Unicompartmental osteoarthritis: an integrated biomechanical and biological approach as alternative to metal resurfacing.

PURPOSE: Although traditionally not indicated for the treatment of osteoarthritis (OA), regenerative procedures are becoming a focus of increased interest due to their potential to provide pain relief and alter the progression of degenerative diseases. The purpose of this study was to assess whether a combined biomechanical and biological approach could offer good results in unicompartmental OA, thus delaying the need for unicompartmental arthroplasty in patients too young or refusing metal resurfacing. METHODS: Forty-three patients (mean age = 40.1 ± 11 years, 33 men and 10 women, mean BMI = 25 ± 3) affected by unicompartmental OA (Kellegren-Lawrence score = 3) in stable joints were enrolled and treated consecutively. Fifteen patients were treated with osteotomy and osteochondral biomimetic scaffold implant (3 of them also with meniscal substitution), 11 with osteotomy and meniscal scaffold implant, 9 with osteotomy and meniscal allograft implant, and 8 with both cartilage and meniscal reconstruction, depending on the specific joint compartment main requirements. Clinical evaluation was performed at 3-year (2-4) median follow-up using the following scoring systems: IKDC subjective and objective, VAS for pain, and Tegner scores. Failures, adverse events, and complications were also reported. RESULTS: The IKDC subjective score improved from 47.3 to 79.6 at the final evaluation (p < 0.0005), VAS improved from 6.1 to 2.3 (p < 0.0005), and also sport activity level evaluated with the Tegner score showed a significant improvement, from 2 (1-5) to 4 (3-10; p < 0.0005), even if without achieving the pre-injury level (6, p = 0.001). A further subanalysis confirmed the positive outcome obtained in all the treatment subgroups and showed a higher clinical improvement in patients under the age of 40 years (IKDC subjective 84.4 ± 13.2 vs 76.5 ± 17.3; p = 0.03). CONCLUSION: This integrated biological and biomechanical approach produced a marked improvement at short-medium follow-up in patients affected by unicompartmental OA. Even though a good outcome was achieved at all ages, patients under the age of 40 years presented a greater clinical and subjective improvement. Longer follow-up studies are needed to show results over time and confirm this approach as an effective alternative to unicompartmental implants.