The results of the Baumann procedure (intramuscular lengthening of the gastrocnemius and soleus in the proximal part of the muscle) for correction of fixed gastrosoleus contracture in diplegic children are presented.

Eleven ambulatory children with diplegic type of cerebral palsy (mean age: 10 years) were operated for correction of fixed gastrosoleus contracture by the Baumann procedure as part of a multi-level, single-session surgery for gait improvement. Evaluation included clinical examination and gait analysis. Mean follow-up after surgery was 2.7 years.

Clinical examination demonstrated significant improvements in active and passive ankle dorsal flexion with maintenance of ankle plantar flexor power. Ankle kinematics showed an increase in the dorsal flexion at initial contact, an average angle in single limb support, and maximum dorsal flexion in swing. Although there was an increase in dorsal flexion at the beginning of push-off, the total range of motion during push-off was not affected. Ankle movement demonstrated better loading in stance, manifested by significant improvement in maximum flexor movement in the second half of single stance. Post-operatively there was a change from abnormal generation of energy to normal energy absorption in mid-stance. Positive action during pushoff was significantly increased.

It is known that the growth of muscle occurs at its musculo-tendinous junction. Anatomic and simulation studies have demonstrated differences in the muscle fasicle length and pennation angles. With the Baumann procedure, an intramuscular lengthening gives the best chance for functional adaptation in the muscle. When needed, the soleus can also be lengthened. Multiple incisions permit stretching of the muscle fibres even in severe deformities.