[General and local growth disorders in chronic arthritis in childhood]

In juvenile chronic arthritis both general and localized growth disorders are found. The general growth rate is especially impaired in the severe forms of the disease. In addition, delayed puberty with retarded pubertal growth spurt can temporarily result in growth retardation. Long term treatment with high dosage corticosteroids may intensify the growth failure, leading to severe stunting. Local growth disturbances are caused primarily in the area of the affected joints and secondarily as a result of functional disorders. The individual joints react in a specific, age-dependent manner. Growth acceleration and retardation, as well as various deformities of the bone structures, can be observed. Hands, knees and feet present typical examples of different growth disorders. In the toddler the inflammatory growth stimulus predominates first. This leads to accelerated ossification of the wrist and ankle as well as growth increase in knees, fingers and toes. In the further course and in the older child, shortening and growth reduction predominate. Here the premature fusion of the bones observed for example in fingers and toes, but also in the area of the distal part of the ulna, plays an important role. Arthritis can lead to deformities in all the joints. These deformities are more severe in children with early onset of the disease. Secondary growth disorders are caused by minor use of the joints. When wrists or elbows are involved, the entire hand may remain smaller. In the feet the growth impairment is often even more prominent, due to arthritis of the hips, knees or ankles. Both the general and the local growth disorders can be compensated to a large extent if treatment is begun at an early stage and the disease can be brought to remission. It is of great importance to preserve mobility of the joints in view of the interaction between function and growth.