Ideally the hip arthroplasty should not be subject to bony or prosthetic impingement, in order to minimise complications and optimise outcomes. Modern 3d planning permits pre-operative simulation of the movements of the planned hip arthroplasty to check for such impingement. For this to be meaningful, however, it is necessary to know the range of movement (ROM) that should be simulated. Arbitrary “normal” values for hip ROM are of limited value in such simulations: it is well known that hip ROM is individualised for each patient. We have therefore developed a method to determine this individualised ROM using CT scans.

CT scans were performed on 14 cadaveric hips, and the images were segmented to create 3d virtual models. Using Matlab software, each virtual hip was moved in all potential directions to the point of bony impingement, thus defining an individualised impingement-free 3d ROM envelope. This was then compared with the actual ROM as directly measured from each cadaver using a high-resolution motion capture system.

For each hip, the ROM envelope free of bony impingement could be described from the CT and represented as a 3d shape. As expected, the directly measured ROM from the cadaver study for each hip was smaller than the CT-based prediction, owing to the presence of constraining soft tissues. However, for movements associated with hip dislocation (such as flexion with internal rotation), the cadaver measurements matched the CT prediction, to within 10°.

It is possible to determine an individual's range of clinically important hip movements from a CT scan. This method could therefore be used to create truly personalised movement simulation as part of pre-operative 3d surgical planning.

The objectives of the study were to investigate demographic, injury and surgery/treatment-associated factors that could influence clinical outcome, following Autologous Chondrocyte Implantation (ACI) in a large, “real-world”, 20 year longitudinally collected clinical data set.

Multilevel modelling was conducted using R and 363 ACI procedures were suitable for model inclusion. All longitudinal post-operative Lysholm scores collected after ACI treatment and before a second procedure (such as knee arthroplasty but excluding minor procedures such as arthroscopy) were included. Any patients requiring a bone graft at the time of ACI were excluded. Potential predictors of ACI outcome explored were age at the time of ACI, gender, smoker status, pre-operative Lysholm score, time from surgery, defect location, number of defects, patch type, previous operations, undergoing parallel procedure(s) at the time of ACI, cell count prior to implantation and cell passage number.

The best fit model demonstrated that for every yearly increase in age at the time of surgery, Lysholm scores decreased by 0.2 at 1-year post-surgery. Additionally, for every point increase in pre-operative Lysholm score, post-operative Lysholm score at 1 year increased by 0.5. The number of cells implanted also impacted on Lysholm score at 1-year post-op with every point increase in log cell number resulting in a 5.3 lower score. In addition, those patients with a defect on the lateral femoral condyle (LFC), had on average Lysholm scores that were 6.3 points higher one year after surgery compared to medial femoral condyle (MFC) defects. Defect grade and location was shown to affect long term Lysholm scores, those with grade 3 and patella defects having on average higher scores compared to patients with grade 4 or trochlea defects.

Some of the predictors identified agree with previous reports, particularly that increased age, poorer pre-operative function and worse defect grades predicted poorer outcomes. Other findings were more novel, such as that a lower cell number implanted and that LFC defects were predicted to have higher Lysholm scores at 1 year and that patella lesions are associated with improved long-term outcomes cf. trochlea lesions.

Aims

After failed acetabular fractures, total hip arthroplasty (THA) is a challenging procedure and considered the gold standard treatment. The complexity of the procedure depends on the fracture pattern and the initial fracture management. This study’s primary aim was to evaluate patient-reported outcome measures (PROMs) for patients who underwent delayed uncemented acetabular THA after acetabular fractures. The secondary aims were to assess the radiological outcome and the incidence of the associated complications in those patients.

Abstract

Aims

The increase in prescription opioid misuse and dependence is now a public health crisis in the UK. It is recognized as a whole-person problem that involves both the medical and the psychosocial needs of patients. Analyzing aspects of pathophysiology, emotional health, and social wellbeing associated with persistent opioid use after injury may inform safe and effective alleviation of pain while minimizing risk of misuse or dependence. Our objectives were to investigate patient factors associated with opioid use two to four weeks and six to nine months after an upper limb fracture.

BACKGROUND

Optimal perioperative fluid management has not been established in patients undergoing orthopaedic surgical procedures. Our purpose was to investigate the effects of perioperative fluid management on patients experiencing TKA.

Background

Over 10% of total hip arthroplasty (THA) surgeries performed in England and Wales are revision procedures¹. Malorientation of the acetabular component in THA may contribute to premature failure due to mechanisms such as edge loading and prosthetic impingement. It is known that the pelvis flexes and extends during activities of daily living (ADLs), and excessive pelvic motion can contribute to functional acetabular malorientation. Preoperative radiographs can be performed to measure changes in pelvic tilt during ADLs to identify high risk individuals and inform surgical decision making. However, radiographs require time-consuming radiation exposure, and are unable to provide truly dynamic 3-dimensional analysis. The purpose of this study was to develop and evaluate a motion capture method using inertial measurement units (IMUs). This would provide a rapid, non-invasive analysis of pelvic tilt which could be used to support surgical planning.

Background

It is not always clear why some patients experience recurrent dislocation following total hip arthroplasty (THA). In order to plan appropriate revision surgery for such patients, however, it is important to understand the specific biomechanical basis for the dislocation. We have developed a novel method to analyse the biomechanical profile of the THA, specifically to identify edge loading and prosthetic impingement, taking into account spinopelvic mobility. In this study we compare the results of this analysis in THA patients with and without recurrent dislocation.

Introduction

Patient related outcome measures (PROMS) are now routinely undertaken in patients undergoing hip arthroplasty. These are in the form of the Oxford Hip Score (OHS) and EQ5D questionnaires pre-operation and at 6 months' post operation. MYMOPS is a patient specific outcome measure that allows patients to list their individualised symptoms and activities that are limited and is used is other medical specialities but not currently within orthopaedic surgery. The aim of this study was to validate the MYMOPS questionnaire for use in hip arthroplasty by comparing it to the OHS.

Background

This clinical study aims to establish the rate of operative inadvertent hypothermia (IH) in elderly hip fracture patients (>65 years old). We postulate that differences exist in risk factors and hypothesised poorer outcomes in patients with IH.

Derriford Hospital gained Major Trauma Centre (MTC) status in April 2012, this led to a significant increase in the trauma case load. Our aim was to review registrar exposure to theatre and clinic in the elective and trauma setting. This was then compared to audits performed pre-MTC status and shortly following MTC changes to see if training standards were being maintained. Improvements in registrar rota planning were made following the previous assessment of training. Training was assessed with respect to national recommendations for registrar training.

Data was collected for 8 weeks in February and March 2014 for all 12 registrars, and cross-referenced with the on-call and daily rota. The data was divided into training and non -training registrars

Elective exposure had improved in both theatres and clinic along with trauma theatre exposure whilst fracture clinic exposure had reduced since the previous audit. The reduction may be a result of the on-call registrar no longer being present in fracture clinic when on-call in compliance with MTC guidance.

Rota management requires a fine balance between service and training commitments. Recent improvements to the management of the registrar rota appear to provide satisfactory training despite the pressures of MTC changes at Derriford Hospital.

Infection in arthroplasty surgery is a major complication leading long antibiotic courses and frequently requiring repeated operations to eradicate or suppress. Therefore in the situation of revision surgery on prosthesis that are possibly already infected a clear identification of possible infection is required. Previously frozen section samples have been used in Derriford Hospital in conjunction with clinical presentation and other investigations to aid in diagnosis and tailor management, however recent studies have suggested that this may not be as effective as previously thought. Kanner et al. (2008) suggested a sensitivity of 29% and positive predictive value of 40%.

This retrospective audit reviewed the cases between March 2007 and May 2012, identifying 220 cases of revision surgery where infection was suspected and frozen sections analysis was performed. Results where then compared to paraffin and cultured samples if taken. A notes review was performed to demonstrate if the operative technique (single or two stage) was in line with local guidelines for the results of the frozen section. Long term survival (longest follow up of 7 years) was assessed by need for revision surgery.

There has been a trend towards operative management of pelvic injuries. Posterior pelvic integrity is more important for functional recovery. Percutaneous iliosacral screw fixation is being increasingly preferred for posterior pelvic stabilisation. Outcome reporting for this procedure remains inconsistent and un-standardised.

Retrospectively, all percutaneous iliosacral screw fixations done at this institute during a 5-year period (2008–2012) were reviewed. 28 patients, who had had at least 12 months follow-up, were contacted and clinical scoring was done by postal correspondence. Radiographs were measured for displacements and leg-length discrepancy. Possible factorial associations and correlations were investigated.

Mean Majeed score was 83 (median 87), mean EQ-Visual Analog Score (EQ-VAS) was 75.5 (median 80) and the two scores were correlated with statistical significance. Tile AO type C injuries produced worse outcomes and patients who'd anterior pelvic fixation did better.

Our results show high patient-reported outcomes, excellent radiologically measured reductions and unions. The incidence of complications is very low. There is a significant correlation between the EQ-VAS arm of the EQ5D instrument and the Majeed score in this patient population. Incidence of non-pelvic surgical procedures in these patients was significantly associated with worse outcomes. Leg length discrepancies appeared to increase after patients were fully weight bearing.

Plymouth Hospitals NHS Trust developed a pelvic and acetabular service in 2008, with the aim to provide a tertiary service for Devon and East Cornwall.

We describe the demographics of the patients, referral and fracture patterns, the operative management undertaken and complications seen in a newly developed tertiary pelvic and acetabular service in the South West.

Over 150 patients have been referred and treated, with follow up in a specialised tertiary clinic. Clinical scoring and radiological follow up were performed, and complications recorded.

Several difficulties and problems were encountered in the development of the service including training issues, equipment availability, surgeon availability, referral pathways and theatre time.

The presentation will describe the clinical results of the service, along with the logistical obstacles encountered in setting up a new service.

Purpose

The purpose of this study was to determine whether intra-operative identification of osseous ridge anatomy (lateral intercondylar “residents” ridge and lateral bifurcate ridge) could be used to reliably define and reconstruct individuals' native femoral ACL attachments in both single-bundle (SB) and double-bundle (DB) cases.

Background

Body Mass Index (BMI) is used to quantify generalised obesity, but does not account for variations in soft tissue distribution.

1737 elective foot and ankle cases were prospectively audited from Dec 2005 to end June 2010. All cases were brought back to a specialist nurse dressing clinic between 10 and 17 days post op. Data was collected at the dressing clinic with a standardised proforma on the type of surgery, the state of the wound and any additional management required. Those patients with a pre-existing infection were excluded.

Of the 1737 cases 201 (11.6%) had a minor wound problems such as excessive post op bleeding into the dressings, suture problems, early removal of K wires, delayed wound healing and minor infection. 42 patients required antibiotics (2.4%) 8 patients had a deep wound infection (0.5%) requiring intravenous antibiotics and or further surgery.

There were 1185 forefoot procedures 36 of which developed an infection (3%), overall infections of the mid/hindfoot was 6 (1%).

Practice has changed as a result of the audit (reviewed annually). We have changed our closure techniques (reducing suture problems). For the past 2 years all of our elective foot and ankle patients now go to an ultra clean ward (Joint Replacement Unit) and we have shown a reduction in infection rates by over 50% since. Our infection rate before the JRU was 3.3% with 0.7% deep infection rate (818 procedures) and after the introduction of the JRU our infection rate has ped to 1.6% superficial and 0.3% deep infection p<.001.

This large series prospective study sets a benchmark for infection rates in elective foot and ankle surgery. It also highlights the benefit of a dedicated orthopaedic elective unit with rigorous infection control policy and the need to regularly review our results.

This study evaluated the biologic fixation of two different titanium porous coatings: a clinically successful sintered spherical bead coating [1] and a new sintered asymmetric particle coating (STIKTITE™, Smith & Nephew). The spherical bead coating has a porosity of about 50% and an average pore size of about 220 μm, whereas the STIKTITE coating has greater porosity (about 62%) and slightly smaller average pore size (about 200 μm). Biologic fixation was assessed using a load-bearing ovine model in which coated semi-circular disc implants were inserted into a defect created in the cancellous bone parallel to and approximately 3 mm below the medial tibial plateau [2] similar to the method reported by Ignatius [3]. The implants were slightly thicker than the defect created, producing a 0.2-mm overall pressfit. Initial implant stability was assessed using mechanical push-out (n = 3) immediately after implantation into cadaveric ovine bone. Quantitative mechanical push-out testing and qualitative histology (n = 9 and n = 2, respectively, per group per time point) was performed after six and 26 weeks in vivo.

The time-zero average peak push-out load (±S.D.) of the STIKTITE group (95±3 N) was found to be significantly greater (p < 0.02) than that of the spherical bead group (36±5 N). By six weeks in vivo, the average peak push-out load for the STIKTITE group was up to 1001±362 N, and that for the spherical bead group was up to 985±425 N, both representing a significant increase compared to their time-zero results (p < 0.0005). From six to twenty-six weeks in vivo, there was again a significant increase in the peak push-out load irrespective of group (p < 0.0005), with the average peak push-out loads up to 1620±406 N and 1444±446 N for the STIK-TITE and spherical bead groups, respectively. Histology revealed bone ingrowth in both groups that confirmed the findings of the mechanical push-out testing. While the STIKTITE group showed a trend toward greater biologic fixation, overall there was insufficient evidence to support differences between the two groups (p = 0.47) irrespective of the amount of time in vivo.

The results of this study confirm the ability of the STIK-TITE coating to achieve superior initial stability. This improved initial stability reduces the reliance on adjunct fixation (such as screws) or large amounts of press-fit to prevent micromotion and create an environment suitable for long-term bone ingrowth. The results also suggest that the STIKTITE coating had a tendency to initiate and maintain bone ingrowth under load-bearing conditions to a level greater than that of a clinically successful sintered bead coating. Because loading of the implant can cause micromotion at the bone/implant interface, models like the one used in this study likely provide a more challenging and realistic representation of anticipated clinical conditions than models with minimal implant loading.

Introduction: Femoroacetabular impingement (FAI) is an important cause of hip pain in young adults and a precursor to osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis of the hip. From a research perspective, FAI is an example of how subtle morphological abnormality results in a predictable pattern of cartilage damage, and thereby offers great potential as a model to study early degenerative disease.

Although many causes of FAI are described, the vast majority of patients give no history of previous hip disease. The purpose of this study was to investigate the extent to which FAI has an underlying genetic basis, by studying the siblings of patients undergoing surgery for FAI and comparing them with controls.

Methods: 66 patients (probands, 29 male, 37 female, mean age 39.1 years) treated surgically for FAI provided siblings for the study. These patients were classified as having cam, pincer or mixed FAI. 101 siblings (55 male, 56 female, mean age 38.2 years) were recruited. The control group consisted of the 77 partners of those siblings (40 male, 37 female, mean age 41.9 years). All subjects underwent clinical (interview, examination, and hip scores) and radiological assessment (standardised AP Pelvic and cross-table lateral radiographs of each hip). Radiographs were scored for the presence of osteoarthritis, and cam- and pincer-type abnormalities.

Results: Participants were classified as a) Normal morphology with no clinical features, b) Abnormal morphology but no clinical features c) Abnormal morphology with clinical signs but no symptoms, and d) Abnormal morphology with symptoms and signs. The sibling relative risks were significant for groups b, c, and d, supporting the hypothesis of an underlying genetic predisposition to FAI. Siblings usually demonstrated the same type of abnormal morphology as the proband. Gender specificity was apparent however, with pincer abnormalities which were usually apparent in female probands being common in sisters but less common in brothers. The brothers of probands with cam deformities almost universally demonstrated the same deformity, although only 50% of sisters did so.

Discussion: Genetic influences are important in the aetiology of FAI. Whether the morphological abnormality is determined at conception or by an inherited predisposition to an acquired event during maturity warrants further study. We have identified a spectrum of disease with a proportion of siblings with abnormal morphology currently asymptomatic. These cohorts present an opportunity to prospectively study the natural history of the condition, improve our understanding of the mechanisms and pathology in early degenerative disease, and potentially to be recruited into clinical trials of surgical and adjuvant treatments.

We report results using the hydroxyapatite coated, distally locking Cannulok revision hip prosthesis. The component was used to treat periprosthetic and pathological fractures, often in the presence of aseptic loosening or infection in a group of elderly patients. 16 patients with a mean age of 78 years underwent surgery by a single surgeon over a period of 3 years. They were followed up clinically and radiologically for an average of 24 months.

The mean modified Merle D’Aubigne and Oxford Hip Scores were 14 and 23.6 respectively. These results are comparable to the published results for the previous version of the Cannulok hip, and other revision hip revision series.

We believe the implant provides a relatively simple and effective reconstructive option that can be used as an alternative to more extensive surgical options in elderly patients with periprosthetic fractures.