Plantar- and dorsiflexor strength in prepubertal girls with juvenile idiopathic arthritis.
OBJECTIVE
To compare lower-leg strength of young girls with polyarticular juvenile idiopathic arthritis (JIA) with that of healthy, age-matched controls.


METHODS
Isometric and isokinetic strength tests of the plantar- and dorsiflexors. All strength measures were made at an ankle angle of 90 degrees. Isokinetic plantar- and dorsiflexor measures were made at 15 degrees/s during shortening (concentric) and lengthening (eccentric) actions.


METHODS
Strength testing laboratory.


METHODS
Ten prepubertal girls diagnosed with JIA and 10 healthy girls.


METHODS
Not applicable.


METHODS
Isometric and isokinetic plantar- and dorsiflexor strength.


RESULTS
Isometric plantar- and dorsiflexion torques were significantly lower (48% and 38% respectively; P<.05) for the children with JIA than for the controls. The JIA group also produced lower shortening plantarflexion torques (52%, P<.05). Lengthening plantarflexor torques did not differ significantly between the 2 groups (P<.05). Controls were stronger than the JIA group for both shortening and lengthening maximal dorsiflexor actions (P<.05). All children were 4 to 5 times stronger in plantarflexion than in dorsiflexion.


CONCLUSIONS
Girls with JIA had significantly less plantar- and dorsiflexor strength than age-matched, healthy peers. The reduced strength of children with JIA is likely to affect function in daily activities and probably contributes to reduced levels of physical activity.
Woman and Child Health and Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Eva
E
Broström
Maria M
MM
Nordlund
Andrew G
AG
Cresswell
D000203:Activities of Daily Living; D000367:Age Factors; D000842:Ankle / Q000503:physiopathology*; D001171:Arthritis, Juvenile / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D001827:Body Height; D015992:Body Mass Index; D016022:Case-Control Studies; D002648:Child; D018450:Disease Progression; D005260:Female; D005528:Foot / Q000503:physiopathology*; D006801:Humans; D007537:Isometric Contraction; D007551:Isotonic Contraction; D018908:Muscle Weakness / Q000175:diagnosis / Q000209:etiology*; D026741:Physical Therapy Modalities / Q000379:methods; D016059:Range of Motion, Articular; D012727:Sex Characteristics; D019415:Torque