Birmingham Metal-on-metal total hip resurfacing (BHR) is a bone-conserving option for patients with advanced articular damage. While the outcomes of Total Hip Replacement (THR) are well documented, there is a paucity of literature comparing the patient reported outcomes of BHR versus THR. This study aims to compare the patient reported outcomes for an impact on quality of life between patients who had a BHR vs. THR after correcting for selection bias. Patients who underwent a BHR or THR between July 2003 and December 2006 were included. Patient questionnaires included demographic details, co-morbidities, WOMAC, SF-36 Scores. In addition, a 4 point Likert scale was used to measure satisfaction post-operatively. The above data was collected pre-operatively and at 1, 2, 3 and 5 years post-operatively. Data was analysed with SPSS (version 19) software package. All analysis was adjusted for Age, gender, Co-morbidity and pre-operative score by using Multivariate regression analysis using a General Liner Model to rule out the effect of these predictors on outcomes between groups. 337 patients were included (205 for THR and 132 for BHR). BHR patients were younger than THR patients (49 vs. 67 years, p<0.01), were more likely to be male (68% vs. 42% of THR, p<0.01), reported fewer co-morbidities (1.06 vs. 1.59, p<0.01). BHR patients reported better WOMAC pain and function scores at 5 years (p<0.05). For SF-36 scores, BHR patients reported higher scores for all 8 domains at 1 year and 5 year follow up (p<0.05). BHR patients reported higher satisfaction than THR group for return to Activities of Daily Living and Recreational activities at 1 and 5 years (p<0.05) After correction for patient variability, BHR patients reported better improvement in pain and function and enjoyed a better quality of life in relation to return to ADL and recreational activities over to 5 years post-surgery.
Cemented stems have shown 90–100% survivorship when coupled with polyethylene acetabular component. This study aims to compare cemented stem behaviour in combination with large metal on metal (MOM) vs. metal on poly (MOP) bearings. 100 patients were recruited into a single centre RCT (we required 40 in each group for power .90 to confirm stem subsidence of >0.5mm at 2 years; p< 0.05). Recruits were randomized to MOP (28mm) or MOM femoral heads with CPCS cemented femoral stem. Assessments included X-rays (AP pelvis), Harris Hip Scores, blood metal ion levels and patient questionnaires (WOMAC, SF-36, satisfaction questionnaire). Evaluations were done pre-operatively and 3, 12 and 24 months post operatively; blood metal ion measures at 1 year.Introduction
Patients and Methods
This project reports differences in outcome measures after total ankle arthroplasty (TAA) for patients with Osteoarthritis (OA), Rheumatoid Arthritis (RA) and Post-traumatic Osteoarthritis (PTOA). Patients who underwent TAA between March 2006 and May 2010 were included. Assessments including questionnaires (height, weight, Foot and Ankle Outcome Score, SF-36) and American Orthopaedic Foot and Ankle Score (AOFAS) were completed pre-operatively, 3, 6, and 12-months after surgery. Analyses of outcomes by diagnosis were adjusted for age, gender and BMI.Introduction
Materials and Methods
Peri prosthetic fracture is a recognised complication following Total ankle arthroplasty (TAA). There is limited literature on post operative management following TAA and controversies exist based on surgeon preferences. This project reports the incidence of peri- prosthetic fractures in patients managed with 2 different post-operative protocols. Patients undergoing primary TAA with a diagnosis of Osteoarthritis (OA) or Post-traumatic Osteoarthritis (PTOA) were recruited into a randomized controlled trial. These patients did not require any additional procedures. Patients were consented for the trial and randomized to one of two treatment groups (Early mobilisation after surgery vs. immobilisation in a plaster cast for 6 weeks post operatively). Plaster group patients underwent a graduated physiotherapy program from 6-12 weeks and early mobilisation group patients from 1-12 weeks. Complications any were recorded at 2, 4, 6 and 12 weeks post-operatively.Introduction
Materials and Methods
We aimed to identify whether patients in lower socioeconomic groups had worse function prior to total knee arthroplasty and to establish whether these patients had worse post-operative outcome following total knee arthroplasty. Data were obtained from the Kinemax outcome study, a prospective observational study of 974 patients undergoing primary total knee arthroplasty for osteoarthritis. The study was undertaken in thirteen centres, four in the United States, six in the United Kingdom, two in Australia and one in Canada. Pre-operative data were collected within six weeks of surgery and patients were followed for two years post-operatively. Pre-operative details of the patient's demographics, socioeconomic status (education and income), height, weight and co-morbid conditions were obtained. The WOMAC and SF-36 scores were also obtained. Multivariate regression was utilised to analyse the association between socioeconomic status and the patient's pre-operative scores and post-operative outcome. During the analysis, we were able to control for variables that have previously been shown to effect pre-operative scores and post-operative outcome. Patients with a lower income had a significantly worse pre-operative WOMAC pain (p=0.021) and function score (p=0.039) than those with higher incomes. However, income did not have a significant impact on outcome except for WOMAC Pain at 12-months (p=0.014). At all the other post-operative assessment times, there was no correlation between income and WOMAC Pain and WOMAC Function. Level of education did not correlate with pre-operative scores or with outcome at any time during follow-up. This study demonstrates that across all four countries, patients with lower incomes appear to have a greater need for total knee arthroplasty. However, level of income and educational status did not appear to affect the final outcome following total knee arthroplasty. Patients with lower incomes appear able to compensate for their worse pre-operative score and obtain similar outcomes post-operatively.
Total Ankle Arthroplasty (TAA) using the uncemented three component mobile design has shown encouraging results. There is limited literature on the optimal postoperative management. In our centre, TAA patients are mobilised 48 hours after surgery without a short leg plaster. The aim of this prospective audit was to measure the outcomes of these patients to ascertain if this is a safe and effective protocol. Patients who underwent primary TAA between March 2006 and March 2008 were invited to participate in the audit. Assessment included patient questionnaires which collected demographics, height and weight, Foot and Ankle Outcome Score (FAOS) and Short-Form-36 (SF-36). Clinical examination collected American Orthopaedic Foot and Ankle Score (AOFAS). Data was collected pre-operatively and at 3 and 6 months after surgery. A total of 48 ankle replacements in 46 patients were included. Primary diagnosis was osteoarthritis (25), post-traumatic osteoarthritis (9), and rheumatoid arthritis (12). Mean age was 63 years (range 33 to 83) and the majority were males (29, 60%). The average body mass index was 28 (SD 5.3). There were significant improvements to 3-months after surgery for AOFAS (mean 29 to 76, p<
0.0001), FAOS (mean scores changes: Pain 36 to 72, Function 41 to 68, Stiffness 38 to 65, p<
0.001) and physical domains of the SF-36 (means score changes: Physical Functioning 25 to 39, Role Physical 27 to 40, Bodily Pain 29 to 48 and Vitality 42 to 50, p<
0.05). All outcome scores were maintained with a non-significant trend for better scores from 3 to 6 months. These early results demonstrate encouraging outcomes for TAA patients who are mobilised early after surgery without a short leg plaster. Further studies of post-operative management are needed to compare outcomes after TAA between patients undergoing this protocol and patients who are immobilised in plaster.
We have attempted to quantify the influence of clinical, radiological and prosthetic design factors upon flexion following knee replacement. Our study examined the outcome following 101 knee replacements performed in two prospective randomized trials using similar cruciate retaining implants. Multivariate analyses, after adjusting for age, sex, diagnosis and the type of prosthesis revealed that the only significant correlates for range of movement at 12-months were the difference in posterior condylar offset ratio (p<
0.001), tibial slope (p<
0.001) and preoperative range of movement (p=0.025). We found a moderate correlation between 12-month range of movement and posterior tibial slope (R=0.58) and the difference of post femoral condylar offset (that is, post-operative minus preoperative posterior condylar offset, R=0.65). Posterior condylar offset had the greatest impact upon final range of movement highlighting this as an important consideration for the operating surgeon at pre-operative templating when choosing both the design and size of the femoral component.
We aimed to identify whether patients in lower socioeconomic groups had worse function prior to total knee arthroplasty and to establish whether these patients had worse post-operative outcome following total knee arthroplasty. Data was obtained from the Kinemax outcome study, this was a prospective observational study of 974 patients undergoing primary total knee arthroplasty for osteoarthritis. The study was undertaken in thirteen centers, four in the United States, six in the United Kingdom, two in Australia and one in Canada. Pre-operative data was collected within six weeks of surgery and patients were followed for two years post-operatively. Pre-operative details of the patient’s demographics, socioeconomic status (education and income), height, weight and co-morbid conditions were obtained. The WOMAC and SF-36 scores were also obtained. Multivariate regression was utilised to analyse the association between socioeconomic status and the patient’s pre-operative scores and post-operative outcome. During the analysis, we were able to control for variables that have previously been shown to effect pre-operative scores and post-operative outcome. Patients with a lower income had a significantly worse pre-operative WOMAC pain (p=0.021) and function score (p=0.039) than those with higher incomes. However, income did not have a significant impact on outcome except for WOMAC Pain at 12-months (p=0.014). At all the other post-operative assessment times, there was no correlation between income and WOMAC Pain and WOMAC Function. Level of education did not correlate with pre-operative scores or with outcome at any time during follow-up. This study demonstrates that across all four countries, patients with lower incomes appear to have a greater need for total knee arthroplasty. However, level of income and educational status did not appear to effect the final outcome following total knee arthroplasty. Patients with lower incomes appear able to compensate for their worse pre-operative score and obtain similar outcomes post-operatively.
This study aimed to determine the prevalence of osteoporosis in patients awaiting hip and knee replacement for osteoarthritis and to review them two years later to determine the changes in bone density following joint replacement. Patients aged between 65 and 80 years awaiting total hip or knee replacement were invited to participate. Lumbar spine, bilateral femoral and forearm bone mineral density (BMD) measurements were obtained using dual energy x-ray absorptiometry. BMD values were standardised using previously published T-scores and Z-scores. To assess clinical status, patients completed a questionnaire including the Western Ontario and McMaster University OA Index (WOMAC). All measurements were repeated at two-years. Participants included 199 patients (84 hips and 115 knees) with a mean age of 72 years (SD 4.0) and were predominantly female (hips 67%, knees 50%). At baseline 46/199 (23%) patients (39 females) had evidence of osteoporosis (WHO definition) at one or more sites with the highest prevalence at the forearm (14%). At two-years 144 patients attended for review with 128 having undergone hip (56) or knee (72) replacement. At this review 39/144 (27%) patients (33 females) had evidence of osteoporosis at one or more sites with the highest prevalence at the forearm (22%). The greatest bone loss occurred at the forearm with median BMD change of minus 4% for females (25th percentile minus 7.3%, 75th percentile minus 1.9%) and minus 2.9% for males (25th percentile minus 4.6%, 75th percentile minus 1.1%). There was a significant difference in WOMAC Pain scores at follow-up between the osteo-porotic and non-osteoporotic knee patients (67 versus 81, p=0.002) indicating that osteoporotic patients had greater knee pain. We have identified the forearm as not only the site with the highest prevalence of osteoporosis but also the greatest bone loss at follow-up. Further evaluation of forearm bone density measurements in the preopera-tive assessment and follow-up of patients awaiting joint replacement for hip and knee OA is required. Larger studies are needed to confirm our finding that the presence of osteoporosis is predictive of worse patient-reported outcomes of knee replacement.
37 patients were suspected clinically of having a deep venous thrombosis, 10 of which were confirmed radiologically, giving a rate of 4%. Nine patients had a suspected pulmonary embolism, 2 of which were confirmed radiologically and one of whom died of pulmonary embolism, giving an overall rate of fatal pulmonary embolism of 0.4%. All patients with thromboembolic events had lower extremity tumours and all were surgical patients. However, the majority of thromboembolic events (6 of 10 deep venous thromboses and 2 of 3 pulmonary embolisms) occurred prior to surgery.
This paper aims to determine if preoperative characteristics have a significant impact on functional outcome as measured by the WOMAC at 2-years following total knee replacement (TKR) surgery. Patients were recruited as part of a prospective study of outcomes of primary TKR for osteoarthritis in centres in the US (4 centres), UK (6 centres) and Australia (2 centres). Research assistants recruited eligible patients and collected clinical history and physical examination data preoperatively, 3, 12 and 24-months post surgery. The WOMAC, SF-36, patients satisfaction and demographic data were obtained by self-administered questionnaires. All scores were transformed to 0–100 scale (100 best). We recruited 860 eligible patients and have complete 12-month WOMAC data on 736 patients (86%) and 2-year data on 701 patients (78%). Mean age was 70 years (SD 10), 59% were female, 50% were from the UK, 30% from the US and 20% from Australia. Mean preoperative clinical measures were: knee flexion 107° (SD18), SF36 Mental Health 72 (SD19), body mass index 29 (SD 6) and WOMAC Function 45 (SD 19). 46% of patients reported more than 2 comorbid conditions. There was no significant difference between mean WOMAC Function scores at 12-months (73, SD 21) and 2-years (74, SD21). In a linear regression model (model R- square= 25), the preoperative predictors of worse WOMAC Function at 2-years, in order of decreasing importance, were: low WOMAC Function (p<
0.0001), higher number of comorbid conditions (p=0.0002), UK patients (p=0.0002), low SF36 Mental Health (p=0.01) and restricted preoperative knee flexion (p=0.02). Patients who come to surgery with poor function, restricted knee flexion, low mental health and other comorbid conditions are more likely to have worse functional outcomes 2-years following surgery. After adjusting for these predictors, the UK patients had significant lower WOMAC Function scores than the US and Australia.
Presently, many instruments exist for assessing both patient - and surgeon-based satisfaction after joint replacement, including both generic (measures of general health status) and disease specific measures. As such, the US PORT study (1995) recommends use of both the WOMAC and SF-36. However, this means that studies need to incorporate at least these two lengthy questionnaires into protocols, which increases the pressure on patients for both time and difficulty, but also introduces some duplication of data. The SF-36 has been successfully reduced and validated to a 12 item questionnaire (SF-12) which can be used as a summarised generic health score. It would be of great benefit if a reduced version of the WOMAC could be derived to give a similar summarised disease-specific measurement tool. To derive and assess the validity of a reduced function scale of the WOMAC for patients with osteoarthritis of the hip and knee. All unilateral data from 12 centres world-wide (UK US Canada and Australia) involved in an international, multi-centre outcome study for patients undergoing TKR were included for analysis. The reduced scale was derived from pre-op and 3 month post op data using a combination of data-driven analysis and purely clinical methods. The reduced WOMAC was then extensively validated in three key areas; validity, reliability and responsiveness using 12 month post-op data from the study and data from the Medicare Hip Replacement Study. Data from 898 patients pre-operatively and 806 patients at 3-months were used for the data driven section of analysis. For the clinical section, 30 members of the orthopaedic community were surveyed as to their opinions of which items should be retained in the reduced version of the scale. These results were then combined to produce a reduced function scale of 7 items to be used in conjunction with the 5-item pain scale. The questions remaining in the scale (and their original number in the scale) were: 2) ascending stairs, 3) rising from sitting, 6) walking on flat, 7) getting in/out of car, 9) putting on socks/stockings, 10) rising from bed and 14) sitting. This reduced scale was then scrutinised to ensure it’s validity (both construct and content), reliability (both internal consistency and reproducibility) and responsiveness (using Standardised Response Means). When examining 12 month data the reduced scale compared favourably with the full scale both overall, and when sub-divided by age, sex and country. It’s construct validity was confirmed by significant positive correlation with the SF-36 physical component score, the knee society function score, the Oxford knee score, and for the hip data, the Harris hip score and SF-12 physical component score. Cronbach’s alpha was consistently high (α>
0.85) with the reduced scale, showing it to be reliable, and the SRM’s indicated that the reduced scale may even be better at detecting change than the full scale. This reduced WOMAC has been successfully derived and validated for use as a summarised and more practical version of the full WOMAC scale.