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.
Broström
Eva
E
Woman and Child Health and Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Nordlund
Maria M
MM
Cresswell
Andrew G
AG
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