Aims. Heterotopic ossification (HO) is a common complication after elbow trauma and can cause severe upper limb disability. Although multiple prognostic factors have been reported to be associated with the development of post-traumatic HO, no model has yet been able to combine these predictors more succinctly to convey prognostic information and medical measures to patients. Therefore, this study aimed to identify prognostic factors leading to the formation of HO after surgery for elbow trauma, and to establish and validate a nomogram to predict the probability of HO formation in such particular injuries. Methods. This multicentre case-control study comprised 200 patients with post-traumatic elbow HO and 229 patients who had elbow trauma but without HO formation between July 2019 and December 2020. Features possibly associated with HO formation were obtained. The least absolute shrinkage and selection operator regression model was used to optimize feature selection. Multivariable logistic regression analysis was applied to build the new nomogram: the Shanghai post-Traumatic Elbow Heterotopic Ossification Prediction model (STEHOP). STEHOP was validated by concordance index (C-index) and calibration plot. Internal validation was conducted using bootstrapping validation. Results. Male sex, obesity, open wound, dislocations, late definitive surgical treatment, and lack of use of non-steroidal anti-inflammatory drugs were identified as adverse predictors and incorporated to construct the STEHOP model. It displayed good discrimination with a C-index of 0.80 (95% confidence interval 0.75 to 0.84). A high C-index value of 0.77 could still be reached in the internal validation. The calibration plot showed good agreement between nomogram prediction and observed outcomes. Conclusion. The newly developed STEHOP model is a valid and convenient instrument to predict HO formation after surgery for elbow trauma. It could assist clinicians in counselling patients regarding treatment expectations and therapeutic choices. Cite this article: Bone Joint J 2022;104-B(8):963–971

Aims. In patients with a failed radial head arthroplasty (RHA), simple removal of the implant is an option. However, there is little information in the literature about the outcome of this procedure. The aim of this study was to review the mid-term clinical and radiological results, and the rate of complications and removal of the implant, in patients whose initial RHA was undertaken acutely for trauma involving the elbow. Methods. A total of 11 patients in whom removal of a RHA without reimplantation was undertaken as a revision procedure were reviewed at a mean follow-up of 8.4 years (6 to 11). The range of motion (ROM) and stability of the elbow were recorded. Pain was assessed using a visual analogue scale (VAS). The functional outcome was assessed using the Mayo Elbow Performance Score (MEPS), the Oxford Elbow Score (OES), and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH). Radiological examination included the assessment of heterotopic ossification (HO), implant loosening, capitellar erosion, overlengthening, and osteoarthritis. Complications and the rate of further surgery were also recorded. Results. The indications for removal of the implant were stiffness in five patients, aseptic loosening in five, and pain attributed to the RHA in three. The mean time interval between RHA for trauma to removal was ten months (7 to 21). Preoperatively, three patients had overlengthening of the implant, three had capitellar erosion, six had HO, and four had radiological evidence of loosening. At the final follow-up, the mean the flexion-extension arc improved significantly by 38.2° (95% CI 20 to 59; p = 0.002) and the mean arc of prono-supination improved significantly by 20° (95% CI 0 to 72.5; p = 0.035). The mean pain VAS score improved significantly by 3.5 (95% CI 2 to 5.5; p = 0.004). The mean MEPS improved significantly by 27.5 (95% CI 17.5 to 42.5; p = 0.002). The mean OES improved significantly by 9 (95% CI 2.5 to 14; p = 0.012), and the mean DASH score improved significantly by 23.5 (95% CI 7.5 to 31.6; p = 0.012). Ten patients (91%) had HO and osteoarthritis. Two patients underwent further surgery due to stiffness and pain, respectively. Conclusion. Simple removal of the implant at revision surgery following a failed RHA introduced following trauma provides satisfactory mid-term results with an acceptable risk of complications. Osteoarthritis, instability, and radioulnar impingement were not problems in this series. Cite this article: Bone Joint J 2024;106-B(11):1327–1332

Aims. Whether to perform hybrid surgery (HS) in contrast to anterior cervical discectomy and fusion (ACDF) when treating patients with multilevel cervical disc degeneration remains a controversial subject. To resolve this we have undertaken a meta-analysis comparing the outcomes from HS with ACDF in this condition. Methods. Seven databases were searched for studies of HS and ACDF from inception of the study to 1 September 2019. Both random-effects and fixed-effects models were used to evaluate the overall effect of the C2-C7 range of motion (ROM), ROM of superior/inferior adjacent levels, adjacent segment degeneration (ASD), heterotopic ossification (HO), complications, neck disability index (NDI) score, visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Odom’s criteria, blood loss, and operating and hospitalization time. To obtain more credible results contour-enhanced funnel plots, Egger’s and Begg’s tests, meta-regression, and sensitivity analyses were performed. Results. In total, 17 studies involving 861 patients were included in the analysis. HS was found to be superior to ACDF in maintaining C2-C7 ROM and ROM of superior/inferior adjacent levels, but HS did not reduce the incidence of associated level ASD. Also, HS did not cause a higher rate of HO than ACDF. The frequency of complications was similar between the two techniques. HS failed to achieve more favourable outcomes than ACDF using the NDI, VAS, JOA, and Odom’s scores. HS did not show any more advantages in operating or hospitalization time but did show reduction in blood loss. Conclusion. Although HS maintained cervical kinetics, it failed to reduce the incidence of ASD. This finding differs from previous reports. Moreover, patients did not show more benefits from HS with respect to symptom improvement, prevention of complications, and clinical outcomes. Cite this article: Bone Joint J 2020;102-B(8):981–996

Aims. Heterotopic ossification (HO) occurs after arthroplasty, especially total hip arthroplasty. In this study we describe the incidence, evolution, morphology and clinical consequences of HO following reverse shoulder arthroplasty. Patients and Methods. This is a single-centre retrospective study of 132 consecutive patients who received a Delta III or Delta Xtend reverse total shoulder arthroplasty between 2006 and 2013 for the treatment of cuff tear arthropathy. There were 96 women and 36 men. Their mean age at the time of surgery was 69 years (49 to 89) and the mean follow-up was 36 months (12 to 84). The incidence, evolution, morphology and clinical consequences of HO using the Constant-Murley score (CS) were analysed. A modified Brooker classification of HO of the hip was used. Results. HO was seen in 39 patients (29.5%). A total of 31 of these patients (81.6%) began to develop HO by three months post-operatively. According to the Hamada classification, 11 patients had grade 1a, eight had grade 1b, six had grade 1c and 14 had grade 2 HO. The HO evolved over a mean of 8.3 months (3 to 21). Patients with HO had a lower mean CS at three (p = 0.017), six (p < 0.001) and 12 months (p < 0.001) post-operatively. HO was not associated with notching (p = 0.675). Conclusion. HO after reverse shoulder arthroplasty is a non-progressive condition without long-term clinical consequences. Only grade 2 HO is clinically relevant with a negative effect on the function of the shoulder during its development. Cite this article: Bone Joint J 2016;98-B:1215–21

Aims. Heterotopic ossification (HO) is a potentially devastating complication of the surgical treatment of a proximal humeral fracture. The literature on the rate and risk factors for the development of HO under these circumstances is lacking. The aim of this study was to determine the incidence and risk factors for the development of HO in these patients. Methods. A retrospective analysis of 170 patients who underwent operative treatment for a proximal humeral fracture between 2005 and 2016, in a single institution, was undertaken. The mean follow-up was 18.2 months (1.5 to 140). The presence of HO was identified on follow-up radiographs. Results. The incidence of HO was 15% (n = 26). Our multivariate model revealed that male sex (odds ratio (OR) 3.57, 95% confidence interval (CI) 1.30 to 9.80 compared to female) and dislocation as the initial injury (OR 5.01, 95% CI 1.31 to 19.22) were significantly associated with the formation of HO (p < 0.05) while no significant associations were seen for the age of the patient, the characteristics of the injury, or the type of operative treatment. Conclusion. This retrospective radiological study is the first to investigate the association between the method of surgical treatment for a proximal humeral fracture and the formation of HO postoperatively. We found that male sex and dislocation as the initial injury were risk factors for HO formation, whereas the method of surgical treatment, the age of the patient, and the pattern of the fracture were not predictive of HO formation. While additional studies are needed, these findings can help to identify those at an increased risk for HO formation under these circumstances. Cite this article: Bone Joint J 2020;102-B(4):539–544

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 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

Aim. The primary aim of this retrospective study was to identify the incidence of heterotopic ossification (HO) following elective and trauma elbow arthroplasty. The secondary aim was to determine clinical outcomes with respect to the formation of heterotopic ossification. Patients and Methods. A total of 55 total elbow arthroplasties (TEAs) (52 patients) performed between June 2007 and December 2015 were eligible for inclusion in the study (29 TEAs for primary elective arthroplasty and 26 TEAs for trauma). At review, 15 patients (17 total elbow arthroplasties) had died from unrelated causes. There were 14 men and 38 women with a mean age of 70 years (42 to 90). The median clinical follow-up was 3.6 years (1.2 to 6) and the median radiological follow-up was 3.1 years (0.5 to 7.5). Results. The overall incidence of HO was 84% (46/55). This was higher in the trauma group (96%, 25/26) compared with the elective arthroplasty group (72%, 21/29) (p = 0.027, Fisher’s exact test). Patients in the trauma group had HO of higher Brooker class. The presence of HO did not significantly affect elbow range of movement within the trauma or elective groups (elective arthroplasty, Mann–Whitney U test, p = 0.070; trauma arthroplasty, p = 0.370, Mann–Whitney U test). Conclusion. HO after total elbow arthroplasty is seen more commonly than previously reported. We have reported a significantly higher rate of HO in TEAs performed for trauma than those performed electively. Cite this article: Bone Joint J 2018;100-B:767–71

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

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

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

We retrospectively reviewed 89 consecutive patients (45 men and 44 women) with a mean age at the time of injury of 58 years (18 to 97) who had undergone external fixation after sustaining a unilateral fracture of the distal humerus. Our objectives were to determine the incidence of heterotopic ossification (HO); identify risk factors associated with the development of HO; and characterise the location, severity and resultant functional impairment attributable to the presence of HO. . HO was identified in 37 elbows (42%), mostly around the humerus and along the course of the medial collateral ligament. HO was hazy immature in five elbows (13.5%), mature discrete in 20 (54%), extensive mature in 10 (27%), and complete bone bridges were present in two elbows (5.5%). Mild functional impairment occurred in eight patients, moderate in 27 and severe in two. HO was associated with less extension (p = 0.032) and less overall flexion-to-extension movement (p = 0.022); the flexion-to-extension arc was < 100º in 21 elbows (57%) with HO compared with 18 elbows (35%) without HO (p = 0.03). HO was removed surgically in seven elbows. . The development of HO was significantly associated with sustaining a head injury (p = 0.015), delayed internal fixation (p = 0.027), the method of fracture fixation (p = 0.039) and the use of bone graft or substitute (p = 0.02).HO continues to be a substantial complication after internal fixation for distal humerus fractures. Cite this article: Bone Joint J 2014;96-B:1681–7

Heterotopic ossification (HO) of the hip after injury to the central nervous system can lead to joint ankylosis. Surgery is usually delayed to avoid recurrence, even if the functional status is affected. We report a consecutive series of patients with HO of the hip after injury to the central nervous system who required surgery in a single, specialised tertiary referral unit. As was usual practice, they all underwent CT to determine the location of the HO and to evaluate the density of the femoral head and articular surface. The outcome of surgery was correlated with the pre-, peri- and post-operative findings. In all, 183 hips (143 patients) were included of which 70 were ankylosed. A total of 25 peri-operative fractures of the femoral neck occurred, all of which arose in patients with ankylosed hips and were associated with intra-articular lesions in 18 and severe osteopenia of the femoral head in seven. All the intra-articular lesions were predicted by CT and strongly associated with post-operative complications. The loss of the range of movement before ankylosis is a more important factor than the maturity of the HO in deciding the timing of surgery. Early surgical intervention minimises the development of intra-articular pathology, osteoporosis and the resultant complications without increasing the risk of recurrence of HO

Indomethacin is commonly administered for the prophylaxis of heterotopic ossification (HO) after the surgical treatment of acetabular fractures. Non-steroidal anti-inflammatory drugs such as indomethacin, have been associated with delayed healing of fractures and mechanically weaker callus. Our aim was to determine if patients with an acetabular fracture, who received indomethacin for prophylaxis against HO, were at risk of delayed healing or nonunion of any associated fractures of long bones. We reviewed 282 patients who had had open reduction and internal fixation of an acetabular fracture. Patients at risk of HO were randomised to receive either radiation therapy (XRT) or indomethacin. Of these patients, 112 had sustained at least one concomitant fracture of a long bone; 36 needed no prophylaxis, 38 received focal radiation and 38 received indomethacin. Fifteen patients developed 16 nonunions. When comparing patients who received indomethacin with those who did not, a significant difference was noted in the rate of nonunion (26% v 7%; p = 0.004). Patients with concurrent fractures of the acetabulum and long bones who receive indomethacin have a significantly greater risk of nonunion of the fractures of the long bones when compared with those who receive XRT or no prophylaxis

We have studied prospectively the effect of indomethacin on the development of heterotopic ossification (HO) after the internal fixation of acetabular fractures. After operation 107 patients randomly received either a six-week course of indomethacin or no treatment against HO. Plain radiographs of 101 patients at a mean of 7.9 months after surgery showed HO in 47.4% of the 57 patients who received indomethacin and in 56.8% of the 44 who did not. This difference was not statistically significant. Heterotopic ossification of Brooker class II or more was seen in four patients (7%) with prophylaxis and in one without (p = 0.51). Measurements of the volume of HO on 3-D CT reconstructions showed a median value of 1.5 cm. 3. in patients with indomethacin and 4.0 cm. 3. in those without (p = 0.28). When only the 57 patients in whom the operation was carried out through either a Kocher-Langenbeck or an extended iliofemoral approach were included the indomethacin group showed a median volume of 1.7 cm. 3. compared with 3.6 cm. 3. On plain radiographs Brooker class II or above was seen in 9.4% of the patients receiving indomethacin and in 4.8% of those who did not. Indomethacin was therefore not effective in preventing ectopic bone formation after surgery for acetabular fractures. There was a significant association of male gender with volume of HO using a non-parametric analysis of variance

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

We report a prospective, randomised, blinded clinical comparison of the use of indomethacin or radiation therapy for the prevention of heterotopic ossification (HO) in 75 adults who had open reduction and internal fixation of acetabular fractures through either a Kocher-Langenbeck, a combined ilioinguinal and Kocher-Langenbeck, or an extended iliofemoral approach. Indomethacin, 25 mg, was given three times daily for six weeks. Radiation with 800 cGy was delivered within three days of operation. Plain radiographs were reviewed and given Brooker classification scores by three independent observers who were unaware of the method of prophylaxis. One patient died from unrelated causes and two were lost to follow-up, leaving 72, 33 in the radiation group and 39 in the indomethacin group, available for evaluation at a mean of 12 months (6 to 48). There was no significant difference in the two groups in terms of age, gender, injury severity score, estimated blood loss, delay to surgery, head injury, presence of femoral head dislocation, or operating time, and no complications due to either method of treatment. The final extent of HO was already present by six weeks in all patients who were followed up. Three patients in the radiation group and five who received indomethacin developed HO of Brooker grade III. Two patients in the indomethacin group developed Brooker IV changes; both had failed to receive proper doses of the drug. Cochran-Armitage analysis showed no significant difference between the two treatment groups as regards the formation of HO. Indomethacin and single-dose radiation therapy are both safe and effective for the prevention of HO after operation for acetabular fractures. Radiation therapy is, however, approximately 200 times more expensive than indomethacin therapy at our institution and has other risks

Aims

The aim of this study was to develop and internally validate a prognostic nomogram to predict the probability of gaining a functional range of motion (ROM ≥ 120°) after open arthrolysis of the elbow in patients with post-traumatic stiffness of the elbow.

Aims

The aim of this study was to evaluate the outcome of complex radial head fractures at mid-term follow-up, and determine whether open reduction and internal fixation (ORIF) or radial head arthroplasty (RHA) should be recommended for surgical treatment.

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.