The role of autologous chondrocyte implantation in the treatment of symptomatic chondromalacia patellae.

PURPOSE: Chondromalacia patella is a distinct clinical entity of abnormal softening of the articular cartilage of the patella, which results in chronic retropatellar pain. Its aetiology is still unclear but the process is thought to be a due to trauma to superficial chondrocytes resulting in a proteolytic enzymic breakdown of the matrix. Our aim was to assess the effectiveness of autologous chondrocyte implantation on patients with a proven symptomatic retropatellar lesion who had at least one failed conventional marrow-stimulating therapy. METHODS: We performed chondrocyte implantation on 48 patients: 25 received autologous chondrocyte implantation with a type I/III membrane (ACI-C) method (Geistlich Biomaterials, Wolhusen, Switzerland), and 23 received the Matrix-assisted Chondrocyte Implantation (MACI) technique (Genzyme, Kastrup, Denmark). RESULTS: Over a mean follow-up period of 40.3 months, there was a statistically significant improvement in subjective pain scoring using the visual analogue scale (VAS) and objective functional scores using the Modified Cincinnati Rating System (MCS) in both groups. CONCLUSIONS: Chondromalacia patellae lesions responded well to chondrocyte implantation. Better results occurred with MACI than with ACI-C. Excellent and good results were achieved in 40% of ACI-C patients and 57% of MACI patients, but success of chondrocyte implantation was greater with medial/odd-facet lesions. Given that the MACI procedure is technically easier and less time consuming, we consider it to be useful for treating patients with symptomatic chondral defects secondary to chondromalacia patellae.

Bone remodeling around the tibial component of distal femoral expandable endoprosthesis.

Radiographs of 33 patients who had an expandable prosthesis inserted after tumor resection in the distal femur were evaluated. We hypothesized that, when a sleeve was present, there was greater stem migration and cortical reaction. The thickness of medial and lateral cortices of the tibia was measured at 6 months and on the last follow-up radiograph. The distance from the edge of the prosthesis to the cortical edge was also compared. When a sleeve was present, there was greater stem migration (P < .001) and a greater increase in lateral cortical thickness (P < .001). There was a higher revision rate when a sleeve was used, but this was not statistically significant. There was no difference in function according to the Toronto Extremity Salvage Score (TESS) between the 2 groups. This is the first study to demonstrate that the presence of a polyethylene sleeve is associated with a tendency for the tibial prosthesis to migrate laterally and cause a greater sclerotic reaction.

Long term results of the Corin C-Fit uncemented total hip arthroplasty in young patients.

INTRODUCTION: We conducted a prospective study to evaluate the long-term results after Corin C-Fit uncemented total hip arthroplasty in young patients with hydroxyapatite or porous coated components. MATERIALS AND METHODS: We prospectively followed 36 patients (38 hips) who had Corin C-Fit uncemented total hip arthroplasties by eight experienced consultant surgeons at two centres. The acetabular and femoral components were hydroxyapatite or porous coated. RESULTS: The overall 10-year survival rate for the Corin C-Fit arthroplasty was 43%. The 10-year survivorship for the femoral implant was 56% and for the acetabular component 59%. CONCLUSION: The evidence presented in this study suggests that the Corin C-Fit uncemented total hip arthroplasty has one of the highest mid- and long-term failure rates for both femoral and acetabular components in the literature. We believe this implant should not be used and patients who have had this form of total hip arthroplasty should be kept under regular review.

Clinical applications of mesenchymal stem cells in the treatment of fracture non-union and bone defects.

Bone defects resulting from trauma or resorption, whether physiological or pathological, remain a major challenge in the management of patients. The limits of bone regeneration still result in many people never recovering fully their function and quality of life; with all the social, financial and psychological implications. The aim of this review is to present the current level of possible applications of stem cells and tissue engineering in bone repair. From animal models to human trials, the knowledge surrounding the use of mesenchymal stem cells in manipulating bone healing, where normal physiological procedures have failed, are presented in chronological order. The possibilities in clinical applications of mesenchymal stem cells are evident and exciting. The efficacy, including long-term, of such treatment options still requires further knowledge and appropriately conducted clinical trials, with adequate patient numbers. Once these techniques are properly mastered and perfected, the benefits to regenerative medicine will be immense.

The potential therapeutic use of stem cells in cartilage repair.

As our population demographics change, osteoarthritis and cartilage defects are becoming more prevalent. The discovery of stems cells and their ability for indefinite regeneration has revolutionised the way cartilage problems are viewed. Tissue engineering has been shown to be the ideal way of repairing articular cartilage lesions, i.e. back to native tissue. Cartilage is an ideal tissue engineering target as it is avascular, aneural and alymphatic. The two main types of stem cells being investigated in chondrogenesis are embryological and mesenchymal stem cells. Research into embryological stem cells has been surrounded by controversy because of ethical, religious and social concerns. We discuss the use of embryological and mesenchymal stem cells in cartilage repair and the various factors involved in the differentiation into chondrocytes. We also discuss commonly used mesenchymal stem cell markers and their limitations.

Embryonic versus mesenchymal stem cells in cartilage repair.

As our population changes osteoarthritis and cartilage defects are becoming more prevalent. The discovery of stems cells and their ability for indefinite regeneration has revolutionised the way cartilage problems are viewed. Tissue engineering has been shown to be the ideal way of repairing articular cartilage lesions, i.e. back to native tissue. The two main types of stem cells being investigated in chondrogenesis are embryological and mesenchymal stem cells. Research into embryological stem cells has been surrounded by controversy because of tumour formation and damaging embryos during the harvest of cells. We discuss the use of embryological and mesenchymal stem cells in cartilage repair and the various factors involved in the differentiation into chondrocytes.

Treating stiffness after total knee arthroplasty: a technical note and preliminary results.

Total Knee Replacement is used to treat pain, stiffness and reduced range of movement. It has been estimated that a minimum of 90 degrees of range of motion in the knee is required for normal activities of daily living. In this article we demonstrate a technical note with a small patient series about the methods of treating knee stiffness after Total Knee Replacement.