Effects of corticosteroids and hyaluronic acid on torn rotator cuff tendons in vitro and in rats

Abstract

Corticosteroids (CS) or hyaluronic acid (HA) is used in subacromial injection for the conservative treatment of rotator cuff tears (RCT); this study addresses the question of how CS and HA affect the tendon tissue and fibroblasts in vitro and in rats. Cell proliferation assays were performed in human tendon fibroblasts from RCT. Rats underwent surgery to create RCT, and the surgical sites were injected with CS or HA. The rotator cuff tendons were subjected to biomechanical testing, microscopic and immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), and ultrastructural analysis. Cell proliferation was significantly decreased with CS in vitro (p < 0.05). Maximal load of CS-treated tendons was significantly decreased compared with that of HAtreated tendons (p < 0.05), as well as PCNA þ cells at 2 weeks (p < 0.05). Ultrastructural observations of the CS-treated rats detected apoptosis of tendon fibroblasts 24 h after surgery. Histological and biomechanical data 4 weeks after surgery were not significant among the three groups. Unlike HA, CS caused cell death, and inhibition of the proliferation of tendon fibroblasts, leading to a delay of tendon healing involved and a subsequent decrease of biomechanical strength at the surgical site. Keywords: tendon; corticosteroids; hyaluronic acids; totator cuff tears; tendon fibroblast Rotator cuff tears (RCT) occur in the middle-aged and elderly people and cause severe shoulder pain. The prevalence of RCT ranges from 5% to 40% in the general population, 1 increasing linearly with age from the third decade. [2][3][4] In clinical settings, initial treatment of RCT to alleviate shoulder pain and restore shoulder function employs subacromial injection of corticosteroids (CS), administration of nonsteroid antiinflammatory drugs, and physical therapy.

Pre-operative corticosteroid injections improve functional outcomes in patients undergoing arthroscopic repair of high-grade partial-thickness rotator cuff tears

“…The results of several systematic reviews and meta-analyses over decades suggest there may be short-term symptomatic relief after CSI, but these results are often difficult to reproduce [4][5][6][7][8] . In addition, case reports from the past have suggested a correlation of CSI and tendon rupture [19][20][21] , which has been confirmed in multiple animal models 6,9,10,22 . Previous studies have also shown an increase in post-operative infection rates in patients who received pre-or peri-operative CSI's [23][24][25] , but recent systematic reviews and meta-analyses have challenged these claims 11,13,26,28 .…”

Complete Rotator Cuff Tear: An Evidence-Based Conservative Management Approach

“…The same study also conducted an experiment on the effects of CS and HA injections in rats. Like the in vitro study, the animal study found apoptosis in rotator cuff tendons, inhibition of cell proliferation, a delay in tendon healing, and decreased biomechanical strength in CS subjects [59].…”

“…A 2015 in vitro study found that CS injections decreased cell proliferation in rotator cuff tendons, and the resulting strength of these tendons decreased as compared to the strength after HA injections [59]. The same study also conducted an experiment on the effects of CS and HA injections in rats.…”

The Effect of Sodium Hyaluronate on Ligamentation and Biomechanical Property of Tendon in Repair of Achilles Tendon Defect with Polyethylene Terephthalate Artificial Ligament: A Rabbit Tendon Repair Model

“…In a previous study, Li et al found out that polyethylene terephthalate (PET) artificial ligament grafts coated with sodium hyaluronate can enhance cell adhesion, facilitated cell growth, and suppressed the expression of inflammation-related genes relative to a pure PET graft for ACL reconstruction [21]. Another study done by Nakamura et al demonstrated that HA possesses anti-inflammatory and antiadhesive activities in tendon and synovial fibroblasts derived from RCT [22]. In addition, Salamanna et al find out that, after repeated peripatellar injections of HA to rats, a significantly higher proliferation rate and viability, along with increased synthesis of C-terminal-propeptide of type I collagen, fibronectin, aggrecan, tenascin-c, and matrix-metalloproteinase-3 show respect to control group [23].…”