Changes in sagittal ground reaction forces after intra-articular hyaluronate injections for knee osteoarthritis.
OBJECTIVE
To examine the gait patterns and the sagittal ground reaction forces (GRFs) in persons with knee osteoarthritis (OA) after intra-articular injection of hyaluronate and to investigate the duration of its treatment effectiveness.


METHODS
Case-comparison study.


METHODS
Gait laboratory in a tertiary care center.


METHODS
Fifteen subjects (30 knees) with symptomatic knee OA (stage I or II, according to the Ahlbäck grading system), and 15 age-, mass-, and gender-matched non-OA control subjects (30 knees).


METHODS
After initial gait analysis, the group with knee OA received 5 weekly intra-articular injections of hyaluronate to bilateral knees. Gait analysis was performed again for the group with knee OA after the completion of hyaluronate injections.


METHODS
Forceplate sagittal GRFs and gait parameters of velocity, cadence, step length, and stride time.


RESULTS
The distinctive 2-peak force vector GRF was lost in persons with knee OA. The first peak rise time was significantly delayed (P<.05). The group with knee OA also revealed slower walking velocity and cadence, as well as longer stride time, than the control group (P<.05). The distinctive 2-peak force vector GRF diagram could be recovered in patients with knee OA after the completion of hyaluronate injections.


CONCLUSIONS
Gait patterns and GRFs improved significantly after intra-articular knee injection of hyaluronate in persons with Ahlbäck stages I and II knee OA. The clinical treatment effect was immediate and may last for 6 months or more.
Tang
Simon F
SF
Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, 5 Fu-Hsin Street, Kwei-Shan, Tao-Yuan 333, Taiwan. fttang@adm.cgmh.org.tw
Chen
Carl P
CP
Chen
Max J
MJ
Pei
Yu-Cheng
YC
Lau
Yiu-Chung
YC
Leong
Chau-Peng
CP
D000276:Adjuvants, Immunologic / Q000627:therapeutic use*; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D006820:Hyaluronic Acid / Q000627:therapeutic use*; D007270:Injections, Intra-Articular; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000188:drug therapy* / Q000503:physiopathology; D016896:Treatment Outcome
D000276:Adjuvants, Immunologic; D006820:Hyaluronic Acid