Introduction: This research aims to study the efficacy and effect of Bone Marrow Stromal Stem Cell (BMSSC) implantation on healing of refractory fracture non-union.

Methods: Approved by the local Ethics Committee, twelve patients (9M and 3F), age range 38 to 76 years (mean 49.9) with non-union resistant to multiple previous attempts of treatment (mean 3.75 procedures) were treated. Four tibial and eight femoral non-union.

The patients were admitted for harvesting of stromal stem cells by bone marrow aspiration from the iliac bone. BMSSC were expanded in tissue cultures for three weeks to an average of 5 x 10⁶ cells. After successful culture the non-union site underwent decortication and BMSSC added to synthetic bone substitute (different types) on one side of the fracture (medial or lateral) according to randomisation. The side of treatment was blinded to patient, surgeons and radiologist.

Standard radiographs were taken and evaluated independently by three experienced musculoskeletal radiologists. The extent of callus formation on each side was recorded. In equivocal cases computerized tomography (CT) was also obtained.

Results: No patient developed systemic complications related to the procedure. On follow-up callus formation was present in 9 of 12 patients. Callus was more marked on the cell implantation side in 6/12 patients (50%), control side in 1/12 (8.3%) and on both sides in 2 patients. 3 patients showed no change.

Discussion: These findings suggest that implantation of BMSSC can enhance bone formation in persistent non-union. A larger randomized controlled trial will follow to test this new treatment.

Successful healing of a nine-year tibial nonunion resistant to six previous surgical procedures was achieved by tissue engineering. We used autologous bone marrow stromal cells (BMSCs) expanded to 5 × 10⁶ cells after three weeks’ tissue culture. Calcium sulphate (CaSO₄) in pellet form was combined with these cells at operation. The nonunion was clinically and radiologically healed two months after implantation.

This is the description of on healing of a long-standing tibial nonunion by tissue engineering. The successful combination of BMSCs and CaSO₄ has not to our knowledge been reported in a clinical setting.

Tissue engineering is an increasingly popular method of addressing pathological disorders of cartilage. Recent studies have demonstrated its clinical efficacy, but there is little information on the structural organisation and biochemical composition of the repair tissue and its relation to the adjacent normal tissue. We therefore analysed by polarised light microscopy and immunohistochemistry biopsies of repair tissue which had been taken 12 months after implantation of autologous chondrocytes in two patients with defects of articular cartilage.

Our findings showed zonal heterogeneity throughout the repair tissue. The deeper zone resembled hyaline-like articular cartilage whereas the upper zone was more fibrocartilaginous. The results indicate that within 12 months autologous chondrocyte implantation successfully produces replacement cartilage tissue, a major part of which resembles normal hyaline cartilage.