Efficacy of an acute bout of isometric wall squat exercise on pain sensitivity and clinical pain intensity in adults with knee osteoarthritis: a randomised controlled trial in outpatient physiotherapy clinics in Saudi Arabia.

OBJECTIVE

To investigate the efficacy of two volumes of acute isometric wall squat exercise on pain sensitivity (primary outcome: pressure pain threshold (PPT)) and intensity (secondary outcome) in adults with knee osteoarthritis.

DESIGN

A parallel-group randomised controlled trial.

SETTING

Outpatient physiotherapy clinics at hospitals in Saudi Arabia.

PARTICIPANTS

Participants (n = 90; mean (SD) age 49.0 (13.0) years) with chronic knee osteoarthritis, diagnosed by a specialist orthopaedic physician using radiographic evidence and clinical judgement, were recruited via two tertiary hospitals in Saudi Arabia.

INTERVENTION: Participants were stratified by sex and randomly allocated to one of three groups: isometric single-repetition wall-squat (ISO-SR; one repetition of a 3-min wall squat or to volitional fatigue at a 100° knee joint angle), isometric multiple-repetition wall-squat (ISO-MR; three repetitions of the same intervention) and control (quiet sitting for 7 min).

PRIMARY AND SECONDARY OUTCOME MEASURES: PPT was measured at the calf (primary site of interest), lumbar spine and forearm using a pressure algometer. Pain intensity was assessed using a visual analogue scale. Primary analyses compared changes between intervention and control groups. All participants were included in the ITT analysis.

RESULTS

The ISO-MR group had higher mean PPT ratings immediately postintervention in the calf (mean difference=9.4 (95% CI 5.6 to 13.2), p<0.001), forearm (4.0 (95% CI 1.2 to 6.9), p=0.006) and lumbar spine (5.4 (95% CI 2.4 to 8.4), p<0.001), compared with control. The ISO-SR group reported a greater increase in PPT when compared with control at the calf (5.8 (95% CI 2.0 to 9.6), p=0.003) and lumbar spine (3.7 (95% CI 0.7 to 6.8), p=0.015). There were no differences in clinical pain intensity between the groups.

CONCLUSIONS

Both the ISO-SR and ISO-MR exercises to volitional fatigue reduced pain sensitivity in patients with knee osteoarthritis. Neither exercise volume changed clinical pain intensity.

TRIAL REGISTRATION NUMBER: ClinicalTrials.gov registry (ID: NCT05605444).