Objectives
Despite the increased clinical application of biologic therapies, there is a paucity of literature regarding the efficacy of intra-articular bone marrow aspirate concentrate (BMAC) injections at the time of meniscectomy for degenerative meniscus tears. Therefore, we aimed to assess the objective, subjective, and functional outcomes as well as complication rates in patients diagnosed with degenerative meniscal tears and adjacent chondral lesions. Specially, we compared outcomes between patients treated with arthroscopic partial meniscectomy (PM) and intra-articular BMAC injection to patients treated with arthroscopic PM alone.

Methods

A retrospective chart review was performed for patients diagnosed with degenerative meniscal tears of the knee. Patients were included if they were arthroscopically treated with PM and BMAC or PM alone between October 2016 and January 2019 and had more than 1-year follow-up (n=31; mean age 53 years (range, 17-65 years), 52% female; mean follow-up 30 months (range, 12-42 months). Postoperative outcomes included hamstring and quadriceps strength, range of motion, visual analog scores (VAS), University of California, Los Angeles (UCLA) activity score, Knee Outcome Score (KOS) activity of daily living (ADL) and KOS Sports scores. The average body mass index for patients in the PM/BMAC group was similar to that of the PM group (30 ± 6 vs 30 kg/m2 ± 5 kg/m2; p=0.779) (Table 1). However, the mean Outerbridge classifications of the adjacent chondral lesions were higher among the PM/BMAC group (2 ± 0.7 vs 0.9 ± 0.9 femur; p=0.005, 2.3 ± 1.1 vs 1.3 ± 0.7 tibia; p=0.022).

Results

Postoperatively, mean hamstring and quadriceps strengths were similar between the PM/BMAC and PM groups (4.7 ± 0.5 vs 4.3 ± 1.6; p=0.512, 4.6 ± 0.5 vs 4.5 ± 0.5; p=0.056, respectively). Mean postoperative knee flexion was also similar between the PM/BMAC and PM groups (131 ± 5 vs 130° ± 5°; p=0.490). All patients regained full extension in both groups. Mean postoperative VAS scores were lower among the PM/BMAC group (1.9 ± 2.2 vs 3.1 ± 2.8; p=0.200). Mean UCLA scores were similar between the groups (6.7 ± 3.1 PM/BMAC vs 6.6 ± 2.5 PM; p=0.947). Mean KOS ADL and KOS Sport scores were higher among patients treated with PM/BMAC (84 ± 21 vs 80 ± 18; p= 0.562, 80 ± 24 vs 70 ± 29; p=0.328, respectively). There were greater mean differences in VAS and UCLA scores for the PM/BMAC group (-3.7 ± 2.7 vs -1.7 ± 3.4; p=0.123, 0.8 ± 3.0 vs -0.1 ± 2.5; p=0.422, respectively). Two patients in the PM/BMAC group and one PM patient underwent a series of hyaluronic acid injections due to persistent pain. No subsequent surgeries were noted among the groups.

Conclusion

Patients treated for degenerative meniscal tears with adjacent chondral lesions had improved postoperative outcomes when treated with both arthroscopic PM and BMAC and PM alone. However, despite the more advanced adjacent cartilage damage, PM and BMAC patients had superior postoperative outcomes as evidenced by VAS, KOS ADL, and KOS Sport scores. Prospective and longer-term studies are necessary to further elucidate how these interventions compare.