Morphology and morphometry of the semitendinosus distal tendon in adults and foetuses

Background: The distal tendon of the semitendinosus is often used as a graft in orthopedic reconstructive surgery. Knowledge of the exact morphology of this tendon, and also the ability to predict its morphometric data are certainly helpful when planning the procedure of surgery. Comparison of the semitendinosus distal tendon anatomy in adults and foetuses may be scientifically relevant. There are no scientific reports on this tendon anatomy in foetuses. Materials and methods: Seventy semitendinosus muscles from cadavers were obtained using standard dissection techniques (50 muscles were obtained from adults and 20 from foetuses). Moreover, ultrasound examinations of 20 muscles were performed in living individuals. Results: Two main parts of the distal tendon were distinguished — the external part not covered with muscle fibres and the internal part, which is partially or entirely hidden within the muscle belly (venter). The average length of the distal tendon was 32.34 cm, while the average lengths of the external and internal parts were 9.65 cm and 12.59 cm, respectively. The external part was solid and cylindrical. The internal part was flat and rolled like a trough, thus making the tendon a poor transplant material. Similarly, the distal tendon in foetuses consisted of two parts, including the external and internal part. Conclusions: The proportions between the lengths of different muscle parts were very similar in adults and foetuses

Anatomy and morphometry of the distal gracilis muscle tendon in adults and foetuses

Ten human gracilis muscles obtained from adults and ten gracilis muscles collected from human foetuses between the 15th and 21st week of gestation were examined. The results of this preparatory study show that the gracilis muscle in adults is narrow and long — 482 mm on average. The distal tendon of gracilis muscle is long, 294 mm on average. It can be divided into two sections — external part, outside the muscle belly, and internal, intramuscular, part. The latter one is partially covered by muscle fibres and some of it is completely hidden inside the muscle belly, which is on average 76 mm long. Presence of an intramuscular part of the distal tendon was also demonstrated in the foetal material. Moreover, very strong correlations between particular muscle lengths were noted in foetuses. (Folia Morphol 2018; 77, 1: 138–143)