Purpose: We examined the long-term effect of the Latarjet-Patte procedure on subscapularis function and trophicity.

Material and methods: The series included 102 patients (106 shoulders) reviewed at a mean follow-up of 7.5 years. The subscapularis was opened by dissection along the direction of the fibres in 27 shoulders (group I) and via inverted-L tenotomy in 69 (group II). Duplay and Rowe scores were used to assess clinical outcome. Subscapularis function was measured with the hand-back distance and the Gerber lift-off test in comparison with a control group composed of healthy subjects in order to account for limb dominance. Computed tomography was used to measure fatty degeneration and muscle atrophy.

Results: The Duplay and Rowe scores gave 76.4% and 87.7% satisfactory results. The Duplay score was 89.9/100 in group I and 82.1 in group II (p = 0.02). The hand-back distance and muscle force as judged by the lift-off test were statistically different between the dominant and non-dominant sides (p = 0.001). Loss of muscle force was greater for dominant sides in the operated shoulders. The mobility score, the lift-off test, and the hand-back distance were significantly altered in group II patients. Fatty degeneration of the sub-scapularis was greater on the operated side (0.76 vs 0.054) (p = 0.001). It increased with age at surgery and at review (p = 0.0001), for dominant shoulders in group II (1.18 vs 0.12). It affected the Duplay score (p = 0.006), the hand-back distance, and the lift-off test (p = 0.01). Fatty degeneration was greater than 2 in 66% of the shoulders with a poor outcome and persistent apprehension in 35.3%. Subscapular atrophy was greater on the operated side (0.91 vs 1.17) (p = 0.0001) and was statistically correlated with fatty degeneration, the Duplay score, the lift-off test, and the hand-back distance. It was greater in group II (0.71) than in group I (0.2).

Discussion: Recovery of muscle force is better for dominant shoulders. Muscle trophicity and function are influenced by subscapular tenotomy that leads to significant loss of internal rotation force, atrophy, and fatty degeneration affecting final long-term outcome.

Conclusion: We recommend discission of the subscapularis for coracoid bone block procedures.