We investigated 219 revisions of total hip replacement (THR) in 211 patients using a collarless double-taper cemented femoral component. The mean age of the patients was 72 years (30 to 90). The 137 long and 82 standard length stems were analysed separately. The mean follow-up was six years (2 to 18), and no patient was lost to follow-up. Survival of the long stems to re-revision for aseptic loosening at nine years was 98% (95% confidence interval (CI) 94 to 100), and for the standard stems was 93% (95% CI 85 to 100). At five years, one long stem was definitely loose radiologically and one standard stem was probably loose. Pre-operative femoral bone deficiency did not influence the results for the long stems, and corrective femoral osteotomy was avoided, as were significant subsidence, major stress shielding and persistent thigh pain. Because of these reliable results, cemented long collarless double-taper femoral components are recommended for routine revision THR in older patients

The outcome of 219 revision total hip arthroplasties (THAs) in 98 male and 121 female patients, using 137 long length and 82 standard length cemented collarless double-taper femoral stems in 211 patients, with a mean age of 72 years (30 to 90) and mean follow-up of six years (two to 18) have been described previously. We have extended the follow-up to a mean of 13 years (8 to 20) in this cohort of patients in which the pre-operative bone deficiency Paprosky grading was IIIA or worse in 79% and 73% of femurs with long and standard stems, respectively. For the long stem revision group, survival to re-revision for aseptic loosening at 14 years was 97% (95% confidence interval (CI) 91 to 100) and in patients aged > 70 years, survival was 100%. Two patients (two revisions) were lost to follow-up and 86 patients with 88 revisions had died. Worst-case analysis for survival to re-revision for aseptic loosening at 14 years was 95% (95% CI 89 to 100) and 99% (95% CI 96 to 100) for patients aged > 70 years. One additional long stem was classified as loose radiographically but not revised. For the standard stem revision group, survival to re-revision for aseptic loosening at 14 years was 91% (95% CI 83 to 99). No patients were lost to follow-up and 49 patients with 51 hips had died. No additional stems were classified as loose radiographically. Femoral revision using a cemented collarless double-taper stem, particularly with a long length stem, and in patients aged > 70 years, continues to yield excellent results up to 20 years post-operatively, including in hips with considerable femoral metaphyseal bone loss. Cite this article: Bone Joint J 2015;97-B:1038–45

Revision hip surgery is reportedly rising inexorably yet not all units report this phenomenon. The outcome of 1143 consecutive Corin TaperFit primary hip arthroplasties (957 patients) performed between 1995 and 2010 is presented. The implants were cemented under pressurisation and combined the TaperFit stem with Ogee flanged cups. Data was gathered from local arthroplasty database and case note review of revised joints. 13 hips have been revised (1.1%). Cumulative prosthesis survival is 0.99 +/− 0.0. Two femoral stems were revised (0.2%); one at 6 months for sepsis, one at 14 days after dislodgment during reduction of dislocation. No revisions were undertaken for aseptic loosening of the stem or cup, nor for thigh pain. 32 patients (32 hips) ≥15 year follow up, 13 survive today and none have been revised (0%). Of the 471 with ≥10 year follow up, 38 were aged ≤50 at time of surgery and 1/38 has been revised to date (PLAD for dislocation). The strong population stability in this region, supported by independent investigation by Scottish Arthroplasty Project, endorses the accuracy of the data quoted. The low incidence of revision in this cohort, and absence of revision for aseptic loosening (mean follow up 8.03 years +/− SD 3.94; range 18 months to 16yrs 2 months), substantially supports the longevity and use of cemented, double-taper, polished, collarless femoral stems in combination with cemented polyethylene cups in primary hip arthroplasty in all patient age groups

Following the recall of modular neck hip stems in July 2012, research into femoral modularity will intensify over the next few years. This review aims to provide surgeons with an up-to-date summary of the clinically relevant evidence. The development of femoral modularity, and a classification system, is described. The theoretical rationale for modularity is summarised and the clinical outcomes are explored. The review also examines the clinically relevant problems reported following the use of femoral stems with a modular neck.

Joint replacement registries in the United Kingdom and Australia have provided data on the failure rates of modular devices but cannot identify the mechanism of failure. This information is needed to determine whether modular neck femoral stems will be used in the future, and how we should monitor patients who already have them implanted.

Cite this article: Bone Joint J 2013;95-B:1011–21.

Modular necks arrived in North America in the late 1970s. The purpose was to allow ceramic balls to be attached to metal stems. The advantages of modularity were so obvious that it was universally adopted with almost no untoward consequences. A double-taper neck was developed in Italy by the Cremascoli Company and was used extensively with few reports of problems. Recently, problems have been reported not only with double-taper necks, but also with head-neck junction tapers. Something would appear to have changed recently. Some of these changes were shortening of the taper, lengthening of the neck, version angles were increased, and head sizes bigger than 32mm were introduced. Surface finish on some of the tapers was changed and they were ridged. This produces a better fit for a ceramic ball, but facilitates crevice corrosion with a metal ball. The author used the original OTI cemented stem with a double-taper neck between 2002 and 2005. It was a cobalt chrome construct. The Cremascoli was a titanium hip. The OTI used the classic Morse taper with cogs for increased rotational resistance. One hundred forty five stems were inserted. The neck stem taper broke in two cases and dislocated in one. All of these cases had a long neck and long heads and thus produced maximum moment arm. The stem was withdrawn from the market, the taper lengthened and the strength doubled. It was reintroduced in 2007. From 2007 to 2011, the author has done 188 cases, all cemented stems. No taper problems have occurred. The conclusion is that a properly designed double taper neck does not appear to have a downside. The upside is the ability to change neck length and especially version after head insertion. Leg length and hip centering can, therefore, be fine-tuned as never before. The author continues to use this stem enthusiastically for all cemented cases

Introduction. Malalignment of some designs of stem is associated with an increased risk of aseptic loosening and revision. We investigated whether the alignment of the cemented polished, double-taper design adversely affected outcome, in a multicentre prospective study. Methods. A multicentre prospective study of 1189 total hip replacements was undertaken to investigate whether there is an association between surgical outcome and femoral stem alignment. All patients underwent a primary THR with the Exeter femoral stem (Stryker Howmedica Osteonics, Mahwah, NJ) and a variety of acetabular components. The primary outcome measure was the Oxford hip score (OHS) and change in OHS at five years. Secondary outcomes included rate of dislocation and revision. Radiographic evaluation of the femoral component was also undertaken. The long axis of the Exeter femoral component and the long axis of the femoral canal were located, and the angle at the point of intersection measured. The cementing quality was determined as defined by Barrack et al. Radiolucent lines at the cement-stem and cement-bone interface in the five year radiographs were defined using the zones described by Gruen et al. Subsidence was measured as the vertical dimension of the radiolucency craniolateral to the shoulder of the stem in Gruen zone 1 as described by Fowler et al. Cement fractures were recorded. Results. The incidence of varus (>5 ° to the femoral axis), and valgus (>5 °) malignment were 3.7% and 0.8% respectively. Pre-operative demographics and OHS were similar in all groups (p > 0.4). There was no significant difference in OHS or change in OHS between neutral and malaligned groups at 5 years (neutral, mean=40.1, change=23.1; varus, mean=40.1, change=23.7; valgus, mean=42.0, change=26.6; p=0.46 and p=0.45 respectively). There was no significant difference in dislocation rate between the groups (p=0.66). There was also no significant difference in revision rate (p=0.34). There were no statistically significant differences in the incidence of femoral radiolucency, stem subsidence or cement fracture (p > 0.1). Conclusion. This study provides evidence that both varus and valgus implantation does not compromise the short to medium term clinical results of the cemented, polished, double-taper stems. Longer follow-up is required to establish the influence of stem alignment on the incidence of aseptic loosening and revision

Impaction bone grafting with a cemented polished double-taper stem as a technique for revision of the femoral component was introduced in 1987 at our institution. As at January 2000, 540 cases in 487 patients had been performed. All procedures have been studied prospectively and there are no patients lost to follow-up. We present the survivorship and outcome data for these patients. Survivorship at 15 years is 90.6 percent [95 percent confidence interval: 88–93 percent]. Clinical scores show marked and sustained improvement. There have been 45 failures [8.3 percent]. Technical error contributed to 13 of the 24 non-infective complications, but with improved technique plus the addition of long stemmed impaction grafting, there have been no technical errors since 1996. Our results show that revision of the femoral component with impaction bone grafting is a reliable and durable technique with an acceptably low complication rate and with excellent survivorship at 15 years

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.

Impaction bone grafting in conjunction with a cemented polished double-taper stem as a technique for revision of the femoral component was introduced in 1987 at our institution. As at January 2000, 540 cases in 487 patients had been performed by multiple surgeons. All procedures have been studied prospectively, and there are no patients lost to follow-up. We present the survivorship and outcome data for these patients. Survivorship at 15 years is 90.6 percent (95 percent confidence interval:88–93 percent). Four hundred and six hips in 365 patients remain under active follow up, with 122 patients (134 hips) deceased. Averaged clinical scores taken preoperatively, 2 years postoperatively and at latest follow up showed marked and sustained improvement: Charnley Pain 2.7, 5.5, 5.3; Charnley Function 2.1, 4.1, 3.6; Charnley Range of Motion 4.0, 5.4, 5.3; Harris Pain 19, 38, 36; Harris Function 18, 32, 28; and Oxford Hip Score 41, 22, 25. There have been 45 failures (8.3 percent) at an average 7.6 year follow up (range 2.6–15.3 years). Technical error contributed to 13 of the 24 non-infective complications, but with improved technique plus the addition of long stemmed impaction grafting, there have been no technical errors since 1996. Our results show that revision of the femoral component with impaction bone grafting is a reliable and durable technique with an acceptably low complication rate with excellent survivorship at 15 years

Introduction: Impaction bone grafting in conjunction with a cemented polished double-taper stem as a technique for revision of the femoral component was introduced in 1987 at our institution. Methods: As at January 2000, 540 cases in 487 patients had been performed by multiple surgeons. All procedures have been studied prospectively, and there are no patients lost to follow-up. We present the survivorship and outcome data for these patients. Results: Survivorship at 15 years is 90.6 percent (95 percent confidence interval: 88–93 percent). 406 hips in 365 patients remain under active follow up, with 122 patients (134 hips) deceased. Averaged clinical scores taken pre-operatively, 2 years post-operatively, and at latest follow-up show marked and sustained improvement: Charnley Pain 2.7, 5.5, 5.3; Charnley Function 2.1, 4.1, 3.6; Charnley Range of Motion 4.0, 5.4, 5.3; Harris Pain 19, 38, 36; Harris Function 18, 32, 28; and Oxford Hip Score 41, 22, 25. There have been 45 failures (8.3 percent) at an average 7.6 year follow up (range 2.6 – 15.3 years). Technical error contributed to 13 of the 24 non-infective complications, but with improved technique plus the addition of long stemmed impaction grafting, there have been no technical errors since 1996. Conclusion: Our results show that revision of the femoral component with impaction bone grafting is a reliable and durable technique with an acceptably low complication rate with excellent survivorship at 15 years

Introduction and Aims: Impaction bone grafting in conjunction with a cemented polished double-taper stem as a technique for revision of the femoral component was introduced in 1987 at our institution. The aim of this study is to report on the outcome, survivorship, complications and radiological analysis of the first consecutive 540 cases performed in Exeter. Method: As at January 2000, 540 cases in 487 patients had been performed by multiple surgeons. All procedures have been studied prospectively, and there are no patients lost to follow-up. We present the survivorship and outcome data for these patients. Radiological analysis of the pre-operative, immediate post-operative and most recent follow-up radiographs was also performed. This included evaluation of the cement mantle and impacted allograft, stem subsidence within the cement mantle, presence of cortical healing and graft trabeculation on the follow-up radiographs, as well as appearance of radiolucencies and graft resorption. Results: Survivorship at 15 years is 90.6 percent (95 percent confidence interval: 88–93 percent). Four hundred and six hips in 365 patients remain under active follow-up, with 122 patients (134 hips) deceased. Averaged clinical scores taken pre-operatively, two years post-operatively, and at latest follow-up, show marked and sustained improvement: Charnley Pain 2.7, 5.5, 5.3; Charnley Function 2.1, 4.1, 3.6; Charnley Range of Motion 4.0, 5.4, 5.3; Harris Pain 19, 38, 36; Harris Function 18, 32, 28; and Oxford Hip Score 41, 22, 25. There have been 45 failures (8.3 percent) at an average 7.6-year follow-up (range 2.6–15.3 years). Technical error contributed to 13 of the 24 non-infective complications, but with improved technique plus the addition of long stemmed impaction grafting, there have been no technical errors since 1996. Conclusion: Our results show that revision of the femoral component with impaction bone grafting is a reliable and durable technique with an acceptably low complication rate with excellent survivorship at 15 years

Introduction The CPS-Plus stem (Endoplus UK) is a polished double-taper with rectangular cross section maintained throughout for rotational stability. There are 5 stem sizes with proportionate offset, and 5 neck length options. A unique proximal stem centraliser has been shown to increase proximal cement pressurisation during insertion in-vitro, also assists with alignment of the stem and helps create an even cement mantle. RSA analysis has demonstrated linear subsidence in a vertical plane, without posterior head migration and valgus tilt. We report a multi-centre prospective clinical trial. 231 hips in 223 patients have been entered into the study. 151 of these have reached 3 years follow-up. Method Patients were recruited by surgeons working at three centres in the UK, and two in Norway. Merle d Aubigne and Postel, Harris, and Oxford hip scores were recorded pre-operatively and at follow-up (3, 6, 12, 24, 36, 60 months). Radiographic assessment included evaluation of subsidence and the presence of any radiolucencies. Results Hip scores have been very satisfactory. Radiological subsidence is less than 1.5mm in over 95% of cases and only one stem has subsided more than 3mm. There has been one revision for deep sepsis, 7 dislocations and one femoral fracture, but none of these complications were related to the choice of femoral component. There have been no revisions for aseptic loosening. Kaplan Meier survivorship analysis at 36 months for aseptic stem loosening is 0.997 (95% CI 0.977 – 1) and for all-cause revision is 0.981 (95% CI 0.958 – 1). 53 hips had reached 5-year follow-up at 30/9/04. Discussion The tradition of polished tapered stems arose from serendipity and most results have been excellent. The CPS-Plus stem represents an attempt to re-examine the issues relating to rotational stability, subsidence, cement pressurisation and offset. Earlier laboratory studies have now been supplemented by this clinical evaluation, performed in a number of different centres by several surgeons, and the evidence is encouraging. In particular, the RSA subsidence characteristics, cement pressurisation and rotational stability already associated with this implant in-vitro have been supported by excellent survivorship analysis, and the authors believe that increasing familiarity with the concepts raised by this implant will result in clinical benefits in relation to polished taper cemented stem longevity

Introduction: The CPS-Plus stem (Endoplus UK) is a polished double-taper with a rectangular cross section maintained throughout for rotational stability. There are 5 stem sizes with proportionate offset, together with 5 neck length options, and a unique proximal stem centraliser which has been shown to increase proximal cement pressurisation during insertion in-vitro, assists with alignment of the stem and helps create an even cement mantle. RSA analysis has demonstrated linear subsidence in a vertical plane, without the posterior head migration and valgus tilt associated with other designs. Data on the CPS-Plus stem has been obtained from a multi-centre prospective clinical trial. 231 hips in 223 patients have been entered into the study. 151 of these have reached 3 years follow-up. Method: Patients were recruited by surgeons working at three centres in the UK and two in Norway. Merle d Aubigne and Postel, Harris, and Oxford hip scores were recorded pre-operatively and at follow-up (3, 6, 12, 24, 36, 60 months). Radiographic assessment included evaluation of subsidence and the presence of any radiolucencies. Results: Objective and subjective scoring have indicated very satisfactory results. Radiological subsidence is less than 1.5mm in over 95% of cases and only one stem has subsided more than 3mm. There has been one revision for deep sepsis, 7 dislocations and one femoral fracture, but none of these complications were related to the choice of femoral component. There have been no revisions for aseptic loosening. Kaplan Meier survivorship analysis at 36 months for aseptic stem loosening is 0.997 (95% CI 0.977 – 1) and for all-cause revision is 0.981 (95% CI 0.958 – 1). Discussion: The tradition of polished tapered stems arose from serendipity and most results have been excellent. The CPS-Plus stem represents an attempt to re-examine the issues relating to rotational stability, subsidence, cement pressurisation and offset. Earlier laboratory studies have now been supplemented by this clinical evaluation, performed in a number of different centres by several surgeons, and the evidence is encouraging. In particular, the RSA subsidence characteristics, cement pressurisation and rotational stability already associated with this implant in-vitro have been supported by excellent survivorship analysis, and the authors believe that increasing familiarity with the concepts raised by this implant will result in clinical benefits in relation to polished taper cemented stem longevity

Introduction: The CPS-Plus cemented, collarless, polished stem, is a double-taper design with rectangular cross section. An additional proximal stem centraliser ensures optimal alignment of the stem and an even cement mantle and has been shown to increase cement pressurisation during insertion. Guidelines from the National Institute of Clinical Excellence (NICE) recommend comparative clinical evaluation for prostheses without long-term follow-up data and set an initial ‘benchmark’ for performance at 3 years. Data collection for the CPS-Plus stem is on-going as part of a multi-centre prospective clinical trial. 227 patients have been recruited to the trial and 70 of these have reached 3 years follow-up. Method: Patients were recruited to the study by surgeons working at three centres in the UK and two in Norway. Patients were fully evaluated pre-operatively. Operative details, post-operative course and follow-up visits at 3, 6, 12, 24, and 36 months were recorded. Postoperative clinical progress was monitored using recognised scoring systems and radiographic assessment. Results: The mean Harris hip score (0 – 100) improved from 42.7 pre-op to 91.6 at 6 months and 95.8 at 3 years. The mean Merle d’Aubigne and Postel score (0 – 18) improved from 8.55 pre-op to 16.09 at 6 months and 17.08 at 3 years. The mean Oxford hip score (60 – 12) improved from 41.6 pre-op to 14.1 at 3 years. Radiological subsidence at 3 years is less that 1.5mm in 97% of patients and less than 3mm in the remainder. From all 227 implants, there has been one revision for deep infection. There have been no cases of aseptic loosening. Other significant complications include one peri-prosthetic fracture and 4 dislocations, but these were not thought to be related to the design of the implant. Discussion: The early results of the CPS-Plus femoral stem are encouraging and the prosthesis achieves the 3-year benchmark set out in the NICE guidelines, with a zero revision rate in the first 70 patients recruited to the trial. The prosthesis shares many design features with other well-established collarless, polished, tapered stems. The ease of accurate insertion and improved cement pressurisation resulting from its unique design features should ensure excellent medium to long-term outcome. The multi-centre clinical trial will continue to monitor progress

Recent guidance recommends the use of a well-proven cemented femoral stem for hemiarthroplasty in the management of fractures of the femoral neck, and the Exeter Trauma Stem (ETS) has been suggested as an example of such an implant. The design of this stem was based on the well-proven Exeter Total Hip Replacement stem (ETHRS). This study assessed the surface finish of the ETS in comparison with the ETHRS. Two ETSs and two ETHRSs were examined using a profilometer with a precision of 1 nm and compared with an explanted Exeter Matt stem. The mean roughness average (RA) of the ETSs was approximately ten times higher than that of the ETHRSs (0.235 μm (0.095 to 0.452) versus 0.025 μm (0.011 to 0.059); p < 0.001). The historical Exeter Matt stem roughness measured a mean RA of 0.973 μm (0.658 to 1.159). The change of the polished Exeter stem to a matt surface finish in 1976 resulted in a high stem failure rate. We do not yet know whether the surface differences between ETS and ETHRS will be clinically significant. We propose the inclusion of hemiarthroplasty stems in national joint registries.

Cite this article: Bone Joint J 2013;95-B:173–6.

We report the results of 79 patients (81 hips) who underwent impaction grafting at revision hip replacement using the Exeter femoral stem. Their mean age was 64 years (31 to 83). According to the Endoklinik classification, 20 hips had a type 2 bone defect, 40 had type 3, and 21 had type 4. The mean follow-up for unrevised stems was 10.4 years (5 to 17).

There were 12 re-operations due to intra- and post-operative fractures, infection (one hip) and aseptic loosening (one hip). All re-operations affected type 3 (6 hips) and 4 (6 hips) bone defects. The survival rate for re-operation for any cause was 100% for type 2, 81.2% (95% confidence interval (CI) 67.1 to 95.3) for type 3, and 70.8% (95% CI 51.1 to 90.5) for type 4 defects at 14 years. The survival rate with further revision for aseptic loosening as the end point was 98.6% (95% CI 95.8 to 100). The final clinical score was higher for patients with type 2 bone defects than type 4 regarding pain, function and range of movement. Limp was most frequent in the type 4 group (p < 0.001). The mean subsidence of the stem was 2.3 mm (sd 3.7) for hips with a type 2 defect, 4.3 mm (sd 7.2) for type 3 and 9.6 mm (sd 10.8) for type 4 (p = 0.022).

The impacted bone grafting technique has good clinical results in femoral revision. However, major bone defects affect clinical outcome and also result in more operative complications.

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.

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.