Extensive and severe bone loss of the femur may be a result of a failed total hip arthroplasty (THA) or total knee arthroplasty (TKA) with multiple revision surgeries which may be caused by factors such as infection, periprosthetic fracture or osteolysis. The aim of this study was to assess outcomes of using the “Push-Through Total Femoral Prosthesis” (PTTF) for revision of a total hip replacement with extreme bone loss. Fourteen patients who had extensive bone defects of the femur due to failed THR's and were treated with PTTF between 2012 and 2020 were included in this study. Primary functional outcomes were assessed using Harris Hip Score (HHS), Toronto Extremity Salvage Score (TESS) and Musculoskeletal Tumor Society (MSTS) scores. Range of motion, complications, and ambulatory status were also recorded to assess secondary outcomes. Two of 14 patients underwent surgery with PTTF for both knee and hip arthroplasty revision. The mean time between index surgery and PTTF was 15 years (3 to 32 yrs.). Acetabular components were revised in six of 14 patients. After a mean follow-up of 5.9 years, hip dislocations occurred in 3 patients. All dislocated hips were in patients with retained non-constrained acetabular bearings. Patient satisfaction was high (MSTS: 67%, HHS: 61.2%, TESS 64.6%) despite a high re-operation rate and minor postoperative problems. PTTF is a unique alternative that may be considered for a failed THA revision procedure in patients with an extreme femoral bone defect. Patients are able to ambulate pain free relatively well. Routine usage of constrained liners should be considered to avoid hip dislocation which was our main problem following the procedure

Introduction. Management of Vancouver type B1 and C periprosthetic fractures in elderly patients requires fixation and an aim for early mobilisation but many techniques restrict weightbearing due to re-fracture risk. We present the clinical and radiographic outcomes of our technique of total femoral plating (TFP) to allow early weightbearing whilst reducing risk of re-fracture. Methods. A single-centre retrospective cohort study was performed including twenty-two patients treated with TFP for fracture around either hip or knee replacements between May 2014 and December 2017. Follow-up data was compared at 6, 12 and 24 months. Primary outcomes were functional scores (Oxford Hip or Knee score (OHS/OKS)), Quality of Life (EQ-5D) and satisfaction at final follow-up (Visual Analogue Score (VAS)). Secondary outcomes were radiographic fracture union and complications. Results. Mean OHS and OKS was 50.25, EQ-5D score was >4 for all modalities, VAS was 64.4/100. Radiographs demonstrated bony union in 58% at 3 months and 76% at 6 months. We identified no case of re-fracture however non-union occurred in 4 patients. No other operative complications were identified. Conclusion. These results suggest that TFP may be a safe, viable option for management of periprosthetic fractures around stable implants allowing the benefit of early weightbearing, satisfactory outcomes and low re-fracture risk

Introduction: Total femoral endoprosthetic replacement can be an alternative to amputation following extensive tumour excision or in cases of severe bone loss. In skeletally immature patients the problem of leg length inequality may be overcome by the use of extendable prostheses. The aim of this study is to assess the functional outcome of patients following total femoral endoprosthetic replacement. Methods: This is a retrospective, single centre study of 16 patients who underwent consecutive total femoral replacements between 1978 and 1999. Information was collected from the Bone Tumour database, medical records and clinical review. The prostheses were custom made by the Biomedical Engineering Department of University College London and Stanmore Implants Worldwide. The implants are composed of a Titanium alloy shaft with Cobalt-Chrome bearing surfaces, incorporating a SMILES (Stanmore Modular Individualised Lower Extremity System) knee joint. Outcome was assessed using the Musculoskeletal Tumour Society (MTS) rating score. Sample: Eight patients were male and eight female. Mean age was 35 years (range 5–75 years). Ten patients underwent total femoral replacement as a primary procedure; nine for malignant tumour and one for hydatid disease. Of the patients with malignancy five had metastases at the time of presentation. The other indications were failed distal femoral replacement in four cases and periprosthetic fractures in the remaining two. Four children received extendable prostheses. Results: Of the patients with malignant disease, all but one had complete tumour excision. Three patients developed local recurrence. Two patients died of metastases within one year of diagnosis and three more died within five years. Three required revision procedures. Two more dislocated at the hip joint. Other complications included infection and lymphoedema. In patients surviving longer than one year the average range of motion at the hip was 85 degrees and at the knee 80 degrees. Using the MTS rating score the mean functional outcome was 60% of normal (range 27–90%). Of the survivors one achieved an excellent result, five were good, four fair and one poor. Conclusion: Total femoral endoprosthetic replacement can be effective in limb salvage and provide an alternative to amputation. Good functional results can often be achieved. However, the complication rate is high and the outcome extremely varied

Salvage procedures for complications following revision arthroplasty are becoming an increasingly necessary intervention. Total femoral replacement (TFR), initially developed for limb salvage in the management of bone malignancy is the most extreme example of this. Over the last 25 years, 14 patients have undergone TFR at the author’s institution following complications of revision arthroplasty surgery. We have retrospectively reviewed the medical records and radiographs on this patient group (in terms of operative indication, morbidity and mortality). The clinical outcome has been evaluated using the International Symposium of Limb salvage (ISOLS) criteria. 14 patients, 9 male 5 female were treated with TFR between 1978 and 2003. The average age was 64 years (range 44–79 years). The duration of symptoms from primary intervention to total femoral replacement was on average 8 years (range 1–15 years) and during this period the number of revision procedures undertaken ranged from 1– 4. In 86 % of cases the operative indication for TFR was for the management of deep sepsis. Other indications include non-union and periprosthetic fracture with massive bone loss. The post operative course was varied with 4 patients experiencing no significant complications, 2 needing further surgery as a consequence of infection, 5 needed surgery for dislocation with 2 of these patients being left with a permanently dislocated hip. As all patients had undergone some form of limb salvage procedure prior to TFR their level of function was assessed pre-operatively by the ISOLS criteria. This showed a range 0 – 33% (poor function). Clinical outcome following TFR measured by the same ISOLS criteria showed a range 36 – 80% (poor to good function). Total femoral replacement has a definite role in the management of complex problems arising following hip and knee revision arthroplasty surgery. Pain can be controlled to an acceptable level and independence can be maintained

Introduction: Total femoral endoprosthetic replacement can be used as an alternative to hip disarticulation following extensive tumour excision or in cases of more severe bone loss. To date there have been no long term studies on the oncological and functional outcome of patients who have had this procedure for malignant bone disease. We report our experience of over 25 years employing this procedure using a custom-made and modular total femoral endoprosthetic replacement. Methods: This is a retrospective, single centre study of 27 patients who underwent consecutive total femoral replacement as a primary procedure between 1978 and 2005. Information was collected from the bone tumour database, medical records and clinic review. Outcome was assessed using the Musculoskeletal Tumour Society (MSTS) rating score, the Harris Hip Score (HHS) and the Oxford Knee Score (OKS). Results: There were 15 males and 12 females, with a mean age of 30 years (5 to 65). The overall mean follow-up was 4.3 years (1 to 16.4) for all patients, 9.1 years (1 to 16.4) for the 7 patients who were alive at the time of this review, and 2.6 years (1 to 13) for the 20 patients who had died. 24 patients had primary malignant bone tumours of the femur and 3 had metastatic disease from a known primary elsewhere. 3 patients developed local recurrence, 1 patient developed new lung metastases. Mean MSTS score was 63% (19/30), mean HHS was 68/100 and mean OKS was 34/48. Discussion: Total femoral replacement can be an effective alternative to hip disarticulation in patients with malignant bone disease. Good functional outcomes can be achieved without compromising survival

Introduction and Aims: Periprosthetic femur fractures, severe bone loss with loosening, infection and debridements, and non-union can all result in loss of bone stock following total hip (THA) and/or total knee arthroplasty (TKA). In the multiply-operated or osteopenic patient, few options exist when bone is severely compromised. We report results of a total femoral construct to salvage the severely compromised femur. Method: We retrospectively reviewed 59 consecutive total femurs. Revision THA and/or TKA was performed utilising a custom total femoral construct: a constrained acetabular component, proximal femoral replacement, diaphyseal segment, and rotating hinge knee. Return to ambulation, pain, functional capacity, and subsequent surgery outcomes were measured. All cases involved severe bone loss: 13 aseptic loosening of revision THA and TKA, 24 periprosthetic fractures, five failed non-unions around implants, and 17 cases of multiple debridements for sepsis. Results: Mean age was 74 years, mean follow-up was 38 months. One peri-operative death occurred. Pain scores improved by 18 points. Average post-operative hip flexion was 90 and knee flexion 93. All but one patient achieved ambulatory capability. Four of 17 septic cases recurred, three successfully treated and one disarticulation. Three other infections occurred in the aseptic and periprosthetic groups, all treated successfully. There were five dislocations, one acetabular revision, and two knee revisions for aseptic loosening. Conclusion: Total femoral replacement represents a viable salvage procedure for the compromised femur associated with THA and/or TKA. Rapid return to ambulating, relief of pain and improved function can be expected from this, the ultimate revision surgery

Purpose: Few functional outcomes of total femoral endoprosthetic replacement (TFEPR) using contemporary modular systems are available. We compared functional results between TFEPR patients receiving fixed- and rotating-hinge knee componentry following oncologic resections. Method: Eighteen TFEPR patients were identified from a prospectively gathered sarcoma database. Six were secondary procedures and 12 primary. Four patients had metastatic carcinoma, 8 osteosarcoma, 4 non-osteogenic spindle cell sarcomas of bone, 1 Ewing’s sarcoma, and 1 femur-invading soft-tissue sarcoma. All reconstructions used modular implants from a single company. Proximally, all were bipolar hip hemiarthoplasties, 12 including abductor reattachment. Distally, 8 had fixed- and 10 had rotating-hinge knee componentry. Toronto Extremity Salvage Score (TESS), and both Musculoskeletal Tumor Society Scores (MSTS) were compared between fixed- and rotating-hinge groups using the Mann-Whitney test. Results: Complications included 1 hip dislocation, 1 femoral malrotation, and wound problems requiring 3 debridements and 1 amputation. One metastatic carcinoma patient developed local relapse. Follow-up averaged 4 years (range 1 month to 14 years). At latest follow-up, 10 patients had died of disease. Eight remained alive, 6 disease-free, 2 with distant disease. Among patients surviving 6 months, 6 used no assistive devices, 5 used a single cane, and 4 were wheelchair bound, each at least partly due to distant disease progression. TESS averaged 74.5±17.4, MSTS1987 25.2±4.4; and MSTS1993 58.6±22.9 among the 12 patients for whom functional results were available from latest follow-up. No statistically significant differences or even trends were detected between fixed-hinge and rotating-hinge patients (lowest p = 0.755), but both instability problems were in the rotating-hinge group. Conclusion: While both rotating- and fixed-hinge TFEPR reconstructions may function well, consideration should be given to fixed-hinge knee reconstruction when massive myectomies or poorer conditioning make hip and knee stability a primary concern in the short-term

Introduction

Total knee arthroplasty (TKA) femoral components are known to wear and roughen with clinical use, and reaction to metal is a well-documented complication of TKA. Ceramic materials are resistant to wear and corrosion, but the surface wear of ceramic femoral components in TKA has not been reported. This study measured the changes in roughness and mass lost from cobalt-chromium (CoCr) femoral components tested in a knee simulator, and compared them to those observed in ceramic components.

Abstract. Introduction. Patients presenting with loosening or a fracture between ipsilateral hip and knee replacements provide a unique reconstructive challenge. We present mid-term results of the cement-over megaprosthesis (COM) when managing these complex cases. A COM is cement-linked to the stem of a well-fixed existing implant. We report the largest series to date and show that this may be preferable to total femoral replacement in a cohort of patients who often have significant co-morbidities. Methodology. A retrospective analysis of patients undergoing COM between 2002–2022 was performed. Primary outcomes were defined as implant survival, displayed with survival analysis. Secondary outcomes included mortality and surgical complications. Functional outcomes included Visual Analogue Score (VAS), EuroQol-5D-3L and Musculoskeletal Tumour Society (MSTS) score at one year post operatively. Results. 34 patients underwent reconstructive cement-over technique. There were 20 custom distal femur replacements and 10 custom proximal femoral replacements. Two patients were revised, with a ten year implant survival of 94%. Fifteen patients died during the study period with an mean time to death of 66 months (25–109). The mean follow up was 75 months. 11 patients (32%) developed surgical complications. Mean VAS score was 4.9 (1–10), EuroQol-5D-3L index 0.45 (−0.59 – 0.88) and MSTS score was 16.8 (2–27) in 29 patients. Conclusion. The COM technique provides good implant survivorship in complex cases with compromised bone stock and this series confirms this as an established alternative to total femoral replacement in these cases

Aims. Both the femoral and tibial component are usually cemented at revision total knee arthroplasty (rTKA), while stems can be added with either cemented or press-fit (hybrid) fixation. The aim of this study was to compare the long-term stability of rTKA with cemented and press-fitted stems, using radiostereometric analysis (RSA). Methods. This is a follow-up of a randomized controlled trial, initially involving 32 patients, of whom 19 (nine cemented, ten hybrid) were available for follow-up ten years postoperatively, when further RSA measurements were made. Micromotion of the femoral and tibial components was assessed using model-based RSA software (RSAcore). The clinical outcome was evaluated using the Knee Society Score (KSS), the Knee injury and Osteoarthritis Outcome Score (KOOS), and visual analogue scale (pain and satisfaction). Results. The median total femoral translation and rotation at ten years were 0.39 mm (interquartile range (IQR) 0.20 to 0.54) and 0.59° (IQR 0.46° to 0.73°) for the cemented group and 0.70 mm (IQR 0.15 to 0.77) and 0.78° (IQR 0.47° to 1.43°) for the hybrid group. For the tibial components this was 0.38 mm (IQR 0.33 to 0.85) and 0.98° (IQR 0.38° to 1.34°) for the cemented group and 0.42 mm (IQR 0.30 to 0.52) and 0.72° (IQR 0.62° to 0.82°) for the hybrid group. None of these values were significantly different between the two groups and there were no significant differences between the clinical scores in the two groups at this time. There was only one re-revision, in the hybrid group, for infection and not for aseptic loosening. Conclusion. These results show good long-term fixation with no difference in micromotion and clinical outcome between fully cemented and hybrid fixation in rTKA, which builds on earlier short- to mid-term results. The patients all had type I or II osseous defects, which may in part explain the good results. Cite this article: Bone Joint J 2022;104-B(7):875–883

Introduction. The prevalence of ipsilateral total hip arthroplasty (THA) and total knee arthroplasty (TKA) is rising in concert with life expectancy, putting more patients at risk for interprosthetic femur fractures (IPFF). Our study aimed to assess treatment methodologies, implant survivorship, and clinical outcomes of patients with IPFF. Methods. 77 patients treated for an IPFF from 1985–2017 at a single large referral center were reviewed. Prior to the fracture, at the hip/knee sites respectively 46 femurs had primary/primary, 21 had revision/primary, 3 had primary/revision and 7 had revision/revision components. Mean age and BMI were 74 years and 30 kg/m. 2. , respectively. Mean follow-up after fracture treatment was 7 years. Results. Sixty fractures were classified as Vancouver C (UCS D) while 17 were Vancouver B (UCS B). Fifty-seven patients (74%) were treated with ORIF; 3 developed a non-union, 3 developed a PJI, and 2 developed aseptic loosening. Nineteen patients (25%) were treated with revision arthroplasty including: 13 revision THAs, 4 distal femoral replacements, 1 revision TKA, and 1 total femoral replacement of which 2 developed aseptic loosening and 2 developed a non-union. Survivorship free from any reoperation for the entire cohort was 79% at 2 years. Patients in the ORIF group who went on to union tended to have stemmed components and greater interprosthetic distance (IPD=189mm vs. 163mm, p=0.55) than non-united fractures. Patients who went on to nonunion in the revision arthroplasty group had higher medullary diameter: cortical width ratio (2.5 vs. 1.3, p=0.01) and lower IPD (36mm vs. 202mm, p=0.002). 95% of patients were ambulatory at latest follow-up. Conclusion. Interprosthetic femur fractures are technically and biologically challenging cases. An individualized approach of internal fixation versus revision arthroplasty led to a 79% success rate free of reoperation at 2 years with 95% of patients ambulatory. Continued improvements in management are warranted

Aims

The aim of this study was to investigate whether anterior pelvic plane-pelvic tilt (APP-PT) is associated with distinct hip pathomorphologies. We asked: is there a difference in APP-PT between young symptomatic patients being evaluated for joint preservation surgery and an asymptomatic control group? Does APP-PT vary among distinct acetabular and femoral pathomorphologies? And does APP-PT differ in symptomatic hips based on demographic factors?

Aims

Custom-made partial pelvis replacements (PPRs) are increasingly used in the reconstruction of large acetabular defects and have mainly been designed using a triflange approach, requiring extensive soft-tissue dissection. The monoflange design, where primary intramedullary fixation within the ilium combined with a monoflange for rotational stability, was anticipated to overcome this obstacle. The aim of this study was to evaluate the design with regard to functional outcome, complications, and acetabular reconstruction.

Aims

This study aimed to develop and validate a fully automated system that quantifies proximal femoral bone mineral density (BMD) from CT images.

Aims. There are concerns regarding initial stability and early periprosthetic fractures in cementless hip arthroplasty using short stems. This study aimed to investigate stress on the cortical bone around the stem and micromotions between the stem and cortical bone according to femoral stem length and positioning. Methods. In total, 12 femoral finite element models (FEMs) were constructed and tested in walking and stair-climbing. Femoral stems of three different lengths and two different positions were simulated, assuming press-fit fixation within each FEM. Stress on the cortical bone and micromotions between the stem and bone were measured in each condition. Results. Stress concentration was observed on the medial and lateral interfaces between the cortical bone and stem. With neutral stem insertion, mean stress over a region of interest was greater at the medial than lateral interface regardless of stem length, which increased as the stem shortened. Mean stress increased in the varus-inserted stems compared to the stems inserted neutrally, especially at the lateral interface in contact with the stem tip. The maximum stress was observed at the lateral interface in a varus-inserted short stem. All mean stresses were greater in stair-climbing condition than walking. Each micromotion was also greater in shorter stems and varus-inserted stems, and in stair-climbing condition. Conclusion. The stem should be inserted neutrally and stair-climbing movement should be avoided in the early postoperative period, in order to preserve early stability and reduce the possibility of thigh pain, especially when using a shorter stem. Cite this article: Bone Joint Res 2021;10(4):250–258

Regulatory bodies impose stringent pre-market controls to certify the safety and compatibility of medical devices. However, internationally recognized standard tests may be expensive, time consuming and challenging for orthopedic implants because of many possible sizes and configurations. In addition, cost and time of standard testing may endanger the feasibility of custom-device production obtained through innovative manufacturing technologies like 3d printing. Modeling and simulation (M&S) tools could be used by manufactures and at point-of-care to improve design confidence and reliability, accelerate design cycles and processes, and optimize the amount of physical testing to be conducted. We propose an integrated cloud platform to perform in silico testing for orthopedic devices, assessing mechanical safety and electromagnetic compatibility, in line with recognized standards and regulatory guidelines. The . InSilicoTrials.com. platform contains two M&S tools for orthopedic devices: CONSELF and NuMRis. CONSELF (. conself.com. ) uses Salome-Meca 2017 to compute static implant stresses and strains on metallic orthopedic devices, following the requirements and considerations of ASTM F2996-20 for non-modular hip femoral stems and ASTM F3161-16 for total knee femoral components. Simulation results were consistent with those reported in the two standards. NuMRis (. numris.insilicomri.com. ) uses ANSYS HFSS and ANSYS Mechanical 2019R3 to compute radio-frequency energy absorption and induced heating in 1.5T and 3T MRI coils, replicating the ASTM F2182-19e2 Standard Test Method. Simulation results were validated against in vitro measurements. The integrated M&S workflow on the cloud platform allows the user to upload the 3D geometry and the material properties of the orthopedic device to be tested, automatically set up the standard testing scenarios, run simulations and process outcome, with the option to summarize the results in accordance with current FDA guidance on M&S reporting. The easy-to-use interfaces of InSilicoTrials tools run through commercial web browsers, requiring no specific expertise in computational methods or additional on-premise software and hardware resources, since all simulations are run remotely on cloud infrastructure. The integrated cloud platform can be used to evaluate design alternatives, test multi-configuration devices, perform multi-objective design optimization and identify worst-case scenarios within a family of implant sizes, or to assess the safety and compatibility of custom-made orthopedic devices. InSilicoTrials.com. is the first cloud platform offering a collection of M&S tools to perform in silico standard testing for orthopedic devices. The proposed tools allow to assess mechanical safety and electromagnetic compatibility before prototyping, preventing risks and criticalities for the patient, and helping manufacturers and point-of-care to accelerate time and reduce costs during the device development. The proposed platform promotes the broader adoption of digital evidence in preclinical trials, supporting the device submission process and pre-market regulatory evaluation, and helping secure regulatory approval

Aims

The aim of this modified Delphi process was to create a structured Revision Hip Complexity Classification (RHCC) which can be used as a tool to help direct multidisciplinary team (MDT) discussions of complex cases in local or regional revision networks.

Repeat revision hip replacements can lead to severe bone loss necessitating salvage procedures such as proximal or total femoral replacement. We present medium term outcomes from our experience of the Limb Preservation System (LPS) in patients with failed revision hip arthroplasties. All patients undergoing proximal femoral or total femoral replacement from 2003–2007 at our unit were reviewed. Data was collected preoperatively and at annual assessment post procedure for a minimum of 5 years. This included clinical review, functional outcome scores (WOMAC, Oxford Hip Score, Harris Hip Score) and radiographic evaluation. A total of 17 patients underwent femoral replacement (13 proximal, 4 total) using the LPS during the study period. Within this cohort there were 13 males and 4 females with a mean age of 64 years (range 47–86). Median follow up was 7 years (range 5–9 years). Primary diagnoses were DDH (7), Primary OA (5), RA (2), proximal femoral fracture (2) and phocomelia (1). Five patients (29%) required further revision surgery for infection (2 patients) or recurrent dislocations (3 patients). No stems required revision due to aseptic loosening or stem failure at 5–9 years. Compared to preoperative assessment, there was significant improvement in median outcome scores at 5 years (WOMAC increased by 33 points, Oxford hip score by16 points and Harris hip score by 43 points). 82% of patients maintained functional independence at latest review. The Limb Preservation System offers a salvage procedure for failed revision total hip arthroplasty with significant symptom and functional improvement in most patients at medium term follow up

Summary. The dGEMRIC index correlates more strongly with the pattern of radiographic joint space narrowing in hip osteoarthritis at five year follow-up than morphological measurements of the proximal femur. It therefore offers potential to refine predictive models of hip osteoarthritis progression. Introduction. Longitudinal general population studies have shown that femoroacetabular impingement increases the risk of developing hip osteoarthritis, however, morphological parameters have a low positive predictive value. Arthroscopic debridement of impingement lesions has been proposed as a potential strategy for the prevention of osteoarthritis, however, the development of such strategies requires the identification of individuals at high risk of disease progression. We investigated whether delayed Gadolinium-Enhanced MRI of Cartilage (dGEMRIC) predicts disease progression. This imaging modality is an indirect measure of cartilage glycosaminoglycan content. Patients and Methods. 34 asymptomatic individuals from a longitudinal cohort study (sibkids) were assessed at baseline with the collection of Patient Reported Outcome Measures (PROMs), anteroposterior and cross-table lateral radiographs, 3D morphological MRI, and dGEMRIC at 3T of their index hip. A dGEMRIC index was calculated as a ratio of the anterosuperior acetabular cartilage T1 relaxation time and the total femoral and acetabular cartilage T1 relaxation time. 29 individuals were followed up at 5 years for repeat assessment (average age 51 years and range 36 to 67). Radiological measurements were made by a single observer using in house Hipmorf software. Radiographic disease progression was assessed using minimum joint space width (JSW), lateral sourcil JSW, and medial sourcil JSW. These were measured on baseline and five year follow-up anteroposterior radiographs with an intra-observer ICC of 0.916. Alpha angle measurements were made by the same observer on radiographs and MRI radial slices with an intra-observer ICC of 0.926. Results. Mean minimum JSW for the cohort fell by 0.16mm over five years (p=0.024). Baseline dGEMRIC index did not correlate with change in minimum JSW (r=0.031 p=0.873). There was a moderate correlation between baseline dGEMRIC and the direction of JSW loss (change in JSW at the lateral sourcil minus change in JSW at the medial sourcil) (r=0.561 p=0.002). There was a weak correlation between the change in Non-Arthritic Hip Score and baseline dGEMRIC (r=0.256 P=0.180). Maximum alpha angle measured on baseline MRI radial slices did not correlate with change in minimum JSW and weakly correlated with the direction of JSW narrowing (r=0.273 p=0.160). Conclusion. A low dGEMRIC index indicates reduced glycosaminoglycan concentration in the anterosuperior acetabular cartilage compared with the total femoral and acetabular cartilage. This correlates with lateral JSW narrowing relative to medial JSW narrowing as osteoarthritis progresses. The dGEMRIC index correlates better with osteoarthritis progression than alpha angle measurements and offers the potential to refine a predictive model for osteoarthritis progression to aid patient selection for clinical trials

Aims

The effect of pelvic tilt (PT) and sagittal balance in hips with pincer-type femoroacetabular impingement (FAI) with acetabular retroversion (AR) is controversial. It is unclear if patients with AR have a rotational abnormality of the iliac wing. Therefore, we asked: are parameters for sagittal balance, and is rotation of the iliac wing, different in patients with AR compared to a control group?; and is there a correlation between iliac rotation and acetabular version?