Activity-related pain and sensitization predict within- and between-person pain experience in people with knee osteoarthritis: An ecological momentary assessment study.

Background and objectives: Knee Osteoarthritis (OA) is a prevalent musculoskeletal condition that often results in pain and disability. Determining factors predicting variability in pain experience is critical to improving clinical outcomes. Underlying pain sensitization and its clinical manifestations, such as activity-related pain, may better predict the knee OA pain experience. This study aimed to determine whether Quantitative Sensory Testing (QST) derived sensitization measures and activity-related pain predict knee OA pain experiences collected via smartphone ecological momentary assessment (EMA). Design: Individuals with knee OA were recruited from an urban community in New Zealand. Those eligible to participate underwent baseline QST with clinical measures of activity-related pain also being collected. The knee OA pain experience was collected via smartphone EMA three times daily for two weeks. Mixed effects location scale models were developed using a multilevel modelling approach. Results: Eighty-six participants with knee OA participated in the study. Mean age was 67.3 years, with most of the participants being female (64%) and New Zealand European (90.6%). Activity-related pain predicted worse and more variable pain intensity, pain interference, and bothersomeness outcomes within and between individuals with knee OA. Widespread cold hyperalgesia and local mechanical hyperalgesia were shown to predict higher within-person variability in pain intensity and pain interference respectively, while mechanical temporal summation predicted less within-person variability in pain intensity and interference. Discussion: Those demonstrating activity-related pain and sensitization could be at risk of experiencing worse and more variable knee OA pain in the subsequent weeks. Testing for sensitization in clinical practice could therefore identify those at greatest risk of higher and more variable knee OA pain experiences and in greatest need of treatment. Larger validation studies are required, which include individuals with more severe knee OA.

Upper-Limb High-Intensity Interval Training or Passive Heat Therapy to Optimize Cardiorespiratory Fitness Prior to Total Hip or Knee Arthroplasty: A Randomized Controlled Trial.

OBJECTIVE: Preoperative exercise training, or prehabilitation, aims to optimize cardiorespiratory fitness before surgery to reduce the risk of adverse perioperative events and delayed recovery. However, traditional exercise such as walking and cycling can be difficult for people with degenerative joint diseases of the lower limbs, such as osteoarthritis. The purpose of this study was to compare the effect of three low-impact interventions on cardiorespiratory fitness, physical function, and subjective health before total hip or knee arthroplasty. METHODS: This was a randomized controlled trial involving 93 participants with severe knee or hip osteoarthritis awaiting joint replacement surgery. Participants underwent cardiopulmonary exercise testing (to measure peak oxygen consumption [ V ̇ $$ \dot{V} $$ O2 ]), then were randomized to heat therapy (Heat; 20-30 min immersed in 40°C water followed by ~15 min light-resistance exercise), high-intensity interval training (HIIT; 6-8 × 60 s intervals on a cross-trainer or arm ergometer at ~90%-100% peak V ̇ $$ \dot{V} $$ O2 ), or home-based exercise (Home; ~15 min light-resistance exercise); for up to 36 sessions (3 sessions per week for 12 weeks). RESULTS: Peak V ̇ $$ \dot{V} $$ O2 increased by 16% across HIIT and to a greater extent than Heat (+2.5 mL × min-1 × kg-1 [95% CI: 0.5-4.4], P = 0.009) and Home (+3.2 mL × min-1 × kg-1 [1.2-5.2], P = 0.001). The anaerobic threshold increased across HIIT (+1.5 mL × min-1 × kg-1 [0.7-2.3], P < 0.001) and Heat (+1.2 mL × min-1 × kg-1 [0.4-1.9], P = 0.004), but not Home (-0.5 mL × min-1 × kg-1 [-1.3 to 0.3], P = 0.248). Subjective severity of osteoarthritis was unchanged with any intervention (P ≥ 0.250). CONCLUSION: Heat therapy and HIIT improved indices of cardiorespiratory fitness preoperatively in patients who have difficulty performing lower-limb exercise.

The increasing complexity of femoral fragility fractures: incidence, fracture patterns and management over a 10-year period.

INTRODUCTION: The purpose of this study was to determine whether there have been changes in the numbers and complexity of femoral fragility fractures presenting to our department over a period of 10 years. METHODS: Patients >60 years presenting with femoral fragility fractures to our institution in 2018-2019 (397 fractures) were compared with respect to demographic data, incidence rates, fracture classification and surgical management with a historical cohort from 2009-2010 (335 fractures). Pathological and high velocity fractures were excluded. RESULTS: The gender proportion and average age (83.1 vs. 82.7 years) was unchanged. The number of femoral fractures increased by 19% but the overall incidence in people >60 years fell by 6% (p = 0.41). The proportion of unstable trochanteric fractures (31A2 and A3) increased from 22% to 55% (p < 0.001). The proportion of displaced intracapsular fractures increased from 53% to 72% (p < 0.001). The incidence of stable trochanteric fractures fell from 12.4 to 7.3/10,000 patients>60 years (p = 0.0006) while the incidence of unstable trochanteric fractures (31A2 and 31A3) increased from 3.5 to 8.9/10,000 patients >60 years (p < 0.0001). The proportion of trochanteric fractures treated with an intramedullary (IM) nail increased from 9% to 35% (p = 0.0001). The number of shaft and distal femoral fractures increased by 41% although the incidence did not change significantly. Periprosthetic fractures comprised 70% of femoral shaft fractures in both cohorts. CONCLUSIONS: The increasing number and complexity of femoral fragility fractures, especially unstable trochanteric fractures and periprosthetic fractures, is likely to have an impact on implant use, theatre time and cost.

Acute and adaptive cardiovascular and metabolic effects of passive heat therapy or high-intensity interval training in patients with severe lower-limb osteoarthritis.

Exercise is painful and difficult to perform for patients with severe lower-limb osteoarthritis; consequently, reduced physical activity contributes to increased cardiometabolic disease risk. The aim of this study was to characterize the acute and adaptive cardiovascular and metabolic effects of two low or no impact therapies in patients with severe lower-limb osteoarthritis: passive heat therapy (Heat) and high-intensity interval training (HIIT) utilizing primarily the unaffected limbs, compared to a control intervention of home-based exercise (Home). Participants completed up to 12 weeks of either Heat (20-30 min immersed in 40°C water followed by ~15-min light resistance exercise), HIIT (6-8 × 60-s intervals on a cross-trainer or arm ergometer at ~90-100% peak V ̇ $$ \dot{V} $$ O2 ) or Home (~15-min light resistance exercise); all 3 sessions/week. Reductions in systolic (12 & 10 mm Hg), diastolic (7 & 4 mm Hg), and mean arterial (8 & 6 mm Hg) blood pressure (BP) were observed following one bout of Heat or HIIT exposure, lasting for the duration of the 20-min monitoring period. Across the interventions (i.e., 12 weeks), resting systolic BP and diastolic BP decreased with Heat (-9 & -4 mm Hg; p < 0.001) and HIIT (-7 & -3 mm Hg; p ≤ 0.011), but not Home (0 & 0 mm Hg; p ≥ 0.785). The systolic and diastolic BP responses to an acute exposure of Heat or HIIT in the first intervention session were moderately correlated with adaptive responses across the intervention (r ≥ 0.54, p ≤ 0.005). Neither intervention improved indices of glycemic control (p = 0.310). In summary, both Heat and HIIT induced potent immediate and adaptive hypotensive effects, and the acute response was moderately predictive of the long-term response.

Experiences and Perceptions of Using Smartphone Ecological Momentary Assessment for Reporting Knee Osteoarthritis Pain and Symptoms.

BACKGROUND: Knee osteoarthritis (OA) is a prevalent, painful, and disabling musculoskeletal condition. One method that could more accurately monitor the pain associated with knee OA is ecological momentary assessment (EMA) using a smartphone. OBJECTIVES: The aim of this study was to explore participant experiences and perceptions of using smartphone EMA as a way of communicating knee OA pain and symptoms following participating in a 2-week smartphone EMA study. MATERIALS AND METHODS: Using a maximum variation sampling method, participants were invited to share their thoughts and opinions in semistructured focus group interviews. Interviews were recorded and transcribed verbatim before thematic analysis using the general inductive approach. RESULTS: A total of 20 participants participated in 6 focus groups. Three themes and 7 subthemes were identified from the data. Identified themes included: user experience of smartphone EMA, data quality of smartphone EMA, and practical aspects of smartphone EMA. DISCUSSION: Overall, smartphone EMA was deemed as being an acceptable method for monitoring pain and symptoms associated with knee OA. These findings will assist researchers in designing future EMA studies alongside clinicians implementing smartphone EMA into practice. PERSPECTIVE: This study highlights that smartphone EMA is an acceptable method for capturing pain-related symptoms and experiences of those expereiencing knee OA. Future EMA studies should ensure design features are considered that reduce missing data and limit the responder burden to improve data quality.

Are the outcomes of relative motion extension orthoses non-inferior and cost-effective compared with dynamic extension orthoses for management of zones V-VI finger extensor tendon repairs: A randomized controlled trial.

INTRODUCTION: There is no comparative evidence for relative motion extension (RME) orthosis with dynamic wrist-hand-finger-orthosis (WHFO) management of zones V-VI extensor tendon repairs. PURPOSE OF THE STUDY: To determine if RME with wrist-hand-orthosis (RME plus) is noninferior to dynamic WHFO for these zones in clinical outcomes. STUDY DESIGN: Randomized controlled non-inferiority trial. METHODS: Skilled hand therapists managed 37 participants (95% male; mean age 39 years, SD 18) with repaired zones V-VI extensor tendons randomized to RME plus (n = 19) or dynamic WHFO (n = 18). The primary outcome of percentage of total active motion (%TAM) and secondary outcomes of satisfaction, function, and quality of life were measured at week-6 and -12 postoperatively; percentage grip strength (%Grip), complication rates, and cost data at week-12. Following the intention-to-treat principle non-inferiority was assessed using linear regression analysis (5% significance) and adjusted for injury complexity factors with an analysis of costs performed. RESULTS: RME plus was noninferior for %TAM at week-6 (adjusted estimates 2.5; 95% CI -9.0 to 14.0), %TAM at week-12 (0.3; -6.8 to 7.5), therapy satisfaction at week-6 and -12, and orthosis satisfaction, QuickDASH, and %Grip at week-12. Per protocol analysis yielded 2 tendon ruptures in the RME plus orthoses and 1 in the dynamic WHFO. There were no differences in health system and societal cost, or quality-adjusted life years. DISCUSSION: RME plus orthosis wearers had greater injury complexity than those in dynamic WHFOs, with overall rupture rate for both groups comparatively more than reported by others; however, percentage %TAM was comparable. The number of participants needed was underestimated, so risk of chance findings should be considered. CONCLUSIONS: RME plus management of finger zones V-VI extensor tendon repairs is non-inferior to dynamic WHFO in %TAM, therapy and orthotic satisfaction, QuickDASH, and %Grip. Major costs associated with this injury are related to lost work time.

Are Ecological Momentary Assessments of Pain Valid and Reliable? A Systematic Review and Meta-analysis.

OBJECTIVES: This systematic review and meta-analysis aimed to determine the level of evidence for the psychometric properties of Ecological Momentary Assessment (EMA) in populations with persistent pain. MATERIALS AND METHODS: Five databases were searched from 1980 to December 2021. Two reviewers independently screened the titles, abstracts, and full text, extracted data, and assessed adherence to reporting standards and methodological rigor before evaluating the quality of evidence. A meta-analysis, including the pooling of correlations for the relevant EMA pain outcomes, was completed. RESULTS: Overall, 3270 studies were identified, with 14 studies meeting inclusion criteria. Meta-analyses confirmed good to excellent relationships demonstrated between EMA and recalled pain intensity and interference across different timeframes. Many of the included studies did not fully adhere to recommended reporting standards, and the quality of included studies was either doubtful or inadequate due to methodological flaws. The level of evidence for measurement properties of pain outcomes was low for the criterion validity of pain intensity and interference and very low for reliability and construct validity of pain intensity and interference. DISCUSSION: Ecological momentary assessment of pain experience appears both valid and reliable. Although the levels of evidence were low or very low, these findings provide preliminary support for the use of EMA in clinical practice and research settings. Potential strengths of EMA include providing measures with greater ecological validity while also reducing recall bias, both pertinent in pain outcome measurement. More research, including higher-quality studies, is needed to demonstrate further support for EMA, including the need for establishing other types of validity.

Physiological relationship between cardiorespiratory fitness and fitness for surgery: a narrative review.

Epidemiological evidence has highlighted a strong relationship between cardiorespiratory fitness and surgical outcomes; specifically, fitter patients possess heightened resilience to withstand the surgical stress response. This narrative review draws on exercise and surgical physiology research to discuss and hypothesise the potential mechanisms by which higher fitness affords perioperative benefit. A higher fitness, as indicated by higher peak rate of oxygen consumption and ability to sustain metabolic homeostasis (i.e. higher anaerobic threshold) is beneficial postoperatively when metabolic demands are increased. However, the associated adaptations with higher fitness, and the related participation in regular exercise or physical activity, might also underpin the observed perioperative benefit through a process of hormesis, a protective adaptive response to the moderate and intermittent stress of exercise. Potential mediators discussed include greater antioxidant capacity, metabolic flexibility, glycaemic control, lean body mass, and improved mood.

Reliability, Validity, Responsiveness, and Minimum Important Change of the Stair Climb Test in Adults With Hip and Knee Osteoarthritis.

OBJECTIVE: The Osteoarthritis Research Society International (OARSI) recommends assessment of physical function using a performance-based test of stair negotiation but was unable to recommend any specific test. We assessed the reliability, validity, responsiveness, measurement error, and minimum important change (MIC) of the 6-step timed Stair Climb Test (SCT). METHODS: We used pooled data from 397 participants with hip or knee osteoarthritis (54% women) from 4 clinical trials (86% retained at 12-week follow-up). Construct validity was assessed by testing 6 a priori hypotheses against other OARSI-recommended physical function measures. A self-reported Global Rating of Change scale was used to classify participants as worsened, improved, and stable. Participants who worsened in physical function were excluded from all analyses. Responsiveness and MIC were assessed using multiple anchor-based and distribution-based approaches. Test-retest reliability, standard error of measurement (SEM), and smallest detectable change (SDC) were assessed on stable participants. RESULTS: Five of 6 hypotheses (83%) for construct validity were met. Test-retest reliability was excellent (intraclass correlation coefficient2,1 0.83; 95% confidence interval 0.71-0.90). The SEM and SDC values were 0.44 and 1.21 seconds, respectively. We did not find adequate support for responsiveness. The MIC values ranged from 0.78 to 1.95 seconds using different approaches (median 1.37 seconds). CONCLUSION: The 6-step timed SCT adequately assesses the construct of physical function in individuals with hip or knee osteoarthritis with excellent 12-week test-retest reliability. However, support for its responsiveness was inadequate to recommend its use as an outcome measure in people with osteoarthritis for research and clinical practice.

Activity-related pain predicts pain and functional outcomes in people with knee osteoarthritis: A longitudinal study.

Knee Osteoarthritis (OA) is a prevalent musculoskeletal condition, commonly resulting in pain and disability. However, pain and disability in this population are poorly related with the degree of structural joint damage. Underlying pain mechanisms, including activity-related pain and sensitization assessed via Quantitative Sensory Testing (QST), may better predict pain and functional outcomes of those with knee OA. Therefore, the aim of this study was to explore whether activity-related pain and sensitization assessed via QST predict future pain, function, fatigue, physical performance and quality of life outcomes in those living in the community with knee OA. Eighty-six participants with knee OA were recruited in Dunedin, New Zealand. Those eligible to participate underwent baseline testing including QST as well as measures of activity-related pain including Movement-evoked Pain (MEP) and Sensitivity to Physical Activity (SPA). Outcome measures exploring pain, function, fatigue and quality of life outcomes were collected at baseline, and two follow-up periods (two and nine weeks). Univariable linear regression models were developed followed by multivariable linear regression models for each prognostic marker adjusting for age, gender, BMI, OA duration, baseline pain intensity and socioeconomic status. Activity-related measures of pain, including MEP and SPA, demonstrated predictive associations with pain and functional outcomes prospectively in those with knee OA. Therefore, those demonstrating activity-related pain are at future risk of greater pain, disability and reduced quality of life. Larger, externally validated longitudinal studies are required which include individuals with more severe knee OA.

Total Hip and Knee Arthroplasties Are Highly Cost-Effective Procedures: The Importance of Duration of Follow-Up.

BACKGROUND: Total hip and knee arthroplasties (THA/TKA) are clinically effective but high cost procedures. The aim of this study is to perform a cost-effectiveness analysis of THA and TKA in the New Zealand (NZ) healthcare system. METHODS: Data were collected from 713 patients undergoing THA and 520 patients undergoing TKA at our local public hospital. SF-6D utility values were obtained from participants preoperatively and 1-year postoperatively, and deaths and any revision surgeries from patient records and the New Zealand Joint Registry at minimum 8-year follow-up. A continuous-time state-transition simulation model was used to estimate costs and health gains to 15 years. Quality-adjusted life years (QALYs), treatment costs, and incremental cost-effectiveness ratios (ICERs) were calculated to determine cost effectiveness. ICERs below NZ gross domestic product (GDP; NZ$60 600) and 0.5 times GDP per capita were considered "cost effective" and "highly cost effective" respectively. RESULTS: Cumulative health gains were 2.8 QALYs (THA) and 2.3 QALYs (TKA) over 15 years. Cost effectiveness improved from ICERs of NZ$74,400 (THA) and NZ$93,000 (TKA) at 1 year to NZ$6000 (THA) and NZ$7500 (TKA) at 15 years. THA and TKA were cost effective after 2 years and highly cost effective after 3 years. QALY gains and cost effectiveness were greater in patients with worse preoperative functional status and younger age. CONCLUSION: THA and TKA are highly cost-effective procedures over longer term horizons. Although preoperative status and age were associated with cost effectiveness, both THA and TKA remained cost effective in patients with less severe preoperative scores and older ages.

The Relationship Between Preoperative Oxford Hip and Knee Score and Change in Health-Related Quality of Life After Total Hip and Total Knee Arthroplasty: Can It Help Inform Rationing Decisions?

BACKGROUND: In countries with publicly funded health care, there is an increasing need for explicit rationing for total joint arthroplasty (TJA). The Oxford Hip and Knee Scores (OHS/OKS) have been used to set access thresholds for TJA despite not being developed for that purpose. The aim of this study was to determine whether preoperative OHS/OKS can aid rationing decisions by investigating the changes in general health-related quality of life after TJA. METHODS: OHS/OKS, Short Form-12, and Short Form-6D (SF-6D) scores were collected preoperatively and at 1 year postoperatively in a cohort of patients undergoing total hip arthroplasty (THA; n = 713) and total knee arthroplasty (TKA; n = 520). The association between preoperative OHS/OKS and postoperative score and the change in OHS/OKS and SF-6D was investigated, adjusting for age and gender. RESULTS: The mean Oxford scores improved from 13.9 to 40.7 (OHS) and 15.6 to 37.4 (OKS). The mean SF-6D improved after THA (0.53 to 0.80) and TKA (0.56 to 0.78) (all P < .0001). Poorer preoperative Oxford scores were associated with poorer postoperative OHS/OKS and SF-6D but larger improvements. For every 5 points lower preoperative OHS/OKS, the postoperative SF-6D score was worse by a margin of 0.019 (THA) and 0.023 (TKA). CONCLUSIONS: Preoperative OHS/OKS can help inform rationing decisions. A lower preoperative OHS/OKS will result in greater gains but a lower final outcome score in general health-related quality of life.

Acetabular Liner Dissociation: A Comparative Study of Two Contemporary Uncemented Acetabular Components.

BACKGROUND: There are a number of reports of polyethylene liner dissociation of third-generation modular acetabular components. This study compares our experience with 2 contemporary systems to determine whether this is an implant- or class-specific problem. METHODS: This is a single-center retrospective study of 961 primary total hip arthroplasties using 2 third-generation modular cementless acetabular shells: Pinnacle (535) and R3 (426) with a polyethylene liner. Details of all revisions were obtained from local databases and the New Zealand Joint Registry. Kaplan-Meier survival curves were calculated for all-cause revision, acetabular reoperation (including liner exchange), and liner dissociation. RESULTS: There were 17 revisions in group 1 (Pinnacle; DePuy Synthes): 17 for recurrent dislocation, 6 for liner dissociations (1.12%), 3 for femoral loosening, and one for deep infection. In group 2 (R3; Smith and Nephew), there were 4 revision procedures: one for infection, 2 for dislocation, and one femoral revision for periprosthetic fracture. There were significantly higher proportions revised in group 1 for all-cause revision, acetabular reoperation, and dissociation (P = .024 to 0.038). The 7-year survival for all-cause revision was 96.1% for Pinnacle and 99.0% for R3 (P = .022), and that in the acetabular reoperation group was 96.9% for Pinnacle and 99.3% for R3 (P = .035). CONCLUSIONS: There was a higher revision rate for the Pinnacle acetabular component than for the R3 at 7 years. This was mainly due to polyethylene liner dissociation that can occur early or late. It appears to be a problem specific to the Pinnacle cup design rather than a feature of similar third-generation acetabular components.

The Functional Outcomes of Patients With Knee Osteoarthritis Managed Nonoperatively at the Joint Clinic at 5-Year Follow-Up: Does Surgical Avoidance Mean Success?

BACKGROUND: Nonoperative management of patients with knee osteoarthritis (OA) through multidisciplinary programs may delay or reduce the need for total knee arthroplasty (TKA). However, avoidance of surgery may not represent success for the patient. METHODS: A cohort of 120 patients with knee OA managed with at least 6 months of supervised nonoperative treatment coordinated through the Joint Clinic were reviewed at 5 years. Outcomes including Oxford knee score (OKS), Short Form 12 (SF-12), and SF-6D and other measures including analgesia use, global change, and perception of need for surgery were collected and compared with those from the cohort who had undergone TKA. RESULTS: Seventy (62.5%) surviving patients were still being managed nonoperatively. There was no significant change in any outcome score (OKS, SF-12 physical component score, SF-12 mental component score, SF-6D) (P = .26 to .84). Forty-two patients had undergone TKA with mean time to surgery 29.0 months (range, 9-69 months). In this group, the mean OKS fell from 17.9 at baseline to 10.3 (range, 3-21) preoperatively (P < .0001) and at 5 years there was a significant improvement from baseline in OKS, SF-12 physical component score, and SF-6D scores (P < .0001). All outcome scores and change in scores were significantly higher for the surgical group (all P < .001). CONCLUSION: Although a high proportion of patients with knee OA have avoided surgery at 5 years, their outcomes show no improvement from baseline and are poorer than those who have undergone TKA. Avoidance of surgery should not necessarily be regarded as an indicator of success of nonoperative treatment for the patient.

Non-resident orthopaedic admissions to Dunedin Hospital 1997 to 2017 and Southland Hospital 2011 to 2017.

AIMS: The purpose of this study is to audit the numbers of non-residents requiring orthopaedic admission to Dunedin and Southland Hospitals and determine the effects of increasing tourist numbers on healthcare resources. METHOD: All non-resident orthopaedic admissions to Dunedin Hospital from January 2005 to December 2017 and Invercargill Hospital from January 2011 to December 2017 were analysed with respect to country of residence, mechanism of injury, primary diagnosis and case weights consumed. The results were combined with figures from 1997-2004 to give a 21-year series for Dunedin Hospital. RESULTS: There has been a significant increase in the number of admissions and case weights (CW) over the past 21 years at Dunedin Hospital (p<0.001). The most common mechanisms of injury were snow sports at Dunedin Hospital and falls for Southland Hospital. Between 2011 and 2017 there were on average 50 non-resident admissions per year (92.9 CW/year) to Dunedin Hospital and 74 admissions (120.7 CW/year) in Southland. CONCLUSION: Increasing tourist numbers have resulted in an increase number of orthopaedic admissions to Dunedin Hospital over the last two decades although it remains a small proportion of the total workload. Southland Hospital is relatively more affected. These patients represent an annual cost in excess of $1,000,000 to Southern DHB.

National Referral Prioritization tool for first specialist assessment: results of a pilot study in orthopaedic surgery.

BACKGROUND: Most public hospitals are receiving more referrals for first specialist assessment than they have capacity to see. Traditional priority categories are too broad for effective discrimination. In New Zealand (NZ) explicit prioritization is required by legislation and supported by the Medical Council of NZ. A new generic National Referral Prioritization tool (NRPT) has been developed which includes a patient impact on life score. This study reports its trial implementation in orthopaedic surgery in a single centre. METHODS: Four months of referrals to the orthopaedic department were prioritized using the new NRPT and traditional clinical priority categories. Scores and acceptances were compared across conditions, surgeons and against the traditional categories. RESULTS: The mean NRPT was 60.1 (range 23-99). The correlation with impact on life was 0.59. There was good consistency of scores between surgeons. The NRPT score was significantly different across clinical priority categories (urgent, semi-urgent, routine). A total of 305 referrals (49%) were accepted using the NRPT compared with 493 (79%) if the traditional tool had been used. Patients with foot and ankle, carpal tunnel syndrome and upper limb conditions had the lowest scores and were more likely to be declined. CONCLUSIONS: The NRPT is the first tool designed to prioritize referral letters. It is more discriminating than the clinical priority categories used previously. It allows fine-tuning of a threshold score to balance acceptances and capacity.

Cemented or uncemented acetabular fixation in combination with the Exeter Universal cemented stem.

AIMS: To compare long-term survival of all-cemented and hybrid total hip arthroplasty (THA) using the Exeter Universal stem. METHODS: Details of 1,086 THAs performed between 1999 and 2005 using the Exeter stem and either a cemented (632) or uncemented acetabular component (454) were collected from local records and the New Zealand Joint Registry. A competing risks regression survival analysis was performed with death as the competing risk with adjustments made for age, sex, approach, and bearing. RESULTS: There were 61 revisions (9.7%; 0.82 revisions/100 observed component years, (OCYs)) in the all-cemented group and 18 (4.0%; 0.30/100 OCYs) in the hybrid group. The cumulative incidence of revision at 18 years was 12.1% for cemented and 5.2% for hybrids. There was a significantly greater risk of revision for all-cemented compared with hybrids (unadjusted sub-hazard ratio (SHR) 2.44; p = 0.001), and of revision for loosening, wear, or osteolysis (unadjusted SHR 3.77; p < 0.001). After adjustment, the increased risk of all-cause revision did not reach significance at age 70 years and above. The advantage for revision for loosening, wear, and osteolysis remained at all ages. CONCLUSION: This study supports the use of uncemented acetabular fixation when used in combination with the Exeter stem with improved survivorship for revision for aseptic loosening, wear, and osteolysis at all ages and for all-cause revision in patients less than 70 years. Cite this article: Bone Joint J 2020;102-B(4):414-422.

The Outcomes of Nonoperative Management of Patients With Hip and Knee Osteoarthritis Triaged to a Physiotherapy-Led Clinic at Minimum 5-Year Follow-Up and Factors Associated With Progression to Surgery.

BACKGROUND: The purpose of this study is to determine outcomes of a nonoperative treatment service for hip and knee osteoarthritis (OA), the "Joint Clinic," at minimum 5-year follow-up, and investigate factors that may influence progression to joint replacement surgery. METHODS: This is an observational cohort study of 337 patients with hip (n = 151, 45%) or knee OA (n = 186, 55%) seen at the Joint Clinic, at 5-7 years of follow-up. Kaplan-Meier survival curves were used to determine survivorship of the affected joint and Cox regression used to determine factors associated with time to surgery. RESULTS: At mean 6-year follow up, 188 (56%) patients had undergone or were awaiting total joint arthroplasty, 127 (38%) were still being managed nonoperatively, and 22 (7%) had died without having surgery. Patients with hip OA were more likely to have required surgery (111/151, 74%) than patients with knee OA (77/186, 41%) (chi-square = 33.6, P < .001). The 7-year surgery-free survival for hip OA was 23.7% and knee OA 55.9% (P < .001). Factors associated with increased likelihood of surgery were joint affected (hip, hazard ratio [HR] 2.80), Kellgren-Lawrence (KL) grade (KL 3, HR 2.02; KL 4, 4.79), and Oxford Hip/Knee Score (HR 1.34 for each 5 points worse at baseline). CONCLUSION: More than 50% of the patients referred to secondary care with mild-moderate knee OA may not need surgery at 7 years. Patients with hip OA and those with severe radiographic changes are more likely to require surgery and should not be delayed if there is not an adequate response to conservative measures.

Polyethylene liner dissociation with the Pinnacle acetabular component: should we be concerned?

Between 2007 and 2018, 535 total hip arthroplasties using the uncemented Pinnacle acetabular component (DePuy Synthes, Warsaw, IN) and polyethylene liner were implanted in our unit. Of these, 6 patients presented acutely with liner polyethylene dissociation, giving a rate of liner dissociation of 1.11%. All dissociations were atraumatic. Failure occurred at mean 37 months (range 4.5 to 130 months). Radiologically, all acetabular components were within safe zone of abduction and mean anteversion was 10 degrees (range 2-20). In one case, there was posterior impingement against the femoral neck due to femoral malalignment. All patients underwent head and liner exchange with no repeat failures. Despite excellent long-term results, the frequency of dissociated polyethylene liners is a cause of concern with the Pinnacle acetabular component.