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Background: Both simple and mattress repair techniques have been utilized with success for type II superior labral anterior-posterior (SLAP) lesions; however, direct anatomic and biomechanical comparisons of these techniques have yet to be clearly demonstrated.

Hypothesis: For type II SLAP lesions, the mattress suture repair technique will result in greater labral height and better position on the glenoid face and exhibit stronger biomechanical characteristics, when cyclically loaded and loaded to failure through the biceps, compared with the simple suture repair technique.

Study Design: Controlled laboratory study.

Methods: Six matched pairs of cadaveric shoulders were dissected, and a clock face was created on the glenoid from 9 o’clock (posterior) to 3 o’clock (anterior). For the intact specimen, labral height and labral distance from the glenoid edge were measured using a MicroScribe. A SLAP lesion was then created from 10 o’clock to 2 o’clock. Lesions were repaired with two 3.0-mm BioSuture-Tak anchors placed at 11 o’clock and 1 o’clock. For each pair, a mattress repair was used for one shoulder, and a simple repair was used for the contralateral shoulder. After repair, labral height and labral distance from the glenoid edge were again measured. The specimens were then cyclically loaded and loaded to failure through the biceps using an Instron machine. A paired t test was used for statistical analysis.

Results: After mattress repair, a significant increase in labral height occurred compared with intact from 2.5 ± 0.3 mm to 4.3 ± 0.3 mm at 11 o’clock (P = .013), 2.7 ± 0.5 mm to 4.2 ± 0.7 mm at 12:30 o’clock (P = .007), 3.1 ± 0.5 mm to 4.2 ± 0.7 mm at 1 o’clock (P = .006), and 2.8 ± 0.7 mm to 3.7 ± 0.8 mm at 1:30 o’clock (P = .037). There was no significant difference in labral height between the intact condition and after simple repair at any clock face position. Labral height was significantly increased in the mattress repairs compared with simple repairs at 11 o’clock (mean difference, 2.0 mm; P = .008) and 12:30 o’clock (mean difference, 1.3 mm; P = .044). Labral distance from the glenoid edge was not significantly different between techniques. No difference was observed between the mattress and simple repair techniques for all biomechanical parameters, except the simple technique had a higher load and energy absorbed at 2-mm displacement.

Conclusion: The mattress technique created a greater labral height while maintaining similar biomechanical characteristics compared with the simple repair, with the exception of load and energy absorbed at 2-mm displacement, which was increased for the simple technique.

Clinical Relevance: Mattress repair for type II SLAP lesions creates a higher labral bumper compared with simple repairs, while both techniques resulted in similar biomechanical characteristics.

Background: Clinical testing for the integrity of the subscapularis muscle includes the belly-press, lift-off, and bear-hug examinations. While these tests have been widely applied in clinical practice, there is considerable variation in arm positioning within each clinical examination.

Hypothesis: To determine the ideal arm and shoulder positions for isolating the subscapularis muscle while performing the bear-hug, belly-press, and lift-off tests.

Study Design: Controlled laboratory study.

Methods: The activity of 7 muscles was monitored in 20 healthy participants: upper and lower divisions of the subscapularis, supraspinatus, infraspinatus, latissimus dorsi, teres major, triceps, pectoralis major. Electromyogram data were collected and compared across each clinical test at varying arm positions: bear-hug (ideal position, 10° superior, 10° inferior to the shoulder line), belly-press (ideal position, maximum shoulder external rotation, and maximal shoulder internal rotation), and lift-off (ideal position, hand position 5 in. [12.7 cm] superior and 5 in. [12.7 cm] inferior to the midlumbar spine).

Results: Regardless of arm and shoulder position, the upper and lower subscapularis muscle activities were significantly greater than all other muscles while performing each test. No significant differences were observed between the upper and lower subscapularis divisions at any position within and across the 3 tests. There were no significant differences in subscapularis electromyogram activities across the 3 tests.

Conclusion: The level of subscapularis muscle activation was similar among the bear-hug, belly-press, and lift-off tests. The 3 tests activated the subscapularis significantly more than all other muscles tested but were not different from one another when compared across tests and positions. Although the bear-hug and lift-off tests have been described to activate differential portions of the subscapularis, the findings of this study do not support the preferential testing of a specific subscapular division across the 3 tests. As such, all 3 tests are effective in testing the integrity of the entire subscapularis muscle, although there does not appear to be an ideal position for selectively testing its divisions.

Clinical Relevance: Clinicians may feel comfortable in using any of the 3 tests, depending on the patient, to isolate the function of the subscapularis as a single muscle. Furthermore, clinicians should not solely focus on a patient’s arm position when administering an examination but also compare the affected arm to the contralateral shoulder when appropriate.