Background. Using one-stage bilateral free vascularized fibular grafting (FVFG) to treat avascular necrosis of the femoral head (ANFH) remains controversy due to potential high-risk and technical complexity. The purpose of the present study was to evaluate the safety and effectiveness of one-stage bilateral FVFG procedure versus unilateral FVFG in the treatment of ANFH. Methods. One-stage bilateral FVFG was performed for 26 patients with bilateral ANFH between March 2001 and September 2006. The clinical and radiographic outcomes, hospital stays, and postoperative complications in this group were compared with those from another 33 patients (40 hips) receiving unilateral FVFG. Results. The two groups had similar hospital stays, clinical outcome, and few complications. In an average follow-up of 36 months, one major and five minor complications were encountered in the onestage bilateral group, and one major and three minor complications in the unilateral group. The mean Harris hip scores increased from 63.8±16.795%CI: 61.266.4 to 84.2±1795% CI: 81.586.9 points in the unilateral group and from 61.7±22.295%CI: 58.664.8 to 82.0±16.6 95%CI:79.784.3 points in the one-stage bilateral group. In radiographic, there was no obvious difference in progression of collapse between the two groups. Conversion to hip arthroplasty was performed in 2 (5%) hips in the unilateral group and none in the one-stage bilateral group, with no statistically significant difference between the two groups. Conclusion. Using one-stage bilateral FVFG to treat ANFH is a safe and effective method with minor postoperative morbidity

Aims

Despite limited clinical scientific backing, an additional trochanteric stabilizing plate (TSP) has been advocated when treating unstable trochanteric fractures with a sliding hip screw (SHS). We aimed to explore whether the TSP would result in less post operative fracture motion, compared to SHS alone.

Introduction. Femorotibial malalignment exceeding ±3° is a recognised contributor of early mechanical failure after total knee replacement (TKR). The angle between the mechanical and anatomical axes of the femur remains the best guide to restore alignment. We investigated where the femoral head lies relative to the pelvis and how its position varies with respect to recognised demographic and anatomic parameters. We have tested the hypothesis of the senior author that the position of the centre of the femoral head varies very little, and if its location can be identified, it could serve to outline the mechanical axis of the femur without the need for sophisticated imaging. Patients & Methods. The anteroposterior standing, plain pelvic radiographs of 150 patients with unilateral total hip replacements were retrospectively reviewed. All patients had Tönnis grade 0 or 1 arthritis on the non-operated hip joint. All radiographs were obtained according to a standardised protocol. Using the known diameter of the prosthetic head for calibration, the perpendicular distance from the centre of the femoral head of the non-operated hip to the centre of pubic symphysis was measured with use of TraumaCad software. Anatomic parameters, including, but not limited to, the diameter of the intact femoral head, were also measured. Demographic data (gender, age, height, weight) were retrieved from our database. Results. There were 72 men and 78 women with a mean age of 67.0 years. The mean distance of the centre of the femoral head to the pubic symphysis was 89.1 mm (standard deviation [SD], 5.8 mm). This distance was higher in men (mean, 90.5 mm; SD, 5.6 mm) than in women (mean, 87.7 mm; SD, 5.8 mm) (p=0.003). No statistically significant correlations between this distance and body-mass index or age (p=0.57 and p=0.28, respectively) were revealed. However, height was strongly correlated with this distance (r=0.52, p < 0.01), as was the diameter of the femoral head (r=0.61, p < 0.01). The latter was significantly larger in men than in women (p < 0.01). Conclusion. This is the first study to demonstrate that the position of the centre of the femoral head has very little variability, irrespective of patient age or body-mass index. As expected, it varies with patient's height and gender. Although statistically significant, the difference between genders is < 3 mm and can be explained by the smaller femoral head size of females. Our findings should prove useful during TKR surgery, as they facilitate intra-operative identification of the centre of the femoral head. Based on these results, simple trigonometry shows that if a surgeon measures 9 cm from the symphysis pubis, a line from this point to the centre of the knee will be within 2° and 2.2° of the true mechanical axis in 98% (i.e. ± 3 SD of the mean) of male and female patients, respectively

Introduction. The objective of this study was to determine if a synthetic bone substitute would provide results similar to bone from osteoporotic femoral heads during in vitro testing with orthopaedic implants. If the synthetic material could produce results similar to those of the osteoporotic bone, it could reduce or eliminate the need for testing of implants on bone. Methods. Pushout studies were performed with the dynamic hip screw (DHS) and the DHS Blade in both cadaveric femoral heads and artificial bone substitutes in the form of polyurethane foam blocks of different density. The pushout studies were performed as a means of comparing the force displacement curves produced by each implant within each material. Results. The results demonstrated that test material with a density of 0.16 g/cm. 3. (block A) produced qualitatively similar force displacement curves for the DHS and qualitatively and quantitatively similar force displacement curves for the DHS Blade, whereas the test material with a density of 0.08 g/cm. 3. (block B) did not produce results that were predictive of those recorded within the osteoporotic cadaveric femoral heads. Conclusion. This study demonstrates that synthetic material with a density of 0.16 g/cm. 3. can provide a good substitute for cadaveric osteoporotic femoral heads in the testing of implants. However we do recognise that no synthetic material can be considered as a definitive substitute for bone, therefore studies performed with artificial bone substrates may need to be validated by further testing with a small bone sample in order to produce conclusive results

Introduction. Metal-on-metal hip resurfacing (MOMHR) is a good surgical indication for young active patients. However, it cannot be used in patients with an excessively short femoral head/neck. To address these cases, a new surgical technique has been developed comprising femoral head augmentation using impacted morcellized bone grafts. Methods. 32 osteoarthritis patients who had severe congenital insufficiency of the femoral head/neck were treated with MOMHR combined with femoral head augmentation. Mean patient age was 49 ± 9 years (18–66). The required amount of augmentation was calculated on preoperative X-rays and confirmed during surgery. Using specially designed instrumentation, bone chips produced while reaming the socket and trimming the head were impacted onto the head to achieve the desired reconstruction and lengthening. Finally, the femoral component was cemented. Results. Mean head lengthening was 12 ± 2mm. Mean follow-up was 4.2 years (3–6). Mean preoperative Harris hip score was 58, increasing to 95 at follow-up (p<0.05). Mean leg lengthening was 2.2cm (p=0.001). In all Gruen zones, bone mineral density (BMD) decreased during the first 3 months. At 2 years, in zone 1, mean BMD increased to 96.8% (p=0.009) and to 102.1% in zone 7 (p=0.05). A correlation was found between valgus positioning of the femoral components and increased BMD (p=0.005). To date, only 1 patient has been revised due to socket loosening. Discussion and conclusions. This bone grafting technique expands the use of MOMHR to patients with severe deficiencies of the femoral head, thereby leading to a more anatomical reconstruction with a full recovery of function and BMD of the proximal femur

We have carried out a prospective study of 17 patients (14 women, 3 men) of mean age 48 years (21 to 76) with transcervical fractures of the femur using MRI to detect early evidence of avascular necrosis of the head. Two fractures were Garden stage I, 12 stage II, and three stage III. We performed internal fixation under radiological control at a mean of five days (2 to 15) after injury using a titanium cannulated cancellous screw or a titanium compression hip screw. MRI was performed at one, six and 12 months and then yearly after operation. T1- and T2-weighted images were obtained by a spin-echo technique. The duration of follow-up of patients who did not subsequently require replacement of the head of the femur was from 2 to 5 years (mean 3.2). One month after operation eight of the 17 hips showed a band of low signal intensity on T1-weighted images and high signal intensity on T2-weighted images indicating lesions in the femoral head away from the fracture line. These were of three types: type I was a small infarct at the superolateral region of the femoral head and was seen in three hips; type II was a shallow lesion from the superolateral region to the fovea of the femoral head (three hips); and type III was a large lesion occupying most of the femoral head (two hips). No further changes were seen in the MRI after six months from operation. Collapse of the femoral head did not occur in the three hips with type-I lesions, but two of the three type-II hips and both type-III hips subsequently collapsed. At the final follow-up the three hips with a type-I lesion and one with a type-II were still asymptomatic but radiography showed sclerosis in the femoral head corresponding to the MRI lesions. The nine hips which showed no changes on MRI at one month had no abnormal findings on physical examination, radiography or MRI at final follow-up

The prevalent cause of implant failure after total joint replacement is aseptic loosening caused by wear debris. Improvement of the wear behaviour of the articulating bearing between the cup and femoral head is essential for increased survival rate of artificial hip joints. Cross-linking of the polyethylene (PE) material is one attempt to reduce wear particle release at the articulating surface. Various cross-linked polyethylenes (X-PE) are used in orthopaedics since several years. In total hip arthroplasty (THA) the use of larger femoral head sizes has specific reasons. Larger heads lead to a decreased risk of total hip dislocation and impingement as well as an improved range of motion in comparison to smaller head sizes like 28mm or less. However, the increasing diameter of femoral head can be associated with lower thickness of the PE liner and increased wear rate. Cross-linking of PE can improve the wear rate of the liner and hence supports the use of larger femoral heads. The aim of this experimental study was to evaluate the wear of standard vs. sequential X-PE (X3-PE) liner in combination with different ceramic femoral head sizes. Wear testing was performed for 5 million load cycles using standard UHMW-PE liners (N2Vac) and X3-PE liners (each Stryker GmbH & Co. KG, Duisburg, Germany) combined with 28mm ceramic ball heads and the Trident PSL acetabular cup (Stryker). Furthermore, X3-PE liners with an internal diameter of 36mm and 44mm and decreased wall thickness (5.9mm and 3.8mm) were combined with corresponding ceramic heads. An eight station hip wear simulator according to ISO 14242 (EndoLab GmbH, Rosenheim, Germany) was used to carry out the standard wear tests. The tests were realised in temperature-controlled chambers at 37°C containing calf serum (protein content 20g/l). The average gravimetrical wear rates of the standard UHMW-PE (N2Vac) liners combined with 28mm ceramic heads amounted to 12.6 ± 0.8mg/million cycles. Wear of X3-PE liners in combination with 28 mm ceramic heads was not detectable. The average gravimetrical wear rates of the X3-PE liners in combination with 36mm and 44mm ceramic heads amounted to 2.0 ± 0.5mg and 3.1 ± 0.3mg/million cycles, respectively. The purpose of this study was to evaluate the effect of femoral head size at THA on standard and sequential X-PE liner. The wear simulator tests showed that the wear rate of PE liners with small heads (28mm) decreased by cross-linking of the PE significantly. The amount of wear at X-PE increased slightly with larger head size (36mm and 44mm). However, by sequential cross-linking, the wear rate using thinner liners and larger femoral heads is reduced to a fractional amount of wear at conventional UHMW-PE. Hence, the above-mentioned advantages of larger femoral head diameters can be realised by improved wear behaviour of sequential X-PE

Several studies have reported the assessment of the femoral head coverage on plane radiograph and CT data in supine position, though young patients with the dysplastic hip often have symptoms during activities such as standing, walking, and running. On the other hand, some investigators have used a method of CT which allows standardization of the femoral head coverage against an anterior pelvic plane based on the anterior superior iliac spines and the pubic tubercle. We believe both the weight-bearing position and the standardized position to be more relevant for diagnosis and preoperative surgical assessment. So, we show the femoral head coverage in standardized position using 3D-CT method and in weight-bearing position using the plane radiograph and the three-dimensional lower extremity alignment assessment system before and after Curved periacetabular osteotomy (CPO). Especially the covered volume of the femoral head, a new concept, using the three-dimensional lower extremity alignment assessment system which differs from the affected area and is measured by the ratio of the covered area in the medial part of the line connecting the anterior point of the acetabulum with the posterior to the femoral head area in each axial slice, superior slices than the slice passing through the femoral head center, obtained from the reproduced 3D model of the pelvis and the femur in standing position allows us to integrate various measurements reported by past researchers. We studied the consecutive 16 patients treated with CPO. In standardized position the sagittal sectional angles on the slice passing through the femoral head center using 3D-CT method gave us how the anterior, lateral, and posterior coverage was lack compared with normal subjects and whether the adequate transfer of the rotated fragment was performed after operation. The covered volume of the femoral head decides generally the deficiency or the adequateness. In standing position, though the pelvic tilt changes, the femoral head coverage on plane radiograph, representation by the CE angle, the VCA angle, AHI and ARO, was significantly improved, and the covered volume of the femoral head was significantly improved from 25.7% preoperatively to 51.1% postoperatively. Our study showed the improvement of the femoral head coverage, including the covered volume of the femoral head as a new concept, after CPO in weight-bearing and standardized position. The morphological and functional assessment of the femoral head coverage on both pre- and post-CPO should be performed because we can obtain the objective information in standardized position and the femoral head coverage in standing position is closely connected with the pain

Corticosteroid use has been implicated in the development of osteonecrosis of the femoral head (ONFH). The exact mechanism and predisposing factors such as age, gender, dosage, type and combination of steroid treatment remain controversial. Between March and July 2003, a total of 539 patients with severe acute respiratory syndrome (SARS) were treated with five different types of steroid. There were 129 men (24%) and 410 women (76%) with a mean age of 33.7 years (21 to 59). Routine screening was undertaken with radiographs, MRI and/or CT to determine the incidence of ONFH. Of the 129 male patients with SARS, 51 (39.5%) were diagnosed as suffering from ONFH, compared with only 79 of 410 female patients (19.3%). The incidence of ONFH in the patients aged between 20 and 49 years was much higher than that of the group aged between 50 and 59 years (25.9% (127 of 491) versus 6.3% (3 of 48); p = 0.018). The incidence of ONFH in patients receiving one type of steroid was 12.5% (21 of 168), which was much lower than patients receiving two different types (28.6%; 96 of 336) or three different types of steroid (37.1%; 13 of 35). Cite this article: Bone Joint J 2014;96-B:259–62

Introduction and aim. Avascular necrosis (AVN) of femoral head remains a major post-operative complication of the surgical fixation of femoral neck fractures (#NOF). In order to reduce the incidence of AVN following this type of fracture, the National Institute for Clinical Excellence (NICE) has stated that fixation must occur within 6 hours. However, there is a paucity of information concerning whether time to fixation influences the development of AVN. The aim of the present study was to assess whether time to fixation affects the development of AVN in patients aged under 60 who had sustained a fracture (#)NOF. Methods. We looked retrospectively at 101 patients (61 female, 40 male aged under 60 (mean age 47 years) who were admitted to a multi-tertiary centre having sustained an intracapsular #NOF. The underlying co morbidity of the patient sample was varied, as was the mechanism of trauma, though in the majority of cases the cause was a simple fall. The time delay (TD) between the time of injury and the time of operation for each patient was determined. Results. 72 patients sustained an intracapsular displaced fracture and 29 an intracapsular undisplaced fracture. Of these, 33 patients were treated with a dynamic hip screw (DHS), 10 received a DHS plus a cannulated screw, and 54 were treated with cannulated screws only. We looked at time to fixation(TD) as follows: Group A-less than 6 hours (7 patients), Group B-6 to 12 hours (16 patients), Group C-12 to 18 hours (15 patients), Group D-18 to 24 hours (18 patients), Group E −24 to 48 hours (26 patients) and Group F- more than 48 hours(15 patients). Out of 97 patients, 15 (15.46%) developed AVN. Of these, 13 were patients who had sustained an intracapsular displaced fracture, two had sustained an undisplaced fracture. Of the intracapsular displaced fractures patients, the time to fixation varied from 3 hours to 26 hours post-trauma. Of note, twelve of these patients received a cannulated screw and only one was treated with a DHS. The two patients with an undisplaced intracapsular fracture underwent fixation at 13 and 24 hours respectively. The method of fixation was a cannulated screw. Conclusion. Current NICE guidelines state that intracapsular #NOF must be fixed within 6 hours in order to prevent AVN of femoral head. In our sample, 15.46% of patients developed AVN post-fixation. Crucially, 2 patients out of the 7 patients (28.57%) developed AVN despite undergoing fixation within 6 hours. Interestingly, we have observed that fracture fixation with a cannulated screw has a greater propensity to develop AVN despite time to fixation, since 15.46% of patients treated in this manner developed AVN. Taken together, method of fixation rather than time to fixation appears to be a key factor in the incidence of AVN in our patient group

Aims. The aim of this study was to investigate the potentially increased risk of dislocation in patients with neurological disease who sustain a femoral neck fracture, as it is unclear whether they should undergo total hip arthroplasty (THA) or hemiarthroplasty (HA). A secondary aim was to investgate whether dual-mobility components confer a reduced risk of dislocation in these patients. Methods. We undertook a longitudinal cohort study linking the Swedish Hip Arthroplasty Register with the National Patient Register, including patients with a neurological disease presenting with a femoral neck fracture and treated with HA, a conventional THA (cTHA) with femoral head size of ≤ 32 mm, or a dual-mobility component THA (DMC-THA) between 2005 and 2014. The dislocation rate at one- and three-year revision, reoperation, and mortality rates were recorded. Cox multivariate regression models were fitted to calculate adjusted hazard ratios (HRs). Results. A total of 9,638 patients with a neurological disease who also underwent unilateral arthroplasty for a femoral neck fracture were included in the study. The one-year dislocation rate was 3.7% after HA, 8.8% after cTHA < 32 mm), 5.9% after cTHA (= 32 mm), and 2.7% after DMC-THA. A higher risk of dislocation was associated with cTHA (< 32 mm) compared with HA (HR 1.90 (95% confidence interval (CI) 1.26 to 2.86); p = 0.002). There was no difference in the risk of dislocation with DMC-THA (HR 0.68 (95% CI 0.26 to 1.84); p = 0.451) or cTHA (= 32 mm) (HR 1.54 (95% CI 0.94 to 2.51); p = 0.083). There were no differences in the rate of reoperation and revision-free survival between the different types of prosthesis and sizes of femoral head. Conclusion. Patients with a neurological disease who sustain a femoral neck fracture have similar rates of dislocation after undergoing HA or DMC-THA. Most patients with a neurological disease are not eligible for THA and should thus undergo HA, whereas those eligible for THA could benefit from a DMC-THA. Cite this article: Bone Joint J 2022;104-B(1):134–141

Aims

Proximal femur fractures treatment can involve anterograde nailing with a single or double cephalic screw. An undesirable failure for this fixation is screw cut-out. In a single-screw nail, a tip-apex distance (TAD) greater than 25 mm has been associated with an increased risk of cut-out. The aim of the study was to examine the role of TAD as a risk factor in a cephalic double-screw nail.

Aims

Posterior column plating through the single anterior approach reduces the morbidity in acetabular fractures that require stabilization of both the columns. The aim of this study is to assess the effectiveness of posterior column plating through the anterior intrapelvic approach (AIP) in the management of acetabular fractures.

Aims

To assess the feasibility of a randomized controlled trial (RCT) that compares three treatments for acetabular fractures in older patients: surgical fixation, surgical fixation and hip arthroplasty (fix-and-replace), and non-surgical treatment.

Aims. Complex displaced osteoporotic acetabular fractures in the elderly are associated with high levels of morbidity and mortality. Surgical options include either open reduction and internal fixation alone, or combined with total hip arthroplasty (THA). There remains a cohort of severely comorbid patients who are deemed unfit for extensive surgical reconstruction and are treated conservatively. We describe the results of a coned hemipelvis reconstruction and THA inserted via a posterior approach to the hip as the primary treatment for this severely high-risk cohort. Methods. We have prospectively monitored a series of 22 cases (21 patients) with a mean follow-up of 32 months (13 to 59). Results. The mean patient age was 79 years (67 to 87), and the mean ASA score was 3.3 (3 to 5). Three patients had high-energy injuries and 18 had low-energy injuries. All cases were associated fractures (Letournel classification: anterior column posterior hemitransverse, n = 13; associated both column, n = 6; transverse posterior wall, n = 3) with medialization of the femoral head. Mean operative time was 93 minutes (61 to 135). There have been no revisions to date. Of the 21 patients, 20 were full weight-bearing on day 1 postoperatively. Mean length of hospital stay was 12 days (5 to 27). Preoperative mobility status was maintained in 13 patients. At one year, mean Merle d’Aubigné score was 13.1 (10 to 18), mean Oxford Hip Score was 38.5 (24 to 44), mean EuroQol five-dimension five-level (EQ-5D-5L) health score was 68 (30 to 92), and mean EQ-5D-5L index score was 0.68 (0.335 to 0.837); data from 14 patients. Mortality was 9.5% (2/21) at one year. There have been no thromboembolic events, deep infections, or revisions. Conclusion. The coned hemipelvis reconstruction bypasses the fracture, creating an immediately stable construct that allows immediate full weight-bearing. The posterior approach minimizes the operative time and physiological insult in this vulnerable patient population. Early results suggest this to be a safe addition to current surgical options, targeted at the most medically frail elderly patient with a complex displaced acetabular fracture. Cite this article: Bone Joint J 2020;102-B(2):155–161

Aims

To evaluate if, for orthopaedic trainees, additional cadaveric simulation training or standard training alone yields superior radiological and clinical outcomes in patients undergoing dynamic hip screw (DHS) fixation or hemiarthroplasty for hip fracture.

Aims

The aim of this study was to investigate the association between fracture displacement and survivorship of the native hip joint without conversion to a total hip arthroplasty (THA), and to determine predictors for conversion to THA in patients treated nonoperatively for acetabular fractures.

Aims. Our aim in this study was to describe the long-term survival of the native hip joint after open reduction and internal fixation of a displaced fracture of the acetabulum. We also present long-term clinical outcomes and risk factors associated with a poor outcome. Patients and Methods. A total of 285 patients underwent surgery for a displaced acetabular fracture between 1993 and 2005. For the survival analysis 253 were included, there were 197 men and 56 women with a mean age of 42 years (12 to 78). The mean follow-up of 11 years (1 to 20) was identified from our pelvic fracture registry. There were 99 elementary and 154 associated fracture types. For the long-term clinical follow-up, 192 patients with complete data were included. Their mean age was 40 years (13 to 78) with a mean follow-up of 12 years (5 to 20). Injury to the femoral head and acetabular impaction were assessed with CT scans and patients with an ipsilateral fracture of the femoral head were excluded. Results. A total of 36 patients underwent total hip arthroplasty (THA). The overall ten-year survival of the hip joint was 86% (95% confidence interval (CI) 81% to 90%) and the 20-year survival was 82% (95% CI 76% to 87%). Injury to the femoral head and acetabular impaction were the strongest predictors of failure, with the long-term survival rate falling towards 50% in these patients. The survival fell to 0% at three years when both these risk factors were present in patients aged > 60 years. Conclusion. The long-term survival of the native hip joint after acetabular fractures was good, but the presence of injury to the femoral head and acetabular impaction proved to be strong predictors of failure, especially in patients aged > 60 years. These patients may be better treated with a combination of open reduction and internal fixation and primary arthroplasty. Cite this article: Bone Joint J 2017;99-B:834–40

Aims. Displaced, comminuted acetabular fractures in the elderly are increasingly common, but there is no consensus on whether they should be treated non-surgically, surgically with open reduction and internal fixation (ORIF), or with acute total hip arthroplasty (THA). A combination of ORIF and acute THA, an approach called ’combined hip procedure’ (CHP), has been advocated and our aim was to compare the outcome after CHP or ORIF alone. Patients and Methods. A total of 27 patients with similar acetabular fractures (severe acetabular impaction with or without concomitant femoral head injury) with a mean age of 72.2 years (50 to 89) were prospectively followed for a minimum of two years. In all, 14 were treated with ORIF alone and 13 were treated with a CHP. Hip joint and patient survival were estimated. Operating times, blood loss, radiological outcomes, and patient-reported outcomes were assessed. Results. No patient in the CHP group required further hip surgery, giving THA a survival rate of 100% (95% confidence interval (CI) 100 to 100) after three years, compared with 28.6% hip joint survival in the ORIF group (95% CI 12.5 to 65.4; p = 0.001). No dislocations or deep infections occurred in the CHP group. No patient died within the first year after index surgery, but patient survival was lower in the CHP group after three years. There were no relevant differences in patient-reported outcomes. Conclusion. The CHP confers a considerably reduced need of further surgery when compared with ORIF alone in elderly patients with complex acetabular fractures. These findings encourage both further use of, and larger prospective studies on, the CHP. Cite this article: Bone Joint J 2019;101-B:478–483

An increased prevalence of osteoarthritis (OA) in post-menopausal women has led to the suggestion that hormonal factors may play a role in the pathogenesis. This study aims to examine if undergoing a hysterectomy, both with retention and removal of ovaries, predisposes women to OA and secondly if the development is influenced by hormone replacement therapy (HRT). Statistical shape modelling (SSM) is a method of image analysis allowing for detection of subtle shape variation described by landmark points. Through the generation of linearly independent modes of variation, each image can be described in terms of numerical scores. 149 radiographs from female participants of the Osteoarthritis Initiative (OAI) were examined to compare hip morphology in those who had undergone hysterectomies compared to controls. No differences were observed in BMI, age, height or weight between groups. ANOVA and Games-Howell post-hoc analysis showed that modes 3 and 5 were statistically significant. Lower mode 3 scores were associated with hysterectomy (p=0.019), with narrowing of the femoral neck and increased acetabular coverage. Lower mode 5 scores were associated with hysterectomy and oophorectomy (p=0.049), displaying reduced coverage of the femoral head, superolateral migration of the femoral head and larger greater trochanter. No associations were observed between HRT use and OA. The subtle morphologic features of hip OA present in only hysterectomised women suggests undergoing a hysterectomy may be a predisposing factor and a clinical consideration. The use of HRT was not observed to influence the development of OA and thus cannot be suggested as a protective measure