Both Single- and Double-anchor Remplissage Techniques Restore Native Stability in a Cadaveric Model of Hill-Sachs Lesions in Anterior Shoulder Instability.

Purpose: To determine the most effective number and location of fixation points for remplissage of Hill-Sachs lesions (HSL) in a cadaveric model of anterior shoulder instability.

Methods: Eleven fresh-frozen cadaveric shoulder specimens were tested. A robot device tested resistance to anterior translation of the humeral head. Eleven shoulder conditions were tested: (1) intact, (2) 15% HSL, (3) 15% HSL with 1 central, (4) 15% HSL with 2 central, (5) 15% HSL with 1 medial, (6) 15% HSL with 2 medial, (7) 30% HSL, (8) 30% HSL with 1 central, (9) 30% HSL with 2 central, (10) 30% HSL with 1 medial, and (11) 30% HSL with 2 medial.

Results: All remplissage techniques tested restored peak resistance to at least equal that of the intact shoulder condition. In the small Hill-Sachs condition, the mean peak resistance for 1 central, 2 central, 1 medial, and 2 medial fixation was 41.5, 52.3, 45.1, and 54.8, respectively. In the large Hill-Sachs condition, the mean peak resistance was 41.7, 59.9, 42.6, and 64.43, respectively. Two fixation points provided more resistance than one in both the medial ( < .01) and central ( < .01) locations. When comparing fixation location, however, there was not a significant difference between 1 central and 1 medial ( > .05) or 2 central to 2 medial ( > .05) in either the large or small HSL.

Conclusions: All remplissage techniques were able to successfully restore mean peak resistance to anterior translation to the native condition in this cadaveric model. There was not a difference in resistance force between medial wall and central placement for either the single- or double-fixation configurations.

Clinical Relevance: This study suggests that one anchor placed either medially or centrally will restore native stability in remplissage for anterior shoulder instability.