Booster sessions for maintaining the effect of neuromuscular exercise and progressive resistance training in hip osteoarthritis: 12-month follow-up from a multicenter cluster-randomized controlled trial

Abstract

Objective: To investigate if exercise booster sessions (EBS) are superior to no further intervention (CON) in prolonging effects on functional performance after supervised exercise in patients with hip osteoarthritis (OA).

Methods: Multicenter, cluster-randomized, controlled, parallel-group, assessor-blinded, superiority trial conducted at hospitals and physiotherapy clinics. EBS participants were offered one group-based exercise session supervised by a physiotherapist at 1, 3, 5 and 7 months after the initial 3-month intervention. At each EBS, exercise complications were addressed and modifications were provided. CON participants received no further intervention. The primary outcome was change in the 30-second Chair Stand Test (30s-CST) from 3 to 12 months. Key secondary outcomes were changes in Pain and hip-related Quality of Life (QoL) subscales from the Hip disability and Osteoarthritis Outcomes Score (HOOS).

Results: 160 participants with clinically diagnosed hip OA enrolled from January 18th 2021 to April 28th 2023 and were cluster-randomized to EBS (N=84) or CON (N=76). The mean change (95% CI) from 3- to 12-month follow-up in 30s-CST was 0.8 (0.1; 1.5) chair stands in EBS and 0.5 (-0.1; 1.1) chair stands in CON (difference: 0.3 [-0.6; 1.2]), for HOOS pain it was 4.0 (-0.8; 8.7) points in EBS and 1.1 (-3.6; 5.7) points in CON (difference: 2.9 [-3.8; 9.6]), for HOOS QoL it was 6.8 (1.4; 12.2) points in EBS and 1.5 (-3.8; 6.8) points in CON (difference: 5.3 [-2.2; 12.9]).

Conclusions: EBS were not superior to CON for maintaining effects for functional performance, hip pain or hip-related quality of life at 12 months.

Registration: Clinicaltrials.gov (NCT04714047).

Keywords: Booster sessions; Exercise; Hip; Osteoarthritis; Pain; Physical function.