Alessandro Rozim Zorzi

Opening‐Wedge High Tibial Osteotomy With and Without Bone Graft

Medial opening-wedge has gained popularity in comparison to other techniques of high tibial osteotomy. This technique involves the creation of a gap in the tibia. Filling the gap with autologous iliac bone graft was recommended in the classic description, to prevent complications such as correction loss or delayed bone union. No previous reports have compared grafted and nongrafted osteotomies. This study hypothesized that the use of autologous bone graft in medial opening-wedge high tibial osteotomy (MOWHTO) less than 12.5 mm is unnecessary. A prospective randomized clinical trial was conducted. Forty-six opening-wedge high tibial osteotomies were carried out between April 2007 and December 2008. All had fixation with a type of Puddu stainless steel plate and screws. Patients were randomly divided by software analysis into two groups: group A had osteotomies that were filled with autologous bone graft and group B had osteotomies that were unfilled. Autologous iliac bone graft was harvested in both groups. Clinical and radiographic evaluations were performed twice monthly by blinded investigators. The rates of complications were compared between the groups. There was no difference in demographic data. Mean time to clinical bone union in group A was 12.4 weeks (confidence interval [CI] 11.2-13.6) and in group B was 13.7 weeks (CI 12.5-14.9), but this difference was not significant (P = 0.13). Signals of correction loss occurred in one patient (4.35%) in group A, and in two patients (8.70%) in group B. All osteotomies had achieved bone union. It was concluded that time to bone union was not statistically different between the group with bone graft and the group without graft.

Opening-wedge High Tibial Osteotomy With And Without Bone Graft.

Medial opening-wedge has gained popularity in comparison to other techniques of high tibial osteotomy. This technique involves the creation of a gap in the tibia. Filling the gap with autologous iliac bone graft was recommended in the classic description, to prevent complications such as correction loss or delayed bone union. No previous reports have compared grafted and nongrafted osteotomies. This study hypothesized that the use of autologous bone graft in medial opening-wedge high tibial osteotomy (MOWHTO) less than 12.5 mm is unnecessary. A prospective randomized clinical trial was conducted. Forty-six opening-wedge high tibial osteotomies were carried out between April 2007 and December 2008. All had fixation with a type of Puddu stainless steel plate and screws. Patients were randomly divided by software analysis into two groups: group A had osteotomies that were filled with autologous bone graft and group B had osteotomies that were unfilled. Autologous iliac bone graft was harvested in both groups. Clinical and radiographic evaluations were performed twice monthly by blinded investigators. The rates of complications were compared between the groups. There was no difference in demographic data. Mean time to clinical bone union in group A was 12.4 weeks (confidence interval [CI] 11.2-13.6) and in group B was 13.7 weeks (CI 12.5-14.9), but this difference was not significant (P = 0.13). Signals of correction loss occurred in one patient (4.35%) in group A, and in two patients (8.70%) in group B. All osteotomies had achieved bone union. It was concluded that time to bone union was not statistically different between the group with bone graft and the group without graft.

Effect of Human Adipose Tissue Mesenchymal Stem Cells on the Regeneration of Ovine Articular Cartilage

Cell therapy is a promising approach to improve cartilage healing. Adipose tissue is an abundant and readily accessible cell source. Previous studies have demonstrated good cartilage repair results with adipose tissue mesenchymal stem cells in small animal experiments. This study aimed to examine these cells in a large animal model. Thirty knees of adult sheep were randomly allocated to three treatment groups: CELLS (scaffold seeded with human adipose tissue mesenchymal stem cells), SCAFFOLD (scaffold without cells), or EMPTY (untreated lesions). A partial thickness defect was created in the medial femoral condyle. After six months, the knees were examined according to an adaptation of the International Cartilage Repair Society (ICRS 1) score, in addition to a new Partial Thickness Model scale and the ICRS macroscopic score. All of the animals completed the follow-up period. The CELLS group presented with the highest ICRS 1 score (8.3 ± 3.1), followed by the SCAFFOLD group (5.6 ± 2.2) and the EMPTY group (5.2 ± 2.4) (p = 0.033). Other scores were not significantly different. These results suggest that human adipose tissue mesenchymal stem cells promoted satisfactory cartilage repair in the ovine model.

Natural Type II Collagen Hydrogel, Fibrin Sealant, and Adipose-Derived Stem Cells as a Promising Combination for Articular Cartilage Repair

Objective Articular cartilage is an avascular tissue with limited ability of self-regeneration and the current clinical treatments have restricted capacity to restore damages induced by trauma or diseases. Therefore, new techniques are being tested for cartilage repair, using scaffolds and/or stem cells. Although type II collagen hydrogel, fibrin sealant, and adipose-derived stem cells (ASCs) represent suitable alternatives for cartilage formation, their combination has not yet been investigated in vivo for focal articular cartilage defects. We performed a simple experimental procedure using the combination of these 3 compounds on cartilage lesions of rabbit knees. Design The hydrogel was developed in house and was first tested in vitro for chondrogenic differentiation. Next, implants were performed in chondral defects with or without ASCs and the degree of regeneration was macroscopically and microscopically evaluated. Results Production of proteoglycans and the increased expression of collagen type II (COL2α1), aggrecan (ACAN), and sex-determining region Y-box 9 (SOX9) confirmed the chondrogenic character of ASCs in the hydrogel in vitro. Importantly, the addition of ASC induced a higher overall repair of the chondral lesions and a better cellular organization and collagen fiber alignment compared with the same treatment without ASCs. This regenerating tissue also presented the expression of cartilage glycosaminoglycan and type II collagen. Conclusions Our results indicate that the combination of the 3 compounds is effective for articular cartilage repair and may be of future clinical interest.

Modificações biomecânicas na marcha de indivíduos com osteoartrite medial do joelho

Objective Demonstrate the presence and magnitude of biomechanical variables during gait in patients with medial knee osteoarthritis (OA) and the relationship with the knee loading. Methods Gait of 21 subjects diagnosed with medial knee OA was evaluated and compared to the control group. Results The group with OA showed: Lower gait speed (0.8 ± 0.1 vs. 1.1 ± 0.1m/s), higher peak early (2.6 ± 1.2 vs. 0.3 ± 1.4 Nm/Kg) and late peak of the adduction moment (1.8 ± 0.7 vs. 0.9 ± 0.2 Nm/Kg), higher peak flexor moment (1.6 ± 0.9 vs. 0.6 ± 0.4 Nm/Kg), high dynamic peak varus (11.5º ± 8.3 vs. 3º ± 3.9), higher peak flexion (15.6º ± 8 vs. 9.3º to ± 4.1), with a flexion tendency (5.5º ± 8.5) in the stance phase, smaller peak of flexion (58.7º ± 13.3 vs. 67.5º ± 4.8) in the balance phase and higher peaks of external rotation (25.5º ± 12.7 vs. 0.5º ± 22.4). Conclusion Patients with medial knee OA show changes in gait with increased external rotation, speed reduction, increased flexor moment and flexion in the stance phase, insufficient for reduction of the load. Level of Evidence III, Case Control Study.OBJETIVE: Demonstrate the presence and magnitude of biomechanical variables during gait in patients with medial knee osteoarthritis (OA) and the relationship with the knee loading. METHODS: Gait of 21 subjects diagnosed with medial knee OA was evaluated and compared to the control group. RESULTS: The group with OA showed: Lower gait speed (0.8 ± 0.1 vs. 1.1 ± 0.1m/s), higher peak early (2.6 ± 1.2 vs. 0.3 ± 1.4 Nm/Kg) and late peak of the adduction moment (1.8 ± 0.7 vs. 0.9 ± 0.2 Nm/Kg), higher peak flexor moment (1.6 ± 0.9 vs. 0.6 ± 0.4 Nm/Kg) , high dynamic peak varus (11.5 ± 8.3 vs. 3o ± 3.9), higher peak flexion (15.6o ± 8 vs. 9.3o to ± 4.1), with a flexion tendency (5.5 o ± 8.5) in the stance phase, smaller peak of flexion (58.7o ± 13.3 vs. 67.5 o ± 4.8) in the balance phase and and higher peaks of external rotation (25.5o ± 12.7 vs. 0.5o ± 22.4). CONCLUSION: Patients with medial knee OA show changes in gait with increased external rotation, speed reduction, increased flexor moment and flexion in the stance phase, insufficient for reduction of the load. Level of Evidence III, Case Control Study.

A New Histological Scoring System for Partial Thickness Chondral Lesions

Despite the large number of papers about regeneration of articular cartilage, the good results achieved in small animals are not replicated in large animal models and in humans. One possible reason is the frequent use of the osteochondral model, with perforation of the subchondral bone plate. As the most frequent pattern of lesion in humans is the Partial Thickness, new therapies should be tested in this model. However, there is not a tool to evaluate the results of Partial Thickness model.Objective: to develop a new histological scoring system to be used in the Partial Thickness model of cartilage repair. Results: this paper describes in detail the new scoring system. It was divided in three main sections: repair tissue inside the lesion, cartilage around the lesion and degenerative changes in the base of the lesion.

Comparison of Puddu osteotomy with or without autologous bone grafting: a prospective clinical trial

Objectives To test the hypothesis that autologous iliac bone grafts do not enhance clinical results and do not decrease complication rates in patients undergoing medial opening-wedge high tibial osteotomy. Methods Forty patients allocated in a randomized, two-armed, double-blinded clinical trial were evaluated between 2007 and 2010. One group received bone graft, and the other group was left without filling the osteotomy defect. The primary outcome was the Knee Society Score. Radiographic measurement of the frontal anatomical femoral-tibial angle and the progression of osteoarthritis according to the modified Ahlback classification were used as secondary outcomes. Results There was no difference in KSS scale between the graft group (64.4 ± 21.8) and the graftless group (61.6 ± 17.3; p = 0.309). There was no difference of angle between the femur and tibia in the frontal plane between the groups (graft = 184 ± 4.6 degrees, graftless = 183.4 ± 5.1 degrees; p = 1.0), indicating that there is no loss of correction due to the lack of the graft. There was significant aggravation of osteoarthritis in a greater number of patients in a graft group (p = 0.005). Conclusion Autologous iliac bone graft does not improve clinical outcomes in medium and long-term follow-up of medial opening-wedge high tibial osteotomy fixed with a first generation Puddu plate in the conditions of this study.

Keblish's lateral surgical approach enhances patellar tilt in valgus knee arthroplasty☆

Objective To compare the clinical and radiological outcomes of conventional medial and lateral approaches for total knee replacement in the valgus osteoarthritic knee. Methods In this randomized controlled trial, 21 patients with valgus knee osteoarthritis were randomized to total knee replacement through medial or lateral approach. The primary outcome was radiographic patellar tilt. Secondary outcomes were visual analog scale of pain, postoperative levels of hemoglobin, and clinical aspect of the operative wound. Results There were no differences between the groups regarding other clinical variables. Mean lateral tilt of the patella was 3.1 degrees (SD ± 5.3) in the lateral approach group and 18 degrees (SD ± 10.2) in the medial approach group (p = 0.02). There were no differences regarding the secondary outcomes. Conclusion Lateral approach provided better patellar tilt following total knee replacement in valgus osteoarthritic knee.