Unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) have both been shown to be effective treatments for osteoarthritis (OA) of the knee. Many studies have compared the outcomes of the two treatments, but less so with the use of robotics, or individualized TKA alignment techniques. Functional alignment (FA) is a novel technique for performing a TKA and shares many principles with UKA. Our aim was to compare outcomes from a case-matched series of robotic-assisted UKAs and robotic-assisted TKAs performed using FA. From a prospectively collected database between April 2015 and December 2019, patients who underwent a robotic-assisted medial UKA (RA-UKA) were case-matched with patients who had undergone a FA robotic-assisted TKA (RA-TKA) during the same time period. Patients were matched for preoperative BMI, sex, age, and Forgotten Joint Score (FJS). A total of 101 matched pairs were eligible for final review. Postoperatively the groups were then compared for differences in patient-reported outcome measures (PROMs), range of motion (ROM), ability to ascend and descend stairs, and ability to kneel.Aims
Methods
To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration. We performed a systematic literature search in MEDLINE, Embase, and Web of Science. The search string included multiple synonyms of the following keywords: "revision TKA", "outcome" and "prognostic factor". We searched for studies assessing the association between at least one prognostic factor and at least one outcome measure after rTKA surgery. Data on sample size, study design, prognostic factors, outcomes, and the direction of the association was extracted and included in an evidence map.Aims
Methods
The primary objective of this study was to compare the five-year tibial component migration and wear between highly crosslinked polyethylene (HXLPE) inserts and conventional polyethylene (PE) inserts of the uncemented Triathlon fixed insert cruciate-retaining total knee arthroplasty (TKA). Secondary objectives included clinical outcomes and patient-reported outcome measures (PROMs). A double-blinded, randomized study was conducted including 96 TKAs. Tibial component migration and insert wear were measured with radiostereometric analysis (RSA) at three, six, 12, 24, and 60 months postoperatively. PROMS were collected preoperatively and at all follow-up timepoints.Aims
Methods
Aims. To identify the responsiveness, minimal clinically important difference (MCID), minimal clinical important change (MIC), and patient-acceptable symptom state (PASS) thresholds in the 36-item Short Form Health Survey questionnaire (SF-36) (v2) for each of the eight dimensions and the total score following total knee arthroplasty (TKA). Methods. There were 3,321 patients undergoing primary TKA with preoperative and one-year postoperative
Higher osteoblastic bone activity is expected in aseptic loosening and painful unicompartmental knee arthroplasty (UKA). However, insights into normal bone activity patterns after medial UKAs are lacking. The aim of this study was to identify the evolution in bone activity pattern in well-functioning medial mobile-bearing UKAs. In total, 34 patients (13 female, 21 male; mean age 62 years (41 to 79); BMI 29.7 kg/m2 (23.6 to 42.1)) with 38 medial Oxford partial UKAs (20 left, 18 right; 19 cementless, 14 cemented, and five hybrid) were prospectively followed with sequential 99mTc-hydroxymethane diphosphonate single photon emission CT (SPECT)/CT preoperatively, and at one and two years postoperatively. Changes in mean osteoblastic activity were investigated using a tracer localization scheme with volumes of interest (VOIs), reported by normalized mean tracer values. A SPECT/CT registration platform additionally explored cortical tracer evolution in zones of interest identified by previous experimental research.Aims
Methods
To determine the relationship between articular cartilage status and clinical outcomes after medial opening-wedge high tibial osteotomy (MOHTO) for medial compartmental knee osteoarthritis at intermediate follow-up. We reviewed 155 patients (155 knees) who underwent MOHTO from January 2008 to December 2016 followed by second-look arthroscopy with a mean 5.3-year follow-up (2.0 to 11.7). Arthroscopic findings were assessed according to the International Cartilage Repair Society (ICRS) Cartilage Repair Assessment (CRA) grading system. Patients were divided into two groups based on the presence of normal or nearly normal quality cartilage in the medial femoral condyle: good (second-look arthroscopic) status (ICRS grade I or II; n = 70), and poor (second-look arthroscopic) status (ICRS grade III or IV; n = 85) groups at the time of second-look arthroscopy. Clinical outcomes were assessed using the International Knee Documentation Committee (IKDC) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and 36-Item Short Form survey.Aims
Methods
This study aimed to identify the tibial component and femoral component coronal angles (TCCAs and FCCAs), which concomitantly are associated with the best outcomes and survivorship in a cohort of fixed-bearing, cemented, medial unicompartmental knee arthroplasties (UKAs). We also investigated the potential two-way interactions between the TCCA and FCCA. Prospectively collected registry data involving 264 UKAs from a single institution were analyzed. The TCCAs and FCCAs were measured on postoperative radiographs and absolute angles were analyzed. Clinical assessment at six months, two years, and ten years was undertaken using the Knee Society Knee score (KSKS) and Knee Society Function score (KSFS), the Oxford Knee Score (OKS), the 36-Item Short-Form Health Survey questionnaire (SF-36), and range of motion (ROM). Fulfilment of expectations and satisfaction was also recorded. Implant survivorship was reviewed at a mean follow-up of 14 years (12 to 16). Multivariate regression models included covariates, TCCA, FCCA, and two-way interactions between them. Partial residual graphs were generated to identify angles associated with the best outcomes. Kaplan-Meier analysis was used to compare implant survivorship between groups.Aims
Methods
For many designs of total knee arthroplasty (TKA) it remains unclear whether cemented or uncemented fixation provides optimal long-term survival. The main limitation in most studies is a retrospective or non-comparative study design. The same is true for comparative trials looking only at the survival rate as extensive sample sizes are needed to detect true differences in fixation and durability. Studies using radiostereometric analysis (RSA) techniques have shown to be highly predictive in detecting late occurring aseptic loosening at an early stage. To investigate the difference in predicted long-term survival between cemented, uncemented, and hybrid fixation of TKA, we performed a randomized controlled trial using RSA. A total of 105 patients were randomized into three groups (cemented, uncemented, and hybrid fixation of the ACS Mobile Bearing (ACS MB) knee system, implantcast). RSA examinations were performed on the first day after surgery and at scheduled follow-up visits at three months, six months, one year, and two years postoperatively. Patient-reported outcome measures (PROMs) were obtained preoperatively and after two years follow-up. Patients and follow-up investigators were blinded for the result of randomization.Aims
Methods
Aims. While patients with psychological distress have poorer short-term outcomes after total knee arthroplasty (TKA), their longer-term function is unknown. We aimed to 1) assess the influence of preoperative mental health status on long-term functional outcomes, quality of life, and patient satisfaction; and 2) analyze the change in mental health after TKA, in a cohort of patients with no history of mental health disorder, with a minimum of ten years’ follow-up. Methods. Prospectively collected data of 122 patients undergoing primary unilateral TKA in 2006 were reviewed. Patients were assessed pre- and postoperatively at two and ten years using the Knee Society Knee Score (KSKS) and Function Score (KSFS); Oxford Knee Score (OKS); and the Mental (MCS) and Physical Component Summary (PCS) which were derived from the 36-Item Short-Form Health Survey questionnaire (SF-36). Patients were stratified into those with psychological distress (MCS < 50, n = 51) and those without (MCS ≥ 50, n = 71). Multiple regression was used to control for age, sex, BMI, Charlson Comorbidity Index (CCI), and baseline scores. The rate of expectation fulfilment and satisfaction was compared between patients with low and high MCS. Results. There was no difference in the mean KSKS, KSFS, OKS, and
The aim is to assess the cost-effectiveness of patellofemoral arthroplasty (PFA) in comparison with total knee arthroplasty (TKA) for the treatment of isolated patellofemoral osteoarthritis (OA) based on prospectively collected data on health outcomes and resource use from a blinded, randomized, clinical trial. A total of 100 patients with isolated patellofemoral osteoarthritis were randomized to receive either PFA or TKA by experienced knee surgeons trained in using both implants. Patients completed patient-reported outcomes including EuroQol five-dimension questionnaire (EQ-5D) and 6-Item Short-Form Health Survey questionnaire (SF-6D) before the procedure. The scores were completed again after six weeks, three, six, and nine months, and again after one- and two-year post-surgery and yearly henceforth. Time-weighted outcome measures were constructed. Cost data were obtained from clinical registrations and patient-reported questionnaires. Incremental gain in health outcomes (quality-adjusted life-years (QALYs)) and incremental costs were compared for the two groups of patients. Net monetary benefit was calculated assuming a threshold value of €10,000, €35,000, and €50,000 per QALY and used to test the statistical uncertainty and central assumptions about outcomes and costs.Aims
Methods
The aim of this independent multicentre study was to assess the
mid-term results of mobile bearing unicondylar knee arthroplasty
(UKA) for isolated lateral osteoarthritis of the knee joint. We retrospectively evaluated 363 consecutive, lateral UKAs (346
patients) performed using the Oxford domed lateral prosthesis undertaken
in three high-volume knee arthroplasty centres between 2006 and
2014. Mean age of the patients at surgery was 65 years (36 to 88)
with a mean final follow-up of 37 months (12 to 93)Aims
Patients and Methods
Little is known about the relative outcomes of revision of unicompartmental
knee arthroplasty (UKA) and high tibial osteotomy (HTO) to total
knee arthroplasty (TKA). The aim of this study is to compare the
outcomes of revision surgery for the two procedures in terms of
complications, re-revision and patient-reported outcome measures (PROMs)
at a minimum of two years follow-up. This study was a retrospective review of data from an institutional
arthroplasty registry for cases performed between 2001 and 2014.
A total of 292 patients were identified, of which 217 had a revision
of HTO to TKA, and 75 had revision of UKA to TKA. While mean follow-up
was longer for the HTO group compared with the UKA group, patient
demographics (age, body mass index and Charlson co-morbidity index)
and PROMs (Short Form-36, Oxford Knee Score, Knee Society Score,
both objective and functional) were similar in the two groups prior
to revision surgery. Outcomes included the rate of complications
and
re-operation, PROMS and patient-reported satisfaction at six months
and two years post-operatively. We also compared the duration of
surgery and the need for revision implants in the two groups. Aims
Patients and Methods
Advances in polyethylene (PE) in total hip arthroplasty
have led to interest and increased use of highly crosslinked PE
(HXLPE) in total knee arthroplasty (TKA). Biomechanical data suggest
improved wear characteristics for HXLPE inserts over conventional
PE in TKA. Short-term results from registry data and few clinical
trials are promising. Our aim is to present a review of the history
of HXLPEs, the use of HXLPE inserts in TKA, concerns regarding potential mechanical
complications, and a thorough review of the available biomechanical
and clinical data. Cite this article:
Knee joint distraction (KJD) is a relatively new, knee-joint
preserving procedure with the goal of delaying total knee arthroplasty
(TKA) in young and middle-aged patients. We present a randomised
controlled trial comparing the two. The 60 patients ≤ 65 years with end-stage knee osteoarthritis
were randomised to either KJD (n = 20) or TKA (n = 40). Outcomes
were assessed at baseline, three, six, nine, and 12 months. In the
KJD group, the joint space width (JSW) was radiologically assessed,
representing a surrogate marker of cartilage thickness.Aims
Patients and Methods
Our aim was to compare kinematic with mechanical alignment in
total knee arthroplasty (TKA). We performed a prospective blinded randomised controlled trial
to compare the functional outcome of patients undergoing TKA in
mechanical alignment (MA) with those in kinematic alignment (KA).
A total of 71 patients undergoing TKA were randomised to either
kinematic (n = 36) or mechanical alignment (n = 35). Pre- and post-operative
hip-knee-ankle radiographs were analysed. The knee injury and osteoarthritis
outcome score (KOOS), American Knee Society Score, Short Form-36,
Euro-Qol (EQ-5D), range of movement (ROM), two minute walk, and timed
up and go tests were assessed pre-operatively and at six weeks,
three and six months and one year post-operatively.Aims
Patients and Methods
Patients with osteoarthritis of the knee commonly have degenerative
meniscal tears. Arthroscopic meniscectomy is frequently performed,
although the benefits are debatable. Recent studies have concluded
that there is no role for arthroscopic washout in osteoarthritis
of the knee. Our aim was to perform a systematic review to assess
the evidence for the efficacy of arthroscopic meniscectomy in patients
with meniscal tears and degenerative changes in the knee. A literature search was performed, using the PubMed/MEDLINE database,
for relevant articles published between 1975 and 2015. A total of
six studies, including five randomised controlled trials and one
cross-sectional study of a prospective cohort, met the inclusion
criteria. Relevant information including study design, operations,
the characteristics of the patients, outcomes, adverse events and
further operations were extracted.Aims
Patients and Methods
A lack of connection between surgeons and patients in evaluating
the outcome of total knee arthroplasty (TKA) has led to the search
for the ideal patient-reported outcome measure (PROM) to evaluate
these procedures. We hypothesised that the desired psychometric properties
of the ideal outcome tool have not been uniformly addressed in studies describing
TKA PROMS. A systematic review was conducted investigating one or more facets
of patient-reported scores for measuring primary TKA outcome. Studies
were analysed by study design, subject demographics, surgical technique,
and follow-up adequacy, with the ‘gold standard’ of psychometric
properties being systematic development, validity, reliability,
and responsiveness.Objectives
Methods
Knee arthrodesis is a potential salvage procedure
for limb preservation after failure of total knee arthroplasty (TKA) due
to infection. In this study, we evaluated the outcome of single-stage
knee arthrodesis using an intramedullary cemented coupled nail without
bone-on-bone fusion after failed and infected TKA with extensor
mechanism deficiency. Between 2002 and 2012, 27 patients (ten female,
17 male; mean age 68.8 years; 52 to 87) were treated with septic
single-stage exchange. Mean follow-up duration was 67.1months (24
to 143, n = 27) (minimum follow-up 24 months) and for patients with
a minimum follow-up of five years 104.9 (65 to 143,; n = 13). A
subjective patient evaluation (Short Form (SF)-36) was obtained,
in addition to the Visual Analogue Scale (VAS). The mean VAS score was
1.44 (SD 1.48). At final follow-up, four patients had recurrent
infections after arthrodesis (14.8%). Of these, three patients were
treated with a one-stage arthrodesis nail exchange; one of the three
patients had an aseptic loosening with a third single-stage exchange,
and one patient underwent knee amputation for uncontrolled sepsis at
108 months. All patients, including the amputee, indicated that
they would choose arthrodesis again. Data indicate that a single-stage
knee arthrodesis offers an acceptable salvage procedure after failed
and infected TKA. Cite this article:
The routine use of patient reported outcome measures
(PROMs) in evaluating the outcome after arthroplasty by healthcare
organisations reflects a growing recognition of the importance of
patients’ perspectives in improving treatment. Although widely embraced
in the NHS, there are concerns that PROMs are being used beyond
their means due to a poor understanding of their limitations. This paper reviews some of the current challenges in using PROMs
to evaluate total knee arthroplasty. It highlights alternative methods
that have been used to improve the assessment of outcome. Cite this article:
Accurate, reproducible outcome measures are essential
for the evaluation of any orthopaedic procedure, in both clinical
practice and research. Commonly used patient-reported outcome measures (PROMs) have
drawbacks such as ‘floor’ and ‘ceiling’ effects, limitations of
worldwide adaptability and an inability to distinguish pain from
function. They are also unable to measure the true outcome of an
intervention rather than a patient’s perception of that outcome. Performance-based functional outcome tools may address these
problems. It is important that both clinicians and researchers are
aware of these measures when dealing with high-demand patients,
using a new intervention or implant, or testing a new rehabilitation
protocol. This article provides an overview of some of the clinically-validated
performance-based functional outcome tools used in the assessment
of patients undergoing hip and knee surgery. Cite this article:
