Aims. The aim of this study was to evaluate the long-term clinical and radiographic outcomes of the Birmingham Interlocking Pelvic Osteotomy (BIPO). Patients and Methods. In this prospective study, we report the mid- to long-term clinical outcomes of the first 100 consecutive patients (116 hips; 88 in women, 28 in men) undergoing BIPO, reflecting the surgeon’s learning curve. Failure was defined as conversion to hip arthroplasty. The mean age at operation was 31 years (7 to 57). Three patients (three hips) were lost to follow-up. Results. Survivorship was 76% at ten years and 57% at a mean of 17 years. Younger patients (< 20 years) had the best survivorship (20 hips at risk; 90% at 17 years; 95% confidence interval 65 to 97). Post-operative complications occurred after 12 operations (10.4%) over the duration of the study. Increasing patient age and hip arthritis grade were primary determinants of surgical failure. Conclusion. BIPO provides good to excellent survivorship in appropriately selected patients, with a relatively low rate of complications. Our results are comparable with other established methods of periacetabular osteotomy (PAO), such as the Bernese PAO, even during the surgeon’s initial learning curve. Cite this article: Bone Joint J 2017;99-B:724–31

We report the findings of an independent review of 230 consecutive Birmingham hip resurfacings (BHRs) in 213 patients (230 hips) at a mean follow-up of 10.4 years (9.6 to 11.7). A total of 11 hips underwent revision; six patients (six hips) died from unrelated causes; and 13 patients (16 hips) were lost to follow-up. The survival rate for the whole cohort was 94.5% (95% confidence interval (CI) 90.1 to 96.9). The survival rate in women was 89.1% (95% CI 79.2 to 94.4) and in men was 97.5% (95% CI 92.4 to 99.2). Women were 1.4 times more likely to suffer failure than men. For each millimetre increase in component size there was a 19% lower chance of a failure. The mean Oxford hip score was 45.0 (median 47.0, 28 to 48); mean University of California, Los Angeles activity score was 7.4 (median 8.0, 3 to 9); mean patient satisfaction score was 1.4 (median 1.0, 0 to 9). A total of eight hips had lysis in the femoral neck and two hips had acetabular lysis. One hip had progressive radiological changes around the peg of the femoral component. There was no evidence of progressive neck narrowing between five and ten years. Our results confirm that BHR provides good functional outcome and durability for men, at a mean follow-up of ten years. We are now reluctant to undertake hip resurfacing in women with this implant

We present the clinical results and survivorship of consecutive 100 Birmingham Hip Resurfacings in 90 patients at a minimum follow-up of ten years. All procedures were carried out by an independent surgeon who commenced a prospective study in 1998. Patients were assessed clinically using the Western Ontario and McMaster Universities osteoarthritis index, Short-Form 36, Harris hip score and University of California, Los Angeles activity score. Radiological analysis was performed by an independent observer and blood metal ion levels concentrations were measured at ten years post-operatively in 62 patients. The median acetabular component inclination was 46.2° (34° to 59°) and anteversion 11.0° (0° to 30°). The median chromium concentration in the unilateral group was 1.74 (0.41 to 15.23) and for the bilateral group was 2.98 (1.57 to 18.01). The equivalent values for cobalt were 1.67 (0.54 to 20.4) and 1.88 (1.38 to 19.32). In total there were eight failures giving an overall survival at ten years of 92% (95% confidence interval (CI) 86.7 to 97.3). BHR in male patients had an improved survivorship of 94.6% (95% CI 89.4 to 100) compared with females at 84.6% (95% CI 70.7 to 98.5), but this did not reach statistical significance (p = 0.119). Four of the nine BHRs with a bearing diameter of 42 mm failed. The overall results were consistent with data produced from other centres in that the clinical outcome of large male patients was extremely encouraging, whereas the survival of the smaller joints was less satisfactory

Aims. The Birmingham Hip Resurfacing (BHR) arthroplasty has been used as a surgical treatment of coxarthrosis since 1997. We present 20-year results of 234 consecutive BHRs performed in our unit. Methods. Between 1999 and 2001, there were 217 patients: 142 males (65.4%), mean age 52 years (18 to 68) who had 234 implants (17 bilateral). They had patient-reported outcome measures collected, imaging (radiograph and ultrasound), and serum metal ion assessment. Survivorship analysis was performed using Kaplan-Meier estimates. Revision for any cause was considered as an endpoint for the analysis. Results. Mean follow-up was 20.9 years (19.3 to 22.4). Registry data revealed that 19 hips (8.1%) had been revised and 26 patients (12%) had died from causes unrelated to the BHR. Among the remaining 189 hips, 61% were available for clinical follow-up at 20 years (n = 115) and 70% of patients had biochemical follow-up (n = 132). The cumulative implant survival rate at 20 years for male patients was 96.5% (95% confidence interval (CI) 93.5 to 99.6), and for female patients 87% (95% CI 79.7 to 94.9). The difference was statistically significant (p = 0.029). The mean Oxford Hip Score, Hip disability and Osteoarthritis Outcome Score, and Forgotten Joint Score were 45 (29 to 48), 89 (43 to 100), and 84 (19 to 100), respectively. The mean scores for each of the five domains of the EuroQol five-dimension three-level questionnaire were 1.2, 1.0, 1.2, 1.3, and 1.1, and mean overall score 82.6 (50 to 100). Ultrasound showed no pseudotumour. Mean cobalt and chromium levels were 32.1 nmol/l (1 to 374) and 45.5 nmol/l (9 to 408), respectively. Conclusion. This study shows that BHRs provide excellent survivorship and functional outcomes in young male patients. At 20 years, soft-tissue imaging and serum metal ion studies suggest that a metal-on-metal resurfacing implant can be well tolerated in a group of young patients. Cite this article: Bone Joint J 2023;105-B(9):946–952

Aims. The Birmingham Hip Resurfacing (BHR) was introduced in 1997 to address the needs of young active patients using a historically proven large-diameter metal-on-metal (MoM) bearing. A single designer surgeon’s consecutive series of 130 patients (144 hips) was previously reported at five and ten years, reporting three and ten failures, respectively. The aim of this study was to extend the follow-up of this original cohort at 25 years. Methods. The study extends the reporting on the first consecutive 144 resurfacing procedures in 130 patients for all indications. All operations were undertaken between August 1997 and May 1998. The mean age at operation was 52.1 years (SD 9.93; 17 to 76), and included 37 female patients (28.5%). Failure was defined as revision of either component for any reason. Kaplan-Meier survival analysis was performed. Routine follow-up with serum metal ion levels, radiographs, and Oxford Hip Scores (OHSs) was undertaken. Results. Overall implant survival was 83.50% (95% confidence interval (CI) 0.79 to 0.90) at 25 years, and the number at risk was 79. Survival in male patients at 25 years was 89.5% (95% CI 0.83 to 0.96) compared to 66.9% for female patients (95% CI 0.51 to 0.83). Ten additional failures occurred in the period of ten to 25 years. These involved an adverse reaction to metal debris in four patients, a periprosthetic femoral neck fracture affecting five patients, and aseptic loosening in one patient. The median chromium levels were 49.50 nmol/l (interquartile range (IQR) 34 to 70), and the median cobalt serum levels were 42 nmol/l (IQR 24.50 to 71.25). The median OHS at last follow-up was 35 (IQR 10 to 48). During the 25-year study period, 29 patients died. Patient survival at 25 years was 75.10% (95% CI 0.67 to 0.83). Conclusion. This study demonstrates that MoM hip resurfacing using the BHR provides a durable alternative to total hip arthroplasty (THA), particularly in younger male patients with osteoarthritis wishing to maintain a high level of function. These results compare favourably to the best results for THAs. Cite this article: Bone Joint J 2024;106-B(6):540–547

Birmingham Hip resurfacings have been a popular mode of treatment for younger and more active patients with arthritis of the hip. However the use of hybrid hip arthroplasty system with a Birmingham hip resurfacing cup and modular head with a variety of cemented/uncemented stems is less well described in the literature. We analysed radiographic and clinical outcomes of 99 consecutive hybrid hip arthroplasties performed by a single surgeon between 2000 and 2006. A total of 93 patients (52 females and 41 males) with an average age of 69.9 (47 to 88) and average BMI of 28.8 (18.7 to 140.9) had arthroplasties with a mean follow up of 4.1 Yrs (1 to 6.3 years). 57 right and 42 left hip arthroplasties were performed of which 6 patients had bilateral consecutive hybrid hip arthroplasties. 93 were performed for osteoarthritis, 4 for RA, 5 patients for revision of failed hip resurfacing arthroplasties with #NOF and 1 revision for failed THR. No patients had dislocations and one patient had revision of a resurfacing cup secondary to hip pain due to excessive cup anteversion, no loosening of components were identified at the most recent follow-up and all patients were mobilising well with no complaints of pain. Hip Resurfacing procedures are gaining popularity in the younger individuals with arthrosis of the hip. Some patients who are fairly independent and active fall short of satisfying the criteria for a hip resurfacing and we preferred the option of the Birmingham hip resurfacing cup with a large modular head and a compliment of stems. This metal-on-metal option with large heads would ideally increase stability and reduce wear patterns with the prospect of increasing longevity of total hip arthroplasties

Hip resurfacing is a bone-conserving procedure with respect to proximal femoral resection, but there is debate in the literature as to whether the same holds true for the acetabulum. We have investigated whether the Birmingham hip resurfacing conserves acetabular bone. Between 1998 and 2005, 500 Birmingham hip resurfacings were performed by two surgeons. Between 1996 and 2005 they undertook 700 primary hip replacements, with an uncemented acetabular component. These patients formed the clinical material to compare acetabular component sizing. The Birmingham hip resurfacing group comprised 350 hips in men and 150 hips in women. The uncemented total hip replacement group comprised 236 hips in men and 464 hips in women. Age- and gender-matched analysis of a cohort of patients for the sizes of the acetabular components required for the two types of replacement was also undertaken. Additionally, an analysis of the sizes of the components used by each surgeon was performed. For age-matched women, the mean outside diameter of the Birmingham hip resurfacing acetabular components was 2.03 mm less than that of the acetabular components in the uncemented total hip replacements (p < 0.0001). In similarly matched men there was no significant difference (p = 0.77). A significant difference was also found between the size of acetabular components used by the two surgeons for Birmingham hip resurfacing for both men (p = 0.0015) and women (p = 0.001). In contrast, no significant difference was found between the size of acetabular components used by the two surgeons for uncemented total hip replacement in either men or women (p = 0.06 and p = 0.14, respectively). This suggests that variations in acetabular preparation also influence acetabular component size in hip resurfacing

The effects of the method of fixation and interface conditions on the biomechanics of the femoral component of the Birmingham hip resurfacing arthroplasty were examined using a highly detailed three-dimensional computer model of the hip. Stresses and strains in the proximal femur were compared for the natural femur and for the femur resurfaced with the Birmingham hip resurfacing. A comparison of cemented versus uncemented fixation showed no advantage of either with regard to bone loading. When the Birmingham hip resurfacing femoral component was fixed to bone, proximal femoral stresses and strains were non-physiological. Bone resorption was predicted in the inferomedial and superolateral bone within the Birmingham hip resurfacing shell. Resorption was limited to the superolateral region when the stem was not fixed. The increased bone strain observed adjacent to the distal stem should stimulate an increase in bone density at that location. The remodelling of bone seen during revision of failed Birmingham hip resurfacing implants appears to be consistent with the predictions of our finite element analysis

Aims. The first aim of this study was to evaluate whether preoperative renal function is associated with postoperative changes in whole blood levels of metal ions in patients who have undergone a Birmingham Hip Resurfacing (BHR) arthroplasty with a metal-on-metal bearing. The second aim was to evaluate whether exposure to increased cobalt (Co) and chromium (Cr) levels for ten years adversely affected renal function. Methods. As part of a multicentre, prospective post-approval study, whole blood samples were sent to a single specialized laboratory to determine Co and Cr levels, and the estimated glomerular filtration rate (eGFR). The study included patients with 117 unrevised unilateral BHRs. There were 36 females (31%). The mean age of the patients at the time of surgery of 51.3 years (SD 6.5), and they all had preoperative one-, four-, five-, and ten-year laboratory data. The mean follow-up was 10.1 years (SD 0.2). Results. Median Co levels at one year postoperatively increased significantly compared with the preoperative values, by a factor of 9.7, from 0.13 to 1.26 ppb (p < 0.001), and the median Cr levels increased significantly by a factor of 2.5, from 0.60 to 1.50 ppb (p < 0.001). Lower preoperative eGFRs were associated with significantly larger increases in Co at one year compared with the preoperative levels (ρ = -0.26; p = 0.005), but there was no relationship between preoperative eGFRs and changes in Cr at one year (ρ = -0.13; p = 0.153). Metal levels remained relatively constant with the passage of time, with a median ten-year value of 1.12 ppb for Co and 1.29 ppb for Cr. There was no significant relationship between the Co and Cr levels at ten-year follow-up and the change in eGFR from the preoperative level to that at ten years (ρ = -0.02; p = 0.827 for Co; ρ = -0.008; p = 0.933 for Cr). Conclusion. Although patients with lower preoperative eGFRs tended to have larger increases in Co levels at one year, increased metal levels for patients who underwent unilateral BHR did not adversely affect renal function during the first ten postoperative years. Cite this article: Bone Joint J 2024;106-B(3 Supple A):44–50

We report the survival, radiological and functional outcomes of a single surgeon series of his first 144 consecutive Birmingham hip resurfacing procedures (130 patients) at a minimum of ten years. There were ten revisions during this time. Although no patients were lost to follow-up some did not complete the scoring assessment or undergo radiological assessment at ten years. The ten-year survival for male patients was 98.0% (95% confidence interval 95.2 to 100). The ten-year survival for the total cohort with aseptic revision as the endpoint was 95.5% (95% confidence interval 91.8 to 99.0) and including revisions for sepsis was 93.5% (95% confidence interval 89.2 to 97.6). The median modified Oxford hip score at ten years was 4.2% (interquartile range 0 to 19) and the median University of California, Los Angeles score was 7.0 (interquartile range 5.0 to 8.0). This study confirms the midterm reports that metal-on-metal hip resurfacing using the Birmingham Hip provides a durable alternative to total hip replacement, particularly in younger male patients wishing to maintain a high level of function, with low risk of revision for at least ten years

Aims. It is not known whether change in patient-reported outcome measures (PROMs) over time can be predicted by factors present at surgery, or early follow-up. The aim of this study was to identify factors associated with changes in PROM status between two-year evaluation and medium-term follow-up. Patients and Methods. Patients undergoing Birmingham Hip Resurfacing completed the Veteran’s Rand 36 (VR-36), modified Harris Hip Score (mHHS), Tegner Activity Score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at two years and a minimum of three years. A change in score was assessed against minimal clinically important difference (MCID) and patient-acceptable symptom state (PASS) thresholds. Binary logistic regression was used to assess the relationship between patient factors and deterioration in PASS status between follow-ups. Results. Overall, 18% of patients reported reductions in mHHS total score exceeding MCID, and 21% reported similar reductions for WOMAC function scores. Nonetheless, almost all patients remained above PASS thresholds for WOMAC function (98%) and mHHS (93%). Overall, 66% of patients with mHHS scores < PASS at two years reported scores > PASS at latest follow-up. Conversely, 6% of patients deteriorated from > PASS to < PASS between follow-ups. Multivariable modelling indicated body mass index (BMI) > 27 kg/m. 2. , VR-36 Physical Component Score (PCS) < 51, VR-36 Mental Component Score (MCS) > 55, mHHS < 84 at two years, female sex, and bone graft use predicted these deteriorating patients with 79% accuracy and an area under the curve (AUC) of 0.84. Conclusion. Due to largely acceptable results at a later follow-up, extensive monitoring of multiple PROMs is not recommended for Birmingham Hip Resurfacing patients unless they report borderline or unacceptable hip function at two years, are female, are overweight, or received a bone graft during surgery. Cite this article: Bone Joint J 2019;101-B:1431–1437

When the Birmingham Hip Resurfacing (BHR) metal-on-metal implant system was approved by the United States Food and Drug Administration in 2006, a multicenter, prospective, post-approval study (PAS) was required. This study uses data from the PAS to investigate metal level and glomerular filtration rate (GFR) trends over the first decade in vivo. Between October 2006 and March 2011, 290 primary BHR procedures were performed among 262 patients at 5 sites. Whole blood samples were sent to a single specialized laboratory to determine GFR, cobalt (Co) and chromium (Cr) levels. The population for this study consists of 117 unrevised unilateral patients with a mean age at surgery of 51.3±6.5 years who had pre-operative, 1-year, 4-year, 5-year and 10-year laboratory data. The mean follow-up for these patients that included 36 females was 10.1±0.2 years. Median metal levels at 1-year increased relative to pre-operative values for Co (by a factor of 9.7 from 0.13 to 1.26 ppb, p<0.001) and Cr (by a factor of 2.5 from 0. 60 to 1.50 ppb, p<0.001). Metal levels subsequently remained relatively constant over time with a median 10-year value of 1.12 ppb for Co and 1.29 ppb for Cr. Based on 585 blood samples from all 117 patients, there was no relationship between GFR and Co (. →. =−0.06, p=0.14) or Cr (. →. =0.05, p=0.27) levels. However, lower pre-operative GFR values were associated with larger increases in Co at 1-year relative to the pre-operative level (. →. =−0.26, p=0.005). There was no relationship between pre-operative GFR values and changes in Cr at 1 year (. →. =−0.13, p=0.15). Through the first decade in vivo, elevated whole blood metal levels for unilateral BHR patients do not appear to adversely affect GFR. However, patients with lower pre-operative GFR values tend to have larger increases in their Co level at 1-year

We report the outcome at a minimum of five years of 110 consecutive metal-on-metal Birmingham Hip Resurfacing arthroplasties in 98 patients. The procedures were performed between October 1999 and June 2002 by one surgeon. All patients were followed up clinically and radiologically. The mean follow-up was 71 months (60 to 93). Revision of either component was defined as failure. The mean Harris Hip score at follow-up was 96.4 (53 to 100). The mean Oxford hip score was 41.9 (16 to 57) pre-operatively and 15.4 (12 to 49) post-operatively (p < 0.001). The mean University of California Los Angeles activity score was 3.91 (1 to 10) pre-operatively and 7.5 (4 to 10) post-operatively (p < 0.001). There were four failures giving a survival at five years of 96.3% (95% confidence interval 92.8 to 99.8). When applying a new method to estimate narrowing of the femoral neck we identified a 10% thinning of the femoral neck in 16 hips (14.5%), but the relevance of this finding to the long-term outcome remains unclear. These good medium-term results from an independent centre confirm the original data from Birmingham

Aims. The aim of this study was to assess the functional gain achieved following hip resurfacing arthroplasty (HRA). Patients and Methods. A total of 28 patients (23 male, five female; mean age, 56 years (25 to 73)) awaiting Birmingham HRA volunteered for this prospective gait study, with an age-matched control group of 26 healthy adults (16 male, ten female; mean age, 56 years (33 to 84)). The Oxford Hip Score (OHS) and gait analysis using an instrumented treadmill were used preoperatively and more than two years postoperatively to measure the functional change attributable to the intervention. Results. The mean OHS improved significantly from 27 to 46 points (p < 0.001) at a mean of 29 months (12 to 60) after HRA. The mean metal ion levels at a mean 32 months (13 to 60) postoperatively were 1.71 (0.77 to 4.83) µg/l (ppb) and 1.77 (0.68 to 4.16) µg/l (ppb) for cobalt and chromium, respectively. When compared with healthy controls, preoperative patients overloaded the contralateral good hip, limping significantly. After HRA, patients walked at high speeds, with symmetrical gait, statistically indistinguishable from healthy controls over almost all characteristics. The control group could only be distinguished by an increased push-off force at higher speeds, which may reflect the operative approach. Conclusion. Patients undergoing HRA improved their preoperative gait pattern of a significant limp to a symmetrical gait at high speeds and on inclines, almost indistinguishable from normal controls. HRA with an approved device offers substantial functional gains, almost indistinguishable from healthy controls. Cite this article: Bone Joint J 2019;101-B:1423–1430

Femoral neck fracture is a recognised complication of Birmingham Hip Resurfacing. But stress fracture is uncommon. Femoral neck stress fractures are one of the most difficult problems to diagnose. The pain associated with a femoral neck stress fracture often is localized poorly and may be referred to the thigh or back. We present a young fit gentleman who underwent Birmingham Hip resurfacing for Osteoarthritis Hip. He underwent Birmingham Hip Resurfacing Right side with satisfactory post-operative x-rays and progress. He presented for the Left side Birmingham Hip Resurfacing. X-rays revealed a stress fracture through the femoral neck. Patient was asymptomatic and refused any surgical intervention. Patient successfully underwent Birmingham Hip Resurfacing Left side. The Right stress fracture neck of femur healed in varus without any further complications. The patient is asymptomatic after 30 months of diagnosis. We conclude that expectant treatment has role in asymptomatic stress fracture following Birmingham Hip resurfacing

We present a consecutive case cohort of the first 100 Birmingham Hip Resurfacing (BHR)'s in 90 patients with a minimum follow up of 20 years. All procedures were performed by a single surgeon having commenced the study in 1998. The original cohort included 68 males with 75 hips (7 bilateral) and 22 females with 25 hips (3 bilateral). The mean age at index procedure was 52. Patients were recalled to review in clinic as per Medicines and Healthcare products Regulatory Agency guidelines with x-rays, metal ions and Harris Hip Scores recorded. After a minimum of 20 year follow-up review the known overall revision rate is 11%. 11 have died and 7 have been lost to review. In males the known revision rate is 4/75 (5%), 3 of which were due to early fractures and 1 revision for infection at 5 years. The known revision rate in females is 7/25 (28%) of which 6 were due to adverse reactions to metal debris; 3 at 7–8 yrs, 1 at 15 yrs, 2 at 18 years, and 1 at 2 months for avascular necrosis. The mean 20 year metal ions results were cobalt 36.6 nmol/l (range 7.4–232.1) and chromium 32.1 nmol/l (range 6–120.8). The mean Harris hip score was 88.5 (range 38.6–99.8). This case series with 20 years follow-up demonstrates excellent long term survival of the BHRs further to registry BHR data and similar to THR for same age recipients. Applying today's strict criteria for patient selection would likely improve survival rate further. BHR has not demonstrated the catastrophic revision rates associated with some metal-on-metal resurfacing and remains a safe option for those who meet the criteria

A concern of metal on metal hip resurfacing arthroplasty is long term exposure to Cobalt (Co) and Chromium (CR) wear debris from the bearing. This study compares whole blood metal ion levels from patients drawn at one-year following Birmingham Hip Resurfacing (BHR) to levels taken at a minimum 10-year follow-up. A retrospective chart review was conducted to identify all patients who underwent a BHR for osteoarthritis with a minimum 10-year follow-up. Whole blood metal ion levels were drawn at final follow-up in June 2019. These results were compared to values from patients with one-year metal ion levels. Of the 211 patients who received a BHR, 71 patients (54 males and 17 females) had long term metal ion levels assessed (mean follow-up 12.7 +/− 1.4 years). The mean Co and Cr levels for patients with unilateral BHRs (43 males and 13 females) were 3.12 ± 6.31 ug/L and 2.62 ± 2.69 ug/L, respectively, and 2.78 ± 1.02 ug/L and 1.83 ± 0.65 ug/L for patients with bilateral BHRs (11 males and 4 females). Thirty-five patients (27 male and 8 female) had metal-ion levels tested at one-year postoperatively. The mean changes in Co and Cr levels were 2.29 ug/l (p = 0.0919) and 0.57 (p = 0.1612), respectively, at one year compared to long-term. These changes were not statistically significant. This study reveals that whole blood metal ion levels do not change significantly when comparing one-year and ten-year Co and Cr levels. These ion levels appear to reach a steady state at one year. Our results also suggest that regular metal-ion testing as per current Medicines and Healthcare products Regulatory Agency (MHRA) guidelines may be impractical for asymptomatic patients. Metal-ion levels, in and of themselves, may in fact possess little utility in determining the risk of failure and should be paired with radiographic and clinical findings to determine the need for revision

We report an independent prospective review of the first 230 Birmingham hip resurfacings in 212 patients at a mean follow-up of five years (4 to 6). Two patients, one with a loose acetabular component and the other with suspected avascular necrosis of the femoral head, underwent revision. There were two deaths from unrelated causes and one patient was lost to follow-up. The survivorship with the worst-case scenario was 97.8% (95% confidence interval 95.8 to 99.5). The mean Harris hip score improved significantly (paired t-test, p < 0.05) from 62.54 (8 to 92) pre-operatively to 97.7 (61 to 100) at a mean of three years (2.1 to 4.3), then deteriorated slightly to a mean of 95.2 (47 to 100) at a mean of five years. The mean flexion improved from 91.5° (25° to 140°) to 110.4° (80° to 145°) at a mean of three years with no further improvement at five years (111.2°; 70° to 160°). On radiological review at five years, one patient had a progressive lucent line around the acetabular component and six had progressive lucent lines around the femoral component. A total of 18 femoral components (8%) had migrated into varus and those with lucent lines present migrated a mean of 3.8° (1.02° to 6.54°) more than the rest. Superolateral notching of the femoral neck and reactive sclerosis at the tip of the peg of the femoral component were associated with the presence of lucent lines (chi-squared test, p < 0.05), but not with migration of the femoral component, and are of unknown significance. Our results with the Birmingham hip resurfacing continue to be satisfactory at a mean follow-up of five years

Purpose: To find the incidence of Periprosthitic fracture following Birmingham Hip Resurfacing over the age of 65 yrs – in Ashford & St. Peters Hospitals. Method: We have done an audit to study the total number of patients who had Femoral neck fractures following Birmingham Hip Resurfacing, comparing them with the incidence of Femoral neck fracture in the age group of 65 yrs & above, from the period of March 2000 to January 2006 in Ashford & St. Peters Hospitals (NHS & Private). Between March 2000 and January 2006, 327 Birmingham hips were inserted by 8 surgeons. Fracture of the neck of the femur occurred in 5 patients, an incidence of 1.53%. Results:. 1 Intra op fracture & 4 post op fractures. Out of the total number of patients, 131 were above the age of 65years, with mean age of 68.80 years & a range of 65–77 years. No Femoral neck fractures were found in this age group. Conclusion: Incidence of Femoral neck fracture is NIL in the age group of 65 yrs & above compared to 1.53% over all

Purpose of study. This study is to determine the survival and outcomes of the Birmingham Interlocking Triple Pelvic Osteotomy. A dysplastic hip predisposes to early arthritis. The Triple Pelvic Osteotomy (TPO) is a joint-preserving option for the treatment of young adults with hip dysplasia. The long term success of the procedure is not known. Patients and methods. The senior author has been performing Birmingham Interlocking Triple Pelvic Osteotomies for 18 years. The outcomes of the first 100 patients (117 TPOs) were reviewed using postal questionnaires, telephone interviews and radiograph review. The primary outcome measure of the study was the Kaplan—Meier survival curve for the TPO. Hip replacement or resurfacing were taken as failure points. The Oxford Hip Score (OHS) and University of California, Los Angeles (UCLA) score were used as secondary outcome measures for the surviving osteotomies. The pre-and post-operative acetabular index and centre-edge angles were measured from surviving radiographs. Results. Follow-up was 93% for survivorship. The mean age at operation was 31 years (range of 7 to 57 years). The mean pre- and post-operative centre-edge angles were 19°and 50° and acetabular indices were 23° and 2°. The Kaplan-Meier survival curve demonstrates that the 10, 15 and 18-year survival rates are 76%, 57% and 50% respectively. Survival was 89% if the osteotomy was performed before 20 years of age. The median UCLA score was five (inter-quartile range three to seven). Median OHS was 41 (inter-quartile range 24 to 46). The UCLA and OHSs show that those with surviving osteotomies tend to have good hip function. Conclusions. The Birmingham Interlocking Pelvic Osteotomy provides a valuable tool to preserve dysplastic hip function and delay arthroplasty surgery, particularly in the younger patient. It is best performed early before arthritis sets in

To review the early functional results of Birmingham hip resurfacing. First 116 hips (98 patients), a cohort of consecutive patients prospectively underwent BHR in a single arthroplasty Surgeon’s practice in a University Hospital outside Birmingham. Inclusion criteria fit and active patients. 98 patients mean age 50 years (range 19–67). Pathology OA 85%, Perthes 7%, DDH 4.7% & SUFE 2%. Mean follow-up 30 months (range 12–45). Scoring systems used were Harris hip score (HHS), WOMAC & SF36. HHS: mean pre-arthroplasty 47 (range 10–73), one year 99 (n=57), at 2 years 97.3 (n=26) and at third year 100 (n=3), statistically significant improvement (P=0.001). WOMAC: pain: pre-op score 18.8, at 1 year 5.6 and second year 5.7. Stiffness: pre-op 8.5, 1 year 2.7 & 2. nd. year 2.7. Physical: 49.3, 1 year 23.4 & 2. nd. year 22.6. This shows a statistically significant improvement in pain score (p=0.025) and physical function score (p=0.025). SF-36 one-year post op, when analysed against an age/sex match control group normal values using a 2 tailed ‘t’ Test, seven of the eight domains showed no statistical significance. Only the Social Functioning domain showed a statistically significant result (p=0.011). One fracture following a fall (patient had deep cysts in proximal head now such patients are not offered BHR), one dislocation following RTA and one AVN in a 50 years old post menopausal lady. Birmingham hip resurfacing can provide excellent level of activity and patient satisfaction. A long-term study is needed to evaluate the long-term benefit and survivorship

Despite the increasing interest and subsequent published literature on hip resurfacing arthroplasty, little is known about the prevalence of its complications and in particular the less common modes of failure. The aim of this study was to identify the prevalence of failure of hip resurfacing arthroplasty and to analyse the reasons for it. From a multi-surgeon series (141 surgeons) of 5000 Birmingham hip resurfacings we have analysed the modes, prevalence, gender differences and times to failure of any hip requiring revision. To date 182 hips have been revised (3.6%). The most common cause for revision was a fracture of the neck of the femur (54 hips, prevalence 1.1%), followed by loosening of the acetabular component (32 hips, 0.6%), collapse of the femoral head/avascular necrosis (30 hips, 0.6%), loosening of the femoral component (19 hips, 0.4%), infection (17 hips, 0.3%), pain with aseptic lymphocytic vascular and associated lesions (ALVAL)/metallosis (15 hips, 0.3%), loosening of both components (five hips, 0.1%), dislocation (five hips, 0.1%) and malposition of the acetabular component (three hips, 0.1%). In two cases the cause of failure was unknown. Comparing men with women, we found the prevalence of revision to be significantly higher in women (women = 5.7%; men = 2.6%, p < 0.001). When analysing the individual modes of failure women had significantly more revisions for loosening of the acetabular component, dislocation, infection and pain/ALVAL/metallosis (p < 0.001, p = 0.004, p = 0.008, p = 0.01 respectively). The mean time to failure was 2.9 years (0.003 to 11.0) for all causes, with revision for fracture of the neck of the femur occurring earlier than other causes (mean 1.5 years, 0.02 to 11.0). There was a significantly shorter time to failure in men (mean 2.1 years, 0.4 to 8.7) compared with women (mean 3.6 years, 0.003 to 11.0) (p < 0.001)

The rate and mode of early failure in 463 Birmingham hip resurfacings in a two-centre, multisurgeon series were examined. Of the 463 patients two have died and three were lost to follow-up. The mean radiological and clinical follow-up was for 43 months (6 to 90). We have revised 13 resurfacings (2.8%) including seven for pain, three for fracture, two for dislocation and another for sepsis. Of these, nine had macroscopic and histological evidence of metallosis. The survival at five years was 95.8% (95% confidence interval (CI) 94.1 to 96.8) for revision for all causes and 96.9% (95% CI 95.5 to 98.3) for metallosis. The rate of metallosis related revision was 3.1% at five years. Risk factors for metallosis were female gender, a small femoral component, a high abduction angle and obesity. We do not advocate the use of the Birmingham Hip resurfacing procedure in patients with these risk factors

Introduction. In the early 2000s hip resurfacing became an established bone conserving hip arthroplasty option particularly for the fit and active patient cohort. The performance of second-generation metal-on-metal bearings had led to the reintroduction of hip resurfacing. The Birmingham Hip resurfacing (BHR) was introduced in 1997. This was followed by a number of different designs of the hip resurfacing. The Durom hip resurfacing was introduced in 2001. These two designs had different metallurgical properties, design parameters particularly clearance and different implantation techniques. Data from joint registries show that both prosthesis perform well. Objectives. Our objective was to perform a retrospective survival analysis comparing the Birmingham to the Durom hip resurfacing and analyse the mode of failures of the cases revised. Methods. Data was collected prospectively but analysed retrospectively. The two cohorts comprised patients treated by two senior surgeons at different units. The follow up range was 1 to 14 years with a mean of 10 years. The end-point was revision for any cause. However this was further substratified. Results. The outcome of all patients was known. The two cohorts exhibited no significant difference in demographics. No failures in either cohort were attributed to adverse reaction to metal debris. Revision for any cause was analysed by plotting Kaplan-Meier Survival curves. The Durom cohort (n=273) had 5 deaths and 9 revisions. The Birmingham cohort (n=567) had 5 deaths and 22 revisions. The Kaplan-Meier survival curves for the two resurfacing designs were different. The Durom cohort demonstrated a concave curve with more early failures. This was contrary to the BHR's convex curve with higher incidence of late failures. We analysed the data by substratifying into failure of femoral or acetabular component and neck fractures. Conclusions. The Kaplan-Meier survival analysis demonstrates that the Durom hip resurfacings had a higher rate of early failure. However extrapolation of the curves suggests that the Durom may have a superior long term survival compared to the BHR. We postulate that this may be due to the femoral implantation technique with less late failures in Duroms and an apparent acceleration of failures in BHR cohort around the ten year stage. Joint registry data also reflect this pattern

The purpose of this study is to show our experience with Birmingham Hip Resurfacing which we think it is a procedure that will play a big role in hip replacement surgery, especially for young people. Methods:. Operative Records from the Theatre Registrar Book, Implant register Book and the theatre computer records. Other similar studies from other Hospitals. Birmingham Hip Resurfacing – Ashford and St. Peter’s Hospitals Experience for the period March 2000 to January 2004. The total number of cases done for the period: 290. The number of patients: 277. Male: 160. Female: 130. Right Hip: 145. Left Hip: 120. Side not recorded: 25. Both sides done: 13. Primary cases: 286. Revisions: 4. The youngest male done aged: 25 years. The youngest female done aged: 33 years. The oldest male done aged: 75 years. The oldest female done aged: 72 years. Mean age: 56.5 years. Conclusion: Birmingham Metal on Metal Resurfacing started by Mr. Derek McMinn at about 13 years ago. Our results and results world-wide are encouraging. The failure rate of THR in young patients is very high, and the revision is difficult and requires a major reconstructive operation. Therefore BHR is a good alternative in our opinion

We describe the experience with the first consecutive 230 Birmingham hip resurfacings at our centre. At a mean follow-up of three years (25 to 52 months) survivorship was 99.14% with revision in one patient for a loose acetabular component and one death from unrelated causes. One patient developed a fracture of the femoral neck at six weeks which united unremarkably after a period of non-weight-bearing. The Harris hip score improved from a mean of 62.54 (8 to 92) to 97.74 (61 to 100). The mean flexion improved from 91.52° (25 to 140) to 110.41° (80 to 145). Most patients (97%) considered the outcome to be good or excellent. Our preliminary experience with this implant is encouraging and the results are superior to the earlier generation of resurfacings for the same length of follow-up

Modern Metal on Metal hip resurfacing originated from Birmingham in the early 1990’s and is now well estabilished in the U.K. This procdure is gaining acceptance in other parts of the world and is now being performed in many countries in the Asia Pacific region including Australia and India.The demographics of the patient population with hip arthritis in south Asia and western europe is very contrasting. Primary osteoarthritis of the hip is virtually non-existent in the Indian subcontinent wheras it is by far the commonest hip disorder in Europe.Sixty nine percent of patients had primary osteoarthritis as the presenting pathology in the pilot series of metal on metal hip resurfacings from Birmingham. Most patiens in India with hip arthritis are very young and have developed secondary degenerative in the joint due to other specific causes. Thus procedures like the Birminham hip resurfacing which addresses the difficult problem of hip arthritis in the young active adult have a greater role to play in this

We report a 12- to 15-year implant survival assessment of a prospective single-surgeon series of Birmingham Hip Resurfacings (BHRs). The earliest 1000 consecutive BHRs including 288 women (335 hips) and 598 men (665 hips) of all ages and diagnoses with no exclusions were prospectively followed-up with postal questionnaires, of whom the first 402 BHRs (350 patients) also had clinical and radiological review. Mean follow-up was 13.7 years (12.3 to 15.3). In total, 59 patients (68 hips) died 0.7 to 12.6 years following surgery from unrelated causes. There were 38 revisions, 0.1 to 13.9 years (median 8.7) following operation, including 17 femoral failures (1.7%) and seven each of infections, soft-tissue reactions and other causes. With revision for any reason as the end-point Kaplan–Meier survival analysis showed 97.4% (95% confidence interval (CI) 96.9 to 97.9) and 95.8% (95% CI 95.1 to 96.5) survival at ten and 15 years, respectively. Radiological assessment showed 11 (3.5%) femoral and 13 (4.1%) acetabular radiolucencies which were not deemed failures and one radiological femoral failure (0.3%). . Our study shows that the performance of the BHR continues to be good at 12- to 15-year follow-up. Men have better implant survival (98.0%; 95% CI 97.4 to 98.6) at 15 years than women (91.5%; 95% CI 89.8 to 93.2), and women < 60 years (90.5%; 95% CI 88.3 to 92.7) fare worse than others. Hip dysplasia and osteonecrosis are risk factors for failure. Patients under 50 years with osteoarthritis fare best (99.4%; 95% CI 98.8 to 100 survival at 15 years), with no failures in men in this group. Cite this article: Bone Joint J 2014;96-B:1298–1306

The Articular Surface Replacement (ASR) hip resurfacing arthroplasty has a failure rate of 12.0% at five years, compared with 4.3% for the Birmingham Hip Resurfacing (BHR). We analysed 66 ASR and 64 BHR explanted metal-on-metal hip replacements with the aim of understanding their mechanisms of failure. We measured the linear wear rates of the acetabular and femoral components and analysed the clinical cause of failure, pre-revision blood metal ion levels and orientation of the acetabular component. There was no significant difference in metal ion levels (chromium, p = 0.82; cobalt, p = 0.40) or head wear rate (p = 0.14) between the two groups. The ASR had a significantly increased rate of wear of the acetabular component (p = 0.03) and a significantly increased occurrence of edge loading (p < 0.005), which can be attributed to differences in design between the ASR and BHR. The effects of differences in design on the in vivo wear rates are discussed: these may provide an explanation as to why the ASR is more sensitive to suboptimal positioning than the BHR

Introduction: The Birmingham Hip Resurfacing (BHR) system comprises both a BHR femoral head and a large modular femoral head for use should a total hip replacement be required. The modular femoral head has identical material chemistry, microstructure, spherical form, and surface roughness of the bearing surfaces of resurfacing femoral head and both BHR and THR devices share the same acetabular components. Hence, if the femoral component of a BHR needs revision surgery, the Birmingham hip system provides the potential of converting it to a THR without the need to also revise the well fixed cup. Although it stands to reason that the wear behaviour of the BHR and Birmingham THR will be similar, it is important to investigate the wear behaviour of new THR modular heads against worn BHR cups, representing revision of BHR to Birmingham THR without cup revision. The aim of this study is to assess the viability of the femoral component revision for BHR devices whilst leaving the acetabular components in situ in the pelvis. Materials and Methods: The wear and friction tests were conducted with pristine modular heads paired with BHR cups which had already undergone 5 million cycles (Mc) of wear in a hip simulator against BHR heads. Results and Discussions: The average wear rate of the new Birmingham THR modular heads against worn cups was 0.42 mm. 3. /Mc whilst the new BHR heads against new cups generated wear rate of 0.67 mm. 3. /Mc. Supported by the friction test results, it indicated that the new femoral heads paired with worn cup did not negatively affect the substantial amount of fluid-film lubrication that had developed over the course of the original test. Therefore, it is acceptable to use new femoral heads against worn cups, if the cups are not damaged, well fixed and correctly orientated

Introduction: Femoral neck failure due to avascular necrosis (AVN) is one of the most significant complications following resurfacing hip arthroplasty. It is likely that the surgical approach is one of the factors influenc-ing the development of AVN. Positron emission tomography (PET) is the only form of imaging that allows visualisation of bone metabolic activity deep to a metal surface. Objectives: To establish the reliability and accuracy of PET using fluorine-18 to evaluate viability of the femoral head and neck after resurfacing hip arthroplasty. To assess the viability of ten proximal femora after Birmingham resurfacing hip arthroplasty via a modified lateral approach. Design: A convenience case series of ten patients taken from the first fifteen from one orthopaedic surgeon’s experience of Birmingham resurfacing hip arthroplasty. Setting: The PET unit of a major urban teaching hospital with a large academic orthopaedic department. Participants: Patients that had undergone unilateral Birmingham resurfacing hip arthroplasty via a modified lateral approach were asked to volunteer for the study. The main criterion for inclusion was ease of attendance for imaging. Intervention: Participants were given a single intravenous dose of 250MBq fluorine-18. After a period of 40 minutes uptake time, PET images of adjacent, sequential 10cm transverse sections including both acetabulae and proximal femora were obtained. Main Outcome Measures: Images were reconstructed to allow relative quantification of uptake between operated and non-operated femoral heads and necks. Results: PET imaging was successful in all subjects and demonstrated activity within the resurfaced femoral heads and femoral necks. No evidence of AVN was found. Conclusions: Static positron emission tomography using fluorine-18 is an accurate and reliable method of assessing femoral head and neck viability after resurfacing hip arthroplasty. No evidence of avascular necrosis was found in this initial series of patients that had undergone Birmingham resurfacing hip arthroplasty via a modified lateral approach

Introduction: Hip Resurfacing has always been an attractive concept for the treatment of hip arthritis in young patients. Excellent early and medium-term results have been reported with the Birmingham Hip Resurfacing (BHR) device in single and multi-surgeon all-diagnoses and OA series. In the present report we present the results of BHR in inflammatory arthritis. Methods: This is a single-surgeon consecutive series. There were 15 consecutive hips (12 patients) including 2 women (2 hips) with ankylosing spondylitis (AS) operated at a mean age of 41.7 years (range 29.5 to 54.3 years). Fortytwo hips (31 patients) with seronegative or rheumatoid (RA) arthritis treated with a BHR at a mean age of 40 (13 to 64) years and a follow-up of 2 to 9 (mean 5.9) years were also studied. One patient died 5 years later. Revision for any reason was the end-point and unrevised patients were assessed with Oxford hip scores and reviewed clinico-radiologically with AP and lateral radiographs. Results: In the RA group there was one failure from femoral neck fracture two months after operation giving a failure rate of 2.4%. There were no failures in this cohort at a follow-up of 1.8 to 8.8 (mean 4.9) years. As a combined group the failure rate of BHRs in inflammatory arthritis is 1.75% and the cumulative survivorship at 9 years is 98.2% (figure). Discussion: The good results of Birmingham Hip Resurfacing in inflammatory arthritis in this relatively young cohort of patients make this a viable treatment option for these patients. Selection of patients with a reason-able bone quality and adherence to precise operative technique are vital to the success of this procedure

Introduction: The Birmingham Hip resurfacing was commercially introduced in 1997 and early originating centre series show good functional outcomes. Concerns have been raised over the longevity, functional outcomes and metal ion release from the implants. There are no series of medium term results from an independent district general hospital reported in the literature. We present a prospective series of 100 patients with mean 5 year follow up from a district general hospital. Each patient underwent yearly clinical, hip scoring, and regular radiographic evaluation. Radiographic analysis was undertaken using Harris’, Hodgkinson’s and Amstutz’s criteria, evaluation of component position, neck narrowing and migration using diagnostic PACS workstations with standardised scaled images. Results: Between June 2001 and Feb 2004 100 Birmingham Hip replacements were performed by two consultant surgeons (MP, AA). Mean follow up is 61.2 months (range 38–76 months). Harris hip scores (fig 1) improved from 46 pre-operatively to 90 post-operatively and no significant change over the next five years. There were no revisions in this period. Obese patients (BMI> 30) had a significantly (p< 0.03) lower post operative functional score as compared normal patients. No other factors were significant for outcome. Component position was satisfactory in 93% of cases. Radiographic analysis showed no cups, or stems were definitely loose. Radiolucent lines were present in 8/100 acetabular and 3/100 femoral components, osteolytic lesions were seen in three acetabular components. Mean neck narrowing was 9mm. No patients show any radiographic evidence of avascular necrosis. Conclusion This independent series shows the results of the Birmingham hip resurfacing are reproducible and comparable to those reported in the originating centre. The Birmingham hip resurfacing gives excellent clinical results, and there is no early evidence of radiographic failure. The high rate of neck narrowing gives us cause for concern and we would recommend regular radiographic follow up

Introduction: Although resurfacing hip replacements are widely used there are few little independent outcome data to support this. The aim of this study was to report the 5 year clinical outcome and 7 year survival of an independent series. Method: 610 Birmingham hip resurfacings were implanted in 532 patients with an average age of 51.8 years (range 16.5–81.6 years) and were followed for between 2 to 8 years; 120 of this series had minimum five year follow-up. Two patients were lost. There were 23 revisions, giving an overall survival of 95% (95% CI 85–99%) at seven years. Fractured neck of femur (n=13) was the most common reason for revision, followed by aseptic loosening (n=4). There were also 3 patients who had failures that were possibly related to metal debris. At a minimum of 5 year follow-up 93% had excellent or good outcome according to the Harris Hip Score. The mean Oxford Hip Score was 16.1 points (SD 7.7) and the mean UCLA activity score was 6.6 points (SD 1.9). There were no patients with definite evidence of radiographic loosening or greater than 10% of neck narrowing. Discussion: The results demonstrate that with the Birmingham Hip Resurfacing, implanted using the extended posterior approach, the five year survival is similar or better to the reported survival rates for cemented and hybrid THR’s in young patients. Conclusions: Considering these patients are young and active these results are good and support the use of resurfacing. However, further study is needed to address the early failures; particularly those related to fracture and metal debris

Aims: To review the early results of Birmingham hip resurfacing (BHR). First 116 hips (98 patients). Materials: A cohort of consecutive patients prospectively underwent BHR in a single arthroplasty Surgeonñs practice in a University Hospital out side Birmingham. Inclusion criteria þt and active patients expected to out live conventional THR. 98 patients mean age 50 years (range 19–67). Pathology OA 85%, Perthes 7%, DDH 4.7% & SUFE 2%. Mean follow-up 30 months (range 12–45). Scoring systems used were Harris hip score (HHS), WOMAC & SF 36. Results: All patients under review, no radiological loosening. HHS:Mean pre-arthroplasty score 47 (range 10–73), 1 yr score 99 (n=38), 2yr 97.3 (n=30) at 3yr 100 (n=26) & 4th yr 100 (n=4), this shows a statistically signiþcant improvement (P=0.001). WOMAC: Pain: pre-op score 18.8, at 1 year 5.6 & 2nd year 5.7. Stiffness: pre-op 8.5, 1 year 2.7 & 2nd year 2.7. Physical: 49.3, 1 year 23.4 & 2nd year 22.6. This shows a statistically signiþcant improvement in score (p=0.025) SF-36 Analysed against an age/sex match control group of normal values using a 2 tailed Ôtñ Test, seven of the eight domains showed no statistical signiþcant difference. Complications: One fracture following a fall, 2 AVN & early fractures (patients had deep cysts in proximal head now such patients are not offered BHR), one dislocation following RTA Conclusions: Birmingham hip resurfacing can provide excellent level of activity and patient satisfaction. Careful patient selection is needed. A long-term study is needed to evaluate the long-term beneþt and survivorship

Few independent studies have reported the outcome of resurfacing arthroplasty of the hip. The aim of this study was to report the five-year clinical outcome and seven-year survival of an independent series. A total of 610 Birmingham Hip Resurfacing arthroplasties were performed in 532 patients with a mean age of 51.8 years (16.5 to 81.6). They were followed for between two and eight years; 107 patients (120 hips) had been followed up for more than five years. Two patients were lost to follow-up. At a minimum of five years’ follow-up, 79 of 85 hips (93%) had an excellent or good outcome according to the Harris hip score. The mean Oxford hip score was 16.1 points (. sd. 7.7) and the mean University of California Los Angeles activity score was 6.6 points (. sd. 1.9). There were no patients with definite radiological evidence of loosening or of narrowing of the femoral neck exceeding 10% of its width. There were 23 revisions (3.8%), giving an overall survival of 95% (95% confidence interval 85.3 to 99.2) at seven years. Fractured neck of femur in 12 hips was the most common indication for revision, followed by aseptic loosening in four. In three hips (three patients) (0.5%), failure was possibly related to metal debris. Considering that these patients are young and active these results are good, and support the use of resurfacing. Further study is needed to address the early failures, particularly those related to fracture and metal debris

Between April 1999 and April 2004, 3497 Birmingham hips were inserted by 89 surgeons. Fracture of the neck of the femur occurred in 50 patients, an incidence of 1.46%. Complete data were available for 45 patients in whom the incidence was 1.91% for women and 0.98% for men. The relative risk of fracture for women vs men was 1.94961 and this was statistically significant (p < 0.01). The mean time to fracture was 15.4 weeks. In women the fractures occurred at a mean of 18.5 weeks and were more likely to have been preceded by a pro-dromal phase of pain and limping. In men the mean time to fracture was 13.5 weeks. Significant varus placement of the femoral component, intra-operative notching of the femoral neck and technical problems were common factors in 85% of cases

The Birmingham hip resurfacing metal-on-metal arthroplasty was introduced in 1997 and has shown promising short- to mid-term results. We used radiostereophotogrammetric analysis (RSA) to study the stability of 20 resurfacing arthroplasties over a follow-up period of 24 months. Radiological examinations for RSA were performed immediately after surgery and at two, six, 12 and 24 months after operation. Precision and detection of migration thresholds (non-zero movement) were calculated. All the results corresponded well to those found in similar experimental arrangements with standard hip prostheses. Migration of the cup and vertical and mediolateral migration of the head were calculated. The values were low at two years compared with those of earlier studies of cemented femoral components in conventional total hip replacements indicating that there was no evidence of excessive early migration or loosening of the components

The early designs of hip resurfacing implants suffered high rates of early failure, making it impossible to obtain valuable mid-term radiostereophotogrammetric (RSA) results. The metal-on-metal Birmingham Hip Resurfacing arthroplasty has shown promising mid-term results and we present here the first mid-term RSA analysis of a hip resurfacing implant. The analysis was performed in 19 hips at five years post-operatively. The mean acetabular component translation and rotation, and femoral component translation were compared with the previous RSA measurements at two and six months, and one and two years. There was no statistical significance (t-test, p ≤ 0.05) between these consecutive movements, indicating the mid-term stability of the implant

Aim: The purpose of this study was to analyze the in-vivo wear rates of Birmingham Hip Resurfacing (BHR, Midland Medical Technologies Ltd., Birmingham, U.K.) explants and to contrast the results to the wear rates of conventional 28 mm metal-on-metal bearings (Metasul, Zimmer GmbH, Winterthur, Switzerland). Methods: The wear rates, measured by a coordinate measuring machine (CMM5, SIP, Geneva, Switzerland), of 6 femoral components and two complete pairings of the BHR retrieved from 8 hips were contrasted to 43 28 mm heads from second generation metal-on-metal bearings (Metasul, Sulzer Orthopaedics Ltd., Winterthur, Switzerland). Results: After 13 months (7 to 24) the BHR femoral heads showed a median volumetric wear rate of 2.9 mm. 3. (interquartile range: 0.8 to 7.1), slightly, but not significantly higher than the investigated 43 28mm Metasul heads (0.8 mm. 3. /year, p = 0.067, 14 months [7 to 24] in-situ). One BHR case with a cup abduction angle of 70° showed a significant higher wear rate of 17.8 mm. 3. All BHR cases showed only small amounts of metallic particle histological and correspondingly, a mild histiocytic tissue response without foreign body granuloma formation. Discussion: During the first two years after surgery the investigated BHR components showed wear rates substantially lower than conventional polyethylene bearings, comparable to Metasul bearings, implanted with very successful clinical results. But whether the wear rates will drop down after the so called running-in period comparable to conventional metal-on-metal bearings and provide young and active patients with a biologically acceptable particle volume over a long time period, still remains to be seen

We present the results of our initial experience with the use of the Birmingham metal-on-metal Hip Resurfacing. The Birmingham Hip Resurfacing(BHR) consists of a high carbon chrome cobalt uncemented hydroxyapatite cupand a cemented femoral component. For patients with severe dysplasia adysplasia cup with screws was used. We utilise this kind of prosthesis for the younger patients (< 65 year). Excellent clinical results are encountered; none of the early problems aswith the old Wagner resurfacing (metal-on-poly) are seen. Our early results are similar to the encouraging results of the series of D.McMinn/R.Treacy. From September 1998 through April 2001, 185 BHR arthroplasties were performed. The mean age was 49.7 year (16–75). More male patients were operated with this method than female patients (64%–36%). The aetiology was osteoarthritis (81%), necrosis (9%), dysplasia (CDH) (6.6%). Results: The last 115 patients were reviewed with a follow up from 1 month to 2.5year. Only two patients were lost for follow-up because of death. There was no pain in 92.3% of the cases. The total Harris Hip Score had a mean of97.91, a median score of 100 (71–100). Merle d’Aubigné total Score was 17.36 (12–18). There was a strenuous activity in 70.2% of the patients. The mean length of stay in hospital was six days (range: 2–26). Complications were: One fractured neck of femur, one ischial nerve palsy and one guide pin was left in the femur. All patients were followed on regular basis and the X-rays were studied for angle of preoperative neck of femur, postoperative angle of the femoral component, angle of cup placement and the parallelism of both components. Conclusion: Performing only alternate bearings in patients under the age of 75, the metal-on-metal Birmingham Hip Resurfacing looks a good alternative in young active patients and the results are promising

My experience with Birmingham Hip Resurfacing began in July 2000 and continues to this day for selected cases including OA, AVN, CDH and also following old fracture deformity and Femoral/Pelvic osteotomy. Early on, the criteria for patient selection expanded with increasing experience and positive acceptance by patients but then moderated as adverse reports including those from our National Joint Replacement Registry suggested a need for caution with Surface Replacement. Over 10 years, (July 2000 — July 2010), a personal series of 243 BHRs were followed (169 male — 74 female) with only one return to theatre in that time (4 days post op. to revise a poorly seated acetabular cup in a dysplastic socket). There were no femoral neck fractures in that 10 year period but 3 femoral cap/stem lucencies were known (2 female-1 male) with insignificant symptoms to require revision. The complete 10 year series of cases were then matched in the Australian National Joint Replacement Registry. No other revisions were identified by the Registry for all 243 cases. Soon after completing this encouraging outcome study however 3 revision procedures have been necessary (2 for sudden late head/neck failure including one of the three with known cap/stem lucencies and one for suspected pseudotumour/ALVAL). One healing stress fracture of the femoral neck and another further cap/stem loosening have also presented recently but with little in the way of symptoms at this stage. Surprisingly, there is little indication which case is likely to present with problems even in the presence of many cases done earlier where one would be cautious now to use a BHR but which have ongoing good outcomes. (e.g., AVN or the elderly osteoporotic patient). My journey therefore with Birmingham Hip Resurfacing over that first 10 years has been very positive and I believe it retains an important place for the younger patient with good bone quality. However it has become only recently apparent in my series of 243 cases that late onset unpredictable problems can arise which is likely to further narrow my selection criteria for this procedure. The likely outcome will be that it will have a more limited place in my joint replacement practice despite the very positive early experience

Hip resurfacing is being performed more frequently in the United Kingdom. The possible benefits include more accurate restoration of leg length, femoral offset and femoral anteversion than occurs after total hip arthroplasty (THA). We compared anteroposterior radiographs from 26 patients who had undergone hybrid THA (uncemented cup/cemented stem), with 28 who had undergone Birmingham Hip Resurfacing arthroplasty (BHR). We measured the femoral offset, femoral length, acetabular offset and acetabular height with reference to the normal contralateral hip. The data were analysed by paired t-tests. There was a significant reduction in femoral offset (p = 0.0004) and increase in length (p = 0.001) in the BHR group. In the THA group, there was a significant reduction in acetabular offset (p = 0.0003), but femoral offset and overall hip length were restored accurately. We conclude that hip resurfacing does not restore hip mechanics as accurately as THA

We compared the medium-term clinical and radiological results of hybrid total hip replacement (THR) with metal-on-metal Birmingham hip resurfacing (BHR) in two groups of 54 young patients matched for age, gender, body mass index and pre-operative levels of activity. The clinical outcome was assessed by the University of California, Los Angeles (UCLA) activity score, the Oxford Hip Score (OHS) and the EuroQol scores. Radiologically, all hips were assessed for migration and osteolysis, the hybrid THRs for polyethylene wear and the BHRs for a pedestal sign. The mean follow-up of the patients with a hybrid THR was ten years and for those with a BHR, nine years. Four patients with a hybrid THR and one with a BHR had died. In each group five were lost to follow-up. The revision rate of the hybrid THRs was 16.7% (9 of 54) and of the BHRs 9.3% (5 of 54) (p = 0.195). Radiographs of a further eight hybrid THRs demonstrated wear and osteolysis, and they await revision (p = 0.008). Of the unrevised BHRs 90% had radiological changes, of which approximately 50% had progressed over the previous four years. All hybrid THRs demonstrated linear polyethylene wear with a mean of 1.24 mm (0.06 to 3.03). The BHRs recorded superior OHS (p = 0.013), UCLA (p = 0.008), and EuroQol visual analogue scores (p = 0.009). After nine years, patients with BHRs remained more active and had a lower rate of revision than those with hybrid THRs. Both groups demonstrated progressive radiological changes at medium-term follow-up

The dysplasia cup, which was devised as an adjunct to the Birmingham Hip Resurfacing system, has a hydroxyapatite-coated porous surface and two supplementary neutralisation screws to provide stable primary fixation, permit early weight-bearing, and allow incorporation of morcellised autograft without the need for structural bone grafting. A total of 110 consecutive dysplasia resurfacing arthroplasties in 103 patients (55 men and 48 women) performed between 1997 and 2000 was reviewed with a minimum follow-up of six years. The mean age at operation was 47.2 years (21 to 62) and 104 hips (94%) were Crowe grade II or III. During the mean follow-up of 7.8 years (6 to 9.6), three hips (2.7%) were converted to a total hip replacement at a mean of 3.9 years (2 months to 8.1 years), giving a cumulative survival of 95.2% at nine years (95% confidence interval 89 to 100). The revisions were due to a fracture of the femoral neck, a collapse of the femoral head and a deep infection. There was no aseptic loosening or osteolysis of the acetabular component associated with either of the revisions performed for failure of the femoral component. No patient is awaiting a revision. The median Oxford hip score in 98 patients with surviving hips at the final review was 13 and the 10th and the 90th percentiles were 12 and 23, respectively

A cadaver study using six pairs of lower limbs was conducted to investigate the accuracy of computer navigation and standard instrumentation for the placement of the Birmingham Hip Resurfacing femoral component. The aim was to place all the femoral components with a stem-shaft angle of 135°. The mean stem-shaft angle obtained in the standard instrumentation group was 127.7° (120° to 132°), compared with 133.3° (131° to 139°) in the computer navigation group (p = 0.03). The scatter obtained with computer-assisted navigation was approximately half that found using the conventional jig. Computer navigation was more accurate and more consistent in its placement of the femoral component than standard instrumentation. We suggest that image-free computer-assisted navigation may have an application in aligning the femoral component during hip resurfacing

Introduction: Hip resurfacing has undergone a resurgence of interest in the past five years. With it, the awareness of femoral neck fractures associated with this prosthesis has grown. We report the first national review of femoral neck fractures over a four-year period. Method: All surgeons using the Birmingham hip resurfacing in Australia were contacted and asked to supply details of any femoral neck fractures they had experienced. Routine co-morbidities and demographics were collated. Results: Fifty fractures have occurred in the time period. The fracture rate was twice as high in women than men and this was statistically significant (p< 0.001). Mean time to fracture was 15 weeks and was slightly longer in women than men. Technical difficulties included notching of the femoral neck, varus placement of the femoral prosthesis, poor exposure due to obesity and poor impaction of the femoral component. Conclusions: The national fracture rate associated with the Birmingham hip resurfacing is 1.46%

The use of Birmingham hip resurfacing (BHR) remains controversial due to the increased revision rate in female patients. We compared the outcomes of BHR in female patients to an age matched total hip arthroplasty(THA) cohort. We reviewed the pain, function and total Harris Hip Scores(HHS), and Kaplan-Meir survivorship for BHR and THA cohorts from a prospective regional arthroplasty database. There were 234 patients in each cohort, with mean age of 51 years. The BHR cohort had significantly better function and total HHS at all points of the 5-year study, but not for the post-operative pain score. The 5-year revision rate for the BHR cohort was significantly higher than the THA cohort (6.8% vs 3.4%, p=0.001). The main reason for revision in the BHR cohort was aseptic loosening (n=8), followed by metallosis (n=3). The 5-year Kaplan-Meier survivorship was 92.6% (95% CI±1.7%) and 96.4% (95% CI±1.3%) for the BHR and THA cohort (p=0.001). BHR can give significantly better functional outcomes than THA. The vast majority of female patients were happy with BHR and did not need further surgery at the 5-year stage. This is somewhat at odds with the recent reputation of the procedure. The 10-year result of the same cohort is warranted to provide further data. Our study is not a recommendation to still offer BHR to female patients, but rather to inject a note of realism into the debate. There are implications for future implant development in that these results do validate resurfacing as a functionally valuable option for active patients

This is a longitudinal study of the daily urinary output and the concentrations in whole blood of cobalt and chromium in patients with metal-on-metal resurfacings over a period of four years. Twelve-hour urine collections and whole blood specimens were collected before and periodically after a Birmingham hip resurfacing in 26 patients. All ion analyses were carried out using a high-resolution inductively-coupled plasma mass spectrometer. Clinical and radiological assessment, hip function scoring and activity level assessment revealed excellent hip function. There was a significant early increase in urinary metal output, reaching a peak at six months for cobalt and one year for chromium post-operatively. There was thereafter a steady decrease in the median urinary output of cobalt over the following three years, although the differences are not statistically significant. The mean whole blood levels of cobalt and chromium also showed a significant increase between the pre-operative and one-year post-operative periods. The blood levels then decreased to a lower level at four years, compared with the one-year levels. This late reduction was statistically significant for chromium but not for cobalt. The effects of systemic metal ion exposure in patients with metal-on-metal resurfacing arthroplasties continue to be a matter of concern. The levels in this study provide a baseline against which the in vivo wear performance of newer bearings can be compared

We compared the long-term clinical and radiological results of hybrid total hip replacement (THR) with metal-on-metal Birmingham hip resurfacing (BHR) in two groups of 54 young patients matched for age, gender, body mass index and pre-operative levels of activity. The clinical outcome was assessed by the University of California, Los Angeles (UCLA) activity score, the Oxford Hip Score (OHS) and the EuroQol scores. Radiologically, all hips were assessed for migration and osteolysis, the hybrid THRs for polyethylene wear and the BHRs for a pedestal sign. The mean follow-up of the patients with a hybrid THR was 16 years and for those with a BHR, 15 years. 12 patients with a hybrid THR and 6 with a BHR had died. 2 patients with a BHR refused follow up but remain unrevised and 5 were lost to follow-up, as was 1 with a hybrid THR. The revision rate of the hybrid THRs was 28% (15 of 54) and of the BHRs 11% (6 of 54) (p = 0.029). Radiographs of a further 13 hybrid THRs demonstrated wear and osteolysis but are functioning well and are under observation. Of the unrevised BHRs 96% had radiological changes, of which approximately 17% had progressed over the previous 6 years. All hybrid THRs demonstrated linear polyethylene wear with a mean of 1.84mm (0.06 to 2.6). The BHRs recorded superior OHS (p = 0.03), UCLA (p = 0.0096), and EuroQol visual analogue scores (p = 0.03). After 15 years, patients with BHRs remained more active and had a lower rate of revision and death than those with hybrid THRs. Both groups demonstrated progressive radiological changes at long-term follow-up

Background: Metal on metal resurfacing of the hip is an attractive conservative treatment option for the younger, active arthritic patient. It has the advantages of bone preservation and the longevity of metal bearing surfaces. Concerns remain over the performance of these implants due to historical failure of similar devices. The possible longer-term survival of these implants can only be justified if the early results are as successful as conventional hip replacement. Patients & Methods: The clinical and radiological follow-up of our first 25 consecutive resurfacing patients is presented. The Birmingham Hip Resurfacing prosthesis (Midland Medical Technologies, Birmingham, UK) was used, and all procedures performed by the senior author (EHM). Clinical assessment was done using the modified Harris Hip Score, and functional outcomes measured using the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC). Radiographs were examined for radioleucent lines, migration of components, osteolysis and heterotropic ossification. Results: 28 primary hip resurfacings in 25 patients were reviewed. The mean follow up period was 18 mts (12– 36mts). The mean age of patients at time of operation was 51yrs (37–64 yrs). Main indication for surgery was Osteoarthrosis. The mean Harris Hip Score improved from 44 preoperative, to 94.5 postoperative. The mean preoperative WOMAC score was 30 and the mean postoperative score 88.The average duration of hospital stay was 5 days, and the average operative blood loss 3g %. All patients in paid employment returned to work at an average of 8 weeks postoperatively, and majority of patients are able to participate in sports and recreational activities. There were no cases of dislocations, femoral neck fractures, avascular necrosis or osteolysis. Conclusion: Hip resurfacing using metal on metal hybrid fixed components, offers a viable treatment alternative in younger active patients. Early outcomes are at least comparable to total hip replacement in terms of pain relief and restoration of function. Despite the lack of long-term data, the relative absence of complications and the potential benefits justify its continued use. We believe the future is very promising for this procedure

Aim: We present the outcome of Birmingham Hip Resurfacing Arthroplasty performed by a single surgeon after at least five years follow up. Patients and Methods: One hundred hips in 84 patients were studied with a mean follow-up of 6.4 years (5–8.3 years), performed by a single surgeon. Three patients died of unrelated causes and 2 patients were lost to follow-up, hence the study group comprised of 79 patients with 95 hips. Birmingham resurfacing femoral and acetabular components were used in all patients. The clinical outcome was measured using Harris, Charnley, Oxford hip scores and quality of life using SF-36. Radiographs were systematically analysed for implant position, fixation, and loosening. Results: The mean age was 54 years (20–74years) and BMI of 28 (19–35). Primary osteoarthritis was seen in 69 hips. Six patients (6.1%) underwent revision of the femoral component (3 for peri-prosthetic fractures of the neck of femur, 2 for deep infection and 1 for collapse due to AVN). None of the patients had evidence of loosening around the acetabular component and femoral components in 28 patients. Type 1 pedestal sign was seen in 61 hips and Type 2 in 2 hips. The clinical scores were respectively, Harris 85 (25–100), Oxford 21.5 (12–52), mean Charnley score 4.8 for pain, 5.3 for movement and 4.3 for mobility; the mean SF-36 score were 44 (12–58) for the physical and 51.4 (19–71) for the mental component. With an end point of definite or probable aseptic loosening, the probability of survival at 5 years was 100% and 97.3% (95% CI = 2.9) for acetabular and femoral components respectively. Overall survival at 5years with removal or repeat revision of either component for any reason as the end point was 91% (95% CI: 82 to 97%). Conclusion: The results of this study support the continued use of Birmingham Hip Resurfacing Arthroplasty in young active individuals. As loosening can occur as a late phenomenon, a longer follow up is needed to determine longevity, durability of this prosthesis

Thirty nine Birmingham Resurfacing Hip Replacements were inserted between March 1999 and December 2000. The very early results are very satisfactory in a high demand group of patients. Because of the relative ease of revision the implants have a role as a “pre” total hip replacement. The also have an important role in cases such as osteopetrosis and previous femoral osteotomy were an intra medullary stem is difficult. The series includes two cases of arthrodesis take down. Complications have included one dislocation in a patient with cerebral palsy and one intra operative fractured neck of femur. However, the early studies suggest that the large metal on metal bearing does produce serum chrome and cobalt levels which may be elevated in comparison with Metasul bearings at one year. The clinical significance of this is unknown

The Birmingham hip resurfacing (BHR) arthroplasty is a metal-on-metal prosthesis for which no medium- or long-term results have been published. Despite this, it is increasing in popularity as an alternative to stemmed prostheses for younger patients. Since the fixation of the socket is conventional, the major concern is long-term failure of the femoral component. This can be predicted by the use of roentgen stereophotogrammetric analysis (RSA). We have therefore undertaken such a study of the BHR femoral component over a period of two years. Twenty patients (22 hips) underwent a standard BHR procedure. Migration of the femoral component was measured by RSA at intervals of three, six, 12 and 24 months. At 24 months the total three-dimensional migration of the head was 0.2 mm. This was not statistically significant. Previous studies have shown that implants which loosen quickly have rapid early migration. Our results therefore suggest that the BHR femoral component is an inherently stable device which is likely to perform well in the long term

There has been renewed interest in metal-on-metal bearings as hip resurfacing components for treatment in young, active patients. This study examines the effects of fixation (cemented or uncemented heads) and bone-implant interface conditions (stem-bone and head-bone) on the biomechanics of the Birmingham hip resurfacing (BHR) arthroplasty, using high resolution, 3-d computational models of the bilateral pelvis from a 45-year-old donor. Femoral bone stress and strain in the natural and BHR hips were compared. Bone remodelling stimuli were also determined for the BHR hips using changes in strain energy. Proximal femoral bone stress and strain were non-physiological when the BHR femoral component was fixed to bone. The reduction of strain energy within the femoral head was of sufficient magnitude to invoke early bone resorption. Less reduction of stress was demonstrated when the BHR femoral component was completely debonded from bone. Bone apposition around the distal stem was predicted based on the stress and strain transfer through the stem. Femoral stress or strain patterns were not affected by the type of fixation medium used (cemented vs. Uncemented). Analysis of proximal stress and strain shielding in the BHR arthroplasty provides a plausible mechanism for overall structural weakening due to loss of bony support. It is postulated that the proximal bone resorption and distal bone formation may progress to neck thinning as increasing stress and strain transfer occurs through the stem. This may be further exacerbated by additional proximal bone loss through avascular necrosis. Medium term retrieval specimens have shown bone remodelling that is consistent with our results. It is unclear if the clinical consequences of neck thinning will become more evident in longer-term follow-ups of the BHR

Aims. We investigated whether blood metal ion levels could effectively identify patients with bilateral Birmingham Hip Resurfacing (BHR) implants who have adverse reactions to metal debris (ARMD). Patients and Methods. Metal ion levels in whole blood were measured in 185 patients with bilateral BHRs. Patients were divided into those with ARMD who either had undergone a revision for ARMD or had ARMD on imaging (n = 30), and those without ARMD (n = 155). Receiver operating characteristic analysis was used to determine the optimal thresholds of blood metal ion levels for identifying patients with ARMD. Results. The maximum level of cobalt or chromium ions in the blood was the parameter which produced the highest area under the curve (91.0%). The optimal threshold for distinguishing between patients with and without ARMD was 5.5 µg/l (83.3% sensitivity, 88.4% specificity, 58.1% positive and 96.5% negative predictive values). Similar results were obtained in a subgroup of 111 patients who all underwent cross-sectional imaging. Between 3.2% and 4.3% of patients with ARMD were missed if United Kingdom (7 µg/l) and United States (10 µg/l) authority thresholds were used respectively, compared with 2.7% if our implant specific threshold was used, though these differences did not reach statistical significance (p ≥ 0.248). Conclusion. Patients with bilateral BHRs who have blood metal ion levels below our implant specific threshold were at low-risk of having ARMD. Cite this article: Bone Joint J 2016;98-B:1455–62

Surface replacement arthroplasty (SRA) has been proposed as a viable option for the treatment of osteoarthritis in young, active patients. Positive results of the Birmingham Hip Resurfacing (BHR) in select patient groups have been described in international series and registry data. We report 5–10 year U.S. follow-up for the BHR at our high volume institution. 314 patients (361 hips) between 2006–2011 underwent BHR at our institution and agreed to participate in research. Demographic features, modified Harris Hip Score, UCLA Activity Score, and satisfaction were recorded for patients with minimum 5-year follow-up (90%). Radiographs were evaluated for implant position and “at risk” signs. Complications, reoperations, and revisions were investigated. Mean modified Harris Hip and UCLA scores significantly improved postoperatively to scores of 89.96 and 7.90 (p < 0.001), respectively. Kaplan-Meier estimated survival for all-cause revision was 96.7% [95% CI 94.7 – 98.7%] at 5 years and 91.5% [95% CI 85.3 – 97.6%] at 10 years. Estimated survival for aseptic revision in males less than 60 years old with a primary diagnosis of osteoarthritis was 99.5% [95% CI 98.7 – 100%] at 5 years and 98.8% [95% CI 97.0 – 100%] at 10 years. 14 patients required revision, including 5 revisions for adverse local tissue reaction. Our study demonstrated excellent survivorship and clinical outcomes at 5–10 year follow up for the BHR. These results mirror other series and registry data published outside of the United States. Continued long-term follow-up and additional studies are necessary to validate the long-term safety and outcomes of the BHR, especially in young active arthroplasty patients

The Birmingham reSurfacing Arthroplasty (BSA) is a metal on metal prosthesis with no published independent clinical studies. Despite this, it is increasing in popularity, especially as an alternative to stemmed prostheses in younger patients. This study presents the 1year migration results of the BSA femoral component using Roentgen Stereophotogrammteric Analysis (RSA). Twenty six subjects underwent a BSA, through the postero-lateral approach using CMW3G cement, with RSA marker balls placed intra-operatively. The femoral component migration was measured at intervals of 3, 6 and 12 months using the Oxford RSA system. Geometric algorhythms were used to identify the femoral component. The data was examined for distribution prior to analysis. All statistical analysis was performed using the t-test. The data was normally distributed. The 1 year migration results of the BSA femoral component are displayed below. All cemented implants migrate in vivo. The majority of cemented stemmed implant migration occurs within the first post-operative year. High rates of migration within the first post-operative year correlate with premature component failure in some instances. The BSA is a fundamentally different design to most cemented prostheses, despite this we know that very large migrations, those in excess of 2mm/year in any direction are generally regarded as poor indicators of long term outcome. These results suggest that the BSA femoral component is an inherently stable device as it does not migrate significantly within the first post-operative year. Only long-term independent clinical studies and continued RSA follow-up will enable a comprehensive evaluation of the device

We undertook this study to determine whether the concerns regarding early complications following hip resurfacing were justified. One hundred and twenty-nine consecutive resurfacing procedures (118 patients, mean age 52.3 years) utilising the Birmingham hip prosthesis were reviewed at a mean of 36.1 (range 24–62) months. Pre-operative diagnosis included osteoarthritis (94), Dysplasia (19), AVN (8), Inflammatory arthropathy (8). Immediate post-operative x-rays were analysed for prosthesis placement and interface gaps. Follow up films were assessed for lucent lines, osteolysis, bone resorption and component migration. Harris hip and UCLA activity scores were recorded pre and post operatively on all patients. Three patients were lost to follow up. Five cases were revised. Three cases due to femoral neck fracture. One patient developed late infection and subsequently fractured. All four patients underwent successful revision to an uncemented stem. One patient required revision of the acetabular component due to migration following a fall three years postop. Five cases of osteolysis were seen (Acetabulum (3), Femur (2)). Four cases of bone resorption at the femoral neck were noted. Two patients developed significant heterotopic ossification (Brooker II & III). All patients with radiological abnormalities were asymptomatic. The mean Harris hip score pre-operatively was 56.4 increasing to 97.5 post-operatively. The mean UCLA activity score pre-operatively was 3.3 increasing to 7.4 post-operatively. Kaplan-Meier survivorship was 94.7% at 5 years. Surface replacement gives excellent clinical results and offers significant advantages over conventional hip replacement. Long-term results are awaited to fully evaluate the effects of resurfacing arthroplasty

We report the survival at ten years of 173 consecutive Birmingham Hip Resurfacing’s implanted between August 1997 and August 1998 at a single institution. Failure was defined as revision of either the acetabular or femoral component for any reason during the study period. The survival at the end of ten years was 96.5% (95%c. i. 89.1 – 99.5%) The mean age of the patients at implantation was 50 years (range 15 – 75). There were 124 (72%) male cases and 49 (28%) female cases. 123 (71%) cases had the diagnosis of osteoarthritis, 9 osteonecrosis, 5 rheumatoid and 3 DDH. The posterior approach was used in 154 (89%) cases and anterolateral in 19 (11%). Cases were performed by 5 different surgeons. There were 5 revisions, 9 unrelated deaths and 18 were lost to follow-up beyond 5 years. Two revisions occurred for infection (6 months and 2 years). A revision at 3.5 years for acetabular loosening and two further at 6.4 and 7.9 years due to avascular necrosis of the femoral head and collapse were performed. No other revisions are impending. The median pre-operative oxford hip score was 61% (IQR 48–73) and the median 10 year score was 7% (IQR 0–31) for 110 completed forms. Further analysis of the total resurfacing database at this institution of 2775 cases was performed. Cox-proportional hazard analysis identified that component size and pre-operative diagnosis were significantly associated with failure. Although females may initially appear to have a greater risk of revision this is related to differences in the size and pre-operative diagnosis between the genders. This study confirms that hip resurfacing using a metal-on-metal bearing of known provenance can provide a solution in the medium term for the younger more active adult who requires surgical intervention for hip disease

Maintenance of the bone stock is a primary goal in hip surgery. The idea of a resurfacing hip prosthesis had already been proposed in the past without success. The improvement in prosthetic materials, however, has mades it possible to reconsider the use of resurfacing prostheses. We report our experience with the Birmingham hip resurfacing (BHR) prosthesis. We operated on 58 patients (60 hips, two bilaterally), 31 men, 27 women, with a mean age of 47.9 years (25–76) and a mean follow-up of 27 months (1–42). We used the posterolateral approach with the patient in lateral decubitus. We performed a clinical and radiographic examination before surgery and at 1 and 6 months postoperatively. We recorded a statistically significant improvement in the clinical score at 6 months after surgery, with respect to the preoperative examination. Major complications were two fractures of the femoral neck and one infection. We recorded also peri-prosthetic calcifications in two patients, calcifications of the ileopsoas in two and ileopsoas tendinitis in one. In conclusion, in our experience, the BHR prosthesis reproduced the biomechanics of the hip and minimised the risk of luxation. The preliminary clinical results are encouraging, also for difficult cases

Introduction: The Birmingham Hip Resurfacing (BHR) device was introduced in 1997 as a conservative hip arthroplasty option for young patients with severe arthritis. Primary osteoarthritis is the most common etiology of hip arthritis in the West. Excellent early and medium-term results have been reported with the BHR. This is a 9–year review of the first 100 consecutive BHRs performed by one surgeon (DJWM) for primary OA. Methods: The first 100 BHRs (91 patients) performed for OA are now at a mean follow-up of 9.1 (range 8.9 to 9.3) years. Four patients (5 hips) died 5.2 to 6.9 years later due to unrelated causes. Patients with unrevised hips were reviewed clinico-radiologically and with questionnaire assessment. Results: With revision for any reason as the end-point there were four failures (two were post-operative AVN leading to femoral head collapse, 8 months and 7 years after their respective operations; and two were deep infections both 5 years after operation). Kaplan-Meier survival analysis showed a 96% cumulative survival at 9 years (figure). There were no failures from osteolysis or aseptic loosening and no patient is awaiting a revision for any reason. Discussion: The performance of the BHR continues to be good at 9 years. Arthroplasty devices are known to manifest two phases of failure, one in the early years and another in the later years. Early failure with this device has been very low. The interim years are continuing to be promising and we are yet to find out when the late failures, if any, are likely to occur

Introduction: The results of Birmingham Hip Resurfacing (BHR) device in several series reveal that the predominant mode of failure is femoral neck fracture or femoral head collapse and that careful patient selection and precise operative technique are vital to the success of this procedure. In this report we consider the results of BHR in patients with severe arthritis secondary to femoral head AVN. Methods: This is a single-surgeon consecutive series of BHRs with a minimum follow-up of 5 years. Fifty six patients with Ficat-Arlet grade III or IV femoral head AVN and treated with BHRs at a mean age of 44.2 years (range 19 to 67.7 years) were followed-up for 5 to 9.2 years (mean 6.8 years). No patient died and none was lost to follow-up. Revision for any reason was the end-point and unrevised patients were assessed with Oxford hip scores. They were also reviewed clinically and with AP and lateral radiographs. Results: There were four failures in this cohort giving a failure rate of 7% and a cumulative survivorship of 92.9% at 9 years (figure). In one further patient the femoral component has tilted into varus from further collapse of the femoral head. He is asymptomatic but knows that he will need a revision if he develops symptoms. No other patient shows clinical or radiological adverse signs. Discussion: Several studies have shown that the results of arthroplasty are generally worse in AVN as compared to those in osteoarthritis. Reviewing the above results it appears to us that the relatively poorer cumulative survival observed in patients with a diagnosis of AVN (92.9%) compared to those with other diagnoses make AVN a relative contraindication to this procedure

Introduction. The results of the Birmingham Hip Resurfacing (BHR) device in several series reveal that the predominant mode of failure is femoral neck fracture or femoral head collapse and that careful patient selection and precise operative technique are vital to the success of this procedure. In this report we consider the results of BHR in patients with severe arthritis secondary to femoral head AVN. Methods. This was a single-surgeon consecutive series of BHRs with a minimum follow-up of 5 years. Fifty-nine patients with Ficat-Arlet grade III or IV femoral head AVN (66 hips) and treated with BHRs at a mean age of 43.9 years (range 19 to 67.7 years) were followed up for 5.4 to 9.6 years (mean 7.1 years). No patient died and none was lost to follow-up. Revision for any reason was the end-point and unrevised patients were assessed with Oxford hip scores. They were also reviewed clinically and with AP and lateral radiographs. Results. There were five failures in this cohort, giving a failure rate of 7.6% and a cumulative survivorship of 86% at 9.6 years. In one further patient the femoral component has tilted into varus from further collapse of the femoral head. He is asymptomatic but knows that he will need a revision if he develops symptoms. No other patient shows clinical or radiological adverse signs. Discussion. Several studies have shown that the results of arthroplasty are generally worse in AVN as compared to those in osteoarthritis. Reviewing the above results it appears to us that the relatively poorer cumulative survival observed in patients with a diagnosis of AVN (86%) compared to those with other diagnoses make AVN a relative contraindication to the hip resurfacing procedure

The Birmingham Hip Mid Head Resection (BMHR) was designed to accommodate patients with lower quality bone in the proximal half of the femoral head. It is a relatively new conservative hip implant with promising early results. Finite element modelling may provide an insight into mid-term results. A cadaveric femur was CT scanned and 3D geometry of the intact femur constructed. The correctly sized BMHR implants (with and without visual stop) were positioned and these verified by a surgeon; hence constructing the post-operative models. Walking loads were applied and contact surfaces defined. Stress analyses were performed using the finite element method and contact examined. Also, a strain-adaptive bone remodelling analysis was run using 45% gait hip loading data. Virtual DEXA images were computed and were analysed in seven regions of the bone surrounding the implants. The BMHR was found to be mechanically stable with all surfaces indicating micromotion less than the critical 150 microns. Stress distribution was similar to the intact femur, with the exception of the head-neck region where some stress/strain shielding occurs. This is mirrored in the bone remodelling results, which show some bone resorption in this region. The visual stop, which is designed to ensure that the stem is not overdriven during implantation, did not affect the stress/strain results; only on a very local scale. There is minimal data available in the literature regarding conservative hip implants and no data regarding the BMHR. This study is the first to look at the mechanical response of the bone to this implant

Introduction. Since the introduction of 3rd generation Metal-on-Metal-Hip-Resurfacing-Arthroplasty (MoMHRA), thousands of such prostheses have been implanted worldwide in younger patients with end-stage hip osteoarthritis. However, no independent centre has reported their medium-to-long term outcome. The aim of this study is to report the ten year survival and outcome of the Birmingham Hip Resurfacing (BHR), the most commonly used MoMHRA worldwide. Methods. Since 1999, 648 BHRs were implanted in 555 patients, the majority of which were male (326). The mean age at surgery was 52.1years (range: 17–82), with primary OA as most common indication (85%). Mean follow up was 7.1years (range: 1–11). The Oxford Hip Score (OHS) and UCLA questionnaires were sent to all patients. Implant survival was established, with revision as the end point. Sub-analysis was performed by gender, femoral component size (small: <45mm, standard: 46–52, large: >53mm) and age at surgery (young:<50yrs, old:>50yrs). Results. Preliminary results show that survival and clinical outcome were better in men than women (p=0.013) and in patients with large and standard components compared to small (p=0.005). In women the survival and clinical outcome were worse in the young than the old (p=0.049). In men there was no difference in survival or clinical outcome between the young and old (p=0.106). In young men the 10-year survival was 95%, the mean OHS was 45 and the mean UCLA score was 8.1. Conclusion. The results of resurfacing are good in men. They perform particularly well in the young and highly active men who tend to have problems with conventional hip replacements

Introduction: The incidence of younger people requiring arthroplasty is on the rise. Metal on metal Hybrid hip resurfacing arthroplasty is an exciting alternative to conventional arthroplasty, to Orthopaedic surgeons, in young active patients where preserving bone stock is important. Materials and Methods: All patients with a hybrid Birmingham hip resurfacing arthroplasty (cemented femoral component and a hydroxyappitie coated press fit acetabulum) from 1997–2001, operated by the senior surgeon were followed up. They had annual AP and lateral x-rays, the pre and post op Harris hip scores were recorded and a patient satisfaction survey was done. Results: There were 36 patients, aver follow up 17.2 months, the aver age was 52.Except for 2 patients with femoral neck fractures which required revision there were no other significant complications. Both these patients had a notched femoral neck intraoperatively. There were no revisions for aseptic loosening .The average preop and post op Harris hip scores were 45.5 and 92.1 respectively. There were no radiological signs of loosening. 93% said they would recommend it to others, 93 % rated the surgery as being excellent to good and 96 % returned to normal or near normal level of activity as. Conclusions: We feel that Conservative Hip arthroplasty with resurfacing of the femoral head is an attractive concept particularly in younger patients. The advantages are preservation of bone stock, non violation of the proximal femur, reduction of stress shielding in the proximal femur and it is quite physiological. The one important thing is to avoid notching the neck to prevent disastrous fractures. The implant is less forgiving and the learning curve is steep. The ultimate usefulness can only be gauged once longer follow-ups are available

Introduction: The Birmingham Hip Resurfacing (BHR) is a metal on metal prosthesis with no published independent clinical studies. It is increasingly used as an alternative to stemmed prostheses in younger patients. This study presents the 2 year migration results of the BHR femoral component using Roentgen Stereophoto-grammteric Analysis (RSA). Methods: 26 hips in 24 subjects underwent a BHR, through the postero-lateral approach using CMW3G cement. RSA marker balls were placed in the cortical bone of the femur intra-operatively. The femoral component migration was measured at intervals of 3, 6, 12 and 24 months postoperatively using the Oxford RSA system. The implants were un-modified, geometric algorithms were used to identify the femoral component. Results: The BHR femoral component showed no significant displacement from its immediate post-operative position. All components of migration showed no significant displacement in any direction, at 1 or 2 years. Conclusion: The BHR femoral component does not migrate significantly within the first two post-operative years. Its’ migration compares favourably to other designs of femoral component. The BHR is therefore likely to remain stable in the future, as the majority of implant migration occurs within the first two years

Conversion of failed femoral components of total hip resurfacing to conventional hip replacement is reportedly a straightforward procedure. There is little published to qualify this and what is available suffers from small study numbers and various combinations pre and post-operative implants. Between 1997 and 2002, the Oswestry Outcome Centre prospectively collected data on 5000 Birmingham Hip Resurfacings (BHRs) performed by 141 surgeons, at 87 hospitals. To date 4526 have survived, 135 died and 165 are lost to follow-up. 174 have been revised, of which 60 were failures of the femoral component. We reviewed modes of failure and post-revision clinical outcomes in this sub-group. Isolated femoral component failure accounted for 60 hips (1.2%). 28 femoral neck fractures, 14 femoral head collapses, 13 femoral component loosenings, 3 avascular necroses (AVN), 1 femoral loosening followed by fracture and 1 dislocation. Mean time to revision surgery was 2.6 years (1.8 years for neck fracture; 3.4 years femoral loosening, head collapse and AVN). All acetabular components were left in situ. At revision surgery 25 cemented, 25 uncemented and 10 unknown femoral prostheses were used with 56 BHR modular heads, 2 custom-made Exeter heads and 2 Thrust Plate heads. 47 patients completed outcome scores post-revision surgery. Median modified Harris Hip Score was 82 (IQ range=63–93) and Merle d’Aubigne score was 14 (IQ= 9.5–15) at a mean follow up of 3.9 years post-revision. The 4526 surviving resurfacings had a median hip score of 96 (IQ=87–100) p≤4.558x10-8 and median Merle score of 17 (IQ=14–18) p≤1.827x10-7. Mean 7.0 years follow up. There was no difference in outcomes between cemented and un-cemented revision components nor were there differences between fractured neck of femur and femoral loosening, head collapse or AVN. Following revision of the femoral component to a conventional hip replacement, function is significantly worse than surviving resurfacings

We report the long-term survival and functional outcome of the Birmingham Hip Resurfacing (BHR) in patients aged < 50 years at operation, and explore the factors affecting survival. Between 1997 and 2006, a total of 447 BHRs were implanted in 393 patients (mean age 41.5 years (14.9 to 49.9)) by one designing surgeon. The mean follow-up was 10.1 years (5.2 to 14.7), with no loss to follow-up. In all, 16 hips (3.6%) in 15 patients were revised, giving an overall cumulative survival of 96.3% (95% confidence interval (CI) 93.7 to 98.3) at ten years and 94.1% (95% CI 84.9 to 97.3) at 14 years. Using aseptic revision as the endpoint, the survival for men with primary osteoarthritis (n = 195) was 100% (95% CI 100 to 100) at both ten years and 14 years, and in women with primary osteoarthritis (n = 109) it was 96.1% (95% CI 90.1 to 99.9) at ten years and 91.2% (95% CI 68.6 to 98.7) at 14 years. Female gender (p = 0.047) and decreasing femoral head size (p = 0.044) were significantly associated with an increased risk of revision. The median Oxford hip score (OHS, modified as a percentage with 100% indicating worst outcome) at last follow-up was 4.2% (46 of 48; interquartile range (IQR) 0% to 24%) and the median University of California, Los Angeles (UCLA) score was 6.0 (IQR 5 to 8). Men had significantly better OHS (p = 0.02) and UCLA scores (p = 0.01) than women. The BHR provides excellent survival and functional results in men into the second decade, with good results achieved in appropriately selected women. Cite this article: Bone Joint J 2013;95-B:1172–7

Introduction: Conversion of failed femoral components of total hip resurfacing to conventional hip replacement is reportedly a straightforward procedure. There is little published to qualify this and what is available suffers from small study numbers and various combinations pre and post-operative implants. Method: Between 1997 and 2002, the Oswestry Outcome Centre prospectively collected data on 5000 Birmingham Hip Resurfacings (BHRs) performed by 141 surgeons, at 87 hospitals. To date 4526 have survived, 135 died and 165 are lost to follow-up. 174 have been revised, of which 60 were failures of the femoral component. We reviewed modes of failure and post-revision clinical outcomes in this sub-group. Results: Isolated femoral component failure accounted for 60 hips (1.2%). 28 femoral neck fractures, 14 femoral head collapses, 13 femoral component loosenings, 3 avascular necroses (AVN), 1 femoral loosening followed by fracture and 1 dislocation. Mean time to revision surgery was 2.6years (1.8years for neck fracture; 3.4years femoral loosening, head collapse and AVN). All acetabular components were left in situ. At revision surgery 25 cemented, 25 uncemented and 10 unknown femoral prostheses were used with 56 BHR modular heads, 2 custom-made Exeter heads and 2 Thrust Plate heads. 47 patients completed outcome scores post-revision surgery. Median modified Harris Hip Score was 82 (IQ range=63–93) and Merle d’Aubigne score was 14 (IQ= 9.5–15) at a mean follow up of 3.9years post-revision. The 4526 surviving resurfacings had a median hip score of 96 (IQ=87–100) p≥4.558x10-8 and median Merle score of 17 (IQ=14–18) p≥1.827x10-7. Mean 7.0 years follow up. There was no difference in outcomes between cemented and uncemented revision components nor were there differences between fractured neck of femur and femoral loosening, head collapse or AVN. Discussion: Following revision of the femoral component to a conventional hip replacement, function is significantly worse than surviving resurfacings

Introduction: Interest in hip resurfacing has recently been renewed by the introduction of metal-on-metal designs; it is being increasingly used for young patients, with over 30,000 implanted worldwide. The 5 year clinical results appear promising, but there are no long term data available. Radiostereometry (RSA) measures of implant migration have been able to predict implant failure; specifically large and continuous migration predicts aseptic loosening. We present the results of a five year RSA study examining the migration of the Birmingham Hip Resurfacing (BHR). Methods: Twenty-four subjects with primary OA were implanted with the BHR device and with bone markers for RSA. RSA measurements were taken at 3, 6, 12, 24 and 60 months. The migration of the head and the tip of femoral component were measured in 3D. Results: Preliminary analysis showed that the total 3D migration of the head and tip over five years was 0.32mm and 0.23mm respectively. Discussion: A distal migration of more than 0.4mm over 2 years increases the likelihood of failure in conventional stems. The total migration of the BHR was approximately 0.3mm over a five year period, significantly less than cemented THR devices. The device is stable and this is promising for long-term survival

Approximately 46,000 total hip replacements are performed in the U.K. annually with a dislocation rate between 2 and 5%. Birmingham hip resurfacing (BHR) is a bone conserving metal on metal prosthesis, designed for young patients with hip arthroses that claims to substantially reduce the problem of dislocation. Derek McMinn has reported a personal series of 1,030 BHR’s with a dislocation rate of 0.001% (1 out of 1,030). We present a consecutive series of 55 BHR’s performed by one consultant between January 1998 and June 2001 with a dislocation rate of 7.3% (4 out of 55). 3 out of 4 dislocations occurred in anatomically abnormal hips (two occurred in a patient with developmental dysplasia of the hips and one with avascular necrosis of the femoral head). In this paper, we discuss the possible causes of dislocation in BHR. We suggest careful patient selection by less experienced surgeons to reduce the risk of dislocation following BHR

Introduction: There has been a renewed interest in metal-on-metal bearing for total hip replacement with the benefit of a larger head size and decreased incidence of dislocation. In the revision hip scenario cementation of a polyethylene liner, for a previously compromised liner fixation mechanism into a preexisting well-fixed shell or a cage, has become an accepted method to decrease the morbidity of the procedure. Perhaps Bir-mingham cementless cups could be used as cemented devices in primary and revision hip surgery where a cementless cup is not possible. Aim: To study the pull-out strength of cemented Bir-mingham sockets in an experimental model. Materials and Methods: Eight Birmingham cups were cemented into wooden blocks after they were reamed to the appropriate size allowing for a 3mm cement mantle, multiple holes drilled into the reamed sockets and cement vacuum-mixed. Cable was then threaded through the holes on the rim of the cup and the wooden block was then mounted on a metal plate and secured. Linear tension was then gradually applied on the cup through the cable. Results: The pull-out strength of the cemented Birming-ham cups was higher than the failure of the cable. The tensile load to failure for the cables ranged from 3642.6 N to 4960 N with an average load of 4286.9 N. Conclusion: The average tensile load of 4286.9 is very high compared to previous studies with cemented poly-ethylene and metal liners. This finding is very promising and might support clinical application in complex primary and revision total hip replacement

Introduction: Hip resurfacing is a renaissance of metal on metal hip arthroplasty. It preserves bone stock and a large head allows greater range of motion. This new technique is gaining popularity among patients and surgeons alike. We present a nine year follow up in the context of survival, function and complications. Methods: We analysed follow up data of 4778 patients who have had hip resurfacing using Birmingham Hip resurfacing (Smith & Nephew, UK) in 37 countries. Patients were followed up annually using Oswestry hip score and any revisions were updated on the database at the Oswestry Outcome Centre. Function was analysed using multilevel modelling and Kaplan-Meier method used for survival analysis. Results: There were 3193 males and 1585 females operated by 138 surgeons in 37 countries. The mean age was 52.8 years (13 – 87.8). Using hierarchical regression the annual hip scores were analysed. Overall function was significantly affected by pre op score and gender (p< 0.01). Age at operation had no effect on outcome score (p =.462). We observed similar effect in individual domains of pain, mobility and range of motion. Survival of the implant at nine years with revision due to any reason was 93.5%. We observed a significant difference in survival of procedures done by pioneer surgeons and by non pioneering surgeons (p < 0.01) (log rank test). There were 119 complications of which there were 30 fractures, 21 occurring within the first six months of operation. Conclusion: Nine year results of hip resurfacing arthroplasty look promising and are comparable to traditional hip arthroplasty. The difference between two surgeon groups could be due to a learning curve in the technique. Further follow up would be necessary to ascertain the long-term clinical effectiveness of this technique

Introduction: The Birmingham Hip Resurfacing(BHR) has shown encouraging early to medium term results. It has tended to be used in patients wishing to achieve high functional activity. However there is little data available to support this notion. The purpose of the study was to report the functional levels of patients following BHR. Methods: Since February 2000, 313 patients have undergone resurfacing by the senior author. Two hundred and sixty four patients with a minimum 12 month follow-up were assessed for functional activity using the modified UCLA activity score. Patients were asked to score their activity level during the pre-symptomatic period as well as pre-operatively and during follow-up. Results: The mean age at surgery was 55.7 years. The mean follow-up period was 46.72 months. The revision rate for any reason was 3.8%. The mean pre-symptomatic, pre-operative, one year post-operative and final follow-up UCLA scores were 7.9, 3.7, 6.6 and 7.0 respectively. At one year 89% (235 patients) had improved by at least one activity grade from pre-operative levels and 35% (93 Patients) achieved functional scores the same as, or better than their pre-symptomatic levels. This increased to 45% at final follow-up. Of the 242 patients previously involved in moderate activity(UCLA> =5), 31% regained this activity level at one year, rising to 40% at last follow-up. Only 19% of the 180 patients participating in very active/impact sports(UCLA> =8) obtained these levels at one year, rising to 30% at last follow-up. Conclusion: This is the first assessment of function after BHR comparing pre-symptomatic scores with those obtained during follow-up. Functional scores continue to improve beyond one year in all groups. Significant numbers of patients can achieve functional levels at least as good as before they developed symptoms from their hip, however, the proportion of patients achieving this goal reduces with increasing pre-symptomatic activity

The Birmingham mid-head hip resurfacing arthroplasty (Smith & Nephew, Tennessee) (BMHR) is designed for use in patients with avascular necrosis of the femoral head. The BMHR has limited short-mid term follow-up results. We report the experience of 27 consecutive BMHR procedures with a minimum two year follow-up. 23 patients (20 males and 3 females) with an average operation age of 49.8 years (SD ±10.9) (22–65) were investigated. The mean follow-up period was 3.0 years (SD ±0.77). The operations were between April 2008 and November 2011 by one surgeon. Data and outcome measurements were collected prospectively and analysed retrospectively. Procedures were reviewed to determine function. We evaluated Harris Hip Scores, Short Form-36 (SF-36v2) Scores, Tegner Activity Score Scores and McMaster Universities Osteoarthritis Index Scores (WOMAC) comparatively at preoperative, six month and yearly intervals. Paired samples t-tests were applied to determine improvements where p<0.05 was deemed as significant. There were no patient deaths. There were no revisions. Harris Hip scores for pre-operative 6, 12, 24 and 36 month intervals were: 52.30, 84.14, 83.07, 87.50 and 89.50. Average pre-operative 6, 12, 24 and 36 month SF36v2 Total scores were: 116.54, 124.32, 130.44, 135.97 and 133.18. Tegner scores for pre-operative 2.75, 3.29, 3.00, 3.67 and 3.01. WOMAC Total scores for aforementioned intervals for the posterior approach were: 59.51, 84.22, 90.30, 86.86 and 92.25. The mean Harris Hip scores improved significantly between preoperative and 6, 12, 24 and 36 months (p<0.001). The mean SF-36v2 physical scores improved significantly between preoperative and 6, 12, 24 and 36 months (p<0.016). WOMAC scores improved significantly between preoperative and 6, 12, 24 and 36 months (p<0.017). The presence of avascular necrosis significantly increases the revision rate for hip resurfacing surgery. The BMHR prosthesis, in this short term follow-up, appears to avoid the main cause of failure, femoral component loosening. Longer term efficacy remains to be seen. We plan to continue close supervision of these patients

We report the survival, functional and radiological outcome of a series of Birmingham hip resurfacing procedures performed by a single surgeon at a district general hospital. The aim of this study was to retrospectively report the medium term outcome and survival of our patients. There were 45 hip resurfacings performed in 38 patients between 2004 and 2010. Patients were followed for a mean duration of four years. Mean age of 52.6 years (range 26 to 65). Although no patients were lost to follow up, four did not complete the oxford hip scoring assessment. The median Oxford hip score was 16.25 points (range 12–39 points, standard deviation 5.9) at 48 months follow up (range 11.5–84.2 months). The mean acetabular inclination was 46.9 (range 40.9–59.9) in the 45 hip resurfacings post operatively. There was one patient with varus subsidence of the prosthesis and one patient with persistent hip pain post operatively under investigation currently. There was no definite radiological evidence of loosening or of narrowing of the femoral neck. No cases were revised and no cases developed any other complications. These medium-term results from a district general hospital are comparable to the other studies performed. Few independent studies have reported the outcome of resurfacing arthroplasty of the hip in a district general hospital. Further evaluation and follow up of these patients is required to address the concerns raised by other centers related to fracture and metal debris

This study reports the early results of Birmingham Hip Resurfacing in a group of patients less than 25 years of age. We assessed over a period of 5 years all patients who underwent hip resurfacing who were under the age of 25. Thirty-eight patients underwent 43 hip resurfacing procedures for a variety of diagnoses. This included 15 with Developmental Dysplasia of the Hip (DDH), 13 with Osteonecrosis (ON) of the femoral head, and 7 with End-stage Spastic Hip Disease (ESSHD). We assessed complications, failure and revision rates. Patients completed co-op and oxford hip scores and both clinical and radiographic assessments. At a follow-up of a maximum of 5 years the survival rate was 93% with a further 7% showing radiographic features of failure. Thirteen hips (30%) had a femoral osteotomy at the time of resurfacing allowing correction of length and rotation with no apparent increase in complications. Those who required revision were successfully converted to metal- metal total hip replacement. Our results report the first use of this type of prosthesis in a group of patients under the age of 25 and demonstrate comparable results to standard treatments at this early stage. This study supports the use of hip resurfacing as alternative to conventional treatments for this complex group of patients

Aim: Hip resurfacing is a bone conserving procedure with respect to proximal femoral resection. For previous generations of conservative hip replacement, preservation of the natural femoral head diameter necessitated additional sacrifice of acetabular bone in order to accommodate a sufficiently thick polyethylene acetabular component. We have investigated whether the BHR offers a bone conserving procedure with respect to the acetabular bone stock. Method: We reviewed 284 Birmingham resurfacing hip replacements (BHR), and 479, primary hip replacements, in which an uncemented acetabular component (THUA) was used. The BHR and THUA group had mean age at surgery of 55 and 65 years respectively. In 32 BHR’s and 21 THUA, pre-operative templating measurements were available for subsequent comparison with size of component implanted. Results: Comparison of component sizes, for both implant types, confirmed bi-modal distribution according to patient gender. BHR cups, implanted by the first author, in females, were significantly smaller than those implanted, by the same author, in THUA,(p< 0.0001). Pre-operative templating overestimated component size for all groups but the difference was only significant in male BHR cases;(p=0.03). BHR cups implanted by the first author were significantly smaller than the second author, for both male (p= 0.0001) and female patients;(p< 0.001). Conclusion: In females, BHR is bone a conserving procedure for femoral and acetabular components. In males, the procedure is not bone sacrificing when compared to THUA. Pre-operative templating can overestimate size of acetabular component that will be used for men. A significant difference was found between size of acetabular components used by two surgeons for BHR

Introduction. Secondary osteoarthritis in a dysplastic hip is a surgical challenge. Severe leg length discrepancies and torsional deformities add to the problem of inadequate bony support available for the socket. Furthermore, many of these patients are young and wish to remain active, thereby jeopardising the long-term survival of any arthroplasty device. For such severely dysplastic hips, the Birmingham Hip Resurfacing (BHR) device provides the option of a dysplasia component, a hydroxyapatite-coated porous uncemented socket with two lugs to engage neutralisation screws for supplementary fixation into the solid bone of the ilium more medially. The gap between the superolateral surface of the socket component and the false acetabulum is filled with impacted bone graft. Methods and results. One hundred and thirteen consecutive dysplasia BHRs performed by the senior author (DJWM) for the treatment of severely arthritic hips with Crowe grade II and III dysplasia between 1997 and 2000 have been reviewed at a minimum five year follow-up. There were 106 patients (59M and 47F). Eighty of the 113 hips were old CDH or DDH, 29 were destructive primary or secondary arthritis with wandering acetabulae and four were old fracture dislocations of the hip. Mean age at operation was 47.5 years (range 21 to 68 years – thirty-six men and forty-four women were below the age of 55 years). There were two failures (1.8%) out of the 113 hips at a mean follow-up of 6.5 years (range 5 to 8.3 years). One hip failed with a femoral neck fracture nine days after the operation and another failed due to deep infection at 3.3 years. Conclusion. The dysplasia resurfacing device offers a good conservative arthroplasty option for these severely deficient hips

A review of the first two hundred and ten patients undergoing Birmingham hip re-surfacing between January 2003 and June 2005 was performed. All surgeries were performed by a single consultant orthopaedic surgeon. All resurfacings were carried out utilising the antero-lateral approach to the hip. Mean review post-operatively was at six weeks. The following clinical parameters were evaluated: length of in-hospital patient stay, intra-operative blood loss and post-operative range of joint movement. In addition, the following radiological measurements were made: the acetabular inclination angle, the head-shaft angle and evidence of leg-length discrepancy. One patient experienced fracture of the femoral neck and two other patients underwent revision surgery. Our results demonstrate that the anterolateral approach represents an alternative approach, with short-term results comaprible to the posterior approach for hip resurfacing

Introduction: We aimed to examine the effect of neck notching during hip resurfacing on the strength of the proximal femur. Methods: Third generation composite femurs that have been shown to replicate the biomechanical properties of human bone were utilised. Imageless computer navigation was used to position the initial guide wire during head preparation. Six specimens were prepared without a superior notch being made in the neck of the femur, six were prepared in an inferiorly translated position to cause a 2mm notch in the superior femoral neck and six were prepared with a 5mm notch. All specimens had radiographs taken to ensure that the stem shaft angle was kept constant. The specimens were then loaded to failure in the axial direction with an Instron mechanical tester. A three dimensional femoral finite element model was constructed and molded with a femoral component constructed from the dimensions of a Birmingham Hip Resurfacing. The model was created with a superior femoral neck notch of increasing depths. Results: The 2mm notched group (mean load to failure 4034N) were significantly weaker than the un-notched group (mean load to failure 5302N) when tested to failure (p=0.017). The 5mm notched group (mean load to failure 3121N) were also significantly weaker than the un-notched group (p=0.0003) and the 2mm notched group (p=0.046). All fractures initiated at the superior aspect of the neck, at the component bone interface. The finite element model revealed increasing Von Mises stresses with increasing notch depth. Discussion: A superior notch of 2mm in the femoral neck weakens the proximal femur by 24% and a 5mm notch weakens it by 41%. This study provides biomechanical evidence that notching of the femoral neck may lead to an increased risk of femoral neck fracture following hip resurfacing due to increasing stresses in the region of the notch

Abstract: resurfacing hip arthroplasty has shown promising early results in the treatment of hip arthrosis in younger patients as published from specialist centres in the United Kingdom. We are reporting early results and complications of Birmingham hip resurfacing arthroplasty (BHR) from a district general hospital. This is a retrospective study of 216 hips in 186 patients during January 1999 to December 2004. The study included review of notes and X rays and a questionnaire based assessment of hip function and activities using Oxford Hip Score (OHS) and Duke’s activity score (DAS). This study has got national ethical committee approval. The response rate for questionnaire was 76%. Average age was 53.3 years (range 20–72). Male: female ratio was 3:1. There were 152 unilateral and 32 bilateral cases. Majority of the cases had osteoarthritis in the hip. Average follow-up was 30.3 months (range 12–72). Average length of stay was 6 days (range 3–17). Average OHS and DAS were 15.8 and 51 respectively. 163 patients had OHS of less than 24. 113 patients had DAS of 58.2. Radiological assessment showed six cases of hetero-topic calcification. Lysis was noted at prosthesis-neck junction in two cases but patients were asymptomatic. The complications included superficial wound infection in 2, DVT in 6, neuroparaxia of sciatic and brachial plexus in one case each. There were six dislocations. There were nine revisions – seven following fracture neck of femur and two for aseptic loosening. The incidence of fracture neck of the femur was high in early part of the study suggesting technical improvement with experience. Overall failure was 4.1%, slightly higher than other published literature. The OHS and DAS were comparable to other published results. In conclusion the results of the BHR are encouraging and long-term prospective study is needed to find out the longevity of the implants and long-term results

Introduction: Recently, high-flexion knee implants have been developed to provide for a large range of motion (ROM > 120°) after total knee arthroplasty (TKA). High-flexion knee implants are more likely subjected to large knee loads than conventional implants since knee joint forces increase with larger flexion angles. Highly conforming knee replacements are designed to minimise polyethylene peak stresses during (deep) knee flexion. The Birmingham Knee Replacement (BKR, Jointmedica, UK) is a newly designed knee replacement which combines a high conformity during the complete ROM with the principles of rotating platform and high-flexion TKA. The main objective of this study was to analyze the mechanical performance of the BKR during its full ROM (0°–155°) and investigate whether its high conformity could be maintained during high-flexion. In addition, the BKR polyethylene loading computed in this study was compared with other mobile bearings. Materials & methods: TKA performance was analyzed using a three-dimensional dynamic finite element (FE) model of the knee joint. The FE knee model consisted of a distal femur, a proximal tibia and fibula, a quadriceps and patella tendon, a non-resurfaced patella and TKA components. Tibio-femoral and patello-femoral contact were defined in the knee model. Three different posterior stabilised rotating platform TKAs were subsequently incorporated: the high-flexion BKR, the high-flexion PFC Sigma RP-F and the standard PFC Sigma RP (Depuy, J& J, USA). The polyethylene insert was modelled as a non-linear elastic-plastic material in each TKA system. Polyethylene loading parameters as well as the tibio-femoral contact point locations were computed during an entire flexion movement (0°–155°). Results: In the normal flexion range (flexion ≤ 120°) the three knee implants behaved very similar except for the polyethylene loading at the post. At 120° of flexion, the contact stress at the dish was ±45 MPa for all implants whereas the maximal post-cam contact stress came down to 26.7 MPa for the BKR which was half the amount of contact stress experienced by both PFC Sigma implants. During high-flexion (flexion > 120°), the contact stress difference at the post between the BKR and the PFC Sigma RP-F became smaller and came down to 37.9 MPa and 60.7 MPa, respectively. The total amount of plastic deformation at maximal flexion (155°) was smaller for the BKR (577 mm3) in comparison with the Sigma RP-F (2256 mm3). Femoral rollback was negligible for the BKR in the high-flexion range in comparison with the Sigma RP-F (1.9 mm). Discussion: A comparison between different geometrical models using finite element techniques is jeopardised by differences in element distribution within the various models. These differences may affect calculated parameters such as peak stress values. However, in this study the models were very similar which would indicate that the differences in stress patterns found are due to design differences rather than model artefacts. The current study therefore indicates that the BKR benefits from its high conformity during the full ROM. Hence, the BKR demonstrated relatively low polyethylene stresses. The quadriceps efficiency during deep knee flexion may be lower in case of the BKR since the femoral rollback was negligible at these flexion angles. Whether this phenomenon is of any clinical relevance is unknown

Metal-metal hip resurfacing offers the advantage of conservation of femoral bone stock. In addition, the implant may offer enhanced resistance to dislocation in comparison with conventional total hip arthroplasty. We present a series of 32 female patients with one to 4 year follow up (mean age 57 ranges 50–70 at time of surgery). All patients required hip arthroplasty. Careful preoperative selection was carried out with particular attention paid to estimation of bone density. A standard resurfacing operation was carried out. Patients had pre and postoperative WOMAC and SF36 scoring. All patients were followed closely in the post operative period. No significant complications were noted at follow up. In our study we have shown that given careful patient selection Birmingham hip resurfacing can be safe and reliable form of arthroplasty

Birmingham Metal-on-metal total hip resurfacing (BHR) is a bone-conserving option for patients with advanced articular damage. While the outcomes of Total Hip Replacement (THR) are well documented, there is a paucity of literature comparing the patient reported outcomes of BHR versus THR. This study aims to compare the patient reported outcomes for an impact on quality of life between patients who had a BHR vs. THR after correcting for selection bias. Patients who underwent a BHR or THR between July 2003 and December 2006 were included. Patient questionnaires included demographic details, co-morbidities, WOMAC, SF-36 Scores. In addition, a 4 point Likert scale was used to measure satisfaction post-operatively. The above data was collected pre-operatively and at 1, 2, 3 and 5 years post-operatively. Data was analysed with SPSS (version 19) software package. All analysis was adjusted for Age, gender, Co-morbidity and pre-operative score by using Multivariate regression analysis using a General Liner Model to rule out the effect of these predictors on outcomes between groups. 337 patients were included (205 for THR and 132 for BHR). BHR patients were younger than THR patients (49 vs. 67 years, p<0.01), were more likely to be male (68% vs. 42% of THR, p<0.01), reported fewer co-morbidities (1.06 vs. 1.59, p<0.01). BHR patients reported better WOMAC pain and function scores at 5 years (p<0.05). For SF-36 scores, BHR patients reported higher scores for all 8 domains at 1 year and 5 year follow up (p<0.05). BHR patients reported higher satisfaction than THR group for return to Activities of Daily Living and Recreational activities at 1 and 5 years (p<0.05). After correction for patient variability, BHR patients reported better improvement in pain and function and enjoyed a better quality of life in relation to return to ADL and recreational activities over to 5 years post-surgery

We describe our early experience with the implantation of the first consecutive 231 primary Birmingham Hip resurfacings. At a mean follow up of 33 months, survivorship was 99.14 %, with revision in one patient for a loose acetabular component and one unrelated death. Mean Harris Hip score improved from a mean of 62.54 ( Range : 8–92) to 97.74. (Range: 61 – 100) Mean flexion improved from a mean of 91.52°, ( Range : 25° –140°) to a mean 110.41°. ( Range : 80° – 145°). 1 patient presented at 6 weeks post resurfacing with pain and no history of trauma. An undisplaced fracture of the superior femoral neck was seen, which healed with a period of non-weight bearing. 96.94% of patients rated their prosthesis as good / excellent, the remainder rated it good/fair

Introduction: While the explant device has made revision of uncemented acetabular components technically easier, the unique design of the Birmingham Hip Resurfacing(BHR) acetabular component precludes the use of the standard explant extractor. The dual radius geometry of this socket causes impingement and damage to the curved blade of this device. A novel adaptor was designed to correct for the differential radii and enable removal of the well fixed BHR socket with the explant. We present the results of our initial experience with this device. Method: A prospective study was performed to evaluate the effectiveness of this device for revising the well fixed BHR socket. All cases were performed by a single surgeon via a posterior approach. The explant cup extractor was used with its standard centering head and curved blades. The size of the explanted cup, last reamer size and size of the implanted component were recorded. Results: Three males and 7 females were included. Their average age was 58.1 years (48–65). Average time to revision of the BHR sockets was 24.2 months (7–40). Average explanted cup size was 51mm (46–58) and final reamer size 53.8mm (51–59). Average final socket size was54.8 (50–62). Overall there was a mean 2.8.mm size difference between the explanted cup and the final reamer. Discussion: The thickness of the blade of the explant was 2mm therefore only 0.8 mm of bone was lost on average. The device enables a simple reproducible removal of the well fixed BHR sockets with preservation of acetabular bone stock

Introduction: The need to meet the demands for a hip replacement that will allow young patients to maintain a high activity level with the expectation of enhanced longevity has been the Holy Grail of modern orthopaedic practice for some time. Novel bearing surfaces and methods of component fixation have not as yet managed to sate this need. The Birmingham Hip Resurfacing (BHR) offers a number of theoretical advantages for this demanding patient group. The metal on metal bearing couple facilitates fluid film lubrication and thus minimises wear and reduces osteolysis. The large head size enhances stability minimising the risk of dislocation during strenuous activity. Resurfacing anatomically restores hip geometry facilitating normal hip biomechanics. Finally, in the event of failure preservation of bone stock makes revision surgery less challenging. In the absence of long-term outcome studies for the BHR these advantages remain theoretical. Furthermore, reports of good short and medium term results require corroboration at independent centres. This paper presents early results in a large series of patients in such an independent unit. Patients and Methods: Between March 1999 and December 2001, 102 patients were deemed suitable for hip resurfacing. Patients were felt to be suitable if they were active, had no comorbid conditions that might compromise bone quality and were sixty five years old, although this was not an absolute figure. Pre-operative work up was performed to exclude generalised disease that might compromise bone quality, including bone density measurement where appropriate. Baseline Harris hip scores were performed preoperatively and at latest follow up. Operative details were recorded along with per-operative and other complications. Patients were followed up clinically and radiologically at an average of 13 months (range 3–30 months). Results: There were 86 male and 16 female patients with an average age of 47 (range 28–66) for the men and 48 (range 21–55) for the women. Five patients had acetabular dysplasia as a primary diagnosis, four had AVN, one had post-traumatic arthritis and the remainder had primary osteoarthritis. There were no patients with inflammatory arthritis or severe dysplasia. Average Harris hip score pre-operatively was 52 (range 25–65). This had improved to 89 at latest follow-up. All operations were performed via an extended posterior approach. No patients had neuro-vascular complications. Average hospital stay was 6.5 days; average transfusion requirement was 0.3 units. There were two spontaneous femoral neck fractures, both presenting with pain at approximately 2 months. Both were revised to conventionally stemmed femoral components with large metal heads (Corin. TM. ). One patient presented with pain at 8 months and X-rays showed a fractured neck of femur. At revision, pus was found and diagnosis of infection was assumed. It was treated with a one-stage revision. 93 patients said they were very satisfied with their outcome and two were moderately satisfied. All patients who were more than six months post op (67 patients) had returned to their previous work (41 office work, 16 retailing, 10 farming). Twenty-six patients had returned to active leisure pursuits including running, golf, horse-riding and tennis. Discussion: When considering new advances in arthroplasty, long-term outcome studies are necessary before any firm conclusion can be drawn regarding ultimate efficacy. This study, however, confirms that BHR is safe and gives good short-term results. While there is no substitute for long-term studies, we feel that these early results are encouraging and justify continued work with the procedure in the context of a critical prospective study

Background: High volumetric wear of polyethylene was the main factor in periprosthetic bone resorption and the failure of historic metal or ceramic on polyethylene hip resurfacing prosthesis. Metal on metal devices reduce the wear substantially and may solve this problem. The present study describes the clinical and radiographic results of our first 300 hips treated with the Birmingham Hip Resurfacing (BHR, Midland Medical Technologies, U.K.). Methods: Between September 1998 and May 2003, 300 BHR were implanted in 262 patients. The patients had an average age of 49 years, 56% were men, 58% had a diagnosis of a CDH, 19% of osteoarthritis and 11% of avascular necrosis. Clinical and radiographic follow-up was performed at three months postoperatively and yearly thereafter. Results: The average duration of follow-up was 2.4 years (1 to 5 years). We achieved a follow-up rate of 97%. Mean Harris Hip Score increased from 51 points pre-operatively to 91–92 points after one to five years, Total range of motion increased from 136 to 220. 6 prostheses had to be revised due to malposition (2), infection (2), neck fracture (1) and inguinal pain (1). Acetabular radiolucencies were observed in 3% in one zone, femoral radiolucencies in 5% in one to three zones around the stem. No patient showed radiolucency lines in all zones or migration. Conclusions: In our opinion the cementless press fit cup, the low wear metal-on-metal bearing and the conservative implantation technique of the BHR at least fundamentally improves the known disadvantages of the historic Resurfacings. Our preliminary experience is encouraging, but has to be proofed in long-term observations

Introduction: Metal on metal hip resurfacing is a bone conserving procedure with excellent medium term results. A retrospective audit of 150 consecutive Birmingham Hip resurfacings, performed by a single surgeon at a DGH was carried out. Materials and Methods: We report 150 hip resurfacings implanted between June 2001 to June 2004. There were 99 male and 51 female hips. The mean age was 50.7 years (38–75years). Range of follow up was 6 months to 45 months (average 20.1 months). Pre operative diagnosis was Osteoarthritis (n=135), osteonecrosis(n=8),traumatic(n=2),dysplasia(n=3),Slipped capital femoral epiphysis (n=1) and ankylosing spondylitis (n=1). Al hips were implanted via the posterior approach. Clinical assessment, by postal questionnaire, was by pre and post-operative Oxford Hip scores (OHS) and X-rays were reviewed. Results: Range of follow up was 6 months to 42 months (average 20.1 months). No patient was lost to follow up. The mean pre operative Oxford hip score was 41 (r=27–56). The score was 15.1 (r=12–29) at the time of questionnaire. Complications included: One femoral neck fracture at 3 months requiring revision to a stemmed “big ball” THR, one deep infection requiring early wash out with salvage of the hip prosthesis, (both the patients are now doing well. OHS 13 and 15 respectively) and one asymptomatic stress fracture of femoral neck, which healed without intervention (OHS 12). There was one dislocation in a neuropathic hip requiring bracing. (OHS 29). There was one retained alignment pin needing removal. Otherwise patients were highly satisfied with the operation with excellent function and Hip scores. Conclusion: Our study has demonstrated that, in the short term and in young age group, this prosthesis gives excellent functional results, with an acceptably low complication rate. Long term surveillance of these patients will provide further data to compare our results with specialist centres

Introduction: We compared the eight- to ten-year clinical and radiological results of the metal-on-metal Birmingham hip resurfacing (BHR) with a hybrid total hip arthroplasty (HYBRID) in two groups of 54 hips, previously matched for gender, age, body mass index and activity level. Method: Patients were followed up in outpatients and function assessed by using the Oxford Hip Score, UCLA activity score and Euroqol score. Radiographs were assessed for osteolysis and wear. BHR were also assessed for the presence of a pedestal sign around the femoral component. Results: The mean follow up of the BHR group was 9 years (8.17 to 10.33) and for hybrids 10 (7.53 to 14.5). Four patients had died in the hybrid group and one in the BHR. Four were lost to follow up in each group. The revision rate in the BHR group was 9.25% verses 18% in the Hybrid, a further eight patients in the hybrid group have evidence of wear and osteolysis and are intended for revision (p=0.008). One patient in the BHR group was explored for late onset sciatic nerve palsy. All patients in the hybrid group had evidence of polyethylene wear, mean 1.24mm (0.06–3.03). 90% of the BHR group had evidence of a pedestal sign. Satisfactory function was shown in both groups. There was no significant difference between groups with respect to the OHS but the UCLA score was superior in the BHR group (p=0.008). There was no significant difference for Euroqol visual analogue score. 56% of hybrids were delighted with their hip replacement verses 65% of BHR patients. Discussion: After ten years the hip resurfacing patients were still more active and had a lower revision burden than the hybrid hip replacements. Both groups showed worrying radiological evidence of change with long-term follow-up

Introduction: As candidates for arthroplasty become younger and life expectancy increases the required working life of a total hip arthroplasty continues to rise. Hip resurfacing offers potential further advantages in young patients as minimal bone resection makes for easier revision, and the design allows for an increased range of movement. The Birmingham Hip Resurfacing (BHR) is the first of the second generation hip resurfacings. Reports are beginning to emerge of unexplained failure, pseudotumour formation, individual cases of metallosis. Joint registry data also demonstrates an unexplained high early failure rate for all designs of hip resurfacing. This paper examines the rate and mode of early failures of the BHR in a multi-centre, multi-surgeon series. Methods: All patients undergoing BHRs in our two centres were recruited prospectively into our arthroplasty follow up programme. Patients have been followed up radiographically and with clinical scores. Results: Mean radiographic and clinical follow up was to 43 months (range 6 – 90 months). Of the 463 BHRs two have died and three are lost to follow up. Thirteen arthroplasties (2.8%) have been revised. Eight for pain, three for fracture, two for dislocation and one for sepsis. Of these nine were found to have macroscopic and histological evidence of metalloisis. Survival analysis at 5 years is 95.8% (CI 94.1 – 96.8%) for revisions and 96.9% (CI 95.5 – 98.3%) for metallosis. Discussion: Histopathological examination demonstrated a range of inflammatory changes including necrosis, inflammation, ALVAL and metal containing macrophages. Not all features were associated with each patient and it is likely that these features form part of the spectrum of metal wear debris disease. The likely rate of metallosis is 3.1% at five years. Risk factors for metallosis in this series are female sex, small femoral component, high abduction angle and obesity. We not advocate use of the BHR in patients with these risk factors

Introduction. Hip resurfacing (HRA) designer centres have reported survivorships between 88.5–96% at 12 years. Arthroplasty Registries (AR) reported less favourable results especially in females gender and small sizes. The aim of this study was to evaluate the minimum 10-year survival and outcome of the Birmingham Hip Resurfacing (BHR) from an independent specialist centre. Methods. Since 1998, 1967 BHRs have been implanted in our centre by a single hip resurfacing specialist. The first 249 BHR, implanted between 1999 and 2001 in 232 patients (17 bilateral) were included in this study. The majority of the patients were male (163; 69%). The mean age at surgery was 50.6 years (range: 17–76), with primary OA as most common indication (201; 81%), followed by avascular necrosis (23; 9.2%) and hip dysplasia (11; 4.4%). Mean follow up was 10.2 years (range: 0.1 (revision) to 13.1). Implant survival was established with revision as the end point. Harris Hip Scores (HHS), radiographs and metal ion levels were assessed in all patients. Sub-analysis was performed by gender, diagnosis and femoral component size (Small: <50 mm; Large: ≥50 mm). Results. Of the 232 patients, 15 were deceased (4 bilateral BHR), 16 lost to follow-up and 9 revised. 205 BHR were evaluated at minimum 10 years postoperatively. Failure modes included 2 component malpositioning, 2 loose femoral heads, 1 fracture, 1 metal sensitivity, 2 impingement and 1 with high metal ions. The overall survival was 95.1% (95% CI: 93.6–96.6) at 12.8 years. The mean HHS was 97.8 (range: 65–100). Survivorship in men was 98.6% (95%CI: 97.4–99.8%) at 13 years. Survivorship in women was inferior to men (log rank = 0.003): 87.9% (95%CI: 84.3–91.5%) at 12 years. There was no difference in HHS between genders in the non-revised cases (p = 0.46). There was no difference in survivorship with different pre-operative diagnosis (log-rank = 0.83) but a significant difference in 12-year survivorship between Small (90.1%) and Large components (97.2%) (log rank = 0.01). After adjusting for head size, the difference in survival between males and females was no longer significant (log-rank = 0.125). The median ion levels were Cr:2.0μg/l; Co:1.0μg/l. In 24 patients the ion levels were undetectable. Four patients (1.9%) had ions above the upper acceptable limits of Cr:4.6μg/l;Co:4.0μg/l for unilateral or Cr:7.4μg/l;Co:5.0μg/l for bilateral HRA. In 67 patients with consecutive ion measurements, levels decreased significantly with time with a mean decrease of 0.97μg/l for Cr and 0.60μg/l for Co. Discussion. This study reports the more than 10-year survival of BHR and reflects an experienced specialist's practice, including his learning curve of the procedure. The overall 12.8-year survival was superior to registry reported figures of THA amongst young patients and corresponded well with reports from designer centres. Survivorship and clinical outcome were excellent in men. In women survivorship was significantly inferior and related to smaller component sizes, but the >10-year clinical outcome in non-revised cases was excellent. In well-functioning BHR, the metal ions decrease significantly with time. The results of this study support the use of HRA with a good design

Hip resurfacing arthroplasty is emerging as an increasingly popular, conservative option for the treatment of end-stage osteoarthritis in the young and active patient. Despite the encouraging clinical results of hip resurfacing, aseptic loosening and femoral neck fracture remains concerns for the success of this procedure. This study used finite element analysis (FEA) to analyse the stresses within proximal femoral bone resulting from implantation with a conservative hip prosthesis. FEA is a computational method used to analyse the performance of real-world structures through the development of simplified computational models using essential features. The aim of this study was to examine the correlation between the orientation of the femoral component of a hip resurfacing prosthesis (using the Birmingham Hip Resurfacing as a model) and outcomes during both walking and stair climbing. The outcomes of interest were stresses in the femoral neck predisposing to fracture, and bone remodelling within the proximal femur. Multiple three-dimensional finite element models of a resurfaced femur were generated, with stem-shaft angles representing anatomic (135°), valgus (145°), and varus (125°) angulations. Applied loading conditions included normal walking and stair climbing. Bone remodelling was assessed in both the medial and lateral cortices. Analyses revealed that amongst all orientations, valgus positioning produced the most physiological stress patterns within these regions, thereby encouraging bone growth. Stress concentration was observed in cortical and cancellous bone regions adjacent to the rim of the prosthesis. As one would expect, stair climbing produced consistently higher stress than walking. The highest stress values occurred in the varus-orientated femur during both walking and stair climbing, whilst anatomic angulation resulted in the lowest stress values of all implanted femurs in comparison to the intact femur. This study has shown through the use of FEA that optimising the stem-shaft angle towards a valgus orientation is recommended when implanting a hip resurfacing arthroplasty. This positioning produces physiological stress patterns within the proximal femur that are conducive to bone growth, thus reducing the risk of femoral neck fracture associated with conservative hip arthroplasty

Introduction: The Trent arthroplasty register reported that results of Hip arthroplasty in general setup were less than that reported from specialist centres by 5%. This independent prospective study tests the hypothesis that results of Birmingham Hip Resurfacing arthroplasty from specialist centres would not accurately represent the outcome of hip resurfacing when performed in general setup. Material and Methods: All patients were prospectively followed for at least five years at Oswestry Hip outcome centre. The surgeons carrying out the operation prospectively provided surgical details and thereafter patients were followed using Oswestry hip questionnaire (OSHIP) at fixed intervals. Survival was assessed by Kaplan-Meier method. The results were compared to the published results of BHR from specialist centers. Results: There were 679 patients, and 58 surgeons in the study. Mean age at operation was 51 years and mean follow up was 5.63 years. The predominant preoperative diagnosis was osteoarthritis. The mean OSHIP score was 89.5. There were 29 (4.2%) failures mostly due to fracture neck of femur (62%); all of them were revised to conventional THR. The Kaplan-Meier survival at seven years is 95.354%. Discussion: Compared to the published results, there were 2 to 19 times high failure rate which is significantly higher (p=0.001) than the published studies. Hence we prove our hypothesis, as the results of BHR from specialist centres do not accurately reflect on the outcome in general setup. The discrepancy in the results that we have identified would help to identify the weak areas in the general setup, where most of the patients get benefited from BHR arthroplasty

Background: This study was undertaken to investigate the differences in the metal ion serum concentrations after implantation of a MetaSUL-THR and a Birmingham Hip Resurfacing in comparison to implant free subjects and to review the influence of factors, possibly influencing the wear behaviour of the articulation. Methods: Serum levels of cobalt, chromium and molybdenum in 74 patients after primary implantation of a MetaSUL-THR and in 111 patients after BHR were compared with the levels found in 130 control subjects without implants. Serum ion concentration was determined by atomic absorption spectrophotometry. Furthermore, the correlation between serum ion concentration and in-situ time, implant size and cup inclination was studied. Results: The chromium and cobalt concentrations of BHR-patients as well as the chromium concentration of bilateral MetaSUL-THR-patients, however, were significantly higher as the concentrations of patients with unilateral MetaSUL-THR and the control group. The molybdenum serum concentration was very similar in all investigated groups. The chromium serum concentration in patients with unilateral MetaSUL-THR and in patients with BHR showed the highest level in the postoperative period from 7 to 12 months. Analyses of the subgroups showed an association between higher cobalt serum levels and cup inclination greater than 50 in patients with unilateral MetaSUL-THR more than 12 months after implantation. A statistically significant negative correlation was detectable between implant size and chromium as well as cobalt serum concentration in BHR-patients studied more than 12 months after implantation. Conclusions: Metal-on-metal bearings of large diameter result in a greater systemic exposure of cobalt, chromium and molybdenum ions than bearings of smaller diameter. It is not known to what extent the different levels are due to corrosion of the surfaces of the components or to the amount of wear particles produced. The chromium concentrations were highest 7–12 months after operation, what may due to a running-in of the bearing like known from hip simulator studies. Interestingly implant size and metal ion serum levels correlate negatively in the BHR-patients studied more than 12 months after implantation. That could be due to an existing fluid film lubrication in these bearings and may be caused by the thicker fluid film in bearings with greater radius

Hip resurfacing has been proposed as an alternative to traditional total hip arthroplasty in young, active patients. Much has been learned following the introduction of metal-on-metal resurfacing devices in the 1990s. The triad of a well-designed device, implanted accurately, in the correct patient has never been more critical than with these implants.

Following Food and Drug Administration approval in 2006, we studied the safety and effectiveness of one hip resurfacing device (Birmingham Hip Resurfacing) at our hospital in a large, single-surgeon series. We report our early to mid–term results in 1333 cases followed for a mean of 4.3 years (2 to 5.7) using a prospective, observational registry. The mean patient age was 53.1 years (12 to 84); 70% were male and 91% had osteoarthritis. Complications were few, including no dislocations, no femoral component loosening, two femoral neck fractures (0.15%), one socket loosening (0.08%), three deep infections (0.23%), and three cases of metallosis (0.23%). There were no destructive pseudotumours.

Overall survivorship at up to 5.7 years was 99.2%. Aseptic survivorship in males under the age of 50 was 100%. We believe this is the largest United States series of a single surgeon using a single resurfacing system.

Cite this article: Bone Joint J 2016;98-B (1 Suppl A):10–13.

Purpose: We report a series of 117 consecutive metal-on-metal Birmingham Hip Resurfacings in 105 patients with a minimum of 5 year follow up. Method: Patients were followed up both clinically and radiographically for a minimum of 5 years following implantation. Revision of either the femoral or acetabular component during the study period is defined as failure. Results: We followed up 114 of 117 hips (97%). We had 4 failures giving us survivorship at 5 years of 97% (95% confidence interval (CI) 94–100). The mean follow up was 72 months and the mean age at implantation 54.5 years old. The mean Oxford Hip Score fell from 41.6 preoperatively to 15.3 postoperatively (p< 0.0001). The mean Harris Hip Score at 5 year follow up was 96.4. The UCLA Activity Scale rose from 3.93 preoperatively to 7.54 postoperatively (p< 0.001). Radiographic analysis revealed neck thinning in 12 patients (10%) and we define a method of measuring this. The average stem shaft angle in our cohort was 130 degrees and the average cup angle was 36 degrees. Heterotropic ossification was present in 17 hips (15%). Conclusion: This study confirms that metal-on-metal resurfacing produces an excellent clinical and functional outcome in the younger patient who requires surgical intervention for hip disease. The results compare favourably with those from the originating centre and confirm that resurfacing is well suited for younger higher demand patients. It is the first study with a minimum 5 year follow up outside the originating centre