Aims

The aim of this study was to report the meaningful values of the EuroQol five-dimension three-level questionnaire (EQ-5D-3L) and EuroQol visual analogue scale (EQ-VAS) in patients undergoing primary knee arthroplasty (KA).

Aims

The primary aim was to assess the patient-perceived effect of restrictions imposed due to COVID-19 on rehabilitation following total hip arthroplasty (THA) and total knee arthroplasty (TKA). Secondary aims were to assess perceived restrictions, influence on mental health, and functional outcome compared to patients undergoing surgery without restriction.

Non-surgical osteoarthritis management includes analgesia escalation to oral opiates; however, tolerance can occur. This study aims to assess analgesic effects of opiate use pre-operatively and whether this influences outcome 1-year post-operatively in patients undergoing total hip/knee arthroplasty (THA/TKA).

This prospective study assessed 1487 patients undergoing primary THA (n=729) or TKA (n=758) for osteoarthritis, with 95 respectively reporting pre-operative opiate use >1 month. THA opiate users had significantly higher BMI (p=0.007) and more likely to suffer associated comorbidities. TKA opiate users were significantly younger (p<0.001), with higher BMI (p=0.019) and more likely to suffer associated comorbidities. Pre-operative quality of life (QoL) and joint specific function were significantly worse (Hip EQ-5D 0.17 vs 0.41, p<0.001, OHS 14.6 vs 21.2, p<0.001; Knee EQ-5D 0.27 vs 0.44, p<0.001, OKS 16.4 vs 21.4, p<0.001). Pre-operative pain was significantly worse in those taking opioids (Hip Pain VAS 42.73 vs 50.70, p<0.001; Knee Pain VAS 50.93 vs 53.36, p=0.30). Post-operatively the THA opiate group had significant improvement in EQ-5D (0.175, p<0.001) and OHS (6.5, p<0.001) but were significantly less improved than opiate naïve patients after adjusting for confounding (EQ-5D 0.10, p<0.001; OHS 3.2, p<0.001). TKA opiate group also had significant improvement in EQ-5D (p<0.001) and OKS (p<0.001) but were significantly less (EQ-5D 0.089, p<0.001; OKS 3.9, p<0.001) than opioid naïve patients.

Pre-operative opiate use was associated with significantly worse pre-operative QoL, joint specific function and worse subjective pain. Post-operatively, the opiate group had significantly lower improvement in their QoL and joint specific function.

Aims

The aim of this study was to assess the quality of life of patients on the waiting list for a total hip (THA) or knee arthroplasty (KA) during the COVID-19 pandemic. Secondary aims were to assess whether length of time on the waiting list influenced quality of life and rate of deferral of surgery.

Aims

There are comparatively few randomized studies evaluating knee arthroplasty prostheses, and fewer still that report longer-term functional outcomes. The aim of this study was to evaluate mid-term outcomes of an existing implant trial cohort to document changing patient function over time following total knee arthroplasty using longitudinal analytical techniques and to determine whether implant design chosen at time of surgery influenced these outcomes.

Aims

The EuroQol five-dimension (EQ-5D) questionnaire is a widely used multiattribute general health questionnaire where an EQ-5D < 0 defines a state ‘worse than death’ (WTD). The aim of this study was to determine the proportion of patients awaiting total hip arthroplasty (THA) or total knee arthroplasty (TKA) in a health state WTD and to identify associations with this state. Secondary aims were to examine the effect of WTD status on one-year outcomes.

Aims

To validate the English language Forgotten Joint Score-12 (FJS-12) as a tool to evaluate the outcome of hip and knee arthroplasty in a United Kingdom population.

Objectives

To assess the responsiveness and ceiling/floor effects of the Forgotten Joint Score -12 and to compare these with that of the more widely used Oxford Hip Score (OHS) in patients six and 12 months after primary total hip arthroplasty.

Objectives

The Oxford Hip and Knee Scores (OHS, OKS) have been demonstrated to vary according to age and gender, making it difficult to compare results in cohorts with different demographics. The aim of this paper was to calculate reference values for different patient groups and highlight the concept of normative reference data to contextualise an individual’s outcome.

Total knee arthroplasty (TKA) is an established and successful procedure. However, the design of prostheses continues to be modified in an attempt to optimise the functional outcome of the patient.

The aim of this study was to determine if patient outcome after TKA was influenced by the design of the prosthesis used.

A total of 212 patients (mean age 69; 43 to 92; 131 female (62%), 81 male (32%)) were enrolled in a single centre double-blind trial and randomised to receive either a Kinemax (group 1) or a Triathlon (group 2) TKA.

Patients were assessed pre-operatively, at six weeks, six months, one year and three years after surgery. The outcome assessments used were the Oxford Knee Score; range of movement; pain numerical rating scales; lower limb power output; timed functional assessment battery and a satisfaction survey. Data were assessed incorporating change over all assessment time points, using repeated measures analysis of variance longitudinal mixed models. Implant group 2 showed a significantly greater range of movement (p = 0.009), greater lower limb power output (p = 0.026) and reduced report of ‘worst daily pain’ (p = 0.003) over the three years of follow-up. Differences in Oxford Knee Score (p = 0.09), report of ‘average daily pain’ (p = 0.57) and timed functional performance tasks (p = 0.23) did not reach statistical significance. Satisfaction with outcome was significantly better in group 2 (p = 0.001).

These results suggest that patient outcome after TKA can be influenced by the prosthesis used.

Cite this article: Bone Joint J 2015;97-B:64–70.

Instability is the reason for revision of a primary total knee replacement (TKR) in 20% of patients. To date, the diagnosis of instability has been based on the patient’s symptoms and a subjective clinical assessment. We assessed whether a measured standardised forced leg extension could be used to quantify instability.

A total of 25 patients (11 male/14 female, mean age 70 years; 49 to 85) who were to undergo a revision TKR for instability of a primary implant were assessed with a Nottingham rig pre-operatively and then at six and 26 weeks post-operatively. Output was quantified (in revolutions per minute (rpm)) by accelerating a stationary flywheel. A control group of 183 patients (71 male/112 female, mean age 69 years) who had undergone primary TKR were evaluated for comparison.

Pre-operatively, all 25 patients with instability exhibited a distinctive pattern of reduction in ‘mid-push’ speed. The mean reduction was 55 rpm (sd 33.2). Post-operatively, no patient exhibited this pattern and the reduction in ‘mid-push’ speed was 0 rpm. The change between pre- and post-operative assessment was significant (p < 0.001). No patients in the control group exhibited this pattern at any of the intervals assessed. The between-groups difference was also significant (p < 0.001). This suggests that a quantitative diagnostic test to assess the unstable primary TKR could be developed.

Cite this article: Bone Joint J 2014;96-B:1339–43.

Satisfaction with care is important to both patients and to those who pay for it. The Net Promoter Score (NPS), widely used in the service industries, has been introduced into the NHS as the ‘friends and family test’; an overarching measure of patient satisfaction. It assesses the likelihood of the patient recommending the healthcare received to another, and is seen as a discriminator of healthcare performance. We prospectively assessed 6186 individuals undergoing primary lower limb joint replacement at a single university hospital to determine the Net Promoter Score for joint replacements and to evaluate which factors contributed to the response.

Achieving pain relief (odds ratio (OR) 2.13, confidence interval (CI) 1.83 to 2.49), the meeting of pre-operative expectation (OR 2.57, CI 2.24 to 2.97), and the hospital experience (OR 2.33, CI 2.03 to 2.68) are the domains that explain whether a patient would recommend joint replacement services. These three factors, combined with the type of surgery undertaken (OR 2.31, CI 1.68 to 3.17), drove a predictive model that was able to explain 95% of the variation in the patient’s recommendation response. Though intuitively similar, this ‘recommendation’ metric was found to be materially different to satisfaction responses. The difference between THR (NPS 71) and TKR (NPS 49) suggests that no overarching score for a department should be used without an adjustment for case mix. However, the Net Promoter Score does measure a further important dimension to our existing metrics: the patient experience of healthcare delivery.

Cite this article: Bone Joint J 2014;96-B:622–8.

Objectives

Orthopaedic surgeons use stems in revision knee surgery to obtain stability when metaphyseal bone is missing. No consensus exists regarding stem size or method of fixation. This in vitro study investigated the influence of stem length and method of fixation on the pattern and level of relative motion at the bone–implant interface at a range of functional flexion angles.

Up to 20% of patients are not satisfied with the outcome following total knee replacement (TKR), but little is known about the predictors of this dissatisfaction. This study investigated the pre- and post-operative predictors of dissatisfaction in a large cohort of patients undergoing TKR. We assessed 1217 consecutive patients undergoing TKR between 2006 and 2008 both preoperatively and six months after surgery, using the Short-form (SF)-12 health questionnaire and the Oxford Knee Score.

Detailed co-morbidity information was also gathered. Satisfaction was measured at one year and 18.6% (226 of 1217) of patients were unsure or dissatisfied with their replacement, 81.4% (911 of 1217) were satisfied or very satisfied. Multivariate regression analysis was performed to identify independent predictors of dissatisfaction. Significant (p < 0.001) predictors of dissatisfaction at one year included the pre-operative SF-12 mental component score, the co-morbidities of depression and pain in other joints, and the six-month SF-12 score. The most significant independent predictor of dissatisfaction at 1 year was poor improvement in Oxford Knee Score pain element at 6 months. Patient expectations were highly correlated with satisfaction.

Satisfaction following TKR is multifactorial. Managing patient expectations and mental health may reduce dissatisfaction rates. However, the most significant predictor of dissatisfaction is a painful total knee replacement.

Study Aim

Femoral components used in total knee arthroplasty (TKA) are primarily designed on the basis of kinematics and ease of fixation. This study considers the stress-strain environment in the distal femur due to different implant internal geometry variations (based on current industry standards) using finite element (FE) analyses. Both two and three dimensional models are considered for a range of physiological loading scenarios – from full extension to deep flexion. Issues associated with micro-motion at the bone-implant interface are also considered.

Introduction: Instability after total hip arthroplasty is an important complication. It commonly occurs in the immediate postoperative period, but the risk is reported to continue over time. There are numerous surgical treatment options, but they have relatively unpredictable outcomes. Numerous factors have been associated with dislocation, but research has mainly focused on surgical factors. Epidemiological factors remain the subject of much debate. We aimed to establish the incidence of dislocation over time.

Methods: The Scottish National arthroplasty non-voluntary registry is based on SMR01 records (Scottish Morbidity Record) data. We analyzed the Scottish National Arthroplasty Project to find patients’ dislocation rates up to 12 years post surgery.

Results: There were 62,175 total hip arthroplasties performed from April 1989 to March 2004 with an annual incidence of dislocation of 0.9%. The majority of dislocations occur by 12 months (66%) but patients remain at relatively high risk even after the first 3 months by when only 23% of the total have occurred. We found no increase in the rate of dislocation after 2 years.

Discussion: Patients should be warned that the risk of dislocation remains for the first year. However, it appears there is no late increase in dislocation rate associated with wear and declining mental or muscle function.

The aim of the study is to investigate the biomechanical effects on the pelvis of the anterolateral and posterolateral approaches at the time of hip arthroplasty. In particular the study investigates the change in stress distribution, and the change in muscle recruitment pattern following surgery.

The study uses an advanced finite element model of the pelvis, in which the role of muscles and ligaments in determining the stress distribution in the pelvis is included. The model is altered for the posterolateral approach by excision of the external rotators. Different levels of gluteal damage for the anterolateral approach are modelled by excising in turn the anterior third, half, and two-thirds of the gluteus medius and minimus. Although attempt is generally made to repair gluteal damage at the time of surgery, it is clear the muscle volume will be compromised immediately after surgery.

In support of previous clinical studies indicating an increased risk of limp, and pelvic tilt following the anterolateral approach, significant differences were found in the muscle recruitment pattern following the anterolateral, compared to the posterolateral approach. During single leg stance and walking force transfer to the iliacus and pectineus was observed. Required levels of muscle force, to maintain coronal balance, following the anterolateral approach were found to be close to maximum sustainable levels. In addition significant alteration to the pelvic stress distribution was found following the anterolateral approach. The effects of increasing gluteal damage for the anterolateral approach were progressive, and became more pronounced when more than fifty percent of the gluteus medius and minimus were damaged. Increases in stresses around the acetabulum were observed for the posterolateral, compared to the anterolateral approach.

Thus, based on a biomechanical evaluation, the anterolateral approach presents increased risk of limp, and pelvic tilt, in comparison to the posterolateral approach.

Aim: To investigate the incidence and type of venous thromboembolic event (VTE) diagnosed in patients undergoing total knee arthroplasty (TKA) and the trends over time following the introduction of a rigorously enforced thromboprophylaxis protocol.

Methods: Data from all 3260 TKAs performed in our unit between April 1996 and March 2003 were prospectively collected by the Scottish Arthroplasty Project (SAP). The SAP data identified 84 of these patients as having being admitted with or died from a VTE episode. A unified thromboprophylaxis protocol was introduced in 1999, from 2001 it was included as part of the integrated care pathway. We retrospectively reviewed all available casenotes of these patients to identify the assessment and thromboprophylaxis given, the precise diagnosis of VTE, the treatment and adverse outcomes.

Results: Of the 84 VTEs identified, 29 had pulmonary emboli (PE), 12 had above knee deep vein thrombosis (DVT), 24 had calf DVT and 10 had no evidence of VTE though were coded as such (but not treated) by physicians elsewhere. Data were unavailable for the remaining 9 but these were assumed to have had VTE for the purposes of this study. Of the 24 patients with calf only DVT, 16 were given therapeutic anticoagulation of whom five developed haemorrhagic complications. From 2001 the thromboprophylaxis protocol was followed in 100% of patients. The rate of VTE in our unit has fallen steadily from 2.26% in 1996–7 to 1.05% in 2002–3.

Conclusions: There has been a steady decline in the rate of venous thromboembolism in our unit over the seven years of the study. A thromboprophylaxis protocol has been successfully introduced in our unit and consistently applied since 2001. There is considerable overdiagnosis and treatment of calf DVT with significant resultant morbidity.

Introduction: Instability after total hip arthroplasty is an important complication. Instability usually occurs in the immediate postoperative period, but the risk also increases with time. There are numerous surgical treatment options, but they have relatively unpredictable outcomes. Numerous factors are associated with dislocation, but research has mainly focused on surgical factors. Epidemiological factors remain the subject of much debate. The aim of this study was to find any such factors significantly associated with dislocation.

Methods: The Scottish National arthroplasty non-voluntary registry is based on SMR01 records (Scottish Morbidity Record) data. We analyzed the Scottish National Arthroplasty Project to find patients’ dislocation rates up to 1 year postoperatively for age, surgeon volume, gender, previous surgery, diagnosis, and follow-up duration.

Results: There were 14,314 total hip arthroplasties performed from April 1996 to March 2004. Two hundred sixty-six dislocations occurred for an average annual incidence of 1.9%. There was an association between rate of dislocation with age, surgical volume, and previous fracture. However, there was no increase in the rate of dislocation associated with gender or with diagnoses of stroke or Parkinson’s disease.

Discussion: Statistical analysis of large databases allows identification of the most relevant factors. There is a surprisingly low incidence of THA dislocation in patients with neurological conditions. This epidemiological data allows prognostic assessment of the risk of dislocation for individual patients. From this strategies can be employed to reduce the chance of dislocation in high-risk patients.