Chapter 5 Debridement, Microfracture, and Osteochondral Autograft Transfer for Treatment of Cartilage Defects

Andreas H. Gomoll, MD, Tom Minas, MD, MS

Introduction

All three techniques discussed in this chapter are considered first-line treatment options for articular cartilage defects, predominately because of their low invasiveness. Debridement is mostly indicated for treatment of (1) incidental lesions discovered during surgery directed at other joint pathology, such as meniscectomy and anterior cruciate ligament reconstruction, and (2) lesions in lower-demand patients who are reluctant to undergo other cartilage repair procedures that are more invasive and/or require long rehabilitation. Debridement is also a good initial treatment option for lesions that are deemed borderline or too large for microfracture or osteochondral autograft transfer (OAT) because it does not appear to compromise later treatment with autologous chondrocyte implantation.

Microfracture is a minimally invasive option whose indications have been refined in the last few years through multiple investigations. It has a high success rate when used appropriately for the treatment of small (<2–4 cm²) defects in the femoral condyles of younger (<35–40 years) patients with acute defects.¹ Larger defects and those located in the patellofemoral joint deteriorate after 24 to 36 months.²

OAT is generally indicated for treatment of small (<2–4 cm²) defects in the femoral condyles and trochlea but not in the patella.³ The recommendation for size is based on the limited availability of cartilage elsewhere in the knee (donor site morbidity) and on the ability to minimize the complication of plug necrosis, which is seen more frequently in central plugs that are completely surrounded by other plugs and therefore have no direct contact to native bone for integration. Although lesions up to 4 cm² have been indicated for OAT, it is our preference to use this technique as first-line treatment for active, fit individuals with lesions 1 to 1.5 cm² because OAT does not cause donor site symptoms in patients with these small lesions and results in a rapid return to sport (4–8 months) with a mature hyaline cartilage repair.