The influence of cell and platelet number on clinical outcomes provided by a one-step scaffold transplantation with bone marrow concentrate for the treatment of osteochondral lesions of the talus.

Purpose: The aim of this study was to investigate if the numbers of cells and platelets in the bone marrow aspirate concentrate (BMAC) added to a hyaluronic acid membrane influence the clinical outcome up to long-term follow-up in the treatment of osteochondral lesions of the talus (OLTs).

Methods: A total of 102 patients with symptomatic OLTs underwent this one-step treatment. Eighty-five patients (53 men, 32 women, age 32.3 ± 10.6 years, lesion size 2.7 ± 1.6 cm) were prospectively evaluated at baseline and at 2-5-10 years using the AOFAS ankle-hindfoot score, the NRS for pain, and the Tegner score. Satisfaction and failures were documented as well. Laboratory analysis of BMAC was performed for the count of mononucleated cells (MNCs) and platelets.

Results: The AOFAS improved from baseline (59.1 ± 13.7) to the final follow-up (82.3 ± 14.9, p < 0.0005). NRS improved from 7.1 ± 1.1 at baseline to 3.9 ± 2.8 at the final follow-up (p < 0.0005). Tegner improved from a pre-op 2.0 median to 3.0 at the final follow-up (p < 0.0005), not reaching the pre-injury level. MNCs and platelets in BMAC were 148.2 ± 54.2 × 10/L and 454.3 ± 277.5 × 10/L, respectively. MNCs correlated with NRS at 2 years (p = 0.018; rho=-0.260). However, MNCs number, as well as platelet number, did not influence the improvement from baseline of the clinical scores at all follow-up evaluations.

Conclusion: This study demonstrated, in a large series of patients evaluated up to a long-term follow-up, that the number of MNCs and platelets present in BMAC does not influence the overall clinical outcomes in patients affected by OLTs treated with a one-step hyaluronic acid scaffold implantation augmented with BMAC.

Level Of Evidence: IV.