In Vivo Analysis of Biceps Tendon Characteristics in Subpectoral Tenodesis.

Purpose: To report the in vivo characteristics of the long head of the biceps tendon (LHBT); to evaluate the relation of age, gender, height, weight, and body mass index to the length and sutured and tubularized diameter of the LHBT; and to determine the smallest possible tunnel diameter for a subpectoral biceps tenodesis (SPBT) that can accommodate most patients.

Methods: The study included 66 patients (33 men and 33 women) with an average age of 54 years (range, 29-73 years) undergoing SPBT. After tenotomy, the length from the biceps musculotendinous junction to the released end was measured. The tendon was transected 3 cm proximal to the musculotendinous junction and sutured, and the diameter was measured. The depth of the reamed tunnel was recorded.

Results: The average tendon length was 84.0 mm, measuring 91.9 mm in men and 76.2 mm in women (P < .001), and the average tendon diameter was 4.4 mm, varying slightly between men (4.5 mm) and women (4.3 mm) (P < .001). Mean bone tunnel depth was 17.5 mm, with 19 mm in men and 16.1 mm in women (P < .001). Patient height showed a significant relation to both tendon length and tendon diameter. Weight was not correlated with tendon diameter but did show a significant relation to tendon length.

Conclusions: We have characterized the in vivo length and diameter of the LHBT at the time of an SPBT. Our findings have shown that there was a statistically significant gender difference in tendon length and diameter, but the diameter of the sutured tendon, which was placed into the tunnel, averaged 4.4 mm and ranged from 3.5 to 5 mm for all ages, both genders, all heights, and all weights. This finding is clinically relevant in that a small tunnel measuring 5.5 mm or less is sufficient to perform an SPBT.

Level Of Evidence: Level IV, case series, anatomic study.