Validity, Agreement and Reliability of the ForceFrame Dynamometer in Patients with Anterior Cruciate Ligament Injury.

Background: Restoring maximal muscle strength of the knee extensors (KE) and knee flexors (KF) following anterior cruciate ligament (ACL) injury and ACL reconstruction is of great importance to reduce the re-injury rate after ACL reconstruction and to reduce the risk of knee osteoarthritis. Therefore, it is essential that clinicians and healthcare providers use valid and reliable measures to assess knee muscle strength to ensure a safe return to sport. Purpose: To evaluate the reliability (test-retest reliability, inter-tester reliability and test-retest agreement) and validity (concurrent validity, convergent validity and ForceFrame (FF) vs. isokinetic dynamometer (ID) agreement) of the ForceFrame (FF) dynamometer during isometric testing of the knee extensors and flexors. Study Design: Cross-sectional study. Material and Methods: Twenty-seven participants with ACL injury or reconstruction were recruited for participation in this study. maximal voluntary isometric contration (MVIC) of the knee extensors and flexors was tested on two separate days. Day one included validity assessments with FF, a gold-standard ID and a handheld dynamometer (HHD). Day two included reliability assessments with FF performed by two assessors. Main outcome measures were day-to-day test-retest reliability and agreement and inter-tester reliability of FF, and concurrent validity (FF vs. an ID and a HHD). Reliability was tested as test-retest and inter-tester reliability using interclass correlation coefficient (ICC), while agreement was tested using Bland & Altman plots with limits of agreement (LOA), standard error of measurement (SEM) and smallest detectable change (SDC). Concurrent validity between FF, ID, and HHD was assessed using Pearson's correlations and mean difference was evaluated by Bland & Altman plots. Results: Twenty-seven participants (10 females, 17 males) with a median age of 25 years (range 19-60) were included in this study. There was a good day-to-day test-retest reliability for MVIC of KE (ICC=0.77, CI95:0.48-0.90) and KF (ICC=0.83, CI95:0.61-0.92) and excellent inter-tester reliability for MVIC of KE (ICC=0.97, CI95:0.94-0.98) and KF (ICC=0.93, 95CI:0.85-0.97). Standard error of measurement (SEM) was 8% and 9%, while the smallest detectable change (SDC) was 22% and 27% for KE and KF, respectively. FF showed fair concurrent validity compared to ID for KE (r=0.56), poor concurrent validity for knee flexors (KF (r=0.24) and compared to HHD a moderate correlation for KE (r=0.74) and poor correlation for KF (r=0.12). Bland & Altman plots between FF and the ID showed a mean difference of -0.51 Nm/kg for KE and -0.32Nm/kg for KF. Conclusions: FF can be used to obtain reliable and valid results to assess MVIC of the KE, but not the KF. It should be noted that absolute results produced by the FF may be considered an underestimation of actual MVIC. The test position to assess KF in FF does not appear to be optimal, and different test-positions may be considered. Level of evidence: Level 3.

Associations between changes in leg extensor muscle power and physical function after supervised exercise in patients with hip osteoarthritis. Secondary analysis from the hip booster trial.

Objective: To investigate associations between changes in leg extensor muscle power of the affected limb (ΔLEP) and changes in physical function after 12 weeks of progressive resistance training (PRT) or neuromuscular exercise (NEMEX) in patients with hip osteoarthritis. Design: Secondary analyses of a randomized controlled trial. From 160 participants enrolled in the clinical trial and cluster randomized to PRT (n â€‹= â€‹82) or NEMEX (n â€‹= â€‹78), a total of 147 (92%) had complete follow-up data and were included in the analyses. Simple linear and multivariate linear regression models estimated the crude and adjusted associations between ΔLEP normalized to body weight (watt/kg) and changes in performance-based and patient-reported measures of physical function. Results: Adjusted estimates [95% confidence intervals] showed associations between ΔLEP (watt/kg) and changes in 30-s chair stand test (ß: 2.34 [1.33; 3.35], R2: 0.13), 9-step timed stair climb test (ß: -1.47 [-2.09; -0.85], R2: 0.38), 40-m fast paced walking test (ß: -2.20 [-3.30; -1.11], R2: 0.09), Activities of Daily Life function (ß: 8.63 [3.16; 14.10], R2: 0.23) and Sport and Recreation function (ß: 10.57 [2.32; 18.82], R2: 0.21) subscales from the Hip disability and Osteoarthritis Outcomes Score. Group allocation to PRT did not lead to greater regression coefficients than in NEMEX. Conclusions: Changes in leg extensor muscle power after supervised exercise are consistently associated with changes in physical function across performance-based and patient-reported measures in patients with hip osteoarthritis. These associations seem to be independent of allocation to PRT or NEMEX.

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.

Exercise compared to a control condition or other conservative treatment options in patients with Greater Trochanteric Pain Syndrome: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES: To estimate the effectiveness of exercise at end of treatment and long-term follow-up compared to a control condition or other conservative treatments in patients with Greater Trochanteric Pain Syndrome (GTPS). METHODS: Databases were searched September 2021 and updated September 2023. Randomized controlled trials (RCT) comparing exercise interventions for patients with GTPS, to a control condition; corticosteroid injection; shock wave therapy; or other types of exercise programs were included. Risk of bias was assessed using the ROB2 tool. Meta-analyses were performed using a random-effects model. The certainty of the evidence was rated by the GRADE approach. RESULTS: Six RCTs including a total of 733 patients with GTPS were included. Three trials compared exercise to sham exercise or wait-and-see control groups, two trials compared exercise to corticosteroid injection, two trials compared exercise to shockwave therapy, and one trial compared exercise to another type of exercise. Meta-analyses showed that in the long term, exercise slightly reduces hip pain and disease severity, while slightly improving patient-reported physical function and global rating of change compared to a control condition. No serious adverse events were reported. Compared to corticosteroid injection, exercise improves long-term global rating of change. CONCLUSION: The current evidence supports a strong recommendation for exercise as first line treatment in patients clinically diagnosed with GTPS. Compared to corticosteroid injection, exercise is superior in increasing the likelihood that a patient experiences a meaningful global improvement. These results are based on few trials and a moderate number of patients. REGISTRATION: This review was prospectively registered in the PROSPERO database of systematic reviews (ID: CRD42021261380). CONTRIBUTION OF PAPER.

Muscle Strength, Oxygen Saturation and Physical Activity in Patients with Chronic Exertional Compartment Syndrome Compared to Asymptomatic Controls.

Background: One of the most common causes of exercise-induced pain in the lower leg is chronic exertional compartment syndrome (CECS). Research is limited on muscle strength, oxygen saturation and physical activity in patients with CECS. Purpose: To compare muscle strength, oxygen saturation, and daily physical activity between patients with CECS and matched asymptomatic controls. A secondary purpose was to investigate the association between oxygen saturation and lower leg pain in patients with CECS. Study Design: Case-control study. Method: Maximal isometric muscle strength of the ankle plantar and dorsiflexors was tested in patients with CECS and sex- and age-matched controls using an isokinetic dynamometer and oxygen saturation (StO2) during running was tested by near infrared spectroscopy. Perceived pain and exertion were measured during the test using the Numeric Rating Scale and Borg Rating of Perceived Exertion scale and the exercise-induced leg pain questionnaire. Physical activity was assessed by accelerometry. Results: Twenty-four patients with CECS and 24 controls were included. There were no differences in maximal isometric plantar or dorsiflexion muscle strength between patients and controls. Baseline StO2 was 4.5pp (95% CI: 0.7;8.3) lower for patients with CECS than for controls, whereas no difference existed when they experienced pain or reached exhaustion. No differences were found in daily physical activities, except that on average, patients with CECS spent less time cycling daily. During the StO2 measurement, patients experienced pain or reached exhaustion while running significantly earlier than the controls (p<0.001). StO2 was not associated with leg pain. Conclusion: Patients with CECS have similar leg muscle strength, oxygen saturation and physical activity levels as asymptomatic controls. However, patients with CECS experienced significantly higher levels of lower leg pain than the controls during running, daily activities and at rest. Oxygen saturation and lower leg pain were not associated. Level of Evidence: Level 3b.

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.

Blood Flow Restricted Walking in Elderly Individuals with Knee Osteoarthritis: A Feasibility Study.

OBJECTIVE: To investigate whether blood flow restricted walking exercise is feasible in patients with knee osteoarthritis, and to examine changes in functional performance and self-reported function. DESIGN: Feasibility study. PATIENTS AND METHODS: Fourteen elderly individuals diagnosed with knee osteoarthritis participated in 8-10 weeks of outdoor walking (4 km/h, 20 min/session, 4 times/week) with partial blood flow restriction applied to the affected leg. Adherence, dropouts and adverse events were registered. Timed Up and Go test, 30-s sit-to-stand performance, 40-m fast-paced walk speed, stair-climbing and Knee Osteoarthritis Outcome Score were assessed pre- and post-training. RESULTS: Nine participants completed the intervention, while 5 participants withdrew (4 due to intervention-related reasons). In non-completing participants baseline body mass index (BMI) (p = 0.05) and knee pain (p = 0.06) were higher, while gait performance (p = 0.04) was lower. Considering completed case data, the training-adherence rate was 93%, while mean knee pain in the affected leg was 0.7 on a numerical rating scale of 0-10. Functional performance improved, while self-reported function remained unchanged. CONCLUSION: Blood flow restricted walking exercise appeared feasible in patients with knee osteoarthritis. Participants who completed the intervention protocol demonstrated improvements in functional performance, with no changes in self-reported function.

Is progressive resistance training feasible in patients with symptomatic external snapping hip?

BACKGROUND: Little is known about the feasibility of applying progressive resistance training (PRT) to patients with symptomatic external snapping hip (SESH). PURPOSE: To investigate whether PRT is feasible in patients with SESH and to report changes to hip function, awareness of the hip joint and muscle strength following PRT. METHODS: Feasibility was measured by drop-out rate, adverse events, pain exacerbation (VAS) and adherence to PRT. At baseline and the end of treatment, patients completed the Copenhagen Hip and Groin Outcome Score (HAGOS), the Forgotten Joint Score (FJS), maximal voluntary isometric (MVC) and dynamic hip muscle strength and a loaded stair test (LST). RESULTS: Three out of nine included female patients (33%) dropped out. Pain scores were acceptable (VAS ≤ 50 mm) in 76% of all training sessions, and an overall decrease in pain during PRT was found (-10 mm, 95% CI [-3; -18]). For those who completed the intervention, training adherence was 97 ± 4%. Paired analyzes showed improvements in all HAGOS subscales, FJS, muscle strength and the LST. CONCLUSION: Progressive resistance training seems feasible in a subset of patients with SESH despite a high drop-out rate. The present study suggests large effect sizes for hip pain, function, awareness and muscle strength.

[Effect of training in the different stages of hip osteoarthritis].

Training may relieve symptoms in patients with mild to severe hip osteoarthritis and in patients who have received a total hip arthroplasty. Patients may train like healthy individuals. The effectiveness of training is dependent on sufficient dose and intensity. In this review, we suggest to prioritise research performed in the pre-clinical or in the mild to moderate stage of hip osteoarthritis where there is insufficient evidence on whether training has a disease-modifying effect or not. We also suggest that trials with long-term follow-up are performed for these patient groups.

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.

[Blood-flow restricted walking exercise as rehabilitation for a patient with chronic knee osteoarthritis].

In this case report, a 75-year-old woman with symptomatic knee osteoarthritis completed nine weeks (27 sessions, nine supervised) of blood-flow restricted (BFR) walking exercise without any discomfort and a 100% training adherence. BFR walking was well tolerated by the patient and resulted in improvements in functional capacity: 30-sec. sit-to-stand, timed up and go, 40-m walk test, and stair climb test. However, no positive changes were noted for maximal knee extensor and knee flexor strength or in Knee Osteoarthritis Outcome Scores.

[Treatment of external snapping hip with targeted resistance training intervention].

This case report describes an 18-year-old woman, who had symptomatic bilateral external and internal snapping hip and completed 28 of 30 training sessions during a 12-week resistance training intervention. The intervention proved to be feasible and improved maximal strength in hip abduction and extension measured with Isokinetic Dynamometry. Improvements were also seen in The Copenhagen Hip and Groin Outcome Score, and The Forgotten Joint Score. Furthermore, visual analog scale pain markedly decreased after the intervention.