Background: There are numerous methods of the superior labrum anterior and posterior (SLAP) lesion repair. The purpose of this study was to investigate the superior labrum and the origin of the long head of the biceps tendon (LHB) histoanatomically in order to propose the ideal repair of the SLAP lesions.
Methods: Twenty-eight shoulders of 16 cadavers with intact LHB origin were anatomically investigated focusing on the location of the fibers of LHB origin and the supraglenoid tubercle. Among them 20 shoulders with intact superior labrum were additionally observed focusing on whether the anterior edge of LHB on the labrum (point ‘A’) was anterior to the supraglenoid tubercle. Fiber orientations of the soft tissue were also studied histologically in three glenoids.
Results: No LHB fiber was sent anterior to the anterior edge of the supraglenoid tubercle. ‘A’ was not located more posterior than the supraglenoid tubercle. Fibers of the sheet-like structure ran vertically to LHB.
Discussion: These results show that LHB fibers do not anteriorly cross over ‘A’. It is also shown that the sheet-like structure may play a role of supporting LHB and they are independent. This fact suggests that horizontal mattress suture across ‘A’ may result in non-anatomical structure, although horizontal mattress suture could make a meniscal appearance and proper motion which the normal superior labrum originally has.