PMID- 32543880 OWN - NLM STAT- MEDLINE DCOM- 20201112 LR - 20201112 IS - 1552-3365 (Electronic) IS - 0363-5465 (Linking) VI - 48 IP - 9 DP - 2020 Jul TI - Zoledronic Acid Substantially Improves Bone Microarchitecture and Biomechanical Properties After Rotator Cuff Repair in a Rodent Chronic Defect Model. PG - 2151-2160 LID - 10.1177/0363546520926471 [doi] AB - 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 microg/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. FAU - Schanda, Jakob E AU - Schanda JE AD - AUVA Trauma Center Vienna-Meidling, Department for Trauma Surgery, Vienna, Austria. AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. FAU - Keibl, Claudia AU - Keibl C AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. FAU - Heimel, Patrick AU - Heimel P AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. AD - Medical University of Vienna, Department of Oral Surgery, Karl Donath Laboratory for Hard Tissue and Biomaterial Research, Vienna, Austria. FAU - Monforte, Xavier AU - Monforte X AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. AD - University of Applied Sciences Technikum Wien, Department of Life Science Engineering, Vienna, Austria. FAU - Tangl, Stefan AU - Tangl S AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. AD - Medical University of Vienna, Department of Oral Surgery, Karl Donath Laboratory for Hard Tissue and Biomaterial Research, Vienna, Austria. FAU - Feichtinger, Xaver AU - Feichtinger X AD - AUVA Trauma Center Vienna-Meidling, Department for Trauma Surgery, Vienna, Austria. AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. FAU - Teuschl, Andreas H AU - Teuschl AH AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. AD - University of Applied Sciences Technikum Wien, Department of Life Science Engineering, Vienna, Austria. FAU - Baierl, Andreas AU - Baierl A AD - University of Vienna, Department of Statistics and Operations Research, Vienna, Austria. FAU - Muschitz, Christian AU - Muschitz C AD - St Vincent Hospital Vienna, II. Medical Department, Metabolic Bone Disease Unit, Vienna, Austria. FAU - Redl, Heinz AU - Redl H AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. FAU - Fialka, Christian AU - Fialka C AD - AUVA Trauma Center Vienna-Meidling, Department for Trauma Surgery, Vienna, Austria. AD - Sigmund Freud University, Medical Faculty, Center for the Musculoskeletal System, Vienna, Austria. FAU - Mittermayr, Rainer AU - Mittermayr R AD - AUVA Trauma Center Vienna-Meidling, Department for Trauma Surgery, Vienna, Austria. AD - Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria. AD - Austrian Cluster for Tissue Regeneration, Vienna, Austria. LA - eng PT - Journal Article DEP - 20200616 PL - United States TA - Am J Sports Med JT - The American journal of sports medicine JID - 7609541 RN - 6XC1PAD3KF (Zoledronic Acid) SB - IM MH - Animals MH - Biomechanical Phenomena MH - *Bone Density MH - Male MH - Random Allocation MH - Rats MH - Rats, Sprague-Dawley MH - *Rotator Cuff/surgery MH - *Rotator Cuff Injuries/surgery MH - Wound Healing MH - X-Ray Microtomography MH - Zoledronic Acid/*therapeutic use OTO - NOTNLM OT - biomechanical analysis OT - bone microarchitecture OT - chronic rotator cuff tears OT - histological analysis OT - micro-computed tomography OT - zoledronic acid EDAT- 2020/06/17 06:00 MHDA- 2020/11/13 06:00 CRDT- 2020/06/17 06:00 PHST- 2020/06/17 06:00 [pubmed] PHST- 2020/11/13 06:00 [medline] PHST- 2020/06/17 06:00 [entrez] AID - 10.1177/0363546520926471 [doi] PST - ppublish SO - Am J Sports Med. 2020 Jul;48(9):2151-2160. doi: 10.1177/0363546520926471. Epub 2020 Jun 16.