Aims. Navigation devices are designed to improve a surgeon’s accuracy in positioning the acetabular and femoral components in total hip arthroplasty (THA). The purpose of this study was to both evaluate the accuracy of an optical computer-assisted surgery (CAS) navigation system and determine whether preoperative spinopelvic mobility (categorized as hypermobile, normal, or stiff) increased the risk of acetabular component placement error. Methods. A total of 356 patients undergoing primary THA were prospectively enrolled from November 2016 to March 2018. Clinically relevant error using the CAS system was defined as a difference of > 5° between CAS and 3D radiological reconstruction measurements for acetabular component inclination and anteversion. Univariate and multiple logistic regression analyses were conducted to determine whether hypermobile (. Δ. sacral slope(SS). stand-sit. > 30°), or stiff (. ∆. SS. stand-sit. < 10°) spinopelvic mobility contributed to increased error rates. Results. The paired absolute difference between CAS and postoperative imaging measurements was 2.3° (standard deviation (SD) 2.6°) for inclination and 3.1° (SD 4.2°) for anteversion. Using a target zone of 40° (± 10°) (inclination) and 20° (± 10°) (anteversion), postoperative standing radiographs measured 96% of acetabular components within the target zone for both inclination and anteversion. Multiple
Transfusion after primary total hip arthroplasty (THA) has become rare, and identification of causative factors allows preventive measures. The aim of this study was to determine patient-specific factors that increase the risk of needing a blood transfusion. All patients who underwent elective THA were analyzed retrospectively in this single-centre study from 2020 to 2021. A total of 2,892 patients were included. Transfusion-related parameters were evaluated. A multiple logistic regression was performed to determine whether age, BMI, American Society of Anesthesiologists (ASA) grade, sex, or preoperative haemoglobin (Hb) could predict the need for transfusion within the examined patient population.Aims
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This study aimed to describe preoperative waiting times for surgery in hip fracture patients in Norway, and analyze factors affecting waiting time and potential negative consequences of prolonged waiting time. Overall, 37,708 hip fractures in the Norwegian Hip Fracture Register from January 2014 to December 2018 were linked with data in the Norwegian Patient Registry. Hospitals treating hip fractures were characterized according to their hip fracture care. Waiting time (hours from admission to start of surgery), surgery within regular working hours, and surgery on the day of or on the day after admission, i.e. ‘expedited surgery’ were estimated.Aims
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Aims. This study aims to assess the relationship between history of pseudotumour formation secondary to metal-on-metal (MoM) implants and periprosthetic joint infection (PJI) rate, as well as establish ESR and CRP thresholds that are suggestive of infection in these patients. We hypothesized that patients with a pseudotumour were at increased risk of infection. Methods. A total of 1,171 total hip arthroplasty (THA) patients with MoM articulations from August 2000 to March 2014 were retrospectively identified. Of those, 328 patients underwent metal artefact reduction sequence MRI and had minimum two years’ clinical follow-up, and met our inclusion criteria. Data collected included demographic details, surgical indication, laterality, implants used, history of pseudotumour, and their corresponding preoperative ESR (mm/hr) and CRP (mg/dl) levels. Multivariate logistic regression modelling was used to evaluate PJI and history of pseudotumour, and receiver operating characteristic curves were created to assess the diagnostic capabilities of ESR and CRP to determine the presence of infection in patients undergoing revision surgery. Results. The rate of PJI for all identified MoM THAs was 3.5% (41/1,171), with a mean follow-up of 10.9 years (2.0 to 20.4). Of the patients included in the final cohort, 8.2% (27/328) had PJI, with a mean follow-up of 12.2 years (2.3 to 20.4). Among this cohort, 31.1% (102/328) had a history of pseudotumour. The rate of PJI in these patients was 14.7% (15/102), which was greater than those without pseudotumour, 5.3% (12/226) (p = 0.008). Additionally,
Aims. The aims of this study were to determine the incidence and factors for developing periprosthetic joint infection (PJI) following hemiarthroplasty (HA) for hip fracture, and to evaluate treatment outcome and identify factors associated with treatment outcome. Methods. A retrospective review was performed of consecutive patients treated for HA PJI at a tertiary referral centre with a mean 4.5 years’ follow-up (1.6 weeks to 12.9 years). Surgeries performed included debridement, antibiotics, and implant retention (DAIR) and single-stage revision. The effect of different factors on developing infection and treatment outcome was determined. Results. A total of 1,984 HAs were performed during the study period, and 44 sustained a PJI (2.2%). Multiple
Aims. Rotational acetabular osteotomy (RAO) has been reported to be effective in improving symptoms and preventing osteoarthritis (OA) progression in patients with mild to severe develomental dysplasia of the hip (DDH). However, some patients develop secondary OA even when the preoperative joint space is normal; determining who will progress to OA is difficult. We evaluated whether the preoperative cartilage condition may predict OA progression following surgery using T2 mapping MRI. Methods. We reviewed 61 hips with early-stage OA in 61 patients who underwent RAO for DDH. They underwent preoperative and five-year postoperative radiological analysis of the hip. Those with a joint space narrowing of more than 1 mm were considered to have 'OA progression'. Preoperative assessment of articular cartilage was also performed using 3T MRI with the T2 mapping technique. The region of interest was defined as the weightbearing portion of the acetabulum and femoral head. Results. There were 16 patients with postoperative OA progression. The T2 values of the centre to the anterolateral region of the acetabulum and femoral head in the OA progression cases were significantly higher than those in patients without OA progression. The preoperative T2 values in those regions were positively correlated with the narrowed joint space width. The receiver operating characteristic analysis revealed that the T2 value of the central portion in the acetabulum provided excellent discrimination, with OA progression patients having an area under the curve of 0.858. Furthermore,
Aims. The practice of overlapping surgery has been increasing in the delivery of orthopaedic surgery, aiming to provide efficient, high-quality care. However, there are concerns about the safety of this practice. The purpose of this study was to examine the safety and efficacy of a model of partially overlapping surgery that we termed ‘swing room’ in the practice of primary total hip (THA) and knee arthroplasty (TKA). Methods. A retrospective review of prospectively collected data was carried out on patients who underwent primary THA and TKA between 2006 and 2017 in two academic centres. Cases were stratified as partially overlapping (swing room), in which the surgeon is in one operating room (OR) while the next patient is being prepared in another, or nonoverlapping surgery. The demographic details of the patients which were collected included operating time, length of stay (LOS), postoperative complications within six weeks of the procedure, unplanned hospital readmissions, and unplanned reoperations. Fisher's exact, Wilcoxon rank-sum tests, chi-squared tests, and
Aims. Vancouver type B periprosthetic femoral fractures (PFF) are challenging complications after total hip arthroplasty (THA), and some treatment controversies remain. The objectives of this study were: to evaluate the short-to-mid-term clinical outcomes after treatment of Vancouver type B PFF and to compare postoperative outcome in subgroups according to classifications and treatments; to report the clinical outcomes after conservative treatment; and to identify risk factors for postoperative complications in Vancouver type B PFF. Methods. A total of 97 consecutive PPFs (49 males and 48 females) were included with a mean age of 66 years (standard deviation (SD) 14.9). Of these, 86 patients were treated with surgery and 11 were treated conservatively. All living patients had a minimum two-year follow-up. Patient demographics details, fracture healing, functional scores, and complications were assessed. Clinical outcomes between internal fixation and revisions in patients with or without a stable femoral component were compared. Conservatively treated PPFs were evaluated in terms of mortality and healing status. A
Aims. We evaluated a large database with mechanical failure of a single uncemented modular femoral component, used in revision hip arthroplasty, as the end point and compared them to a control group treated with the same implant. Patient- and implant-specific risk factors for implant failure were analyzed. . Methods. All cases of a fractured uncemented modular revision femoral component from one manufacturer until April 2017 were identified and the total number of implants sold until April 2017 was used to calculate the fracture rate. The manufacturer provided data on patient demographics, time to failure, and implant details for all notified fractured devices. Patient- and implant-specific risk factors were evaluated using a logistic regression model with multiple imputations and compared to data from a previously published reference group, where no fractures had been observed. The results of a retrieval analysis of the fractured implants, performed by the manufacturer, were available for evaluation. Results. There were 113 recorded cases with fracture at the modular junction, resulting in a calculated fracture rate of 0.30% (113/37,600). The fracture rate of the implant without signs of improper use was 0.11% (41/37,600). In 79% (89/113) of cases with a failed implant, either a lateralized (high offset) neck segment, an extralong head, or the combination of both were used.
Aims. One-stage revision hip arthroplasty for periprosthetic joint infection (PJI) has several advantages; however, resection of the proximal femur might be necessary to achieve higher success rates. We investigated the risk factors for resection and re-revisions, and assessed complications and subsequent re-revisions. Methods. In this single-centre, case-control study, 57 patients who underwent one-stage revision arthroplasty for PJI of the hip and required resection of the proximal femur between 2009 and 2018 were identified. The control group consisted of 57 patients undergoing one-stage revision without bony resection.
Narrowing of the femoral neck after resurfacing arthroplasty of the hip has been described previously in both cemented and uncemented hip resurfacing. The natural history of narrowing of the femoral neck is unknown. We retrospectively measured the diameter of the femoral neck in a series of 163 Birmingham hip resurfacings in 163 patients up to a maximum of six years after operation to determine the extent and progression of narrowing. There were 105 men and 58 women with a mean age of 52 years (18 to 82). At a mean follow-up of five years, the mean Harris hip score was 94.8 (47 to 100) and the mean flexion of the hip 112.5° (80° to 160°). There was some narrowing of the femoral neck in 77% (125) of the patients reviewed, and in 27.6% (45) the narrowing exceeded 10% of the diameter of the neck. A multiple
We investigated the variables which determine the outcome after triple osteotomy of the pelvis for the treatment of congenital dysplasia of the hip. We reviewed 51 patients (61 hips) with a median age at operation of 23 years who were treated with a Tönnis triple osteotomy. The median follow-up was six years with a minimum of two years. Eight patients (eight hips) required a revision procedure. Of the remaining 53 hips, the results were good or excellent in 36 (68%) when evaluated according to the Harris hip score (median 90 points), and 33 patients (65%) were satisfied with the procedure.
Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI. We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.Aims
Methods
The risk factors for abnormal spinopelvic mobility (SPM), defined as an anterior rotation of the spinopelvic tilt (∆SPT) ≥ 20° in a flexed-seated position, have been described. The implication of pelvic incidence (PI) is unclear, and the concept of lumbar lordosis (LL) based on anatomical limits may be erroneous. The distribution of LL, including a unusual shape in patients with a high lordosis, a low pelvic incidence, and an anteverted pelvis seems more relevant. The clinical data of 311 consecutive patients who underwent total hip arthroplasty was retrospectively analyzed. We analyzed the different types of lumbar shapes that can present in patients to identify their potential associations with abnormal pelvic mobility, and we analyzed the potential risk factors associated with a ∆SPT ≥ 20° in the overall population.Aims
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The aims of this study were to validate the Forgotten Joint Score-12 (FJS-12) in the postoperative evaluation of periacetabular osteotomy (PAO), identify factors associated with joint awareness after PAO, and determine the FJS-12 threshold for patient-acceptable symptom state (PASS). Data from 686 patients (882 hips) with hip dysplasia who underwent transposition osteotomy of the acetabulum, a type of PAO, between 1998 and 2019 were reviewed. After screening the study included 442 patients (582 hips; response rate, 78%). Patients who completed a study questionnaire consisting of the visual analogue scale (VAS) for pain and satisfaction, FJS-12, and Hip disability and Osteoarthritis Outcome Score (HOOS) were included. The ceiling effects, internal consistency, convergent validity, and PASS thresholds of FJS-12 were investigated.Aims
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Type 2 diabetes mellitus (T2DM) impairs bone strength and is a significant risk factor for hip fracture, yet currently there is no reliable tool to assess this risk. Most risk stratification methods rely on bone mineral density, which is not impaired by diabetes, rendering current tests ineffective. CT-based finite element analysis (CTFEA) calculates the mechanical response of bone to load and uses the yield strain, which is reduced in T2DM patients, to measure bone strength. The purpose of this feasibility study was to examine whether CTFEA could be used to assess the hip fracture risk for T2DM patients. A retrospective cohort study was undertaken using autonomous CTFEA performed on existing abdominal or pelvic CT data comparing two groups of T2DM patients: a study group of 27 patients who had sustained a hip fracture within the year following the CT scan and a control group of 24 patients who did not have a hip fracture within one year. The main outcome of the CTFEA is a novel measure of hip bone strength termed the Hip Strength Score (HSS).Aims
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Although there is increasing legalization of the use of cannabis in the USA, few well-powered studies have evaluated the association between cannabis use disorder and outcomes following primary total hip arthroplasty (THA). Thus, the aim of this study was to determine whether patients who use cannabis and undergo primary THA have higher rates of in-hospital length of stay (LOS), medical complications, implant-related complications, and costs. Using an administrative database, patients with cannabis use disorder undergoing primary THA were matched to a control group in a 1:5 ratio by age, sex, and various medical comorbidities. This yielded 23,030 patients (3,842 in the study group matched with 19,188 in the control group). The variables which were studied included LOS, 90-day medical complications, two-year implant-related complications, and 90-day costs of care. Mann-Whitney U tests were used to compare LOS and costs. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of developing complications.Aims
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The primary aim was to determine the influence of COVID-19 on 30-day mortality following hip fracture. Secondary aims were to determine predictors of COVID-19 status on presentation and later in the admission; the rate of hospital acquired COVID-19; and the predictive value of negative swabs on admission. A nationwide multicentre retrospective cohort study was conducted of all patients presenting with a hip fracture to 17 Scottish centres in March and April 2020. Demographics, presentation blood tests, COVID-19 status, Nottingham Hip Fracture Score, management, length of stay, and 30-day mortality were recorded.Aims
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The aim of this study was to report the medium-term outcomes of impaction bone allograft and fibular grafting for osteonecrosis of the femoral head (ONFH) and to define the optimal indications. A total of 67 patients (77 hips) with ONFH were enrolled in a single centre retrospective review. Success of the procedure was assessed using the Harris Hip Score (HHS) and rate of revision to total hip arthroplasty (THA). Risk factors were studied, including age, aetiology, duration of hip pain, as well as two classification systems (Association Research Circulation Osseous (ARCO) and Japanese Investigation Committee (JIC) systems).Aims
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Aims. Dual mobility (DM) bearings are an attractive treatment option to obtain hip stability during challenging primary and revision total hip arthroplasty (THA) cases. The purpose of this study was to analyze data submitted to the American Joint Replacement Registry (AJRR) to characterize utilization trends of DM bearings in the USA. Methods. All primary and revision THA procedures reported to AJRR from 2012 to 2018 were analyzed. Patients of all ages were included and subdivided into DM and traditional bearing surface cohorts. Patient demographics, geographical region, hospital size, and teaching affiliation were assessed. Associations were determined by chi-squared