Methods

We combined the NJR dataset with polyethylene manufacturing properties as supplied by the manufacturers to sub-divide polyethylene into conventional (PE) and highly crosslinked (XLPE). Cause specific and overall reasons for revisions were analysed using Kaplan-Meier and multi-variate Cox proportional hazard regression survival analyses. The bearing surface analysis was repeated in patients undergoing THR under the age of 55.

Materials and Methods

We prospectively collected 3D plans generated from preoperative CTs of 30 consecutive THAs (17 left and 13 right hips), in 29 patients with OA, consisting of 16 males and 13 females (median age 68 years, range 46–83 years). A single CT-based planning system and cementless type of implant were used.

Post operatively, all patients had a CT scan which was reconstructed using state-of-the-art software solution: the plan and CT reconstruction models were

Outcome measures: 1) discrepancy between planned and achieved stem orientation angles Fig.2&3; 2) clinical outcome.

Methods

A custom drop tower was used to simulate surgical strikes seating acetabular components into synthetic bone. Strike velocity and drop mass were varied. Synthetic bone strain was measured using strain gauges and stability was assessed via push-out tests. Polar gap was measured using optical trackers.

Methods

In all, 27 THAs in 25 patients requiring THA with femoral shortening between 2012 and 2019 were assessed. Bilateral shortening was required in two patients. Subtrochanteric shortening was required in 14 out of 27 hips (51.9%) with aetiology other than DDH or septic arthritis. Vertical centre of rotation (VCOR), horizontal centre of rotation, offset, and functional outcome was calculated. The mean followup was 24.4 months (5 to 92 months).

Methods

In all, 134 consecutive hips that underwent periacetabular osteotomy were categorized using a validated software (Hip2Norm) into four categories of normal, lateral/global, anterior, or posterior. A total of 74 cases were selected for reliability analysis, and these included 44 dysplastic and 30 normal hips. A group of six blinded fellowship-trained raters, provided with the classification system, looked at these radiographs at two separate timepoints to classify the hips using standard radiological measurements. Thereafter, a consensus meeting was held where a modified flow diagram was devised, before a third reading by four raters using a separate set of 74 radiographs took place.

Methods

A questionnaire containing health resource use was completed at baseline and four months post-injury by patients or their carer. Completion rate and mean cost of each health resource item were assessed and sensitivity analysis was performed to derive a conservative estimate of the informal care cost. All costs are presented in 2017/18 pound sterling.

Methods

We retrospectively evaluated 17 patients (18 hips) who underwent the modified Dunn procedure for the treatment of slipped capital femoral epiphysis. Outcome measurement included standardized scores. Clinical assessment included ambulation, leg length discrepancy, and hip mobility. Radiographically, the quality of epiphyseal reduction was evaluated using the Southwick and Alpha-angles. Avascular necrosis, heterotopic ossifications, and osteoarthritis were documented at follow-up.

Methods

From 1996 to 2005, 49 children (52 hips) were treated for late-detected DDH. Their mean age was 13.3 months (3 to 33) at reduction. Prereduction skin traction was used for a mean of 11 days (0 to 27). Gentle closed reduction under general anaesthesia was attempted in all the hips. Concurrent pelvic osteotomy was not performed. The hips were evaluated at one, three and five years after reduction, at age eight to ten years, and at skeletal maturity. Mean age at the last follow-up was 15.7 years (13 to 21).

Methods

We retrospectively reviewed records of 183 primary uncemented THAs. Femoral morphology, including Dorr classification, canal bone ratio (CBR), canal flare index (CFI), and canal-calcar ratio (CCR), were calculated on preoperative radiographs. The canal fill ratio (CFR) was calculated at different levels relative to the lesser trochanter (LT) using immediate postoperative radiographs: P1, 2 cm above LT; P2, at LT; P3, 2 cm below LT; and D1, 7 cm below LT. At two years, radiological femoral component osseointegration was evaluated using the Engh score, and hip function using the Postel Merle d’Aubigné (PMA) and Oxford Hip Score (OHS).

Methods

A within-trial cost-utility analysis (CUA) will be conducted at four months postinjury from a health system (National Health Service and personal social services) perspective. Resource use pertaining to healthcare utilization (i.e. inpatient care, physiotherapy, social care, and home adaptations), and utility measures (quality-adjusted life years) will be collected at one and four months (primary outcome endpoint) postinjury; only treatment of complications will be captured at 12 months. Sensitivity analysis will be conducted to assess the robustness of the results.

Methods

Prospective cohort study using linked National Joint Registry (NJR) and manufacturer data. The primary endpoint was revision for aseptic loosening. Cox proportional hazard regression was the primary analytical approach. Manufacturing variables included resin type, crosslinking radiation dose, terminal sterilization method, terminal sterilization radiation dose, stabilization treatment, total radiation dose, packaging, and face asymmetry. Total radiation dose was further divided into G1 (no radiation), G2 (> 0 Mrad to < 5 Mrad), G3 (≥ 5 Mrad to < 10 Mrad), and G4 (≥ 10 Mrad).

Patients and Methods

A total of 28 patients (23 male, five female; mean age, 56 years (25 to 73)) awaiting Birmingham HRA volunteered for this prospective gait study, with an age-matched control group of 26 healthy adults (16 male, ten female; mean age, 56 years (33 to 84)). The Oxford Hip Score (OHS) and gait analysis using an instrumented treadmill were used preoperatively and more than two years postoperatively to measure the functional change attributable to the intervention.

Methods

Participants that underwent primary THA for hip osteoarthritis using lateral (n=21) or posterior (n=21) approaches, and healthy adults (n=21) were recruited for this cross-sectional study. Participants completed five walking trials. Surface electromyography captured gluteus medius activation. A 3-dimensional optical motion capture system measured frontal plane pelvic obliquity and lateral trunk lean angles. Participants performed maximum voluntary isometric contractions (MVIC) on a dynamometer to measure hip abductor torque. Characteristics from gait waveforms were identified using principal component analysis, and participant waveforms were scored against these characteristics to produce principal component scores. One-way analysis of variance and effect sizes (d) compared gait principal component scores and isometric hip abductor torque between groups.

Patients and Methods

A total of 525 patients (525 hips) underwent primary THA through posterior approach between 2009 and 2013. Fifty-four patients had mild chronic damage to the tendon. Forty-one patients had severe damage with major avulsion of the gluteus medius and minimus muscles.

Methods

This is a retrospective review of THA patient from July 2015-December 2017 was performed. Patient were stratified by insurance type (Medicare and commercial insurance) and whether care was provided before or after implementation of the CJR bundle. Patient age, gender, and BMI, as well as Elixhauser comorbidities and ASA scores were analyzed. Delivery of care variables including surgery duration, discharge disposition, length of stay, and direct hospital costs were compared before and after CJR implementation.

Methods

Patients undergoing primary THA during 2011–2017 were identified in the American College of Surgeons National Quality Improvement Program using CPT code 27130. Non-elective surgery and simultaneous bilateral THA procedures were excluded. Patients were classified as having discharged home or to not home locations. Trends in discharge destination, LOS, 30-day readmission, 30-day reoperation, and American Society of Anesthesiologists (ASA) classification were assessed using the Cochran-Armitage test.

Materials

Nineteen patients undergoing THA were recruited from the practices of 3 fellowship-trained hip surgeons. Each surgeon performed a single approach, DAA or PA. Enrolled patients underwent a preoperative MRI of the affected hip and two subsequent postoperative MRIs, averaging 9.6 and 24.3 weeks after surgery. Clinical evaluations were done by Harris Hip Score at each follow-up interval.

Methods

This was a multi-center retrospective study with 93 patients undergoing primary THA using a dual mobility cup with prior history of instrumented LSF. The primary outcome investigated was instability. Secondary variables investigated included number of levels fused, approach, length of stay, and other complications. The minimum follow-up time was 1 year since the majority of dislocations occur during first year following the primary THA.

Methods

Three experienced joint surgeons collected plain radiographs (AP and lateral) and CT/MR scans (n=40) from 72 cases of Vancouver A or B periprosthetic fractures performed over the period 2016–2018. We identified the mode of primary stem fixation and the Vancouver grade of the fracture (A, B1, B2 or B3). Two independent investigators examined all imaging studies and the intraoperative records and recorded: (i) and the location and distribution of the fracture surfaces, and (ii) the presence of incomplete cortical fractures that had initiated within the femoral cortex without completing propagation and (iii) the method of operative treatment. These data were analyzed to examine the incidence of fractures within more than one femoral zone and differences in the fracture patterns corresponding to each Vancouver class.

Methods

173 trochanteric fractures occurred in 171 patients, after all primary THAs performed from 1989–2017. Mean age at fracture was 64-years, with 65% being female. Mean follow-up was 7.6-years. Patient's radiographs and Harris Hip Scores (HHS) were recorded. There were 85 (49%) intraoperative and 88 postoperative fractures. Mean time from THA to fracture was 66 months for the postoperative group. 79 (46%) cases were fixed (68 intraoperative, 11 postoperative). Fixation was considered at the discretion of the surgeon.

Within the 88 postoperative fractures, 30 were associated with polyethylene wear and osteolysis. 77 were initially treated conservatively and 11 were immediately fixed (8 revisions due to osteolysis, and 3 fracture fixations due to disability associated to displacement >1cm). 19 of the 30 postoperative fractures associated with polyethylene wear and osteolysis, eventually underwent revision.

Methods

A 23-question survey was distributed via e-mail to active members of the Ruth Jackson Orthopaedic Society and a private social media group for women in orthopedics. Questions included demographics, current usage of PMMA, previous exposure during pregnancy and/or breastfeeding, and beliefs regarding current or future willingness of exposure. Additionally, questions were asked regarding PMMA training and whether beliefs influenced specialty choices.

Methods

We carried out an internet-based survey using a Google Forms platform posted on the PAO Facebook page and the Yahoo Hip Women group, comprising more than 1300 members. In a ten day enrollment period, 154 respondents completed the survey, which consisted of demographic information, plus multiple specific and open-ended questions

Methods

In this retrospective study, aspirate or tissue samples were collected in 23 revision and 19 primary hip arthroplasties for routine diagnostic workup for PJI and sent to the laboratory for NGS and PCR multiplex. Concordance along with statistical differences between diagnostic studies were calculated using Chi-squared test for categorical data.

Methods

Study groups included infected and non-infected (1) control, (2) systemic ceftriaxone (daily), (3) local tobramycin, (4) local doxycycline and (5) controlled release doxycycline. With IACUC approval, (10 rats/group; power =0.8), 50-μl, 10×4 CFU Staphylococcus aureus, slowly injecting into distal femoral medullary canal, reliably created joint infection. Antibiotic formulation was introduced locally into cavity and joint, pin was inserted, and tissues closed. After 4-weeks, serum, pin, bone and synovium were obtained. CFU/ml of bone and synovium were quantified using macrotiter method. SEM imaged biofilm on surface of pin, histopathology identified tissue response, liquid chromatography/mass spectrometry measured plasma antibiotic. Kruskal-Wallis one-way ANOVA compared groups.

Methods

In-vitro: Xen 36 S. aureus biofilm was grown on Ti-6Al-4V mouse tibial implants for 1 day or 5 days and subsequently exposed to growth media, 1000× minimal inhibitory concentration (MIC) Vancomycin, or 5× MIC PlySs2. Implants were sonicated and analyzed for Colony Forming Units (CFU).

In-vivo: A Ti-6Al-4V implant was inserted into the proximal tibia of C57BL/6J mice (n=21). All mice received 10⁴ CFU inoculation of Xen 36 S. aureus to the knee joint capsule and the infection was permitted 5 days to progress. On day 5 the mice were separated into three groups (n=7/group): (1) no further surgical intervention (control group), (2) irrigation and debridement (I&D) with saline, (3) I&D with 2mg/mL PlySs2. No implant-exchange was performed to mimic a debridement, antibiotic, and implant retention (DAIR) therapeutic strategy. All mice were sacrificed at day 10.

Methods

90 patients scheduled for hip or knee surgery were recruited for cultured biopsies. Four 3-mm dermal punch biopsies were collected after administration of anesthesia, but prior to delivery of perioperative antibiotics. Pre-biopsy skin prep consisted of a standardized pre-operative 2% chlorhexidine skin cleanse and an additional 70% isopropyl alcohol mechanical skin scrub immediately prior to biopsy collection. Two culture samples 10-cm apart were collected from a location approximating a standard direct anterior skin incision, and two samples 10-cm apart were collected from a location approximating a lateral skin incision (suitable for a posterior, direct-lateral or anterolateral surgical approach). Samples were cultured for two weeks.

Methods

This was a prospective-randomized controlled trial for patients undergoing primary THA through a direct anterior approach. Participants were randomized to be discharged on the same day as surgery, as outpatients, or on day one post-surgery, as inpatients, using a Zelen consent model. Adverse events were assessed, and participants completed self-reported cost questionnaires at two-, six- and 12-weeks post-surgery, and the WOMAC preoperatively and at 12-weeks post-surgery. We performed a cost analysis from health care payer (HCP) and societal perspectives.

Methods

Between 2012 and 2017, 105 primary DM THAs were performed using a one-piece acetabular shell, 28mm ceramic head, coupled with an E-HXLPE outer bearing via a standard posterior approach. Three patients refused follow-up after six months. 102 hips (92 patients) were available for review. The diagnosis was 99% OA. Average age was 65.7 years (33–90 years). 56% of patients were female. The most common femoral head size was 50mm (range, 44–60mm). The average thickness of the E-HXLPE outer bearing was 22.7mm (range, 16–32mm). Patients were followed at two months (baseline radiograph), six months, one, three, five, and seven years. Harris hip scores (HHS), UCLA activity score, and femoral head penetration (Martell method) were obtained at each visit beyond two months. Follow-up averaged 3 years (range, 1–7 years).

Methods

We reviewed all patients followed prospectively over a 15-year period (March 2000 to September 2015) who underwent total hip arthroplasty with one of three modern uncemented femoral stem designs. All of the stems were made of titanium (Ti₆Al₄V alloy) with a 12/14 taper design. We included only metal (cobalt chromium) on highly cross-linked polyethylene articulations. We evaluated age, gender, body mass index (BMI), femoral head size, head length, neck angle and offset as potential risk factors for all cause revision and revision excluding infection by univariate analysis. We performed a logistic regression analysis with odds ratios (OR) for each parameter for both all cause revision as well as with infection excluded. We used a p value of <0.05 as a level of significance.

Methods

A total of 67 MoP THA patients in two groups was investigated: 1) ALTR (n=38) on MARS MRI and 2) non-ALTR (n=29) on MARS MRI. All patients had highly cross-linked polyethylene liners with cobalt-chromium femoral heads with a single head-neck modularity. Parameters compared between groups included: acetabular component orientation, femoral neck shaft angle, radiographic measurement of medial and vertical femoral offsets, limb length discrepancy, component size, femoral head offset, implant type, femoral stem alloy and taper design.

Methods

The study used the Limited Data Set (LDS) from the Centers for Medicate and Medicaid Services (CMS) to identify all primary THA (DRG 469/470) performed in the US (excluding Maryland) during 2016. All cases were followed for one year after the original date of operation to create a database of readmissions after surgery. These data allowed for the determination of the 1-year incidence and type of reoperation, the timing of reoperation, the admitting diagnosis, hospital utilization, and total cost.

Materials and methods

The National Inpatient Sample, a representative sample of all hospital discharges within the United States, was used to determine the volume of revision total hip arthroplasty (THA) from 1993 to 2014. Procedures were identified by ICD-9 codes corresponding to revision THA. Annual incidence of revision THA was compared to annual incidence of primary THA to determine whether relative growth of revisions differed proportionally from the primary procedure. State-specific data was analyzed where available to develop geographic trend maps in the incidence of revision THA procedures using the estimated state population for years under review. Trends were also reviewed for hospital location (urban versus rural; teaching versus non-teaching) and total hospital charges. Analysis of trends was performed using linear regression models.

Material and methods

From 2004 to 2018, 257 patients (mean age: 67 years; range: 26–95) with a history of VTE underwent 277 primary, elective THAs procedures (128 right, 100 left, 9 single-stage bilateral, 20 staged bilateral) by two orthopaedic surgeons at a single institution. The patients had a history deep vein thrombosis (DVT) 186 (67%), pulmonary embolism (PE) 43 (15.5%), or both 48 (17.5%). Chemoprophylaxis included aspirin (38 patients) and anticoagulation (239 patients; Coumadin: 182, low-molecular-weight heparin: 3, clopidogrel: 1, rivaroxaban: 3, and a combination: 50). Forty eight patients (17.3%) had a vena cava filter at the time of surgery. Patients were followed for 120 days to detect complications, and for a year to detect mortality.

Methods

IC-21 ATCC peritoneal macrophages were cultured with growth medium of RPMI 1640 with 10%FBS, L-glutamine, and gentamicin. Interferon Gamma (IFNy) and Lipopolysaccharide (LPS) were used to induce activation of macrophages. Stainless Steel, CoCr, and Titanium disks cut, polished, and placed into a 96 well plate. Stainless steel testing included 6 groups: standard medium, 20,000 cells, 40,000 cells, 20,000 activated cells, 40,000 activated cells. CoCr and Ti testing included the following: medium, 40,000 cells, 20,000 activated cells, cells, no disk + 20,000 cells, no disk + 40,000 cells. After cells were attached to the surface, culture media was replaced and collected every 24 hours for stainless steel and every 12 hours for Ti and CoCr. ICP-MS, conducted at Brooks Applied Labs (Bothell, WA), was used to determine metal concentrations found in the supernatant.

Methods

We prospectively enrolled all patients undergoing primary THA and TKA. At one-year follow-up, patients were asked to complete a survey that asked about satisfaction with the and if they thought the visit was worthwhile. Surgeons also completed a survey which asked if any intervention was done, if any problems were diagnosed/avoided, and if the visit was worthwhile. Data was analyzed and compared between patients and surgeons, and was also compared to the need for any additional interventions

Methods

71 of 112 active and senior HS members (63%) responded to this 20-question survey.

Methods

A two-dimensional, axisymmetric FEA model representative of a CoCrMo femoral head taper and Ti6Al4V stem taper was created using median geometrical measurements taken from over 100 retrieved implants.³ Surface finish—micro-grooves—of the head/stem taper were modeled using a sinusoidal function with amplitude and period corresponding to retrieval measurements of micro-groove height and spacing, respectively. Two stem taper micro-groove geometries— “rough” and “smooth”—were modeled corresponding to the median and 5^th percentile height and spacing measurements from retrievals. All models had a 3' (0.05°), proximal-locked angular mismatch between the tapers.

To simulate implant assembly during surgery, multiple dynamic loads (4kN, 8kN, and 12kN) were applied to the femoral head taper in a sequence of one or three strikes. The input load profile (Figure 1) used for both cases was collected from surgeons assembling an experimental setup with a three-dimensional load sensor. Models were assembled and meshed in ABAQUS Standard (v 6.17) using four-node linear hexahedral, reduced integration elements. Friction was modeled between the stem and head taper using surface-to-surface formulation with penalty contact (µ=0.2). A total of 12 implicit, dynamic simulations (3 loads × 2 assembly sequences × 2 stem taper surface finishes) were run, with 2 static simulations at 4kN for evaluating inertial effects. Outcome variables included contact area, contact pressure, equivalent plastic strain, and pull-off force.

Methods

All patients who underwent an uncomplicated primary THA via a direct anterior approach with the short stem Taperloc Microplasty® (Zimmer Biomet, Warsaw, IN) implant between 2011 and 2015 were mailed a pain drawing questionnaire. Radiographs were reviewed at 1-year minimum to determine cortical thickness change from immediate post-op. Thigh pain was compared to DFCH as well as patient demographics and femoral stem size. 293 patients were included in the study

Methods

The electronic medical record at our institution was retrospectively reviewed for all primary, elective, unilateral THA between January 2016 and June 2018. THA recipients were categorized as either Hospital Ambulatory Clinic Centers (HACC) with Medicaid as the primary payer or private office patients with a non-Medicaid primary payer based on a previous visit to our institution's HACC within the 6-months prior to surgery. Only patients who had been operated on by a surgeon with at least 10 HACC and 10 private office patients were included.

Methods

Seventeen healthy older male golfers(62.2±8.8 years, handicap 8.7±4.9) free from orthopaedic injuries and surgeries volunteered for participation in this IRB-approved study. A 10-camera motion capture system recorded kinematics, and two force plates collected kinetic data. Participants performed eight shots using their own driver. Data processing was performed in Visual3D. The overall range of excursion and three-dimensional net joint moments normalized to body weight for the lead and trail hips were extracted.

Methods

We identified six cohorts of patients with 754 primary hips done between 1983 and 2007. With the exception of 81 Birmingham hip resurfacings (BHR), all femoral components were straight, extensively porous-coated cylindrical (EPC) stems (AML and Prodigy). All cups were porous coated. In addition to the BHRs, the bearing surfaces included 223 conventional polyethylene (CPE) in a non-modular shell, 114 CPE in a modular shell, 116 crosslinked polyethylene (XLPE), 130 metal-on-metal (MOM), and 90 ceramic-on-ceramic (COC). The mean follow-up for all hip replacements is 13.0±6.0 years. Kaplan-Meier survivorship using revision for any reason as an endpoint with log rank testing was used to evaluate differences among groups.

Methods

We assessed the long-term clinical outcomes of 1074 patients (1321 hips) who were implanted with hybrid Conserve^®Plus HRA, with 556 surgeries performed in patients younger than 50 years of age (average, 41.6 years) compared to 765 surgeries performed in patients 50 years or older (average, 58.1 years). 74% of the patients were male. There were no exclusion criteria. The <50 group had a larger proportion of dysplasia and hips operated during the first generation of surgical technique.

Methods

We performed a prospective validation study on 32 PAO's (28 patients) performed by a single academic surgeon. Preoperative standing radiographs, intraoperative fluoroscopic images, and postoperative standing radiographs were evaluated with lateral center edge angle (LCEA), acetabular index (AI), posterior wall sign (PWS), and anterior center edge angle (ACEA). Intraoperative fluoroscopy was adjusted to account for pelvic inclination. The fluoroscopic GRID was utilized in all cases (Phantom MSK Hip Preservation, OrthoGrid LLC, Salt Lake City, UT). Intraoperative fluoroscopic measurements were compared to preoperative and postoperative standing radiographs at 6 weeks using linear regression applied in MINITAB.

Methods

We reported patients who underwent labral debridement/focal labral excision during a period before the development of labral repair techniques. Patients with labral tears thought to be repairable with our current arthroscopic technique were compared with patients who underwent labral refixation. In 46 hips, the labrum was focally excised/debrided (group 1); in 54 hips, the labrum was refixed (group 2). Outcomes were measured with modified-Harris-Hip-Score (mHHS), Short Form-12 (SF-12), and a visual-analog-scale(VAS) for pain preoperatively and postoperatively.

Patients and Methods

Utilizing our total joint registry, we retrospectively identified 1215 THAs (1055 patients) performed with an uncemented dual-tapered stem from 1998 to 2009. Mean age was 55 years, 70% were male, and mean BMI was 30 kg/m². Mean follow-up was 10 years. Analysis included implant survivorship, clinical outcomes, and radiographic results.

Methods

A retrospective review of electronic health records was conducted at two academic medical centers and three community hospitals to identify adult patients who underwent THA for osteoarthritis between January 1^st, 2000 and August 1^st, 2018. Prolonged postoperative opioid prescriptions were defined as continuous opioid prescriptions after surgery to at least 90 days after surgery. Five machine learning algorithms were developed to predict this outcome and were assessed by discrimination, calibration, and decision curve analysis.

Methods

Six centers prospectively randomized 155 revisions to one of four regimens: 1g of intravenous (IV) TXA prior to incision, a double dose regimen of 1g IV TXA prior to incision and 1g IV TXA during wound closure, a combination of 1g IV TXA prior to incision and 1g intraoperative topical TXA, or three doses of 1950mg oral TXA administered 2 hours preoperatively, 6 hours postoperatively, and on the morning of postoperative day one. Randomization was based upon revision subgroups to ensure equivalent group distribution, including: femur only, acetabulum only, both component, explant/spacer, and second stage reimplantation. Patients undergoing an isolated modular exchange were excluded. An a priori power analysis (alpha = 0.05; beta = 0.80) determined 40 patients per group were required to identify a 1g/dL difference in postoperative hemoglobin reduction between groups. Per-protocol analysis involved an analysis of variance, Fisher's exact tests, and two one-sided t-tests for equivalence.

Methods

Four pristine MDM liners and shells were tested. Two liners were well-seated into their shells; two were canted at 6°. The liner-shell couples were assembled with a 2kN force after wetting the surfaces to promote a crevice environment conducive to corrosion. Couples were fixed in an electrochemical chamber at 40° inclination/20° anteversion to the load axis. The chamber was filled with phosphate buffered saline and setup as a three-electrode configuration: the shell as the working, a saturated calomel electrode as the reference, and a carbon rod as the counter electrode. A potentiostat held the system at −50mV throughout testing. After equilibration, couples underwent cyclic loading of increasing magnitudes from 100 to 3400N at 3 Hz. Fretting current was measured throughout, and the onset load for fretting was determined from the increase in average current.

Methods

78 patients who underwent THA were reviewed to quantify the variability in pre-operative spinopelvic mobility when two different seated positions (relaxed sitting v. pre-rise sitting) were used in the same patient.

Methods

We retrospectively identified all revision THAs with a Paprosky 3B defect and pelvic discontinuity between 2005 and 2017. Of the 162 patients, 32 were treated with distraction. The mean distraction achieved was 5mm (range, 3–8mm). In addition to distraction with a hemispherical cup, augments were utilized in 3 and cages in 19. The mean age at revision was 68 years with 75% female. Mean follow-up was 3 years.

Methods

We conducted a retrospective review of patients undergoing primary THA between May 2014 and December 2017 performed by a single surgeon at a tertiary care referral center. All patients were assessed preoperatively using an institutional RST and had a minimum of 90-day postoperative follow up. Patients were stratified by body mass index (BMI, kg/m²): non-obese (BMI < 30), obese (30–34), severely obese (35–39), morbidly obese (40–44), and super-obese (≥ 45). Primary outcomes were inpatient and 90-day complications. Continuous and binary parameters were analyzed by Kruskal-Wallis and Fisher exact tests. Logistic regression was additionally utilized to evaluate outcomes by BMI cohort.

Methods

Our institutional database was reviewed to identify patients 18–65 years of age who were diagnosed with atraumatic ONFH in our clinic between 1998–2018. The Association Research Circulation Osseous (ARCO) system was used to stage ONFH, based on available imaging. Patients with prior surgical treatment for ONFH were excluded.

Methods

We retrospectively reviewed the clinical and radiographic outcomes of 42 hips in 26 patients who underwent core decompression with BMAC for ON with a minimum of 1 year follow up. We evaluated pre-op visual analog pain scores (VAS), Steinberg class based on radiographs, as well as Kerboul angle as measured on MRI. Clinical outcomes were reported as change in VAS at final follow up, advancement in Steinberg classification based on radiographs at final follow up, or decision to proceed with THA.

Background

A total of 406,239 ONFH patients who were treated between 2009 and 2016 were identified from a nationwide database. Treatment procedures were extracted using ICD-9-CM and ICD-10-CM procedure codes. Annual rates of each of the above procedures were calculated and the trends in the procedure types were also evaluated. Chi-square tests were performed to compare the annual prevalence of each procedure. The mean annual prevalence over the 8-year study period was calculated for each procedure.

Background

Treatment of borderline acetabular dysplasia (BD) is controversial with some patients having primarily instability-based symptoms while others have impingement-based symptoms. The purpose of this study was to identify the most important patient characteristics influencing the diagnosis of instability vs. non-instability, develop a clinical score (Borderline Hip Instability Score, BHIS) to collectively characterize these factors and to externally validate BHIS in a multicenter cohort BD patients.

Methods

The prospective database on hip joint preservation identified 1,120 patients who have undergone FAO between January 2005-June 2019. Of these 164 patients (178 hips) have a minimum 10-year follow-up (range, 10–14). The database collects detailed information on patient demographics, clinical history, radiographic and cross sectional imaging findings, intraoperative findings (site and size of chondral lesion, labral tear, subchondral cyst, size of cam lesion, etc), and patient outcome using the modified HHS, SF-36, and UCLA activity score. Patients are contacted on an annual basis and the functional outcome instruments administered. Of 1,120 patients, 122 patients have been lost to follow-up.

Methods

Sixty-six consecutive hips in 64 patients (2 bilateral) undergoing endoscopic abductor tendon repair with a hollow core bioabsorbable suture anchor and having achieved two-year follow-up were prospectively assessed with modified Harris Hip Score (mHHS) and international Hip Outcome Tool (iHOT) scores. The MCID for patients undergoing hip arthroscopy has previously been determined as 8 for the mHHS and 13 for the iHOT. SCB has been determined as 20 for the mHHS and 28 for the iHOT. Subgroups were compared using the independent samples t-test.

Methods

All primary and revision THA procedures reported to AJRR from 2012–2018 were analyzed. Patients of all ages were included and subdivided into dual mobility and traditional bearing surface cohorts. Independent variables included patient demographics, geographic region, hospital size, and teaching affiliation. Associations were determined by chi-square analysis and a logistic regression was performed to assess the association between dual mobility and independent variables.

Methods

567 hips had primary modular dual mobility hip replacements (Biomet or Stryker) between 2016 and 2018. Post-operative radiographs were reviewed independently by two reviewers to identify malseating. Liners were considered malseated if there was a noticeable gap between the metal liner and acetabular shell(figure 1). All liners deemed to be malseated were independently assessed by 3 separate reviewers for confirmation.

Patients and Methods

A retrospective review was performed on 91 consecutive patients who had undergone primary THA by a single surgeon via a posterior approach in the lateral decubitus position. Of these, 41 patients had high quality standing AP pelvis radiographs preoperatively, at six weeks postoperatively, and at one year postoperatively available for analysis. Pelvic ratio was defined as the ratio between the vertical distance from the inferior sacroiliac (SI) joints to the superior pubic symphysis and the horizontal distance between the inferior SI joints. Apparent changes in the functional acetabular component position were determined from the change in pelvic ratio between the preoperative and one year postoperative standing AP pelvic radiograph. A change of at least five degrees was considered clinically meaningful.

Methods

Ten hip simulator constructs were assembled with 36-mm high-offset femoral heads, highly cross-linked polyethylene liners, and titanium stems. Five constructs used CoCr femoral heads and five used ceramic. Constructs were submerged in bovine serum (BS) and run for 1,000,000 cycles. Samples of BS were collected and evaluated for CoCr concentration. Various concentrations of CoCr were chosen for further assessment of cytotoxicity and growth impact on AMSCs and S. epidermidis and compared to inert SiO2.

Methods

We performed a systematic review of randomized control trials, cohort studies, and case series through May 2019, searching Embase, Medline via PubMed, and Cochrane Library for the concept of two-stage reimplantation for the treatment of hip and knee PJIs, yielding 464 unique citations for abstract review, of which 135 were reviewed in full. Our parameters of interest included: reinfection and mortality events following successful reimplantation, the timing of these events, and the microbiology of index and recurrent infections.

Material and methods

Remelted, single annealed and sequentially annealed retrieved HXLPE acetabular liners with in vivo times greater than 4.5 years were obtained from our implant retrieval laboratory. All retrieved liners underwent an identical sanitation and storage protocol. For mechanical testing, a total of 55 explants and 13 control liners were tested. Explant in vivo time ranged from 4.6 – 14.0 years and ex vivo time ranged from 0 – 11.6 years. Rim mechanical properties were tested by microindentation hardness testing using a Micromet II Vickers microhardness tester following ASTM standards. A subset of 16 explants with ex vivo time under one year along with five control liners were assessed for oxidation by FTIR, crystallinity by Raman spectroscopy, and evidence of microcracking by SEM.

Methods

A retrospective database analysis was conducted of 34,679 primary THAs performed between 2013–2017 in 29 hospitals in an integrated health system. Patient BMI was compared with operative time, LOS, complication rate, thirty-day readmission rate, inpatient cost, and post discharge disposition. Logistic regression was performed treating complications and readmission as outcomes and controlling for age.

Methods

A consecutive series of 174 THAs performed without TXA were compared to a consecutive series of 156 THAs performed with topical TXA. Procedures were performed by a single surgeon using identical perioperative medical and pain control protocols. Inpatient pain scores (VAS 0 to 10), opioid consumption (morphine equivalents, Meq), time to first opioid, and drop in hemoglobin (Hgb) were evaluated. Univariate analysis of topical TXA and 20 potential covariates of pain and blood loss was performed, followed by logistic and linear regression with p≤0.250.

Purpose/Hypthesis

The purpose of the current study was to establish and validate a method for identifying radiographic landmarks on the proximal femur that would reliably indicate that the femur was in the proper degree of rotation to represent the true offset from the head center to shaft center.

Methods

A retrospective review of prospectively collected data using an administrative database was carried out on patients who underwent primary unilateral total hip and total knee arthroplasty from 2006 to 2017 at two sites of one academic center staffed by four arthroplasty surgeons. All revisions and bilateral primary procedures were excluded. Cases were stratified as overlapping or non-overlapping. Overlapping was defined when a surgeon had access to two operating rooms with two teams, and non-overlapping was defined as when a surgeon only had access to a single operating room on a particular day. Patient demographic characteristics, operating room time, procedure time, length of stay, Postoperative complications within 30 days of the procedure, unplanned hospital readmissions, unplanned reoperations, and emergency department visits were collected. The Fisher's exact Wilcoxon rank-sum test and logistic regression analysis were used for statistical analysis.

Methods

Our IRB approved clinical database was queried for all primary total hip arthroplasties performed by the senior author from 1/1/2004 to 12/31/2016. All were performed via a modified direct lateral approach. Of these 1902 hips (1656 patients), 59 were identified in our medical records as patients who had a prior spine fusion or a spine fusion following THA. The extent of fusion was identified and reported. Radiographs were reviewed for acetabular position (abduction and anteversion) and leg length discrepancies. Records were reviewed and patients were contacted to determine if there were dislocations.

Methods

This is a cross-sectional, observational assessment of 88 consecutive metal-on-XLPE HRAs performed in 84 patients between 2015 and 2018 in three centres (three surgeons, including the designer surgeon). Mean follow-up is 1.6 years (0.7 to 3.9). Mean age at operation was 56 years (sd 11; 21 to 82), and 73% of implantations were in female patients. All patients were individually counselled, and a detailed informed consent was obtained prior to operation. Primary resurfacing was carried out in 85 hips, and three cases involved revision of previous MoM HRA. Clinical, radiological, and Oxford Hip Score (OHS) assessments were studied, along with implant survival.

Methods

A total of 168 patients were assessed in a retrospective observational study. Clinical information including age, sex, fracture side, American Society of Anesthesiologists (ASA) classification, tip-apex distance (TAD), fracture classification, reduction quality, blade position, BRQC, CRQC, bone quality, and the occurrence of mechanical complications were used in the statistical analysis.

Methods

Bupivacaine and tolfenamic acid were incorporated into UHMWPE via phase-separated compression molding. Drug release from the prepared samples was measured using high-performance liquid chromatography. Antibacterial studies of the obtained materials were conducted against methicillin-sensitive, and methicillin-resistant S. aureus, as well as S. epidermidis. Time-kill curves were obtained to characterize antimicrobial activity against planktonic bacteria. The dynamics of bacterial adhesion were assessed to characterize antibiofilm activity. Scanning electron microscopy (SEM) was used to visualize adherent bacteria. Anticolonizing activity of the tested materials was characterized using the “daughter cell” method as outlined elsewhere³. Cytotoxicity profile of drug-loaded UHMWPEs was evaluated using MG-63 osteoblast cell line.

Methods

This was a prospective RCT of 86 unilateral THA patients (M: 40, F: 48; mean age: 59.5 ± 10.6) randomized to either a porous-coated, modular metal-on-polyethylene (MoP) acetabular component (pore size 250µm, 45% mean volume porosity)(n=46) or a hydroxyapatite (HA) and titanium-coated monoblock shell with ceramic-on-ceramic(CoC) bearing (pore size 300µm, 48% mean volume porosity & 80nm HA coating thickness)(n=42). All sockets were under-reamed by 1 mm. Two-year radiographs and patient-reported outcomes (PROMs) were available.

Methods

Between January 2019 to April 2019, all patients undergoing primary THA were placed under a novel OSP (Table 1). Patient demographics, inpatient/surgical factors, and inpatient opiate administration events were collected. A historical 2:1 cohort was subsequently derived from patients undergoing THA between January 2018 to August 2018.

Opiate administration events collected from our EDW were converted into Morphine Milligram Equivalences (MMEs) and transformed into average MME's per patient per 24-hour interval. Nursing documented visual analog scale (VAS) pain scores were also queried and averaged per patient per 12-hour interval. To assess immediate postoperative functional status, the validated Activity Measure for Post-Acute Care (AM-PAC) Short Forms tool was utilized.

Methods

All patients with ADM and MDM implants underwent evaluation of metal ions (cobalt, chromium and titanium) at their one year follow-up appointment. Radiographic evaluation for acetabular polar gaps was performed. Elevated metal ions were determined using standard laboratory ranges. Differences in baseline demographics were assessed using the Mann Whitney-U test and Fishers's exact test. Differences in metal ions and implant type were compared using the Fisher's exact tests.

Methods

A cadaveric study was performed using 8 frozen, hemi-pelvises with cam-type deformity (alpha angle >55°) measured on CT scan and an intact labrum. Intraarticular pressure maps were produced for each specimen under the following conditions: 1) native cam deformity, 2) cam deformity with incomplete resection and 3) cam deformity with complete resection. A 5.5-mm burr was used to resect the lateral portion of the cam deformity to a depth of 3–4 mm. The specimen was placed in a custom designed jig in the MTS electromechanical test system to create pressure and area map measurements. In each condition, three biomechanical parameters were obtained including contact pressure, contact area and peak force within a region-of-interest (ROI). Repeated measurements were performed for three times in each condition and the average value of each parameter was used for statistical analysis. ANOVA was used to compare biomechanical parameters between three conditions.

Methods

The average cost per episode of care (EOC) was calculated using our institution's historical data. The target prices, projected savings or losses per EOC, and the projected annual savings for both BPCI and CJR were established and comparatively analyzed.

Methods

Following IRB approval, MVSL, MVISO and TRMVISO images were acquired for 93 hip arthroplasties (84 subjects). Images were reviewed by 2 radiologists to evaluate clinical and image quality features. Comparison of features between scanning sequences was assessed by mixed-effects ordinal logistic regression and odds ratios (OR). Inter/intra-rater agreement was determined using Gwet's agreement coefficient (AC).

Methods

We retrospectively identified 326 revision THAs where a non-constrained HXLPE liner was cemented into a well-fixed acetabular component. Mean age at revision THA was 63 years, with 50% being female. The most common indications for revision THA were wear and osteolysis (49%), aseptic femoral loosening (35%), and instability (8%). Mean follow-up was 10 years.

Methods

A retrospective review as performed on all procedures (except first stage exchange for infection) in which a Freedom® Constrained (Zimmer Biomet, Warsaw, IN) liner was used between December 2003 to November 2016. Patients with 2-year minimum follow-up or failure were included, yielding a cohort of 177 patients. Procedures were 130 revisions, 40 reimplantations following infection eradication, and 7 complex primaries. The constrained mechanism was implanted in 46 hips (26%) to treat active instability and 131 hips (74%) for increased risk of instability or intraoperative instability. Patients had on average 3.4 previous surgeries.

Methods

188 consecutive total hip arthroplasty (THA) surgeries performed by a single surgeon were prospectively studied. Pre-intervention assessment of the probable and preferred discharge disposition was performed using one of 5 tools (1) experienced surgical coordinator evaluation (2) Risk Assessment and Prediction Tool (RAPT); (3) Charlson Score; (4) ASA Score; and (5) Patient Self-Reported Health Status. Demographic characteristics, Visual Analogue Scale, QWB-7, SF-36, WOMAC, clinical scores were recorded before and after surgery. Correlation between final discharge disposition (home vs rehab) and its predictors was performed. Preoperative and postoperative outcomes were compared, p<0.05 was considered significant.

Methods

All primary THA procedures reported to the American Joint Replacement Registry from 2012–2018 with linked pre-operative and 1-year post-operative functional or anatomical PROMs were included. The achievement of minimal clinically-important difference (MCID) was calculated using the distribution method. Logistic regression models with covariate adjustment for patient demographics, American Society of Anesthesiologists (ASA) score, and body mass index (BMI) were constructed to identify associations with PROMs. Results were analyzed based on hospital size (small, medium and large) and teaching type (non-teaching, minor and major) based on the American Hospital Association Survey (2015).

Methods

Between 2011–2015, 7895 primary elective THA patients enrolled in the FORCE-TJR research consortium from over 200 surgeons in 28 states. Patients completed pre-op demographics, clinical risks, PROMs, and one-year outcomes. Over 95% completed pre-op PROMs; 83% post-op. Generic and hip specific (HOOS full and HOOS-12 sub-scores, and HOOS JR global) PROMs were compared.

Methods

The Harris Joint Registry was founded in 1969 and has since expanded to become the Partners Arthroplasty Registry (PAR). Today, the PAR captures data on total hip and total knee arthroplasties conducted at seven hospitals in Massachusetts. Over time, data has been sourced through independent collection at a single hospital, retrospective sourcing through the Research Patient Data Registry (RPDR), and currently through the Enterprise Data Warehouse (EDW). Various statistical methods analyzed changing trends of care provided to patients across affiliated institutions. PROMs collected in the PAR are the PROMIS Physical Function and Global Health Short Forms, the HOOS and KOOS. The registry is an associate member of ISAR and will incorporate the international implant library.

Methods

Clinical and hospital notes were collected for every patient undergoing a primary TJA. Human annotators reviewed a random training sample(n=400) and test sample(n=600) of notes from 6 different surgeons and manually abstracted historical, physical exam, operative, and outcomes data to create a gold standard dataset. Historical data collected included pain information and the various treatments tried (medications, injections, physical therapy). Physical exam information collected included ROM and the presence of deformity. Operative information included the angle of tibial slope, angle of tibial and femoral cuts, and patellar tracking for TKAs and approach and repair of external rotators for THAs. In addition, information on implant brand/type/size, sutures, and drains were collected for all TJAs. Finally, the occurrence of complications was collected. We then trained and tested our NLP system to automatically collect the respective variables. Finally, we assessed our automated approach by comparing system-generated findings against the gold standard.

Methods

All primary THAs at a single academic institution from 2010 to 2017 were analyzed through our institutional total joint registry. There were 7023 THAs including 3754 posterior, 1732 lateral, and 1537 direct anterior. Risk of dislocation was assessed against the competing risks of revision surgery and death as well as by individual patient and surgical factors including surgical approach. Risk of revision surgery was considered as a secondary outcome. Step-wise selection was utilized to develop multivariable models. Clinical outcomes were documented with the Harris Hip Score (HHS). Mean age was 63 years, 51% were female, and mean body mass index (BMI) was 30 kg/m². Minimum follow-up was 2 years.

Methods

We retrospectively identified 148 revision total hip arthroplasties (THAs) where a constrained liner of one design was cemented into a newly placed highly porous acetabular component fixed with supplemental screws (mean 5 screws). Mean age at revision THA was 69 years, with 68% being female. The most common indications for revision were two-stage re-implantation (33%), recurrent dislocation (30%), and aseptic loosening (22% acetabular; 9% acetabular/femoral component). Mean follow-up was 8 years.

Methods

We retrospectively analyzed 505 hips from 310 patients (141 men, 169 women; mean age 45.5 years (sd 14.9; 15 to 86)) diagnosed with ONFH and classified them using the Japanese Investigation Committee (JIC) classification. The JIC system includes four visualized types based on the location and size of osteonecrotic lesions on weightbearing surfaces (types A, B, C1, and C2) and the stage of ONFH. The collapse rate due to ONFH was calculated using Kaplan–Meier survival analysis, with radiological collapse/arthroplasty as endpoints.

Methods

A total of 18 synthetic femurs (Sawbones, Vashon Island, Washington) with comminuted pertrochanteric fractures were divided into three groups (n = 6 per group). Fracture fixation was performed using the Proximal Femoral Nail Antirotation (PFNA) implant (Synthes, Oberdorf, Switzerland; n = 6). Group 1 was subjected to unidirectional compression loading (600 N), with an elastomer (70A durometer) replacing loose fracture fragments to simulate surrounding soft-tissue tensioning. Group 2 was subjected to bidirectional loading (600 N compression loading, 120 N tensile loading), also with the elastomer replacing loose fracture fragments. Group 3 was subjected to bidirectional loading (600 N compression loading, 120 N tensile loading) without the elastomer. All constructs were tested at 2 Hz for 5000 cycles or until cut-out occurred. The medial migration distance (MMD) was recorded at the end of the testing cycles.

Patients and Methods

A total of 150 patients who were treated between February 2014 and July 2017 were included. Patients were allocated to undergo hemiarthroplasty using either an anterolateral or a direct lateral approach, and were followed for 12 months. The mean age of the patients was 81 years (69 to 90), and 109 were women (73%). Functional outcome measures, assessed by a physiotherapist blinded to allocation, and patient-reported outcome measures (PROMs) were collected postoperatively at three and 12 months.

Methods

A total of 24 specimens were manufactured by pouring cement (Simplex P Bone Cement; Stryker) into stainless steel moulds, with a central rod polished to Stryker Exeter V40 specifications. After cement curing, the rods were removed and eight specimens were allocated to each of three internal surface preparation groups: 1) burr; 2) OSCAR; and 3) no treatment. Internal holes were recemented, and each specimen was cut into 5 mm discs. Shear testing of discs was completed by a technician blinded to the original grouping, recording ultimate shear strengths. Scanning electron microscopy (SEM) was completed, inspecting surfaces of shear-tested specimens.

Patients and Methods

A prospective cohort study was conducted. Patients were recruited into three age groups: less than 65 years (n = 65), 65 to 74 years (n = 68), and 75 years and older (n = 67). There were 200 patients enrolled in the study, of whom 115 were female and 85 were male, with a mean age of 69.9 years (sd 9.5, 42 to 92). They were assessed preoperatively, and at three, 12 and, 24 months postoperatively. Stem migration was assessed using Einzel-Bild-Röntgen-Analyse (EBRA). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), Hip Disability and Osteoarthritis Outcome Score (HOOS), EuroQol-5 domains questionnaire (EQ-5D), short form-36 questionnaire (SF-36,) and patient satisfaction were used to assess outcome. The Lower Extremity Activity Scale (LEAS), Timed Up and Go (TUG) test, and activPAL monitor (energy expelled, time lying/standing/walking and step count) were used to assess activity. The BMD was assessed in Gruen and Charnley zones.

Study design and Methods

A sample size calculation showed 28 evaluations were required to reach a power of 85% (based on a kappa value of 0.4). The anterior-posterior pelvis and lateral hip radiographs of 30 hips, in 26 patients were evaluated by three Consultant Orthopaedic Surgeons using the classification detailed in table 1. A second evaluation, with the case order randomised, was performed after a minimum period of 1month. Randolph's free multi-rater Kappa co-efficient was used to assess for inter and intra- observer reliability and 95% confidence intervals were calculated.

Methods

We retrospectively reviewed the PAO's performed from 2014–2017, for symptomatic dysplasia in our unit (single-surgeon, minimum 1-year follow-up). All patients with adequate pelvic radiographs were included. Radiographic parameters of dysplasia were measured from pre- and post-operative AP pelvic radiographs using a validated software (SHIPS)¹. The degree of pubis displacement was classified according to our novel system. Cases were defined as those with evidence of iliopsoas-related pain post PAO (positive response to iliopsoas tendon-sheath steroid/local anaesthetic injection).

Patients/Materials and Methods

We retrospectively reviewed 16 patients (14 females) who underwent successful, bilateral, staged, PAOs (32 PAOs). These cases were matched for age and gender with 32 unilaterally dysplastic hips that underwent successful PAO for a similar degree of acetabular dysplasia as per pre-operative imaging. Supine and AP radiographs pre-PAO and at latest follow-up were used to measure centre-edge-angle (CEA) and Tönnis-angle (TA). PT was measured using two validated methods (Sacro-Femoral-Pubic (SFP) angle and Pubic-Symphysis to Sacro-Iliac (PS-SI) Index with excellent correlation (ρ=0.8, p<0.001).

Patients and Methods

A retrospective cohort study was performed involving 346 MoMHAs revised for histologically confirmed ARMD at two specialist centres (245=hip resurfacing, 101=total hip arthroplasty). Numerous preoperative (blood metal ions and imaging) and intraoperative (findings, and components removed/implanted) factors were used to predict poor outcomes. Poor outcomes were postoperative complications (including re-revisions), 90-day mortality, and poor Oxford Hip Scores (<27/48). Multivariable logistic regression models for predicting poor outcomes were developed using stepwise selection methods.

Methods

We identified 664,761 THRs in the NJR. The exposure was the unit in which the THR was implanted and the outcome all-cause revision. Net failure was estimated using Kaplan-Meier and adjusted analyses used flexible parametric survival analysis.

Methods

A total of 4126 consecutive THAs were reviewed for patients between 2006 and 2012 to allow for a minimum five-year follow-up. To determine the effects of the stem alignment on results, the hips were classified into 3 groups on the basis of stem alignment in initial postoperative anteroposterior radiographs. The alignment of the stem was defined as neutral, valgus (≥ 3° of lateral deviation), or varus (≥ 3° of medial deviation). The primary outcome was all cause revision with patient related outcomes assessed with Oxford hip score pre and post-operatively.