A study by Kim and Kim [6], “Outcomes of footprint medialization and bone marrow stimulation in chronic retracted rotator cuff tears,” retrospectively reviewed 87 patients with chronic retracted rotator cuff tears who underwent arthroscopic rotator cuff repair with incomplete footprint coverage. The patients were divided into group 1 (54 patients who underwent footprint medialization and bone marrow stimulation) and group 2 (33 patients who underwent conventional repair). Medialization and bone marrow stimulation were performed if the tendon did not cover a footprint of >1 cm². The clinical outcomes and radiologic findings of both groups were followed for at least 2 years after the procedures. Group 1 demonstrated better outcomes for all measures at the final follow-up than group 2. Active range of motion improved significantly in both groups, with no significant postoperative differences. At 2 years after surgery, group 1 had a significantly lower retear rate (14.8%) than group 2 (36.4%) (P=0.020). In this study, the group that underwent footprint medialization and bone marrow stimulation for chronic retracted rotator cuff tears, in which complete footprint coverage was not possible, exhibited a lower retear rate and better clinical outcomes than the group that underwent conventional incomplete repair, with a minimum follow-up period of 2 years.

Although bone marrow stimulation in rotator cuff repair facilitates tendon healing using mesenchymal stromal cells and various growth factors and cytokines contained in the bone marrow of the humeral head, several studies reported no significant differences in clinical outcomes compared with conventional repair [3,7,8]. Although medialization of the supraspinatus footprint can enable bone-tendon attachment in patients in whom reattachment to the original site is not feasible because of chronic degenerative rotator cuff tears, several studies reported no significant differences in clinical results compared with non-medialized cases [9,10]. However, several studies have reported a lower retear rate in the bone marrow stimulation or medialization group compared with the conventional repair group [2,3,11].

I agree with the concept that footprint medialization combined with bone marrow stimulation can lead to a synergistic effect on tendon healing. However, because there was the potential for selection bias in this retrospective study, a randomized controlled trial is necessary for further validation. Moreover, when comparing clinical outcomes, the amount of increase in each parameter should be compared between groups.