Aims. We aimed to assess the influence of ethnicity on the incidence of heterotopic ossification (HO) after total hip arthroplasty (THA). . Patients and Methods. We studied the six-month post-operative anteroposterior radiographs of 1449 consecutive primary THAs (1324 patients) and retrospectively graded them for the presence of HO, using the Brooker Classification. . Results. Based on multivariate analysis, African-American ethnicity was an independent risk factor for HO formation following THA with an adjusted odds ratio (OR) of 2.6 (95% confidence interval (CI) 1.3 to 5.2, p = 0.007) for severe HO and 1.9 (95% CI 1.3 to 2.7, p < 0.001) for any grade of HO. . Conclusion. Given the increased risk of HO formation, particularly high grade HO, and the potentially poorer outcomes associated with HO, it is important to consider using prophylaxis against HO in patients of African-American ethnicity undergoing THA. Take home message: African Americans are at an increased risk for developing heterotopic ossification and thus may benefit from HO prophylaxis. . Cite this article: Bone Joint J 2016;98-B:761–6

Aims. The aim of this study was to assess the efficacy of non-selective and selective non-steroidal anti-inflammatory drugs (NSAIDs) in preventing heterotopic ossification (HO) after total hip arthroplasty (THA). Methods. A thorough and systematic literature search was conducted and 29 studies were found that met inclusion criteria. Data were extracted and statistical analysis was carried out generating forest plots. Results. Non-selective NSAIDs showed a significant decrease in the odds for forming HO after THA (odds ratio (OR) -1.35, confidence interval (CI) -1.83 to -0.86) when compared with placebo. Selective NSAIDs also showed a significant decrease in the odds for forming HO after THA when compared with placebo (OR -1.58, CI -2.41 to -0.75). When comparing non-selective NSAIDs with selective NSAIDs, there was no significant change in the odds for forming HO after THA (OR 0.22, CI -0.36 to 0.79). Conclusion. Our meta-analyses of all available data suggest that both non-selective and selective NSAIDs are effective HO prophylaxis and can be used routinely after THA for pain control as well as prevention of HO. Indomethacin may serve as the benchmark among non-selective NSAIDs and celecoxib among selective NSAIDs. There was no difference in the incidence of HO between non-selective and selective NSAIDs, allowing physicians to choose either based on the clinical scenario and patient-specific factors. Cite this article: Bone Joint J 2018;100-B:915–22

We examined whether a selective cyclooxygenase-2 (COX-2) inhibitor (celecoxib) was as effective as a non-selective inhibitor (ibuprofen) for the prevention of heterotopic ossification following total hip replacement. A total of 250 patients were randomised to receive celecoxib (200 mg b/d) or ibuprofen (400 mg t.d.s) for ten days after surgery. Anteroposterior radiographs of the pelvis were examined for heterotopic ossification three months after surgery. Of the 250 patients, 240 were available for assessment. Heterotopic ossification was more common in the ibuprofen group (none 40.7% (50), Brooker class I 46.3% (57), classes II and III 13.0% (16)) than in the celecoxib group (none 59.0% (69), Brooker class I 35.9% (42), classes II and III 5.1% (6), p = 0.002). Celecoxib was more effective than ibuprofen in preventing heterotopic bone formation after total hip replacement

We have carried out a prospective, randomised study of prophylaxis for heterotopic ossification (HO) comparing indomethacin for 7 and 14 days, acetylsalicylic acid, and fractional (4 × 3 Gy) or single exposure of 5 or 7 Gy irradiation after operation. We initially had 723 patients (733 hip replacements), but after withdrawals there were 685 hips of which 18.4% developed HO; 14% were grade I, 2.9% grade II and 1.5% grade III of the Brooker classification. We compared the results between these groups with those of a matched control series and found that indomethacin, 2 × 50 mg for 7 and 14 days, and postoperative irradiation of 4 × 3 Gy or 1 × 7 Gy, significantly reduced the development of HO compared with the control group. Patients in the acetylsalicylic acid group and those with a single irradiation of 5 Gy after operation developed significantly more ossification than those in the indomethacin and other irradiation groups. We suggest the use of 2 × 50 mg of indomethacin with mucoprotection for seven days as prophylaxis against HO after total hip replacement for all patients. A single irradiation of 7 Gy is recommended for patients who have developed HO after previous operations or to whom administration of indomethacin is contraindicated

In this paper we propose a new classification of neurogenic peri-articular heterotopic ossification (HO) of the hip based on three-dimensional (3D) CT, with the aim of improving pre-operative planning for its excision. . A total of 55 patients (73 hips) with clinically significant HO after either traumatic brain or spinal cord injury were assessed by 3D-CT scanning, and the results compared with the intra-operative findings. At operation, the gross pathological anatomy of the HO as identified by 3D-CT imaging was confirmed as affecting the peri-articular hip muscles to a greater or lesser extent. We identified seven patterns of involvement: four basic (anterior, medial, posterior and lateral) and three mixed (anteromedial, posterolateral and circumferential). Excellent intra- and inter-observer agreement, with kappa values > 0.8, confirmed the reproducibility of the classification system. We describe the different surgical approaches used to excise the HO which were guided by the 3D-CT findings. Resection was always successful. . 3D-CT imaging, complemented in some cases by angiography, allows the surgeon to define the 3D anatomy of the HO accurately and to plan its surgical excision with precision. Cite this article: Bone Joint J 2015; 97-B:899–904

In patients with severe quadriplegic cerebral palsy and painful hip dislocation proximal femoral resection arthroplasty can reduce pain, but the risk of heterotopic ossification is significant. We present a surgical technique of autologous capping of the femoral stump in order to reduce this risk, using the resected femoral head as the graft. A retrospective study of 31 patients (43 hips) who had undergone proximal femoral resection arthroplasty with (29 hips) and without autologous capping (14 hips) was undertaken. Heterotopic ossification was less frequent in patients with autologous capping, and a more predictable pattern of bony overgrowth was found. For a selected group of non-ambulatory patients with long-standing painful dislocation of the hip, we recommend femoral resection arthroplasty over more complicated reconstructive operations. The risk of heterotopic ossification, which is a major disadvantage of this operation, is reduced by autologous capping

Aims. This study reports mid-term outcomes after periacetabular osteotomy (PAO) exclusively in a borderline hip dysplasia (BHD) population to provide a contrast to published outcomes for arthroscopic surgery of the hip in BHD. Methods. We identified 42 hips in 40 patients treated between January 2009 and January 2016 with BHD defined as a lateral centre-edge angle (LCEA) of ≥ 18° but < 25°. A minimum five-year follow-up was available. Patient-reported outcomes (PROMs) including Tegner score, subjective hip value (SHV), modified Harris Hip Score (mHHS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were assessed. The following morphological parameters were evaluated: LCEA, acetabular index (AI), α angle, Tönnis staging, acetabular retroversion, femoral version, femoroepiphyseal acetabular roof index (FEAR), iliocapsularis to rectus femoris ratio (IC/RF), and labral and ligamentum teres (LT) pathology. Results. The mean follow-up was 96 months (67 to 139). The SHV, mHHS, WOMAC, and Tegner scores significantly improved (p < 0.001) at last follow-up. According to SHV and mHHS, there were three hips (7%) with poor results (SHV < 70), three (7%) with a fair score (70 to 79), eight (19%) with good results (80 to 89), and 28 (67%) who scored excellent (> 90) at the last follow-up. There were 11 subsequent operations: nine implant removals due to local irritation, one resection of postoperative heterotopic ossification, and one hip arthroscopy for intra-articular adhesions. No hips were converted to total hip arthroplasty at last follow-up. The presence of preoperative labral lesions or LT lesions did not influence any PROMs at last follow-up. From the three hips that had poor PROMs, two have developed severe osteoarthritis (> Tönnis II), presumably due to surgical overcorrection (postoperative AI < -10°). Conclusion. PAO is reliable in treating BHD with favourable mid-term outcomes. Concomitant LT and labral lesions did not negatively influence outcomes in our cohort. Technical accuracy with avoidance of overcorrection is essential in achieving successful outcomes. Cite this article: Bone Joint J 2023;105-B(7):735–742

Eighteen hip fusions were converted to total hip replacements. A constrained acetabular liner was used in three hips. Mean follow up was five years (two to 15). Two (11%) hips failed, requiring revision surgery and two patients (11%) had injury to the peroneal nerve. Heterotopic ossification developed in seven (39%) hips, in one case resulting in joint ankylosis. No hips dislocated. . Conversion of hip fusion to hip replacement carries an increased risk of heterotopic ossification and neurological injury. We advise prophylaxis against heterotropic ossification. When there is concern about hip stability we suggest that the use of a constrained acetabular liner is considered. Despite the potential for complications, this procedure had a high success rate and was effective in restoring hip function

Aims. Head-taper corrosion is a cause of failure in total hip arthroplasty (THA). Recent reports have described an increasing number of V40 taper failures with adverse local tissue reaction (ALTR). However, the real incidence of V40 taper damage and its cause remain unknown. The aim of this study was to evaluate the long-term incidence of ALTR in a consecutive series of THAs using a V40 taper and identify potentially related factors. Methods. Between January 2006 and June 2007, a total of 121 patients underwent THA using either an uncemented (Accolade I, made of Ti. 12. Mo. 6. Zr. 2. Fe; Stryker, USA) or a cemented (ABG II, made of cobalt-chrome-molybdenum (CoCrMo); Stryker) femoral component, both with a V40 taper (Stryker). Uncemented acetabular components (Trident; Stryker) with crosslinked polyethylene liners and CoCr femoral heads of 36 mm diameter were used in all patients. At a mean folllow-up of 10.8 years (SD 1.1), 94 patients (79%) were eligible for follow-up (six patients had already undergone a revision, 15 had died, and six were lost to follow-up). A total of 85 THAs in 80 patients (mean age 61 years (24 to 75); 47 (56%) were female) underwent clinical and radiological evaluation, including the measurement of whole blood levels of cobalt and chrome. Metal artifact reduction sequence MRI scans of the hip were performed in 71 patients. Results. A total of 20 ALTRs were identified on MRI, with an incidence of 26%. Patients with ALTR had significantly higher median Co levels compared with those without ALTR (2.96 μg/l (interquartile range (IQR) 1.35 to 4.98) vs 1.44 μg/l (IQR 0.79 to 2.5); p = 0.019). Radiological evidence of osteolysis was also significantly associated with ALTR (p = 0.014). Median Cr levels were not significantly higher in those with ALTR compared with those without one (0.97 μg/l (IQR 0.72 to 1.9) v 0.67 μg/l (IQR 0.5 to 1.19; p = 0.080). BMI, sex, age, type of femoral component, head length, the inclination of the acetabular component, and heterotopic ossification formation showed no significant relationship with ALTR. Conclusion. Due to the high incidence of local ALTR in our cohort after more than ten years postoperatively, we recommend regular follow-up investigation even in asymptomatic patients with V40 taper and metal heads. As cobalt levels correlate with ALTR occurrence, routine metal ion screening and consecutive MRI investigation upon elevation could be discussed. Cite this article: Bone Joint J 2022;104-B(7):852–858

The painful subluxed or dislocated hip in adults with cerebral palsy presents a challenging problem. Prosthetic dislocation and heterotopic ossification are particular concerns. We present the first reported series of 19 such patients (20 hips) treated with hip resurfacing and proximal femoral osteotomy. The pre-operative Gross Motor Function Classification System (GMFCS) was level V in 13 (68%) patients, level IV in three (16%), level III in one (5%) and level II in two (11%). The mean age at operation was 37 years (13 to 57). The mean follow-up was 8.0 years (2.7 to 11.6), and 16 of the 18 (89%) contactable patients or their carers felt that the surgery had been worthwhile. Pain was relieved in 16 of the 18 surviving hips (89%) at the last follow-up, and the GMFCS level had improved in seven (37%) patients. There were two (10%) early dislocations; three hips (15%) required revision of femoral fixation, and two hips (10%) required revision, for late traumatic fracture of the femoral neck and extra-articular impingement, respectively. Hence there were significant surgical complications in a total of seven hips (35%). No hips required revision for instability, and there were no cases of heterotopic ossification. We recommend hip resurfacing with proximal femoral osteotomy for the treatment of the painful subluxed or dislocated hip in patients with cerebral palsy

Aims. Improvements in functional results and long-term survival are variable following conversion of hip fusion to total hip arthroplasty (THA) and complications are high. The aim of the study was to analyze the clinical and functional results in patients who underwent conversion of hip fusion to THA using a consistent technique and uncemented implants. Methods. A total of 39 hip fusion conversions to THA were undertaken in 38 patients by a single surgeon employing a consistent surgical technique and uncemented implants. Parameters assessed included Harris Hip Score (HHS) for function, range of motion (ROM), leg length discrepancy (LLD), satisfaction, and use of walking aid. Radiographs were reviewed for loosening, subsidence, and heterotopic ossification (HO). Postoperative complications and implant survival were assessed. Results. At mean 12.2 years (2 to 24) follow-up, HHS improved from mean 34.2 (20.8 to 60.5) to 75 (53.6 to 94.0; p < 0.001). Mean postoperative ROM was flexion 77° (50° to 95°), abduction 30° (10° to 40°), adduction 20° (5° to 25°), internal rotation 18° (2° to 30°), and external rotation 17° (5° to 30°). LLD improved from mean -3.36 cm (0 to 8) to postoperative mean -1.14 cm (0 to 4; p < 0.001). Postoperatively, 26 patients (68.4%) required the use of a walking aid. Complications included one (2.5%) dislocation, two (5.1%) partial sciatic nerve injuries, one (2.5%) deep periprosthetic joint infection, two instances of (5.1%) acetabular component aseptic loosening, two (5.1%) periprosthetic fractures, and ten instances of HO (40%), of which three (7.7%) were functionally limiting and required excision. Kaplan-Meier Survival was 97.1% (95% confidence interval (CI) 91.4% to 100%) at ten years and 88.2% (95% CI 70.96 to 100) at 15 years with implant revision for aseptic loosening as endpoint and 81.7% (95% CI 70.9% to 98.0%) at ten years and 74.2% (95% CI 55.6 to 92.8) at 15 years follow-up with implant revision for all cause failure as endpoint. Conclusion. The use of an optimal and consistent surgical technique and cementless implants can result in significant functional improvement, low complication rates, long-term implant survival, and high patient satisfaction following conversion of hip fusion to THA. The possibility of requiring a walking aid should be discussed with the patient before surgery. Cite this article: Bone Joint J 2021;103-B(7 Supple B):129–134

Aims. The classical longitudinal incision used for the direct anterior approach (DAA) to the hip does not follow the tension lines of the skin and can lead to impaired wound healing and poor cosmesis. The purpose of this retrospective study was to determine the satisfaction with the scar, and functional and radiographic outcomes comparing the classic longitudinal incision with a modified skin crease ‘bikini’ when the DAA is used for total hip arthroplasty (THA). Patients and Methods. A total of 964 patients (51% female; 59% longitudinal, 41% ‘bikini’) completed a follow-up questionnaire between two and four years postoperatively, including the Oxford Hip Score (OHS), the University of North Carolina ‘4P’ scar scale (UNC4P) and two items for assessing the aesthetic appearance of the scar and symptoms of numbness. The positioning of the components, rates of heterotopic ossification (HO) and rates of revision were assessed. Results. The mean OHS was similar in both groups (p = 0.41). The mean UNC4P total score was slightly better (p = 0.01) and the proportion of patients who were very satisfied with the cosmetic aspects of the scar was higher in the ‘bikini’ group (p < 0.001). The proportion of patients reporting numbness in the scar was higher in the longitudinal group (14.5% vs 7.5%, respectively, p < 0.001). The abduction angle of the acetabular component, the position of the stem and rates of HO did not differ between the groups. There were no differences in the revision rates of both groups, being 2.3% in the longitudinal and 1.5% in the ‘bikini’ group (p = 0.911). Conclusion. We found that a short oblique ‘bikini’ skin crease incision is safe when used for the DAA at THA, without compromising the positioning of the components or increasing the rate of lateral femoral cutaneous nerve dysaesthesia. Although it leads to a superior scar satisfaction, as it is less extensile, it should be used after having gained experience with the classic longitudinal incision. Cite this article: Bone Joint J 2018;100-B:853–61

This preliminary study evaluates a combination of bone morphogenetic protein (BMP)-7 and non-vascularised autologous fibular grafting (AFG) for the treatment of osteonecrosis of the femoral head. BMP-7/AFG combination was applied in seven pre-collapse femoral heads (five Steinberg stage II, two stage III) in six patients. Pre- and post-operative evaluation included clinical (Harris hip score (HHS), visual analogue scale (VAS) for pain) and radiological assessment (radiographs, quantitative CT) at a mean follow-up of 4 years (2 to 5.5). A marked improvement of function (mean HHS increase of 49.2) and decrease of pain level (mean VAS decrease of 5) as well as retention of the sphericity of the femoral head was noted in five hips at the latest follow-up, while signs of consolidation were apparent from the third post-operative month. One patient (two hips) required bilateral total hip replacement at one year post-operatively. In the series as a whole, quantitative-CT evaluation revealed similar densities between affected and normal bone. Heterotopic ossification was observed in four hips, without compromise of the clinical outcome. In this limited series AFG/BMP-7 combination proved a safe and effective method for the treatment of femoral head osteonecrosis, leading to early consolidation of the AFG and preventing collapse in five of seven hips, while the operative time and post-operative rehabilitation period were much shorter compared with free vascularised fibular grafts. Cite this article: Bone Joint J 2014;96-B:31–5

A prospective, multi-centre study was carried out on 1421 total hip replacements between January 1999 and July 2007 to examine if obesity has an effect on clinical outcomes. The patients were categorised into three groups: non-obese (body mass index (BMI) < 30 kg/m. 2. ), obese (BMI 30 to 40 kg/m. 2. ) and morbidly obese (BMI > 40 kg/m. 2. ). The primary outcome measure was the change in Oxford hip score at five years. Secondary outcome measures included dislocation and revision rates, increased haemorrhage, deep infection, deep-vein thrombosis and pulmonary embolism, mean operating time and length of hospital stay. Radiological analysis assessing heterotopic ossification, femoral osteolysis and femoral stem positioning was performed. Data were incomplete for 362 hips (25.5%). There was no difference in the change in the Oxford hip score, complication rates or radiological changes at five years between the groups. The morbidly obese group was significantly younger and required a significantly longer operating time. Obese and morbidly obese patients have as much to gain from total hip replacement as non-obese patients

Between 1981 and 1986 two groups of patients received either Charnley low-friction arthroplasties or the Wrightington Frusto-Conical hip replacement with otherwise identical management before and after operation. There were 260 consecutive replacements in 215 patients in the first group and 260 consecutive procedures in 211 patients in the second. Both components of each design were cemented and featured a 22.25 mm femoral head, but the geometry of the stems differed. Of the patients lost to follow-up, 16 (18 hips) were in the Wrightington series and 24 (36 hips) in the Charnley series, and of those who have died 20 (23 hips) were Wrightington and 14 (16 hips) were Charnley. All surviving patients have been followed up clinically and radiologically or until revision was necessary. The mean length of follow-up for original surviving components in both series was 140 months (120 to 180). Pain, function and movement were measured by the grading system of Merle D’Aubign′e and Postel and showed a marked improvement in both groups. There was little or no pain in 98% of patients in the Wrightington series and 96% in the Charnley series, while 93% and 85%, respectively, were entirely painfree. Trochanteric osteotomy was used in 292 cases overall, with a complication rate of 13% due to wire breakage, trochanteric bursitis or trochanteric detachment, requiring a further operation in 5.8% (17 hips). Heterotopic ossification was seen in 40% of cases in which trochanteric osteotomy had been performed (117 hips) but only 3% (10 hips) had clinically significant changes. After the direct lateral approach heterotopic ossification was seen in 24% (42 hips) with only 2% in class 3 or 4 (4 hips). Femoral osteolysis was more common in the Charnley series, occurring in 7.6% of cases (17 hips) as opposed to 2.1% (5 hips) in the Wrightington series. Ten acetabular and seven femoral components have been revised in the Wrightington series and 16 acetabular and 11 femoral implants in the Charnley series. Survivorship based on revision for aseptic loosening using the Kaplan-Meier technique showed survival of the femoral implant at 5, 10 and 15 years of 100%, 99% and 98%, respectively in the Wrightington and 100%, 99% and 87% in the Charnley series. The survival of the acetabular component at 10, 12 and 15 years respectively, was 100%, 99% and 95% for the Wrightington, and 99%, 98% and 84% for the Charnley. The survival of both the acetabular and femoral components of the Wrightington system at a mean of 11.7 years was better than that of the Charnley system, with a lower incidence of radiological loosening of unrevised components

We report the clinical and radiological outcome of 86 revisions of cemented hip arthroplasties using JRI-Furlong hydroxyapatite-ceramic-coated acetabular and femoral components. The acetabular component was revised in 62 hips and the femoral component in all hips. The mean follow-up was 12.6 years and no patient was lost to follow-up. The mean age of the patients was 71.2 years. The mean Harris hip and Oxford scores were 82 (59 to 96) and 23.4 (14 to 40), respectively. The mean Charnley modification of the Merle d’Aubigné and Postel score was 5 (3 to 6) for pain, 4.9 (3 to 6) for movement and 4.4 (3 to 6) for mobility. Migration of the acetabular component was seen in two hips and the mean acetabular inclination was 42.6°. The mean linear polyethylene wear was 0.05 mm/year. The mean subsidence of the femoral component was 1.9 mm and stress shielding was seen in 23 (28%) with bony ingrowth in 76 (94%). Heterotopic ossification was seen in 12 hips (15%). There were three re-revisions, two for deep sepsis and one for recurrent dislocation and there were no re-revisions for aseptic loosening. The mean EuroQol EQ-5D description scores and health thermometer scores were 0.69 (0.51 to 0.89) and 79 (54 to 95), respectively. With an end-point of definite or probable loosening, the probability of survival at 12 years was 93.9% and 95.6% for the acetabular and femoral components, respectively. Overall survival at 12 years, with removal or further revision of either component for any reason as the end-point, was 92.3%. Our study supports the continued use of this arthroplasty and documents the durability of hydroxyapatite-ceramic-coated components

Between 1980 and 2000, 63 support rings were used in the management of acetabular deficiency in a series of 60 patients, with a mean follow-up of 8.75 years (2 months to 23.8 years). There was a minimum five-year follow-up for successful reconstructions. The indication for revision surgery was aseptic loosening in 30 cases and infection in 33. All cases were Paprosky III defects; IIIA in 33 patients (52.4%) and IIIB in 30 (47.6%), including four with pelvic dissociation. A total of 26 patients (43.3%) have died since surgery, and 34 (56.7%) remain under clinical review. With acetabular revision for infection or aseptic loosening as the definition of failure, we report success in 53 (84%) of the reconstructions. A total of 12 failures (19%) required further surgery, four (6.3%) for aseptic loosening of the acetabular construct, six (9.5%) for recurrent infection and two (3.2%) for recurrent dislocation requiring captive components. Complications, seen in 11 patients (18.3%), included six femoral or sciatic neuropraxias which all resolved, one grade III heterotopic ossification, one on-table acetabular revision for instability, and three early post-operative dislocations managed by manipulation under anaesthesia, with no further instability. We recommend support rings and morcellised bone graft for significant acetabular bone deficiency that cannot be reconstructed using mesh

We describe the results of 76 total arthroplasties of the hip for stage-III or stage-IV avascular necrosis of the femoral head. Harris Galante Porous cups were used in 63 patients between 1986 and 1994 and followed prospectively. We reviewed 70 hips with a follow-up of more than five years (mean 7.6). At the latest review the mean Harris Hip Score had improved from a preoperative value of 29 ± 14.7 to 94 ± 6.8. Radiologically, there was no evidence of acetabular migration. The rate of revision for the femoral component was 8.6%, three being undertaken for loosening and three to allow downsizing of the femoral head. The rate of revision for the acetabular component was 7.1% (five cups). At the time of revision none of the cups was clinically loose, and only required the liner to be changed. The rate of complications was low with no case of deep infection or dislocation, but nine of the 76 hips (11.8%) showed grade-III heterotopic ossification. Previous studies of patients undergoing cemented total hip arthroplasty for the treatment of advanced avascular necrosis have indicated a high incidence of loosening of the acetabular component. Our findings show good medium-term results using the Harris Galante Porous cup for acetabular reconstruction, together with a variety of cemented femoral components, for the treatment of this difficult problem

Aims

Periacetabular osteotomy (PAO) is widely recognized as a demanding surgical procedure for acetabular reorientation. Reports about the learning curve have primarily focused on complication rates during the initial learning phase. Therefore, our aim was to assess the PAO learning curve from an analytical perspective by determining the number of PAOs required for the duration of surgery to plateau and the accuracy to improve.

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