Introduction

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.

Introduction

Perioperative hospital adverse events are an issue that every surgeon endeavors to avoid and minimize as much as possible. Even “minor events” such as fever or tachycardia may lead to significant costs due to workup tests, inter-consultations, and/or increased hospital stay. The objective of this study was compare perioperative outcomes (hospital length of stay [LOS], discharge disposition), rates of in-hospital adverse events and transfusion, and postoperative readmission and reoperation rates for simultaneous and staged bilateral direct anterior total hip arthroplasty (DA-THA) patients.

Introduction

Periprosthetic osteolysis (PPO) gradually became the single dominant late failure mechanism of total hip replacements. It afflicted 1 million patients worldwide, leading to countless, difficult revision operations. The widespread adoption of highly cross-linked polyethylene (XLPE) drastically reduced that disease. But going beyond that remarkable reversal, two further substantial consequences have resulted: A) a major reduction in revision operations and B) a major reduction in aggregate costs of total replacement surgery. This paper assembles data on the decrease in revision rates and uses them to estimate the massive reduction in total hip surgery costs.

Introduction

Historically, the most common indications for re-revision of a total hip arthroplasty (THA) have been aseptic loosening, instability, infection, and peri-prosthetic fracture. As revision implants and techniques have evolved and improved, understanding why contemporary revision THAs fail is important to direct further improvement and innovation. As such, the goals of this study were to determine the implant survivorship of contemporary revision THAs, as well as the most common indications for re-revision.

Introduction

During revision total hip arthroplasty, successful treatment of acetabular bone loss with an associated chronic pelvic discontinuity is dependent upon the remaining bone stock, stability of the construct, potential for biologic fixation, and healing of the discontinuity. Several techniques have been described for the treatment of this clinical entity; the authors recommend the use of acetabular distraction technique in conjunction with a jumbo cup with or without augments.

The authors recently evaluated the minimum two-year follow-up of acetabular distraction technique for the treatment of chronic pelvic discontinuity. In the process, a chronic pelvic discontinuity classification was created based on the type of reconstruction required. The purpose of this study is to introduce the initial observations of this novel classification system.

Introduction

Ascertaining the etiology of hip pain in young patients can be challenging. Osteoid osteoma about the hip has only been described in case reports and small case series in this sub-population. This study assessed the clinical course, radiologic findings, and treatment approaches in a large series of pediatric osteoid osteoma cases about the hip. Potential diagnostic and treatment pitfalls were identified.

Introduction

Hip abductor tendon tears have been referred to as “rotator cuff tears of the hip,” and are a recognized etiology for persistent, often progressive, lateral hip pain, weakness, and limp. Multiple repair techniques and salvage procedures for abductor tendon tears have been reported in the literature; however, re-tear remains a frequent complication following surgical repair. This study compares the short-term outcomes of open abductor tendon repairs with decortication and suture fixation (DSF) compared to a modified technique repair into a bone trough (BT), to determine best surgical results for large abductor tendon avulsions. Additionally, surgical treatment of small tears versus large tears was examined.

Introduction

Modularity in femoral stem designs allow surgeons to independently control leg length, offset, and femoral version in revision or complex primary THA cases. Initial enthusiasm in these modular stems has been tempered by recognition of modular junction failures. This study evaluates mean 5-year clinical results and survival rates of a 3-part titanium alloy modular femoral implant with unique taper geometries and a metaphyseal plasma spray surface. The current results are presented after pre-market independent fatigue testing performed by Orthopaedic Laboratory (Greenwald) and previously published early clinical results in 2006. Low plasticity burnishing (LPB) was added in 2005 to further strengthen the neck metaphyseal modular junction. The modular stem component is a polished cylindrical splined clothespin design. Our hypothesis is that these unique modular junctions succeed in offering the advantages of modularity without failure at this midterm follow-up period.

Aims

The aim of this study was to evaluate the accuracy of implant placement when using robotic assistance during total hip arthroplasty (THA).

Introduction

In 2010, a widely used metal-on-metal hip implant was voluntarily recalled from the market by the manufacturer. Our lab performed detailed retrieval analysis of 548 of the explanted devices and 165 periprosthetic tissue specimens. We reported a high degree of variability in the multiple measurements that we performed on the components, including volumetric wear.

Other studies using semi-quantitative tissue grading methods to describe the histology of the periprosthetic tissues from metal-on-metal hips have looked for relationships between component wear and histological features. Grammatopoulos et al found higher ALVAL scores in 45 hip resurfacing patients with pseudotumors compared to 11 without pseudotumors and a moderately positive correlation between wear and the histological rankings for tissue necrosis and lymphocytic response.

We examined correlations between the component wear measurements from retrieval analysis and the tissue features in this large group of one metal-on-metal hip design.

The statements contained in this document are solely those of the authors and do not necessarily reflect the views or policies of CMS. The authors assume responsibility for the accuracy and completeness of the information contained in this document.

Introduction

Previous studies have indicated that prolonged surgical time may lead to higher rates of infection following total hip arthroplasty (THA). The purpose of this study was to evaluate the influence of surgical time on 30-day complications following THA and to determine if there was a time interval associated with worse outcomes.

Background

Much effort has been aimed at strategies for patient optimization, perioperative standards of care, and postoperative risk stratification to reduce the incidence of SSI. Examples include, newer dressing modalities, antibiotic-impregnated bone cement, intra-wound powdered antibiotics, as well as novel suture types and techniques, all of which have shown great potential. However, the question remains as to whether these changes in practice have led to lower overall infections over the past few years. Therefore, the purpose of this study was to track the annual rates and trends of: 1) overall; 2) deep; and 3) superficial SSI following total hip arthroplasty (THA) using the most recent data (2012 to 2016) from a large nationwide database.

Background

Structural bone allografts are an established treatment method for long-bone structural defects arising from such conditions as trauma, sarcoma, and osteolysis following total joint replacement. However, the quality of structural bone allografts is difficult to non-destructively assess prior to use. The functional lifetime of structural allografts depend on their ability to resist cyclic loading, which can lead to fracture even at stress levels well below the yield strength. Because allograft bone has limited capacity for remodeling, optimizing allograft selection for bone quality could decrease long-term fracture risk. Raman spectroscopy biomarkers can non-destructively assess the three primary components of bone (collagen, mineral, and water), and may predict the resistance of donor bone allografts to fracture from cyclic loads.

The purpose of this study was to prospectively assess the ability of Raman biomarkers to predict number of cycles to fracture (“cyclic fatigue life”) of human allograft cortical bone.

Introduction

Cephalomedullary nails (CMN) are commonly used for the treatment of intertrochanteric (IT) hip fractures. Total hip arthroplasty (THA) is commonly used as a salvage procedure for failed IT hip fractures that progress to post-traumatic arthritis. This study analyzed the complications of THA following treatment of failed IT hip fractures with cephalomedullary nails.

Introduction

Patients under the age of 50 who undergo a total hip arthroplasty (THA) are at high risk for wear-related complications due to their higher activity level. Previous studies have shown that highly crosslinked polyethylene (HXLPE) is more durable with no evidence of loosening compared to conventional polyethylene due to its improved wear characteristics. Unfortunately, there are few studies with long term follow-up of HXLPE in this patient population. The purpose of this study was to evaluate two questions related to this population of patients undergoing THA. First, what were the clinical outcomes for HXLPE in patients 50 years or younger at an average follow-up of 15 years? Second, was osteolysis observed in any of these hips?

Introduction

The infection rate after total joint arthroplasty (TJA) has been shown to be 1–2% in multiple series and registry data. Irrigation, debridement, and polyethylene exchange (IDPE) is a common first line treatment in many cases of acute prosthetic joint infection (PJI). The reinfection rate in open IDPE procedures is variable with studies showing reinfection rates of 10–70% depending on various patient and microbial factors. Our pilot study aimed to determine if the bacterial load in infected total joints was sufficiently reduced by IDPE to allow for the use of post-debridement cultures as an independent marker of procedural success.

Background

Despite growing interest in direct anterior approach total hip arthroplasty, perioperative femoral fracture and early aseptic loosening are increasingly recognized complications. Previous research has documented the role of surgeon experience in association with these femoral complications. The purpose of this study was to explore the relationship between femoral component design and early periprosthetic femoral complications.

Introduction

Modular dual-mobility constructs reduce the risk of dislocation after total hip arthroplasty (THA). However, questions about metal ions from the cobalt-chrome (CoCr) liner persist, and are particularly germane to patients being revised for adverse local tissue reactions (ALTR) to metal. We determined the mid-term serum Co and Cr levels after modular dual-mobilities used in revision and complex primary THAs, and specifically included patients revised for ALTR.

Introduction

Opioids are an important component of multimodal analgesia, but improper utilization places patients at risk for overdose and addiction. The purpose of this randomized controlled trial is to determine whether the quantity of opioid pills prescribed at discharge is associated with the total amount of opioids consumed or unused by patients after total hip (THA) and knee (TKA) arthroplasty.

Introduction

Many pharmacologic agents have been used for venous thromboembolism (VTE) prophylaxis after elective total hip arthroplasty (THA). Rivaroxaban was the first novel oral anticoagulant approved for THA patients, but its actual efficacy and safety in clinical practice, beyond randomized trials, is unknown.

Background

Fully constrained liners are used to treat recurrent dislocations or patients at high risk after total hip replacements. However, they can cause significant morbidities including recurrent dislocations, infections, aseptic loosening and fractures. We examine long term results of 111 patients with tripolar constrained components to assess their redislocation and failure rate.

Background

High complication rates and poor outcomes have been widely reported in patients undergoing revision of large head metal-on-metal arthroplasty. A previous study from our center showed high rates of dislocation, nerve injury, early cup loosening and pseudotumor recurrence. After noting these issues, we implemented the following changes in surgical protocol in all large head MOM revisions: 1. Use of highly porous shells in all cases 2. Use of largest femoral head possible 3. Low threshold for use of dual mobility and constrained liners when abductors affected or absent posterior capsule 4. Use of ceramic head with titanium sleeve in all cases 5. Partial resection of pseudotumor adjacent to sciatic and femoral nerves.

Introduction

The American Joint Replacement Registry (AJRR) was created to capture total hip (THA) and total knee arthroplasty (TKA) procedural data in order to conduct implant-specific survivorship analyses, produce risk-adjusted patient outcome data, and provide hospitals and surgeons with quality benchmarks. The purpose of this study is to compare early reports from the AJRR to other national registries to identify similarities and differences in surgeon practice and potential topics for future analysis.

Introduction

Deaths due to overdose involving opioids have nearly quadrupled in USA in the last 20 years. Several published studies have shown that preoperative opioid use independently predicts perioperative complications in total joint arthroplasty. Our objectives were to (1) assess preoperative opioid consumption in patients undergoing total hip arthroplasty (THA) and (2) to determine how preoperative opioid use affects patient oriented outcomes (POO's) and hip scores before and after THA.

Introduction

Ceramic heads are used in hip revision surgery to mitigate corrosion concerns. Manufacturers recommend using a pristine titanium sleeve in conjunction with a well-fixed metal stem to prevent early failure of the ceramic head. However, the influence of impact force, head size, and sleeve offset on pull-off strength and seating displacement of a revision head assembly is not fully understood. Therefore, the purpose of this study was to investigate the pull-off strength and displacement of commercially available revision ceramic heads and titanium taper sleeve offsets (BIOLOX OPTION, CeramTec GmbH, Plochingen, Germany) while covering a range of clinically relevant impaction forces.

Aims

There are limited published data detailing the volumetric material loss from tapers of conventional metal-on-polyethylene (MoP) total hip arthroplasties (THAs). Our aim was to address this by comparing the taper wear rates measured in an explanted cohort of the widely used Exeter THA with those measured in a group of metal-on-metal (MoM) THAs.

Aims

The purpose of this study was to evaluate spinopelvic mechanics from standing and sitting positions in subjects with and without femoroacetabular impingement (FAI). We hypothesize that FAI patients will experience less flexion at the lumbar spine and more flexion at the hip whilst changing from standing to sitting positions than subjects without FAI. This increase in hip flexion may contribute to symptomatology in FAI.

Introduction

Bundle payment models have clinical and economic impacts on providers. Despite efforts made to improve care, experience has shown that a few episodes with costs well above a target (bundle busters) can reduce or negate positive performances. The purpose of this study was to identify both the primary episode drivers of cost and patient factors that led to episodes above target.

Introduction

The Comprehensive Care for Joint Replacement (CJR) model for total hip arthroplasty (THA) involves a target reimbursement set by the Center for Medicare and Medicaid Services (CMS). Many patients exceed these targets, but predicting risk for incurring these excess costs remains challenging, and we hypothesized that select patient characteristics would adequately predict CJR cost overruns.

Purpose

Obesity has previously been demonstrated to be an independent risk factor for increased complications following total hip (THA) and total knee arthroplasty (TKA). The purpose of this study was to compare the effects of obesity and BMI to determine whether the magnitude of the effect was similar for both procedures.

Background

Routine closed suction drainage and postoperative laboratory studies have long been tenets of most TJA protocols. However, recent literature has called into question whether either is necessary with modern outpatient TJA clinical pathways.

Introduction

Porous surfaces developed over the past decades have been shown to promote tissue ingrowth. Hydroxyapatite (HA) coatings have been added to these porous coatings in an attempt to further augment bone ingrowth. The development of additive manufacturing techniques has allowed for precision in building these complex porous structures. The effect of supplemental HA coatings on these new surfaces is unclear. The purpose of this study is to evaluate the biological fixation of a novel 3D printed porous implant in a canine model. In addition, we evaluated the effect of different HA coatings on this 3D printed implant.

Introduction

Manual chart review is labor-intensive and requires specialized knowledge possessed by highly-trained medical professionals. The cost and infrastructure challenges required to implement this is prohibitive for most hospitals. Natural language processing (NLP) tools are distinctive in their ability to extract critical information from raw text in the electronic health records (EHR). As a simple proof-of-concept, for the potential application of this technology, we examined its ability to discriminate between a binary classification (periprosthetic fracture [PPFFx] vs. no PPFFx) followed by a more complex classification of the same problem (Vancouver).

Introduction

Increasingly, patients with bilateral hip arthritis wish to undergo staged total hip arthroplasty. With the rise in demand for arthroplasty perioperative risk assessment and counseling is critical for shared decision making; however, it is unknown if complications that occur after a unilateral hip arthroplasty predict complications following surgery of the contralateral hip.

Introduction

Historically, US arthroplasty revision rates are based on CMS data that cannot verify initial surgery date in patients under 65 years or laterality of revision. We calculated US one-year revision rates for primary total hip replacement (THR) using a representative cohort. Reasons for revision were documented.

Introduction

Complications can be defined as preventable, potentially preventable, or non-preventable. While often discussed, there are virtually no data whether or not the most common causes of revision total hip arthroplasty (THA) are preventable or not. The goal of this study was to identify and report preventable causes of revision THA within 5 years of the index THA.

Total hip arthroplasty (THA) continues moving to the outpatient arena, and may be feasible for some conversion and revision scenarios. Controversy surrounds appropriate patient selection. The purpose of this study is to report complications associated with outpatient revision and conversion THA, and to determine if comorbidities are associated with complications or overnight stay.

From June 2013 through March 2018, 43 patients (44 hips) underwent conversion (n=9) or revision (n=35) THA at a free-standing ambulatory surgery center. Mean patient age was 58.4 years, and 52% of patients were male. Conversion procedures were failed fracture fixation with retained hardware and all involved both femoral and acetabular replacement. Revision procedures involved head only in one, head and liner in 20, cup and head in 8, stem only in one, stem and liner in 4, and full revision in one.

Forty-one (93%) were discharged same day without incident, none required transfer to acute facility, and 3 required overnight stay with 2 of these for convenience and only one for a medical reason, urinary retention. Three patients with early superficial infection, including 2 diagnosed by positive intraoperative cultures, were successfully treated with oral antibiotics. There were no major complications, readmissions, or subsequent surgeries within 90 days. One or more major comorbidities were present in 15 patients (34%) including 1 valvular disease, 7 arrhythmia, 2 thromboembolism history, 3 obstructive sleep apnea, 3 chronic obstructive pulmonary disease, 2 asthma, 4 frequent urination, and 1 renal disease. The single patient who stayed overnight for a medical reason had no major medical comorbidities.

Outpatient arthroplasty, including revision THA in some scenarios, is safe for many patients. Presence of medical comorbidities was not associated with risk of complications. The paradigm change of patient education, medical optimization, and a multimodal program to mitigate risk of blood loss and reduce need for narcotics facilitates performing arthroplasty safely in an outpatient setting.

Introduction

Tranexamic acid (TXA) has been shown to significantly reduce transfusion rates in primary total hip arthroplasties (THAs), but data is limited in the revision setting. The purpose of the current study was to compare the rate of blood transfusions and symptomatic venous thromboembolic events (VTEs) in a large cohort of revision THAs treated with or without IV TXA.

Purpose

Patients may present with concurrent symptomatic hip and spine problems, with surgical treatment indicated for both. Controversy exists over which procedure, total hip arthroplasty (THA) or lumbar spine procedure, should be performed first, and does the surgeon's area of expertise influence the choice.

Introduction

There has been a renewed interest in the surgical approach used for total hip arthroplasty (THA). Risk factors for periprosthetic joint infection (PJI) have been well studied over the past decade, yet PJI remains one of the most devastating complications following THA. We studied the impact of direct anterior (DA) versus non-direct anterior (NA) surgical approaches on PJI, and examined the impact of new perioperative protocols on PJI rates following all surgical approaches at a single institution.

Introduction

Studies are being done comparing 1-stage vs. 2-stage protocols for PJI. 1-stage protocols take an extended period of time requiring 2 separate preps and sets of instruments in order to ensure optimal sterility. While intraoperative service time is one part of the reimbursement algorithm, reimbursement has lagged behind for single stage treatment. If 1-stage results are acceptable, but not reimbursed appropriately, surgeons may be discouraged from managing PJI in a 1-stage fashion. We ask, “What is the reimbursement and intraoperative service time for 1-stage procedures compared to primary surgery?”

The increasing infection burden after hip arthroplasty has seen a growth of two-stage exchange and the use of increasingly powerful antibiotics at the time of this procedure. We have seen an increased number of failed two-stage revisions over the past decade. This study was aimed at clarifying the outcome of failed two-stage exchange arthroplasty after periprosthetic hip infection.

We identified forty-two patients who had undergone at least one prior two-stage revision hip arthroplasty for periprosthetic infection between 2000 and 2012. These patients were referred to our center and treated with a further two-stage exchange. They have been analyzed with a minimum two-year follow-up.

Control of infection at two-year follow-up was seen in 57% of patients. In 43% of patients there are still ongoing issues that either required further surgery or ongoing antibiotic suppression.

A regression analysis was undertaken which suggested that the immunocompromised host and polymicrobial infection were the greatest predictors of failure. The number of previous interventions, the organism involved and the duration of antibiotic therapy after the initial two-stage revision were not linked to the ultimate outcome.

The failure rate of repeat revision two-stage exchange is high and novel methods of treatment including host optimization, immunomodulation, longer interval periods, novel antimicrobial methods and more powerful antibiotic therapies should be investigated.

Introduction

Iliopsoas tendonitis after total hip arthroplasty (THA) can be a considerable cause of pain and patient dissatisfaction. The optimal cup position to avoid iliopsoas tendonitis has not been clearly established. Implant designs have also been developed with an anterior recess to avoid iliopsoas impingement. The purpose of this cadaveric study was to determine the effect of cup position and implant design on iliopsoas impingement.

Aims

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.

Aims

This study aims to: determine the difference in pelvic position that occurs between surgery and radiographic, supine, postoperative assessment; examine how the difference in pelvic position influences subsequent component orientation; and establish whether differences in pelvic position, and thereafter component orientation, exist between total hip arthroplasties (THAs) performed in the supine versus the lateral decubitus positions.

Introduction

Malposition of the acetabular component in total hip arthroplasty (THA) is linked to multiple adverse outcomes. Changes in the sagittal plane position of the pelvis, owing both to patient positioning in the operating room and to altered spinopelvic alignment following surgery, potentially contribute to variation in component position. The dynamics of sagittal plane pelvic position before, during, and after THA have not been defined. We measured the differences in pelvic ratio, a measure of sagittal plane pelvic position, between preoperative, intraoperative, and postoperative anteroposterior (AP) radiographs of patients undergoing THA in the lateral decubitus position.

Introduction

Complete or nearly complete disruption of the gluteus attachment is seen in 10–20% of cases at the time of total hip arthroplasty (THA). Special attention is needed to identify the lesion at the time of surgery because the avulsion often is visible only after a thickened hypertrophic trochanteric bursa is removed. The purpose of this study was to evaluate a technique designed to restore abductor function by transferring the gluteus maximus to compensate for the deficient medius and minimus muscles.

Introduction

Within the field of arthroplasty, the use of patient-reported outcome measures (PROMs) is becoming increasingly ubiquitous in an effort to employ more patient-centered methods of evaluating success. PROMs may be used to assess general health, joint-specific pain or function, or mental health. General and joint-specific questionnaires are most often used in arthroplasty research, but the relationship between arthroplasty and mental health is less well understood. Furthermore, longitudinal reports of PROM changes after arthroplasty are lacking in the literature.

Our primary aim was to quantify the improvement in general, joint-specific, and mental health PROMs following total hip arthroplasty (THA) as well as the extent of any deterioration through the 7 years follow-up. Our secondary aim was to identify predictors of clinically significant PROM decline.

Introduction

The vast majority of intertrochanteric fractures treated with cephalomedullary nails (CMN) will heal. Occasionally even though bony union occurs excessive lag screw sliding can cause persistent pain and soft tissue irritation and return to surgery for hardware removal. The purpose of this study was to evaluate if fracture stability, lag screw tip-apex distance (TAD), and quality of reduction have any impact excessive lag screw sliding and potential cutout.

Introduction

Total hip arthroplasty (THA) is gaining popularity as a treatment for displaced femoral neck fractures (FNF), especially in physiologically younger patients. While elective THA for primary osteoarthritis (OA) has demonstrated low rates of complications and readmissions, the outcomes of THA for FNF are less predictable. Additionally, these THA procedures are equally included in various alternative payment bundles. Therefore, the aim of this study is to assess postoperative complication rates after THA for primary OA compared with FNF.

Introduction

The purpose of this study is to estimate the cost-effectiveness of performing total hip arthroplasty (THA) versus nonoperative management (NM) in non-obese (BMI 18.5–24.9), overweight (25–29.9), obese (30–34.9), severely-obese (35–39.9), morbidly-obese (40–49.9), and super-obese (50+) patients.

Introduction

Patients with rheumatoid arthritis (RA) have a higher risk of surgical site infection (PJI) than patients with osteoarthritis (OA). Disease modifying therapy is in widespread use in RA patients, and biologic medications may increase Staphylococcus aureus colonization rates. Because S. aureus colonization likely increases risk of surgical infection, perioperative assessments and therapies to decrease the risk of invasive S.aureus infections may be warranted. The objective of this study was to determine if there was a difference in S. aureus carriage among patients with RA, OA, and RA on biologics (RA+B).

Introduction

The role for hip arthroscopy (HS) in combination with periacetabular osteotomy (PAO) for the treatment of symptomatic acetabular dysplasia has not been clearly defined. In this study, we assessed midterm outcomes of concurrent hip arthroscopy and PAO (HS/PAO) for the treatment of symptomatic acetabular dysplasia with associated intra-articular pathology.

Introduction

Numerous musculoskeletal and systemic conditions may affect the hips of paediatric patients. While the large majority of patients go on to achieve positive outcomes, a small number will progress to end stage arthropathy with significant functional impairment. Management options have been significantly limited for this population. An adolescent hip arthroplasty program was developed with the aim to improve symptoms and quality of life for patients with pain and disability refractory to joint preserving management strategies.

Introduction

Early functional recovery following total hip arthroplasty (THA) has the potential to increase patient satisfaction and reduce resource utilization. The direct anterior approach (DA) has been shown to provide earlier recovery compared to the direct lateral (DL) approach based on functional tests and outcome scores. There are limited studies that objectively evaluate functional recovery comparing the two approaches in the early post-operative period. Activity trackers have emerged as a valid tool to objectively quantify physical activity levels and potentially better assess functional status compared to commonly reported functional questionnaires. The purpose of this study is to measure physical activity levels in patients undergoing THA with the DA approach and compare these to THA with the direct lateral approach in the immediate postoperative period.

Introduction

The influence of surgical approach for total hip arthroplasty (THA) on scar healing and scar perception is unknown. The purpose of this study was to evaluate patients’ perception of their scar following direct anterior (DA) or posterior approach (PA) for THA utilizing validated scar assessment scales.

Introduction

Because of concerns regarding excessive wear and short-term failures attributed to the metal-on-metal bearings, the use of metal-on-metal hip resurfacing arthroplasty (MOMHRA) has been greatly reduced since 2008, despite great mid-term results for well-designed implants and in certain patient populations. The true cause of excessive wear was then unknown. Therefore, identification of true risk factors for the procedure became paramount to refine indications and improve survivorship outcomes.

Introduction

Patient demand for hip and knee arthroplasty continues to rise. Information sources providing data on the volume and cost of Medicare total joint arthroplasty by hospital are of use to patients and healthcare professionals. Data have demonstrated that higher volume surgeons are associated with lower cost, morbidity, and mortality. The current study assesses if the same is true for hospitals.

Background

Prior research has shown that depression negatively impacts outcomes after total hip arthroplasty (THA); however, arthroplasty patients may also have depressive symptoms without an established diagnosis. The purpose of this study was to determine whether the Patient Health Questionnaire-2 (PHQ-2), a two-question depression screener, correlates with joint-specific symptom improvement after primary THA.

Background

Orthopedic surgeons have relied heavily on opiates after total hip replacement (THR) despite no clear evidence of benefit and a rapidly growing abuse epidemic. Multimodal analgesia may reduce or even obviate the need for opiates after elective surgery.

Introduction

Custom flanged acetabular components (CFAC) have been shown to be effective in treating complex acetabular reconstructions in revision total hip arthroplasty (THA). However, the specific patient factors and CFAC design characteristics that affect the overall survivorship remain unclear. Once the surgeon opts to follow this treatment pathway, numerous decisions need to be made during the pre-operative design phase and during implantation, which may influence the ultimate success of CFAC. The goal of this study was to retrospectively review the entire cohort of CFAC cases performed at a large volume institution and to identify any patient, surgeon, or design factors that may be related to the long-term survival of these prostheses.

Introduction

The goal of the current study was to determine if SES affects PROMs in patients treated with THA. Specifically, we sought to determine any potential differences between low and high SES patients in pre-surgical PROMs, post-surgical PROMs, and PROM improvement after surgery while controlling for any potential confounding demographic factors.

Aims

The routine use of dual-mobility (DM) acetabular components in total hip arthroplasty (THA) may not be cost-effective, but an increasing number of patients undergoing THA have a coexisting spinal disorder, which increases the risk of postoperative instability, and these patients may benefit from DM articulations. This study seeks to examine the cost-effectiveness of DM components as an alternative to standard articulations in these patients.

Introduction

As new innovations are developed to improve the longevity of joint replacement components, preclinical testing is necessary in the early stages of research into areas such as osseointegration, metal-cartilage wear and periprosthetic joint infection (PJI). Large-animal studies that test load-bearing components are expensive, however, requiring that animals be housed in special facilities that are not available at all institutions. Comparably, small animal models, such as the rat, offer several advantages including lower cost. Load-bearing implants remain difficult to manufacture via traditional methods in the sizes required for small-animal testing. Recent advances in additive manufacturing (3D metal-printing) have allowed for the creation of miniature joint replacement components in a variety of medical-grade metal alloys. The objective of this work is to create and optimize an image-based 3D-printed rat hip implant system that will allow in vivo testing of functional implant properties in a rat model.

Introduction

Despite well-fixed implants, persistent pain following total hip arthroplasty (THA) remains a concern. Various surgical approaches have been advocated, yet whether patient-reported pain differs amongst techniques has not been investigated. This study's purposes were to determine differences in patient-reported pain based on surgical approach (direct anterior –DA versus posterolateral-PL) or PL approach incision length. Our hypothesis was that no differences in patient-reported pain would be present.

Introduction

Several surgical approaches are available for elective total hip arthroplasty (THA) for osteoarthritis. While posterior surgical approaches are the most common, interest in a direct anterior (Hueter) approach is increasing because of alleged advantages in convalescence. However, no studies have examined differences in patient-reported global and condition-specific measures of health across multiple institutions. The ongoing Pulmonary Embolism Prevention after Hip and Knee Replacement (PEPPER) study is a PCORI-funded multicenter pragmatic clinical trial randomizing patients to three different antithrombotic regimens. We analyzed operative data from PEPPER to compare pre-post changes in validated patient-reported outcome measures after THA based on surgical approach.

Background

Hip dysplasia has traditionally been classified based on the lateral center edge angle (LCEA). A recent meta-analysis demonstrated no definite consensus and a significant heterogeneity in LCEA values used in various studies to define hip dysplasia and borderline dysplasia. To overcome the shortcomings of classifying hip dysplasia based on just LCEA, a comprehensive classification for adult acetabular dysplasia (CCAD) was proposed to classify symptomatic hips into three discrete prototypical patterns of hip instability; lateral/global, anterior, or posterior. The purpose of this study was to assess the reliability of this recently published CCAD.

Introduction

The aim of this study was to compare patient reported outcomes, radiographic measurements, and survival free from total hip arthroplasty (THA) in patients who underwent periacetabular osteotomy (PAO) for mild, moderate, or severe developmental dysplasia of the hip (DDH).

Introduction

As orthopaedics shifts towards value-based models of care, methods of evaluating the value of procedures such as a total hip arthroplasty (THA) will become crucial. Patient reported outcome measures (PROMs) can offer a meaningful way for patient-centered input to factor into the determination of value.

Despite their benefits, PROMs can be difficult to interpret as statistically significant, but not clinically relevant, differences between groups can be found. One method of correcting this issue is by using a minimal clinically important improvement (MCII), defined as the smallest improvement in a PROM determined to be important to patients.

This study aims to find demographic and surgical factors that are independently predictive of failing to achieve a MCII in pain and physical function at 1-year following THA.

Introduction

There are several potential biological mechanisms that may influence aseptic implant failure including excessive innate and adaptive immune responses to implant debris. We investigated the hypothesis that patients with painful total joint replacements will exhibit elevated levels of metal reactivity and inflammatory markers compared to patients with well-performing TJA. We evaluated this hypothesis by testing for metal hypersensitivity using in vitro LTT assay and analyzing serum levels of selected inflammatory markers.

Background

Delay in access to primary total hip (THA) arthroplasty continues to pose a substantial burden to patients and society in publicly funded healthcare systems. The majority of strategies to decrease wait times have focused on the time from surgical consult to surgery, however a large proportion of total wait time for these patients is the time from primary care referral to surgical consultation. Prioritization scoring tools and patient reported outcome measures are being used in an attempt to ration limited resources in the face of increasing demand. However, to our knowledge, no study has investigated whether a referral Oxford Hip Score (OHS) could be used to triage non-surgical referrals appropriately, in an effort to increase timely access to specialists for patients that are candidates for total joint replacement (TJR).

Introduction

Hip fractures are a common pathology treated by Orthopaedic surgeons. The Comprehensive Care for Joint Replacement (CJR) model utilizes risk stratification to set target prices for these patients undergoing hemiarthroplasty or total hip arthroplasty (THA). We hypothesized that sub-specialty arthroplasty surgeons would be able to treat patients at a lower cost compared to surgeons of other specialties during cases performed while on call.

Introduction

Single-stage resection and reimplantation for periprosthetic joint infection (PJI) in total hip arthroplasty (THA) is of recent interest, yet outcomes may be skewed by selected populations with healthier patients and less virulent organisms. This study quantified the effectiveness of a contemporary, evidence-based and standardized two-stage treatment protocol in patients with THA PJI including chronically infected, poor hosts.

Introduction

Two-stage revision surgery remains the gold standard as treatment for periprosthetic hip infections. The purpose of this study was to determine the rate of infection eradication after two-stage revision hip arthroplasty in patients treated with intraoperatively surgeon-molded articulating spacers as well as to foreshadow the future economical impact of these articulating antibiotic spacers to those commercially available.

Nobel Prize winning economist Paul Krugman described Moral Hazard as “…any situation in which one person makes the decision about how much risk to take, while someone else bears the cost if things go badly”.

The fidelity of some surgeons to their patients has been brought into question by recent press reports exposing a practice whereby one attending surgeon will be responsible for two patients undergoing surgery simultaneously. This is variously referred to as Overlapping Surgery, Concurrent Surgery, Simultaneous Surgery, Double-Booked Surgery or Ghost Surgery.

This practice entails surgeons in training (residents and fellows) performing varying degrees of the patient's surgery while the attending surgeon is operating elsewhere. In general, the patient is not informed of this substitution. When informed, most would not allow it.

Defenders of this practice site surgeon and hospital “efficiency”, independent operating experience by trainees, mass casualty triage and access to “in-demand” specialists.

Critics feel it “is a breach of ethical behavior”, that “The most likely motive for this is profit for both the surgeon and hospital” and “Overlapping surgery… threatens our obligation as orthopaedic surgeons to respect the primacy of patient welfare…”.

The American College of Surgeons, in response to public disclosures, created a policy on Overlapping Surgery. Its executive director wrote, “It is essential that the patient be informed of this practice and given enough notice so they may decide whether to seek care from another surgeon or at another institution*.

The US Senate Finance Committee investigated Overlapping/Concurrent Surgery practices. It expressed concerns over − 1) lack of informed consent, 2) plausible risks to patient safety, 3) use of Medicare billing regulations to determine acceptable surgical practices and 4) surgeons self- defining the “critical part” of the operation.

Studies to date do not resolve the propriety of this practice. All but one is short term. Most show longer surgical durations. Most show no increase in 30-day complication rates. The only long- term study found a 90% increase in complication rate in hip procedures at one year when surgery overlapped. None document the location of the surgeon during the procedure or report efficacy.

Over 7 million living Americans are beneficiaries of either a total hip or total knee replacement. These patients are made whole, their suffering relieved, their function and lives restored.

These miracles of modern medicine are not without cost. The United States spends $3.5 trillion dollars annually on health care, almost 20% of our GDP. Delivering health care is a grave responsibility and any person involved in it must understand the importance and consequences of their actions. The third leading cause of American deaths is medical errors. A recent study estimated that 4 out of 100 patients entering the hospital for surgery will die within seven days. Recognizing this, a surgeon's role as a patient's moral fiduciary, concerned primarily with protecting the interests of the patient, must be honored as a sacred trust.

The financial pressure on the surgeon from stagnant surgical fees is the elephant in the room that must be addressed in relation to this matter. When fees are cut, surgeons operate more.

Plato, in The Republic, recounts an allegory about a magic ring that makes its wearer invisible. He asks the question; Will the power of anonymity eliminate morality and ethics? When we as surgeons become “invisible” to our anesthetized patients during surgery, how will we answer that question?

Introduction

Interferon (IFN) based treatments for chronic hepatitis C (HCV) have been the standard of care until 2014 when direct antiviral agents (DAA) were introduced. Patients with HCV have had extremely high complication rates after total hip arthroplasty (THA). It is unknown whether HCV is a modifiable risk factor for these complications prior to THA. The purpose of this study was 1) to compare perioperative complication rates between untreated and treated HCV in THA and 2) to compare these rates between patients treated with two different therapies (IFN vs. DAA).

Aims

The aim of this study was to describe temporal trends and survivorship of total hip arthroplasty (THA) in very young patients, aged ≤ 20 years.

Aims

The aim of this study was to determine the stability of a new short femoral stem compared with a conventional femoral stem in patients undergoing cementless total hip arthroplasty (THA), in a prospective randomized controlled trial using radiostereometric analysis (RSA).

Aims

Recurrent infection following two-stage revision total hip arthroplasty (THA) for prosthetic joint infection (PJI) is a devastating complication. The purpose of this study was to report the survival of repeat two-stage revision hip arthroplasty, describe complications, and identify risk factors for failure.

The purpose of this randomized controlled trial is to evaluate the efficacy of using dilute betadine versus sterile saline lavage in aseptic revision total knee (TKA) and hip (THA) arthroplasty to prevent acute postoperative deep periprosthetic joint infection (PJI).

Of the 450 patients that were randomized, 5 did not have 90-day follow-up, 9 did not receive the correct treatment, and 4 were excluded for intraoperative findings consistent with PJI. 221 Patients (144 knees and 77 hips) received saline lavage only and 211 (136 knees and 75 hips) received a three-minute dilute betadine lavage (0.35%) prior to wound closure. Patients were observed for the incidence of acute postoperative deep PJI within 90 days of surgery. Statistical analysis was performed using t-tests or Fisher's exact test where appropriate. Power analysis determined that 285 patients per group are needed to detect a reduction in the rate of PJI from 5% to 1% (alpha=0.05, beta=0.20).

There were seven PJIs in the saline group and one in the betadine lavage group (3.2% vs. 0.5%, p=0.068). There were no significant differences in any baseline demographics between groups suggesting appropriate randomization.

Although we believe the observed difference between treatments is clinically relevant, it was not statistically significant with the sample size enrolled thus far and enrollment is ongoing. Nonetheless, we believe that these data suggests that dilute betadine lavage is a simple method to reduce the rate of acute postoperative PJI in patients undergoing aseptic revision procedures.

Total hip arthroplasty (THA) continues moving to the outpatient arena, and may be feasible for some conversion and revision scenarios. Controversy surrounds appropriate patient selection. The purpose of this study is to report complications associated with outpatient revision and conversion THA, and to determine if comorbidities are associated with complications or overnight stay.

From June 2013 through March 2018, 43 patients (44 hips) underwent conversion (n=12) or revision (n=32) THA at a free-standing ambulatory surgery center. Mean patient age was 58.4 years, and 52% of patients were male. Conversion procedures were for failed resurfacing in two, failed hemiarthroplasty in one, and failed fracture fixation with retained hardware in 9. Revision procedures involved head only in one, head and liner in 20, cup and head in 7, stem only in 2, and stem and liner in 2.

Forty-four (93%) were discharged same day without incident, none required transfer to acute facility, and 3 required overnight stay with 2 of these for convenience and only one for a medical reason, urinary retention. Three patients with early superficial infection were successfully treated with oral antibiotics. There were no major complications, readmissions, or subsequent surgeries within 90 days. One or more major comorbidities were present in 17 patients (39%) including 1 valvular disease, 8 arrhythmia, 2 thromboembolism history, 3 obstructive sleep apnea, 6 chronic obstructive pulmonary disease, 2 asthma, 4 frequent urination, and 1 renal disease. The single patient who stayed overnight for a medical reason had no major medical comorbidities.

Outpatient arthroplasty, including revision THA in some scenarios, is safe for many patients. Presence of medical comorbidities was not associated with risk of complications. The paradigm change of patient education, medical optimization, and a multimodal program to mitigate risk of blood loss and reduce need for narcotics facilitates performing arthroplasty safely in an outpatient setting.

Highly porous tantalum cups have been used in complex acetabular revisions for nearly 20 years but reports of long term results are limited. This study was designed to report ten year results of revision using a single porous tantalum cup design with special attention to re-operation for any reason, all-cause revision, and revision for aseptic loosening.

Retrospective review of all revision THA cases performed from 1999–2006 using a highly porous tantalum acetabular component design with multiple screw holes and a cemented polyethylene liner (Zimmer Biomet, Warsaw, IN). Our institutional medical record and total joint registry were used to assess follow-up and xrays were reviewed. The Paprosky classification system was used to rate acetabular bone loss. Radiographic loosening was defined as new/progressive radiolucencies in all 3 acetabular zones, or cup migration (>2mm). Kaplan-Meier survivorship was used to assess survivorship free of cup revision/removal for any reason, and free of revision for aseptic loosening.

Between 1999 and 2006 this tantalum cup was used in 916 revisions. Mean age: 66 (±6), BMI: 29 (±6), and male: 42%. Indications for revision: aseptic loosening 346 (38%), osteolysis 240 (26%), and infected arthroplasty 168 (18%). Large (3A or 3B) bone defects were present in 260, and pelvic discontinuity in 61. Reoperation for any reason: 133 (15%), but 84 of 133 cases did not require cup revision for instability (38) or femoral failure (24). Tantalum cup removal/revision was required in 49 (5.3%) for deep infection (39) and recurrent dislocation (6), and aseptic loosening (4). 10 year survivorship free of cup revision for any reason: 95% and for aseptic loosening: 99%. Radiographic review (mean 10 years): suspicious for aseptic loosening in another 4 cups.

A highly porous tantalum acetabular component with multiple screws and a cemented polyethylene insert provided durable long term fixation for an array of acetabular revision problems. Long term aseptic loosening was very rare (<1%) and cup removal was mainly related to deep infection, and rarely dislocation.

A total hip replacement (THR) patient's spinopelvic mobility might predispose them to an increased risk of impingement, instability and edge-loading. This risk can be minimised by considering their preoperative movement during planning of component alignment. However, the question of whether the preoperative, arthritic motion is representative of the postoperative mobility has been raised. We aimed to determine the change in functional pelvic tilt in a series of THR patients at one-year.

Four-hundred and eleven patients had their pelvic tilt and lumbar lordotic angle (LLA) measured in the standing and flexed-seated (position when patients initiate rising from a seat) positions as part of routine planning for THR. All measurements were performed on lateral radiographs. At 12-months postoperatively, the same two lateral images were taken and pelvic tilt measured. Pearson correlation was used to investigate the linear relationship between pre-and post-op pelvic tilt. Furthermore, a predictive model of post-op pelvic tilt was developed using machine learning algorithms. The model incorporating four preoperative inputs – standing pelvic tilt, seated pelvic tilt, standing LLA and seated LLA.

In the standing position, there was a mean 2° posterior rotation after THR, with a maximum posterior change of 13°. The Pearson correlation coefficient between pre-and post-op standing pelvic tilt was 0.84. This prediction of post-op standing tilt improved to 0.91 when the three further inputs were incorporated to the predictive model.

In the flexed-seated position, there was a mean 7° anterior rotation after THR, with a maximum anterior change of 45°. The Pearson correlation coefficient between pre-and post-op seated pelvic tilt was 0.54. This prediction of post-op seated tilt improved to 0.71 when the three further inputs were incorporated to the predictive model.

The best predictor of post-operative spinopelvic mobility, is the patients pre-operative spinopelvic mobility, and this should routinely be measured when planning THR

The predictive model will continue to improve in accuracy as more data and more variables (contralateral hip pathology, pelvic incidence, age and gender) are incorporated into the model.

Osteonecrosis of the femoral head (ONFH) is an ischemic disorder that causes bone and bone marrow necrosis. In spite of many studies, the primary cause of ischemia is still unknown. The purpose of this study is to identify the susceptibility genes in ONFH.

We performed a genome-wide association study (GWAS) in 1,602 ONFH cases and 60,000 controls. Stratified GWASs based on the 3 subgroups of ONFH (corticosteroids, alcohol, idiopathic) were also performed. We then evaluated the candidate gene in silico using public databases.

Two loci in 12q24.11–12 and 20q12 showed significant association with ONFH. A stratified analysis suggested that the 12q24 locus was associated with ONFH through the drinking capacity. In the 20q12 locus, LINC01370 was the only gene, which functions were related to the plausible biological pathway for the development of ONFH.

A novel ONFH locus was identified at chromosome 20q12, and LINC01370 was the best candidate gene in this locus.

In recent years, the direct anterior approach (DAA) has become a standard approach for primary total hip arthroplasty (THA). With the increasing use of the DAA in primary cases also more and more revision surgeries are performed through the same interval. With ability to extend the DAA interval proximally and distally, loose cups, loose stems, and even periprosthetic femoral fractures (PPF) can be treated. Especially, PPF are devastating complications causing functional limitations and increased mortality. Therefore, we conducted a study to report the outcome of surgical treatment of PPF with the DAA interval.

We report on the one year complications and mortality in 40 cases with a mean clinical follow-up of 1.5 years. Mean age of patients was 74.3 years. Fractures were classified as Vancouver B2 (36), and B3 (N=4). In 14 cases, a standard stem was used, and in 26 cases a modular revision stem. In 30 cases, a distal extension +/- tensor release was used, in 4 cases a proximal tensor release was done, and in the remaining 6 cases revision could be performed without extension of the approach.

Median cut/suture time was 152 minutes (IQR 80 – 279). The overall complication rate in our patient group was 12.5%. 2 patients died in the first three months after operation. One patient had a transient femoral nerve palsy, which completely recovered.

The DAA interval to the hip for the treatment of PFF showed similar results compared with other approaches regarding mortality, complications, fracture healing, dislocation rate and clinical results. We conclude that femoral revision in case of PPF in the DAA interval is a safe and reliable procedure. Each Vancouver type of periprosthetic fracture can be treated by use of this approach.

Arthroplasty registries have played a key role in the treatment of patients with various joint diseases and conditions since their conception. Swedish hip and knee arthroplasty registries were initiated in late 1970's. The main aim of registries was to create feedback to surgeons. During the last two decades with introduction of patient reported outcomes, data from registries have been increasingly used to compare caregivers and to improve quality of health care. According to the Swedish Hip Arthroplasty Register (SHAR) Sahlgrenska University Hospital had been underperforming during years 2006–2012. In order to improve the outcomes a systematic data driven approach using local and national registries, based on value based management was undertaken.

Representatives from all categories of healthcare staff and patients were invited to join a newly initiated group. The group was asked to define which measurement that contributed most to improve healthcare. Data from SHAR and local registries were used and seventeen different areas of improvement were identified. Several workgroups were initiated.

Between years 2013 and 2017 there was an increase of 60% in the annual volume of elective THAs. The length of stay decreased from 6.4 days to 1.8 days. Satisfaction with outcome of surgery increased from 76% to 90%. Adverse events decreased from 28% to 10%. The risk of re-operations within 2 years decreased from 2.4% to 1.9%.

Data from a national and a local registry were used to identify and implement changes in a large university hospital. Engaging member of staff and creating a graphical tool for continuous feedback drastically improved the quality of care whilst increasing the availability of hip replacements and reducing costs. This project demonstrates the power of registry data and a patient centered approach in engaging staff and improving healthcare.

The modified Dunn procedure has the potential to restore the anatomy in hips with slipped capital femoral epiphyses (SCFE) while protecting the blood supply to the femoral head. However, there is controversy about the risks associated with the procedure especially in the most severe capital slips.

Therefore, we report on (1) clinical outcome, (2) the cumulative survivorship with endpoints AVN and/or OA progression and (3) radiographic anatomy of the proximal femur at followup in patients treated with a modified Dunn procedure for severe SCFE.

We performed a retrospective analysis involving 46 hips of 46 patients treated with a modified Dunn procedure for severe SCFE (slip angle >60°) between 1999 and 2016.

Followup averaged 8 years, (range 1–17) with 2 patients lost to followup after one year.

The mean age was 13 years (range 9–19 years). Mean preoperative slip angle was 64° (range 60–90) and 14 out of 46 hips (30%) presented with unstable slips.

Clinical scores and PROMs were evaluated and the hips were followed standard x-rays. Cumulative survivorship (Kaplan-Meier) with three defined endpoints: (1) AVN; (2) progression by at least one OA grade according to Tönnis; (3) non-preserved hip joint.

(1)Mean Harris Hip score (HHS) was 93 points (66–100) and mean Hip Disability and Osteoarthritis Outcome Score (HOOS) was 90 points (67–100) at last followup.

(2)Cumulative survivorship was 93% at 10-year followup. Three hips reached an endpoint. Two hips (4%) had AVN, one of them underwent hip arthrodesis. One hip had OA progression.

(3)Postoperative slip angle was 7° (1–16). Alpha angle on axial radiograph was 39° (26–71) at followup. 41/44 hips (93%) had no OA (Tönnis 0).

The modified Dunn procedure largely corrected slip deformities with low apparent risk of progression to avascular necrosis or osteoarthritis at mean 8-years followup. The AVN rate in severe and unstable (30%) capital slip was 4% (2 hips) with this procedure.

Adolescent and young adult patients with a history of DDH and residual hip dysplasia tend to have an early presentation of symptoms. In these patients, a severe acetabular dysplasia, aspheric femoral head and/or high greater trochanter are often observed. We evaluated the long-term results of rotational acetabular osteotomy (RAO) for symptomatic hip dysplasia in patients younger than 21 years.

We performed 492 RAOs for hip dysplasia from 1987 to 2017. In these cases, patients younger than 21 years at the time of surgery were 40 patients (46 hips). We evaluated 34 patients (40 hips, follow-up rate; 85%) retrospectively. There were 32 females and two males; their mean age at the time of surgery was 17.8 years (12–21). The mean follow-up period was 16.8 years (1–30). In eight hips, isolated RAO was not adequate to correct instability and/or congruency. For these hips, four varus femoral osteotomies, two valgus femoral osteotomies and two greater trochanter displacement were combined with RAO.

The mean clinical score (JOA) was improved from 80 to 90 significantly at the final follow-up. The mean CE angle was improved from −3.4 (−35–10) degrees to 27 (8–42) degrees, acetabular roof angle from 30 (15–60) degrees to 6.7 (−3–30) degrees, head lateralization index from 0.665 (0.5–1.0) to 0.614 (0.429–0.7) postoperatively. Radiographic OA progression was observed in four hips, but no hip was converted to THA.

The RAO is an effective technique for surgical correction of a relatively severe dysplastic hip in adolescent and young adults.

A randomized trial was designed to compare the outcome of ceramic-on-ceramic with ceramic on conventional polyethylene. These patients have been followed for 15 years.

58 hips in 57 patients under 60 years of age were randomized into one of two groups. Patients were blinded to the type of hip they received. Both groups of patients were treated routinely with prophylactic peri-operative antibiotics and low molecular weight Heparin. All patients were seen at six weeks, three months and annually after surgery. Clinical and radiologic assessment was carried out at each visit.

Fifty-eight hips were available for analysis, 28 in the CoP group and 29 patients in the CoC group. Mean age of both groups was less than 45 years.

There were seven revisions (16%) among the 58 patients enrolled in the study. In the CoP group four patients underwent revision with head and liner exchange for eccentric polyethylene wear 16 years post-implantation. In the CoC group one patient had a cup revision at 15 years for acute aseptic instability of the acetabulum; two additional patients in the CoC group had femoral head exchange, one for fracture and one for trunnion corrosion. Both occurred 14 years after the index surgery.

Functional outcome scores showed no difference between the two groups at 15 years. Radiographically there was a statistically difference in wear between the two groups.

This study demonstrates that both ceramic-on-ceramic and ceramic-on-polyethylene produce satisfactory functional results with low revision rates in young patients.

We report on an innovative surface grafting to highly crosslinked (HXLPE) bearing for THA using a biocompatible-phospholipid-polymer poly (2-methacryloyloxyethyl phosphorylcholine) (PMPC). Such hydrophilic surfaces mimic articular cartilage and are hypothesized to improve lubrication and thereby reduce friction and wear.

We performed in vitro testing of wear and friction of ceramic-on-polyethylene THRs with the PMPC treatment, and compared them with untreated controls. Highly cross-linked UHMWPE bearings, gamma-ray-irradiated at different levels with and without vitamin E (HXL Vit. E: 125 kGy, HXL: 75 kGy, respectively) were divided so half were PMPC treated (n=3 for all four groups). All were paired with identical 40 mm diameter zirconia-toughened-alumina ceramic heads. Testing was carried-out on an AMTI hip simulator for 10 million simulated walking cycles with standard lubricant and conditions (ISO-14242-1). Wear was measured gravimetrically at 21 intervals, and so was frictional torque with a previously described and tested methodology.

PMPC treatment produced a statistically significant 71% in wear reduction of HXL poly (1.70±1.36 mg/Mc for PMPC vs. 5.86±0.402 mg/Mc for controls, p=0.013). A similar significant wear reduction was found for PMPC treated HXL with Vit. E liners (0.736±0.750 mg/Mc, vs. 2.14±0.269 mg/Mc, p=0.035). The improvements were associated with 12% and 5% reductions in friction of the HXL and Vit. E HXL respectively (statistically significant p=0.003, and marginal p=0.116, one tailed).

These results were an important step in the quest for lower wearing, thin and strong UHMWPE liners for larger diameter femoral heads with the potential benefit of longevity and less risk of dislocation after surgery.

The primary purpose of the current study was to evaluate and compare the wear properties of vitamin E-doped, highly-crosslinked PE (VEPE) and one formulation of moderately cross-linked and mechanically-annealed ultra-high molecular weight PE (ModXLPE) in patients five years after primary THA. We also sought to understand whether polyethylene wear is associated with radiographic evidence of bone resorption or with deterioration in patient-reported outcome measures (PROMs).

A total of 221 patients from four international centers were recruited into a prospective RSA and clinical outcomes study. Seventy percent (76%) of patients received VEPE (vs. ModXLPE) liners, and 36% received ceramic (vs. metal) femoral heads. PROMs and radiographs were collected preoperatively and at one, two, and five years postoperatively. In addition, RSA radiographs were collected to measure PE wear.

We observed similar bedding in through the one-year interval and wear through the two-year interval between the two liner types. However, there was significantly more femoral head penetration in the ModXLPE cohort compared to the VEPE cohort at the five-year follow-up (p<0.001). The only variables independently predictive of increased wear were ModXLPE (vs VEPE) liner type (β=0.22, p=0.010) and metal (vs. ceramic) femoral head type (β=0.21, p=0.013). There was no association between increased wear and radiolucency development (p=0.866) or PROMs. No patients were found to have evidence of osteolysis.

At five-years postoperatively, patients treated with VEPE (vs. ModXLPE) and ceramic (vs. metal) femoral heads demonstrated decreased wear. At the longest follow-up (five years postoperatively), the wear rates for both liner groups were very low and have not led to any osteolysis or implant failures via aseptic loosening.

Obesity has previously been demonstrated to be an independent risk factor for increased complications following total hip (THA) and total knee arthroplasty (TKA). The purpose of this study was to compare the effects of obesity and BMI to determine whether the magnitude of the effect was similar for both procedures.

We queried the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database to identify patients who underwent primary THA or TKA between 2010 and 2014. Patients were stratified by procedure and classified as non-obese, obese, or morbidly obese according to BMI. Thirty-day rates of wound complications, deep infection, total complications, and reoperation were compared using univariate and multivariate logistic regression analyses.

We identified 64,648 patients who underwent THA and 97,137 patients who underwent TKA. Obese THA patients had significantly higher rates of wound complications (1.53% vs 0.96%), deep infection (0.31% vs 0.17%), reoperation rate (2.11% vs 1.02%), and total complications (5.22% vs. 4.63%) compared to TKA patients. Morbidly obese patients undergoing THA were also found to have significantly higher rates of wound complications (3.25% vs 1.52%), deep infection (0.84% vs 0.23%), reoperation rate (3.65% vs 1.60%), and total complications (7.36% vs. 5.57%). Multivariate regression analysis identified increasingly higher odds of each outcome measure as BMI increased.

This study demonstrates the impact of obesity on postoperative complications is more profound for THA than TKA. This emphasizes the importance of considering patient comorbidities in the context of the specific procedure (hips and knees should be analyzed independently) when assessing risks of surgery.

Trunnionosis is an important failure mechanism of total hip arthroplasties as has recently been reported by the England and Wales national joint registry. Adverse local tissue reaction has also recently been associated with total hip arthroplasty (THA) with metal on polyethylene and ceramic on polyethylene articulations. The contributing factors in the mechanism of this failure pattern have not been elucidated, however they are likely multifactorial to include corrosion, fretting, taper design, implantation time, metal particulate debris, and wear at the metal on metal interface. Furthermore, dissimilar metallic combinations have been shown to exacerbate tribocorrosion. Authors have also reported on the use of ceramic heads to reduce trunniononis, however, tribocorrosion is still present. The majority of the literature regarding modular head neck taper fretting and corrosion involves cobalt chrome (CoCr) alloy. Little is known about head neck fretting corrosion with Oxinium femoral heads.

To measure fretting, corrosion, and wear on the female tapers of retrieved Oxinium femoral heads and to determine how demographic and device factors affect these measurements.

Ninety-two (92) retrieved 12/14 Oxinium heads were graded using the modified Goldberg score for subjectively grading corrosion and fretting on the taper surface. A novel silicone molding technique was validated, then applied to the female tapers of the retrievals and of two pristine Oxinium femoral heads, sizes 32+0 and 32+4. The molds were scanned using a Konica Minolta 3D laser scanner for reconstruction of the topography, dimensions, and surface features of the tapers. Geomagic software was used to align the retrieved to the pristine 3D models, allowing measurement of surface deviations (from wear) that had occurred while the heads were implanted. Patient demographic and implant data were correlated with Goldberg scores and wear deviations.

The mean Goldberg score was 1.6. Goldberg scores of 1 (minimal), 2 (mild), and 3 (moderate) were present in 41 of the 92 heads (45%), 43 heads (47%), and 8 heads (8%) respectively. No implants received a score of 4 (severe). A positive significant correlation was found between length of implantation and increased female taper fretting (R = 0.436, p < 0.01). Wear deviations were significantly greater with 36mm heads compared to 32mm heads (p < 0.01) and with +4 offsets compared to 0 offsets (p = 0.013).

Similar to previous work analyzing ceramic heads, Oxinium heads demonstrated predominately mild tribocorrosion grades, however do not eliminate tribocorrosion. Tribocorrosion was increased with large heads and increased offsets. This finding is consistent perhaps with greater mechanical burden that larger implants with increased offsets experience. Further investigation is needed to elucidate if Oxinium femoral heads reduce fretting and corrosion when compared to CoCr femoral heads.

Periacetabular osteotomy (PAO) is a demanding procedure that puts patients at risk for potentially significant blood loss, and blood transfusions. Avoidance of transfusions in otherwise healthy young patients is important. This project was designed to study the effectiveness of our blood conservation efforts.

178 consecutive PAOs performed in one hospital by one surgeon (RFS) from 2008 to 2016 were reviewed retrospectively. PAO's were performed in other hospitals, too, but a majority were from the study group hospital. Data were collected from digitalized patient office charts and hospital electronic medical records. Collected data were analyzed for categorical associations between blood loss, demographic data, and transfusion risks.

Over the past 27 months, the transfusion rate in 63 consecutive patients has been reduced to Zero. Discontinuation of drains, use of TXA, spinal anesthesia, reducing trigger for transfusion to Hgb of <7, cell saver use in all cases, and careful intraop coagulation, among others, have been incrementally incorporated. The overall transfusion rate was 10.7% for all patients. In the early years of this study, prior to adoption of all of these blood conservation measures, the transfusion rate was 12.5%. Over the past four years the transfusion rate was 1.5%. Over the last two years it has been zero.

There is little data specifically regarding transfusion rates in PAOs but this study establishes that an aggressive approach to blood saving techniques and limitation of bleeding can reduce the risk of transfusion to virtually zero in this population of mostly young patients.

We investigated the preliminary results of femoral head necrosis treated by modified femoral neck osteotomy through surgical hip dislocation in young adults.

33 patients with femoral head osteonecrosis received modified femoral neck osteotomy through surgical hip dislocation from March 2015. 14 patients who had minimal 12 months of follow-up were reviewed radiographically and clinically (mean follow-up:16 months, 12–36 months). The mean age of the patients 32 years at the time of surgery (ranged from 16 to 42years). There were 6 women and 8 men. The cause of the osteonecrosis was steroid administration in 6, alcohol abuse in 4, trauma in 3, and no apparent risk factor in 1. According to the Ficat staging system, 1 hips was stage II, 9 hips III, and 4 hips stage IV. The posterior or anterior rotational angle was 90–180° with a mean of 143°. Clinical evaluation was performed in terms of pain, walk and range of motion on the basis of Merle d'Aubigné hip scores: 17–18 points are excellent, 15–16 are good, 13–14 are fair, 12 or less are poor.

Recollapse of the final follow-up anteroposterior radiograph was prevented in 13 hips. One patient got 1 mm recollapse 18 months after surgery. No patient got progressive joint space narrowing. The Merle d'Aubigné score was excellent in 7 hips, good in 5, fair in 2.

The preliminary results suggest that modified femoral neck osteotomy through surgical hip dislocation is in favor of young patients. But longer term follow-up is necessary.

Hip and knee revisions continue to increase in number and complexity. With an understanding that revisions have a high re-revision rate, the importance of correct decisions made at the index procedure, is paramount for patients and surrounding health care economy.

Since January 2015, East Midlands Specialist Orthopaedic Network, (set up on a ‘hub-and-spoke’ model), has allowed all revisions performed within our region, (5 hospitals with a 4 million population), to be discussed at a weekly ‘web’ conference. Integrated radiology allows clinical information to be reviewed remotely at each hospital. Chaired by specialist revision surgeons, with other surgeons, a microbiologist and radiology, vascular, plastics opinions available as required, a formal management plan is ‘signed off’ by the chair and returned to referring institution. We present prospective data of Network activities.

To January 2018, 1007 cases have been referred by 18 consultants from 5 hospitals. A change in proposed plan was seen in 48% cases. (40% involved technique and exposure advice; 18% involved surgical inventory; 22% further investigation; 11% microbiological input; 9% other miscellaneous advice) Few (5%) patients were transferred directly. We also identified 20% increase in outpatient referrals to the ‘hub’.

The network is an excellent tool for discussing complex cases, supporting surgeons in smaller units. A significant number of alterations in plan are made with a few patients transferred directly. We feel the network can only enhance care and are working now to identify exactly how it has affected clinical outcomes. We encourage others to adopt this approach.

To investigate the clinical results of capsular arthroplasty in the treatment of young patients with unilateral hip dislocation.

We retrospectively evaluated all patients who had the capsular arthroplasty from June 2012 to September 2016 in our department. Hips were evaluated using hip Harris score (HHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. The Tonnis osteoarthritis grade and Severin classification were used to access the radiographic outcomes.

Fifty-nine patients (10 males and 49 females) with an average of 16.8y (range: 8–26y) were followed by a mean of 32.1 months (range: 12.5–66.0 months). The mean HHS was 83.4 (range: 31.2–99) and WOMAC score was 12.3 (range: 0–49) at the final follow up. Multivariate analysis revealed that the poor capsular quality (OR=8.29) was associated with the poor result. The thicker capsule (OR=0.83) and bigger femoral head (OR=0.73) were associated with the good result. There were 15 patients (25.4%) identified as Tonnis grade 0, 21 patients (35.6%) as grade 1, 18 patients (30.5%) as grade 2 and 5 patients (8.5%) as grade 3. According to Severin classification, 28 patients (47.6%) were regarded as class I, 22 patients (37.3%) as II, 7 patients (11.9%) as III and 2 patients (3.4%) as IV. One patient underwent THA after 41.5 months. The joint stiffness was the most common complication (10.2%).

We confirmed the efficacy of the capsular arthroplasty in the treatment of young patients with unilateral hip dislocation. The capsular quality and the size of femoral head were associated with the clinical results.

The principle function of the “short external rotator” muscle group is primarily as an abductor and extensor of the flexed hip and is better referred to as the “Quadriceps Coxa” (QC). The QC has a profound influenced on weight bearing rising and propulsive motions. The SPAIRE technique preserves Obturator Internus (OI) and Piriformis (P) resulting in improved stability of the hip and potentially improved recovery and function in patients undergoing hip arthroplasty.

Short term outcomes of the first 42 consecutive SPAIRE cases are compared with 86 consecutive cases using the traditional posterior approach that immediately preceded introduction of the technique. The purpose was to document the learning curve and confirm the safety of introducing SPAIRE into routine clinical practice.

The two groups were comparable and there was no statistically significant difference in length of stay, blood loss, intra-or post-operative complications nor radiological measurements relating to the femoral or acetabular components. Statistically significant differences were found for component usage (more uncemented acetabula for SPAIRE), length of operation (8 mins longer with SPAIRE); patient satisfaction was higher at 6 weeks and measured leg length discrepancy less in the SPAIRE group.

SPAIRE has been used routinely for all routine arthroplasties for over two years. RCTs are ongoing to document the effect of SPAIRE on recovery, long term function and activity level. If the potential benefits are confirmed SPAIRE may become the default technique for hip arthroplasty operations through a posterior approach for elective and hip fracture cases.

Stress shielding has been a well-recognised problem with uncemented femoral components resulting in proximal bone loss and dysfunction, but less attention has been paid to the preservation of acetabular bone stock. Uncemented acetabular components often demonstrate reduced bone density on plain radiographs in the mid-portion of the cup (zone 2), which may be due to the rigidity of the outer shell. This study compares the change in bone density around three different cups with varying moduli of elasticity at a minimum of 2 years. Our hypothesis was that less rigid cups would be associated with improved bone density and less stress shielding.

This prospective randomised controlled trial compared the bone mineral content (BMC) adjacent to three different cups with marked differences in stiffness. Cup A was an all titanium shell, cup B was a titanium coated all polyethylene implant and cup C was a tantalum backed shell. All articulations used a 32mm ceramic femoral head. Cup B used polyethylene modified by treatment with vitamin E whereas cups A and C used a liner made of irradiated cross linked polyethylene.

Five regions of interest (ROI) were established adjacent to the cup, regions 2, 3 and 4 where similar to the DeLee and Charnley regions 1, 2 and 3. Bone density was measured using IDXA preoperatively, postoperatively, 6 months, 1 and 2 years and compared for each ROI and implant.

Precision measurements showed significant reliability. All areas showed a reduction in BMC following insertion of the acetabular cup. Bone loss was less in ROI 1 and 4 in the area of rim fit for all cups and the maximal bone loss was seen in ROI 2 and 3 at the dome of the cup. The more elastic cup (Cup B) produced the least bone loss in this area (p<0.05). Cup C produced the largest bone loss at ROI 2 (40%) which continued increasing at 2 years.

Cup stiffness is related to bone loss adjacent to the acetabulum, presumably due to a similar process of stress shielding as seen in the femur. All cups produced similar changes at the periphery of the cup but the more elastic cup retained bone density beneath the cup which continued past 2 years. This improvement in bone quality is likely to be associated with better acetabular bone stock into the future and more reliable long term cup fixation.