We aimed to investigate the effect of Seprafilm®, a synthetic biomembran, on the intra-articular adhesion formation in an experimental arthrofibrosis model.

Twenty male white rabbits were randomly allocated into two groups of 10 animals in each. A standard surgical procedure aiming at the development of arthrofibrosis and including medial parapatellar arthrotomy, lateral eversion of the patella, partial synovectomy and debridement of anterior of supracondylar area and patella joint surface by scalpel was performed on all rabbits' right knees. Group 1 rabbits served as controls, and in Group 2 rabbits a Seprafilm®, barrier placed into the described area. In both groups, after surgery, knee joint was immobilized by a no.5 wire suture passing from the ankle and groin and keeping the joint in 140° of flexion. At 6th week, all animals were sacrificed and adhesion formation was evaluated both macroscopically and histo-pathologically. All data were semi-quantified and analyzed statistically by Fisher's exact test.

While all rabbits in control group displayed different rates of adhesion macroscopically (62.5% severe, 25% moderate, 12.5% mild), none in the study group had it. The average macroscopic adhesion score was 2.5 ± 0.75 in control group, and 0 in Seprafilm® group. Histopathologic evaluation also revealed microscopic adhesion in all rabbits in control group, but none in Seprafilm® group. Fibroblast proliferation in Seprafilm® group (100% mild) was significantly lower than in control group (62.5% severe, 37.5% moderate) (p<0.05).

In conclusion, use of Seprafilm® as a mechanical barrier may be of value against the formation of arthrofibrosis in risky knees such as septic and traumatic ones.

The purposes of this study were to determine whether it is necessary to obtain MRI of the knee prior to high tibial osteotomy (HTO) and to evaluate usefulness of MRI regarding its contributions on accurate diagnosing and changing possible indications for surgical intervention in patients on way to HTO.

Preoperative MRI of affected knee of 39 patients (23 female, 16 male) who had indication of HTO due to varus gonarthrosis were evaluated based on expected findings, possible findings and unexpected findings. The structural changes in bone (at femoral condyles, tibial platoes and patellae), meniscal abnormalities, ligamentous changes, the joint space width, osteophytes, subcondral cysts, baker cyst and joint effusion were evaluated. As expected, the most common and severe findings were observed at medial compartment in te majority of patients. For medial femoral condyl (MFC), subchondral sclerosis was seen in 22 patients (56.4%), osteonecrosis was seen in 9 patients (23.1%), bone marrow edema was seen in 4 patients (10.3%). Although there were less severe lesions, similar results were observed in the medial tibial plato (MTP) (51.3%, 17.9% and 7.7%, respectively). In the lateral compartments, the severity of lesions were higher than expected. A higher occurence rate of subchondral sclerosis (48.7%) was observed in patellae. Osteophytes were seen frequently in MFC (in all patients, median 3.8 mm). As expected, medial meniscus changes were observed in all patients. As an unexpected finding, periarticular enchondroma was seen in 2 of patients.

MRI is the most appropriate non-invasive method to examine joint structures, including the cartilage, menisci and synovial tissue that can be obtained with arthroscopy which is invasive and more costly tool. MRI appears to be particularly useful for preoperative evaluation of patients in preventation of unnessary meniscal surgical interventions. The finding of 30% lateral compartment changes observed on MRI, as in arthroscopy, is not an obstacle for indication of HTO.