Comparative outcomes of total hip and knee arthroplasty: a prospective cohort study

Risk factors of chronic postoperative pain after total knee arthroplasty: a systematic review

BACKGROUND

There is a lack of relevant studies to grade the evidence on the risk factors of chronic pain after total knee arthroplasty (TKA), and only quantitative methods are used for systematic evaluation. The review aimed to systematically identify risk factors of chronic postoperative pain following TKA and to evaluate the strength of the evidence underlying these correlations.

METHODS

PubMed, Web of Science, Cochrane Library, Embase, and CINAHL databases were searched from initiation to September 2023. Cohort studies, case-control studies, and cross-sectional studies involving patients undergoing total knee replacement were included. A semi-quantitative approach was used to grade the strength of the evidence-based on the number of investigations, the quality of the studies, and the consistency of the associations reported by the studies.

RESULTS

Thirty-two articles involving 18,792 patients were included in the final systematic review. Ten variables were found to be strongly associated with postoperative pain, including Age, body mass index (BMI), comorbidities condition, preoperative pain, chronic widespread pain, preoperative adverse health beliefs, preoperative sleep disorders, central sensitization, preoperative anxiety, and preoperative function. Sixteen factors were identified as inconclusive evidence.

CONCLUSIONS

This systematic review clarifies which risk factors could be involved in future research on TKA pain management for surgeons and patients. It highlights those factors that have been controversial or weakly correlated, emphasizing the need for further high-quality studies to validate them. Most crucially, it can furnish clinicians with vital information regarding high-risk patients and their clinical attributes, thereby aiding in the development of preventive strategies to mitigate postoperative pain following TKA.

TRIAL REGISTRATION

This systematic review has been registered on the PROSPERO platform (CRD42023444097).

Early perioperative quality of recovery after hip and knee arthroplasty: a retrospective comparative cohort study

PURPOSE

Increasing our knowledge about postoperative global Quality-Of-Recovery (QoR) after THA and TKA is important to improve perioperative medicine, in particular for preoperative patient information and benchmarking of postoperative patient status.

METHODS

This study is a single centre, retrospective cohort study of prospectively collected data, conducted in Strasbourg University Hospital, Strasbourg, France. The main outcome was the modified French version of the QoR-15 (mQoR-15F) score monitored preoperatively, at postoperative day one, three, 14 and 28. We questioned the hypothesis: would THA and TKA recovery patterns differ and would postoperative health status eventually overreach the preoperative reference?

RESULTS

The mQoR-15F was statistically higher in the THA group compared to the TKA group in POD 1 and 28 (112 ± 17 vs. 107 ± 17; p < 0.01 and 131 ± 12 vs. 127 ± 15; p = 0.02, respectively). The mean postoperative time delay to reach preoperative mQoR-15F was seven and 16 days for THA and TKA patients, respectively.

CONCLUSION

Early postoperative health status after THA and TKA differs significantly; TKA being associated with a larger early decrease of global health status compared to THA. Both THA and TKA groups global health status overreached preoperative levels after one and two weeks postoperatively. These surgery-specific recovery profiles may favor improved patient information to steer advised operative decision and set specific recovery goals as part of enhanced recovery pathways.

Can Arthroplasty Stem Influence Outcome: A Randomized Controlled Trial of Stem Length in Cemented Total Hip Arthroplasty

BACKGROUND

The primary aim was to assess whether a short (125 millimeter (mm)) stem offered an equivalent hip-specific function compared to the standard (150 mm) stem when used for cemented total hip arthroplasty. Secondary aims were to evaluate health-related quality of life, patient satisfaction, stem height and alignment, as well as radiographic loosenings and complications between the two stems.

METHODS

A prospective twin-center double-blind randomized control trial was conducted. During a 15-month period, 220 patients undergoing total hip arthroplasty were randomized to either a standard (n = 110) or a short (n = 110) stem. There were no significant (P ≥ .065) differences in preoperative variables between the groups. Functional outcomes and radiographic assessment were undertaken at a mean of 1 and 2 years.

RESULTS

There were no differences (P = .428) in hip-specific function according to the mean Oxford hip scores at 1 year (primary endpoint) or at 2 years (P = .622) between the groups. The short stem group had greater varus angulation (0.9 degrees, P = .003) when compared to the standard group and were more likely (odds ratio 2.42, P = .002) to have varus stem alignment beyond one standard deviation from the mean. There were no significant (P ≥ .083) differences in the forgotten joint scores, EuroQol-5-Dimension, EuroQol-visual analogue scale, short form 12, patient satisfaction, complications, stem height, or radiolucent zones at 1 or 2 years between the groups.

CONCLUSION

The cemented short stem used in this study had equivalent hip-specific function, health-related quality of life, and patient satisfaction when compared to the standard stem at mean 2 years post operation. However, the short stem was associated with a greater rate of varus malalignment, which may influence future implant survival.

3D Bioprinting of Hyaline Articular Cartilage: Biopolymers, Hydrogels, and Bioinks

The musculoskeletal system, consisting of bones and cartilage of various types, muscles, ligaments, and tendons, is the basis of the human body. However, many pathological conditions caused by aging, lifestyle, disease, or trauma can damage its elements and lead to severe disfunction and significant worsening in the quality of life. Due to its structure and function, articular (hyaline) cartilage is the most susceptible to damage. Articular cartilage is a non-vascular tissue with constrained self-regeneration capabilities. Additionally, treatment methods, which have proven efficacy in stopping its degradation and promoting regeneration, still do not exist. Conservative treatment and physical therapy only relieve the symptoms associated with cartilage destruction, and traditional surgical interventions to repair defects or endoprosthetics are not without serious drawbacks. Thus, articular cartilage damage remains an urgent and actual problem requiring the development of new treatment approaches. The emergence of biofabrication technologies, including three-dimensional (3D) bioprinting, at the end of the 20th century, allowed reconstructive interventions to get a second wind. Three-dimensional bioprinting creates volume constraints that mimic the structure and function of natural tissue due to the combinations of biomaterials, living cells, and signal molecules to create. In our case-hyaline cartilage. Several approaches to articular cartilage biofabrication have been developed to date, including the promising technology of 3D bioprinting. This review represents the main achievements of such research direction and describes the technological processes and the necessary biomaterials, cell cultures, and signal molecules. Special attention is given to the basic materials for 3D bioprinting-hydrogels and bioinks, as well as the biopolymers underlying the indicated products.

Single-level Lumbar Fusion Versus Total Joint Arthroplasty: A Comparison of 1-year Outcomes

INTRODUCTION

Primary hip and knee arthroplasty represent two of the most successful orthopaedic surgical interventions in the past century. Similarly, lumbar fusion (LF) remains a valuable, evidence-based option to relieve pain and disability related to spinal degenerative conditions. This study evaluates the relative improvements in 1-year health-related quality of life (HRQOL) measures among patients undergoing primary single-level LF, primary total hip arthroplasty (THA), and primary total knee arthroplasty (TKA).

METHODS

Patients older than 18 years who underwent primary single-level posterior LF (posterolateral decompression and fusion with or without transforaminal lumbar interbody fusion, involving any single lumbar level), TKA, and THA at a single academic institution were retrospectively identified. Patient demographics and surgical characteristics were collected. HRQOL measures were collected preoperatively and at 1-year postoperative time point including Short-Form 12 Physical Component Score (PCS) and Mental Component Score (MCS) along with subspecialty-specific outcomes.

RESULTS

A total of 2,563 patients were included (346 LF, 1,035 TKA, and 1,182 THA). Change in MCS-12 and PCS-12 after LF did not vary markedly by preoperative diagnosis. LF patients had a significantly lower preoperative MCS-12 (LF: 50.8, TKA: 53.9, THA: 52.9, P < 0.001), postoperative MCS-12 (LF: 52.5, TKA: 54.8, THA: 54.5, P < 0.001), postoperative PCS-12 (LF: 40.1, TKA: 44.0, THA: 43.9, P < 0.001), ΔPCS-12 (LF: 7.9, TKA: 10.8, THA: 11.9, P < 0.001), and PCS-12 recovery ratio (LF: 10.7%, TKA: 15.1%, THA 16.6%, P < 0.001) compared with TKA and THA patients. In regression analysis, both TKA and LF were found to be independently associated with a smaller ΔPCS-12 improvement (TKA: β = -1.36, P = 0.009; LF: β = -4.74, P < 0.001) compared with THA. TKA (β = -1.42, P = 0.003) was also independently associated with a smaller ΔMCS-12 improvement compared with THA.

CONCLUSIONS

Patients undergoing single-level LF, TKA, and THA demonstrate notable improvements in HRQOL outcomes at 1 year postoperatively compared with preoperative baseline scores. The greatest improvements were found among THA patients, followed subsequently by TKA and LF patients. Both LF and TKA were independently associated with markedly less improvement in physical disability at 1 year postoperatively compared with THA.

STUDY DESIGN

Retrospective Cohort Study.

Functional Outcomes Following Hip Replacement in Community-Dwelling Older Adults

Uncertainty remains regarding the benefit of hip replacement in older adults in the context of age-related decline in physical function. This study aimed to examine the effect of hip replacement on functional outcomes and identify factors associated with clinically important improvement in physical function postoperatively in community-dwelling older adults. This cohort study was performed within the ASPREE trial, with 698 participants receiving hip replacement and 677 age- and sex-matched controls without knee or hip replacement during the trial drawn from 16,703 Australian participants aged ≥70 years. Health status (physical and mental component summary [PCS and MCS]) was assessed annually using the SF-12. Participants receiving hip replacement had significantly lower pre- and post-replacement PCS scores compared with controls (p < 0.0001). There was significant improvement in PCS score following hip replacement (mean change 4.9, 95%CI 4.0−5.7) but no change in controls (0.01, 95%CI −0.7−0.7). Following hip replacement, 46.7% of participants experienced clinically important improvement in PCS score, while 15.5% experienced worsened PCS score. Participants experiencing improved postoperative PCS score had significantly lower PCS and higher MCS scores preoperatively. The degree of preoperative physical function impairment was a significant indicator of older people most likely to benefit from hip replacement surgery.

Hospital Consumer Assessment of Healthcare Providers and Systems survey response rates are significantly affected by patient characteristics and postoperative outcomes for patients undergoing primary total knee arthroplasty

INTRODUCTION

The Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey measures patients' satisfaction of their hospital experience. A minority of discharged patients return the survey. Underlying bias among who ultimately returns the survey (non-response bias) after total knee arthroplasty (TKA) may affect results of the survey. Thus, the objective of the current study is to assess the relationship between patient characteristics and postoperative outcomes on HCAHPS survey nonresponse.

METHODS

All adult patients at a single institution undergoing inpatient, elective, primary TKA between February 2013 and May 2020 were selected for analysis. Following discharge, all patients had been mailed the HCAHPS survey. The primary outcome analyzed in the current study is survey return. Patient characteristics, surgical variables, and 30-day postoperative outcomes were analyzed. Univariate and multivariate analyses were performed to identify factors independently associated with return of the HCAHPS survey.

RESULTS

Of 4,804 TKA patients identified, 1,498 (31.22%) returned HCAHPS surveys. On multivariate regression analyses controlling for patient factors, patients who did not return the survey were more likely to have a higher American Society of Anesthesia score (ASA score of 4 or higher, OR = 2.37; P<0.001), and be partially or totally dependent (OR = 2.37; P = 0.037). Similarly, patients who did not return the survey were more likely to have had a readmission (OR = 1.94; P<0.001), be discharged to a place other than home (OR = 1.52; P<0.001), or stay in the hospital for longer than 3 days (OR = 1.43; P = 0.004).

DISCUSSION

Following TKA, HCAHPS survey response rate was only 31.22% and completion of the survey was associated with several demographic and postoperative variables. These findings suggest that HCAHPS survey results capture a non-representative fraction of the true TKA patient population. This bias is necessary to consider when using HCAHPS survey results as a metric for quality of healthcare and federal reimbursement rates.

Hip and Knee Replacement Patients' Experiences With an Orthopaedic Patient Navigator: A Qualitative Study

Hip and knee replacement surgery is common, yet more than 10% of patients who undergo total hip replacement (THR) and total knee replacement (TKR) report postsurgery dissatisfaction. Recommendations for improving patient experience after total joint replacement surgery include increasing support to patients, including having a patient navigator available to patients before and after surgery. This article reports on THR and TKR patients' experiences of using an orthopaedic patient navigator. We employed qualitative description to understand THR and TKR patients' experiences of interacting with an orthopaedic patient navigator in a community teaching hospital. Telephone interviews were conducted with 15 purposefully selected total joint replacement patients (TKR: n = 11; THR: n = 4) who had at least one contact with the navigator. Interview transcripts were analyzed using thematic analysis. Patients described receiving physical support services, emotional support services, informational support services, and care coordination services from the patient navigator. All interactions with the patient navigator were positive. Knowing the patient navigator was available for any future concerns also provided indirect benefits of reassurance, comfort, and security. Patients described these direct and indirect benefits as potentially having long-lasting and resilient positive effects. An orthopaedic patient navigator can have a positive impact on patients' THR and TKR experience and fill gaps in support identified in earlier studies. Addressing patients' complex and varied care needs is well suited to a clinical nurse specialist in the role. Investing in an orthopaedic patient navigator provides reassurance to patients that their needs are a priority and will be addressed in a timely manner.

Higher body mass index is associated with larger postoperative improvement in patient-reported outcomes following total knee arthroplasty

BACKGROUND

Total knee arthroplasty is known to successfully alleviate pain and improve function in endstage knee osteoarthritis. However, there is some controversy with regard to the influence of obesity on clinical benefits after TKA. The aim of this study was to investigate the impact of body mass index (BMI) on improvement in pain, function and general health status following total knee arthroplasty (TKA).

METHODS

A single-centre retrospective analysis of primary TKAs performed between 2006 and 2016 was performed. Data were collected preoperatively and 12-month postoperatively using WOMAC score and EQ-5D. Longitudinal score change was compared across the BMI categories identified by the World Health Organization.

RESULTS

Data from 1565 patients [mean age 69.1, 62.2% women] were accessed. Weight distribution was: 21.2% BMI < 25.0 kg/m2, 36.9% BMI 25.0-29.9 kg/m2, 27.0% BMI 30.0-34.9 kg/m2, 10.2% BMI 35.0-39.9 kg/m2, and 4.6% BMI ≥ 40.0 kg/m2. All outcome measures improved between preoperative and 12-month follow-up (p < 0.001). In pairwise comparisons against normal weight patients, patients with class I-II obesity showed larger improvement on the WOMAC function and total score. For WOMAC pain improvements were larger for all three obesity classes.

CONCLUSIONS

Post-operative improvement in joint-specific outcomes was larger in obese patients compared to normal weight patients. These findings suggest that obese patients may have the greatest benefits from TKA with regard to function and pain relief one year post-op. Well balanced treatment decisions should fully account for both: Higher benefits in terms of pain relief and function as well as increased potential risks and complications. Trial registration This trial has been registered with the ethics committee of Eastern Switzerland (EKOS; Project-ID: EKOS 2020-00,879).

Oxford Knee Score and EQ-5d poorly predict patient's satisfaction following mechanically aligned total knee replacement: A cross-sectional study

BACKGROUND

Patient satisfaction is increasingly used to measure the success of arthroplasty. Satisfaction with the outcome of a total knee replacement (TKR) is traditionally thought to be associated with improvements in functional status and quality of life measures. This study aims to answer the following questions: 1. What is the level of patient satisfaction, improvement in knee function and patient quality of life associated with mechanically aligned TKR? 2. What is the relationship between OKS, EQ-5d scores and 'outcome satisfaction'?

HYPOTHESIS

TKR is associated with a significant improvement in function, satisfaction and quality of life and that there is a strong correlation between OKS, EQ-5d and 'outcome satisfaction'.

METHOD

Five thousand eight hundred and ninety six patients underwent primary TKR between January 2010 and December 2017 and had complete preoperative and 2-year follow-up data for OKS, EQ-5d and satisfaction scores. Outcomes data were collected prospectively and recorded on our institutional database. Minimal clinically important difference (MCID) and the Patient acceptable symptomatic state (PASS) were calculated for OKS and EQ-5d, the association between OKS, EQ-5d and 'outcome satisfaction' was measured using regression analysis.

RESULTS

The median 2-year 'outcome satisfaction' score was 90/100 with 79% of patients reporting excellent satisfaction (≥80/100) and 93.4% of patients satisfied (≥50/100). Postoperatively, median scores were 39 for OKS and 0.8 for EQ-5d. The mean increase in scores was 15.85 for OKS and 0.32 for EQ-5d. Satisfaction showed moderate positive correlation with postoperative OKS (r=0.69) and EQ-5D (0.58) scores, but weaker correlation with the change in OKS (r=0.57) and EQ-5d (r=0.32) scores from preoperative levels.

DISCUSSION/CONCLUSION

Mechanically aligned TKR is overall a successful operation responsible of fair rate of patient satisfaction. OKS and EQ-5d are imperfect predictors for satisfaction as they are significantly influenced by patients' comorbidities. This should be taken into account when evaluating the success of an operation.

LEVEL OF EVIDENCE

IIc; observational study (based on prospectively collected data from an institutional registry).

Direct superior approach for total hip arthroplasty

AIMS

The purpose of this study was to compare the clinical, radiological, and patient-reported outcome measures (PROMs) in the first 100 consecutive patients undergoing total hip arthroplasty (THA) via a direct superior approach (DSA) with a matched group of patients undergoing THA by the same surgeon, using a posterolateral approach (PLA).

METHODS

This was a retrospective single surgeon study comparing the first 100 consecutive DSA THA patients with a matched group of patients using a standard PLA. Case notes were examined for patient demographics, length of hospital stay, operating time, intra- and postoperative complications, pain score, satisfaction score, and Oxford Hip Score (OHS). Leg length discrepancy and component positioning were measured from postoperative plain radiographs.

RESULTS

The DSA patients had a shorter length of hospital stay (mean 2.09 days (SD 1.20) DSA vs 2.74 days (SD 1.17) PLA; p < 0.001) and shorter time to discharge from the inpatient physiotherapy teams (mean 1.44 days (SD 1.17) DSA vs 1.93 days (SD 0.96) PLA; p < 0.001). There were no differences in operating time (p = 0.505), pain levels up to postoperative day 1 (p = 0.106 to p =0.242), OHS (p = 0.594 to p = 0.815), satisfaction levels (p = 0.066 to p = 0.299), stem alignment (p = 0.240), acetabular component inclination (p < 0.001) and anteversion (p < 0.001), or leg length discrepancy (p = 0.134).

CONCLUSION

While the DSA appears safe and was not associated with a significant difference in PROMs, radiological findings, or intraoperative or postoperative complications, a randomized controlled trial with functional outcomes in the postoperative phase is needed to evaluate this surgical approach formally. Cite this article: Bone Joint J 2021;103-B(3):500-506.

Objective characterization of hip pain levels during walking by combining quantitative electroencephalography with machine learning

Pain is an undesirable sensory experience that can induce depression and limit individuals' activities of daily living, in turn negatively impacting the labor force. Affected people frequently feel pain during activity; however, pain is subjective and difficult to judge objectively, particularly during activity. Here, we developed a system to objectively judge pain levels in walking subjects by recording their quantitative electroencephalography (qEEG) and analyzing data by machine learning. To do so, we enrolled 23 patients who had undergone total hip replacement for pain, and recorded their qEEG during a five-minute walk via a wearable device with a single electrode placed over the Fp1 region, based on the 10-20 Electrode Placement System, before and three months after surgery. We also assessed subject hip pain using a numerical rating scale. Brain wave amplitude differed significantly among subjects with different levels of hip pain at frequencies ranging from 1 to 35 Hz. qEEG data were also analyzed by a support vector machine using the Radial Basis Functional Kernel, a function used in machine learning. That approach showed that an individual's hip pain during walking can be recognized and subdivided into pain quartiles with 79.6% recognition Accuracy. Overall, we have devised an objective and non-invasive tool to monitor an individual's pain during walking.

The Relationship Between Psychological Aspects and Trajectories of Symptoms in Total Knee Arthroplasty and Total Hip Arthroplasty

BACKGROUND

This study aimed to examine different trajectories of physical symptoms in hip and knee arthroplasty patients from presurgery to 1 year postsurgery and relate this to preoperative anxiety and depressive symptoms.

METHODS

Patients (N = 345) completed the Hip injury and Osteoarthritis Outcome Score or the Knee injury and Osteoarthritis Outcome Score to examine their preoperative and postoperative pain, stiffness, and function, presurgery, and 3, 6, and 12 months postsurgery. Presurgery anxiety and depressive symptoms were assessed using the 7-item Generalized Anxiety Disorder Scale and the 9-item Patient Health Questionnaire. Latent trajectory analysis was used to identify different subgroups in trajectories. The step-3 method was used to assess subgroup characteristics.

RESULTS

The effect of time on pain, function, and stiffness was different between subgroups of patients. Knee patients belonged mainly to classes with least improvement. Least improvement in pain was characterized by a combination of high levels of both anxiety and depressive symptoms. Anxiety and depressive symptoms were independently related to less reduction in stiffness while little improvement in function was characterized by higher depressive symptoms.

CONCLUSION

The results of this study indicate that anxiety and depressive symptoms were significantly, but differently, related to the distinct physical symptoms examined.

Preoperative vitamin D level does not affect the short-term functional outcome after total knee arthroplasty in elderly women

Background

We aimed to evaluate the effect of vitamin D levels on the functional outcome of elderly women who underwent total knee arthroplasty (TKA).

Methods

Seven hundred and four patients (1013 knees) who underwent primary TKA were included in our retrospective study. Preoperative vitamin D levels were measured and the relationship analyzed between these and age, weight, height, body mass index, and bone mineral density. Two hundred and twenty patients (220 knees) who received unilateral TKA and were followed up for more than 1 year after operation were divided into two groups: Group 1, serum 25-hydroxyvitamin D3 (25(OH)D3) level < 20 ng/ml; and Group 2, 25(OH)D3 level ≥ 20 ng/ml. Both groups were evaluated for the relationship between vitamin D levels and postoperative Visual Analogue Scale (VAS) score, Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score.

Results

The number of vitamin D-deficient patients (< 20 ng/ml of serum 25(OH)D3 level) was 556 (79.0%). In the correlation analysis, the vitamin D level was negatively correlated with weight only (p = 0.033). No significant differences were observed between the groups in terms of postoperative VAS score, KSKS, KSFS, and WOMAC score.

Conclusions

Vitamin D deficiency was highly prevalent in patients who underwent TKA. Vitamin D levels negatively correlated with weight. Low vitamin D level was not a risk factor for unsatisfactory TKA outcome in elderly women.

Do dissatisfied patients have unrealistic expectations? A systematic review and best-evidence synthesis in knee and hip arthroplasty patients

End-stage osteoarthritis is commonly treated with joint replacement. Despite high clinical success rates, up to 28% of patients are dissatisfied with the outcome.

This best-evidence synthesis aimed to review studies with different forms of study design and methodology that examined the relationship between (fulfilment of) outcome expectations of hip and knee patients and satisfaction with outcome.

A literature search was performed in PubMed, Web of Science, PsycInfo, Cochrane, and Google Scholar to identify studies conducted up to November 2017. The methodological quality of studies was assessed using the Newcastle-Ottawa Scale.

In this best-evidence synthesis systematic review, the following main results could be seen. In only half of all studies were preoperative expectations associated with level of satisfaction, while in almost all studies (93%), fulfilment of expectations was related to satisfaction. The effect of met expectations did not differ between hip and knee patients or study design.

Fulfilment of expectations seems to be consistently associated with patient satisfaction with outcome. Emphasis in future research must be placed on the operationalization and measurement of expectations and satisfaction to determine the (strength of the) influence of these different forms of assessment on the (existence of the) relationship.

Cite this article: EFORT Open Rev 2020;5:226-240. DOI: 10.1302/2058-5241.5.190015

Osteoarthritis Preoperative Package for care of Orthotics, Rehabilitation, Topical and oral agent Usage and Nutrition to Improve ouTcomes at a Year (OPPORTUNITY); a feasibility study protocol for a randomised controlled trial

Background

Patients’ pre-operative health and physical function is known to influence their post-operative outcomes. In patients with knee osteoarthritis, pharmacological and non-pharmacological options are often not optimised prior to joint replacement. This results in some patients undergoing surgery when they are not as fit as they could be. The aim of this study is to assess the feasibility and acceptability of a pre-operative package of non-operative care versus standard care prior to joint replacement.

Methods/design

This is a multicentre, randomised controlled feasibility trial of patients undergoing primary total knee replacement for osteoarthritis. Sixty patients will be recruited and randomised (2:1) to intervention or standard care arms. Data will be collected at baseline (before the start of the intervention), around the end of the intervention period and a minimum of 90 days after the planned date of surgery. Adherence will be reviewed each week during the intervention period (by telephone or in person). Participants will be randomised to a pre-operative package of non-operative care or standard care. The non-operative care will consist of (1) a weight-loss programme, (2) a set of exercises, (3) provision of advice on analgesia use and (4) provision of insoles. The intervention will be started as soon as possible after patients have been added to the waiting list for joint replacement surgery to take advantage of the incentive for behavioural change that this will create. The primary outcomes of this study are feasibility outcomes which will indicate whether the intervention and study protocol is feasible and acceptable and whether a full-scale effectiveness trial is warranted.

The following will be measured and used to inform study feasibility: rate of recruitment, rate of retention at 90-day follow-up review after planned surgery date, and adherence to the intervention estimated through review questionnaires and weight change (for those receiving the weight-loss aspect of intervention). In addition the following information will be assessed qualitatively: analysis of qualitative interviews exploring acceptability, feasibility, adherence and possible barriers to implementing the intervention, and acceptability of the different outcome measures.

Discussion

The aims of the study specifically relate to testing the feasibility and acceptability of the proposed effectiveness trial intervention and the feasibility of the trial methods.

This study forms the important first step in developing and assessing whether the intervention has the potential to be assessed in a future fully powered effectiveness trial. The findings will also be used to refine the design of the effectiveness trial.

Trial registration

ISRCTN registry, ID: ISRCTN96684272. Registered on 18 April 2018.

Serum Cartilage Oligomeric Matrix Protein in Late-Stage Osteoarthritis: Association with Clinical Features, Renal Function, and Cardiovascular Biomarkers

This study aimed to assess associations between serum cartilage oligomeric matrix protein (sCOMP) and phenotypic characteristics in late-stage hip and knee Osteoarthritis (OA) as well as its correlation with further serum markers of possible comorbidities in the Ulm Osteoarthritis Study. Moreover, the prognostic relevance of preoperative sCOMP concentrations for short-term functionality and pain outcomes after hip or knee joint replacement was explored. Preoperative serum samples and detailed information about the health status (i.e., WOMAC scores, Hannover Functionality Status (FFbH)) of 754 OA patients undergoing total joint replacement were included. Spearman rank-correlation coefficients and multiple linear regression models were used to evaluate the relationships between sCOMP, other serum markers, and health outcomes. There was a significant positive association between sCOMP and markers of renal (cystatin C, creatinine, and eGFR) and cardiac (e.g., NT-proBNP) impairment. Since renal failure might cause accumulation of sCOMP, additional adjustment with eGFR was performed. Preoperative sCOMP levels in knee OA but not hip OA patients were positively associated with FFbH, WOMAC function sub-scale and total WOMAC scale as well as the post-operative WOMAC stiffness sub-scale six months after surgery. Our data clearly demonstrate an association between sCOMP and renal function as well as other confounding factors, which should be considered in future biomarker studies.

Characterizing patients' expectations in hip and knee osteoarthritis

PURPOSE

Previous research reported conflicting findings regarding the association of sociodemographic and clinical variables with expectations for surgical outcomes. The current study aimed to identify and characterize different subgroups of osteoarthritis patients with respect to amount and level of expectations, and to examine factors that are associated with expectations.

METHODS

Hip and knee patients (n = 287) completed a questionnaire 1 week post consultation. Linear regression analyses were performed to examine whether sociodemographic (e.g., age, sex) and clinical factors (e.g., pain, function) were associated with expectations. Latent class analysis (LCA) was used to identify different subgroups and the step 3 method was conducted to assess subgroup characteristics.

RESULTS

Mean age of patients was 70 years (SD = 8) and 57% of patients was female. Most improvement was expected in walking ability and pain relief. Higher expectations were associated with younger age, male sex, and functional disability. Both hip and knee patients could be classified into three subgroups. These subgroups differed significantly on pain and other symptoms, and functional disability.

CONCLUSION

Both hip and knee patients reported pain and other osteoarthritis symptoms and functional disability and consequently had high expectations in these areas for treatment outcomes. Higher expectations were characterized by more pain, more symptoms and more functional disability. These insights could guide physicians in the discussion of expectations during consultation.

Trajectories of functional performance and muscle strength recovery differ after total knee and total hip replacement: a performance-based, longitudinal study

Total joint replacement is indicated to alleviate pain and disability associated with hip and knee osteoarthritis. Arthroplasty outcomes are typically reported together, or anecdotal comparisons are made between total knee arthroplasty (TKA) and total hip arthroplasty (THA) recovery. Limited data quantifies differences in recovery trajectories, especially with respect to performance-based outcomes. Seventy-nine people undergoing total knee or THA were followed over 6 months. Functional performance was measured using the stair climb test, timed-up-and-go test, and 6-min walk test. Surgical limb isometric strength was also measured. All outcomes significantly declined 1 month after surgery. Participants in the TKA group showed a greater decline in climbing stairs (P < 0.001), timed-up-and-go (P = 0.01), and 6-min walk distance (P < 0.01). Further, the TKA group lost more strength (P < 0.001) and were weaker than those after THA (P < 0.001). Differences in postoperative outcomes between groups at 3 and 6 months were also observed. The TKA group experiences a greater decline in measured outcomes than the THA group, and muscle strength and functional recovery occurred differently in each group. These findings should be considered in rehabilitation priorities after arthroplasty surgery.

Different targets of mechanical alignment do not improve knee outcomes after TKA

BACKGROUND

Accurate alignment is a basic principle of TKA surgery, but achieving alignment within this target may not translate into superior outcomes after surgery.

PURPOSE

To assess if neutral TKA mechanical alignment was associated with superior knee outcomes and to examine the effect of various aspects of pre-operative and post-operative alignment on knee function.

METHODS

Analysis of a database of 444 TKA patients between June 2009 and October 2016. Knee outcomes (WOMAC, AKSS and knee range of motion) were collected before surgery and during follow-up at a minimum of six months.

RESULTS

Analysis included 444 TKA patients (62% female, mean age 66 years, mean follow-up 23 months). Deformity varied from 21° varus (mean = 7.9, SD = 2.8) to 17° valgus deformity (mean = 7.7, SD = 2.8). Pre-operatively, 101 (23%) knees were in native neutral mechanical alignment, while 278 (63%) were in varus and 65 (15%) were in valgus. Post-operatively, a group of 365 (82%) TKA were found to be in neutral mechanical alignment and a group of 79 (18%) TKA were noted to be 'Outliers' (17 [4%] TKA > 3° varus and 62 [14%] TKA > 3° valgus alignment). Restoration of the target of alignment of 0 ± 3° or 0 ± 1°, did not have better functional outcomes scores, range of motion or prosthesis longevity than those in the outlier range.

CONCLUSION

Neutral TKA alignment did not appear to be a significant contributing factor to the improvement in knee function in short-medium term follow-up.

Fretting and Corrosion Damage of Retrieved Dual-Mobility Total Hip Arthroplasty Systems

BACKGROUND

Dual-mobility (DM) total hip arthroplasty (THA) systems are designed to increase stability while potentially avoiding problems associated with large femoral heads. Complications of these systems are not yet fully understood. This study aims at characterizing in vivo performance of DM hip systems and assessing modes of clinical failure.

METHODS

Under an institutional review board-approved implant retrieval protocol, 18 DM THA systems from 17 patients were included. Implants were graded at the head-neck junction for fretting and corrosion based on the system of Goldberg et al. Components were also macroscopically examined for different damage modes. Demographics and surgical data were collected from medical records, and radiographs were assessed for component positioning. Data were analyzed through Spearman rank-order correlation and Mann-Whitney U-tests, with α = 0.05.

RESULTS

The average length of implantation was 13.4 months with mild to moderate fretting corrosion damage. Polyethylene (PE) liners exhibited edge deformation, scratching, and pitting damage. Metallic components exhibited burnishing and scratching damage. Summed fretting and corrosion scores were strongly correlated (ρ = 0.967, P < .0001). Summed corrosion score was moderately correlated with presence of embedding on the PE liner (ρ = 0.690, P = .017). PE liner abrasion and edge deformation of the femoral stem taper were moderately positively correlated (ρ = 0.690, P = .017). Fretting and corrosion damage were not significantly correlated with patient demographics or radiographic positioning of implants. There were no differences in scores between modular and monoblock designs.

CONCLUSION

These findings demonstrate that dual-mobility THA systems may be susceptible to the same fretting and corrosion damage observed in traditional modular THA systems. Future studies are needed to confirm these results and clinical significance.

The Net Promoter Scores with Friends and Family Test after four hand surgery procedures

The Friends and Family Test, a variant of the Net Promoter Score, was adapted for the National Health Service to evaluate overall patient satisfaction and how likely patients are to recommend an intervention. It ranges from -100 to 100. Positive scores indicate good performance. This study quantifies the scores in 810 patients at a mean of 14 months following four common procedures. The score was 83 for trigger finger release ( n = 103), 68 for carpal tunnel decompression ( n = 467), 62 for surgery for Dupuytren's disease ( n = 224) and 44 for ganglia excision ( n = 16). Our study indicates that these procedures are highly valued and are recommended by patients according to the Friends and Family Test. The results of the Friends and Family Test correlated well with postoperative functional improvement and satisfaction. We conclude from this study that a compound score based on the Friends and Family Test is a useful addition to traditional measures of patient satisfaction. Level of evidence: II.

Exploring variation in patient access of post-discharge physiotherapy following total hip and knee arthroplasty under a choice based system in the UK: an observational cohort study

OBJECTIVES

To assess a targeted 'therapy as required' model of post-discharge outpatient physiotherapy provision. Specifically, we investigated what proportion of patients accessed post-discharge physiotherapy following total hip arthroplasty (THA) and total knee arthroplasty (TKA), whether accessing therapy was associated with post-arthroplasty patient reported outcomes and whether it was possible to predict which patients would access post-discharge physiotherapy from pre-operative data.

DESIGN

Prospective, observational, longitudinal cohort study.

SETTING

Single National Health Service orthopaedic teaching hospital in the UK.

PARTICIPANTS

1395 patients undergoing total hip arthroplasty and 1374 patients undergoing total knee arthroplasty.

PRIMARY AND SECONDARY OUTCOME MEASURES

Self-reported access of post-discharge physiotherapy, the Oxford Hip or Knee Score, EuroQol 5-dimension questionnaire and post-operative surgical episode satisfaction metric.

RESULTS

662 (48.2%) patients with TKA and 493 (35.3%) patients with THA accessed additional post-discharge physiotherapy. Patient-reported outcomes (p<0.001) and surgical episode satisfaction (p=0.001) in both THA and TKA were higher in patients that did not participate in post-discharge physiotherapy. Regression models using pre-operative symptom burden and demographic data predicted post-discharge therapy access with an accuracy of only 17% greater than chance in patients with THA and 7% greater than chance in patients with TKA.

CONCLUSIONS

In a choice-based service model of 'therapy as required' following hip and knee arthroplasty only a third of THA and half of TKA patients accessed post-discharge therapy. Patients who did not access physiotherapy reported greater post-operative outcomes. This variation in the need for post-discharge physiotherapy suggests that targeting of rehabilitation may be a cost-effective model, however it was not possible to reliably predict which patients would access post-discharge physiotherapy from pre-operative data.

Course of pain after total hip arthroplasty within a standardized pain management concept: a prospective study examining influence, correlation, and outcome of postoperative pain on 103 consecutive patients

INTRODUCTION

Postoperative pain management options are of great importance for patients undergoing total hip arthroplasty, as joint replacement surgery is reported to be one of the most painful surgical procedures. This study demonstrates pain outcome until 4 weeks postoperatively and evaluates factors influencing pain in the postoperative course after total hip arthroplasty.

MATERIALS AND METHODS

A total of 103 patients were included in this prospective cohort trial and underwent total hip arthroplasty. Postoperative pain was described using a numerical rating scale (NRS); demographic data and perioperative parameters were correlated with postoperative pain.

RESULTS

Evaluation of pain scores in the postoperative course showed a constant decrease in the first postoperative week (mean NRS 3.1 on day 1 to mean NRS 2.3 on day 8) and, then, a perpetual increase for 3 days (mean NRS 2.6 on day 9 to mean NRS 2.3 on day 12). Afterwards, a continuous pain-level decrease was stated (continuous to a mean NRS 0.9 on day 29). No correlation was found between the potential influencing factors sex, age, body mass index, duration of surgery, ASA score, and postoperative pain levels, but a high significant correlation could be stated for preoperative pain levels and postoperative pain intensity (pain while moving p < 0.02 to p < 0.05 depending on the time period "week 1 postoperatively", "week 2-4", or "week 1-4"; pain while resting p < 0.001, in all the measured time intervals, respectively).

CONCLUSION

Increasing pain levels after the first week postoperatively, for 3 days, are most likely to be caused by the change to more extensive mobilization and physiotherapy in the rehabilitation unit. No significant influence or correlation on the intensity of postoperative pain could be found while evaluating potential predictors except preoperative pain levels. Pain management has to take these findings into account in the future to further increase patients' satisfaction in the postoperative course after total hip arthroplasty and to adapt pain management programs.

Patient-reported outcome metrics following total knee arthroplasty are influenced differently by patients' body mass index

PURPOSE

This study investigated the impact of body mass index (BMI) on improvement in patient outcomes (pain, function, joint awareness, general health and satisfaction) following total knee arthroplasty (TKA).

METHODS

Data were obtained for primary TKAs performed at a single centre over a 12-month period. Data were collected pre-operatively and 12-month postoperatively with the Oxford Knee Score (OKS) measuring pain and function, the EQ-5D-3L measuring general health status, the Forgotten Joint Score-12 (FJS-12) measuring joint awareness and a single question on treatment satisfaction. Change in scores following surgery was compared across the BMI categories identified by the World Health Organization (< 25.0, 25.0-29.9, 30.0-34.9, 35.0-39.9 and ≥ 40.0). Differences in postoperative improvement between the BMI groups were analysed with an overall Kruskal-Wallis test, with post hoc pairwise comparisons between BMI groups with Mann-Whitney tests.

RESULTS

Of 402 patients [mean age 70.7 (SD 9.2); 55.2% women] 15.7% were normal weight (BMI < 25.0), 33.1% were overweight (BMI 25.0-29.9), 28.2% had class I obesity (BMI 30.0-34.9), 16.2% had class II obesity (BMI 35.0-39.9), and 7.0% had class III obesity (BMI ≥ 40.0). Postoperative change in OKS (n.s.) and EQ-5D-3L (n.s.) was not associated with BMI. Higher BMI group was associated with less improvement in FJS-12 scores (p = 0.010), reflecting a greater awareness of the operated joint during activity in the most obese patients. Treatment satisfaction was associated with BMI category (p = 0.029), with obese patients reporting less satisfaction.

CONCLUSIONS

In TKA patients, outcome parameters are influenced differently by BMI. Our study showed a negative impact of BMI on postoperative improvement in joint awareness and satisfaction scores, but there was no influence on pain, function or general health scores. This information may be useful in terms of setting expectations expectation in obese patients planning to undergo TKA.

LEVEL OF EVIDENCE

Level 1.

The Recovery Curve for the Patient-Reported Outcomes Measurement Information System Patient-Reported Physical Function and Pain Interference Computerized Adaptive Tests After Primary Total Knee Arthroplasty

BACKGROUND

We sought to characterize the typical recovery in physical function (PF) and pain interference (PI) after TKA using Patient-Reported Outcomes Measurement Information System (PROMIS) patient-reported outcome (PRO) measures.

METHODS

Ninety-one patients were enrolled into an institutional review board -approved prospective observational study. PROs were obtained preoperatively and postoperatively at 6 weeks, 3 months, 6 months, and 1 year. PROs included the PROMIS PF computerized adaptive test (CAT) and the PROMIS PI CAT. Generalized estimating equations were used to evaluate outcomes over time.

RESULTS

There was no difference in the preoperative and 6-week postoperative T-scores for the PF CAT (P = .410). However, all subsequent postoperative T-scores were greater than the preoperative T-score (all, P < 0.05). There was a significant reduction in PI CAT T-scores between the preoperative and all subsequent postoperative T-scores (all, P < .05). A clinically important difference in PF CAT T-scores (β = 5.44, 95% confidence interval 4.10-6.80; P < .001) and PI CAT T-scores (β = -7.46, 95% confidence interval -9.52 to -5.40; P < 0.001) was seen between the preoperative and 3-month postoperative visits. Sixty-three percent of the improvement in PF occurred by 3 months, and 89% had occurred by 6 months. The majority of reduction in PI (68%) occurred by 3 months and 90% had occurred by 6 months.

CONCLUSION

The greatest magnitude of improvement in both PF and PI occurred within the first 3 months. After 6 months, patients might expect modest improvements in PF and mild reductions of PI. Patients and surgeons should use this information for setting expectations, planning for recovery, and improving care.

No decline in high patient satisfaction after total hip arthroplasty at long-term follow-up

INTRODUCTION

Patient satisfaction is gaining popularity as an important outcome parameter in today's healthcare system and in particular in evaluating the outcome of joint arthroplasty. Total hip arthroplasty (THA) is a very successful procedure with reports on high patient satisfaction at short-term follow-up. Commonly used clinical outcome parameters remain good at long-term follow-up; however, whether this also accounts for patient satisfaction remains unclear. This study presents a prospective follow-up of patient satisfaction after THA, and a possible correlation with common outcome parameters was established.

METHODS

This study entails a concise follow-up of an earlier study on patient satisfaction 2.5 years after THA. Patient satisfaction was repeatedly measured with a visual analogue scale (VAS) after a mean follow-up of 13.5 (12.6-14.2) years in a prospective cohort of 147 patients (153 THAs). In addition, VAS pain and common clinical outcome parameters (WOMAC, OHS and SF-36) were also reassessed and were compared with short-term results after a mean follow-up of 2.5 (1.3-3.0) years.

RESULTS

At a follow-up of 13.5 (12.6-14.2) years, the median VAS for satisfaction was 95 (26-100) compared to a median VAS satisfaction of 98 (0-100) at earlier follow-up (p = 0.781). Overall, the clinical outcome parameters also remained good at long-term follow-up without significant changes. However, a rather low correlation with VAS satisfaction was encountered. Pain during activity showed the highest correlation (- 0.686) with VAS satisfaction.

CONCLUSION

Patient satisfaction after THA remains high after prolonged follow-up. Apparently patients do not get used to the successful results of their THA. A rather low correlation with common clinical outcome parameters suggests that patient satisfaction is a separate entity. Since patient satisfaction correlated best with pain during activity, this is probably the most important aspect in patient satisfaction. Measurement of patient satisfaction has additional value and may even replace some of the more commonly used questionnaires.

One year after proximal or distal periprosthetic fracture of the femur -two conditions with divergent outcomes?

INTRODUCTION

Arthroplasty of the hip and knee is 1 of the 20 most frequent operations in Germany. Periprosthetic fracture is one of the most feared complications following primary or revision arthroplasty. Present publication aims to analyse differences between patients with periprosthetic fracture around total knee arthroplasty (PFTKA) and patients with periprosthetic fracture around total hip arthroplasty (PFTHA) concerning demographics, clinical course, complications and return to pre-fracture mobility.

METHODS

Prospective single-centre observation study of periprosthetic femoral fractures with stable implants. Present subgroup analysis includes patients with PFTKA and PFTHA. All patients were treated with polyaxial angular stable plates using two standardized techniques: a minimally invasive percutaneous distal insertion technique and a mini-open technique. Data collection included implant- and operation-related information as well as demographics, clinical course, complications and return to pre-fracture mobility. Data were collected during a 12-month follow-up.

RESULTS

We were able to analyse the data of 73 patients. The PFTKA group had 37 patients with a mean age of 76 ± 10 years; 88% were female. After 1 year, 3 patients in this cohort had died; 68% of survivors had reached their pre-fracture mobility; 22% had undergone operative revisions for various reasons. The PFTHA cohort included 36 patients with a mean age of 80 ± 13 years, 72% were female. After 1 year, 9 patients had died in this cohort, 42% of survivors had reached their pre-fracture mobility. Non-operative complications occurred for 16% in the PFTKA group and 64% in the PFTHA group (p < 0.001). 11% had undergone operative revisions for various reasons, among them, two cases of nonunion but no primary infection.

CONCLUSION

On average, compared to the PFTHA patients, PFTKA patients were younger, underwent significantly lower rates of non-operative complications, had a tendency towards lower mortality, and returned to pre-fracture mobility at higher rates, although they tended to have more revisions when compared to treatment for PFTHA. Overall, when periprosthetic fractures of the femur were treated using polyaxial locking plate osteosynthesis, patients showed very low rates of nonunion and no primary infection.

Development of a clinical risk score for pain and function following total knee arthroplasty: results from the TRIO study

Objectives

The aim was to develop and validate a simple clinical prediction model, based on easily collected preoperative information, to identify patients at high risk of pain and functional disability 6 months after total knee arthroplasty (TKA).

Methods

This was a multicentre cohort study of patients from nine centres across the UK, who were undergoing a primary TKA for OA. Information on sociodemographic, psychosocial, clinical and quality-of-life measures were collected at recruitment. The primary outcome measure for this analysis was the Oxford knee score (OKS), measured 6 months postoperatively by postal questionnaire. Multivariable logistic regression was used to develop the model. Model performance (discrimination and calibration) and internal validity were assessed, and a simple clinical risk score was developed.

Results

Seven hundred and twenty-one participants (mean age 68.3 years; 53% female) provided data for the present analysis, and 14% had a poor outcome at 6 months. Key predictors were poor clinical status, widespread body pain, high expectation of postoperative pain and lack of active coping. The developed model based on these variables demonstrated good discrimination. At the optimal cut-off, the final model had a sensitivity of 83%, specificity of 61% and positive likelihood ratio of 2.11. Excellent agreement was found between observed and predicted outcomes, and there was no evidence of overfitting in the model.

Conclusion

We have developed and validated a clinical prediction model that can be used to identify patients at high risk of a poor outcome after TKA. This clinical risk score may be an aid to shared decision-making between patient and clinician.

Psychosocial predictors for outcome after total joint arthroplasty: a prospective comparison of hip and knee arthroplasty

BACKGROUND

As findings regarding predictors for good outcome after total joint arthroplasty are highly inconsistent, aim of this study was to investigate the influence of the psychosocial variables sense of coherence and social support as well as mental distress on physical outcome after surgery. It should be investigated if different predictors are important in patients after total hip arthroplasty (THA) compared to patients after total knee arthroplasty (TKA).

METHODS

In a prospective design, 44 patients undergoing THA and 61 patients undergoing TKA were examined presurgery and 6 and 12 weeks after surgery using WOMAC (disease-specific outcome), SF-36 (health-related quality of life), BSI (psychological distress), SOC-13 (sense of coherence), and F-SozU (social support). Changes over time were calculated by analyses of variance with repeated measures. Stepwise multiple linear regression analyses were computed for each group to predict scores of WOMAC total and all WOMAC subscales 12 weeks postoperatively.

RESULTS

THA as well as TKA patients experienced improvements in all parameters (effect sizes for WOMAC scores between η² = .387 and η² = .631) with THA patients showing even better results than TKA patients. WOMAC scores 12 weeks after surgery were predicted predominantly by WOMAC baseline scores in TKA with an amount of explained variance between 9.6 and 19.5%. In THA, 12-weeks WOMAC scores were predicted by baseline measures of psychosocial aspects (anxiety, sense of coherence, social support). In this group, predictors accounted for 17.1 to 31.6% of the variance.

CONCLUSIONS

Different predictors for outcome after total joint arthroplasty were obtained for THA and TKA patients. Although psychosocial aspects seemed to be less important in TKA patients, preoperatively, distressed patients of both groups should be offered interventions to reduce psychological distress to obtain better outcomes after surgery.

Evaluation of the Multi-Attribute Prioritisation Tool for Total Joint Replacement

Rationale aims and objectives

The demand for arthroplasty is increasing and will continue to rise with an ageing population. Obesity and lengthy waiting time for Total Joint Replacement (TJR) have been associated with poorer outcomes postoperatively. This study aimed to evaluate the Multi-Attribute Prioritisation Tool (MAPT) for TJR patients. The primary objective was to explore if patients prioritised by the MAPT had an improvement in score post-operative. Further to identify any relationship between MAPT score and length of time on the waiting list or obesity.

Method

This retrospective cohort study included 308 patients undergoing total hip (n = 114) or total knee (n = 194) arthroplasty. We examined preoperative and postoperative MAPT scores of patients who had total hip or total knee arthroplasty. After assessing the difference between postoperative and preoperative MAPT scores, patients scores were compared to BMI and waiting time classes. BMI was allocated to less than 30, 30-35, 35-40 and greater than 40. Duration of time on the waiting list was allocated to less than 6 months and greater than 6 months.

Results

THA and TKA patients MAPT scores improved from a preoperative score of 71.39-5.26 postoperative and 54.11 to 7.13 respectively. Patients whose MAPT scores placed them in the high priority category had a significant relationship with length of time on the waiting list (p < 0.01). There were no significant differences between length of time on the waiting list and improvement scores for low priority and middle priority patients. BMI had minimal effect on patients improvement score postoperative.

Conclusion

TJR patients prioritised by the MAPT questionnaire do experience pain relief as portrayed by a reduction in postoperative MAPT score. A longer length of time on the waiting list seems to effect the improvement a high priority patient can have postoperative.

Can Arthroplasty Stem INfluence Outcome? (CASINO): a randomized controlled equivalence trial of 125 mm versus 150 mm Exeter V40 stems in total hip arthroplasty

Background

The use of shorter length femoral stems during total hip arthroplasty has been suggested to accommodate wider patient femoral geometry and offer maximal bone preservation. However, cemented short-stem designs may increase the risk of varus stem malalignment and influence patient outcomes.

Methods/Design

CASINO is a multi-centre randomised equivalence trial that will recruit 220 patients undergoing total hip arthroplasty for osteoarthritis at two NHS hospitals in Scotland. Patients will be aged 45–80, undergoing unilateral primary hip arthroplasty, with no plan for contralateral procedure within the study timeframe, and able to comply with the protocol. Participants will be randomised to receive either a short (125 mm) or a standard (150 mm) Exeter V40 stem. The Contemporary acetabular component will be used in all cases. All implants will be cemented.

Patient pain, function and satisfaction will be assessed using change from baseline measurement in Oxford Hip Score, Forgotten Joint Score, EQ-5D, pain numerical rating scores, and patient satisfaction questionnaire at baseline and at 1 and 2 years following surgery. Radiographic assessment will evaluate stem position and will be appraised by independent reviewers. Patients will be blind to implant allocation.

Discussion

Stem length may be associated with outcome; however, we can find no randomised trial in which researchers investigated the effect of stem length on patient outcome following cemented total hip arthroplasty. The aim of this trial is to determine if the use of short cemented stems offers equivalent patient outcomes to those achieved following surgery with standard length stems.

Trial registration

International Standard Randomised Controlled Trial Number, ISRCTN13154542, Registered on 30 June 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2621-8) contains supplementary material, which is available to authorized users.

COST-UTILITY ANALYSIS OF PRIVATE CONTRACTING TO REDUCE PUBLIC WAITING TIMES FOR JOINT REPLACEMENT SURGERY

OBJECTIVES

Earlier treatment of publicly funded patients may achieve health gains that justify the additional costs of reducing waiting times. This study reports on the cost-effectiveness of implementing a private contracting model to meet alternative maximum waiting time targets for publicly funded patients undergoing total knee replacement surgery in Australia.

METHODS

A linked decision tree and cohort Markov model was developed and populated and validated using secondary data sources to represent the pathways, costs, and quality adjusted life-years (QALYs) gained of non-urgent patients with alternative waiting times for total knee replacement surgery to a maximum age of 100 years.

RESULTS

Assuming public waiting times are reduced through the purchase of private services, additional QALYs are gained at an incremental cost of less than $40,000. Value could be increased if lower private prices could be negotiated. Results are also sensitive to the rate of deterioration in function while waiting for surgery and the impact of functional status at the time of surgery on postsurgery outcomes.

CONCLUSIONS

More evidence on the value of expanded capacity or new models of care may inform new funding models to support such investments and reduced prices for new technologies, leading to more efficient and sustainable publicly funded healthcare systems.

Does physical activity change following hip and knee replacement? Matched case-control study evaluating Physical Activity Scale for the Elderly data from the Osteoarthritis Initiative

OBJECTIVES

To determine whether physical activity measured using the Physical Activity Scale for the Elderly (PASE), changes during the initial 24 months post-total hip (THR) or knee replacement (TKR), and how this compares to a matched non-arthroplasty cohort.

DESIGN

Case-controlled study analysis of a prospectively collected dataset.

SETTING

USA community-based.

PARTICIPANTS

116 people post-THR, 105 people post-TKR compared to 663 people who had not undergone THR or TKR, or had hip or knee osteoarthritis. Cohorts were age-, gender- and BMI-matched.

MAIN OUTCOME MEASURES

Physical activity assessed using the 12-item PASE at 12 and 24 months post operatively.

RESULTS

There was no significant difference in total PASE score between pre-operative to 12 months (mean: 136 vs 135 points; p=0.860) or 24 months following THR (mean: 136 vs 132 points; p=0.950). Whilst there was no significant difference in total PASE score from pre-operative to 12 months post-TKR (126 vs 121 points; p=0.930), by 24 months people following TKR reported significantly greater physical activity (126 vs 142 points; p=0.040). There was no statistically significant difference in physical activity between the normative matched and THR (p≥0.140) or TKR (p≥0.060) cohorts at 12 or 24 months post joint replacement.

CONCLUSIONS

Physical activity is not appreciably different to pre-operative levels at 12 or 24 months post-THR, but was greater at 24 months following TKR. Health promotion strategies are needed to encourage greater physical activity participation following joint replacement, and particularly targeting those who undergo THR.

Comparison of the extent to which total hip and total knee arthroplasty restore patient-reported physical function

OBJECTIVE

To evaluate the extent to which elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) for osteoarthritis (OA) restore normal patient-reported physical function in men and women.

METHODS

Pain and physical function (WOMAC-PF) were prospectively measured pre- and post-operatively. The relationship between surgical procedure and achieving physical function equivalent to age and sex-matched adults with no hip or knee joint problems was modeled using sex-specific logistic regression. Percent change in function was also compared between groups using sex-specific generalized linear models adjusted for age, BMI, pain, comorbid conditions, time from surgery, and subsequent surgery.

RESULTS

Individuals with pre- and post-operative WOMAC data were classified exclusively into either THA (287M:306F) or TKA (239M:424F) groups. The median follow-up was 476 (THA) and 474 (TKA) days for men, and 495 (THA) and 526 (TKA) days for women.

MAIN OUTCOME

women with THA compared with TKA were more likely to achieve a normal level of postoperative PF while there were no significant differences between procedures in men. Additional analyses: we found slightly lower preoperative PF in THA compared with TKA. This difference resolved postoperatively in men, but women who underwent THA reported greater improvement and better PF than those who had TKA.

CONCLUSION

In women, THA results in greater improvement in WOMAC-PF at approximately 1-year follow-up and better approximates physical function of community-dwelling older adults without OA than TKA does. In contrast, in men, a lack of between-group post-operative WOMAC-PF differences suggests that procedures result in a similar degree of improvement.

Predictors of physical functioning after total hip arthroplasty: a systematic review

OBJECTIVE

The objective of this systematic review of the literature was to identify the predictors of functional outcome after total hip arthroplasty (THA).

METHOD

A systematic literature search in Web of Science, CINAHL, EMBASE and PubMed was conducted on 23 June 2015. The articles were selected based on their quality, relevance and measurement of the predictive factor. The level of evidence of all studies was determined using the GRADE rating scheme.

RESULTS

The initial search resulted in 1092 citations. After application of the inclusion and exclusion criteria, 33 articles met our eligibility criteria and were graded. Included studies were classified as level of evidence low (11), moderate (17) or high (5). Of the included studies, 18 evaluated body mass index (BMI), 17 evaluated preoperative physical functions, 15 evaluated age, 15 evaluated gender and 13 evaluated comorbidity. There was strong evidence suggesting an association between BMI, age, comorbidity, preoperative physical functions and mental health with functional outcome after THA. There was weak evidence suggesting an association between quadriceps strength and education with functional outcome after THA. The evidence was inconsistent for associations with gender and socioeconomic status and functional outcome following THA. We found limited evidence suggesting that alcohol consumption, vitamin D insufficiency and allergies were predictors of functional outcome following THA.

CONCLUSIONS

We have identified multiple predictors of functional outcome after THA, which will enable general practitioners and orthopaedic surgeons to better predict the improvement in physical functioning for their patients with THA. They can use this information to provide patient-specific advice regarding the referral for THA and the expected outcomes after THA. Further research with consistent measurement tools, outcomes and duration of follow-up across studies is needed to confirm the influence of these factors.

Does the addition of hip strengthening exercises improve outcomes following total knee arthroplasty? A study protocol for a randomized trial

BACKGROUND

Total knee arthroplasty (TKA) is effective in reducing pain and improving function for end-stage knee osteoarthritis. However, muscle weakness and functional limitations persist despite assistance from post-operative rehabilitation programs that traditionally focus on quadriceps strengthening and range of movement exercises. Hip abductor muscle weakness is evident in knee osteoarthritis and hip muscle strengthening reduces knee pain in this group. Following TKA, people with weak hip abductor strength perform more poorly on measures of physical function. However, very little is known of the effectiveness of including hip abductor strengthening exercises in post-operative rehabilitation. The aim of this trial is to compare the effects of targeted hip abductor strengthening to those of traditional care in a TKA rehabilitation program on muscle strength, patient reported outcomes and functional performance measures.

METHODS/DESIGN

This protocol describes a single-blinded randomized controlled trial, where 104 participants referred for inpatient rehabilitation following TKA will be recruited. Participants will be randomized using computer-generated numbers to one of two groups: usual care or usual care with additional hip strengthening exercises. Participants will attend physiotherapy daily during their inpatient length of stay, and will then attend between six and eight physiotherapy sessions as an outpatient. Primary outcomes are isometric hip abductor strength and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Secondary outcomes are stair climb test, 6 min walk test, timed up and go, 40 m fast-paced walk test, 30 second chair stand test, isometric quadriceps strength, Lower Extremity Functional Scale (LEFS) and SF-12. Outcome measures will be recorded at baseline (admission to inpatient rehabilitation), and then 3 weeks, 6 weeks and 6 months post admission to rehabilitation.

DISCUSSION

The findings of this study will determine whether the addition of targeted hip strengthening to usual care rehabilitation improves physical performance and patient reported outcomes following TKA when compared to usual care rehabilitation. This will then determine whether targeted hip strengthening exercises should be included in traditional rehabilitation programs to improve the outcomes following total knee arthroplasty.

TRIAL REGISTRATION

The trial protocol was registered with the Australian Clinical Trial Registry ( ACTRN12615000863538 ) on 18 August 2015.

Factors that shape the patient's hospital experience and satisfaction with lower limb arthroplasty: an exploratory thematic analysis

OBJECTIVE

It is generally accepted that the patients' hospital experience can influence their overall satisfaction with the outcome of lower limb arthroplasty; however, little is known about the factors that shape the hospital experience. The aim of this study was to develop an understanding of what patients like and do not like about their hospital experience with a view to providing insight into where service improvements could have the potential to improve the patient experience and their satisfaction, and whether they would recommend the procedure.

DESIGN

A mixed methods (quan-QUAL) approach.

SETTING

Large regional teaching hospital.

PARTICIPANTS

216 patients who had completed a postoperative postal questionnaire at 12 months following total knee or total hip arthroplasty.

OUTCOME MEASURES

Overall satisfaction with the outcome of surgery, whether to recommend the procedure to another and the rating of patient hospital experience. Free text comments on the best and worst aspects of their hospital stay were evaluated using qualitative thematic analysis.

RESULTS

Overall, 77% of patients were satisfied with their surgery, 79% reported a good-excellent hospital experience and 85% would recommend the surgery to another. Qualitative analysis revealed clear themes relating to communication, pain relief and the process experience. Comments on positive aspects of the hospital experience were related to feeling well informed and consulted about their care. Comments on the worst aspects of care were related to being made to wait without explanation, moved to different wards and when they felt invisible to the healthcare staff caring for them.

CONCLUSIONS

Positive patient experiences were closely linked to effective patient-health professional interactions and logistics of the hospital processes. Within arthroplasty services, the patient experience of healthcare could be enhanced by further attention to concepts of patient-centred care. Practical examples of this include more focus on developing staff-patient communication and the avoidance of 'boarding' procedures.

Trajectories of Pain and Function after Primary Hip and Knee Arthroplasty: The ADAPT Cohort Study

Background and Purpose

Pain and function improve dramatically in the first three months after hip and knee arthroplasty but the trajectory after three months is less well described. It is also unclear how pre-operative pain and function influence short- and long-term recovery. We explored the trajectory of change in function and pain until and beyond 3-months post-operatively and the influence of pre-operative self-reported symptoms.

Methods

The study was a prospective cohort study of 164 patients undergoing primary hip (n = 80) or knee (n = 84) arthroplasty in the United Kingdom. Self-reported measures of pain and function using the Western Ontario and McMaster Universities Osteoarthritis index were collected pre-operatively and at 3 and 12 months post-operatively. Hip and knee arthroplasties were analysed separately, and patients were split into two groups: those with high or low symptoms pre-operatively. Multilevel regression models were used for each outcome (pain and function), and the trajectories of change were charted (0–3 months and 3–12 months).

Results

Hip: Most improvement occurred within the first 3 months following hip surgery and patients with worse pre-operative scores had greater changes. The mean changes observed between 3 and twelve months were statistically insignificant. One year after surgery, patients with worse pre-operative scores had post-operative outcomes similar to those observed among patients with less severe pre-operative symptoms. Knee: Most improvement occurred in the first 3 months following knee surgery with no significant change thereafter. Despite greater mean change during the first three months, patients with worse pre-operative scores had not ‘caught-up’ with those with less severe pre-operative symptoms 12 months after their surgery.

Conclusion

Most symptomatic improvement occurred within the first 3 months after surgery with no significant change between 3–12 months. Further investigations are now required to determine if patients with severe symptoms at the time of their knee arthroplasty have a different pre-surgical history than those with less severe symptoms and if they could benefit from earlier surgical intervention and tailored rehabilitation to achieve better post-operative patient-reported outcomes.

Making the Oxford Hip and Knee Scores meaningful at the patient level through normative scoring and registry data

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.

Methods

We accessed prospectively collected OHS and OKS data for patients undergoing lower limb joint arthroplasty at a single orthopaedic teaching hospital during a five-year period. T-scores were calculated based on the OHS and OKS distributions.

Results

Data were obtained from 3203 total hip arthroplasty (THA) patients and 2742 total knee arthroplasty (TKA) patients. The mean age of the patient was 68.0 years (sd 11.3, 58.4% women) in the THA group and in 70.2 (sd 9.4; 57.5% women) in the TKA group. T-scores were calculated for age and gender subgroups by operation. Different T-score thresholds are seen at different time points pre and post surgery. Values are further stratified by operation (THA/TKA) age and gender.

Conclusions

Normative data interpretation requires a fundamental shift in the thinking as to the use of the Oxford Scores. Instead of reporting actual score points, the patient is rated by their relative position within the group of all patients undergoing the same procedure. It is proposed that this form of transformation is beneficial (a) for more appropriately comparing different patient cohorts and (b) informing an individual patient how they are progressing compared with others of their age and gender.

Cite this article: Bone Joint Res 2015;4:137–144

Patients' perceptions of physical activity before and after joint replacement: a systematic review with meta-ethnographic analysis

BACKGROUND

It has been perceived that people following total hip arthroplasty (THA) or total knee arthroplasty (TKA) have the capability, with reduced pain, to increase their levels of physical activity.

OBJECTIVES

To determine the attitudes and perceptions of people awaiting or having undergone THA or TKA to physical activity post-arthroplasty and to identify potential facilitators or barriers to engage in active living and physical activity pursuits.

METHODS

Systematic review of published and unpublished databases was undertaken from their inception to November 2014. Studies exploring the attitudes and perceptions of people awaiting or having undergone THA or TKA to physical activity post-arthroplasty were included. Data were analysed through a meta-ethnography approach.

RESULTS

From 528 citations, 13 papers were eligible, sampling 282 people post-THA or TKA. The literature was judged moderate to high quality. Following THA and TKA, people either wished to return to their pre-pathology level of physical activity or simply be able to engage in less physically demanding activities that are meaningful to them and their lifestyles. Barriers to engaging in higher levels of physical activity were largely related to limited information, which culminated in fear surrounding 'doing the right thing' both for individual's recovery and the longevity of the joint replacement.

CONCLUSIONS

While many people post-THA or TKA wish to return to pre-pathological physical activity status, there is limited interest in actually undertaking greater levels of physical activity post-arthroplasty either for pleasure or health gains. Improvement in education and awareness of this may be key drivers to improve habitualisation of physical activity post-arthroplasty.

TRIAL REGISTRATION NUMBER

CRD42014014995.

Dealing with the predicted increase in demand for revision total knee arthroplasty: challenges, risks and opportunities

Worldwide rates of primary and revision total knee arthroplasty (TKA) are rising due to increased longevity of the population and the burden of osteoarthritis. Revision TKA is a technically demanding procedure generating outcomes which are reported to be inferior to those of primary knee arthroplasty, and with a higher risk of complication. Overall, the rate of revision after primary arthroplasty is low, but the number of patients currently living with a TKA suggests a large potential revision healthcare burden. Many patients are now outliving their prosthesis, and consideration must be given to how we are to provide the necessary capacity to meet the rising demand for revision surgery and how to maximise patient outcomes. The purpose of this review was to examine the epidemiology of, and risk factors for, revision knee arthroplasty, and to discuss factors that may enhance patient outcomes.

Clinical improvement and satisfaction after total joint replacement: a prospective 12-month evaluation on the patients' perspective

PURPOSE

To determine short-term improvements, satisfaction rates and the patient acceptable symptom state (PASS) after total joint replacement (TJR) for different patient-reported outcome measures (PROMs).

METHODS

This prospective cohort study included 426 consecutive patients undergoing total hip (n = 193) or knee arthroplasty (n = 233). The following PROMs were completed before TJR, and at 3, 6 and 12 months after surgery, respectively: WOMAC, Oxford Hip or Knee Score, Lower Extremity Functional Scale, University of California at Los Angeles (UCLA) activity scale and EuroQol-5 dimension (EQ-5D). Satisfaction rates and the PASS thresholds were also assessed.

RESULTS

THA patients improved quicker and achieved higher outcome scores than TKA patients. Comorbidities according to the Sangha score were moderately correlated with all PROM values in an inverse direction at all time points (r = -0.27 to -0.47, p < 0.01) in both groups. Satisfaction with the result of surgery improved over time. At 12 months, more than 90 % of the patients were satisfied or very satisfied with the achieved result. The THA group showed a higher proportion of very satisfied patients than the TKA group at all time points. PASS thresholds increased over time for all PROMs except for the UCLA and the EQ-5D in TKA patients.

CONCLUSIONS

More than 90 % of the patients will be satisfied 1 year after TJR. THA patients recover faster than TKA patients, i.e., they achieve higher PROM values at earlier follow-up time points. Cutoff values defining a successful result in terms of the PASS could be defined for all PROMs at different time points and can serve as reference for future studies and patient-oriented follow-ups.

Gait assessment as a functional outcome measure in total knee arthroplasty: a cross-sectional study

Background

The aim of the study was to assess gait in total knee arthroplasty (TKA) patients, using a technique that can to be used on a routine basis in a busy orthopaedic clinic.

Methods

A total of 103 subjects were recruited: 29 pre-op TKA patients; 17 TKA patients at 8 weeks post-op; 28 TKA patients at 52 weeks post-op; and 29 age-matched controls. Inertial measurement units (IMUs) were used to assess gait. Limb segment angles, knee angle and temporal parameters of gait were calculated. Specific gait parameters were quantified, and data analysed using MANOVA and discriminant analysis.

Results

The gait of TKA patients as a group was only slightly improved at 12 months when compared with the pre-operative group, and both groups were significantly different to controls in several variables. Knee flexion range in stance was the most important variable in discriminating between patients and controls; knee flexion range in swing was the only variable that showed a significant difference between pre- and post-operative patients. When considered individually, only 1/29 patient was within the normal range for this variable pre-operatively, but 9/28 patients were within the normal range 12 months post-operatively.

Conclusions

Even after 12 months after surgery, many TKA patients have not improved their gait relative to pre-operative patients. Routine gait assessment may be used to guide post-operative rehabilitation, and to develop strategies to improve mobility of these patients.

Implant design influences patient outcome after total knee arthroplasty: a prospective double-blind randomised controlled trial

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.

Chinese patients' satisfaction with total hip arthroplasty: what is important and dissatisfactory?

Through validated self-administered questionnaires, we conducted a retrospective investigation in 818 patients (1009 hips) who underwent primary THA, to collect data on overall satisfaction plus satisfaction and importance rating for 16 specific functions and issues. Overall, 8.1% patients were dissatisfied with the surgery. The top 3 important items are pain relief, squatting, and walking. The top 3 dissatisfactory items are jogging, squatting, and rising after squatting. The strongest risk factors for dissatisfaction with walking were pain (6.1×), muscle weakness(3.7×), and LLD (3.3×). The strongest risk factors for dissatisfaction with squatting were low postoperative HHS ROM (3.7×) and muscle weakness (2.6×). For Chinese patients, ROM, muscle strength and LLD are very important.

Factors influencing initial cup stability in total hip arthroplasty

BACKGROUND

One of the main goals in total hip replacement is to preserve the integrity of the hip kinematics, by well positioning the cup and to make sure its initial stability is congruent and attained. Achieving the latter is not trivial.

METHODS

A finite element model of the cup-bone interface simulating a realistic insertion and analysis of different scenarios of cup penetration, insertion, under-reaming and loading is investigated to determine certain measurable factors sensitivity to stress-strain outcome. The insertion force during hammering and its relation to the cup penetration during implantation is also investigated with the goal of determining the initial stability of the acetabular cup during total hip arthroplasty. The mathematical model was run in various configurations to simulate 1 and 2mm of under-reaming at various imposed insertion distances to mimic hammering and insertion of cup insertion into the pelvis. Surface contact and micromotion at the cup-bone interface were evaluated after simulated cup insertion and post-operative loading conditions.

FINDINGS

The results suggest a direct correlation between under-reaming and insertion force used to insert the acetabular cup on the micromotion and fixation at the cup-bone interface.

INTERPRETATION

While increased under-reaming and insertion force result in an increase amount of stability at the interface, approximately the same percentage of surface contact and micromotion reduction can be achieved with less insertion force. We need to exercise caution to determine the optimal configuration which achieves a good conformity without approaching the yield strength for bone.