2025 ISAKOS Biennial Congress ePoster
Reduction Of Subcondral Bone Cyst Formation And Sclerosis Associated With Microfractures By A Polydioxanone Scaffold Compared With A Collagen-Based Membrane In A Sheep Model
Pedro Debieux, MD, PhD, São Paulo, SP BRAZIL
Camila Cohen Kaleka, PhD, São Paulo, SP BRAZIL
Moises Cohen, MD, PhD, Prof., São Paulo, SP BRAZIL
Emanuel Vitor Pereira Apolonio, DVM MS, Botucatu, São Paulo BRAZIL
Vittoria Guerra Altheman, Msc, Botucatu, São paulo BRAZIL
Gustavo Guadalupe, MD, São Paulo BRAZIL
Ana Liz Garcia Alves, PhD, Botucatu, SAO PAULO BRAZIL
Hospital Israelita Albert Einstein / São Paulo State University (UNESP), São Paulo, SP, BRAZIL
FDA Status Cleared
Summary
This study found that while microfracturing commonly leads to subchondral bone cysts and sclerosis, the use of a polydioxanone membrane in sheep reduces the formation of these cysts and decreases sclerosis compared to both microfracture alone and a collagen membrane.
ePosters will be available shortly before Congress
Abstract
Purpose
Despite new products and surgical techniques for cartilage repair, bone marrow stimulation (BMS) with microfracturing remains the most commonly performed procedure for cartilage repair. However, the lesions caused in the subcondral bone (SCB) lead to morphological changes, especially SCB cysts, and sclerosis, which correlate with the success rate of cartilage repair. Our proposal is to study SCB cyst formation and sclerosis after microfracturing with a polydioxanone membrane compared with a commercial porcine collagen (type I/III) in a sheep model. Material & Methods: Chondral defects 10 mm in diameter were created in the weight-bearing center of the medial femoral condyle in both pelvic limbs of 16 adult Ile de France sheep. For microfracturing, 5 holes were drilled into the cartilage defect with 1.5 mm burs. The included animals were divided into four groups of 8 knees: (1- MFG) microfracture only, (2- COLG) microfracture with type I/III collagen membrane, (3- PDOG) microfracture with polydioxanone scaffold, (4- CG) control group without treatment. After 26 weeks, the knees were scanned by computed tomography to detect cyst formation, and bone densitometry was performed using Image J software to assess SCB sclerosis. The normal value of bone density measurement was determined on the unoperated lateral condyle of the femur. Results: Cysts were characterized as a well-demarcated circular area with a radiolucent characteristic and sclerotic margin in the subchondral bone. CG had a cyst in 1 knee, MFG and COLG in all 8 knees, while PDOG had a cyst in 4 knees. In all groups, bone density was significantly (P ≤ 0,05) increased after chondral and osteochondral defects, but the mean values were lower in COLG and PDOG. Conclusion: Our results show that microfracturing technique in sheep promotes cyst formation, while the polydioxanone membrane has a protective effect and can reduce SCB cyst formation and sclerosis.