The Effects of Aging, Antiinflammatory Drugs, and Ultrasound on the In Vitro Response of Tendon Tissue

Abstract

We investigated the effects of aging and various treatments on rat patellar tendon using an in vitro model. In the first part of the study, the 3H-thymidine and 3H-proline incorporation rates at 12 and 24 hours were determined in transected patellar tendon explants from young (21 days), intermediate age (8 to 10 weeks), and older (4 to 6 months) rats. In the second part, the same incorporation rates were measured in the older tendon explants in response to treatment with control medium, medium with a high and low concentration of indomethacin, and medium with a high and low concentration of dexamethasone. Finally, the effects of ultrasound treatment were measured and compared with a sham ultrasound treatment. The results indicated an age-dependent response of the tendon. The youngest specimens consistently showed the highest incorporation rates. The addition of a high concentration of dexamethasone resulted in a small negative effect on the 3H-thymidine incorporation. Ultrasound and indomethacin had no significant effects. This study indicates that aging is associated with a lower metabolic activity of tendon. In this model, currently used treatment methods failed to result in direct positive effects on tendon tissue, and a high concentration of dexamethasone appeared to have a small negative effect.

Synergistic effects of dexamethasone and quinolones on human-derived tendon cells

“…In vitro studies revealed degenerative changes, reduced synthesis of collagen type I and proteoglycans, as well as decreased cell proliferation, viability and metabolism following glucocorticoid exposure [26][27][28][29][30]. Experimental evidence on the effects of steroids in combination with quinolones is even more limited.…”

Physician Prescribing Patterns of Oral Corticosteroids for Musculoskeletal Injuries

“…16,17 The use of corticosteroids for chronic tendonitis is suspect, because this condition is degenerative rather than inflammatory. 2,18 Corticosteroids have been prescribed extensively for a multitude of conditions, and their side effects are well documented. Serious side effects are most likely with prolonged or high-dose use.…”

“…Many authors believe there is no role for the use of oral corticosteroids in sports injuries. [1][2][3][4][5] In practice, although, it seems they are used frequently.…”

Etiology of Patellar Tendinopathy in Athletes

“…3,16,31 This is thought to lead to focal degeneration and microtears in the tendon. 1,3,15,17,24,32 Many athletes are able to sustain these high forces and repetitive loads without developing patellar tendinopathy, but others develop this painful and debilitating syndrome. Some attribute the development of patellar tendinopathy to failed healing.…”