Hyaluronic scaffold transplantation with bone marrow concentrate for the treatment of osteochondral lesions of the talus: durable results up to a minimum of 10 years

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 cm2) 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 × 109/L and 454.3 ± 277.5 × 109/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.

Regeneration of Osteochondral Lesion of the Talus with Retrograde Drilling Technique: An In Vitro Pilot Study

Background: Retrograde Drilling (RD) is a surgical technique employed for osteochondral lesions of the talus (OCLTs) to reach the subchondral bone lesion from behind, thus preserving cartilage integrity. The aim of the present pilot study was to set up an in vitro model of OCLTs to evaluate the regenerative potential of biological approaches that could be associated with the RD technique. Methods: For this purpose, an OCLT was created in human osteochondral specimens, to try to mimic the RD technique, and to compare the regenerative potential of two biological treatments. For this purpose, three groups of treatments were performed in vitro: (1) no treatment (empty defect); (2) autologous bone graft (ABG); (3) hyaluronic membrane enriched with autologous bone marrow cells. Tissue viability; production of Collagen I and II, Vascular Endothelial Growth Factor, and Aggrecan; and histological and microCT evaluations were performed after 30 days of culture in normal culture conditions. Results: It was observed that Group 3 showed the highest viability, and Group 2 showed the highest protein production. From a histological and microtomographic point of view, it was possible to appreciate the structure of the morcellized bone with which the defect of Group 2 was filled, while it was not yet possible to observe the deposition of mineralized tissue in Group 3. Conclusions: To conclude, this pilot study shows the feasibility of an alternative in vitro model to evaluate and compare the regenerative potential of two biological scaffolds, trying to mimic the RD technique as much as possible. The tissues remained vital for up to 4 weeks and both ABG and hyaluronic acid-based scaffolds stimulated the release of proteins linked to regenerative processes in comparison to the empty defect group.