Architecture of the medial gastrocnemius in children with spastic diplegia.

Ultrasound images were obtained of the medial gastrocnemius at different ankle joint positions with the knee extended. Fascicle length and deep fascicle angle were measured in five normally developing adults (mean age 33 years, age range 24 to 36 years) and in five normally developing children (mean age 7.8 years, age range 7 to 11 years), and in seven children with spastic diplegia (mean age 10 years, age range 6 to 13 years). These architectural variables were similar in the groups of normally developing adults and children. Importantly, no statistical difference could be found between the normally developing children and those with diplegia for fascicle length. Deep fascicle angles were reduced significantly in the clinical group at a particular ankle joint angle but not at the resting angles. The difference in deep fascicle angles is explained as a function of resting muscle length and is not attributed any clinical importance. Our results do not explain the structural origin of muscle contracture explicitly. However, they do indicate that most of the fixed shortness in the medial gastrocnemii of ambulant children with spastic diplegia is not due to reduced muscle fibre length. We suggest that muscle contracture may be better explained in terms of shortness of the aponeuroses of pennate muscles, such as the medial gastrocnemius, through reduced muscle fibre diameter.

Drug-induced systemic lupus erythematosus associated with etanercept therapy.

Specific antagonists of tumour necrosis factor (TNF)-alpha have rapidly gained popularity for the treatment of rheumatoid arthritis. The monoclonal antibody against TNF-alpha, infliximab, has been associated with induction of systemic lupus erythematosus (SLE); however, there have been no published reports of drug-induced SLE associated with the soluble TNF-alpha receptor etanercept. We describe four female patients who developed signs and symptoms of SLE during treatment with etanercept; in two SLE was unambiguous. On diagnosis of SLE, etanercept was discontinued and the SLE-related symptoms promptly resolved. Etanercept should be considered in the list of agents associated with drug-induced SLE.