Muscle weakness in hip osteoarthritis: A systematic review

One leg testing in hip and knee osteoarthritis: A comparison with a two-leg oriented functional outcome measure and self-reported functional measures

OBJECTIVE

To compare the responsiveness of two unilateral lower-limb performance-based tests, the one-leg rise test and the maximal step-up test, with the bilateral 30-second chair-stand test and the self-reported measure of physical function (HOOS/KOOS). Specific aims were to evaluate responsiveness, floor/ceiling effect and association between the instruments.

METHOD

Data was included from 111 participants, mean age 61.3 years (8.3), with clinically verified hip or knee osteoarthritis, who reported less than 150 minutes/week of moderate or vigorous intensity physical activity. Responsiveness, how well the instruments captured improvements, was measured as Cohen's standardised mean difference for effect size, and was assessed from baseline to 12 months following a physical activity intervention. Other assessments were floor and ceiling effects, and correlations between tests.

RESULTS

The maximal step-up test had an effect size of 0.57 (95% CI 0.37, 0.77), the 30-second chair-stand 0.48 (95% CI 0.29, 0.68) and the one-leg rise test 0.12 (95% CI 0.60, 0.31). The one-leg rise test had a floor effect as 72% of the participants scored zero at baseline and 63% at 12 months. The correlation between performance-based tests and questionnaires was considered to be minor (r = 0.188 to 0.226) (p = 0.018 to 0.048).

CONCLUSION

The unilateral maximal step-up test seems more responsive to change in physical function compared to the bilateral 30-second chair-stand test, although the tests did not differ statistically in effect size. The maximal step-up test provides specific information about each leg for the individual and allows for comparison between the legs.

Effect of an exercise intervention targeting hip strengthening in patients undergoing revision total hip replacement-A study protocol for a multicenter randomized controlled trial

BACKGROUND

Limited evidence exists regarding the effectiveness of pain relief and functional improvement in patients undergoing revision total hip replacement (THR). Furthermore, there are no clinical guidelines or consensus on optimal rehabilitation after revision THR.

PURPOSE

The primary aim of this study was to compare the effectiveness of an exercise intervention targeting hip strengthening with standard community-based rehabilitation in patients undergoing revision THR.

METHODS

This multicenter randomized controlled assessor-blinded trial will be conducted at eight hospitals and multiple municipality rehabilitation centers in Denmark. A total of 84 patients undergoing revision THR are estimated to be allocated to either an exercise intervention targeting hip strengthening (NEMEX-STR) or standard community-based rehabilitation (Usual care). Recruitment was initiated in November 2022 and is expected to be completed by June 2024. The primary outcome is change in functional performance measured by the 30 s chair stand test, from baseline to 4 months after the start of intervention. Secondary outcomes include hip disability and osteoarthritis outcome score; 40 m fast-paced walk test; 9-step timed stair climb test; leg extensor muscle power; global perceived effect; and adverse events. Other outcomes include The International Physical Activity Questionnaires, pain intensity, and European quality of life-5 dimensions. An intention-to-treat approach will be used for analyzing changes in primary and secondary outcome measures. The trial was approved by the Central Denmark Region Committees on Health Research Ethics (Journal No 1-10-72-134-22) and registered on the Central Denmark Regions' internal list of research projects (Journal No 1-16-02-285-22).

DISCUSSION

To our knowledge, this study is the first to explore different rehabilitation programs after revision THR through a randomized controlled trial. The results will provide clinically relevant evidence for optimal rehabilitation after revision THR for improving functional performance, physical function, and quality of life, with great importance for patients, relatives, physiotherapists, and decision-makers.

CLINICALTRIAL

GOV: NCT05657054.

Progressive Resistance Training or Neuromuscular Exercise for Hip Osteoarthritis : A Multicenter Cluster Randomized Controlled Trial

BACKGROUND

Exercise is recommended as first-line treatment for patients with hip osteoarthritis (OA). However, randomized controlled trials providing evidence for the optimal exercise type are lacking.

OBJECTIVE

To investigate whether progressive resistance training (PRT) is superior to neuromuscular exercise (NEMEX) for improving functional performance in patients with hip OA.

DESIGN

Multicenter, cluster-randomized, controlled, parallel-group, assessor-blinded, superiority trial. (ClinicalTrials.gov: NCT04714047).

SETTING

Hospitals and physiotherapy clinics.

PARTICIPANTS

160 participants with clinically diagnosed hip OA were enrolled from 18 January 2021 to 28 April 2023 and randomly assigned to PRT (n = 82) or NEMEX (n = 78).

INTERVENTION

Twelve weeks of PRT or NEMEX with 2 supervised 60-minute group sessions each week. The PRT intervention consisted of 5 high-intensity resistance training exercises targeting muscles at the hip and knee joints. The NEMEX intervention included 10 exercises and emphasized sensorimotor control and functional stability.

MEASUREMENTS

The primary outcome was change in the 30-second chair stand test (30s-CST). Key secondary outcomes were changes in scores on the pain and hip-related quality of life (QoL) subscales of the Hip Disability and Osteoarthritis Outcome Score (HOOS).

RESULTS

The mean changes from baseline to 12-week follow-up in the 30s-CST were 1.5 (95% CI, 0.9 to 2.1) chair stands with PRT and 1.5 (CI, 0.9 to 2.1) chair stands with NEMEX (difference, 0.0 [CI, -0.8 to 0.8] chair stands). For the HOOS pain subscale, mean changes were 8.6 (CI, 5.3 to 11.8) points with PRT and 9.3 (CI, 5.9 to 12.6) points with NEMEX (difference, -0.7 [CI, -5.3 to 4.0] points). For the HOOS QoL subscale, mean changes were 8.0 (CI, 4.3 to 11.7) points with PRT and 5.7 (CI, 1.9 to 9.5) points with NEMEX (difference, 2.3 [CI, -3.0 to 7.6] points).

LIMITATION

Participants and physiotherapists were not blinded.

CONCLUSION

In patients with hip OA, PRT is not superior to NEMEX for improving functional performance, hip pain, or hip-related QoL.

PRIMARY FUNDING SOURCE

Independent Research Fund Denmark.

Balancing act: Unraveling the link between muscle strength, proprioception, and stability in unilateral hip osteoarthritis

The objectives of this study are to compare hip muscle strength, hip joint proprioception, and functional balance between individuals with unilateral hip OA and asymptomatic individuals and to examine the relationships among these variables in the hip OA population. In a prospective cross-sectional study, 122 participants (unilateral Hip OA: n = 56, asymptomatic: n = 56) were assessed at the CAMS/KKU musculoskeletal Physical Therapy laboratory. Ethical standards were upheld throughout the research, with informed consent obtained. Hip muscle strength was measured using a hand-held dynamometer, hip joint proprioception with a digital inclinometer, and functional balance using the Berg Balance Scale (BBS) and Timed Up and Go (TUG) test. Hip OA individuals exhibited significantly lower muscle strength and proprioceptive accuracy, and poorer functional balance than controls (p < 0.003). Correlation analyses revealed a positive correlation between muscle strength and BBS scores (r = 0.38 to 0.42) and a negative correlation with TUG test times (r = -0.36 to -0.41). Hip joint reposition sense (JRS) in flexion showed a negative correlation with balance (r = -0.46), while JRS in abduction was positively correlated (r = 0.46). The study highlights the clinical importance of muscle strength and proprioception in functional balance among individuals with unilateral hip OA. The results support the incorporation of muscle strengthening and proprioceptive training in interventions to improve balance and mobility in this population.

Hybrid representation-enhanced sampling for Bayesian active learning in musculoskeletal segmentation of lower extremities

PURPOSE

Manual annotations for training deep learning models in auto-segmentation are time-intensive. This study introduces a hybrid representation-enhanced sampling strategy that integrates both density and diversity criteria within an uncertainty-based Bayesian active learning (BAL) framework to reduce annotation efforts by selecting the most informative training samples.

METHODS

The experiments are performed on two lower extremity datasets of MRI and CT images, focusing on the segmentation of the femur, pelvis, sacrum, quadriceps femoris, hamstrings, adductors, sartorius, and iliopsoas, utilizing a U-net-based BAL framework. Our method selects uncertain samples with high density and diversity for manual revision, optimizing for maximal similarity to unlabeled instances and minimal similarity to existing training data. We assess the accuracy and efficiency using dice and a proposed metric called reduced annotation cost (RAC), respectively. We further evaluate the impact of various acquisition rules on BAL performance and design an ablation study for effectiveness estimation.

RESULTS

In MRI and CT datasets, our method was superior or comparable to existing ones, achieving a 0.8% dice and 1.0% RAC increase in CT (statistically significant), and a 0.8% dice and 1.1% RAC increase in MRI (not statistically significant) in volume-wise acquisition. Our ablation study indicates that combining density and diversity criteria enhances the efficiency of BAL in musculoskeletal segmentation compared to using either criterion alone.

CONCLUSION

Our sampling method is proven efficient in reducing annotation costs in image segmentation tasks. The combination of the proposed method and our BAL framework provides a semi-automatic way for efficient annotation of medical image datasets.

'I saw it as a marriage-You can't have one without the other': A qualitative study of patient and physiotherapist experiences with a therapeutic combined strength and aerobic physical activity exercise programme for hip osteoarthritis

INTRODUCTION

To explore physiotherapist and patient experiences with, and acceptability of, a 12-week physiotherapist-guided combined strength and aerobic physical activity exercise programme for hip osteoarthritis (OA).

METHODS

A qualitative study using semi-structured interviews with 13 people with hip OA and four physiotherapists. Patients underwent a 12-week home exercise programme customised by weekly visits with one of the four physiotherapists. The programme aimed for patients to participate in 150 min of moderate-intensity aerobic physical activity, and 20-30 min of strengthening exercise 2-3 times per week in concordance with American College of Sports Medicine (ACSM) dosage guidelines. Following the programme, patients and physiotherapists participated in individual semi-structured interviews to explore the acceptability of the exercise programme and barriers and facilitators to participation. Data were audio-recorded, transcribed and analysed using a thematic approach.

RESULTS

Five over-arching themes (supporting subthemes) were identified from both patient and physiotherapist interviews: (i) positive outcomes (functional improvements, pain relief, empowerment through experience, commitment to continue); (ii) combined benefits of aerobic and strength exercises (complimentary effects, strengthening exercises key); (iii) valuing support from the physiotherapist (personalised care, skill performance feedback, coach effect, accountability); (iv) motivation and opportunity for exercise (positive symptom loop, integration into daily routine, prior exercise experience, Fitbit motivation); and (v) time-consuming commitment (physiotherapy visit frequency, travel inconvenience, time for exercise).

CONCLUSIONS

Experiences of participants in this study indicate that, although time-consuming, a combined aerobic physical activity and strengthening programme prescribed at ACSM dosage guidelines is acceptable and confers positive outcomes in individuals with hip OA.

Identifying Muscle Function-based Phenotypes Associated With Radiographic Progression of Secondary Hip Osteoarthritis

OBJECTIVE

The purposes of our study were to (1) identify muscle function-based clinical phenotypes in patients with hip osteoarthritis (OA) and (2) determine the association between those phenotypes and radiographic progression of hip OA.

DESIGN

Prospective cohort study.

SETTING

Clinical biomechanics laboratory of a university.

PARTICIPANTS

Fifty women patients with mild-to-moderate secondary hip OA (N=50) were recruited from the orthopedic department of a single institution.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Two-step cluster analyses were performed to classify the patients, using hip flexion, extension, abduction, and external/internal rotation muscle strength (cluster analysis 1); relative hip muscle strength to total hip strength (ie, hip muscle strength balance; cluster analysis 2); and both hip muscle strength and muscle strength balance (cluster analysis 3) as variables. The association between the phenotype and hip OA progression over 12 months (indicated by joint space width [JSW] >0.5 mm) was investigated by logistic regression analyses. Hip joint morphology, hip pain, gait speed, physical activity, Harris hip score, and SF-36 scores were compared between the phenotypes.

RESULTS

Radiographic progression of hip OA was observed in 42% of the patients. The patients were classified into 2 phenotypes in each of the 3 cluster analyses. The solution in cluster analyses 1 and 3 was similar, and high-function and low-function phenotypes were identified; however, no association was found between the phenotypes and hip OA progression. The phenotype 2-1 (high-risk phenotype) extracted in cluster analysis 2, which had relative muscle weakness in hip flexion and internal rotation, was associated with subsequent hip OA progression, even after adjusting for age and minimum JSW at baseline (adjusted odds ratio [95% confidence interval], 3.60 [1.07-12.05]; P=.039).

CONCLUSION

As preliminary findings, the phenotype based on hip muscle strength balance, rather than hip muscle strength, may be associated with hip OA progression.

Evaluation of Psoas Muscle Atrophy and the Degree of Fat Infiltration After Unilateral Hip Arthroplasty

OBJECTIVE

Atrophy of the muscles around the hip and thigh has been reported in patients with hip osteoarthritis (OA). Total hip arthroplasty (THA) reduces pain and improves quality of life and activity levels. Muscle strength of the hip and thigh also improves after THA. This study aimed to determine whether there is significant psoas muscle atrophy and to evaluate the degree of fat infiltration after unilateral hip arthroplasty.

SUBJECT AND METHODS

Patients who underwent unilateral total hip arthroplasty for primary hip osteoarthritis and who had lumbar vertebra magnetic resonance imaging (MRI) for any reason in the one-year preoperative and postoperative period were evaluated retrospectively. The degree of fat infiltration was also graded visually based on a modified Goutallier rating system.

RESULTS

The study was conducted with a total of 58 patients aged between 38 and 75, including 15 males and 43 females. Compared to the preoperative psoas muscle area values on the operated sides of the patients participating in the study, the decrease in the postoperative psoas muscle area was found to be statistically significant (p:0.000; p<0.05). Furthermore, the decrease in psoas muscle area on the non-operated side of the patients was also statistically significant (p:0.000; p<0.05). There was also a positive correlation between preoperative and postoperative psoas muscle areas (p:0.000; p<0.05).

CONCLUSION

Early identification of psoas muscle mass reduction may allow for a more proactive psoas strength improvement program to improve post-operative function and mobility.

Intra- and inter-rater reliability, agreement, and minimal detectable change of the handheld dynamometer in individuals with symptomatic hip osteoarthritis

INTRODUCTION

The handheld dynamometer has been validated to measure muscle strength in different muscle groups. However, to date, it has not been tested in individuals who experience pain induced by hip osteoarthritis. The current study aimed to evaluate the intra- and inter-rater reliability, agreement, and minimal detectable change of the Lafayette handheld dynamometer, model 1165, to assess the peak force (Pk) and average peak force (Af) of hip muscles in individuals with symptomatic hip osteoarthritis.

METHODS

Twenty participants with hip osteoarthritis (mean ± SD age: 58.7±15.3 years; body mass index: 28.8±4.2 kg/m2) and pain intensity on the Visual Analogue Scale ≥ 4 (8.05±1.2) were recruited to participate in this study. Pk and Af of hip flexors (seated position), abductors and adductors (supine position), and extensors (prone position) were collected in a single day by two independent raters, each one obtaining test and retest in randomly ordered separate sessions.

RESULTS

The intra-rater intraclass correlation coefficient (ICC) was classified as good (>0.75) or excellent (≥0.90) for all muscle groups and all inter-rater ICCs were classified as excellent. Rater A had a lower standard error of measurement compared to rater B, ranging from 0.15 to 0.58 kilogram-force (Kgf) compared with 0.34 to 1.25 kg, respectively. However, the inter-rater comparison showed a minimal detectable change (MDC) of < 10% for all Pk and Af measures for hip adductors and extensors. Finally, the inter-rater Bland-Altman analysis demonstrated good agreement for abductors, adductors, and extensors.

CONCLUSION

Despite pain and dysfunction related to hip osteoarthritis, the mean of two measures using a handheld dynamometer was shown to be a reliable tool to assess hip muscle strength, with good to excellent intra- and inter-rater ICCs, satisfactory agreement, and small values for MDC.

Does Sarcopenia Accompanying End-Stage Knee Osteoarthritis Affect the Outcomes following Total Knee Arthroplasty?

Background and Objectives: This study aimed to investigate the prevalence of sarcopenia in patients undergoing total knee arthroplasty (TKA) for advanced knee osteoarthritis (OA), and to assess whether sarcopenia accompanying OA affects patient-reported outcome measures (PROMs) after TKA. We evaluated which predisposing factors could influence the development of sarcopenia in patients with advanced knee OA. Material and Methods: A total of 445 patients whose body composition, muscle strength, and physical performance could be measured before primary TKA were enrolled. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 criteria. Patients were categorized into sarcopenia (S, n = 42) and non-sarcopenia groups (NS, n = 403). PROMs were investigated using the Knee Injury and Osteoarthritis Outcome Score and Western Ontario and McMaster Universities Osteoarthritis Index. Additionally, postoperative complications and predisposing factors for sarcopenia were evaluated. Results: The incidence of sarcopenia in the entire sample was 9.4%; the prevalence was higher in men (15.4%) than in women (8.7%), and significantly increased with advancing age (p < 0.001). At the six-month follow-up, PROMs in group S were significantly inferior to those in group NS, except for the pain score; however, at the 12-month follow-up, no significant difference was observed between the groups. Multivariate logistic regression indicated that age, body mass index (BMI), and a higher modified Charlson Comorbidity Index (mCCI) were predisposing factors for sarcopenia. Conclusions: A higher prevalence of sarcopenia was observed in men with progressive knee OA. Up to six months after primary TKA, PROMs in group S were inferior to those in group NS, except for the pain score; however, no significant difference was observed between the groups at 12 months. Age, BMI, and higher mCCI were predisposing factors for sarcopenia in patients with OA.

CycLing and EducATion (CLEAT): protocol for a single centre randomised controlled trial of a cycling and education intervention versus standard physiotherapy care for the treatment of hip osteoarthritis

BACKGROUND

Osteoarthritis (OA) is a chronic degenerative joint disorder for which there is no known cure. Non-surgical management for people with mild-to-moderate hip OA focuses mainly on alleviating pain and maximising function via the National Institute for Health and Care Excellence (NICE) recommended combination of education and advice, exercise, and, where appropriate, weight loss. The CHAIN (Cycling against Hip pAIN) intervention is a group cycling and education intervention conceived as a way of implementing the NICE guidance.

METHODS

CycLing and EducATion (CLEAT) is a pragmatic, two parallel arm, randomised controlled trial comparing CHAIN with standard physiotherapy care for the treatment of mild-to-moderate hip OA. We will recruit 256 participants referred to the local NHS physiotherapy department over a 24-month recruitment period. Participants diagnosed with hip OA according to NICE guidance and meeting the criteria for GP exercise referral will be eligible to participate. Primary outcome is the difference in Hip Disability and Osteoarthritis Outcome Score (HOOS) function, daily living subscale between those receiving CHAIN and standard physiotherapy care. Secondary outcomes include performance-based functional measures (40 m walking, 30s chair stand and stair climb tests), ability for patient to self-care (patient activation measure) and self-reported health-related resource use including primary and secondary care contacts. The primary economic endpoint is the number of quality adjusted life years (QALYs) at 24 weeks follow-up. The study is funded by the National Institute for Health Research, Research for Patient Benefit PB-PG-0816-20033.

DISCUSSION

The literature identifies a lack of high-quality trials which inform on the content and design of education and exercise in the treatment of patients with hip OA and explore cost-effectiveness. CLEAT is a pragmatic trial which seeks to build further evidence of the clinical benefits of the CHAIN intervention compared to standard physiotherapy care within a randomised, controlled trial setting, and examine its cost-effectiveness.

TRIAL REGISTRATION NUMBER

ISRCTN19778222. Protocol v4.1, 24th October 2022.

Smartphone videos of the sit-to-stand test predict osteoarthritis and health outcomes in a nationwide study

Physical function decline due to aging or disease can be assessed with quantitative motion analysis, but this currently requires expensive laboratory equipment. We introduce a self-guided quantitative motion analysis of the widely used five-repetition sit-to-stand test using a smartphone. Across 35 US states, 405 participants recorded a video performing the test in their homes. We found that the quantitative movement parameters extracted from the smartphone videos were related to a diagnosis of osteoarthritis, physical and mental health, body mass index, age, and ethnicity and race. Our findings demonstrate that at-home movement analysis goes beyond established clinical metrics to provide objective and inexpensive digital outcome metrics for nationwide studies.

Patient-Perceived Outcomes Improve Faster Than Hip Strength in Recovery After Surgical Correction for Symptomatic Femoroacetabular Impingement

Background: Patients with symptomatic femoroacetabular impingement (FAI) have hip strength deficits, instability, and increased risk for concomitant injury. While surgical intervention is an effective method of treatment for FAI, more information is needed about the recovery process. Purposes: We sought to understand how patients with FAI recover from surgical correction in the short term. Do patients' perceptions of improvement correspond with measured improvements in hip strength? Methods: We conducted a prospective cohort study of 17 patients (11 male, age range: 16-38 years) who were diagnosed with symptomatic FAI at a single surgeon's practice. Hip strength (flexion, extension, and abduction) was measured preoperatively and at 14, 26, and 52 weeks postoperatively. Patient-reported outcomes using the modified Harris Hip Score (mHHS) and Hip Outcome Osteoarthritis Score (HOOS) subscales were measured at the same time points and at 2 weeks postoperatively. Results: Compared with preoperative values, there was a significant increase in postoperative values at 26 and 52 weeks in normalized isokinetic hip extension (29% and 38%, respectively) and normalized hip abduction (48% and 55%, respectively). No differences in strength were observed at 14 weeks. Modified Harris Hip Score and all HOOS subscales were decreased by 2 weeks postoperatively, and by 14 weeks mHHS improved by 21%, and HOOS subscales improved as well (activities of daily living by 18%, pain by 34%, quality of life by 69%, sport and recreation by 36%, and symptoms by 28%). Conclusion: We observed that patient-reported outcomes including symptoms, function, and satisfaction improved at 14 weeks, while objective measures of hip strength improved at 26 weeks following surgical correction of FAI. More rigorous study is indicated.

A Cross-Sectional Study on Gluteal Muscles in Patients with Ankylosing Spondylitis at Different Stages of Hip Involvement

Hip involvement in ankylosing spondylitis (AS) is associated with severe functional impairment, and early diagnosis can improve the disease prognosis. We investigated gluteal muscle cross-sectional area (CSA) and radiodensity at different stages of hip involvement and their associations with AS-related clinical and laboratory parameters. This cross-sectional study included 83 patients with AS and 83 age- and sex-matched controls. Patients with AS were divided into three groups according to the Bath Ankylosing Spondylitis Radiology Hip Index system. The CSA and radiodensity of the gluteus maximus, medius, and minimus muscles were measured using computed tomography images. Muscle parameters were compared, and their relationships with clinical and laboratory parameters were evaluated. For the gluteus maximus, patients with AS had a lower CSA than controls, regardless of the degree of hip involvement. For the gluteus medius and minimus, patients with moderate/advanced hip involvement had significantly lower CSA and radiodensity than those with mild to no hip involvement. The severity of hip involvement was negatively associated with muscle parameters. CSA of the gluteus maximus decreased in early-stage hip involvement without any changes in radiographs, while radiodensity decreased in the later stages. Muscle parameters on computed tomography may be a more sensitive indicator than radiographic findings.

Artificial intelligence-based volumetric analysis of muscle atrophy and fatty degeneration in patients with hip osteoarthritis and its correlation with health-related quality of life

PURPOSE

Artificial intelligence (AI) technologies have enabled precise three-dimensional analysis of individual muscles on computed tomography (CT) or magnetic resonance images via automatic segmentation. This study aimed to perform three-dimensional assessments of pelvic and thigh muscle atrophy and fatty degeneration in patients with unilateral hip osteoarthritis using CT and to evaluate the correlation with health-related quality of life (HRQoL).

METHODS

The study included one man and 43 women. Six muscle groups were segmented, and the muscle atrophy ratio was calculated volumetrically. The degree of fatty degeneration was defined as the difference between the mean CT values (Hounsfield units [HU]) of the healthy and affected sides. HRQoL was evaluated using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index and the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ).

RESULTS

The mean muscle atrophy rate was 16.3%, and the mean degree of muscle fatty degeneration was 7.9 HU. Multivariate correlation analysis revealed that the WOMAC stiffness subscale was significantly related to fatty degeneration of the hamstrings, the WOMAC physical function subscale was significantly related to fatty degeneration of the iliopsoas muscle, and the JHEQ movement subscale was significantly related to fatty degeneration of the hip adductors.

CONCLUSION

We found that fatty degeneration of the hamstrings, iliopsoas, and hip adductor muscles was significantly related to HRQoL in patients with hip osteoarthritis. These findings suggest that these muscles should be targeted during conservative rehabilitation for HOA and perioperative rehabilitation for THA.

The relationship between muscle power, functional performance, accelerometer-based measurement of physical activity and patient-reported outcomes in patients with hip osteoarthritis: A cross-sectional study

BACKGROUND

Patients with unilateral hip osteoarthritis appear to have between-leg differences in leg extension power (LEP). The Nottingham Leg Extensor Power Rig provides reliable and valid results but requires sensitive equipment. It would be relevant to identify measures closely associated with this test.

OBJECTIVE

(i) To investigate if LEP is lower in the affected leg compared to the non-affected leg. Furthermore, to investigate the associations between LEP and the measures: (ii) Functional performance, (iii) accelerometer-based measurement of physical activity and (iv) patient-reported outcome measures (PROM).

DESIGN

Cross-sectional study including 60 patients (30 men, 30 women) with hip osteoarthritis scheduled for hip replacement.

METHOD

The counter movement jump and 10-m sprint tests were used to determine functional performance, accelerometer-sensors were used to determine physical activity and the Copenhagen Hip and Groin Outcome Score (HAGOS) was used to determine PROM.

RESULTS

(i) LEP in the affected leg corresponded to 79% [95% CI 74%; 85%] of the non-affected leg, (ii) LEP was positively associated with functional performance tests (β 0.63 to 0.78, p < 0.05), (iii) positively associated although non-significantly with physical activity (β 0.16 to 0.23, p > 0.05) and (iv) positively associated with the six HAGOS subscales (β 0.25 to 0.54, p < 0.05).

CONCLUSION

Functional performance tests may be used as feasible, inexpensive and fast ways to assess LEP in clinical settings. These results may suggest that interventions aimed at improving LEP can improve functional performance and PROM, but not physical activity. Future research is needed to confirm the causality of these cross-sectional findings.

THE CLINICAL TRIAL REGISTRATION NUMBERS

Danish Data Protection Agency (1-16-02-640-14), ClinicalTrials.gov (NTC02301182) and approved by the Danish Biomedical Research Ethics Committee (1-10-72- 343-14) prior to data collection.

Effects of a targeted resistance intervention compared to a sham intervention on gluteal muscle hypertrophy, fatty infiltration and strength in people with hip osteoarthritis: analysis of secondary outcomes from a randomised clinical trial

Background

People with hip osteoarthritis are typically offered a combination of education and exercise to address muscle atrophy and weakness. Limited evidence exists to assess the efficacy of exercise programs on muscle structure or function in this population. The aim of this study was to evaluate the effects of targeted resistance exercise on gluteal muscle hypertrophy and strength in people with mild-to-moderate hip osteoarthritis.

Methods

Twenty-seven participants with radiologically confirmed hip osteoarthritis recruited from a single site of a multi-site, double-blind clinical trial were randomly allocated to receive a 12-week targeted gluteal intervention or sham intervention. Magnetic resonance imaging and hand-held dynamometry were used to determine change in gluteal muscle volume, fatty infiltration and hip muscle strength. For gluteal muscle volume and strength outcomes mixed model analyses of variance (ANOVA) were conducted. A general linear model (ANOVA) analysis with fixed effects parameter estimates was used to assess the impact of sex on gluteal muscle size and strength of the affected limb only. For muscle fat index a mixed method ANOVA was used to assess the differences between groups and over time.

Results

In the targeted intervention group, gluteus minimus volume increased from baseline to post-intervention in both limbs (pooled mean difference: 0.06 cm³/kg, 95% confidence interval: 0.01 to 0.11) while no change occurred in the sham group (time x group effect: P = 0.025). Gluteus medius, gluteus maximus and tensor fascia lata volume did not change significantly over time. Hip strength (abduction, adduction, flexion, extension, external and internal rotation) improved similarly in both groups (time main effect: P ≤ 0.042). There was a consistent, albeit non-significant, pattern of reduced fatty infiltration after the targeted intervention.

Conclusion

Targeted resistance exercise resulted in gluteus minimus hypertrophy, but improvements in hip strength occurred in both groups. Clinicians delivering hip osteoarthritis rehabilitation programs might consider implementing a targeted exercise program to attenuate disease associated changes within gluteal muscles.

Trial registration

Australian New Zealand Clinical Trials Registry, ID: ACTRN12617000970347. Registered prospectively on 5 July 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05907-4.

Progressive resistance training compared to neuromuscular exercise in patients with hip osteoarthritis and the additive effect of exercise booster sessions: protocol for a multicentre cluster randomised controlled trial (The Hip Booster Trial)

INTRODUCTION

The primary aim of this randomised controlled trial is to investigate the effectiveness of 3 months of progressive resistance training (PRT) compared to neuromuscular exercise (NEMEX) on functional performance in patients with hip osteoarthritis (OA). Secondary aims are to investigate the effectiveness of exercise booster sessions (EBS) in prolonging the effects of the initial exercise interventions as well as to investigate the cost-effectiveness of PRT, NEMEX and EBS at 12-month follow-up.

METHODS AND ANALYSIS

This multicentre cluster randomised controlled trial will be conducted at hospitals and physiotherapy clinics across Denmark. A total of 160 participants with clinically diagnosed hip OA will be recruited. Participants will be cluster randomised to a 3-month intervention of either PRT or NEMEX and to receive EBS or not, resulting in four treatment arms.The primary outcome is change in functional performance, measured by the 30 s chair stand test at 3 months for the primary comparison and at 12 months for the EBS comparisons. Secondary outcomes include changes in 40 m fast-paced walk test, 9-step timed stair climb test, leg extensor muscle power and maximal strength, Hip disability and Osteoarthritis Outcome Score subscales, EuroQol Group 5-dimension, global perceived effect, physical activity and pain. Outcomes are measured at baseline, after the initial 3 months of intervention, and at 6-month, 9-month and 12-month follow-up. An intention-to-treat approach will be used for analysing changes in the primary and secondary outcome measures.

ETHICS AND DISSEMINATION

The trial has been approved by the Central Denmark Region Committee on Biomedical Research Ethics (Journal No 1-10-72-267-20) and registered at the Danish Data Protection Agency (Journal No 1-16-02-11-21). Results will be published in international peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT04714047.

Effects of Hip Bracing on Gait Biomechanics, Pain and Function in Subjects With Mild to Moderate Hip Osteoarthritis

Hip Osteoarthritis (HOA) is a common joint disease with serious impact on the quality of life of the affected persons. Additionally, persons with HOA often show alterations in gait biomechanics. Developing effective conservative treatment strategies is of paramount importance, as joint replacement is only indicated for end-stage HOA. In contrast to knee osteoarthritis, little is known about the effectiveness of hip bracing for the management of HOA. Studies analysing mechanically unloading hip braces partly showed beneficial results. However, methodological limitations of these studies, such as small sample sizes or lack of control groups, limit the applicability of the results. Additionally, mechanically unloading braces might impose restrictions on motion and comfort and thus, might not be suitable for people with only mild or moderate symptoms. The aim of this study was to comprehensively quantify the effects of unilateral HOA as well as functional hip bracing on gait biomechanics, pain, proprioception and functional capacity in people with mild to moderate HOA. Hip and pelvis biomechanics during walking were analysed in 21 subjects with mild to moderate HOA under three bracing conditions: unbraced, immediately after brace application and after 1 week of brace usage. Additionally, pain, hip proprioception and functional capacity were assessed. A matched group of 21 healthy subjects was included as reference. Kinematic and kinetic data were collected using a 16-camera infrared motion capturing system and two force plates. Visual analogue scales, an angle reproduction test and a 6-min walking test were applied to measure pain, hip proprioception and functional capacity, respectively. Subjects with HOA walked slower, with reduced step length, sagittal hip range of motion and peak extension angle and had a reduced functional capacity. After 1 week of brace application step length, walking speed and functional capacity were significantly increased. Additionally, pain perception was significantly lower in the intervention period. These results encourage the application of functional hip braces in the management of mild to moderate HOA. However, as key parameters of HOA gait such as a reduced peak extension angle remained unchanged, the underlying mechanisms remain partly unclear and have to be considered in the future.

Do femoral version abnormalities play a role in hip function of patients with hip pain?

BACKGROUND

A high prevalence of femoral version abnormalities has been observed in hip pain patients, with impact on hip range of motion and muscle strength that should be elucidated.

METHODS

Cross-sectional study. Thirty-one patients with hip pain (16 men and 15 female) were subjected to Biplanar X-Rays to quantify femoral version using three-dimensional measurements. The 62 hips were divided into normal version (10-20°, n = 18), anteverted (>20°, n = 19), and retroverted (<10°, n = 25). Joint range of motion for flexion, internal rotation, and external rotation was assessed through digital goniometry. Maximal isometric hip strength (flexion, extension, internal rotation, external rotation at 0° and 30°, abduction, adduction) was evaluated through hand-held dynamometry. Hip rotation index was calculated as external rotation minus internal rotation.

FINDINGS

Anteverted hips had greater internal rotation, while retroverted hips had greater external rotation (p = 0.001). Anteverted hips were weaker than retroverted hips for external rotation at 30° (p < 0.001), abduction (p = 0.006) and adduction (p < 0.001), and weaker than normal version hips for extension (p = 0.018). All three groups had different rotation index: retroverted>normal>anteverted (p < 0.001). The ordinal logistic regression found higher values of rotation index with higher probability of being retroverted (common odds ratio = 1.20). There was a strong correlation between femoral version group and rotation index (r_S = 0.76, p < 0.001). There was probability >70% of a hip being anteverted if the rotation index was <11°, and being retroverted if the index was >40°.

INTERPRETATION

Range of motion and muscle strength differed in hips with different femoral versions. The hip rotation index was a strong femoral version predictor.

Effects of adding aerobic physical activity to strengthening exercise on hip osteoarthritis symptoms: protocol for the PHOENIX randomised controlled trial

BACKGROUND

Hip osteoarthritis (OA) is a leading cause of musculoskeletal pain. Exercise is a core recommended treatment. Most evidence is based on muscle-strengthening exercise, but aerobic physical activity has potential to enhance clinical benefits. The primary aim of this study is to test the hypothesis that adding aerobic physical activity to a muscle strengthening exercise leads to significantly greater reduction in hip pain and improvements in physical function, compared to a lower-limb muscle strengthening exercise program alone at 3 months.

METHODS

This is a superiority, 2-group, parallel randomised controlled trial including 196 people with symptomatic hip OA from the community. Following baseline assessment, participants are randomly allocated to receive either i) aerobic physical activity and muscle strengthening exercise or; ii) muscle strengthening exercise only. Participants in both groups receive 9 consultations with a physiotherapist over 3 months. Both groups receive a progressive muscle strengthening exercise program in addition to advice about OA management. The aerobic physical activity plan includes a prescription of moderate intensity aerobic physical activity with a goal of attaining 150 min per week. Primary outcomes are self-reported hip pain assessed on an 11-point numeric rating scale (0 = 'no pain' and 10 = 'worst pain possible') and self-reported physical function (Western Ontario and McMaster Universities Osteoarthritis Index physical function subscale) at 3 months. Secondary outcomes include other measures of self-reported pain (assessed at 0, 3, 9 months), self-reported physical function (assessed at 0, 3, 9 months), performance-based physical function (assessed at 0, 3 months), joint stiffness (assessed at 0, 3, 9 months), quality of life (assessed at 0, 3, 9 months), muscle strength (assessed at 0, 3 months), and cardiorespiratory fitness (assessed at 0, 3 months). Other measures include adverse events, co-interventions, and adherence. Measures of body composition, serum inflammatory biomarkers, quantitative sensory measures, anxiety, depression, fear of movement and self-efficacy are included to explore causal mechanisms.

DISCUSSION

Findings will assist to provide an evidence-based recommendation regarding the additional effect of aerobic physical activity to lower-limb muscle strengthening on hip OA pain and physical function.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry reference: ACTRN 12619001297112. Registered 20th September 2019.

Effects of adding a diet intervention to exercise on hip osteoarthritis pain: protocol for the ECHO randomized controlled trial

Background

Hip osteoarthritis (OA) is a leading cause of musculoskeletal pain. Exercise is a core recommended treatment. Despite some clinical guidelines also recommending weight loss for hip OA, there is no evidence from randomised controlled trials (RCT) to substantiate these recommendations. This superiority, 2-group, parallel RCT will compare a combined diet and exercise program to an exercise only program, over 6 months.

Methods

One hundred people with symptomatic and radiographic hip OA will be recruited from the community. Following baseline assessment, participants will be randomly allocated to either, i) diet and exercise or; ii) exercise only. Participants in the diet and exercise group will have six consultations with a dietitian and five consultations with a physiotherapist via videoconferencing over 6 months. The exercise only group will have five consultations with a physiotherapist via videoconferencing over 6 months. The exercise program for both groups will include prescription of strengthening exercise and a physical activity plan, advice about OA management and additional educational resources. The diet intervention includes prescription of a ketogenic very low-calorie diet with meal replacements and educational resources to support weight loss and healthy eating. Primary outcome is self-reported hip pain via an 11-point numeric rating scale (0 = ‘no pain’ and 10 = ‘worst pain possible’) at 6 months. Secondary outcomes include self-reported body weight (at 0, 6 and 12 months) and body mass index (at 0, 6 and 12 months), visceral fat (measured using dual energy x-ray absorptiometry at 0 and 6 months), pain, physical function, quality of life (all measured using subscales of the Hip Osteoarthritis Outcome Scale at 0, 6 and 12 months), and change in pain and physical activity (measured using 7-point global rating of change Likert scale at 6 and 12 months). Additional measures include adherence, adverse events and cost-effectiveness.

Discussion

This study will determine whether a diet intervention in addition to exercise provides greater hip pain-relief, compared to exercise alone. Findings will assist clinicians in providing evidence-based advice regarding the effect of a dietary intervention on hip OA pain.

Trial registration

ClinicalTrials.gov . Identifier: NCT04825483. Registered 31st March 2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05128-9.

Hybrid Hyaluronic Acid versus High Molecular Weight Hyaluronic Acid for the Treatment of Hip Osteoarthritis in Overweight/Obese Patients

Background: Obesity is the main risk factor for hip osteoarthritis, negatively affecting the outcome of the disease. We evaluated the effectiveness of viscosupplementation with hybrid hyaluronic acid compared to that with high molecular weight hyaluronic acid in overweight/obese patients with hip osteoarthritis (OA). Methods: 80 patients were divided into two groups: a treatment group received two ultrasound-guided intra-articular hip injections of hybrid HA 15 days apart; a control group received a single ultrasound-guided infiltration with medium-high molecular weight hyaluronic acid (1500−2000 kDa). We assessed the pain, functional and cardiovascular capacity of the patients at baseline, after 3 months, and after 6 months of the infiltrative sessions. Results: The treatment group showed greater improvements in the scores on the NRS scale (5.4 ± 0.8 vs. 6.3 ± 0.8; p < 0.05) and in the Lequesne index (11.4 ± 2.6 vs. 13.6 ± 2.7; p < 0.05) and in the distance traveled at 6MWT (238.1 ± 53.9 m vs. 210.7 ± 46.2 m; p = 0.02) both at 3 months (T1) and at 6 months (T2). Conclusions: This study underlines the importance of exploiting the anti-inflammatory, analgesic, and chondrogenic properties of hybrid HA for the treatment of hip OA in overweight/obese patients.

The Impact of Pain on Functionality, Postural Control and Fall Risk in Woman Aged 45 to 64 Years Old

BACKGROUND

Ageing in women is associated with chronic degenerative pain leading to a functional decrease and therefore increase fall risk. It is therefore essential to detect early functional decreases in the presence of pain related to osteoarthritis.

OBJECTIVE

This cross-sectional study aimed to assess the impact of pain on functionality, postural control and fall risk in women aged between 45 to 64 years old.

METHODS

Twenty-one (21) women aged 45 to 64 were evaluated by clinical and functional measures such as a pain questionnaire (Lequesne Index), functional tests (Stair Step Test, 5 times sit-to-stand, 6MWD, Timed-up and Go) and postural performance (under force platform). Women were classified into 2 groups from the Lequesne Pain Index (PI): low pain (score ≤ 9) and strong pain (score ≥ 10) for subsequent comparisons on functionality (physical and postural control performance).

RESULTS

A significant impact was observed between the pain index (strong PI) and 3 of the 4 functional tests carried out including Stair Step Test (p = 0.001; g = 1.44), walking distance (p = 0.003; g = 1.31) and Timed-up and Go (p = 0.04; g = -0.93). The group with a strong PI score reported further poor postural control under force platform compared to the weak pain group.

CONCLUSION

Pain and severity based on the PI index negatively modulate physical and postural control performance in women aged 45 to 64 years old.

Proteomics profiling of human synovial fluid suggests increased protein interplay in early-osteoarthritis (OA) that is lost in late-stage OA

The underlying molecular mechanisms in osteoarthritis (OA) development are largely unknown. This study explores the proteome and the pairwise interplay of proteins in synovial fluid from patients with late-stage knee OA (arthroplasty), early knee OA (arthroscopy due to degenerative meniscal tear), and from deceased controls without knee OA. Synovial fluid samples were analyzed using state-of-the-art mass spectrometry with data-independent acquisition. The differential expression of the proteins detected was clustered and evaluated with data mining strategies and a multilevel model. Group-specific slopes of associations were estimated between expressions of each pair of identified proteins to assess the co-expression (i.e., interplay) between the proteins in each group. More proteins were increased in early-OA versus controls than late-stage OA versus controls. For most of these proteins, the fold changes between late-stage OA versus controls and early-stage OA versus controls were remarkably similar suggesting potential involvement in the OA process. Further, for the first time, this study illustrated distinct patterns in protein co-expression suggesting that the interplay between the protein machinery is increased in early-OA and lost in late-stage OA. Further efforts should focus on earlier stages of the disease than previously considered.

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Synovial fluid proteomics study of different stages of osteoarthritis (OA).

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Higher catabolic activity is found in both early- and late-stage OA.

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Imbalance of the metabolic homeostasis in late-stage OA.

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Understanding early-stage OA may lead to finding better effective therapies.

Efficacy of Exercise-Based Rehabilitation Programs for Improving Muscle Function and Size in People with Hip Osteoarthritis: A Systematic Review with Meta-Analysis

Objective: To determine the effect of exercise-based rehabilitation programs on hip and knee muscle function and size in people with hip osteoarthritis. Methods: Seven databases were systematically searched in order to identify studies that assessed muscle function (strength or power) and size in people with hip osteoarthritis after exercise-based rehabilitation programs. Studies were screened for eligibility and assessed for quality of evidence using the GRADE approach. Data were pooled, and meta-analyses was completed on 7 of the 11 included studies. Results: Six studies reported hip and/or knee function outcomes, and two reported muscle volumes that could be included in meta-analyses. Meta-analyses were conducted for four strength measures (hip abduction, hip extension, hip flexion, and knee extension) and muscle size (quadriceps femoris volume). For hip abduction, there was a low certainty of evidence with a small important effect (effect size = 0.28, 95% CI = 0.01, 0.54) favouring high-intensity resistance interventions compared to control. There were no other comparisons or overall meta-analyses that identified benefits for hip or knee muscle function or size. Conclusion: High-intensity resistance programs may increase hip abduction strength slightly when compared with a control group. No differences were identified in muscle function or size when comparing a high versus a low intensity group. It is unclear whether strength improvements identified in this review are associated with hypertrophy or other neuromuscular factors.

Automatic hip abductor muscle fat fraction estimation and association with early OA cartilage degeneration biomarkers

The aim of this study was to develop an automatic segmentation method for hip abductor muscles and find their fat fraction associations with early stage hip osteoarthritis (OA) cartilage degeneration biomarkers. This Institutional Review Board approved, Health Insurance Portability and Accountability Act compliant prospective study recruited 61 patients with evidence of hip OA or Femoroacetabular Impingement (FAI). Magnetic resonance (MR) images were acquired for cartilage segmentation, T_1ρ and T₂ relaxation times computation and grading of cartilage lesion scores. A 3D V-Net (Dice loss, Adam optimizer, learning rate = 1e^-4 , batch size = 3) was trained to segment the three muscles (gluteus medius, gluteus minimus, and tensor fascia latae). The V-Net performance was measured using Dice, distance maps between manual and automatic masks, and Bland-Altman plots of the fat fractions and volumes. Associations between muscle fat fraction and T_1ρ , T₂ relaxation times values were found using voxel based relaxometry (VBR). A p < 0.05 was considered significant. The V-Net had a Dice of 0.90, 0.88, and 0.91 (GMed, GMin, and TFL). The VBR results found associations of fat fraction of all three muscles in early stage OA and FAI patients with T_1ρ , T₂ relaxation times. Using an automatic, validated segmentation model, the associations derived between OA biomarkers and muscle fat fractions provide insight into early changes that occur in OA, and show that hip abductor muscle fat is associated with markers of cartilage degeneration.

Total hip arthroplasty versus progressive resistance training in patients with severe hip osteoarthritis: protocol for a multicentre, parallel-group, randomised controlled superiority trial

INTRODUCTION

Hip osteoarthritis (OA) is the leading cause for total hip arthroplasty (THA). Although, being considered as the surgery of the century up to 23% of the patients report long-term pain, and deficits in physical function and muscle strength may persist after THA. Progressive resistance training (PRT) appears to improve multiple outcomes moderately in patients with hip OA. Current treatment selection is based on low-level evidence as no randomised controlled trials have compared THA to non-surgical treatment. The primary aim of this trial is to investigate whether THA followed by standard care is superior to 12 weeks of supervised PRT followed by 12 weeks of optional unsupervised PRT for improving hip pain and function in patients with severe hip OA.

METHODS AND ANALYSIS

This is a protocol for a multicentre, parallel-group, assessor-blinded, randomised controlled superiority trial conducted at four hospitals across three healthcare regions in Denmark. 120 patients aged ≥50 years with clinical and radiographic hip OA found eligible for THA by an orthopaedic surgeon will be randomised to THA followed by standard care, or 12 weeks of PRT (allocation 1:1). The primary outcome will be change in patient-reported hip pain and function, measured using the Oxford Hip Score, from baseline to 6 months after initiating the treatment. Key secondary outcomes will be change in the Hip disability and Osteoarthritis Outcome Score subscales, University of California Los Angeles Activity Score, 40 m fast-paced walk test, 30 s chair stand test and occurrence of serious adverse events. Patients declining participation in the trial will be invited into a prospective observational cohort study.

ETHICS AND DISSEMINATION

The trial has been approved by The Regional Committees on Health Research Ethics for Southern Denmark (Project-ID: S-20180158). All results will be presented in peer-reviewed scientific journals and international conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT04070027).

A predictive model for hip abductor strength and knee extensor strength 12 months after total hip arthroplasty with an interaction term

Background

Identifying populations with poor muscle recovery after total hip arthroplasty (THA) is important for postoperative physical therapy. Preoperative muscle strength is a strong factor that determines postoperative muscle strength. However, this effect may depend on other factors. Thus, predictive models with interaction terms are important for accurately predicting postoperative muscle strength. This study aimed to develop a predictive model for lower muscle strength 12 months after THA which incorporates interaction terms.

Methods

Subjects were female patients with hip osteoarthritis who underwent unilateral THA. Patients with locomotor disorders, neurological disorders, or postoperative complications were excluded. Hip abductor and knee extensor strength were measured, and a generalized linear model approach with preoperative muscle strength, age, body weight, height, disease duration, physical activity, and leg extension as explanatory variables was used to identify factors that determine muscle strength 12 months after THA. Models with interaction terms between preoperative muscle strength and other explanatory variables were also examined.

Results

A total of 82 patients were analyzed. Preoperative muscle strength, age, body weight, physical activity, and disease duration were extracted as factors that significantly and independently determine hip abductor and knee extensor strength. The interaction term between preoperative muscle strength and age was identified as a factor that significantly determines knee extensor strength. Regression coefficients for preoperative knee extensor strength and postoperative muscle strength were significant when age was +1 SD, but not when age was -1 SD.

Conclusions

The predictive model demonstrated that lower muscle strength 12 months after THA is determined by preoperative muscle strength, age, weight, physical activity, disease duration, and preoperative muscle strength, with the effect of preoperative muscle strength on knee extensor strength being dependent on age. When predicting postoperative knee extensor strength using preoperative muscle strength, it is important to consider the effect of age.

Quantifying Muscle Forces and Joint Loading During Hip Exercises Performed With and Without an Elastic Resistance Band

An increase in hip joint contact forces (HJCFs) is one of the main contributing mechanical causes of hip joint pathologies, such as hip osteoarthritis, and its progression. The strengthening of the surrounding muscles of the joint is a way to increase joint stability, which results in the reduction of HJCF. Most of the exercise recommendations are based on expert opinions instead of evidence-based facts. This study aimed to quantify muscle forces and joint loading during rehabilitative exercises using an elastic resistance band (ERB). Hip exercise movements of 16 healthy volunteers were recorded using a three-dimensional motion capture system and two force plates. All exercises were performed without and with an ERB and two execution velocities. Hip joint kinematics, kinetics, muscle forces, and HJCF were calculated based on the musculoskeletal simulations in OpenSim. Time-normalized waveforms of the different exercise modalities were compared with each other and with reference values found during walking. The results showed that training with an ERB increases both target muscle forces and HJCF. Furthermore, the ERB reduced the hip joint range of motion during the exercises. The type of ERB used (soft vs. stiff ERB) and the execution velocity of the exercise had a minor impact on the peak muscle forces and HJCF. The velocity of exercise execution, however, had an influence on the total required muscle force. Performing hip exercises without an ERB resulted in similar or lower peak HJCF and lower muscle forces than those found during walking. Adding an ERB during hip exercises increased the peak muscle and HJCF but the values remained below those found during walking. Our workflow and findings can be used in conjunction with future studies to support exercise design.

Trunk movement compensation identified by inertial measurement units is associated with deficits in physical performance, muscle strength and functional capacity in people with hip osteoarthritis

BACKGROUND

Trunk movement compensation characterized as ipsilateral trunk lean and posterior rotation with respect to pelvis during stance phase of walking is common in people with hip osteoarthritis and a biomarker of deficits in physical function in older adults. However, the relationship between trunk movement compensation on deficits in physical performance, muscle strength and functional capacity is unknown.

METHODS

A cross-sectional study design was used. Two inertial measurement units were used to assess trunk movement compensation during the six-minute-walk-test. Knee extension, knee flexion and hip abduction strength were measured using hand-held dynamometer. Multivariate regression models, controlling for self-reported hip pain, were used to regress trunk movement compensation onto six-minute-walk-test and muscle strength measures. Pairwise t-tests were used to evaluate the difference trunk movement compensation has on functional capacity by comparing the first and last minute of the six-minute-walk-test.

FINDINGS

Thirty-five participants (63.3 ± 7.4 years, 57% male, 28.6 ± 4.5 kg/m²) were enrolled. Greater trunk movement compensation was related to poorer six-minute-walk-test (p = 0.03; r = -0.46). Greater hip abduction weakness was related to increased trunk movement compensation in both the sagittal (p = 0.05; r = -0.44) and frontal (p = 0.04; r = -0.38) planes. Participants demonstrated greater frontal plane trunk movement compensation during the last minute compared to the first minute of the six-minute-walk-test (p < 0.01).

INTERPRETATION

Trunk movement compensation, identified by inertial measure units, is a clinically relevant measure and has a moderate-to-strong relationship on deficits in physical performance, muscle strength and functional capacity. Inertial measurement units can be used as a practical means of measuring movement quality in the clinical setting.

Effects of step length and cadence on hip moment impulse in the frontal plane during the stance phase

Background

An excessive daily cumulative hip moment in the frontal plane (determined as the product of hip moment impulse in the frontal plane during the stance phase and mean number of steps per day) is a risk factor for the progression of hip osteoarthritis. Moreover, walking speed and step length decrease, whereas cadence increases in patients with hip osteoarthritis. However, the effects of step length and cadence on hip moment impulse in the frontal plane during the stance phase are not known. Therefore, this study aimed to examine the effects of step length and cadence on hip moment impulse in the frontal plane during the stance phase.

Methods

We used a public dataset (kinetic and kinematic data) of over-ground walking and selected 31 participants randomly from the full dataset of 57 participants. The selected participants walked at a self-selected speed and repeated the exercise 15 times. We analyzed the data for all 15 trials for each participant. Multiple regression analysis was performed with the hip moment impulse in the frontal plane during the stance phase as the dependent variable and step length and cadence as independent variables.

Results

The adjusted R² in this model was 0.71 (p < 0.001). The standardized partial regression coefficients of step length and cadence were 0.63 (t = 5.24; p < 0.001) and −0.60 (t =  − 4.58; p < 0.001), respectively.

Conclusions

Our results suggest that low cadence, not short step length, increases the hip moment impulse in the frontal plane. Our findings help understand the gait pattern with low hip moment impulse in the frontal plane.

Adherence to Neuromuscular Electrical Stimulation Interventions for Muscle Impairment in Hip and Knee Osteoarthritis: A Systematic Review

Background

Neuromuscular electrical stimulation (NMES) provides a promising approach to counteract muscle impairment in hip and knee osteoarthritis, and to expedite recovery from joint replacement surgery. Nonetheless, application into clinical orthopaedic practice remains limited, partly due to concerns regarding patient tolerance.

Objectives

This systematic review aimed to quantify levels of adherence to NMES interventions for muscle impairment in hip and knee osteoarthritis and identify strategies to increase compliance.

Data Sources

Randomised controlled trials (RCTs) were identified in a web-based literature review, completed in December 2020. The databases sourced included the Cochrane Library, CINAHL Complete, Medline Complete and PubMed.

Eligibility Criteria

Studies were included if they were: (i) conducted in cohorts of adults with hip or knee osteoarthritis; (ii) a protocol of electrical muscle stimulation prescribed to treat muscle impairment; and (iii) reported intervention adherence or attrition rate. Data were extracted on adherence rate, reasons for non-adherence and potential strategies to increase adherence. Risk of bias was assessed using the Physiotherapy Evidence Database (PEDro) scale.

Results

The search yielded 120 articles, of which 15 studies were considered eligible and included in the analysis (n = 922). All NMES treatment was applied to the quadriceps, with 1 study targeting the quadriceps and calves. The mean PEDRO score of the included studies was 6.80 out of a possible 10 (range 6-8). Mean adherence did not differ between groups receiving treatment with NMES (85% ± 12%) and control groups receiving voluntary exercise or education (84% ± 9%) (P = .97). Reasons for non-adherence or attrition included a dislike of the device, dizziness, pain and discomfort. Strategies to increase adherence included NMES education, a familiarisation period, supervision, setting thresholds based upon patient tolerance, monitoring pain levels during stimulation and using built-in adherence trackers.

Conclusions

This systematic review indicates that adherence to NMES interventions for muscle impairment in hip and knee osteoarthritis in clinical trials does not differ to control groups receiving education or voluntary exercise, and hence should not be a barrier to application in clinical practice.

Comparison of gluteus medius strength between individuals with obesity and normal-weight individuals: a cross-sectional study

Background

The hip abductor muscles, primarily the gluteus medius, play an important role in stabilizing the pelvis during gait. Gluteus medius weakness is associated with biomechanical changes and musculoskeletal disorders. Individuals with obesity can have great difficulty maintaining abductor muscular function due to being overweight and possibly experiencing a decrease in muscle mass. However, it is still unclear whether the musculature of person with obesity can compensate for these changes. Therefore, the aim of this study was to compare gluteus medius strength between individuals with obesity and normal-weight individuals using a digital hand-held dynamometer.

Methods

Twenty-five participants with obesity (BMI > 35 kg/m²) were matched for sex, age, and height with normal-weight individuals. Gluteus medius strength was measured by a single examiner using a belt-stabilized hand-held digital dynamometer placed on the knee of the individuals positioned in lateral decubitus. Three measurements were recorded with rest intervals, and only the highest value measured for each limb was used for analysis. The differences between pairs were calculated, and the normality of the data was assessed using the Shapiro-Wilk test (p < 0.05). The matrices of the variables were standardized and analysed using principal component analysis (PCA).

Results

For the strength variables (Newtons) on both sides, no significant differences were detected between the groups (p > 0.05). However, significant differences were detected in these variables between the groups (p < 0.05) when the measurements were normalized to body weight (Newtons/kilograms). PCA indicated that both the absolute and normalized values of strength are lower in participants with obesity than in normal-weight.

Conclusions

These findings suggest that people with obesity could have the same or less strength (PCA) to move more mass, which may imply a relative weakness that induces functional limitations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04470-8.

Strength and endurance deficits in adults with moderate-to-severe hip osteoarthritis, compared to healthy, older adults

PURPOSE

This study compares lower limb muscle strength and endurance in adults with hip osteoarthritis, to an age-matched control group.

METHODS

Thirteen adults with moderate-to-severe hip osteoarthritis (as graded by the Oxford Hip Score) and fifteen older adults participated. Maximal voluntary isometric contraction of the knee extensors, knee flexors and hip abductors and isotonic endurance of the knee extensors were measured using a dynamometer. Function was assessed using the 30-second chair stand test, the 40 m fast-paced walk test and a stair negotiation test. Data were compared between groups using t-tests.

RESULTS

Participants with hip osteoarthritis demonstrated weakness in the affected limb when compared to the control limb during knee flexion (34%, p = 0.004) and hip abduction (46%, p = 0.001). Weakness was also observed in the contralateral knee flexors (31%, p = 0.01). When compared to the control limb, the knee extensors of the hip osteoarthritis group were exhausted prematurely in the affected (70%, p = 0.001) and contralateral limb (62%, p = 0.005). The hip osteoarthritis group took twice as long to stair climb (p = 0.002), walked 40% slower, (p < 0.001), and had a 35% lower sit-stand performance (p < 0.001).

CONCLUSIONS

Moderate-to-severe hip osteoarthritis may be characterised by bilateral deficits in lower-limb maximal strength, markedly lower knee extensor endurance and impaired functional performance.Implications for rehabilitationIn addition to bilateral deficits in maximal strength of the hip and knee muscles, moderate-to-severe hip osteoarthritis may be characterised by markedly lower muscular endurance of the knee extensors and impaired functional performance.The endurance capacity of the knee extensors can play an important role in daily function, and thus it is important to consider endurance training principles when prescribing exercise for this patient group.Research studies evaluating exercise programmes underpinned by endurance training principles are required to understand the benefits to patients with hip osteoarthritis, and to inform specific exercise prescription in clinical practice.

Exercise in patients with hip osteoarthritis - effects on muscle and functional performance: A randomized trial

Background: It is believed that clinical management of osteoarthritis should address muscle weakness to improve physical function and prevent disability and frailty.Objectives: This sub-study investigated the effects of supervised progressive resistance training (RT), supervised Nordic Walking (NW), and unsupervised home-based exercise (HBE) on muscle and functional performance; and associations between these exercise-induced changes in persons with hip osteoarthritis.Methods: Forty-two patients with hip osteoarthritis were recruited from a larger RCT (NCT01387867). All the groups (RT, n = 15; NW, n = 12; HBE, n = 15) exercised 1 h 3 times/week for 4 months. Quadriceps cross-sectional area (QCSA, MRI-determined); quadriceps strength (QMVC); leg extensor power (LEP); functional performance (chair stands (30sCS); stair climbs (TSC); and 6-minute walk (6MWT)) were assessed at baseline and 4 months.Results: Per protocol analyses (one-way ANOVA and Bonferroni test) showed significant between-group differences for improvements in QCSA in the most symptomatic leg favoring RT versus NW (2.3 cm², 95% CI [0.6, 3.9]) and HBE (2.3 cm² [0.8, 3.9]); and 30sCS (1.8 repetitions [0.2-3.3]), and 6MWT (35.1 m [3.5-66.7]) favoring NW versus HBE. Associations existed between exercise-induced changes in QCSA and QMVC (r = 0.366, p = .019) for the most symptomatic leg and between changes in 6MWT and QMVC (r = 0.320, p = .04) and LEP (r = 0.381, p = .01), respectively, for the least symptomatic leg.Conclusions: Resistance training appeared effective for improving muscle mass, but less effective for improving muscle strength, power, and functional performance. Only exercise-induced changes in muscle strength and power of the least symptomatic leg, not the most symptomatic leg, were related to changes in functional performance.

Individuals with Unilateral Mild-to-Moderate Hip Osteoarthritis Exhibit Lower Limb Kinematic Asymmetry during Walking But Not Sit-to-Stand

Asymmetry during gait is associated with the evolution of secondary osteoarthritis. Kinematic asymmetry has been reported in advanced stages of hip osteoarthritis but has not been evaluated in earlier stages of the disease or has it been directly compared with unilateral and bilateral hip osteoarthritis. Our objective was to evaluate within-group symmetry and compare between-group asymmetry for three-dimensional pelvis, hip, knee, and ankle kinematics during walking and sit-to-stand in individuals with unilateral mild-to-moderate hip OA, bilateral mild-to-moderate hip osteoarthritis, and healthy controls. Twelve individuals with unilateral mild-to-moderate hip OA, nine individuals with bilateral mild-to-moderate symptomatic and radiographic hip OA, and 21 age-comparable healthy controls underwent three-dimensional motion analysis during walking and sit-to-stand. Pelvis and lower limb joint angles were calculated using inverse kinematics and between-limb symmetry was assessed for each group. Any resulting asymmetries (most affected minus contralateral limb) were compared between groups. Participants with unilateral hip osteoarthritis exhibited significantly less hip extension (7.90°), knee flexion (4.72°), and anterior pelvic tilt (3.38°) on their affected limb compared with the contralateral limb during the stance phase of walking. Those with unilateral hip osteoarthritis were significantly more asymmetrical than controls for sagittal plane hip and pelvis angles. No significant asymmetries were detected within- or between-groups for sit-to-stand. Individuals with unilateral hip osteoarthritis exhibited lower limb asymmetries consistent with those reported in advanced stages of disease during walking, but not sit-to-stand. Consideration of the possible negative effects of gait asymmetry on the health of the affected and other compensating joints appears warranted in the management of hip OA.

Geometrical restoration during total hip arthroplasty is related to change in gait pattern - a study based on computed tomography and three-dimensional gait analysis

Background

The effect of change in hip anatomy on change in gait pattern is not well described in current literature. Therefore, our primary aim was to describe and quantify changes in hip geometry and gait pattern 1 year after total hip arthroplasty (THA) in individuals with hip osteoarthritis. Our secondary aim was to explore the effect of postoperative change in femoral neck anteversion (FNA) and femoral offset and acetabular offset (FO/AO) quota on postoperative change in hip rotation and hip adduction moment during gait, respectively, 1 year after THA”.

Methods

Sixty-five individuals with primary hip osteoarthritis, scheduled for THA, were analyzed in this prospective intervention study. Participants were evaluated pre- and 1 year postoperatively with computed tomography-scans, three-dimensional gait analysis, and patient-reported outcome measures. Multiple linear regressions were performed to evaluate the association between change in joint anatomy and change in gait pattern after THA.

Results

One year postoperatively, global offset was symmetrical between sides as a result of decreased acetabular offset and increased femoral offset on the operated side. Quality of overall gait pattern improved, and participants walked faster and with less trunk lean over the affected side. FNA and hip rotations during walking changed equally in external and internal directions after THA and change in hip rotation during walking was associated with change in FNA in the same direction. An increase in external hip adduction moments was, on the other hand, not associated with change in FO/AO quota but with a more upright walking position and increased walking speed.

Conclusions

The findings of this study suggest that geometrical restoration during THA impacts postoperative gait pattern and, in addition to known factors such as FO, height of hip rotation center, and leg length discrepancy, the FNA must also be taken into consideration.

Trial registration

Trial registration: Clinicaltrial.gov, NCT01512550, Registered 19 January 2012 - Retrospectively registered.

Exercise as Medicine During the Course of Hip Osteoarthritis

Exercise is now considered medicine in numerous chronic conditions and is essentially without side effects. We hypothesize that exercise is primary, secondary, and tertiary prevention at different stages of hip osteoarthritis (preclinical, mild-moderate, and severe hip osteoarthritis) and after total hip arthroplasty.

Walking energetics and abductor strength are associated with physical activity in older women with hip osteoarthritis

BACKGROUND

Osteoarthritis (OA) can hinder physical activity in older adults for reasons that are not fully understood. Functional barriers may exist such as reduced muscle strength around the affected joint, potentially affecting physical activity. Aging-associated declines in energy capacity may also be exacerbated by OA. These factors may work together to influence physical activity in people with OA.

RESEARCH QUESTION

Our objective was to evaluate the combined role of walking energetics and hip abductor strength on physical activity in older women with hip OA.

METHODS

We evaluated 30 women with moderately symptomatic hip OA (61 ± 10 yrs; 30.7 ± 4.9 kg/m²) in this cross-sectional observational study. We measured physical activity using the UCLA activity score and quantified activity frequency and intensity using accelerometers worn for seven days (7 ± 2 days). We used a portable oxygen exchange system to measure energy used during walking at preferred speeds (relative to total energy capacity assessed using a six-minute walk test) and a dynamometer to measure hip abductor strength. We used Pearson correlations and regression analysis to test our hypotheses.

RESULTS

Greater energy used during walking was associated with lower self-reported physical activity (R=-0.626, p < 0.001), more sedentary time (R = 0.567, p = 0.002), and less light activity time (R=-0.644, p < 0.001). Lower hip abductor strength was associated with lower self-reported physical activity (R = 0.406, p = 0.039). While there was no association between hip abductor strength and energy used during walking, together these variables predicted 55.5 % of the variance in self-reported physical activity.

SIGNIFICANCE

Results suggest intervention targets to promote physical activity in this population.

Disentangling Associations Between Serum Muscle Biomarkers and Sarcopenia in the Presence of Pain and Inflammation Among Patients With Osteoarthritis: The SPSS-OK Study

BACKGROUND/OBJECTIVE

Reduction of muscle markers, such as creatine phosphokinase (CK), in rheumatic diseases and its association with reduced muscle mass may be of clinical importance in osteoarthritis (OA). Considering the complexity of secondary sarcopenia, clarifying the association between muscle markers and sarcopenia and disentangling the involvement of OA-related conditions are of clinical importance. We investigated the association between serum muscle biomarkers and sarcopenia among patients with OA, considering the presence of pain and inflammation.

METHODS

Overall, 1425 patients with knee and hip OA scheduled for joint replacement surgery were included in a single-center cross-sectional study from Screening for People Suffering Sarcopenia in Orthopedic cohort of Kobe study. Primary outcome was sarcopenia defined by 2 criteria (the Asian Working Group for Sarcopenia and the European Working Group on Sarcopenia in Older People). Pain and inflammation were measured using the numeric rating scale and serum C-reactive protein (CRP) levels, respectively. Associations between the biomarkers (serum CK, aspartate aminotransferase, alanine aminotransferase) and sarcopenia were examined using logistic regression models.

RESULTS

Sarcopenia by the Asian Working Group for Sarcopenia criteria was present in 4.0% of patients. In adjusted analyses, sarcopenia was negatively associated with higher serum CK levels, but not with serum aspartate aminotransferase or alanine aminotransferase levels independent of pain score and serum CRP. Neither pain score nor serum CRP level was associated with sarcopenia. Similar results were found when the European Working Group on Sarcopenia in Older People criteria were used.

CONCLUSIONS

Serum CK was associated with sarcopenia, suggesting the potential usefulness for sarcopenia detection regardless of pain or inflammation in OA.

Effectiveness of Dry Needling Therapy on Pain, Hip Muscle Strength, and Physical Function in Patients With Hip Osteoarthritis: A Randomized Controlled Trial

OBJECTIVE

To investigate the short-term effects of dry needling (DN) on physical function, pain, and hip muscle strength in patients with hip osteoarthritis (OA).

DESIGN

A double-blind, placebo-control, randomized controlled trial.

SETTING

Private practice physiotherapy clinic.

PARTICIPANTS

Patients with unilateral hip OA (N=45) were randomly allocated to a DN group, sham DN group, or control group.

INTERVENTIONS

Patients in the DN and sham groups received 3 treatment sessions. Three active myofascial trigger points (MTrPs) were treated in each session with DN or a sham needle procedure. The treatment was applied in active MTrPs of the iliopsoas, rectus femoris, tensor fasciae latae, and gluteus minimus muscles.

MAIN OUTCOME MEASURES

Physical function was assessed with the Western Ontario and McMaster Universities (WOMAC) physical function subscale, the timed Up and Go test, and the 40-meter self-paced walk test. Intensity of hip pain related to physical function was evaluated using the visual analog scale and WOMAC pain subscale. The maximal isometric force of hip muscles was recorded with a handheld dynamometer.

RESULTS

Significant group by time interactions were shown for physical function, pain, and hip muscle force variables. Post hoc tests revealed a significant reduction in hip pain and significant improvements in physical function and hip muscle strength in the DN group compared with the sham and control groups. The DN group showed within- and between-groups large effect sizes (d>0.8).

CONCLUSIONS

DN therapy in active MTrPs of the hip muscles reduced pain and improved hip muscle strength and physical function in patients with hip OA. DN in active MTrPs of the hip muscles should be considered for the management of hip OA.

Gluteal atrophy and fatty infiltration in end-stage osteoarthritis of the hip: a case-control study

Aims

The gluteus minimus (GMin) and gluteus medius (GMed) have unique structural and functional segments that may be affected to varying degrees, by end-stage osteoarthritis (OA) and normal ageing. We used data from patients with end-stage OA and matched healthy controls to 1) quantify the atrophy of the GMin and GMed in the two groups and 2) describe the distinct patterns of the fatty infiltration in the different segments of the GMin and GMed in the two groups.

Methods

A total of 39 patients with end-stage OA and 12 age- and sex frequency-matched healthy controls were prospectively enrolled in the study. Fatty infiltration within the different segments of the GMin and the GMed was assessed on MRI according to the semiquantitative classification system of Goutallier and normalized cross-sectional areas were measured.

Results

The GMin was smaller in the OA-group (p < 0.001) compared to the control group, but there was no group difference in the size of the GMed (p = 0.101). Higher levels of fatty infiltration were identified in the anterior segment of the GMin (p = 0.006) and the anterior (p = 0.006) and middle (p = 0.047) segments of the GMed in the OA group. All subjects in the control group had fatty infiltration of the anterior segment of the GMin, but all except one had no fatty infiltration in the entire GMed.

Conclusion

End-stage OA was associated with significant atrophy of the GMin and higher levels of fatty infiltration, particularly in the anterior segments of the GMin and GMed. Minor fatty infiltration of the anterior segment of GMin appears to be a normal part of ageing. Our study has demonstrated different patterns of atrophy and fatty infiltration between patients with end-stage OA and healthy matched peers.

Cite this article: Bone Jt Open 2021;2(1):40–47.

End-stage knee osteoarthritis with and without sarcopenia and the effect of knee arthroplasty - a prospective cohort study

Background

Sarcopenia often accompanies osteoarthritis (OA), which is managed by total knee arthroplasty (TKA) in the late stage. Recent studies have suggested a higher risk of post-operative complications after TKA in sarcopenic OA subjects, but whether TKA can benefit them similar to non-sarcopenic subjects remains unexplored. This study aimed to examine the dynamic, mutual impact of sarcopenia and TKA in a one-year post-operative period.

Methods

This prospective cohort study was conducted between 2015 to 2018 at our hospital. Patients with end-stage OA of the knee waiting for TKA were recruited into the study. Primary outcome measures were change in muscle strength, mass and function. Secondary outcome measures were quality of life (QOL) measurements for pain, psychological and physical health.

Results

Fifty-eight patients were recruited, of which 79.3% were female and 32.8% already had sarcopenia at baseline. The average age of sarcopenic subjects and non-sarcopenic subjects was comparable (67.89 ± 7.07 vs. 67.92 ± 6.85; p = 0.99), but sarcopenic subjects had a lower body mass index (BMI) (25.64 ± 2.64 vs. 28.57 ± 4.04; p = 0.01). There was a statistically significant improvement in walking speed (10.24 ± 5.35 vs. 7.69 ± 2.68, p < 0.01) and muscle strength in both sarcopenic and non-sarcopenic patients after TKA. This was accompanied by an improvement trend in muscle mass in all subjects. There was no change in handgrip power before and after TKA and subsequent follow-up (19.31 ± 5.92 vs. 18.98 ± 6.37 vs. 19.36 ± 7.66; p = 0.97). QOL measured before, after and at follow-up with WOMAC (total: 42.27 ± 15.98 vs. 20.65 ± 15.24 vs. 16.65 ± 18.13) and SF12v2 (PCS: 33.06 ± 8.55 vs. 38.96 ± 8.01 vs. 40.67 ± 7.93) revealed progressive significant improvement (both comparisons p ≤ 0.01). Further analysis with the IPAQ also found increased engagement of high-intensity activities.

Conclusions

This study showed that sarcopenia among patients with end-stage OA of the knee is not uncommon, but both sarcopenic and non-sarcopenic OA patients achieved significant clinical and functional improvement after TKA. Further studies with a larger sample size and different ethnicities could help ascertain a beneficial role of TKA in sarcopenic OA subjects.

Trial registration

Registry: ClinicalTrials.gov, Registration number: NCT03579329. Date of registration: 6 July 2018. Retrospectively registered.

Lab-based feasibility and acceptability of neuromuscular electrical stimulation in hip osteoarthritis rehabilitation

INTRODUCTION

Neuromuscular electrical stimulation (NMES) could provide an alternative or adjunct treatment modality to induce muscle hypertrophy in the hip osteoarthritis population. This preliminary study evaluates the feasibility and acceptability of NMES to evoke involuntary muscle contractions in adults with advanced hip osteoarthritis.

METHODS

Thirteen adults with moderate-to-severe hip osteoarthritis and fifteen healthy, older adults were invited to a lab-based testing session. NMES was applied unilaterally to the knee extensors and hip abductors for one continuous, five-minute testing session. Data were collected on device acceptability, tolerability and muscle contractile force, and compared between groups.

RESULTS

Electrical stimulation of the knee extensors elicited a visible muscular contraction in 11 participants (85%) with hip osteoarthritis and 15 controls (100%) at an intensity acceptable to the participant. Electrical stimulation of the hip abductors elicited a muscular contraction in eight participants (62%) with osteoarthritis, and ten controls (67%). Muscle contractile force, pain, discomfort and acceptability did not differ between groups, however NMES of the knee extensors was favoured across all measures of assessment when compared to the hip abductors.

CONCLUSIONS

Electrical stimulation of the knee extensors may be a feasible and acceptable treatment modality to address muscle atrophy in adults with advanced hip osteoarthritis.

Hypergravity as a gravitational therapy mitigates the effects of knee osteoarthritis on the musculoskeletal system in a murine model

Insights into the effects of osteoarthritis (OA) and physical interventions on the musculoskeletal system are limited. Our goal was to analyze musculoskeletal changes in OA mice and test the efficacy of 8-week exposure to hypergravity, as a replacement of physical activity. 16-week-old male (C57BL/6J) mice allocated to sham control and OA groups not centrifuged (Ctrl 1g and OA 1g, respectively) or centrifuged at 2g acceleration (Ctrl 2g and OA 2g). OA 1g displayed decreased trabecular bone in the proximal tibia metaphysis and increased osteoclastic activity and local TNFα gene expression, all entirely prevented by 2g gravitational therapy. However, while cortical bone of tibia midshaft was preserved in OA 1g (vs. ctrl), it is thinner in OA 2g (vs. OA 1g). In the hind limb, OA at 1g increased fibers with lipid droplets by 48% in the tibialis anterior, a fact fully prevented by 2g. In Ctrl, 2g increased soleus, tibialis anterior and gastrocnemius masses. In the soleus of both Ctrl and OA, 2g induced larger fibers and a switch from type-II to type-I fiber. Catabolic (myostatin and its receptor activin RIIb and visfatine) and anabolic (FNDC5) genes dramatically increased in Ctrl 2g and OA 2g (p<0.01 vs 1g). Nevertheless, the overexpression of FNDC5 (and follistatine) was smaller in OA 2g than in Ctrl 2g. Thus, hypergravity in OA mice produced positive effects for trabecular bone and muscle typology, similar to resistance exercises, but negative effects for cortical bone.

A Systematic Review of the Associations Between Inverse Dynamics and Musculoskeletal Modeling to Investigate Joint Loading in a Clinical Environment

The assessment of knee or hip joint loading by external joint moments is mainly used to draw conclusions on clinical decision making. However, the correlation between internal and external loads has not been systematically analyzed. This systematic review aims, therefore, to clarify the relationship between external and internal joint loading measures during gait. A systematic database search was performed to identify appropriate studies for inclusion. In total, 4,554 articles were identified, while 17 articles were finally included in data extraction. External joint loading parameters were calculated using the inverse dynamics approach and internal joint loading parameters by musculoskeletal modeling or instrumented prosthesis. It was found that the medial and total knee joint contact forces as well as hip joint contact forces in the first half of stance can be well predicted using external joint moments in the frontal plane, which is further improved by including the sagittal joint moment. Worse correlations were found for the peak in the second half of stance as well as for internal lateral knee joint contact forces. The estimation of external joint moments is useful for a general statement about the peak in the first half of stance or for the maximal loading. Nevertheless, when investigating diseases as valgus malalignment, the estimation of lateral knee joint contact forces is necessary for clinical decision making because external joint moments could not predict the lateral knee joint loading sufficient enough. Dependent on the clinical question, either estimating the external joint moments by inverse dynamics or internal joint contact forces by musculoskeletal modeling should be used.

Psoas muscle atrophy following unilateral hip arthroplasty

BACKGROUND

Studies have demonstrated the presence of muscle atrophy around the hip in patients with hip osteoarthritis. Few studies have examined the psoas muscle or assessed it at a paraspinal level in patients post-total hip arthroplasty. The aim of this study was to determine if there is significant psoas muscle atrophy as indicated by muscle cross-sectional area and high degree of fat infiltration post-unilateral hip arthroplasty.

METHODS

Retrospective analysis of 341 patients with unilateral hip implant and subsequent lumbar spine MRI over a 8-year period was performed. Fat infiltration and cross-sectional area of the psoas muscle at L3/4 level were measured by two musculoskeletal fellows (1 year experience in musculoskeletal radiology), and comparison made between the implant and non-operative sides was made. Fat infiltration was measured using the modified Goutallier grading. The degree of hip osteoarthritis in the non-operative side was measured using the Kellgren-Lawrence grading. The data was analysed using paired t test, ANOVA, unpaired t test, Pearson correlation and Jonckheere-Terpstra test.

RESULTS

The cross-sectional area of the psoas muscle on the implant side was significantly less than the non-operative side. There was significance between the cross-sectional area difference and the fat grade of the implant side.

CONCLUSION

Our results demonstrate psoas atrophy on the implant side compared to the non-operative side in post-unilateral implant patients. Post-operative hip implant rehabilitation may benefit from more focused psoas strengthening exercises to improve functional outcome.

[Hip joint contractures, leg length discrepancies, and spinopelvic alignment: impact on the development of osteoarthritis of the hip?]

Hip joint problems are common in every-day orthopedic practice. At the age of 60, approximately 5% of the German population suffer from symptomatic osteoarthritis of the hip. One of the main trigger is the morphological abnormality of the joint. Causes may also be overloading of the joint, developmental dysplasia of the hip with reduced coverage, as well as femoral or acetabular malpositioning, for example. The impact of hip joint contractures, leg length discrepancies, and the spinopelvic alignment and their prophylactic treatment in childhood, adolescence and early adulthood are discussed here.