Osteochondral solutions for cartilage lesions of the knee: a narrative review.

Background and Objective: Cartilage lesions of the knee occur frequently and can cause debilitating symptoms such as pain, swelling, locking, clicking, or catching. In some lesions, both the cartilage and underlying subchondral bone are affected, which may require treatment of both the osseous and cartilaginous units. The objective of this review was to assess the available evidence of advanced treatments for osteochondral lesions in the knee. Methods: A literature search was conducted in the electronic databases of PubMed, Embase and Cochrane Library for a narrative review on studies reporting outcomes of osteochondral knee treatments. Studies were included if they reported outcomes at minimum 1-year follow-up and had minimum 5 patients, and biomechanical, translational and basic science studies were excluded. Key Content and Findings: In addition to chondroplasty and microfracture, four major advanced osteochondral restoration procedures aimed at treating injuries to the osteochondral unit were identified in the literature, which consisted of surgical internal fixation of either acute osteochondral fragments or osteochondritis dissecans (OCD) lesions, osteochondral autograft transplantation (OAT), osteochondral allograft (OCA) transplantation and biphasic scaffold implantation. Internal fixation of acute osteochondral patellofemoral fractures has been found to have superior outcomes compared to fragment removal, but does require concomitant patellar stabilization. Fixation of OCD also leads to good outcomes without superiority for fixation method. Osteochondral autograft is an excellent treatment option for smaller defects and has a high rate of return to sport. OCA outcomes are excellent with good survival rates although reoperations can frequently occur. Finally, biphasic scaffolds are relatively recent and can be used in both more acute as well as more degenerative settings and the short-term outcomes are promising. Conclusions: Osteochondral injury in the knee requires unique treatment options as both the underlying bone and cartilage need to be treated, due to their poor healing capacity and significant cause of morbidity. Several treatment options exist and the overall outcomes of these treatments are satisfactory in improving patient-reported outcomes, and most patients can return to activities.