Diplegic cerebral palsy is the most common type of cerebral palsy. About two-thirds are associated with prematurity. Spasticity usually develops during the second year. Motor development is delayed but gradually improves to about age 7 years. Independent walking usually occurs if the infant achieves a motor level of about 12 months by the chronological age of 36 months.
Diplegia primarily involves the lower limb. Mild upper limb involvement is detected by careful examination. Severity varies. Often, involvement is asymmetrical. Perform standard examination.
A flexed gait is common in diplegia and may have several causes. Crouch is often accentuated by weakness and instability.
Treatment of Diplegic Cerebral Palsy
Management of diplegia is challenging because of the varied involvement, the potential for significant functional gains, and the risks of rendering the child less functional through inappropriate procedures.
Sagittal deformity Patterns of deformity as reported by Rodda and colleagues may be useful in planning management. As the group number increases, the equinus becomes less but the proximal contractures become more severe and the age of walking is later. Over time, the classification for a patient may change, necessitating changes in management.
- Group I The ankle is in equinus, the knee is straight or in recurvatum. The hip and pelvis are normal. Botulinum toxin injection may be useful early. Later, operative lengthening may be necessary.
- Group II This pattern is called jump knee because it gives the subject the appearance of jumping up and down during gait. The hip and knee are flexed throughout stance, with equinus occurring in late stance. These children may be candidates for dorsal rhizotomy or multilevel single-event surgical release.
- Group III The hamstrings and psoas are spastic and contracted, and lengthening may be necessary.
- Group IV As with group III, hamstring and psoas spasticity and contracture may make lengthening necessary. Frequently, this crouch is due to overlengthening of the triceps or preexisting weakness. This is most commonly seen following tendo-Achilles lengthening without being combined with a hamstring lengthening procedure.
Operative treatment requires careful planning. Undertake correction at multiple levels during the same operative session. Choose fractional lengthenings and recessions to avoid overcorrection, preserve strength, and allow early return to walking. Avoid heel-cord lengthenings, complete releases of hamstrings, adductors, or iliopsoas at the lesser trochanter.
Consider providing walking aids and ankle-foot orthoses (AFOs); monitor the status of the hips for subluxation. This may require operative treatment. Operative correction addresses all problems in one session. The following procedures are generally considered useful in diplegia:
Rotational deformity Femoral rotational osteotomy at intertrochanteric level for combined varus; rotational correction or at the supracondylar level if the hip is stable. Rotate the tibia at the supramalleolar level.
Hip displacement Varus-rotational femoral osteotomy combined with a pelvic osteotomy such as the Pemberton, Dega, or triple innominate types. Intramuscular iliopsoas lengthening is added.
Hip flexion Psoas lengthening at the pelvic brim.
Knee flexion Fractional lengthening of the medial hamstrings.
Ankle equinus Fractional lengthening of the triceps or isolated gastrocnemius lengthening if only that muscle is contracted.
Flexible pes valgus Calcaneal lengthening is preferred to subtalar fusion or stiffening procedures.
Stiff valgus Calcaneal lengthening and subtalar fusion or calcaneal varus osteotomy.