Associated Strengthening Exercises to Undenatured Oral Type II Collagen UCII. A Randomized Study in Patients Affected by Knee Osteoarthritis
Ana Paula Costa, Verine Cunha Teixeira, Mário José dos Santos Pereira, Patrícia Mota Ferreira, P.A. Kuplich, Marcelo Baptista Döhnert, Jucélia Fátima da Silva Güths, Rodrigo Boff Daitx
Abstract
Background. Osteoarthritis (OA) is a chronic joint disease characterized by progressive degeneration of articular cartilage. It affects 20-25% of the population older than 45 years. The objective was to evaluate the effect of combining muscle strengthening exercises with the administration of oral type II undenatured collagen formulation (UC-II) in people with knee OA. Methods. A double-blind, placebo-controlled, randomized controlled trial with 60 patients with knee OA, randomly divided into the following groups: UC-II and physiotherapy group (CPG), placebo UC-II and physiotherapy group (PCPG), and physiotherapy group (PG). For groups using an oral type II undenatured collagen formulation, UC-II, 40 mg/day UC-II was administered for 90 days. Muscle strengthening exercises were associated with neuromuscular electrical stimulation (NMES), being performed three times a week for 30 days. At 30 and 90 days and six months after the intervention, the following were evaluated: pain, quality of life, functional capacity, muscle strength, and joint mobility. Results. Pain improved in all intervention groups, with no difference between groups. Quadriceps muscle strength increased in the CPG (p<0.005) and PG (p<0.05), the same being observed for active and passive knee flexion mobility (p<0.05). All groups decreased the TUG test execution time after 30 days (p<0.005 for the CPG and PG, and p<0.05 for the PCPG), but only the CPG and PG maintained the scores at 90-day and six-month assessments (p<0.005). Regarding the 6MWT, only the CPG increased the distance covered in all assessments (p<0.005). The PG traveled a greater distance than the PCPG at the 90-day assessment (p<0.05). The WOMAC score decreased significantly in all intervention groups. The Lequesne score decreased in all groups; however, the CPG and PG showed lower values at 30 days (p<0.005). Conclusions. Muscle strengthening exercises improved pain, mobility, strength, and function in knee OA patients. The association of UC-II seems to have accentuated the effect of exercise on this clinical improvement, especially in the long term.