Aims: ACL lesion is one of the most frequent event in sport injuries. It is generally a complete lesion which does not evolve to a spontaneous healing. In particular, after non surgical treatment, ACL often repairs on PCL with a residual articular laxity. A healing response technique has been described to treat ACL incomplete tears in skeletally immature athletes. Our technique is based on microfractures next to the ACL femoral insertion to obtain a scar reinforcement thanks to the action of mes-enchymal stem cells.

Methods: The authors report their experience using the same surgical technique and rehabilitation protocol in patients selected by type of lesion, age and time from injury.

The authors selected for the study young-middle age active patients, with incomplete ACL lesion: 27 patients (mean age of 23 years) have been evaluated, inclusion criteria was Lachman test < 1 cm, negative Jerk test and a proximal partial tear of ACL on MRI. Before and after surgery the patients have been evaluated using KT1000, MRI, clinical examination and Lysholm score with a 3 years average follow up.

Results: Clinical examination showed a significative improvement in Lysholm score from 63 to 85 and a minor anterior tibial translation measured with KT1000 (from a mean difference between the two legs of 5 mm preoperatively to 2 mm postoperatively). In only one case the ACL didn’t seem to heal and was necessary the traditional reconstruction. MRI at one year pointed out a reparative healing in almost all cases.

Conclusions: according to these results the healing response procedure can restore a subjective and objective stability and knee function, with proper patient selection and strictly following the rehabilitation protocol despite of age and time of lesion.

Aims: Crosslinked acetabular inserts have been introduced as a solution to the wear related periacetabular osteolysis, caused by the polyethylene wear debris. Laboratory tests and simulators have demonstrated that crosslinked-polyethylene has a higher resistance to wear than conventional polyethylene. However, studies have shown early crack or degeneration of crosslinked inserts. Concerns still remain about the clinical performances of crosslinked inserts. Although questionable, the roentgenographic measurement of the wear of the cup represents an indicator of the performance of the implant. Early catastrophic failures of other inserts taught us that for new materials it is mandatory to conduct an accurate clinical surveillance. In this work the radiographic-evaluated linear wear of a group of cross-linked inserts is compared to that of a non-crosslinked inserts for the same socket at 5 years.

Methods: From 2000 to 2002 we implanted a series of cups in which crosslinked and conventional acetabular inserts were placed randomly. Patients from each group underwent radiographic assessment after implantation, at 3 and 6 months and then yearly. Radiographs were obtained using a digitalized image system, which allowed a computerized bi-dimensional measurement by a specially developed Auto-CAD program. 12 healthy and active patients (6 crosslinke – 6 conevtional UHMWPE) have been selected for measurement.

Results: No macroscopic signs of loosening, mobilization and osteolysis were detected. Despite an increased wear rate for the conventional insert, no statistically sig-nificant differences of the linear wear were detected at five years for the two groups.

Conclusions: Longer follow-up and larger case studies are needed for more definitive conclusions. Nevertheless, this preliminary study shows that crosslinked polyethylene in vivo at 5 years does not give early failures and that its linear wear in the short term does not differ from that of a conventional polyethylene. Several other factors, such as the number and dimension of the debris, which are not detected by roentgenographic measurements, might be taken into consideration. Moreover it has been hypothesized for the crosslinked polyethylene an early plastic deformation, with consequent penetration of the head without wearing, which could affect the measurement on plan radiographs. Despite these limitations, roentgenographic measurements are quick and easy to perform, and therefore might be useful for the clinical practice of the periodical evaluation of the implants.

The aim of hip revison surgery is to restore biomechanical parameters: rotation centre, muscle arm lever and leg length; homologous bone grafting is often necessary. It is possible to bioenhance grafts, resulting in better osteointegration speed and quality. We propose the use of our platelet gel protocol. Care was given to assess the cost-benefit rate of the method. We performed densitometric analysis of homologous bioenhanced grafts vs homologous grafts, with a specific acetabular bone loss indication, randomising two groups of patients (rct study). The “intention to treat” was to decide the benefit of the method in order to extend use to all patients. Densitometric analysis was implemented with radiographic analysis using a modified Cook’s scale. We used clinical scores, too. The clinical and plain radiographic results did not differ significantly between the two groups or with our historical group (7 years/23 implants, already published). The synthesis of all instruments used indicates that the use of bioenhanced bone is promising for enhanced osteointegration; however, the study group must be extended and observed for a longer time to achieve appropriate study power.