Vascular density of the posterior tibial tendon: a cadaver study.

BACKGROUND: Degenerative pathology of the posterior tibial tendon, a common cause of foot and ankle dysfunction, frequently affects women over 40 years of age. Its etiology is still controversial. The literature reports decreased vascularization coinciding with the most common site of the lesion, near the medial malleolus. METHODS: Forty pairs of PTT obtained from human cadavers were transversally cut into six levels, from the musculotendon transition to its insertion point. In each segment, a histologic cut was made and stained with Masson's trichrome allowing viewing of the vascular structure of the tendon under a light microscope. By using an integrating eyepiece on the microscope, vascular density was calculated. This verified any variation of the vascular concentration in the normal tendon, a possible cause of its degeneration. RESULTS: When the results were compared by side, sex, and age, no statistically significant difference was observed. When the levels were compared, no area of decreased vascularization was seen in the midportion of the tendons, the most common site of degeneration of the posterior tibial tendon. CONCLUSION: These results indicate that an area of decreased vascularity is not a factor in degeneration of the posterior tibial tendon at the medial malleolus.