Functional movement assessment for individuals with knee osteoarthritis

The relationships between dynamic stability, lower extremity strength, and functional performance are not well-understood for individuals with knee pain due to osteoarthritis. The series of studies presented in this dissertation incorporate the assessment of functional movements for healthy older adults, individuals with symptoms of knee osteoarthritis, and individuals following total knee arthroplasty. The functional activities investigated in these populations included stair descent and sit-to-stand. This research was completed through a combination of kinematic techniques of motion analysis and kinetic assessment using multiple force platforms to evaluate joint moments, center of pressure parameters and weight-bearing asymmetry. The findings can be summarized as follows: 1) Kinetic and kinematic indicators of sit-to-stand movement may be standardized for healthy individuals of various ages without regard to initial positioning; 2) Individuals post-total knee arthroplasty compensate for residual physical deficits by utilizing upper extremity support and altered joint loading to perform sit-to-stand successfully; and 3) Altered joint loading and compensatory weight-bearing asymmetry allows individuals with mild to moderate knee pain to perform sit-to-stand and stair descent while maintaining dynamic stability. Older adults with symptoms of osteoarthritis appear to compensate for physical limitations of reduced joint mobility, strength deficits, and pain by adjusting joint loads and altering patterns for movement

PLEASE SCROLL DOWN FOR ARTICLE Ergonomics The effects of age and type of carrying task on lower extremity kinematics

To cite this Article Gillette, Jason C. , Stevermer, Catherine A. , Miller, Ross H. , Meardon, Stacey A. andSchwab, Charles V.(2010) 'The effects of age and type of carrying task on lower extremity kinematics ', Ergonomics, 53: 3,[355][356][357][358][359][360][361][362][363] Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. The purpose of this study was to determine the effects of age, load amount and load symmetry on lower extremity kinematics during carrying tasks. Forty-two participants in four age groups (8-10 years, 12-14 years, 15-17 years and adults) carried loads of 0%, 10% and 20% body weight (BW) in large or small buckets unilaterally and bilaterally. Reflective markers were tracked to determine total joint range of motion and maximum joint angles during the stance phase of walking. Maximum hip extension, hip adduction and hip internal rotation angles were significantly greater for each of the child/adolescent age groups as compared with adults. In addition, maximum hip internal rotation angles significantly increased when carrying a 20% BW load. The observation that the 8-10-year-old age group carried the lightest absolute loads and still displayed the highest maximum hip internal rotation angles suggests a particular necessity in setting carrying guidelines for the youngest children. Statement of Relevance: Bucket-carrying tasks were analysed as a function of age group, load amount and load symmetry. Hip joint rotations significantly increased when carrying 20% BW loads and in children as compared to adults, which suggests a particular necessity in setting carrying guidelines for the youngest age group (8-10 year olds)

Muscle activity amplitudes and co-contraction during stair ambulation following anterior cruciate ligament reconstruction

The purpose of this study was to compare muscle activity amplitudes and co-contraction in those with anterior cruciate ligament (ACL) reconstruction to healthy controls during stair negotiation. Eighteen participants with unilateral ACL reconstruction and 17 healthy controls performed stair ascent and descent while surface electromyography was recorded from knee and hip musculature. During stair ascent, the ACL group displayed higher gluteus maximus activity (1–50% stance, p = 0.02), higher vastus lateralis:biceps femoris co-contraction (51–100% stance, p = 0.01), and higher vastus lateralis:vastus medialis co-contraction (51–100% stance, p = 0.05). During stair descent, the ACL group demonstrated higher gluteus maximus activity (1–50% stance, p = 0.01; 51–100% stance, p \u3c 0.01), lower rectus femoris activity (1–50% stance, p = 0.04), higher semimembranosus activity (1–50% stance, p = 0.01), higher gluteus medius activity (51–100% stance, p = 0.01), and higher vastus medialis:semimembranosus co-contraction (1–50% stance, p = 0.02). While the altered muscle activity strategies observed in the ACL group may act to increase joint stability, these strategies may alter joint loading and contribute to post-traumatic knee osteoarthritis often observed in this population. Our results warrant further investigation to determine the longterm effects of altered muscle activity on the knee joint following ACL reconstruction