Competitive dancers represent a unique patient population in the setting of hip arthroplasty given the high degree of hip strength and mobility required by their profession. We sought to determine the clinical outcomes and ability to return to competitive dance after total hip arthroplasty (THA) or hip resurfacing arthroplasty (HRA) among competitive dancers. Active competitive dancers who underwent primary THA or HRA at a single institution with minimum one-year follow-up were included in the study. Primary outcomes included (1) the rate of return to competitive dance, (2) three PROMs (modified Harris Hip Score [mHHS], Hip Disability and Osteoarthritis Outcome Score for Joint Replacement [HOOS-JR], and Lower Extremity Activity Scale [LEAS]), and (3) post-operative complications. Forty-nine hips in 39 patients (mean age 56±13 years; 80% female) were included. Mean follow-up was 4.9±5.1 years. Thirty-seven THAs and 12 HRAs were performed. Ninety-six percent of patients returned to competitive dance activities post-operatively. With respect to PROMs, there were statistically significant improvements in mHHS, HOOS-JR, and LEAS from baseline to ≥ 1 year post-operatively. There were complications in 9/49 (18%) hips post-operatively, five (10%) of which required revision surgery. Active competitive dancers experienced significant improvements in functional outcome scores after THA or HRA, with a rate of return to competitive dance of 96%.
Dual mobility implants in total hip arthroplasty are designed to increase the functional head size, thus decreasing the potential for dislocation. Modular dual mobility (MDM) implants incorporate a metal liner (e.g. cobalt-chromium alloy) in a metal shell (e.g. titanium alloy), raising concern for mechanically assisted crevice corrosion at the modular liner-shell connection. We sought to examine fretting and corrosion on MDM liners, to analyze the corrosion products, and to examine histologically the periprosthetic tissues. A total of 60 retrieved liners were subjectively scored for fretting and corrosion. The corrosion products from the three most severely corroded implants were removed from the implant surface, imaged using scanning electron microscopy, and analyzed using Fourier-transform infrared spectroscopy.Aims
Methods
Due to the opioid epidemic in the USA, our service progressively decreased the number of opioid tablets prescribed at discharge after primary hip (THA) and knee (TKA) arthroplasty. The goal of this study was to analyze the effect on total morphine milligram equivalents (MMEs) prescribed and post-discharge opioid repeat prescriptions. We retrospectively reviewed 19,428 patients undergoing a primary THA or TKA between 1 February 2016 and 31 December 2019. Two reductions in the number of opioid tablets prescribed at discharge were implemented over this time; as such, we analyzed three periods (P1, P2, and P3) with different routine discharge MME (750, 520, and 320 MMEs, respectively). We investigated 90-day refill rates, refill MMEs, and whether discharge MMEs were associated with represcribing in a multivariate model.Aims
Methods
This combined clinical and in vitro study aimed to determine the incidence of liner malseating in modular dual mobility (MDM) constructs in primary total hip arthroplasties (THAs) from a large volume arthroplasty centre, and determine whether malseating increases the potential for fretting and corrosion at the modular metal interface in malseated MDM constructs using a simulated corrosion chamber. For the clinical arm of the study, observers independently reviewed postoperative radiographs of 551 primary THAs using MDM constructs from a single manufacturer over a three-year period, to identify the incidence of MDM liner-shell malseating. Multivariable logistic regression analysis was performed to identify risk factors including age, sex, body mass index (BMI), cup design, cup size, and the MDM case volume of the surgeon. For the in vitro arm, six pristine MDM implants with cobalt-chrome liners were tested in a simulated corrosion chamber. Three were well-seated and three were malseated with 6° of canting. The liner-shell couples underwent cyclic loading of increasing magnitudes. Fretting current was measured throughout testing and the onset of fretting load was determined by analyzing the increase in average current.Aims
Methods
The purpose of this multicenter, randomized clinical trial was to determine the optimal dosing regimen of tranexamic acid (TXA) to minimize perioperative blood loss for revision total hip arthroplasty (THA). 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 Background
Methods
MDM implants can enhance stability in total hip replacement (THR), but complications include malseated liners and corrosion between the cobalt-chrome liner and titanium acetabular shell increased systemic metal ion levels. The liner-shell junction has the potential for fretting corrosion, and the corrosion could be exacerbated in malseated liners. We determined the potential for fretting corrosion in malseated versus well-seated liners using a mechanical electrochemical corrosion chamber. 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.Introduction
Methods
Enhanced stability using dual mobility has been demonstrated but concerns about potential for corrosion in modular versions have been raised. Case reports of corrosion with malseated inserts have heightened concerns over this modularity. Some have claimed that malseating is rare, the true frequency is unknown. The purpose of our investigation was to determine the incidence of liner malseating in dual mobility implants at our institution. 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.Introduction
Methods
Failure of metal on metal (MOM) total hip arthroplasty (THA) and resurfacing arthroplasty (HRA) due to development of adverse local tissue reaction (ALTRs) is a significant problem. The prevalence of ALTRs in asymptomatic MOM arthroplasty patients is highly variable. The purpose of this prospective, longitudinal study was to: 1) determine MRI ALTR prevalence in patients with HRA; 2) determine if patients with HRA have a greater rate of MRI ALTRs compared to control patients with ceramic on poly (COP) THA; and 3) evaluate changes in patient reported outcomes between these implant designs. Following IRB approval with informed consent, self-reported asymptomatic primary COP and HRA patients greater than one year post arthroplasty were evaluated with 4 annual (TP1–4) MRIs using a standardized protocol and serum ion level testing. Morphologic and susceptibility reduced images were acquired for each hip and evaluated for synovial thickness, volume, capsule dehiscence and the presence of ALTR. Patient reported outcomes were evaluated by Hip Disability and Osteoarthritis Outcome Scores (HOOS). Analyses were performed to detect differences of synovial thickness and volume, and HOOS subgroups between and within bearing surfaces at each time point and over time, and to compare the time to and the risk of developing MRI ALTR. Analyses were adjusted for age, gender, and length of implantation.Introduction
Methods
The aim of this study was to evaluate the accuracy of implant placement when using robotic assistance during total hip arthroplasty (THA). A total of 20 patients underwent a planned THA using preoperative CT scans and robotic-assisted software. There were nine men and 11 women (n = 20 hips) with a mean age of 60.8 years (Aims
Patients and Methods
The aims of this study were to measure sagittal standing and sitting lumbar-pelvic-femoral alignment in patients before and following total hip arthroplasty (THA), and to consider what preoperative factors may influence a change in postoperative pelvic position. A total of 161 patients were considered for inclusion. Patients had a mean age of the remaining 61 years (Aims
Patients and Methods
There are many guidelines that help direct the management of
patients with metal-on-metal (MOM) hip arthroplasties. We have undertaken
a study to compare the management of patients with MOM hip arthroplasties in
different countries. Six international tertiary referral orthopaedic centres were
invited to participate by organising a multi-disciplinary team (MDT)
meeting, consisting of two or more revision hip arthroplasty surgeons
and a musculoskeletal radiologist. A full clinical dataset including
history, blood tests and imaging for ten patients was sent to each
unit, for discussion and treatment planning. Differences in the
interpretation of findings, management decisions and rationale for
decisions were compared using quantitative and qualitative methods.Aims
Methods
