Recurrent Anterior Shoulder Instability

Abstract

The purpose of this study was to compare 2 radio graphic methods for measuring anteversion and to de termine whether glenoid anteversion is a significant fac tor in recurrence of instability after anterior repair. West Point axillary roentgenograms were obtained in 128 pa tients (138 shoulders) at a mean of 9 years after sur gery. Two methods to measure glenoid anteversion were compared: The angle between the glenoid and the body of the scapula, and the angle between the glenoid and the posterior margin of the acromion. There was less variation in the measurements using the glenoid margin-posterior acromion angle. By this method, an teversion was 11 ° ± 4° for the 15 patients with multiple (2 or more) recurrences, 8° ± 3° for the 15 patients with 1 recurrence, and 6° ± 5° for the 109 patients with no recurrences. Although these differences are statistically significant (P = 0.003), they probably are not clinically important because they are small (mean of only 5°). The differences obtained by measuring the angle between the glenoid and the body of the scapula were not sta tistically significant.

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References

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