Objectives. Favourable results for collarless polished tapered stems have been reported, and cement creep due to taper slip may be a contributing factor. However, the ideal cement thickness around polished stems remains unknown. We investigated the influence of cement thickness on stem subsidence and cement creep. Methods. We cemented six collarless polished tapered (CPT) stems (two stems each of small, medium and large sizes) into composite femurs that had been reamed with a large CPT rasp to achieve various thicknesses of the cement mantle. Two or three tantalum balls were implanted in the proximal cement in each femur. A cyclic loading test was then performed for each stem. The migration of the balls was measured three-dimensionally, using a micro-computed tomography (CT) scanner, before and after loading. A digital displacement gauge was positioned at the stem shoulder, and stem subsidence was measured continuously by the gauge. Final stem subsidence was measured at the balls at the end of each stem. Results. A strong positive correlation was observed between mean cement thickness and stem subsidence in the CT slices on the balls. In the small stems, the balls moved downward to almost the same extent as the stem. There was a significant negative correlation between cement thickness and the horizontal:downward ratio of ball movement. Conclusion. Collarless polished tapered stems with thicker cement mantles resulted in greater subsidence of both stem and cement. This suggests that excessive thickness of the cement mantle may interfere with effective radial cement creep. Cite this article: E. Takahashi, A. Kaneuji, R. Tsuda, Y. Numata, T. Ichiseki, K. Fukui, N. Kawahara. The influence of cement thickness on stem subsidence and cement creep in a collarless polished tapered stem: When are thick cement mantles detrimental? Bone Joint Res 2017;6:–357. DOI: 10.1302/2046-3758.65.BJR-2017-0028.R1

Aims. The aim of this study is to report the long-term outcomes of instrumented femoral revisions with impaction allograft bone grafting (IBG) using the X-change femoral revision system at 30 years after introduction of the technique. Methods. We updated the outcomes of our previous study, based on 208 consecutive revisions using IBG and the X-change femoral revision system in combination with a cemented polished stem, performed in our tertiary care institute between 1991 and 2007. Kaplan-Meier survival analyses were used to determine the survival rate of the revisions with endpoint revision for any reason and aseptic loosening. Secondary outcomes were radiological loosening and patient-reported outcome measures. Results. Mean age at revision total hip arthroplasty (THA) was 64.9 years (30 to 86). The most prevalent diagnosis for the femoral revision was aseptic loosening. At review in May 2021, 81 patients (85 hips) were still alive and 118 patients (120 hips; 58%) had died. Three patients (3 hips; 1%) were lost to follow-up at 11, 15, and 16 years after surgery, respectively. Data of all deceased and lost patients were included until final follow-up. The mean follow-up was 13.4 years (0 to 28). During the follow-up, 22 re-revisions were performed. The most common reason for re-revision was infection (n = 12; 54%). The survival with endpoint re-revision for any reason was 86% (95% confidence interval (CI) 79 to 91) at 20 years and 74% (95% CI 43 to 89) at 25 years after surgery. The survival for endpoint re-revision for aseptic loosening was 97% (95% CI 91 to 99) after both 20 and 25 years. Conclusion. We conclude that femoral IBG is a valuable technique that can reconstitute femoral bone loss in the long term. After 25 years of follow-up, few re-revisions for aseptic loosening were required. Also, the overall revision rate is very acceptable at a long follow-up. This technique is especially attractive for younger patients facing femoral revisions with extensive bone loss. Cite this article: Bone Joint J 2022;104-B(9):1039–1046

We retrospectively reviewed 175 patients (191 hips) who had undergone primary cemented total hip replacement between November 1992 and November 1995 using a collarless polished double-tapered femoral component after a minimum of ten years (mean 11.08; 10 to 12.8). All stems were implanted using contemporary cementing techniques with a distal cement restrictor, pressurised lavage, retrograde cementing with a gun and proximal pressurisation. Clinical outcome was assessed using the Harris Hip score. Radiological analysis was performed on calibrated plain radiographs taken in two planes. Complete radiological data on 110 patients (120 hips) and clinical follow-up on all the surviving 111 patients (122 hips) was available. The fate of all the hips was known. At final follow-up, the mean Harris Hip score was 86 (47 to 100), and 87 of 116 patients (75%) had good or excellent scores. Survival with revision of the stem for aseptic loosening as the endpoint was 100%; and survival with revision of the stem for any reason was 95.9% (95% confidence interval 87.8 to 96.8) at ten years. All the stems subsided vertically at the stem-cement interface in a predictable pattern, at an overall mean rate of 0.18 mm per year (0.02 to 2.16), but with a mean rate of 0.80 mm (0.02 to 2.5) during the first year. The mean total subsidence was 1.95 mm (0.21 to 24). Only three stems loosened at the cement-bone interface. There was excellent preservation of proximal femoral bone stock. There was a high incidence of Brooker III and IV heterotopic ossification affecting 25 patients (22%). The collarless polished tapered stem has an excellent clinical and radiological outcome at a minimum of ten years’ follow-up. The pattern and magnitude of subsidence of the stem within the cement mantle occurred in a predictable pattern, consistent with the design philosophy

Aims. The aim of this large registry-based study was to compare mid-term survival rates of cemented femoral stems of different designs used in hemiarthroplasty for a fracture of the femoral neck. Patients and Methods. From the Norwegian Hip Fracture Register (NHFR), 20 532 primary cemented bipolar hemiarthroplasties, which were undertaken in patients aged > 70 years with a femoral neck fracture between 2005 and 2016, were included. Polished tapered stems (n = 12 065) (Exeter and CPT), straight stems (n = 5545) (Charnley, Charnley Modular, and Spectron EF), and anatomical stems (n = 2922) (Lubinus SP2) were included. The survival of the implant with any reoperation as the endpoint was calculated using the Kaplan–Meier method and hazard ratios (HRs), and the different indications for reoperation were calculated using Cox regression analysis. Results. The one-year survival was 96.0% (95% confidence interval (CI) 95.6 to 96.4) for the Exeter stem, 97.0% (95% CI 96.4 to 97.6) for the Lubinus SP2 stem, 97.6% (95% CI 97.0 to 98.2) for the Charnley stem, 98.1% (95% CI 97.3 to 98.9) for the Spectron EF stem, and 96.4% (95% CI 95.6 to 97.2) for the Charnley Modular stem, respectively. The hazard ratio for reoperation after one year was lower for Lubinus SP2 (HR 0.77, 95% CI 0.60 to 0.97), Charnley (HR 0.64, 95% CI 0.48 to 0.86), and Spectron EF stems (HR 0.44, 95% CI 0.29 to 0.67) compared with the Exeter stem. Reoperation for periprosthetic fracture occurred almost exclusively after the use of polished tapered stems. Conclusion. We were able to confirm that implant survival after cemented hemiarthroplasty for a hip fracture is high. Differences in rates of reoperation seem to favour anatomical and straight stems compared with polished tapered stems, which had a higher risk of periprosthetic fracture

We prospectively followed 191 consecutive collarless polished tapered (CPT) femoral stems, implanted in 175 patients who had a mean age at operation of 64.5 years (21 to 85). At a mean follow-up of 15.9 years (14 to 17.5), 86 patients (95 hips) were still alive. The fate of all original stems is known. The 16-year survivorship with re-operation for any reason was 80.7% (95% confidence interval 72 to 89.4). There was no loss to follow-up, with clinical data available on all 95 hips and radiological assessment performed on 90 hips (95%). At latest follow-up, the mean Harris hip score was 78 (28 to 100) and the mean Oxford hip score was 36 (15 to 48). Stems subsided within the cement mantle, with a mean subsidence of 2.1 mm (0.4 to 19.2). Among the original cohort, only one stem (0.5%) has been revised due to aseptic loosening. In total seven stems were revised for any cause, of which four revisions were required for infection following revision of the acetabular component. A total of 21 patients (11%) required some sort of revision procedure; all except three of these resulted from failure of the acetabular component. Cemented acetabular components had a significantly lower revision burden (three hips, 2.7%) than Harris Galante uncemented components (17 hips, 21.8%) (p < 0.001). The CPT stem continues to provide excellent radiological and clinical outcomes at 15 years following implantation. Its results are consistent with other polished tapered stem designs

Aims

This aim of this study was to assess the reliability and validity of the Unified Classification System (UCS) for postoperative periprosthetic femoral fractures (PFFs) around cemented polished taper-slip (PTS) stems.

This was a safety study where the hypothesis was that the newer-design CPCS femoral stem would demonstrate similar early clinical results and micromovement to the well-established Exeter stem. Both are collarless, tapered, polished cemented stems, the only difference being a slight lateral to medial taper with the CPCS stem. A total of 34 patients were enrolled in a single-blinded randomised controlled trial in which 17 patients received a dedicated radiostereometric CPCS stem and 17 a radiostereometric Exeter stem. No difference was found in any of the outcome measures pre-operatively or post-operatively between groups. At two years, the mean subsidence for the CPCS stem was nearly half that seen for the Exeter stem (0.77 mm (−0.943 to 1.77) and 1.25 mm (0.719 to 1.625), respectively; p = 0.032). In contrast, the mean internal rotation of the CPCS stem was approximately twice that of the Exeter (1.61° (−1.07° to 4.33°) and 0.59° (0.97° to 1.64°), respectively; p = 0.048). Other migration patterns were not significantly different between the stems. The subtle differences in designs may explain the different patterns of migration. Comparable migration with the Exeter stem suggests that the CPCS design will perform well in the long term

The Unified Classification System (UCS), or Vancouver system, is a validated and widely used classification system to guide the management of periprosthetic femoral fractures. It suggests that well-fixed stems (type B1) can be treated with fixation but that loose stems (types B2 and B3) should be revised. Determining whether a stem is loose can be difficult and some authors have questioned how to apply this classification system to polished taper slip stems which are, by definition, loose within their cement mantle. Recent evidence has challenged the common perception that revision surgery is preferable to fixation surgery for UCS-B periprosthetic fractures around cemented polished taper slip stems. Indications for fixation include an anatomically reducible fracture and cement mantle, a well-fixed femoral bone-cement interface, and a well-functioning acetabular component. However, not all type B fractures can or should be managed with fixation due to the risk of early failure. This annotation details specific fracture patterns that should not be managed with fixation alone.

Cite this article: Bone Joint J 2023;105-B(5):481–486.

Aims

The aims of this study were to evaluate the incidence of reoperation (all cause and specifically for periprosthetic femoral fracture (PFF)) and mortality, and associated risk factors, following a hemiarthroplasty incorporating a cemented collarless polished taper slip stem (PTS) for management of an intracapsular hip fracture.

Background

Approximately half of all hip fractures are displaced intracapsular fractures. The standard treatment for these fractures is either hemiarthroplasty or total hip arthroplasty. The recent National Institute for Health and Care Excellence (NICE) guidance on hip fracture management recommends the use of ‘proven’ cemented stem arthroplasty with an Orthopaedic Device Evaluation Panel (ODEP) rating of at least 3B (97% survival at three years). The Thompsons prosthesis is currently lacking an ODEP rating despite over 50 years of clinical use, likely due to the paucity of implant survival data. Nationally, adherence to these guidelines is varied as there is debate as to which prosthesis optimises patient outcomes.

Femoral impaction bone allografting has been developed as a means of restoring bone stock in revision total hip replacement. We report the results of 75 consecutive patients (75 hips) with a mean age of 68 years (35 to 87) who underwent impaction grafting using the Exeter collarless, polished, tapered femoral stem between 1992 and 1998.

The mean follow-up period was 10.5 years (6.3 to 14.1). The median pre-operative bone defect score was 3 (interquartile range (IQR) 2 to 3) using the Endo-Klinik classification.

The median subsidence at one year post-operatively was 2 mm (IQR 1 to 3). At the final review the median Harris hip score was 80.6 (IQR 67.6 to 88.9) and the median subsidence 2 mm (IQR 1 to 4). Incorporation of the allograft into trabecular bone and secondary remodelling were noted radiologically at the final follow-up in 87% (393 of 452 zones) and 40% (181 of 452 zones), respectively.

Subsidence of the Exeter stem correlated with the pre-operative Endo-Klinik bone loss score (p = 0.037). The degree of subsidence at one year had a strong association with long-term subsidence (p < 0.001). There was a significant correlation between previous revision surgery and a poor Harris Hip score (p = 0.028), and those who had undergone previous revision surgery for infection had a higher risk of complications (p = 0.048). Survivorship at 10.5 years with any further femoral operation as the end-point was 92% (95% confidence interval 82 to 97).

Aims. Highly polished stems with force-closed design have shown satisfactory clinical results despite being related to relatively high early migration. It has been suggested that the minimal thickness of cement mantles surrounding the femoral stem should be 2 mm to 4 mm to avoid aseptic loosening. The line-to-line cementing technique of the femoral stem, designed to achieve stem press-fit, challenges this opinion. We compared the migration of a highly polished stem with force-closed design by standard and line-to-line cementing to investigate whether differences in early migration of the stems occur in a clinical study. Methods. In this single-blind, randomized controlled, clinical radiostereometric analysis (RSA) study, the migration pattern of the cemented Corail hip stem was compared between line-to-line and standard cementing in 48 arthroplasties. The primary outcome measure was femoral stem migration in terms of rotation and translation around and along with the X-, Y-, and Z- axes measured using model-based RSA at three, 12, and 24 months. A linear mixed-effects model was used for statistical analysis. Results. Results from mixed model analyses revealed a lower mean retroversion for line-to-line (0.72° (95% confidence interval (CI) 0.38° to 1.07°; p < 0.001), but no significant differences in subsidence between the techniques (-0.15 mm (95% CI -0.53 to 0.227; p = 0.429) at 24 months. Radiolucent lines measuring < 2 mm wide were found in three and five arthroplasties cemented by the standard and line-to-line method, respectively. Conclusion. The cemented Corail stem with a force-closed design seems to settle earlier and better with the line-to-line cementing method, although for subsidence the difference was not significant. However, the lower rate of migration into retroversion may reduce the wear and cement deformation, contributing to good long-term fixation and implant survival. Cite this article: Bone Joint J 2022;104-B(1):19–26

Aims. The aim of this study was to compare the design of the generic OptiStem XTR femoral stem with the established Exeter femoral stem. Materials and Methods. We obtained five boxed, as manufactured, implants of both designs at random (ten in total). Two examiners were blinded to the implant design and independently measured the mass, volume, trunnion surface topography, trunnion roughness, trunnion cone angle, Caput-Collum-Diaphyseal (CCD) angle, femoral offset, stem length, neck length, and the width and roughness of the polished stem shaft using peer-reviewed methods. We then compared the stems using these parameters. Results. We found that the OptiStems were lighter (p < 0.001), had a rougher trunnion surface (p <  0.001) with a greater spacing and depth of the machined threads (p < 0.001), had greater trunnion cone angles (p = 0.007), and a smaller radius at the top of the trunnion (p = 0.007). There was no difference in stem volume (p = 0.643), CCD angle (p = 0.788), offset (p = 0.993), neck length (p = 0.344), stem length (p = 0.808), shaft width (p = 0.058 to 0.720) or roughness of the polished surface (p = 0.536). Conclusion. This preliminary investigation found that whilst there were similarities between the two designs, the generic OptiStem is different to the branded Exeter design. Cite this article: Bone Joint J 2017;99-B:310–16

We have compared prospectively the incidence of loosening of 20 femoral stems with a matt surface with that of 20 polished stems of an otherwise identical tapered, non-modular design of Exeter hip replacement. The stems were inserted using the same technique at operation and radiographs showed no difference in the adequacy of the cement mantle or of fixation. All the patients were reviewed regularly and none was lost to follow-up. After a minimum follow-up of nine years, four matt but no polished stems had been revised for aseptic loosening. Polished stems subsided slightly within the cement mantle early, but did not loosen

Objective. Cement thickness of at least 2 mm is generally associated with more favorable results for the femoral component in cemented hip arthroplasty. However, French-designed stems have shown favorable outcomes even with thin cement mantle. The biomechanical behaviors of a French stem, Charnley-Marcel-Kerboull (CMK) and cement were researched in this study. Methods. Six polished CMK stems were implanted into a composite femur, and one million times dynamic loading tests were performed. Stem subsidence and the compressive force at the bone-cement interface were measured. Tantalum ball (ball) migration in the cement was analyzed by micro CT. Results. The cement thickness of 95 % of the proximal and middle region was less than 2.5 mm. A small amount of stem subsidence was observed even with collar contact. The greatest compressive force was observed at the proximal medial region and significant positive correlation was observed between stem subsidence and compressive force. 9 of 11 balls in the medial region moved to the horizontal direction more than that of the perpendicular direction. The amount of ball movement distance in the perpendicular direction was 59 to 83% of the stem subsidence, which was thought to be slip in the cement of the stem. No cement defect and no cement breakage were seen. Conclusion. Thin cement in CMK stems produced effective hoop stress without excessive stem and cement subsidence. Polished CMK stem may work like force-closed fixation in short-term experiment. Cite this article: Y. Numata, A. Kaneuji, L. Kerboull, E. Takahashi, T. Ichiseki, K. Fukui, J. Tsujioka, N. Kawahara. Biomechanical behaviour of a French femoral component with thin cement mantle: The ‘French paradox’ may not be a paradox after all. Bone Joint Res 2018;7:485–493. DOI: 10.1302/2046-3758.77.BJR-2017-0288.R2

Aims. Debate continues about whether it is better to use a cemented or uncemented hemiarthroplasty to treat a displaced intracapsular fracture of the hip. The aim of this study was to attempt to resolve this issue for contemporary prostheses. Methods. A total of 400 patients with a displaced intracapsular fracture of the hip were randomized to receive either a cemented polished tapered stem hemiarthroplasty or an uncemented Furlong hydroxyapatite-coated hemiarthroplasty. Follow-up was conducted by a nurse blinded to the implant at set intervals for up to one year from surgery. Results. A total of 115 patients died in the year after surgery. There was a tendency towards a slightly higher mortality in those treated with the uncemented prosthesis after one year (64 vs 51; p = 0.18). For the survivors, there was no significant difference in pain score at any of the time intervals. Patients treated using the cemented hemiarthroplasty recovered mobility better than those treated with the uncemented hemiarthroplasty (mean decrease in mobility score at one year: 1.7 vs 1.1, SD 1.9; p = 0.008). There was a tendency to more periprosthetic fractures in the uncemented group (five vs two cases; p = 0.45), but overall the need for further surgery was similar in both groups (nine vs seven cases). There were four perioperative deaths in the cemented group. Conclusion. These results indicate that a contemporary cemented hemiarthroplasty gives better results than an uncemented hemiarthroplasty for patients with a displaced intracapsular fracture of the hip. When the condition of the patient permits, a cemented hemiarthroplasty should be used. Cite this article: Bone Joint J. 2020;102-B(1):11–16

Aims. Femoral impaction bone grafting was first developed in 1987 using morselised cancellous bone graft impacted into the femoral canal in combination with a cemented, tapered, polished stem. We describe the evolution of this technique and instrumentation since that time. . Patients and Methods. Between 1987 and 2005, 705 revision total hip arthroplasties (56 bilateral) were performed with femoral impaction grafting using a cemented femoral stem. All surviving patients were prospectively followed for a mean of 14.7 years (9.8 to 28.3) with no loss to follow-up. By the time of the final review, 404 patients had died. Results. There were 76 further revisions (10.8%) involving the stem; seven for aseptic loosening, 23 for periprosthetic fracture, 24 for infection, one for malposition, one for fracture of the stem and 19 cement-in-cement exchanges of the stem during acetabular revision. The 20-year survival rate for the entire series was 98.8% (95% confidence interval (CI) 97.8 to 99.8) with aseptic loosening as the endpoint, and 87.7% (95% CI 82.8 to 92.6) for revision for any reason. Survival improved with the evolution of the technique, although this was not statistically significant due to the overall low rate of further revision. Conclusion. This is the largest series of revision total hip arthroplasties with femoral impaction grafting, and the results support the continued use of this technique. Cite this article: Bone Joint J 2016;98-B:1611–19

Aims. The Exeter V40 cemented polished tapered stem system has demonstrated excellent long-term outcomes. This paper presents a systematic review of the existing literature and reports on a large case series comparing implant fractures between the Exeter V40 series; 125 mm and conventional length stem systems. Methods. A systematic literature search was performed adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. In parallel, we performed a retrospective single centre study of Exeter V40 femoral stem prosthetic fractures between April 2003 and June 2020. Results. There are 25 reported cases of such prosthetic fractures confined to small case series and case reports within the literature. We report an additional 19 cases to the literature (mean age 66.3 years (SD 11.7); 12 (63%) females; BMI 32.9 kg/m. 2. (SD 5.9)). The mean time from index procedure to fracture was 7.8 years (SD 3.6; 2.5 to 16.3). Exeter V40 stem fracture incidence was 0.15% and 1.21% for primary and revision arthroplasty, respectively. Incidence was significantly higher in revision arthroplasty (p < 0.001) and 125 mm length stems compared to ≥ 150 mm length stems (1.25% vs 0.13%, respectively; p < 0.001). When comparing different stem length cohorts, 125 mm short-stems were associated with stem-body fractures (92% vs 29%; p = 0.0095), earlier time to fracture (6.2 years vs 11.0 years; p = 0.0018), younger patient age at time of fracture (62.7 years vs 72.6 years; p = 0.037), and female sex (75% vs 43%; p = 0.326). Conclusion. This complication remains rare, although we report a significantly higher incidence at up to 17 years follow-up than in the literature. Short 125 mm length Exeter V40 stems undoubtedly have a role in restoring anatomy and biomechanics in smaller femoral geometries, although the surgeon has to appreciate the higher risk of stem fracture and the associated predisposing factors which may necessitate particular attention to surgical technique and planning. Cite this article: Bone Jt Open 2021;2(6):443–456

Aims

The aim of this study was to report the three-year follow-up for a series of 400 patients with a displaced intracapsular fracture of the hip, who were randomized to be treated with either a cemented polished tapered hemiarthroplasty or an uncemented hydroxyapatite-coated hemiarthroplasty.

Aims

Periprosthetic hip fractures (PPFs) after total hip arthroplasty are difficult to treat. Therefore, it is important to identify modifiable risk factors such as stem selection to reduce the occurrence of PPFs. This study aimed to clarify differences in fracture torque, surface strain, and fracture type analysis between three different types of cemented stems.

We studied the effect of the surface finish of the stem on the transfer of load in the proximal femur in a sheep model of cemented hip arthroplasty. Strain-gauge analysis and corresponding finite-element (FE) analysis were performed to assess the effect of friction and creep at the cement-stem interface. No difference was seen between the matt and polished stems. FE analysis showed that the effects of cement creep and friction at the stem-cement interface on femoral strain were small compared with the effect of inserting a cemented stem

Aims

The Exeter short stem was designed for patients with Dorr type A femora and short-term results are promising. The aim of this study was to evaluate the minimum five-year stem migration pattern of Exeter short stems in comparison with Exeter standard stems.

We describe the results of 81 consecutive revision total hip replacements with impaction grafting in 79 patients using a collared polished chrome–cobalt stem, customised in length according to the extent of distal bone loss. Our hypothesis was that the features of this stem would reduce the rate of femoral fracture and subsidence of the stem. The mean follow-up was 12 years (8 to 15). No intra-operative fracture or significant subsidence occurred. Only one patient suffered a post-operative diaphyseal fracture, which was associated with a fall. All but one femur showed incorporation of the graft. No revision for aseptic loosening was recorded. The rate of survival of the femoral component at 12 years, using further femoral revision as the endpoint, was 100% (95% confidence interval (CI) 95.9 to 100), and at nine years using re-operation for any reason as the endpoint, was 94.6% (95% CI 92.0 to 97.2). These results suggest that a customised cemented polished stem individually adapted to the extent of bone loss and with a collar may reduce subsidence and the rate of fracture while maintaining the durability of the fixation

We have prospectively studied the wear of enhanced ultra-high molecular-weight polyethylene (Hylamer) in combination with a zirconia femoral head of 22.225 mm diameter on a cemented, triple-tapered, collarless, polished stem, the C Stem. The 71 patients who underwent total hip arthroplasty had a mean follow-up of six years (3 to 8). No patient died or was lost to follow-up. The clinical results were excellent with 96% of patients satisfied. There were no revisions. Two cups were considered to be loose radiologically. One was avulsed from the cement in a skiing accident, with a periprosthetic fracture of the femur, but has remained stable for more than seven years. One femur shows radiological appearances which are compatible with a healing infection. One femoral component is at risk of loosening. The mean rate of penetration of the cup was 0.22 mm/year (0.06 to 0.55). Our results appear to be within the guidelines set by the National Institute of Clinical Excellence. We have discontinued the use of Hylamer despite excellent clinical results and no revisions to date because the high initial rates of penetration did not settle to the expected low levels within the anticipated time

It has been suggested that the endurance of cemented femoral reconstructions in total hip arthroplasty is affected by the creep of acrylic cement, but it is not known to what extent cement creeps under loading conditions in vivo, or how this affects load transfer. We have simulated the long-term creep properties of acrylic cement in finite-element models of femoral stem constructs and analysed their effects. We investigated whether subsidence rates measured in vivo could be explained by creep of acrylic cement, and if polished, unbonded, stems accommodated creep better than bonded stems. Our findings showed that polished prostheses subsided only about 50 μm as a result of cement creep. The long-term prosthetic subsidence rates caused by creep of acrylic cement are therefore very small and do not explain the excessive migration rates which have sometimes been reported. Cement creep did, however, relax cement stresses and create a more favourable stress distribution at the interfaces. These trends were found around both the bonded and unbonded stems. Our results did not confirm that polished, unbonded, stems accommodated creep better than bonded stems in terms of cement and interface stress patterns

The October 2024 Trauma Roundup³⁶⁰ looks at: Early versus delayed weightbearing following operatively treated ankle fracture (WAX): a non-inferiority, multicentre, randomized controlled trial; The effect of early weightbearing and later weightbearing rehabilitation interventions on outcomes after ankle fracture surgery; Is intramedullary nailing of femoral diaphyseal fractures in the lateral decubitus position as safe and effective as on a traction table?; Periprosthetic fractures of the hip: Back to the Future, Groundhog Day, and horses for courses; Two big bones, one big decision: when to fix bilateral femur fractures; Comparison of ankle fracture fixation using intramedullary fibular nailing versus plate fixation; Unclassified acetabular fractures: do they really exist?

Polished taper-slip (PTS) cemented stems have an excellent clinical track record and are the most common stem type used in primary total hip arthroplasty (THA) in the UK. Due to low rates of aseptic loosening, they have largely replaced more traditional composite beam (CB) cemented stems. However, there is now emerging evidence from multiple joint registries that PTS stems are associated with higher rates of postoperative periprosthetic femoral fracture (PFF) compared to their CB stem counterparts. The risk of both intraoperative and postoperative PFF remains greater with uncemented stems compared to either of these cemented stem subtypes. PFF continues to be a devastating complication following primary THA and is associated with high complication and mortality rates. Recent efforts have focused on identifying implant-related risk factors for PFF in order to guide preventative strategies, and therefore the purpose of this article is to present the current evidence on the effect of cemented femoral stem design on the risk of PFF.

Cite this article: Bone Joint J 2024;106-B(1):11–15.

The April 2023 Hip & Pelvis Roundup³⁶⁰ looks at: Do technical errors determine outcomes of operatively managed femoral neck fractures in younger adults?; Single-stage or two-stage revision for hip prosthetic joint infection (INFORM); Fixation better than revision in type B periprosthetic fractures of taper slip stems; Can you maximize femoral head size at the expense of liner thickness?; Plasma D-dimer for periprosthetic joint infection?; How important is in vivo oxidation?; Total hip arthroplasty for HIV patients with osteonecrosis.

The February 2024 Hip & Pelvis Roundup³⁶⁰ looks at: Trial of vancomycin and cefazolin as surgical prophylaxis in arthroplasty; Is preoperative posterior femoral neck tilt a risk factor for fixation failure? Cemented versus uncemented hemiarthroplasty for displaced intracapsular fractures of the hip; Periprosthetic fractures in larger hydroxyapatite-coated stems: are collared stems a better alternative for total hip arthroplasty?; Postoperative periprosthetic fracture following hip arthroplasty with a polished taper slip versus composite beam stem; Is oral tranexamic acid as good as intravenous?; Stem design and the risk of early periprosthetic femur fractures following THA in elderly patients; Does powered femoral broaching compromise patient safety in total hip arthroplasty?

Aims

Several different designs of hemiarthroplasty are used to treat intracapsular fractures of the proximal femur, with large variations in costs. No clinical benefit of modular over monoblock designs has been reported in the literature. Long-term data are lacking. The aim of this study was to report the ten-year implant survival of commonly used designs of hemiarthroplasty.

The August 2023 Hip & Pelvis Roundup³⁶⁰ looks at: Using machine learning to predict venous thromboembolism and major bleeding events following total joint arthroplasty; Antibiotic length in revision total hip arthroplasty; Preoperative colonization and worse outcomes; Short stem cemented total hip arthroplasty; What are the outcomes of one- versus two-stage revisions in the UK?; To cement or not to cement? The best approach in hemiarthroplasty; Similar re-revisions in cemented and cementless femoral revisions for periprosthetic femoral fractures in total hip arthroplasty; Are hip precautions still needed?

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.

Aims

The aim of this study was to compare open reduction and internal fixation (ORIF) with revision surgery for the surgical management of Unified Classification System (UCS) type B periprosthetic femoral fractures around cemented polished taper-slip femoral components following primary total hip arthroplasty (THA).

Aims

Deep surgical site infection (SSI) remains an unsolved problem after hip fracture. Debridement, antibiotic, and implant retention (DAIR) has become a mainstream treatment in elective periprosthetic joint infection; however, evidence for DAIR after infected hip hemiarthroplaty is limited.

Aims

Femoral cement-in-cement revision is a well described technique to reduce morbidity and complications in hip revision surgery. Traditional techniques for septic revision of hip arthroplasty necessitate removal of all bone cement from the femur. In our two centres, we have been using a cement-in-cement technique, leaving the distal femoral bone cement in selected patients for septic hip revision surgery, both for single and the first of two-stage revision procedures. A prerequisite for adoption of this technique is that the surgeon considers the cement mantle to be intimately fixed to bone without an intervening membrane between cement and host bone. We aim to report our experience for this technique.

Aims

There is a paucity of long-term studies analyzing risk factors for failure after single-stage revision for periprosthetic joint infection (PJI) following total hip arthroplasty (THA). We report the mid- to long-term septic and non-septic failure rate of single-stage revision for PJI after THA.

Aims

The aim of this study was to determine whether fixation, as opposed to revision arthroplasty, can be safely used to treat reducible Vancouver B type fractures in association with a cemented collarless polished tapered femoral stem (the Exeter).

We report the clinical and radiographic outcomes of 208 consecutive femoral revision arthroplasties performed in 202 patients (119 women, 83 men) between March 1991 and December 2007 using the X-change Femoral Revision System, fresh-frozen morcellised allograft and a cemented polished Exeter stem. All patients were followed prospectively. The mean age of the patients at revision was 65 years (30 to 86). At final review in December 2013 a total of 130 patients with 135 reconstructions (64.9%) were alive and had a non re-revised femoral component after a mean follow-up of 10.6 years (4.7 to 20.9). One patient was lost to follow-up at six years, and their data were included up to this point. Re-operation for any reason was performed in 33 hips (15.9%), in 13 of which the femoral component was re-revised (6.3%). The mean pre-operative Harris hip score was 52 (19 to 95) (n = 73) and improved to 80 (22 to 100) (n = 161) by the last follow-up. Kaplan–Meier survival with femoral re-revision for any reason as the endpoint was 94.9% (95% confidence intervals (CI) 90.2 to 97.4) at ten years; with femoral re-revision for aseptic loosening as the endpoint it was 99.4% (95% CI 95.7 to 99.9); with femoral re-operation for any reason as the endpoint it was 84.5% (95% CI 78.3 to 89.1); and with subsidence ≥ 5 mm it was 87.3% (95% CI 80.5 to 91.8). Femoral revision with the use of impaction allograft bone grafting and a cemented polished stem results in a satisfying survival rate at a mean of ten years’ follow-up. Cite this article: Bone Joint J 2015; 97-B:771–9

Aims

We aimed to report the mid- to long-term rates of septic and aseptic failure after two-stage revision surgery for periprosthetic joint infection (PJI) following total hip arthroplasty (THA).

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Hip arthroplasty does not always restore normal anatomy. This is due to inaccurate surgery or lack of stem sizes. We evaluated the aptitude of four total hip arthroplasty systems to restore an anatomical and medialized hip rotation centre.

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This study evaluates risk factors influencing fracture characteristics for postoperative periprosthetic femoral fractures (PFFs) around cemented stems in total hip arthroplasty.

We have evaluated the in vivo migration patterns of 164 primary consecutive Charnley-Kerboull total hip replacements which were undertaken in 155 patients. The femoral preparation included removal of diaphyseal cancellous bone to obtain primary rotational stability of the stem before line-to-line cementing. We used the Ein Bild Roentgen Analyse femoral component method to assess the subsidence of the femoral component. At a mean of 17.3 years (15.1 to 18.3) 73 patients were still alive and had not been revised, eight had been revised, 66 had died and eight had been lost to follow-up. The mean subsidence of the entire series was 0.63 mm (0.0 to 1.94). When using a 1.5 mm threshold, only four stems were considered to have subsided. Our study showed that, in most cases, a highly polished double-tapered stem cemented line-to-line does not subside at least up to 18 years after implantation

Aims

Periprosthetic fractures (PPFs) around cemented taper-slip femoral prostheses often result in a femoral component that is loose at the prosthesis-cement interface, but where the cement-bone interface remains well-fixed and bone stock is good. We aim to understand how best to classify and manage these fractures by using a modification of the Vancouver classification.

Aims

The Exeter V40 cemented femoral stem was first introduced in 2000. The largest single-centre analysis of this implant to date was published in 2018 by Westerman et al. Excellent results were reported at a minimum of ten years for the first 540 cases performed at the designer centre in the Exeter NHS Trust, with stem survivorship of 96.8%. The aim of this current study is to report long-term outcomes and survivorship for the Exeter V40 stem in a non-designer centre.

We have tested the axial and torsional stability of femoral components after revision arthroplasty in a cadaver model, using impacted morsellised cancellous graft and cement. Each one of six matched pairs of fresh frozen human femora had either a primary or a revision prosthesis cemented in place. For the ‘revision’ experiments, all cancellous bone was removed from the proximal femur which was then over-reamed to create a smooth-walled cortical shell. An MTS servohydraulic test frame was used to apply axial and torsional loads to each specimen through the prosthetic femoral heads with the femur submerged in isotonic saline solution at 37°C. The mean subsidence was 0.27 ± 0.17 mm for the primary and 0.52 ± 0.30 mm for the revision groups. The difference was statistically significant (p < 0.025), but the mean subsidence was < 1 mm in both groups. The mean maximum torque before failure was 42.9 ± 26.9 N-m for the primary and 34.8± 20.7 N-m for the revision groups. This difference was not statistically significant (p > 0.015). Based on our results we suggest that revision of the femoral component using morsellised cancellous graft followed by cementing with a collarless prosthesis with a polished tapered stem restores the integrity of the proximal femur and provides immediate stability of the implant