Aims. Responsiveness to clinically important change is a key feature of any outcome measure. Throughout Europe, health-related quality of life following total knee arthroplasty (TKA) is routinely measured with EuroQol five-dimension (EQ-5D) questionnaires. The Patient-Reported Outcomes Measurement Information System 10-Question Short-Form (PROMIS-10 Global Health) score is a new general heath outcome tool which is thought to offer greater responsiveness. Our aim was to compare these two tools. Patients and Methods. We accessed data from a prospective multicentre cohort study in the United Kingdom, which evaluated outcomes following TKA. The median age of the 721 patients was 69.0 years (interquartile range, 63.3 to 74.6). There was an even division of sex, and approximately half were educated to secondary school level. The preoperative EQ-5D, PROMIS-10, and Oxford Knee Scores (OKS) were available and at three, six, and 12 months postoperatively. Internal responsiveness was assessed by standardized response mean (SRM) and effect size (Cohen’s d). External responsiveness was assessed by correlating change scores of the EQ-5D and PROMIS-10, with the minimal clinically important difference (MCID) of the
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. Patients and Methods. A cross-sectional analysis of 2073 patients undergoing 2073 THAs (mean age 67.4 years (. sd. 11.6; 14 to 95); mean body mass index (BMI) 28.5 kg/m. 2. (. sd. 5.7; 15 to 72); 1253 female (60%)) and 2168 patients undergoing 2168 TKAs (mean age 69.3 years (. sd. 9.6; 22 to 91); BMI 30.8 kg/m. 2. (. sd. 5.8; 13 to 57); 1244 female (57%)) were recorded. Univariate analysis was used to identify variables associated with an EQ-5D score < 0: age, BMI, sex, deprivation quintile, comorbidities, and joint-specific function measured using the Oxford Hip Score (OHS) or Oxford Knee Score (OKS). Multivariate logistic regression was performed. EQ-5D and OHS/
Aims. To assess how the cost-effectiveness of total hip arthroplasty (THA) and total knee arthroplasty (TKA) varies with age, sex, and preoperative Oxford Hip or Knee Score (OHS/OKS); and to identify the patient groups for whom THA/TKA is cost-effective. Methods. We conducted a cost-effectiveness analysis using a Markov model from a United Kingdom NHS perspective, informed by published analyses of patient-level data. We assessed the cost-effectiveness of THA and TKA in adults with hip or knee osteoarthritis compared with having no arthroplasty surgery during the ten-year time horizon. Results. THA and TKA cost < £7,000 per quality-adjusted life-year (QALY) gained at all preoperative scores below the absolute referral thresholds calculated previously (40 for OHS and 41 for OKS). Furthermore, THA cost < £20,000/QALY for patients with OHS of ≤ 45, while TKA was cost-effective for patients with
Aims. To calculate how the likelihood of obtaining measurable benefit from hip or knee arthroplasty varies with preoperative patient-reported scores. Methods. Existing UK data from 222,933 knee and 209,760 hip arthroplasty patients were used to model an individual’s probability of gaining meaningful improvement after surgery based on their preoperative Oxford Knee or Hip Score (OKS/OHS). A clinically meaningful improvement after arthroplasty was defined as ≥ 8 point improvement in OHS, and ≥ 7 in
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. Methods. A mid-term follow-up of the remaining 125 patients from a randomized cohort of total knee arthroplasty patients (initially comprising 212 recruited patients), comparing modern (Triathlon) and traditional (Kinemax) prostheses was undertaken. Functional outcomes were assessed with the Oxford Knee Score (OKS), knee range of movement, pain numerical rating scales, lower limb power output, timed functional assessment battery, and satisfaction survey. Data were linked to earlier assessment timepoints, and analyzed by repeated measures analysis of variance (ANOVA) mixed models, incorporating longitudinal change over all assessment timepoints. Results. The mean follow-up of the 125 patients was 8.12 years (7.3 to 9.4). There was a reduction in all assessment parameters relative to earlier assessments. Longitudinal models highlight changes over time in all parameters and demonstrate large effect sizes. Significant between-group differences were seen in measures of knee flexion (medium-effect size), lower limb power output (large-effect size), and report of worst daily pain experienced (large-effect size) favouring the Triathlon group. No longitudinal between-group differences were observed in mean
Aims. To compare the gait of unicompartmental knee arthroplasty (UKA)
and total knee arthroplasty (TKA) patients with healthy controls,
using a machine-learning approach. Patients and Methods. 145 participants (121 healthy controls, 12 patients with cruciate-retaining
TKA, and 12 with mobile-bearing medial UKA) were recruited. The
TKA and UKA patients were a minimum of 12 months post-operative,
and matched for pattern and severity of arthrosis, age, and body
mass index. . Participants walked on an instrumented treadmill until their
maximum walking speed was reached. Temporospatial gait parameters,
and vertical ground reaction force data, were captured at each speed.
Oxford knee scores (OKS) were also collected. An ensemble of trees
algorithm was used to analyse the data: 27 gait variables were used
to train classification trees for each speed, with a binary output
prediction of whether these variables were derived from a UKA or
TKA patient. Healthy control gait data was then tested by the decision
trees at each speed and a final classification (UKA or TKA) reached
for each subject in a majority voting manner over all gait cycles
and speeds. Top walking speed was also recorded. Results. 92% of the healthy controls were classified by the decision tree
as a UKA, 5% as a TKA, and 3% were unclassified. There was no significant
difference in
This study compared patient-reported outcomes of three total knee arthroplasty (TKA) designs from one manufacturer: one cruciate-retaining (CR) design, and two cruciate-sacrificing designs, anterior-stabilized (AS) and posterior-stabilized (PS). Patients scheduled for primary TKA were included in a single-centre, prospective, three-armed, blinded randomized trial (n = 216; 72 per group). After intraoperative confirmation of posterior cruciate ligament (PCL) integrity, patients were randomly allocated to receive a CR, AS, or PS design from the same TKA system. Insertion of an AS or PS design required PCL resection. The primary outcome was the mean score of all five subscales of the Knee injury and Osteoarthritis Outcome Score (KOOS) at two-year follow-up. Secondary outcomes included all KOOS subscales, Oxford Knee Score, EuroQol five-dimension health questionnaire, EuroQol visual analogue scale, range of motion (ROM), and willingness to undergo the operation again. Patient satisfaction was also assessed.Aims
Methods
Aims. Medial unicompartmental knee arthroplasty (UKA) is associated
with successful outcomes in carefully selected patient cohorts.
We hypothesised that severity and location of patellofemoral cartilage
lesions significantly influences functional outcome after Oxford
medial compartmental knee arthroplasty. Patients and Methods. We reviewed 100 consecutive UKAs at minimum eight-year follow-up
(96 to 132). A single surgeon performed all procedures. Patients
were selected based on clinical and plain radiographic assessment.
All patients had end-stage medial compartment osteoarthritis (OA)
with sparing of the lateral compartment and intact anterior cruciate ligaments.
None of the patients had end-stage patellofemoral OA, but patients
with anterior knee pain or partial thickness chondral loss were
not excluded. There were 57 male and 43 female patients. The mean
age at surgery was 69 years (41 to 82). At surgery the joint was
carefully inspected for patellofemoral chondral loss and this was documented
based on severity of cartilage loss (0 to 4 Outerbridge grading)
and topographic location (medial, lateral, central, and superior
or inferior). Functional scores collected included Oxford Knee Score
(OKS), patient satisfaction scale and University College Hospital
(UCH) knee score. Intraclass correlation was used to compare chondral
damage to outcomes. Results. All patients documented significant improvement in pain and improved
functional scores at mid-term follow-up. There were four revisions
(mean 2.9 years, 2 to 4; standard deviation (. sd). 0.9) in
this cohort, three for tibial loosening and one for femoral loosening.
There was one infection that was treated with debridement and insert exchange.
The mean
The aim of this study was to describe the prevalence and patterns of neuropathic pain over one year in a cohort of patients with chronic post-surgical pain at three months following total knee arthroplasty (TKA). Between 2016 and 2019, 363 patients with troublesome pain, defined as a score of ≤ 14 on the Oxford Knee Score pain subscale, three months after TKA from eight UK NHS hospitals, were recruited into the Support and Treatment After Replacement (STAR) clinical trial. Self-reported neuropathic pain and postoperative pain was assessed at three, nine, and 15 months after surgery using the painDETECT and Douleur Neuropathique 4 (DN4) questionnaires collected by postal survey.Aims
Methods
The aim of this study was to compare a bicruciate-retaining (BCR) total knee arthroplasty (TKA) with a posterior cruciate-retaining (CR) TKA design in terms of kinematics, measured using fluoroscopy and stability as micromotion using radiostereometric analysis (RSA). A total of 40 patients with end-stage osteoarthritis were included in this randomized controlled trial. All patients performed a step-up and lunge task in front of a monoplane fluoroscope one year postoperatively. Femorotibial contact point (CP) locations were determined at every flexion angle and compared between the groups. RSA images were taken at baseline, six weeks, three, six, 12, and 24 months postoperatively. Clinical and functional outcomes were compared postoperatively for two years.Aims
Methods
The aim of this study was to compare the clinical outcomes of robotic arm-assisted bi-unicompartmental knee arthroplasty (bi-UKA) with conventional mechanically aligned total knee arthroplasty (TKA) during the first six weeks and at one year postoperatively. A per protocol analysis of 76 patients, 43 of whom underwent TKA and 34 of whom underwent bi-UKA, was performed from a prospective, single-centre, randomized controlled trial. Diaries kept by the patients recorded pain, function, and the use of analgesics daily throughout the first week and weekly between the second and sixth weeks. Patient-reported outcome measures (PROMs) were compared preoperatively, and at three months and one year postoperatively. Data were also compared longitudinally and a subgroup analysis was conducted, stratified by preoperative PROM status.Aims
Methods
Unicompartmental knee arthroplasty (UKA) is a bone-preserving treatment option for osteoarthritis localized to a single compartment in the knee. The success of the procedure is sensitive to patient selection and alignment errors. Robotic arm-assisted UKA provides technological assistance to intraoperative bony resection accuracy, which is thought to improve ligament balancing. This paper presents the five-year outcomes of a comparison between manual and robotically assisted UKAs. The trial design was a prospective, randomized, parallel, single-centre study comparing surgical alignment in patients undergoing UKA for the treatment of medial compartment osteoarthritis (ISRCTN77119437). Participants underwent surgery using either robotic arm-assisted surgery or conventional manual instrumentation. The primary outcome measure (surgical accuracy) has previously been reported, and, along with secondary outcomes, were collected at one-, two-, and five-year timepoints. Analysis of five-year results and longitudinal analysis for all timepoints was performed to compare the two groups.Aims
Methods
The primary objective of this study was to compare migration of the cemented ATTUNE fixed bearing cruciate retaining tibial component with the cemented Press-Fit Condylar (PFC)-sigma fixed bearing cruciate retaining tibial component. The secondary objectives included comparing clinical and radiological outcomes and Patient Reported Outcome Measures (PROMs). A single blinded randomized, non-inferiority study was conducted including 74 patients. Radiostereometry examinations were made after weight bearing, but before hospital discharge, and at three, six, 12, and 24 months postoperatively. PROMS were collected preoperatively and at three, six, 12, and 24 months postoperatively. Radiographs for measuring radiolucencies were collected at two weeks and two years postoperatively.Aims
Methods
The aim of this study was to compare the effectiveness of a femoral
nerve block and a periarticular infiltration in the management of
early post-operative pain after total knee arthroplasty (TKA). A pragmatic, single centre, two arm parallel group, patient blinded,
randomised controlled trial was undertaken. All patients due for
TKA were eligible. Exclusion criteria included contraindications
to the medications involved in the study and patients with a neurological
abnormality of the lower limb. Patients received either a femoral
nerve block with 75 mg of 0.25% levobupivacaine hydrochloride around
the nerve, or periarticular infiltration with 150 mg of 0.25% levobupivacaine
hydrochloride, 10 mg morphine sulphate, 30 mg ketorolac trometamol
and 0.25 mg of adrenaline all diluted with 0.9% saline to make a
volume of 150 ml.Aims
Patients and Methods
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. All patients undergoing surgery between January and August 2014
were eligible for inclusion. Prospective data were collected from
205 patients undergoing total hip arthroplasty (THA) and 231 patients
undergoing total knee arthroplasty (TKA). Outcomes were assessed
with the FJS-12 and the Oxford Hip and Knee Scores (OHS, OKS) pre-operatively,
then at six and 12 months post-operatively. Internal consistency,
convergent validity, effect size, relative validity and ceiling
effects were determined.Aims
Patients and Methods
There is a large amount of evidence available
about the relative merits of unicompartmental and total knee arthroplasty
(UKA and TKA). Based on the same evidence, different people draw
different conclusions and as a result, there is great variability
in the usage of UKA. The revision rate of UKA is much higher than TKA and so some
surgeons conclude that UKA should not be performed. Other surgeons
believe that the main reason for the high revision rate is that
UKA is easy to revise and, therefore, the threshold for revision
is low. They also believe that UKA has many advantages over TKA
such as a faster recovery, lower morbidity and mortality and better
function. They therefore conclude that UKA should be undertaken
whenever appropriate. The solution to this argument is to minimise the revision rate
of UKA, thereby addressing the main disadvantage of UKA. The evidence
suggests that this will be achieved if surgeons use UKA for at least
20% of their knee arthroplasties and use implants that are appropriate
for these broad indications. Cite this article:
Partial knee arthroplasty (PKA), either medial
or lateral unicompartmental knee artroplasty (UKA) or patellofemoral arthroplasty
(PFA) are a good option in suitable patients and have the advantages
of reduced operative trauma, preservation of both cruciate ligaments
and bone stock, and restoration of normal kinematics within the
knee joint. However, questions remain concerning long-term survival.
The goal of this review article was to present the long-term results
of medial and lateral UKA, PFA and combined compartmental arthroplasty
for multicompartmental disease. Medium- and long-term studies suggest
reasonable outcomes at ten years with survival greater than 95% in
UKA performed for medial osteoarthritis or osteonecrosis, and similarly
for lateral Cite this article:
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:
The cementless Oxford unicompartmental knee replacement
has been demonstrated to have superior fixation on radiographs and
a similar early complication rate compared with the cemented version.
However, a small number of cases have come to our attention where,
after an apparently successful procedure, the tibial component subsides into
a valgus position with an increased posterior slope, before becoming
well-fixed. We present the clinical and radiological findings of
these six patients and describe their natural history and the likely
causes. Two underwent revision in the early post-operative period,
and in four the implant stabilised and became well-fixed radiologically with
a good functional outcome. This situation appears to be avoidable by minor modifications
to the operative technique, and it appears that it can be treated
conservatively in most patients. Cite this article: