Muscle Function Tests as Supportive Outcome Measures for Performance-Based and Self-Reported Physical Function in Patients With Knee Osteoarthritis: Exploratory Analysis of Baseline Data From a Randomized Trial

Intermittent blood flow restriction with low-load resistance training for older adults with knee osteoarthritis: a randomized, controlled, non-inferiority trial protocol

BACKGROUND

Knee osteoarthritis (KOA) is a chronic musculoskeletal disorder characterized by pain and functional impairment. Blood flow restriction (BFR) with low-load resistance training (LLRT) demonstrates a similar improvement in clinical outcomes to high-load resistance training (HLRT) in treating KOA. It has not been established whether intermittent blood flow restriction (iBFR) with LLRT can lead to clinical outcomes that are comparable to those produced by continuous blood flow restriction (cBFR) with LLRT and HLRT. The aim of the proposed study is to evaluate the efficacy of iBFR with LLRT on pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), muscle strength, muscle mass, physical function, perceptions of discomfort and effort, and adherence in KOA patients.

METHODS

This is a three-arm, non-inferiority, randomized controlled trial utilizing blinded assessors. Two hundred thirteen participants will be randomly allocated to one of the following three groups: iBFR group-receiving 4 months of LLRT with iBFR, twice weekly (n = 71); cBFR group-receiving 4 months of LLRT with cBFR, twice weekly (n = 71); or HLRT group-receiving 4 months of HLRT without BFR, twice weekly (n = 71). The primary outcome is pain. The secondary outcomes include the WOMAC, muscle strength, muscle mass, physical function, perceptions of discomfort and effort, and adherence. Pain and WOMAC will be measured at the baseline and 4 and 12 months after randomizations. Muscle strength, muscle mass, and physical function will be measured at the baseline and 4 months after randomizations. The perceptions of discomfort and effort will be measured during the first and final sessions.

DISCUSSION

BFR with LLRT has a similar improvement in clinical outcomes as HLRT. However, cBFR may cause elevated ratings of perceived exertion and local discomfort, compromising patient tolerability and treatment adherence. If iBFR with LLRT could produce improvement in clinical outcomes analogous to those of HLRT and iBFR with LLRT, it could be considered an alternative approach for treating patients with KOA.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2300072820. Registered on June 26, 2023.

Sit-to-stand power predicts functional performance and patient-reported outcomes in patients with advanced knee osteoarthritis. A cross-sectional study

BACKGROUND

Lower limb muscle power is positively associated with functional performance and patient-reported outcomes (PROMs) and suggested as an important variable to evaluate in patients with advanced knee osteoarthritis (OA).

OBJECTIVES

To explore the association between muscle power derived from the 30-sec sit-to-stand test (STS power) with functional performance and PROMs compared to maximal isometric knee extensor strength (KE MVC) in male- and female patients with advanced OA.

STUDY DESIGN

Cross-sectional design.

METHODS

Eighty-six patients (66.6 [64.9-67.7]years) with advanced knee OA were included. Dependent variables were STS power and KE MVC. Independent variables were Timed Up&Go (TUG), 40-m fast-paced walk test (40mFWT), Knee injury and Osteoarthritis Outcome Score (KOOS) subscales.

COVARIATE

Age.

ANALYSES

Simple linear- and multiple regression analyses with and without adjusting for age. Pitman's test was used to evaluate differences in correlation strength among dependent variables.

RESULTS

STS power demonstrated a statistical relationship with TUG and 40mFWT for both sexes (β coefficients -1.11 to -4.36 (p < 0.05), r2 = 0.47-0.55 (p < 0.05)), and with KOOS Pain, ADL, and Sport for male patients (β coefficients 6.53 to 7.17 (p < 0.05), r2 = 0.29-0.33 (p < 0.05)). Knee extensor MVC demonstrated no relationship with any outcomes for male patients or female patients. STS power displayed statistically stronger correlation to functional performance.

CONCLUSION

STS power was associated with functional performance in both male patients and female patients suffering from advanced knee OA. Moreover, STS power was associated with KOOS Pain, Sport, and ADLin male patients. The assessment of STS power should be considered in the evaluation of patients with advanced knee OA.

TRIAL REGISTRATION NUMBER

NCT04081493.