Diana C. Sanchez-Ramirez, Marike van der Leeden, Dirk L. Knol, Martin van der Esch, Leo D. Roorda, Sabine Verschueren, Jaap van Dieën , Willem F. Lems, Joost Dekker
Amsterdam Rehabilitation Research Center Reade, 1040 HG Amsterdam, The Netherlands. E-mail: d.c.sanchezramirez@vu.nl
DOI: 10.2340/16501977-1087

Objective: To determine the association of postural control with muscle strength, proprioception, self-reported knee instability and activity limitations in patients with knee osteoarthritis.
Methods: A total of 284 patients with knee osteoarthritis from the Amsterdam Osteoarthritis cohort were included. Postural control was assessed using the One-Leg Stand Test (OLST), in which the patients were asked to stand on one leg for 30 s. Muscle strength (isokinetic dynamometer), proprioception (joint motion detection threshold) and self-reported knee instability (episodes of buckling, shifting or giving way) were also assessed. Activity limitations were assessed using the Get Up and Go (GUG) test, the walking up-down stairs test, and Western Ontario and McMaster University Osteoarthritis Index – Physical Function subscale. Regression analyses were used to assess the associations.
Results: Muscle weakness (p = 0. 02) and proprioceptive inaccuracy (p < 0. 001) were associated with decreased postural control. Decreased postural control was associated with less time performing the GUG test (p < 0. 001) and the walking up-down stairs test (p < 0. 001). These associations were found after adjustment for relevant confounders.
Conclusion: In patients with knee osteoarthritis, decreased postural control is associated with muscle weakness, proprioceptive inaccuracy and performance-based activity limitations. These results highlight the importance of including assessment and training of postural control in this group of patients.