients with HA coated cups were younger on average, and this might partly explain the findings because the activity level expectedly is higher in younger patients. Still an effect size of 0.9 is large and should raise concern and supplement considerations in future clinical decisions on component selection. A randomized (RSA) study on newer type crosslinked polyethylene liners is recommended to bring about more information on the clinical performance and longevity of HA coated acetabular components

Introduction. The origins of the uncemented tapered wedge hip stem design currently offered by several orthopaedic device companies can be linked back to the cemented Straight Mueller type stem design first used in 1977. The design, a wedge shape with a taper angle of 6 degrees, maintains a single medial curvature for all sizes and increases laterally in the width to accommodate different size femurs. Although evolutionary improvements have been made over the years the basic body geometry of the stem has stayed mainly unchanged with excellent clinical survivorship. Over the past decade, the demographics of hip replacement have changed, with a large increase in younger male patients in the age range of 40 to 60 years. In this study the femoral fit of a novel tapered stem, designed to fit a wide array of patient types, is compared to a standard predicate tapered stem design. Methods. A bone morphology study was performed on a patient population of 556 patients using three dimensional digital data from CT-scans. To characterize the fit of the stem designs we analyzed the ratio of a distal (60mm below lesser trochanter) and a proximal (10mm above lesser trochanter) cross section. The same measurements were taken with the standard tapered stem design and the novel tapered stem design, with a given constant implantation height of 20mm above the lesser trochanter. The fit of the stems was classified as Type 1, where there was both proximal and distal engagement, Type 2, proximal engagement only, Type 3, distal engagement only. The distal and proximal engagement, Type 1, was specified with a maximum engagement difference of 2mm proximal to distal. Results. The standard tapered stem showed a well balanced distal to proximal ratio in the median sizes. However, with increasing stem size the distal engagement increases. The novel tapered stem design showed a well balanced proximal to distal ratio throughout the complete size range. With respect to Type 3 fit classification the novel tapered stem design showed a reduced percentage of distal engagements (2.8%) compared to the predicate standard stem (17.2%). In the 40 to 60 year old male group the distal engagements for the standard stem increases (28.2%), whereas the distal engagements for the novel stem remains unchanged (1.3%). Discussion. The cementless, tapered wedge stem design is used in large numbers globally due to its ease of use and reproducibility. However, changing patient demographics and associated bone morphology represents a challenge for existing designs to achieve a proximal fit. The novel tapered stem design presented here was adapted to these influencing factors by optimizing the proximal to distal ratio with respect to the whole patient group resulting in a particularly marked improvement in proximal fit in the male 40–60 age group compared to predicate stem designs

Aims

To evaluate the outcomes of cemented total hip arthroplasty (THA) following a fracture of the acetabulum, with evaluation of risk factors and comparison with a patient group with no history of fracture.

Objectives

The aim of this systematic literature review was to assess the clinical level of evidence of commercially available demineralised bone matrix (DBM) products for their use in trauma and orthopaedic related surgery.

Aims

A fracture of the hip is the most common serious orthopaedic injury, and surgical site infection (SSI) is one of the most significant complications, resulting in increased mortality, prolonged hospital stay and often the need for further surgery. Our aim was to determine whether high dose dual antibiotic impregnated bone cement decreases the rate of infection.