The Oxford hip score: the patient's perspective

BACKGROUND: In the last 25 years, assessment of orthopaedic intervention has become patient focused, with the development of self-completion patient-centred outcome measures. The Oxford hip score (OHS) is a joint specific outcome measure tool designed to assess disability in patients undergoing total hip replacement (THR). Although the psychometric properties of the OHS have been rigorously examined, there is little research on the patient's perspective of the OHS. Therefore, the aim of this study is to assess whether the OHS is an adequate disability measure from the patient's perspective using qualitative analysis of annotations written on the OHS by patients. METHODS: In total, 276 orthopaedic patients completed an OHS between April 2004 and May 2005. One hundred and fifty six pre-operative patients listed for a THR completed the OHS during a pre-admission assessment clinic, and 120 post-operative patients completed the OHS postally in the home setting. Patient's unprompted annotations in response to the questions on the OHS were recorded and grouped into thematic categories. RESULTS: In total, 46 (17%) patients made 52 annotations when completing the OHS. These annotations identified five main areas of difficulty that patients experienced: lack of question clarity (particularly concerning the use of aids), difficulty in reporting measurements of pain, restrictive and irrelevant questions, the influence of co-morbidities on responses, and double-barrelled questions. CONCLUSION: Although the OHS is a useful short tool for the assessment of disability in patients undergoing THR, this study identified several problem areas that are applicable to patient-centred outcome tools in general. To overcome these current limitations, further work is underway to develop a more individualised patient-centred outcome measure of disability for use in patients with osteoarthritis

Antibiotic additives alter the static and viscoelastic properties of bone cements

Introduction: In arthroplasty antibiotics are added to bone cements to prevent deep infection. The static properties of plain and antibiotic laden cements have been extensively described in the literature [1]. Commercially available cements must perform above the minimum values set by ISO 5833:2002 [2]. However, no upper or lower limits are set for the viscoelastic properties of the cements, despite this being a recognised factor affecting the cement-implant performance [3]. The ability of acrylic bone cement to creep and stress relax in conjunction with forceclosed stems in hip arthroplasty affords protection of the vital bone-cement interface. With this design subsidence of the stem within the cement mantle over time does not lead to clinical failure [4]. Conversely, the clinical performance of shapeclosed stem designs can be negatively affected by cements demonstrating excessive creep. This study investigated the effect of antibiotic additives on the static and viscoelastic properties of PMMA cement. Materials and Methods: The mechanical and viscoelastic properties of Simplex P, Simplex Antibiotic and Simplex Tobramycin (Stryker, Limerick, IE) were investigated. This family of cements was chosen as they are characterised by the same polymeric base, that of Simplex P, the plain formulation, but contain different antibiotic additives. In particular Simplex Antibiotic contains 0.5g Erythromycin and 3 million I.U. Colistin, while in Simplex Tobramycin the only additive is 0.5g of Tobramycin. The static properties of the cements (compressive strength, bending strength and bending modulus) were assessed following ISO 5833:2002 [2], while stress relaxation and creep were assessed under quasi static conditions in a four pointbending configuration. The creep experiments were carried out using a custom made apparatus with the specimens positioned in a distilled water bath at 37 o

A new short uncemented, proximally fixed anatomic femoral implant with a prominent lateral flare: design rationals and study design of an international clinical trial

<p>Abstract</p> <p>Background</p> <p>Anatomic short femoral prostheses with a prominent lateral flare have the potential to reduce stress-shielding in the femur through a more physiological stress distribution to the proximal femur. We present the design rationale of a new short uncemented, proximally fixed anatomic femoral implant and the study design of a prospective multi-centre trial to collect long-term patient outcome and radiographic follow up data.</p> <p>Methods</p> <p>A prospective surveillance study (trial registry NCT00208555) in four European centres (UK, Italy, Spain and Germany) with a follow up period of 15 years will be executed. The recruitment target is 200 subjects, patients between the ages of 18 and 70 admitted for primary cementless unilateral THA will be included. The primary objective is to evaluate the five-year survivorship of the new cementless short stem. The secondary objectives of this investigation are to evaluate the long term survivorship and the clinical performance of the implant, the impact on the subjects health related Quality of Life and the affect of the prosthesis on bone mineral density. Peri- and postoperative complications will be registered. Clinical and radiographic evaluation of prosthesis positioning will be done post-operatively and at 3, 6, 12, 24, 60, 120 and 180 months follow up.</p> <p>Discussion</p> <p>Shortening of the distal stem can maximise bone and soft tissue conservation. New stem types have been designed to improve the limitations of traditional implants in primary THA. A new, uncemented femoral short stem is introduced in this paper. A long-term follow up study has been designed to verify stable fixation and to research into the clinical outcome. The results of this trial will be presented as soon as they become available.</p

Periprosthetic DXA after total hip arthroplasty with short vs. ultra-short custom-made femoral stems

Background and purpose Dual-energy X-ray absorptiometry (DXA) analysis of the 7 periprosthetic Gruen zones is the most commonly used protocol to evaluate bone remodeling after the implantation of conventional femoral stems. We assessed the value of DXA after cementless primary total hip arthroplasty (THA) by comparing the effect of progressive shortening of the stem of two femoral implants on periprosthetic bone remodeling using a specifically developed protocol of analysis with 5 periprosthetic regions of interest (ROIs)

Impaction bone grafting of the acetabulum at hip revision using a mix of bone chips and a biphasic porous ceramic bone graft substitute: Good outcome in 43 patients followed for a mean of 2 years

Background and purpose One of the greatest problems of revision hip arthroplasty is dealing with lost bone stock. Good results have been obtained with impaction grafting of allograft bone. However, there have been problems of infection, reproducibility, antigenicity, stability, availability of bone, and cost. Thus, alternatives to allograft have been sought. BoneSave is a biphasic porous ceramic specifically designed for use in impaction grafting. BoneSave is 80% tricalcium phosphate and 20% hydroxyapatite. Previous in vitro and in vivo studies have yielded good results using mixtures of allograft and BoneSave, when compared with allograft alone. This study is the first reported human clinical trial of BoneSave in impaction grafting

Unstated factors in orthopaedic decision-making: a qualitative study

<p>Abstract</p> <p>Background</p> <p>Total joint replacement (TJR) of the hip or knee for osteoarthritis is among the most common elective surgical procedures. There is some inequity in provision of TJR. How decisions are made about who will have surgery may contribute to disparities in provision. The model of shared decision-making between patients and clinicians is advocated as an ideal by national bodies and guidelines. However, we do not know what happens within orthopaedic practice and whether this reflects the shared model. Our study examined how decisions are made about TJR in orthopaedic consultations.</p> <p>Methods</p> <p>The study used a qualitative research design comprising semi-structured interviews and observations. Participants were recruited from three hospital sites and provided their time free of charge. Seven clinicians involved in decision-making about TJR were approached to take part in the study, and six agreed to do so. Seventy-seven patients due to see these clinicians about TJR were approached to take part and 26 agreed to do so. The patients' outpatient appointments ('consultations') were observed and audio-recorded. Subsequent interviews with patients and clinicians examined decisions that were made at the appointments. Data were analysed using thematic analysis.</p> <p>Results</p> <p>Clinical and lifestyle factors were central components of the decision-making process. In addition, the roles that patients assigned to clinicians were key, as were communication styles. Patients saw clinicians as occupying expert roles and they deferred to clinicians' expertise. There was evidence that patients modified their behaviour within consultations to complement that of clinicians. Clinicians acknowledged the complexity of decision-making and provided descriptions of their own decision-making and communication styles. Patients and clinicians were aware of the use of clinical and lifestyle factors in decision-making and agreed in their description of clinicians' styles. Decisions were usually reached during consultations, but patients and clinicians sometimes said that treatment decisions had been made beforehand. Some patients expressed surprise about the decisions made in their consultations, but this did not necessarily imply dissatisfaction.</p> <p>Conclusions</p> <p>The way in which roles and communication are played out in decision-making for TJR may affect the opportunity for shared decisions. This may contribute to variation in the provision of TJR. Making the importance of these factors explicit and highlighting the existence of patients' 'surprise' about consultation outcomes could empower patients within the decision-making process and enhance communication in orthopaedic consultations.</p

A comparison of the survival of total hip replacement inserted over two sequential time periods

Modifications in design and surgical technique have been directed at improving the long-term survival of total hip replacement. This study examines the failure rate, with revision as endpoint, of two large cohorts of primary total hip replacement carried out over consecutive six-year intervals. The intention of the study was not to compare specific prostheses or techniques, but to examine failure rates between two time periods which embraced significant changes of practice. At one specialised centre in Bristol, 2747 primary total hip replacements were performed between 1980 and 1986. Seventy-six failed within 5 years (2.8%) with 23 of these failing in the first year (0.8%). Between 1987 and 1992, 3232 primary total hip replacements were carried out, with 98 hips requiring revision within 5 years (3.0%), 21 of these in the first year (0.6%). There was no statistical difference in the incidence of failure between these two time periods; however, the failure rate for the more recent time period was marginally higher. This indicates that although techniques and prosthetic design have changed significantly, the anticipated reduction in incidence of failure has not materialised. There is undoubtedly a need for ongoing review to ensure that changes in technique and component design are producing the desired long-term effect

Somatosensory abnormalities in knee OA

Objective: The aim of this study was to use quantitative sensory testing (QST) to explore the range and prevalence of somatosensory abnormalities demonstrated by patients with advanced knee OA. Methods: One hundred and seven knee OA patients and 50 age- and sex-matched healthy participants attended a 1-h QST session. Testing was performed on the medial side of the knee and the pain-free forearm. Light-touch thresholds were assessed using von Frey filaments, pressure pain thresholds using a digital pressure algometer, and thermal sensation and pain thresholds using a Thermotest MSA. Significant differences in median threshold values from knee OA patients and healthy participants were identified using Mann-Whitney U-tests. The z-score transformations were used to determine the prevalence of the different somatosensory abnormalities in knee OA patients. Results: Testing identified 70% of knee OA patients as having at least one somatosensory abnormality. Comparison of median threshold values between knee OA patients and healthy participants revealed that patients had localized thermal and tactile hypoaesthesia and pressure hyperalgesia at the osteoarthritic knee. Tactile hypoaesthesia and pressure hyperalgesia were also present at the pain-free forearm. The most prevalent somatosensory abnormalities were tactile hypoaesthesia and pressure hyperalgesia, evident in between 20 and 34% of patients. Conclusion: This study found that OA patients demonstrate an array of somatosensory abnormalities, of which the most prevalent were tactile hypoaesthesia and pressure hyperalgesia. Further research is now needed to establish the clinical implications of these somatosensory abnormalities. © The Author 2011. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved

Persistent pain after joint replacement: Prevalence, sensory qualities, and postoperative determinants

Persistent postsurgical pain is a prevalent but underacknowledged condition. The aim of this study was to assess the prevalence, sensory qualities, and postoperative determinants of persistent pain at 3 to 4 years after total knee replacement (TKR) and total hip replacement (THR). Patients completed a questionnaire with included the Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC) Pain Scale, PainDetect Questionnaire, Short-Form McGill Pain Questionnaire, and questions about general health and socioeconomic status. A total of 632 TKR patients and 662 THR patients completed a questionnaire (response rate of 73%); 44% of TKR patients and 27% of THR patients reported experiencing persistent postsurgical pain of any severity, with 15% of TKR patients and 6% of THR patients reporting severe-extreme persistent pain. The persistent pain was most commonly described as aching, tender, and tiring, and only 6% of TKR patients and 1% of THR patients reported pain that was neuropathic in nature. Major depression and the number of pain problems elsewhere were found to be significant and independent postoperative determinants of persistent postsurgical pain. In conclusion, this study found that persistent postsurgical pain is common after joint replacement, although much of the pain is mild, infrequent, or an improvement on preoperative pain. The association between the number of pain problems elsewhere and the severity of persistent postsurgical pain suggests that patients with persistent postsurgical pain may have an underlying vulnerability to pain. A small percentage of patients have severe persistent pain after joint replacement, and this is associated with depression and the number of pain problems elsewhere. © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved