Cartilage Grafting, Focal Resurfacing Implants and Meniscal Repair
DNB Orthopaedics • October 2023 • Paper IV • Question 9 • 10 Marks [3+3+4]
Introduction
Articular cartilage and menisci are critical for load transmission, joint congruity, lubrication and shock absorption. Because mature articular cartilage has limited intrinsic healing potential, focal cartilage defects may progress to pain, mechanical symptoms and eventually secondary osteoarthritis.
Modern joint-preservation surgery aims to restore the articular surface and preserve meniscal tissue wherever possible rather than proceeding directly to joint replacement.
Core exam principle: Treat the lesion, but also correct the environment — alignment, instability, meniscal deficiency and subchondral bone pathology must be addressed.
A. Cartilage Grafting [3 Marks]
Definition
Cartilage grafting refers to surgical transplantation or implantation of osteochondral tissue, chondrocytes or cartilage-restoration constructs into a focal articular cartilage defect with the aim of restoring a durable, congruent joint surface.
Why Articular Cartilage Heals Poorly
- Avascular
- Aneural
- Alymphatic
- Low cellular density
- Chondrocytes have limited proliferative capacity
Superficial chondral defects that do not penetrate the subchondral bone have very limited spontaneous healing. Defects that breach subchondral bone may fill with fibrocartilage, which is mechanically inferior to native hyaline cartilage.
Assessment of Cartilage Defects
Lesions are commonly graded…