Patellar tendon morphology in volleyball athletes with and without patellar tendinopathy.
Kulig K, Chang TJ, Hannanvash N, Reischl SF, Song P, and Bashord GR. Scand J Med Sci Sports. 2012: 1-8.
Patellar tendinopathy is common in athletics, especially among volleyball players. The condition occurs due to degeneration and/or inflammation secondary to physical activity. Additionally, clinical imaging struggles to distinguish between inflammatory and degenerative conditions further complicating diagnosis and thus, management. Therefore, Kulig and colleagues sought to perform a detailed analysis of patellar tendon collagen bundle organization in elite male volleyball athletes. The authors recruited 94 male participants (10 controls and 84 NCAA Division I or Olympic volleyball players) over 6 feet tall. The 84 volleyball players were divided into those with anterior knee pain near the patellar tendon (symptomatic, 44 players) and those without (asymptomatic, 40 players). All participants completed a VISA-P questionnaire (lower VISA-P score indicated more pain and restrictions). Furthermore, the researchers collected anthropometric data (body mass, height, etc.) and conducted personal interviews. Lastly, the researchers performed B-mode ultrasound imaging to assess the collagen organization and thickness of the patellar tendons. While B-mode ultrasound cannot specifically identify inflammation, the researchers considered inflammation to be the cause of the tendinopathy if the athlete was symptomatic, yet did not demonstrate collagen disorganization, thus ruling out degenerative changes to the tendon. Overall, patellar tendons of asymptomatic athletes, and athletes with tendinopathy, demonstrated greater proximal tendon thicknesses compared to control participants; however VISA-P scores were significantly lower in symptomatic athletes than asymptomatic athletes. Symptomatic athletes also had greater collagen bundle disorganization (degeneration) compared to both control participants and asymptomatic volleyball players.
The presence of collagen bundle disorganization and lower VISA-P scores suggests that symptoms of tendinopathy are associated with tendon degeneration rather than inflammatory responses, although all athletes displayed morphological changes to the tendon compared to control participants. While interesting one should be cautious not to generalize these findings to the general population. The current study observed only elite male volleyball players. These athletes may be unique because of their high volume of training, which may explain why athletes had thicker tendons than control participants. In order to increase generalizability, future research should compare various levels of competition (recreational, high school) and sports to healthy controls. Further, it would be interesting to follow athletes over time to determine when and how certain aspects of training begin to induce healthy adaptation (thickness) and degenerative changes. Eventually, this data conceivably could optimize training regiments for volleyball athletes so as to prevent tendinopathy from occurring. In the meantime, given this information, clinicians should be aware that volleyball athletes (as well as possibly other athletes) who present with recurrent patellar tendon pain may be experiencing tendonosis rather than tendonitis and could respond to a change in treatment approach. Tell us what you think. Have you seen athletes which, given this information may be experiencing patellar tendonosis rather than tendonitis? Further, do you see this evidence changing how you treat tendinopathies which may be degenerative changes more so than inflammatory change?
Written by: Kyle Harris
Reviewed by: Laura McDonald
Related Posts:Kulig K, Landel R, Chang YJ, Hannanvash N, Reischl SF, Song P, & Bashford GR (2012). Patellar tendon morphology in volleyball athletes with and without patellar tendinopathy. Scandinavian Journal of Medicine & Science in Sports PMID: 23253169