title: Intra-articular intervention by hyaluronic acid for knee osteoarthritis can modify locomotor pattern of muscle activity.
abstract: OBJECTIVE
  To evaluate the muscle activation pattern of lower extremities can be modified by intraarticular injection of hyaluronic acid( IAHA).
  
  
  METHODS
  Twenty-three subjects with knee OA and 14 age-matched non-knee OA control subjects were recruited from an outpatient clinic. Three-dimensional gait analysis with using the MA- 100 EMG system was applied to measure the muscles activities. The quadriceps (QUA), hamstrings (HAM), tibialis anterior (TA), and medial gastrocnemius (MG) muscles were selected for this study. For the knee OA group, bilateral IA knee joint injections with HA were performed.
  
  
  RESULTS
  During the stance phase of gait cycle, the quadriceps, hamstring, and tibialis anterior muscles had longer muscle contraction duration in the knee OA patients as compared with the control group. The muscle activities of quadriceps, hamstrings, tibialis anterior, and medial gastrocnemius muscles recovered to a pattern similar to the control group after the completion of IA HA injections in knee OA patients. The H/Q ratio improved significantly after the IA HA injections, and also lasted up to a period of six months (p<0.01).
  
  
  CONCLUSIONS
  IA HA is an available treatment option as it effectively decreases co-contraction and improves motor activity of the lower extremity muscles. The improved muscle activities lasted up to a period up to six months.
authors: Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, Taiwan.
authors: Alice Chu-Wen
authors: AC
authors: Tang
authors: School of Sports Medicine, China Medical University, Taichung, Taiwan.
authors: Wei-Hsien
authors: WH
authors: Hong
authors: Department of Industrial Engineering and Management, Taipei University of Technology, Taipei, Taiwan.
authors: Hsieh-Ching
authors: HC
authors: Chen
authors: Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, Taiwan; School of Medicine, Chang Gung University, Taiwan. Electronic address: fttang@adm.cgmh.org.tw.
authors: Simon Fuk-Tan
authors: SF
authors: Tang
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D004576:Electromyography; D005260:Female; D005684:Gait / Q000502:physiology; D006801:Humans; D006820:Hyaluronic Acid / Q000627:therapeutic use*; D007270:Injections, Intra-Articular; D007719:Knee Joint / Q000502:physiology / Q000503:physiopathology*; D008124:Locomotion / Q000502:physiology; D035002:Lower Extremity; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology / Q000503:physiopathology; D020370:Osteoarthritis, Knee / Q000188:drug therapy*; D052097:Quadriceps Muscle / Q000502:physiology / Q000503:physiopathology*; D016896:Treatment Outcome; D055675:Viscosupplements / Q000627:therapeutic use*
chemical_list: D055675:Viscosupplements; D006820:Hyaluronic Acid
keywords: Gait; Hyaluronic acid; Intra-articular injection; Knee osteoarthritis; Muscle activation