Kari L Loverro1, Anne Khuu2, Pei-Chun Kao3, Cara L Lewis2. 1. Department of Physical Therapy & Athletic Training, PhD Program in Rehabilitation Sciences, College of Health & Rehabilitation Sciences: Sargent College, Boston University, 635 Commonwealth Ave., Boston, MA, United States; Natick Soldier Research Development and Engineering Center, 10 General Greene Ave., Natick, MA, United States. Electronic address: kloverro@bu.edu. 2. Department of Physical Therapy & Athletic Training, PhD Program in Rehabilitation Sciences, College of Health & Rehabilitation Sciences: Sargent College, Boston University, 635 Commonwealth Ave., Boston, MA, United States. 3. Department of Physical Therapy, 3 Solomont Way, Suite 5, University of Massachusetts Lowell, Lowell, MA, United States.
Abstract
BACKGROUND: Individuals with developmental dysplasia of the hip (DDH) often report hip pain and exhibit gait adaptations. Previous studies in this patient population have focused on average kinematic and acceleration measures during gait, but have not examined variability. RESEARCH QUESTION: Do individuals with hip pain and DDH have altered kinematic variability or local dynamic stability (LDS) compared to individuals without hip pain? METHODS: Twelve individuals with hip pain and DDH and 12 matched controls walked for two minutes on a treadmill at three speeds: preferred, fast (25% faster than preferred), and prescribed (1.25 m/s). Kinematic variability of spatiotemporal measures, joint and segment angles, and LDS of the trunk were calculated for each speed. RESULTS: At the prescribed speed, individuals with hip pain and DDH had more kinematic variability than controls at the hip, pelvis, and trunk as well as greater variability in spatiotemporal measures. LDS was not different between groups. Kinematic variability of the joints decreased and LDS of the trunk increased (i.e., increased gait stability) with increased speed. SIGNIFICANCE: Individuals with hip pain and DDH had greater kinematic variability compared to individuals without hip pain when walking at the same prescribed speed, indicating either an adaptation to pain or reduced neuromuscular control. LDS of the trunk was not different between groups, suggesting that hip pain does not affect overall gait stability. Kinematic variability and LDS were affected by walking speed, but in different ways, emphasizing that these measures quantify different aspects of walking behavior. Published by Elsevier B.V.
BACKGROUND: Individuals with developmental dysplasia of the hip (DDH) often report hip pain and exhibit gait adaptations. Previous studies in this patient population have focused on average kinematic and acceleration measures during gait, but have not examined variability. RESEARCH QUESTION: Do individuals with hip pain and DDH have altered kinematic variability or local dynamic stability (LDS) compared to individuals without hip pain? METHODS: Twelve individuals with hip pain and DDH and 12 matched controls walked for two minutes on a treadmill at three speeds: preferred, fast (25% faster than preferred), and prescribed (1.25 m/s). Kinematic variability of spatiotemporal measures, joint and segment angles, and LDS of the trunk were calculated for each speed. RESULTS: At the prescribed speed, individuals with hip pain and DDH had more kinematic variability than controls at the hip, pelvis, and trunk as well as greater variability in spatiotemporal measures. LDS was not different between groups. Kinematic variability of the joints decreased and LDS of the trunk increased (i.e., increased gait stability) with increased speed. SIGNIFICANCE: Individuals with hip pain and DDH had greater kinematic variability compared to individuals without hip pain when walking at the same prescribed speed, indicating either an adaptation to pain or reduced neuromuscular control. LDS of the trunk was not different between groups, suggesting that hip pain does not affect overall gait stability. Kinematic variability and LDS were affected by walking speed, but in different ways, emphasizing that these measures quantify different aspects of walking behavior. Published by Elsevier B.V.
Entities:
Keywords:
Developmental dysplasia of the hip; Gait; Hip pain; Kinematic variability; Local dynamic stability
Authors: Ryan M Nunley; Heidi Prather; Devyani Hunt; Perry L Schoenecker; John C Clohisy Journal: J Bone Joint Surg Am Date: 2011-05 Impact factor: 5.284