Proprioceptive-neuromuscular-facilitation Training Reduces Knee Abduction Moment And Medial-muscle Co-activation Among Older Adults With Knee Osteoarthritis

Knee osteoarthritis (KOA) is one of the most common degenerative diseases, with which abnormal mechanical loading may be a factor leading to cartilage degradation. Knee abduction moment (KAM) and vastus medialis-medial gastrocnemius (VM-MG) co-activation indicate the loading at the medial compartment of the knee. PURPOSE: To explore the effects of proprioceptive-neuromuscular-facilitation (PNF) training on the KAM and VM-MG co-activation during walking among older adults with medial compartment knee osteoarthritis (MCKOA). METHODS: Twenty-seven older adults with MCKOA were recruited and allocated to the PNF (n = 14, 65.3 ± 4.6 years, 161.1 ± 7.5 cm, and 71.1 ± 10.0 kg) or the control (n = 13, 66.6 ± 7.0 years, 161.0 ± 10.9 cm, and 69.1 ± 13.6 kg) groups to receive PNF training or health lecture series for six weeks, three one-hour sessions per week. A motion capture system, synchronized with a force plate and an electromyography system, was used to collect KAM, VM and MG activation data before (week0) and after (week7) the interventions. Two-factor (time by group) ANOVA with repeated measures was used to analyze data. RESULTS: Significant interactions were detected in the KAM (p = 0.035, η2p = 0.166) and the VM-MG co-activation index (p = 0.004, η2p = 0.304). Compared to week0, KAM (week0: 0.38 ± 0.10, week7: 0.30 ± 0.15, p = .021, d = .967) and VM-MG co-activation index (week0: 62.08 ± 16.65, week7: 52.96 ± 19.46, p = .013, d = .501) decreased in the PNF group while remaining unchanged in the control group at week7. The KAM of the PNF group was lower than that of the control group at week7 (PNF group: 0.30 ± 0.15, Control group: 0.45 ± 0.16, p = .021, d = .605). CONCLUSION: The PNF training reduced KAM and VM-MG co-activation, inferring the PNF training decreased the potentially harmful loading at the medial compartment among older adults with MCKOA. This research was funded by the China Shandong Education Department under Grant Movement Science Research Innovation Team, grant number 2019-183.