The aim of this study was to assess factors associated with the estimated lifetime risk of revision surgery after primary knee arthroplasty (KA). All patients from the Scottish Arthroplasty Project dataset undergoing primary KA during the period 1 January 1998 to 31 December 2019 were included. The cumulative incidence function for revision and death was calculated up to 20 years. Adjusted analyses used cause-specific Cox regression modelling to determine the influence of patient factors. The lifetime risk was calculated as a percentage for patients aged between 45 and 99 years using multiple-decrement life table methodology.Aims
Methods
The aim of this study was to determine the long-term mortality rate, and to identify factors associated with this, following primary and revision knee arthroplasty (KA). Data from the Scottish Arthroplasty Project (1998 to 2019) were retrospectively analyzed. Patient mortality data were linked from the National Records of Scotland. Analyses were performed separately for the primary and revised KA cohorts. The standardized mortality ratio (SMR) with 95% confidence intervals (CIs) was calculated for the population at risk. Multivariable Cox proportional hazards were used to identify predictors and estimate relative mortality risks.Aims
Methods
The aim of this study was to measure the effect of hospital case-volume on the survival of revision total knee arthroplasty (RTKA). A retrospective analysis of Scottish Arthroplasty Project data was performed. The primary outcome was RTKA survival at ten years. The primary explanatory variable was annual hospital case-volume. Kaplan-Meier survival curves were plotted with 95% confidence intervals (CI) to determine the lifespan of RTKA. Multivariable Cox proportional hazards were used to estimate relative revision risks over time. From 1998 to 2019, 8894 patients underwent RTKA surgery in Scotland (median age 70 years, median follow-up 6.2 years, 4789 (53.5%) females; 718 (8.8%) for infection). Of these patients, 957 (10.8%) underwent a second revision procedure on their knee. Male sex, younger age at index revision, and positive infection status were associated with need for re-revision. The ten-year survival estimate for RTKA was 87.3% (95%CI 86.5–88.1). Adjusting for gender, age, surgeon volume and infection status, increasing hospital case-volume was significantly associated with lower risk of re-revision (Hazard Ratio 0.78 (0.64–0.94, p<0.001)). The risk of re-revision steadily declined in centres performing >20 cases per year: relative risk reduction 16% with >20 cases; 22% with >30 cases; and 28% with >40 cases. The majority of RTKA in Scotland survive up to ten years. Increasing yearly hospital case-volume above 20 cases is independently associated with a significant risk reduction of re-revision. Development of high-volume tertiary centres may lead to an improvement in the overall survival of RTKA.
The aim of this study was to measure the effect of hospital case volume on the survival of revision total knee arthroplasty (RTKA). This is a retrospective analysis of Scottish Arthroplasty Project data, a nationwide audit which prospectively collects data on all arthroplasty procedures performed in Scotland. The primary outcome was RTKA survival at ten years. The primary explanatory variable was the effect of hospital case volume per year on RTKA survival. Kaplan-Meier survival curves were plotted with 95% confidence intervals (CIs) to determine the lifespan of RTKA. Multivariate Cox proportional hazards were used to estimate relative revision risks over time. Hazard ratios (HRs) were reported with 95% CI, and p-value < 0.05 was considered statistically significant.Aims
Methods
The COVID-19 pandemic led to a national suspension of “non-urgent” elective hip and knee arthroplasty. The study aims to measure the effect of the COVID-19 pandemic on total hip arthroplasty (THA) and total knee arthroplasty (TKA) volume in Scotland. Secondary objectives are to measure the success of restarting elective services and model the time required to bridge the gap left by the first period of suspension. A retrospective observational study using the Scottish Arthroplasty Project dataset. All patients undergoing elective THAs and TKAs during the period 1 January 2008 to 31 December 2020 were included. A negative binomial regression model using historical case-volume and mid-year population estimates was built to project the future case-volume of THA and TKA in Scotland. The median monthly case volume was calculated for the period 2008 to 2019 (baseline) and compared to the actual monthly case volume for 2020. The time taken to eliminate the deficit was calculated based upon the projected monthly workload and with a potential workload between 100% to 120% of baseline.Aims
Methods
We compared lower limb coronal alignment measurements
obtained pre- and post-operatively with long-leg radiographs and
computer navigation in patients undergoing primary total knee replacement
(TKR). A series of 185 patients had their pre- and post-implant
radiological and computer-navigation system measurements of coronal alignment
compared using the Bland-Altman method. The study included 81 men
and 104 women with a mean age of 68.5 years (32 to 87) and a mean
body mass index of 31.7 kg/m2 (19 to 49). Pre-implant
Bland–Altman limits of agreement were -9.4° to 8.6° with a repeatability
coefficient of 9.0°. The Bland–Altman plot showed a tendency for the
radiological measurement to indicate a higher level of pre-operative
deformity than the corresponding navigation measurement. Post-implant
limits of agreement were -5.0° to 5.4° with a repeatability coefficient
of 5.2°. The tendency for valgus knees to have greater deformity
on the radiograph was still seen, but was weaker for varus knees. The alignment seen or measured intra-operatively during TKR is
not necessarily the same as the deformity seen on a standing long-leg
radiograph either pre- or post-operatively. Further investigation
into the effect of weight-bearing and surgical exposure of the joint
on the mechanical femorotibial angle is required to enable the most appropriate
intra-operative alignment to be selected.
The humerus is a common site for skeletal metastases in the adult. Surgical stabilisation of such lesions is often necessary to relieve pain and restore function. These procedures are essentially palliative and should therefore provide effective relief from pain for the remainder of the patient’s life without the need for further surgical intervention. We report a retrospective analysis of 35 patients (37 nails) with symptomatic metastases in the shaft of the humerus which were treated by locked, antegrade nailing. There were 27 true fractures (73.0%) and ten painful deposits (27.0%). Relief from pain was excellent in four (11.4%), good in 29 (82.9%) and fair in two (5.7%) on discharge. Function was improved in all but one patient. One case of palsy of the radial nerve was noted. The mean postoperative survival was 7.1 months (0.2 to 45.5) which emphasises the poor prognosis in this group of patients. There were no failures of fixation and no case in which further surgery was required. Antegrade intramedullary nailing is an effective means of stabilising the humerus for the palliative treatment of metastases. It relieves pain and restores function to the upper limb with low attendant morbidity.
Total knee replacement (TKR) has become the standard procedure in management of degenerative joint disease with its success depending mainly on two factors: three dimensional alignment and soft tissue balancing. The aim of this work was to develop and validate an algorithm to indicate appropriate medial soft tissue release during TKR for varus knees using initial kinematics quantified via navigation techniques. Kinematic data was collected intra-operatively for 46 patients with primary end-stage osteoarthritis undergoing TKR surgery using a CT-free navigation system. All patients had preoperative varus knees and medial release was made using the surgeon’s experience. From this data an algorithm was developed to define the medial release based on the pre-operative mechanical femoral-tibial angle with valgus stress; No release (tibial cut only) when valgus stress >
−2/3°. Moderate release (medial aspect of tibia +/− semimembranosous tendon) when valgus stress >
−5° and <
−2°. Extensive release (proximal) when valgus stress <
−5°. If there was a fixed flexion deformity >
5° then a posterior release was performed. This algorithm was validated on a further set of 35 patients where it was used to determine the medial release based only on the kinematic data. The post-operative varus and valgus stress angles for the two groups were compared and showed good outcomes in terms of distribution and outliers. The results showed that the algorithm was a suitable tool to indicate the type of release required based on intra-operatively measured pre-implant valgus stress and extension deficit angles. It reduced the percentage of releases made and the results were more appropriate than the decisions made by an experienced surgeon.
