[Spontaneous remission of osteochondritis dissecans in 8 pediatric patients undergoing conservative treatment]

Abstract

Purpose: Ostheocondritis dissecans lesions of the knee has a poor prognosis if certain signs are present at MRI. Clinical course is dependent on the site and extension of the lesions, and the age of the patient. In children, certain MRI findings similar to those found in the adult have a different prognostic significance, and in some case the condition can be cured by conservative treatment. By means of MR follow-up examinations performed at 6, 12 months, and in 2 cases, 24 months, we evaluated up the evolution of 8 osteochondritis dissecans treated conservatively with rest and antinflammatory drugs.

Material and methods: 7 pediatric patients (mean age 13 years) with 8 lesions of osteochondritis dissecans (bilateral in one cases) underwent MR follow-up examinations. In all cases the maximum longitudinal diameter of the lesion focus did not exceed 2 cm and at the first MR control the cartilage was intact. The MR examinations were performed using a dedicated low field magnet and a permanent low field magnet.

Results: MR allowed us to correctly identify both the origin and the extent of the lesion in all the patients. The follow-up examinations performed after 6, 12 and 24 months, showed complete disappearance of the osteochondritis dissecans focus in 6 cases whereas two lesions showed a 50% reduction of their extent.

Discussion and conclusions: Magnetic Resonance currently represents the gold standard for the evaluation of osteochondritis dissecans focus because, unlike other imaging techniques which are not able to identify the lesion it enables to establish an early diagnosis. Although the small number of the lesions examined only allows preliminary conclusions to be drawn, we have shown that in pediatric patients conservatively treated osteochondral lesions may evolve favourably. However, in all the cases examined the cartilage covering the lesion was intact. Favourable prognostic factors at MR are: stability of the transchondrial fragment and infraspongious edema at the adjacent bone. Peripheral hypervascularization may represent an attempt and spontaneous heading, as occurred in our cases.