Abstract
Aim: We hypothesize that anabolic steroid administration enhances matrix remodelling and improves the biomechanical properties of bio-artificially engineered human supraspinatus tendons (BATs).
Method: BATs were treated either with nandrolone decanoate (NLS group, n=18), stretching (LNS group, n=18), or both (LS group, n=18). A control group received no treatment (NLNS group, n=18). BATs’ contractility was assessed by daily scanning and two dimensional analysis. Cytoskeletal organization was evaluated microscopically with DAPI and rhodamine phalloidin staining. Matrix metalloproteinase-3 (MMP-3) levels – an indicator of matrix remodelling – were discerned by ELISA assay, and biomechanical properties by load-to-failure testing.
Results: The LS group showed greatest contractility and the best-organized actin cytoskeleton when compared to the other groups. On the second and third day of treatment, MMP-3 levels in the LS group were significantly greater than those of NLNS group and greater than NLS and LNS groups. The biomechanical properties (load to failure, ultimate stress, ultimate strain, elastic modulus, and energy to failure) in the LS group were significantly improved when compared to NLNS and NLS (p< .05) groups and 26–48% greater than those in LNS group.
Conclusions: Nandrolone decanoate and load act synergistically to increase matrix remodelling and biomechanical properties of bioengineered human supraspinatus tendons. Carefully prescribed and monitored, anabolic steroids may have an important adjunct role in postoperative healing and rehabilitation of repaired rotator cuff tendons. More research is necessary to fully evaluate the safety and efficacy of anabolic steroids in this application.
The abstracts were prepared by Eleni Koutsoukou. Correspondence should be addressed to him at the Hellenic Association of Orthopaedic Surgery and Traumatology (HAOST), 20, A. Fleming str, 15123 Marousi, Athens, Greece.
