There was a thread we ran quite a ways back (Nov '05 I think) where the question was asked about the relationship between AAS and tendon rupture. I thought I'd repost my thoughts on that if anyone might be interested:
Most of what we know, at least histologically, about the effects of steroids on tendon structure comes from studies of corticosteroids which are commonly injected to alleviate the pain and inflammation from acute tendinitis. This is a common, and very effective, treatment but has a known complication rate of tendon rupture after injection. This complication has also been corroborated with oral corticosteroid use.
As such, researchers have spent considerable time investigating this relationship at the cellular level. At the tendon level, glucocorticoids suppress human tenocyte cellular activity, reduce tenocyte viability, and reduce collagen production, leading to altered tendon structure and predisposition to injury (Wong et al Clin Orthop Rel Res 2004; Wong et al J Bone and Joint Surg 2003).
There has been no effort spent on closely examining this effect in the case of anabolic steroids, likely because of the obvious illicit nature of their use and the fact that not many doctors actually give a sh*t about us (myself withstanding
). However, case examples of tendon rupture have been described among anabolic steroid users with increasing frequency. At the surface level, one could surmise that these individuals rupture their tendons simply due to the fact that they are engaged in high demand activities. I know of one report where ruptured tendons from two anabolic steroid users were examined, with two non-steroid users as controls. Gross microscopic examination revealed no obvious difference in the collagen fibril ultrastructure among the four individuals, leading the authors to conclude that use of steroids did not induce tendinous changes that lead to rupture (Evans et al Injury 1998).
However, one thing that does seem to distinguish tendon rupture in anabolic steroid users from non-users and from those after local and systemic glucocorticoid administration is the predilection for BILATERAL, SPONTANEOUS rupture of tendons. This event is unusual, and is not typically described in weightlifters who do not use anabolics. Also, the events do not always seem to occur during weightlifting activity. There may of course be a bias towards reporting these cases in steroid users, though, because they are "sexier" topics and often make it past journal reviewers.
That being said, overall I think the medical literature does support the concept. As well, most of us probably know someone at the gym who this has happened to, and most likely it was one of the big AAS boyz...
Of course, there is also the possibility that while on AAS, the user simply achieves a strength in the muscle that far exceeds the strength of his tendons and rupture occurs purely from that heightened load. More likely, I would suggest a concept of "the perfect storm," i.e. greatly increased load + tenocyte dysfunction = tendon rupture.
