The treatment of relapsing pseudoarthrosis of ulna presents quite a lot of perplexities as regards the surgical strategy to follow which means of synthesis to solve the biomechanical problems (lack of favourable loading stimuli and, on the contrary, presence of unfavourable torsional strengths due to the movement of pronosupination of the forearm),and how to interact in order to favour the restoration of osteogenesis (homologous or autologous bone graft, vascularized or not, bone substitutes, employment of autologous growth factors, of morphogenetic proteins (BMP),and of autologous staminal cells).

The authors report about 4 particular cases of relapsing pseudoarthrosis of the ulna previously treated with autologous bone grafts but with no recovery.

In order to activate osteogenesis, the authors have employed a graft of autologous bone enriched with platelet derived growth factors + adult mesenchymal stem cells from drawing from the iliac wing. The osteosyntesis has been carried out in 3 cases with endomidollar locked nail and, in one case, with external fixation.

All the four cases have reached prompt lasting clinical recovery (following up from 8 to 28 month) and Rx precocious evidence of osteointegration of the grafts independently from the synthesis means.

The limited casuistry does not enable us to report any comparable statistical data.

The authors think that association of AGF + adult mesenchymal stem cells can be determinant and encouraging and, thanks to the results, they suggest its spreading.

Haemophilia is a lifelong inherited bleeding disorder characterized by spontaneous bleeding resulting in painful joint deformities. Even if prosthetic surgery and the effectiveness and safety of clotting factor concentrate have improved the therapeutic options available, sometimes the orthopaedic surgeon has to treat substance losses. First, we have to distinguish: 1) sub-chondral cysts, 2) intra-osseous cysts, 3) pseudo-tumour (a chronic expanding blood cyst with the ability to displace and destroy adjacent tissues) Surgical treatment is in relation to its anatomical location and extension and is always associated with prolonged treatment with clotting factor concentrate. In our 20 years’ experience, we have used several therapeutic options. In some cases, we use filling with bone graft and fibrin seal and today platelet derived growth factor; in the others we have used amputation or custom made prosthesis.

From Urist’s studies (1965) to the following observations by Sampath and Reddi (1981) on the role of BPM morphogenetic protein and, more particularly, BPMs/ Ops in the complex mechanism of bone regeneration to recent studies (Solheim, 1998) on the properties of the single elements belonging to the superfamily of AGF of platlet derivation to activate the specific receptors of stem cells, considerable progress has been made in research and clinical application. The non-specificity of the present evaluation methods of patient outcome prevent us from singling out which element has activated the osteogenetic process, and when and which one has affected the course favourably.

In order to answer all these questions, we have carried out a prospective study between autologous AGF and stem cell application in orthopaedics and the ex vivo evaluation in vitro of platelet activation of osteoblasts. From March 2002 to January 2004, we treated 21 cases of osteolysis (in mobilisations due to pros-thesis of hip and knee, necrosis of bone head femur, pseudoarthrosis of the humerus and ulna, and aneurysmal relapsing cyst). The procedure consisted in using stem cells+AGF+autologous bone graft (two cases) or bank bone graft (13 cases)-or hydroxyapatite (two cases)+autologous fibrin glue and at the same time, in vitro culture of the patient’s osteoblasts+AGF. Among the AGF, PDGF is an important mitogenous factor. Among the isoforms of PDGF, the PDGF-AA and PDGF-AB are stored in alpha –granules and released when platelets are activated. PDGF-AA is preferentially secreted by osteoblasts and fibroblasts. PDGF-AA and PDGF-AB were measured in supernatants of osteoblasts in culture media, activated platelet culture media, osteoblasts plus activated platelet culture media at day 0, day +4, after adding platelet and day +8. At the end a cytological test was performed. The study has proved that the PDGF-AA increases remarkably after adding platelet gel to the osteoblasts, more than in control cultures which are lacking in platelet gel, which might mean the platlets activate the osteoblast and activate the osteogenetic process.

The use of autologous fibrin glue enriched in AGF has demonstrated a better recovery of the tissue scar, as well as emathic save and better stop of grafts. The range of cases is not homogeneous and prevents us from drawing any statistical conclusions, but the quick bone recovery leads to great satisfaction both for patients and their physicians.

Limb lengthening is used to correct leg length discrepancy and to increase stature. The reported frequency of peripheral nerve complications varies from 5% to 30%, but is probably underestimated. Damage may be direct or be caused by overstretching of the nerves. We have used electrophysiological tests to evaluate five patients during bilateral tibial lengthening by the Ilizarov method. Results after 24 to 107 days of lengthening showed electromyographic evidence of partial muscle denervation in all 10 limbs, with reduced motor conduction velocities in two tibial nerves and three common peroneal nerves. The sensory conduction velocity in the sural nerve was always unchanged. A clear relationship was shown between the amount of tibial lengthening and the degree of electrophysiological abnormality. Our results suggest that subclinical nerve damage is a very frequent complication of tibial lengthening.