Postural control during stance in paraplegia: Effects of medially linked versus unlinked knee-ankle-foot orthoses

Objective: To investigate the effect of medially linking knee-ankle-foot or thoses (KAFOs) on postural stability and sway during (1) quiet standing and (2) functional activities for persons with spinal cord injury (SCI). Design: A randomized, mixed design, with the factors being activity (quiet standing and two function-mimicking tasks), SCI (present or not), and type of orthosis used in SCI group (linked or unlinked KAFO). Participants: Nine men with T5 to T12 paraplegia, 8 of whom had complete le sions and 1 with some sacral sparing (American Spinal Injury Association gr ade B) without proprioception, matched to 9 able-bodied men. Main Outcome Measures: Mean amplitude of sway and sway path in anteroposter ior and mediolateral directions, derived from center of pressure measuremen ts on a force platform. Results: All men with SCI were able to stand unsupported and perform functi on-mimicking activities in medially linked KAFOs; however, when wearing unl inked KAFOs only 5 could maintain balance during quiet stance and 3 could m aintain balance during activity. Significant differences were found between linked and unlinked KAFOs; side-to-side mean amplitude of sway was less an d sway path was greater for SCI subjects when they wore the linked KAFOs. Conclusion: Medial linkage of bilateral KAFOs provides an effective strateg y to improve stability and increase postural control for persons with SCI, facilitating performance of functional activities during standing without u pper limb support. (C) 1999 by the American Congress of Rehabilitation Medicine and the Americ an Academy of Physical Medicine and Rehabilitation.