Bone and Mineral Density Disorders
Decreased bone mineral density (BMD) and increased risk of fracture with minimal trauma is common in patients with moderate to severe CP, especially those who are nonambulatory. By the age of 10 years, most nonambulatory children have osteopenia, as defined by BMD z score of to progress, regardless of the patient's skeletal maturity (65).
The risk of progression is greatest for patients with quadriparesis, increased spasticity, a larger curve, a younger age, poor sitting balance, or pelvic obliquity (61).Upper extremity
Spasticity and muscle imbalances can often lead to joint deformities in the upper extremity. The shoulder is often positioned in an adducted and internally rotated position. Spasticity in the biceps, brachiora- dialis, and the brachialis frequently result in elbow flexion contractures. Elbow flexion contractures less than 30 degrees rarely have functional significance. Forearm pronation deformities are common and can significantly affect functional use of the hand. The most common deformity of the wrist is flexion, typically with ulnar deviation (Fig. 8.11). The most common finger deformities are flexion and swan neck deformities due to hand intrinsic muscle spasticity. A thumb in palm deformity is commonly seen with adduction at the carpometacarpal joint, which may be associated with hyperextension of the metacarpophalangeal and interphalangeal joints.