Anatomical and histologicalstudy of the tendo achilles

ABSTRACT

Tendo Achilles is the common tendon of soleus and gastrocnemius muscles. Achilles tendon disorders and abnormalities are commonly seen by sports medicine physicians. Posterior heel pain is multifactorial and may be due to changes of the tendo Achilles near its insertion. Moreover, anatomic and operative textbooks did not clearly describe the Achilles tendon attachment to the calcaneus. Was to study the length, width and mode of insertion of the tendo Achilles and its relation to the sural nerve. The study was carried out on 25 dissected lower limbs of adult human cadavers. Three tendons were prepared for histological study under light microscope. The study revealed that in 72% of cases, the tendon was inserted into the back of calcaneus with a crescentic opposing surface to the calcaneus, in 12% of cases, there was an extension of the tendon to the plantar aponeurosis but in 8% of cases, the insertion continued to the plantar aponeurosis giving origin to the abductor hallucis muscle. The remaining 8% of cases showed a prolongation of tendo Achilles joining another prolongation from the plantar aponeurosis extending to the tuberosity of navicular bone. In all cases, there was an intervening bursa between the tendon and the back of calcaneus. The mean length of the tendon from the musculo-tendinous junction of gastrocnemius and soleus muscles till the calcaneus was 22.18 +/- 3.12 cm and 7.62 +/- 1.71 cm respectively. The mean width of the tendon was 6.62 +/- 0.52 cm at its junction with the gastrocnemius, 2.88 +/- 0.32 cm at its junction with the soleus and 2.55 +/- 0.34 cm at its attachment to the calcaneus. The sural nerve was found 1.48 +/- 0.41 cm on the lateral aspect of tendo Achilles at its insertion. The histological study of the tendon revealed that it was formed of parallel collagen fibers with a fibrocartilage at the insertion site. The insertional region of the tendon is said to have stress concentration. Hence, the presence of fibrocartilages for protection of the tendon. Extensions of the insertion of the tendo Achilles has a role in the biomechanics and movements of the ankle and subtalar joints. The relation of the sural nerve to tendo Achilles should be concerned when suturing a ruptured tendon or any surgical interference