抄録
Arthroscopic rotator cuff repair has become increasingly popular. There have been several procedure related studies using human cadaveric shoulders. In some studies, animal shoulders have been used as the consistency of their tissue. To our knowledge, there has been only one biomechanical study using porcine shoulders. However the properties of the tendon were not examined in the study. The objective of this study was to know the biomechanical properties of the porcine infraspinatus tendon.
5 fresh frozen porcine shoulders (6 months old) were dissected, while the infraspinatus tendons were left intact. The thickness of the infraspinatus tendons and the size of the footprints were measured. To evaluate the biomechanical property, tensile testing was performed using a material testing machine AUTOGRAPH AG-ITM. The specimens were loaded to failure at the rate of 1mm/s. The structural properties of linear stiffness, yield load, and ultimate load were calculated using software TRAPEZIUMTM. The geometric properties were as follows: the mean thickness of the infraspinatus tendon, 5.9±1.6mm; the mean size of the footprint, 25.9±4.5mm in the anterior-posterior direction, 13.8±1.7mm in the medial-lateral direction. The biomechanical properties of the infraspinatus tendon were as follows: yield load, 643.1±200. 6N; ultimate load, 868.7±190. 1N; linear stiffness, 136.0±44.6N/mm. According to previous cadaveric studies using human shoulders, the thickness of the supraspinatus tendon was 5.8mm, the footprint was 16.3mm to 25mm in anterior-posterior direction and 12.3mm to 12.7mm in medial-lateral. The ultimate load of supraspinatus tendon ranged from 652N (average age, 64 years old) to 1007N (average age, 55 years old). The geometric and biomechanical properties of the porcine infraspinatus were similar to those of the human supraspinatus tendon. Therefore, the porcine infraspinatus tendon can be used for the biomechanical testing to evaluate the rotator cuff repair techniques.
