Role of the long head of the biceps brachii muscle in axial humeral rotation control

Abstract

This anatomical and biomechanical study focuses on the specific influence of the long head of biceps brachii muscle in controlling axial humeral rotation. The tendon of the long head of the biceps brachii (biceps tendon) is shown to either facilitate or restrict axial humeral rotation. Its effect on axial humeral rotation is strongly related to firstly the amount of biceps tendon load, secondly glenohumeral scapular plane elevation, and thirdly the rotatory position of the humerus. At 0° glenohumeral elevation, biceps tendon load caused an increase of internal humeral rotation, from 0° at 2.25 N biceps tendon load to 23° at 82.25 N. Under 45° glenohumeral elevation, biceps tendon load can restrict and facilitate as well internal and external axial humeral rotation, increasing the rotatory range of motion. Above 45° glenohumeral elevation biceps tendon load restricts internal and external axial humeral rotation, increasing actively joint stability by increasing torsional rigidity. These findings on the function of the biceps tendon could have consequences for the clinical interpretation. In the elevated arm position, extreme rotation loads the long head of the biceps tendon and may turn out to biceps or bicepslabrum complex injuries.

Treatment outcomes of tendinitis of long head of the biceps brachii tendon by different surgeries based on the concept of enhanced recovery after surgery

“…Since both LHBT tenodesis and tenotomy eliminate any effect stabilizing the shoulder, similar results can be obtained after the two procedures. [ 28 - 30 ]…”

“…Since both LHBT tenodesis and tenotomy eliminate any effect stabilizing the shoulder, similar results can be obtained after the two procedures. [28][29][30] Recently, it has been found by postoperative magnetic resonance imaging (MRI) that the incidence rate of rotator cuff retear has no significant difference after LHBT tenodesis and tenotomy. In a prospective randomized-controlled trial, Lee et al [31] found through MRI at 12 months after the operation that 80.4% of the biceps tendon was still in the bicipital sulcus in the tenotomy group.…”

Assessment of the Preserved Biceps Tendon After Arthroscopic Rotator Cuff Repair in Patients ≤ 55 Years

“… 8 It has been reported that patients who underwent rotator cuff repair with biceps tenodesis showed earlier pain relief than patients without LHBT treatment. 9 On the other hand, it has been reported that LHBT works as a stabilizer of the humeral head 10 , 11 and that loss of LHBT was associated with a small increase in superior translation of the humeral head. 12 According to these findings, we have been preserving the LHBT only when a shoulder with a medium-sized or smaller tear showed no hypertrophy of the extra-articular LHBT and no or mild vascularity in the bicipital groove on preoperative ultrasonography.…”

Biomechanical characterization of unicortical button fixation: a novel technique for proximal subpectoral biceps tenodesis

“…Testing was performed at room temperature, and desiccation was prevented by treating the specimens with 0.9 % saline. The tendons were preloaded to 10 N and then underwent cyclic loading between 10 and 60 N for 200 cycles at 1 Hz [4, 13, 41, 42, 50]. An axial load was then applied at 1 mm/s until failure.…”