Many theories have been proposed for the cause of Legg-Calve-Perthes disease in children. Scientists have explored thyroid function, blood conditions, and passive smoking among many other topics. In this study, researchers look at the role of protein C deficiency as a possible cause.
Legg-Calve-Perthes disease affects the hip in young children. Blood supply to the growth center of the hip (the capital femoral epiphysis) is cut off, causing the bone in this area to die. In time the blood supply comes back and the bone heals. Delayed or poor bone healing can lead to serious problems in the hip joint later in life.
Protein C levels were measured in three groups and compared to normal values. Protein C was studied because it is a common factor in blood clotting. The loss of blood supply in Perthes may be linked to too much clotting of the blood.
Two groups of patients were divided by active versus inactive disease. Adults with completed skeletal growth who did not have active disease were in the first group. Children with immature bone development and active disease were in the second group. The third group included children and young adults who didn’t have Perthes disease at all.
The results showed no protein C deficiency in any of the groups. Patients with Perthes had low levels but these were still in the normal range. Levels were compared in subjects exposed to passive smoke to those whose parents did not smoke. There was no difference between these two groups.
The authors conclude that there isn’t a true protein C deficiency in Perthes disease. Low values suggest a possible problem but not the root cause. Exposure to passive smoke was present in three-fourths of the Perthes groups. Altered protein C levels don’t appear to be the result of passive smoke.