Treatment outcome in 60 children with pathological fractures of the humerus caused by juvenile or aneurysmal bone cysts.

The treatment of pathological fractures of the humerus caused by juvenile or aneurysmal bone cysts (JBC/ABC) should be a single approach with a high success rate and low complication rate. This study evaluates how day by day treatment concepts fulfil these aims. Children below 15 years of age with a pathological fracture of the humerus caused by a JBC or ABC between 01.01.2001 and 31.12.2010, were investigated by chart review in four major paediatric trauma centres. Age, gender, fracture localisation, X-ray findings, treatment and outcome - assessed by the Capanna classification (I to IV), were analysed. 60 children [41male, 19 female; mean age: 9 years (4-14 years)] with 43 JBC and 12 ABC were included as well as five cysts, who could not be classified definitively. First treatment was non-operatively in 33 children. Of these 27 cysts did not improve; likewise the supportive installation of cortisone in six patients did not change the outcome. The first treatment consisted of elastic stable intramedullary in 13 children; up to three nail exchanges included. But only six of these reached (nearly) complete resolution (I/II). Overall the combined mechanical and biological treatment with curettage, elastic stable intramedullary nailing, (artificial) bone substitute and in some cases growth factors was performed as the 1st-line treatment in nine patients and further in 2nd or 3rd-line treatments in 13 humeral cysts. More than half of these reached a complete or nearly complete resolution of the cyst (12x I, 5x II, 1x III, 4x IV). Major complications in all operated patients were six nails not removable and two children with upper extremities length differences. Healing rates are low for non-operative treatment, elastic stable intramedullary nailing alone and by using cortisone for cysts resolution in pathological fractures of the humerus. Data support a combined mechanical and biological treatment with curettage, elastic stable intramedullary nailing, (artificial) bone substitute and the use of growth factors.