Hip precautions following total hip arthroplasty (THA) limits flexion, adduction and internal rotation, yet these precautions cause unnecessary psychological stress. This study aims to assess bony and implant impingement using virtual models from actual patient's bony morphology and spinopelvic parameters to deduce whether hip precautions are necessary with precise implant positioning in the Asian population. Individualized sitting and standing sacral slope data of robotic THAs performed at two tertiary referral centers in Hong Kong was inputted into the simulation system based on patients’ pre-operative sitting and standing lumbar spine X-rays. Three-dimensional dynamic models were reconstructed using the Stryker Mako THA 4.0 software to assess bony and implant impingement both anteriorly and posteriorly, with default cup placement at 40° inclination and 20° anteversion. Femoral anteversion followed individual patient's native version. A 36mm hip ball was chosen for all cups equal or above 48mm and 32mm for those below. Anterior impingement was assessed by hip flexion and posterior impingement was assessed by hip extension. 113 patients were included. At neutral rotation and adduction, no patients had anterior implant impingement at hip flexion of 100°. 1.7% had impingement at 110°, 3.5% had impingement at 120°, 9.7% had impingement at 130°. With 20° of internal rotation and adduction, 0.8% had anterior implant impingement at hip flexion of 90°, 7.1% had impingement at 100° and 18.5% had impingement at 110°. With the hip externally rotated by 20°, 0.8% of patients had posterior implant impingement, and 8.8% bony impingement at 0° extension. With enabling technology allowing accurate component positioning, hip precautions without limiting forward flexion in neutral position is safe given precise implant positioning and adequate osteophyte removal. Patients should only be cautioned about combined internal rotation, adduction with flexion

Aims. This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum. Methods. Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement. Results. A total of 2,025 labral debridements (55%) and 1,659 labral repairs (45%) were identified. Both groups saw significant (p < 0.001) EQ-5D and iHOT-12 gain compared to preoperative scores at 12 months (iHOT-12 improvement: labral repair = +28.7 (95% confidence interval (CI) 26.4 to 30.9), labral debridement = +24.7 (95% CI 22.5 to 27.0)), however there was no significant difference between procedures after multivariable modelling. Overall, 66% of cases achieved the minimum clinically important difference (MCID) and 48% achieved substantial clinical benefit at 12 months. Conclusion. Both labral procedures were successful in significantly improving early functional outcome following hip arthroscopy, regardless of age or sex. Labral repair was associated with superior outcomes in univariable analysis, however there was no significant superiority demonstrated in the multivariable model. Level of evidence: III. Cite this article: Bone Jt Open 2022;3(4):291–301

Objectives. The aim of this study was to use registry data to report and compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum. Methods. Data on adult patients who underwent arthroscopic labral debridement or repair between January 2012 and March 2019 was extracted from the UK Non-Arthroplasty Hip Registry dataset. Patients who underwent microfracture, osteophyte excision or a concurrent extra-articular procedure were excluded. Outcomes comprised EuroQol-5 Dimensions (EQ-5D) index and the International Hip Outcome Tool 12 (iHOT-12), preoperatively and at 6 and 12 months. Results. A total of 3,553 arthroscopies comprising 1,986 labral debridement (56%) and 1,567 labral repairs (44%) were identified. Both groups saw significant (p <0.0001) EQ-5D and iHOT-12 gain compared to pre-operative baseline scores at 6 months (iHOT-12: repair = +27.4 (95%CI 25.2 to 29.5), debridement = +24.8 (95%CI 22.7 to 26.9)) which was maintained at 12 months (repair = +28.3 (95%CI 26.0 to 30.6), debridement = +24.3 (95%CI 22.0 to 26.5)) with improvement being significantly greater in the repair group by 12 months (p = 0.016) including after modelling for patient and surgical factors. Overall, 64% of cases achieved the minimum clinically important difference (MCID) and 47% achieved substantial clinical benefit (SCB: repair = 51%, debridement = 43%, p = 0.005) at 12 months. Significant functional improvement was seen for both genders and in younger and older (>40 years) cohorts. Conclusion. Both labral repair and debridement techniques were successful in significantly improving 12-month outcomes following hip arthroscopy regardless of age or gender. Labral repair was associated with superior outcomes in comparison to debridement. Whilst patient selection is crucial, our findings support the repair of an injured labrum where possible. A multi-centre randomised controlled trial would be the most appropriate next step to overcome bias inherent in the existing literature

Background. The purpose of this study was to report functional outcome scores following arthroscopic acetabular chondral procedures using the U.K. Non-Arthroplasty Hip Registry (NAHR). Methods. Data on adult patients who underwent hip arthroscopy between January 2012 and December 2018 was extracted from the NAHR. Patients who underwent femoral sided chondral procedures were excluded. Patients who underwent osteophyte excision or a concurrent extra-articular procedure were also excluded. Cases were then classified according to the acetabular chondral procedure performed – ‘chondroplasty’, ‘microfracture’ or ‘none’ (no chondral procedure recorded). Outcomes comprised EuroQol-5 Dimensions (EQ-5D) index and the International Hip Outcome Tool 12 (iHOT-12), preoperatively and at 6 and 12 months. Results. A total of 4,978 arthroscopies were identified (chondroplasty 26.4%, microfracture 5.4%, none 68.2%). Patients who underwent microfracture were significantly older (37.9y vs 37.3y) and of higher BMI (26.4 vs 25.8 kg/m2) than patients who underwent chondroplasty. Pre-operative, 6 and 12-month follow-up were available for 77%, 42% and 38% of cases respectively. This registry study found significant clinical improvement in all groups based on arthroscopic chondral procedure following hip arthroscopy. Patients who have microfracture seem to take longer to improve and have lower peak scores as compared with chondroplasty. All groups saw significant (p <0.0001) EQ-5D and iHOT-12 gain compared to pre-operative baseline scores at 6 months which was maintained at 12 months (12 month iHOT-12 gain: chondroplasty = +27.6 (95%CI 25.0 to 30.2), microfracture = +22.6 (95%CI 17.6 to 27.6), none = +25.4 (23.8 to 27.0)). There were no statistically significant between group differences in iHOT-12 gain. Comparing <40y vs >40y age groups, all saw significant improvements in baseline scores maintained up to 12 months however patients over 40y were slower to improve, particularly in microfracture with significantly poorer iHOT-12 gain at 6 months in comparison to patients under 40y but significance was lost by 12 months. Conclusion. Whilst patient selection is crucial (and we acknowledge selection bias as a key limitation), all three chondral procedures were effective at improving patient outcomes for both younger and older patients

Aims

It has been well documented in the arthroplasty literature that lumbar degenerative disc disease (DDD) contributes to abnormal spinopelvic motion. However, the relationship between the severity or pattern of hip osteoarthritis (OA) as measured on an anteroposterior (AP) pelvic view and spinopelvic biomechanics has not been well investigated. Therefore, the aim of the study is to examine the association between the severity and pattern of hip OA and spinopelvic motion.

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Computer-assisted 3D preoperative planning software has the potential to improve postoperative stability in total hip arthroplasty (THA). Commonly, preoperative protocols simulate two functional positions (standing and relaxed sitting) but do not consider other common positions that may increase postoperative impingement and possible dislocation. This study investigates the feasibility of simulating commonly encountered positions, and positions with an increased risk of impingement, to lower postoperative impingement risk in a CT-based 3D model.

Femoroacetabular impingement (FAI) is commonly associated with early hip arthritis. We reviewed our series of 1300 hip resurfacing procedures. More than 90% of our male patients, with an average age of 53 years, had cam impingement lesions. In this condition, there are anterior femoral neck osteophytes, and a retroverted femoral head on a normally anteverted neck. It is postulated that FAI results in collision of the anterior neck of the femur against the rim of the acetabulum, causing damage to the acetabular labrum and articular cartilage, resulting in osteoarthritis. Early treatment of FAI involves arthroscopic or open removal of bone from the anterior femoral neck, as well as repair or removal of labral tears. However, once osteoarthritis has developed, hip replacement or hip resurfacing is indicated. Hip resurfacing can re-orient the head and re-shape the neck. This helps to restore normal biomechanics to the hip, eliminate FAI, and improve range of motion. Since many younger men with hip arthritis have FAI, and are also considered the best candidates for hip resurfacing, it is evident that resurfacing has a role in these patients

Aims

The localization of necrotic areas has been reported to impact the prognosis and treatment strategy for osteonecrosis of the femoral head (ONFH). Anteroposterior localization of the necrotic area after a femoral neck fracture (FNF) has not been properly investigated. We hypothesize that the change of the weight loading direction on the femoral head due to residual posterior tilt caused by malunited FNF may affect the location of ONFH. We investigate the relationship between the posterior tilt angle (PTA) and anteroposterior localization of osteonecrosis using lateral hip radiographs.

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Precise implant positioning, tailored to individual spinopelvic biomechanics and phenotype, is paramount for stability in total hip arthroplasty (THA). Despite a few studies on instability prediction, there is a notable gap in research utilizing artificial intelligence (AI). The objective of our pilot study was to evaluate the feasibility of developing an AI algorithm tailored to individual spinopelvic mechanics and patient phenotype for predicting impingement.

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Spinopelvic pathology increases the risk for instability following total hip arthroplasty (THA), yet few studies have evaluated how pathology varies with age or sex. The aims of this study were: 1) to report differences in spinopelvic parameters with advancing age and between the sexes; and 2) to determine variation in the prevalence of THA instability risk factors with advancing age.

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The primary objective of this study was to develop a validated classification system for assessing iatrogenic bone trauma and soft-tissue injury during total hip arthroplasty (THA). The secondary objective was to compare macroscopic bone trauma and soft-tissues injury in conventional THA (CO THA) versus robotic arm-assisted THA (RO THA) using this classification system.

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Achieving accurate implant positioning and restoring native hip biomechanics are key surgeon-controlled technical objectives in total hip arthroplasty (THA). The primary objective of this study was to compare the reproducibility of the planned preoperative centre of hip rotation (COR) in patients undergoing robotic arm-assisted THA versus conventional THA.

We treated 31 hips in 30 patients with advanced osteoarthritis of the hip secondary to acetabular dysplasia, by valgus-extension femoral osteotomy. The mean follow-up was 12.7 years (10 to 17). Acetabuloplasty was added in ten severely dysplastic hips. In 28 hips, radiological widening of the joint space was seen three years after operation, but in 12 had narrowed again by ten years. Survivorship analysis showed that the rate of survival was 82% using the pain score as the index of failure, and 72% based on radiological findings at ten years. Better long-term results were obtained in hips which had an acetabular head index greater than 70% or a roof osteophyte more than 5 mm in length three years after operation. Acetabuloplasty should be added for the hip which is severely dysplastic and with a poorly developed roof osteophyte

We treated 31 consecutive patients of mean age 43 years (22 to 59) with severe osteoarthritis of the hip secondary to dysplasia by valgus-extension osteotomy. The clinical results were analysed for factors which may have affected the outcome. The procedure was carried out only on one side and was combined with a Chiari pelvic osteotomy in four patients. The angle of valgus was between 30 and 40° with 10 to 20° of extension. The mean follow-up was 15 years (12 to 18). Clinical evaluation using Charnley’s modification of the system of Merle d’Aubigné and Postel showed that the mean score for pain had improved from 2.3 before operation to 4.2 at 15 years, and function from 2.3 to 4.2. Range of movement had decreased from 4.2 to 3.5. Fifteen patients (48.4%) had a pain score of 5 or 6 and were evaluated as satisfactory. Kaplan-Meier survivorship analysis showed a survival rate of 51% at 15 years after operation. Two preoperative factors had a significant positive correlation with the radiological results, namely the thickness of the capital drop osteophyte and the length of the roof osteophyte. We suggest that this procedure is effective for advanced osteoarthritis in the dysplastic hip in young and active patients if these factors are satisfactory on the preoperative radiographs

Aims

Pelvic tilt is believed to affect the symptomology of osteoarthritis (OA) of the hip by alterations in joint movement, dysplasia of the hip by modification of acetabular cover, and femoroacetabular impingement by influencing the impingement-free range of motion. While the apparent role of pelvic tilt in hip pathology has been reported, the exact effects of many forms of treatment on pelvic tilt are unknown. The primary aim of this study was to investigate the effects of surgery on pelvic tilt in these three groups of patients.

Evaluation of the anatomical features, details of surgical technique and results of the THA in patients with CDH (type C1 and C2 by G. Hartofilakidis). From 2001 to 2016 years one surgical team performed 683 THA in patients with CDH. We retrospectively studied 561 total hip arthroplasties in 349 patients, follow-up rate was 82.1%, from 12 to 188 months (mean 69.4). The results were evaluated by clinical examination, X-rays analysis, Harris Hip Score. Unilateral high hip dislocation was observed in 175 patients (31.2%), in these cases often have underdeveloped half of the pelvis on the side of the dislocation. Type C1 was observed in 326 cases and type C2 – in 235 cases. Type C1 in comparison with C2 has less leg length discrepancy, developed shape of proximal femur, presence of supraacetabular osteophyte. The mean displacement of femoral head was 47.6 mm (from 29 to 55) for C1 and 63.4 mm (from 41 to 78) for C2. Average offset in C1 was 50.1 mm (37–63) and in C2 − 44.3 mm (34–52). Shortening osteotomy by T. Paavilainen performed in 165 cases (50.6%) with C1 dysplasia and in 235 cases (100%) with C2. The features of surgical technique were small size of the cups with obligatory additional screw fixation of the cup and small offset of the stems. The cup was positioned into the true acetabulum in 99.1% cases of C2 type, for C1 – only 69.0%). The cups size 44 mm were used in 97.3% cases for type C2 and in 78.6% cases for type C1. For shortening osteotomy in 76.3% cases Wagner Cone stems were used. Early complications included 9 dislocations (1.6%), 8 femoral nerve neuropathies (1.4%) and 3 infections (0.5%). There is no sciatic nerve palsy. Late complications included dislocation in two hips (1.1%), nonunion of the greater trochanter (8.4%), aseptic loosening of the femoral component − 2 (0.8 %), aseptic loosening of the cup − 11 (1.6%). Average Harris Hip score improved from 39.5 to 83.6 with unsignificant diffence between types C1 and C2 (from 37.3 to 81.4 and from 40.4 to 85.1 consequently). Revision rate was 2.1% for type C1 and 5.5% for type C2. Hip replacement surgery in patients with high hip dislocation is very challenging. Type C2 dysplasia has only one surgical option with good long-term results – placement of the cup into the true acetabulum and shortening osteotomy. Its advantages include leg length alignment and decreased risk of sciatic nerve injury. Type C1 dysplasia presents more heterogenic group of patients and allows to use several surgical options – different placement of the cup and surgical approach without shortening osteotomy. Functional results in patients with type C1 are a little bit worse in comparison with type C2, but C1 had less risk of complications. The main problem of shortening osteotomy by Paavilainen is delayed union and non-union of great trochanter

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This study aimed to evaluate sagittal spinopelvic alignment (SSPA) in the early stage of rapidly destructive coxopathy (RDC) compared with hip osteoarthritis (HOA), and to identify risk factors of SSPA for destruction of the femoral head within 12 months after the disease onset.

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Adult patients with history of childhood infection pose a surgical challenge for total hip arthroplasty (THA) due to distorted bony anatomy, soft-tissue contractures, risk of reinfection, and relatively younger age. Therefore, the purpose of the present study was to determine clinical outcome, reinfection rate, and complications in patients with septic sequelae after THA.

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The aim of this study was to determine whether total hip arthroplasty (THA) for chronic hip pain due to unilateral primary osteoarthritis (OA) has a beneficial effect on cognitive performance.

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This study aimed to use intraoperative free electromyography to examine how the placement of a retractor at different positions along the anterior acetabular wall may affect the femoral nerve during total hip arthroplasty (THA) when undertaken using the direct anterior approach (THA-DAA).