Juvenile bone cysts in children and adolescents are often discovered incidentally or in connection with a pathologic fracture. Although the diagnostic procedure in this type of lesion affecting the skeleton has become uniform, the treatment varies according to the principles established at different clinics. The aim of our study was to compare two Methods: applied in the treatment of juvenile bone cysts, i.e. the established method of a series of Methylprednisolone injections and a new mini-invasive method using a Tricalcium phosphate.

In both groups of patients, we performed an evaluation of the number of required surgeries, general anaesthesias and subsequent hospitalizations (including the length of hospitalization), the treatment results and the interval between surgery and complete cyst healing using Neer’s evaluation criteria. The group of patients treated with Methylprednisolone consisted of 24 patients and the group of patients treated with Tricalcium phosphate comprised 20 patients.

The outcome of the statistical analysis proves that in patients treated with Tricalcium phosphate significantly better results were obtained compared to patients where Methylprednisolone was applied. A subsequent surgery (additional application) was necessary only in two Tricalcium phosphate patients (10%) compared to nineteen Methylprednisolone patients (79%). The average length of hospitalization was 4 days in Tricalcium phosphate patients and 3.5 days in Methylprednisolone patients. Excellent and good results according to the Neer classification were documented in eighteen Tricalcium phosphate patients (19%) and in twelve Methylprednisolone patients (50%).

The treatment of juvenile bone cysts with a biocompatible resorbable synthetic filler Tricalcium phosphate helps reduce the number of surgeries necessary for complete cyst healing and produces better results in terms of Neer’s evaluation criteria of bone cyst treatment results compared to the application of Methylprednisolone into the cyst.

This work was supported by the Internal Grant Agency of the Ministry of Health of the Czech Republic (NS9860-3/2008).

Objective: Assorted treatment methods of articular cartilage injury are known. The using of allogenic MSCs (Mesenchymal stem cells) get from bone marrow blood brings combinated with new composite collagen/chi-tosan scaffold new possibilities in treatment of these defects. The aim of our study was to examine the therapeutic effect of this transplantation.

Methods: Experimental group A (20 miniatuture pigs), allogenic MSCs in composite scaffold were transplanted into a iatrogenic defect on articular cartilage of lateral condyle of left distal femur. Control group B (20 miniatuture pigs), only composite scaffold were transplanted into a iatrogenic defect on articular cartilage in the same place. The finally results in both groups were by histological examination (H-E, PAS, ELISA, FISH – MSCs was with labeled fluorochrome CM-DiI) determinated. For objective evaluation we used the histological - histochemical O’Driscoll score.

Results: In group A the ‘Driscoll score (quality of cartilage healing) was 16,3±2,2, in group B 10,0±1,56. Imunohistochemical examination the collagen II fibres detected in group A in 80%, FISH detected fluorochrome CM-DiI in 75% in new cartilage.

Conclusion: MSCs transplantation leads to much better resluts of healing compared with untreated defects in control group (only scaffold transplnatation). Supported by the Research Projects of MSMT (NPV II 2B06130).