%0 Journal Article
%T Effect of prostaglandin E2 injection on the structural properties of the rat patellar tendon
%A Scott T Ferry
%A Hessam M Afshari
%A Justin A Lee
%A Laurence E Dahners
%A Paul S Weinhold
%J Sports Medicine, Arthroscopy, Rehabilitation, Therapy & Technology
%D 2012
%I BioMed Central
%R 10.1186/1758-2555-4-2
%X Forty rats were divided equally into four groups. Three groups were followed for 4 weeks with the following peritendinous injection procedures: No injection (control), 4 weekly injections of saline (saline), 4 weekly injections of 800 ng PGE2 (PGE2-4 wks). The fourth group received 4 weekly injections of 800 ng PGE2 initially and was followed for a total of 8 weeks. All animals were injected bilaterally. The main outcome measurements included: the structural and material properties of the patellar tendon under tensile loading to failure, tendon collagen content, and weekly animal activity scores.The ultimate load of PGE2-4 wks tendons at 4 weeks was significantly greater than control or saline group tendons. The stiffness and elastic modulus of the PGE2 injected tendons at 8 weeks was significantly greater than the control or saline tendons. No differences in animal activity, collagen content, or mean fibril diameter were observed between groups.Four weekly peritendinous injections of PGE2 to the rat patellar tendon were not found to be an effective model of clinical tendinopathy. In contrast, improved structural and material properties of the patellar tendon were found after PGE2 injection. While PGE2 has been thought to have a contributory role in the development of tendinopathy and anti-inflammatory medications remain a common treatment, our results suggest a positive role of PGE2 in tendon remodeling in some circumstances.Tendinopathy is a frequent source of pain and disability seen in clinical practice. Common sites of tendinopathy include the rotator cuff, the common extensor origin at the elbow, the patellar tendon, and the Achilles tendon. Histologically, tendinopathy is characterized by degeneration and disorganization of collagen fibrils, increased mucoid ground substance, and the notable absence of inflammatory cells [1]. In the clinical setting, tendinopathy ranges from activity related pain to frank rupture. The pathophysiology behind development of thi
%U http://www.smarttjournal.com/content/4/1/2