Augmentation in Rotator Cuff Repair – Where Are We Now?
By: Chaitu S. Malempati, M.D. and Andrew Croft, M.S.4
To this day, rotator cuff pathology remains a common problem. As our population ages, the number of patients who are affected continues to rise. Rotator cuff tendon tears affect between 30-50% of people older than 50 years of age.1-2 Despite a comprehensive understanding of rotator cuff and biomechanically advanced surgical repair techniques, there is still a subset of rotator cuff tears that go on to failure.3-4 The outcomes of rotator cuff repair depend on a multitude of factors including tear size, chronicity, patient age, muscle atrophy and patient comorbidities.5-6 The inability to obtain high healing rates and optimal outcomes has spurred the advancement of augmentation techniques, biologics and various adjuncts. However, the question remains: Where are we now with these advancements in rotator cuff repair?
Over the past 15 years, there has been a growing scientific interest in using exogenously supplied growth factors or growth factor stimulators to improve surgical outcomes.7 This approach augments the healing environment where the reconstructed rotator cuff heals. Platelet-rich plasma (PRP) involves a concentration of platelets that contain growth factors and cytokines and can be locally applied to damaged tissue to improve wound healing.8 Even though PRP use has increased, its effectiveness remains controversial. While some studies have concluded that PRP treatment (specifically leukocyte-poor PRP) is effective in healing injured or repaired tendons and ligaments quicker than without PRP treatment,9 other studies have found no significant statistical difference when comparing patients treated with PRP and those that are untreated for rotator cuff repair.10 Matrix metalloproteinase (MMP) inhibitors are the enzymes responsible for extracellular matrix (ECM) degradation. Studies have shown that MMP concentrations increase in degenerative rotator cuff tissues as well as in postsurgical rotator cuff tissue, particularly MMP-13.11 Bedi et al. concluded that modulating MMP-13 activity after rotator cuff repair may offer a novel biologic pathway to augment tendon-to-bone healing;12 however, further investigative work into MMP inhibition’s role in rotator cuff repair augmentation is needed.
The idea behind using stem cell therapy is to improve surgical rotator cuff repair’s success rate through augmenting the healing environment. Recent studies have applied mesenchymal stem cell (MSC) therapy with varying levels of success to rotator cuff repair.13 Studies have investigated MSCs derived from different tissues to varying degrees, and although they all evoke the same general effects, some lineages seem to have a superior capacity for tissue regeneration such as bone marrow-derived MSCs.14 Using MSCs for rotator cuff surgery is one of the most promising new areas of biologic augmentation; its drawbacks, however, necessitate further research and technological advancement.
In recent years, there has been significant interest in developing synthetic, biodegradable or bioinductive materials for repairing soft-to-hard tissue interfaces.15 Using dermal allografts, patches and bioinductive implants have all increasingly become popular methods for rotator cuff repair.16 The bioinductive collagen patch has shown new tendon formation on ultrasound and MRI with no complications, and also demonstrates relatively high healing rates at two-year follow-up for large and massive rotator cuff tears.17 Many are taking great interest in developing biomaterials that successfully integrate the tendon-bone interface more effectively, including scaffold mesh, nanofiber-based scaffold, gelatin hydrogel sheets and injectable hydrogel.
While this short overview does not list all the available augmentation techniques and adjuncts currently in use, it highlights the differences between treatment options and outlines the literature that’s available. Steroidal treatments, transforming growth factor (TGF)-Beta, vascular endothelial growth factor (VEGF), vascular phospholipid gels and augmented sutures are just a few of the other treatment options when performing rotator cuff repair. Biologic augmentation in rotator cuff repair is an important area of research not only because it could potentially enhance injured soft-to-hard tissue interface integration, but also because many approaches have immediate implications to improve the outcomes of rotator cuff surgeries.14 Developing a physiologically and mechanically relevant biologic augmentation platform that is effective in inducing healing and integrating the tendon-bone interface could ultimately improve patient recovery and outcomes.
- Thangarajah et al. “Augmentation of Rotator Cuff Repair With Soft Tissue Scaffolds.” Orthopaedic Journal of Sports Medicine. 2015;3:2325967115587495.
- Isaac et al. “Biologic Approaches to Enhance Rotator Cuff Healing After Injury.” Journal of Shoulder and Elbow Surgery. 2012;21:181-190.
- Bedi et al. “Massive Tears of the Rotator Cuff.” Journal of Bone and Joint Surgery – American Volume. 2010;92:1894-1908.
- Greenspan et al. “Massive Rotator Cuff Tears: Pathomechanics, Current Treatment Options and Clinical Outcomes.” Journal of Shoulder and Elbow Surgery. 2015;24:1493-1505.
- Cole et al. “Arthroscopic Rotator Cuff Repair: Prospective Functional Outcome and Repair Integrity at Minimum Two-Year Follow-Up.” Journal of Shoulder and Elbow Surgery. 2007;16:579-585.
- Galatz et al. “The Outcome and Repair Integrity of Completely Arthroscopically Repaired Large and Massive Rotator Cuff Tears.” Journal of Bone and Joint Surgery – American Volume. 2004;86:219-224.
- Molloy et al. “The Roles of Growth Factors in Tendon and Ligament Healing.” Sports Medicine. 2003;33:381-394.
- Dohan et al. “Classification of Platelet Concentrates: From Pure Platelet-Rich Plasma (P-PRP) to Leucocyte and Platelet-Rich Fibrin (L-PRF).” Trends in Biotechnology. 2009:27:158-167.
- Middleton et al. “Evaluation of the Effects of Platelet-Rich Plasma (PRP) Therapy Involved in the Healing of Sports-Related Soft Tissue Injuries.” The Iowa Orthopaedic Journal. 2012;32:150-163.
- Moraes et al. “Platelet-Rich Therapies for Musculoskeletal Soft Tissue Injuries.” The Cochrane Database of Systematic Reviews. 2019.
- Del Buono et al. “Metalloproteinases and Rotator Cuff Disease.” Journal of Shoulder and Elbow Surgery. 2012;21:200-208.
- Bedi et al. “Doxycycline-Mediated Inhibition of Matrix Metalloproteinases Improves Healing After Rotator Cuff Repair.” American Journal of Sports Medicine. 2010;38(2):308-317.
- Valencia et al. “Stem Cell Therapy in The Management of Shoulder Rotator Cuff Disorders.” Wharton’s Jelly Stem Cells. 2015;7:691-699.
- Patel et al. “Advances in Biologic Augmentation for Rotator Cuff Repair.” Annals of the New York Academy of Science. 2016;1383(1):97-114.
- O’Brien et al. “Biomaterials & Scaffolds for Tissue Engineering.” Materials Today. 2011;14:88-95.
- Place et al. “Complexity of Biomaterials for Tissue Engineering.” Nature Materials. 2009;8:457-470.
- Thon et al. “Evaluation of Healing Rates and Safety With a Bioinductive Collagen Patch for Large and Massive Rotator Cuff Tears.” American Journal of Sports Medicine. 2019;47(8):1901-1908.