Which contractures are most typical at thoracic level postural deviations and contractures?

Which contractures are most typical at thoracic level postural deviations and contractures?

• A. Hip flexion, abduction, and external rotation contractures
• B. Knee flexion and ankle plantarflexion contractures
• C. Kyphoscoliosis
• D. Increased lumbar lordosis

Answer: (A)

When a spina bifida lesion is at the thoracic level, the hip muscles become imbalanced because the trunk and some hip stabilizers are weak while others pull the hip into a fixed position. This tends to produce a pattern where the hip sits in flexion, is abducted, and held in external rotation. Over time, these muscle imbalances turn into fixed shortening—contractures—at the hip in those three directions. That combination is the classic postural pattern for high thoracic involvement, so hip flexion, abduction, and external rotation contractures are the most typical. Knee flexion and ankle plantarflexion contractures are more related to lower-level involvement or to long-standing crouched postures and foot deformities, not the characteristic hip pattern seen with thoracic lesions. Kyphoscoliosis is a spinal deformity arising from trunk muscle weakness and alignment changes, not a muscle contracture at a joint. Increased lumbar lordosis is another postural change, not the hip contracture pattern typical of thoracic-level lesions.

When a spina bifida lesion is at the thoracic level, the hip muscles become imbalanced because the trunk and some hip stabilizers are weak while others pull the hip into a fixed position. This tends to produce a pattern where the hip sits in flexion, is abducted, and held in external rotation. Over time, these muscle imbalances turn into fixed shortening—contractures—at the hip in those three directions. That combination is the classic postural pattern for high thoracic involvement, so hip flexion, abduction, and external rotation contractures are the most typical.

Knee flexion and ankle plantarflexion contractures are more related to lower-level involvement or to long-standing crouched postures and foot deformities, not the characteristic hip pattern seen with thoracic lesions. Kyphoscoliosis is a spinal deformity arising from trunk muscle weakness and alignment changes, not a muscle contracture at a joint. Increased lumbar lordosis is another postural change, not the hip contracture pattern typical of thoracic-level lesions.