Aim

Ultrahigh molecular weight polyethylene (UHMWPE) has been used for many years as a bearing surface in total joint replacement (TJR). However, late-state failure in TJR is predominantly caused by osteolysis mediated by wear particles. We tested our hypothesis that UHMWPE nanoparticles are important determinants in activating dendritic cells (DCs).

The distal femur fracture is a difficult injury that affects young men andelderly women. The tissue stripping that occurs with the traditional approach has been a factor in the development of complications like infection and nonunion. This study addresses the issue of minimally invasive approach. Does the LISS system really improve the results of such fracture?

Fifty-two patients were included in the trial from six academic trauma centres. Twenty-eight fractures had been randomised to be fixed with the LISS device, while twenty-four had the DCS implant. Type C3 fractures were excluded as they were not amenable for fixation with DCS system. All procedures were performed via minimally invasive technique. The LISS system had the targeter that helped with plate insertion and distal diaphyseal screws placement. Radiography was utilised in the case of the DCS distal screws insertion.

All fractures went onto union, except two participants in LISS group who had to be revised due to loss of reduction, in the early post-operative peroid. There were three nonunions in the same group. These required a re-operation. Further more, a LISS participant who had re-injured his distal femur (unrelated to LISS plate), was fixed with different implant. There was a single nonunion with the DCS group that needed revision surgery. There was one participant from each group who had drifted into varus. Neither required a re-operation. This translated into a 21% re-operation rate in the LISS system compared to 4% with the DCS device.

Our data supports the use of the DCS system in the fixation of distal femur fractures (except Type C3} via a minimally invasive approach. The LISS implant seems to be technique dependent. In our centre, the LISS plate had been discontinued in favour of the DCP and LCP systems.

Introduction

Intra-articular (IA) injections of corticosteroids and hyaluronic acid (HA) products are used to treat patients with knee osteoarthritis pain that has not responded to more conservative treatment. Corticosteroids are a standard of care despite only suggestive clinical evidence of 12 or more weeks of pain relief. However the duration of pain relief with this treatment appears to be short and not a long term solution.

Introduction

The precise indications for tibial component metal backing and modularity remain controversial in routine primary total knee arthroplasty. This is particularly true in elderly patients where the perceived benefits of metal backing such as load redistribution and the reduction of polyethylene strain may be clinically less relevant. The cost implications for choosing a metal-backed design over an all-polyethylene design may exceed USD500 per primary knee arthroplasty case.

A tissue engineering-based approach has become a possible solution for the treatment of chondral lesions. Actually, autologous chondrocytes seeded on biodegradable scaffolds for cell proliferation were successfully developed. However, these techniques promote cartilaginous but not bony regeneration. Therefore a new experimental approach involving mesenchymal stem cells (MSC) has been introduced.

A 31-year-old man affected by massive osteonecrosis of the right femoral head was selected to begin this study. The MSC were isolated from the bone marrow harvested from the patient’s iliac crest. After a 3-week monolayer expansion, cells were seeded and cultured onto hyaluronan-based three-dimensional scaffolds and DBM spongy chips, used to regenerate the cartilaginous and the bony portion, respectively. After a 2-week cultivation, constructs were implanted inside the osteochondral defect using the transtrochanteric approach under arthroscopic control. The patient underwent clinical, X-ray and MRI control during the first 6 months after operation.

Pluripotent MSC may be a promising strategy for osteochondral defect reconstruction due to their capacity to differentiate in vivo along chondrocytic and osteoblastic lineages. This ability, combined with two different kinds of three-dimensional scaffolds, permits simultaneous bone and cartilage tissue regeneration. The preliminary results are encouraging but a more precise judgement of the effectiveness of this method requires longer follow-up.

Aims:Short-term results of lateral closing wedge high tibial osteotomy (CWO) is satisfactory in 80–90% of patients but the results of CWO shows steady decline over time. We evaluated results of osteotomies to determine survivorship and to identify risk factors associated with survival of the osteotomies.

Methods:Between 01.01.1986. and 31.12.1991. 113 patients have undergone CWO. We could evaluated 54 patients (31 men and 23 women) with 58 operations. The average age at operation was 57.6 (31–69) years and the mean follow-up was 12.2 (10–15) years.

The probability of failure was estimated as a function of time, with use of the Life-table survivorship method.

The linear correlation, uni and multivariate Stepwise regression method were used for statistical analysis. Results:Using the Life-table survivorship estimate of failure, the probability of survival for CWO was 91.3% at 5 years and 72.5% at 10 years.

An age, preoperative varus deformity and range of movement have not inßuenced long term survivorship (linear correlation).

Uni and multivariate Stepwise regression showed, that overweight, grade III chondromalacia in medial compartment, previous menisectomy and insufþcient valgus correction (FTA< 170¡) were signiþcantly associated with early failure.

Conclusions:Analysis of risk factors suggests that careful patient selection can improve long term survivorship of CWO.

Aims: Metatarsus osteotomies usually require an internal metal þxation in order to achieve the required stability. Taking the metal out means an operation. This is unpleasant for the patients by all means. Absorbing screws are rather expensive. The authors used an absorbing polydioxanone thread in case of osteotomies. Methods: þxation by absorbing thread has been used in three types of operations: A: chevron osteotomia Hallux valgus/metatarsus primus varus/, B: Weil osteotomia II-III-IV metatarsalgias, C: Assimetricus ÔVñ osteotomia II III-IV metatarsalgias. In all the cases mentioned above a polydioxanone thread has been used. Altogether 62 operations have been carried out, 27 in case of A, 19 in case of B, and 16 in case of C. The patients received full burden 2 weeks after the operation, just like in case of þxation with a metal screw. Follow-up examination was done 1, 3 and 6 months after the operation. Rtg examination was done immediately in postoperative time and following a 3-month interval. Results: during follow-up examination no symptoms revealing the tear of thread have been observed. In the measures of the consolidation of bones no difference between the two methods has been revealed. Conclusions: þxation by absorbing thread is a perfect alternative of that by metal screws. The patients have a positive opinion about not having to undergo another operation. This method does not make the operation more expensive.