@article{SchandaKeiblHeimeletal., author = {Schanda, Jakob and Keibl, Claudia and Heimel, Patrick and Monforte, Xavier and Feichtinger, Xaver and Teuschl, Andreas and Baierl, Andreas and Muschitz, Christian and Redl, Heinz and Fialka, Christian and Mittermayr, Rainer}, title = {Zoledronic Acid Substantially Improves Bone Microarchitecture and Biomechanical Properties After Rotator Cuff Repair in a Rodent Chronic Defect Model}, series = {Am J Sports Med}, volume = {2020 Jul}, journal = {Am J Sports Med}, number = {48 (9)}, pages = {2151 -- 2160}, abstract = {Background: Bone mineral density at the humeral head is reduced in patients with chronic rotator cuff tears. Bone loss in the humeral head is associated with repair failure after rotator cuff reconstruction. Bisphosphonates (eg, zoledronic acid) increase bone mineral density. Hypothesis: Zoledronic acid improves bone mineral density of the humeral head and biomechanical properties of the enthesis after reconstruction of chronic rotator cuff tears in rats. Study design: Controlled laboratory study. Methods: A total of 32 male Sprague-Dawley rats underwent unilateral (left) supraspinatus tenotomy with delayed transosseous rotator cuff reconstruction after 3 weeks. All rats were sacrificed 8 weeks after rotator cuff repair. Animals were randomly assigned to 1 of 2 groups. At 1 day after rotator cuff reconstruction, the intervention group was treated with a single subcutaneous dose of zoledronic acid at 100 µg/kg bodyweight, and the control group received 1 mL of subcutaneous saline solution. In 12 animals of each group, micro-computed tomography scans of both shoulders were performed as well as biomechanical testing of the supraspinatus enthesis of both sides. In 4 animals of each group, histological analyses were conducted. Results: In the intervention group, bone volume fraction (bone volume/total volume [BV/TV]) of the operated side was higher at the lateral humeral head (P = .005) and the medial humeral head (P = .010) compared with the control group. Trabecular number on the operated side was higher at the lateral humeral head (P = .004) and the medial humeral head (P = .001) in the intervention group. Maximum load to failure rates on the operated side were higher in the intervention group (P < .001). Cortical thickness positively correlated with higher maximum load to failure rates in the intervention group (r = 0.69; P = .026). Histological assessment revealed increased bone formation in the intervention group. Conclusion: Single-dose therapy of zoledronic acid provided an improvement of bone microarchitecture at the humeral head as well as an increase of maximum load to failure rates after transosseous reconstruction of chronic rotator cuff lesions in rats. Clinical relevance: Zoledronic acid improves bone microarchitecture as well as biomechanical properties after reconstruction of chronic rotator cuff tears in rodents. These results need to be verified in clinical investigations.}, subject = {Tissue Engineering}, language = {en} } @article{FeichtingerMonforteKeibletal., author = {Feichtinger, Xaver and Monforte, Xavier and Keibl, Claudia and Hercher, David and Schanda, Jakob and Teuschl, Andreas and Muschitz, Christian and Redl, Heinz and Fialka, Christian and Mittermayr, Rainer}, title = {Substantial Biomechanical Improvement by Extracorporeal Shockwave Therapy After Surgical Repair of Rodent Chronic Rotator Cuff Tears.}, series = {American Journal of Sports Medicine}, journal = {American Journal of Sports Medicine}, subject = {Shockwave Therapy}, language = {en} } @article{FeichtingerHeimelTangletal., author = {Feichtinger, Xaver and Heimel, Patrick and Tangl, Stefan and Keibl, Claudia and N{\"u}rnberger, Sylvia and Schanda, Jakob Emanuel and Hercher, David and Kocijan, Roland and Redl, Heinz and Grillari, Johannes and Fialka, Christian and Mittermayr, Rainer}, title = {Improved biomechanics in experimental chronic rotator cuff repair after shockwaves is not reflected by bone microarchitecture}, series = {PLoS One}, volume = {17}, journal = {PLoS One}, number = {1}, doi = {10.1371/journal.pone.0262294}, subject = {chronic rotator cuff repair}, language = {en} }