Cartilage lesions are relatively common with an incidence around 60% at the time of arthroscopy, of which 5% to 10% are grade IV lesions in patients under 40 years of age. Treatment options for these lesions range from nonoperative treatments including activity modification, bracing and various injections, to operative treatments including chondroplasty or more advanced cartilage restoration techniques, such as osteochondral autograft, osteochondral allograft and autologous chondrocyte implantation (ACI). ACI has been available as a treatment option for three decades and the third-generation ACI is currently used in the United States, which is defined as matrix-induced ACI (MACI). With this treatment, patient articular cartilage is harvested during a first-stage arthroscopy and then transplanted back to the patient knee during second-stage surgery with a graft that consists of a manufactured collagen membrane with chondrocytes attached to the scaffold. Randomized trials have shown that MACI is superior to microfracture at short- and mid-term follow-up. More recently, arthroscopic MACI has become available to reduce the morbidity of the second-stage procedure. The technique is straightforward and arthroscopy-dedicated equipment is helpful in performing the procedure. Previous first- and second-generation studies have shown that arthroscopic treatment leads to easier recovery and superior patient-reported outcomes at one-year follow-up with similar outcomes at five-year follow-up. Initial series of arthroscopic third-generation MACI have been shown to lead to excellent outcomes and similarly superior short-term outcomes with fewer complications, but larger comparative studies are warranted.
List et al. (Wed,) studied this question.