Resection-Induced Leveling of Elevated Plug Cartilage in Osteochondral Autologous Transplantation of the Knee Achieves Acceptable Clinical Results

Surface morphology of osteochondral grafts harvested from femoral condyles with free-hand technique: a cadaveric study

PURPOSE

The purpose of this cadaver study was to examine the surface morphology of the osteochondral grafts harvested from the femoral condyles using the free-hand graft harvesting technique.

MATERIALS AND METHODS

One hundred osteochondral grafts were harvested with 6.5 mm chisels at ten different donor sites using the free-hand technique in five paired knee specimens (Mean age: 56.4 years). The cartilage and subchondral bone surface angles were measured through multiplanar reconstruction computerized tomography examination. The cartilage thickness was measured with a MicroScribe G2X digitizer with an accuracy of 0.02 mm. An acceptable congruity could be obtained when these plugs were transferred to a perpendicular socket (articular step-off of less than 1 mm and 0.5 mm) was evaluated.

RESULTS

Four plugs were damaged or broken during harvesting due to technical difficulties; thus remaining 96 plugs were analyzed. The cartilage thickness varied between 1.36 mm and 3.26 mm across the donor sites. The cartilage was the thinnest in the medial intercondylar notch and thickest in the lateral supracondylar notch. Twenty of ninety-six plugs (20.8%) had unacceptable cartilage surface inclination according to the > 0.5 mm protrusion criteria. Of these plugs, 14 were harvested from the lateral intercondylar notch, whereas five of 96 plugs (5.2%) had unacceptable cartilage surface inclination according to the > 1 mm protrusion criteria. Of these plugs, all were harvested from the lateral intercondylar notch.

CONCLUSIONS

High rates of unacceptable plugs (up to 100%) might be harvested from the lateral intercondylar notch. In large chondral lesions that require multiple plugs, lateral and medial supracondylar ridges were the best donor sites for perpendicular plug harvesting, whereas lateral intercondylar notch should be avoided.

Long-Term Survivorship and Clinical Outcomes of Osteochondral Autologous Transplantation for Steroid-Induced Osteonecrosis of the Knee

OBJECTIVE

Treatments for steroid-induced osteonecrosis of the knee remains challenging, and there has not been sufficient evidence to support joint preservation surgery. This study evaluated long-term outcomes of osteochondral autologous transplantation (OAT) for steroid-induced osteonecrosis of the knee.

DESIGN

This retrospective case series included patients who underwent OAT for steroid-induced osteonecrosis of the knee from 1998 to 2008. The survivorship and need for secondary surgery were evaluated, and the clinical outcome was evaluated with the International Knee Documentation Committee (IKDC) subjective score. Preoperative and final Kellgren-Lawrence (KL) grade of the femorotibial and patellofemoral joints were individually evaluated.

RESULTS

Fourteen knees of 10 patients whose mean age was 32.5 (95%CI 26.4-38.6) years were included and followed for 14.0 (12.4-15.7) years. The mean lesion size of 6.9 (5.3-8.5) cm² was repaired using 4 median (minimum 2, maximum 5) osteochondral plugs. No revision surgeries were performed for transplanted osteochondral plugs. The IKDC subjective score improved from 32.9 (24.5-41.3) to 74.2 (61.9-88.5) (P < 0.001). Knee flexion was improved at the final follow-up, and Seiza sitting was finally possible in 9 knees in 7 patients. Although the osteoarthritic change did not progress in femorotibial joint, patellofemoral joint showed early osteoarthritic changes at the final follow-up (mean KL grade: 0.8 [0.5-1.1]).

CONCLUSIONS

Prosthetic joint replacement was successfully avoided for at least the first decade by OAT in young patients with steroid-induced osteonecrosis of the knee. The progression of KL grade of the patellofemoral joint is of concern.

Decellularized cartilage as a prospective scaffold for cartilage repair

Articular cartilage lacks self-healing capacity, and there is no effective therapy facilitating cartilage repair. Osteoarthritis (OA) due to cartilage defects represents large and increasing healthcare burdens worldwide. Nowadays, the generation of scaffolds to preserve bioactive factors and the biophysical environment has received increasing attention. Furthermore, improved decellularization technology has provided novel insights into OA treatment. This review provides a comparative account of different cartilage defect therapies. Furthermore, some recent effective decellularization protocols have been discussed. In particular, this review focuses on the decellularization ratio of each protocol. Moreover, these protocols were compared particularly on the basis of immunogenicity and mechanical functionality. Further, various recellularization methods have been enlisted and the reparative capacity of decellularized cartilage scaffolds is evaluated herein. The advantages and limitations of different recellularization processes have been described herein. This provides a basis for the generation of decellularized cartilage scaffolds, thereby potentially promoting the possibility of decellularization as a clinical therapeutic target.