In the past decade, three distinct systems for addressing focal cartilage lesions in the knee through resurfacing have emerged, namely the Hemicap/Unicap, BioPoly and Episealer systems. These technologies provide a new approach for treating patients who might not be suitable candidates for other biological treatment options. Specifically, they target individuals considered too old to benefit from biologic repair methods, but who are also too young for a unicompartmental knee arthroplasty. The three systems have demonstrated promising clinical outcomes, with the literature showing that they can effectively relieve pain and restore knee function, with success rates comparable to other established treatments for cartilage injuries. An additional advantage of these surface replacement systems is their relatively short rehabilitation period, which allows for a quicker return to daily activities. In conclusion, they are an ideal option for ‘gap-age’ patients, representing a valuable alternative for managing knee cartilage defects in this specific patient cohort.