Lesions of the biceps pulley: a prospective study and classification update

Abstract

Hypothesis: The purpose of the study was to investigate which anatomic structures are affected in a series of patients with pulley lesions and whether all lesions can be classified according to the Habermeyer classification.

Methods: One hundred consecutive patients with pulley lesions were prospectively studied. During arthroscopy, lesions of the superior glenohumeral ligament (SGHL), medial coracohumeral ligament (MCHL) and/or lateral coracohumeral ligament (LCHL), adjacent rotator cuff, and biceps (long head of the biceps) were recorded. All lesions were then classified according to the Habermeyer classification. The χ² test was used for statistical analysis.

Results: There were 3 lesions in group 1, 20 in group 2, 6 in group 3, and 35 in group 4 according to the Habermeyer classification. Thirty-six lesions were not classifiable because of an intact SGHL. A lateral pulley sling (LCHL) lesion was found in 95% of the patients, and a medial pulley sling (MCHL-SGHL) lesion was noted 64%. An isolated lesion of the MCHL and/or SGHL was present in 5%, and an isolated lesion of the LCHL was found in 36%. Combined medial-lateral sling lesions were correlated with complete subscapularis tears and biceps fraying.

Conclusion: The lateral pulley sling is more often affected than the medial sling. The SGHL is not always affected, and isolated lesions of the medial sling are rare. Lesions of both slings correlated with complete subscapularis tears and fraying of the long head of the biceps. An updated classification of direct pulley lesions is proposed: type 1, lesion of the medial pulley (MCHL and/or SGHL); type 2, lesion of the lateral pulley (LCHL); and type 3, lesion of the medial and lateral pulley slings. Concomitant lesions of the indirect pulley stabilizers can be mentioned additionally according to the well-known classifications.

Keywords: Biceps reflection pulley; biceps instability; biceps tendon injury; pulley lesion classification; pulley lesions; pulley sling.

Figure 1

The biceps reflection pulley is a soft tissue sling consisting of fibers of the superior glenohumeral ligament, coracohumeral ligament, and adjacent rotator cuff fibers (indirect pulley stabilizers). Arthroscopic photographs of a right shoulder show the medial pulley sling, which consists of the superior glenohumeral ligament and medial coracohumeral ligament (A), and the lateral pulley sling, which consists of the lateral part of the coracohumeral ligament (B).

Figure 2

Arthroscopic photographs of a right shoulder showing a type 1 lesion according to the updated classification, that is, an isolated lesion of the direct medial pulley sling. (A) Partial tear of medial pulley sling (medial coracohumeral ligament and/or superior glenohumeral ligament). (B) Intact lateral pulley sling (lateral coracohumeral ligament).

Figure 3

Arthroscopic photographs of a right shoulder showing a type 2 lesion according to the updated classification, that is, an isolated lesion of the direct lateral pulley sling. (A) Intact medial pulley. (B) Torn lateral pulley sling.

Figure 4

(A, B) Arthroscopic photographs of a right shoulder showing a type 3 lesion according to the updated classification with completely torn medial and lateral pulley slings. Fraying (partial rupture) of the long head of the biceps tendon is also noted.

Figure 5

Schema of normal pulley and type 1 lesions according to proposed updated classification system. (A) Normal pulley structures. (B) Type 1 medial pulley sling lesion with torn medial coracohumeral ligament (MCHL). (C) Type 1 medial pulley sling lesion with torn superior glenohumeral ligament (SGHL). (D) Type 1 medial pulley sling lesion with torn MCHL and SGHL. LT, lesser tuberosity; GT, great tuberosity; SSC, subscapularis; Med, medial; CHL, coracohumeral ligament; Lat, lateral; SSP, supraspinatus; LBS, long head of biceps tendon.

Figure 6

Schema of type 2 and type 3 lesions according to proposed updated classification system. (A) Type 2 lateral pulley sling lesion with torn lateral coracohumeral ligament (LCHL). (B) Type 3 medial and lateral pulley sling lesion with torn medial (M) coracohumeral ligament and LCHL. (C) Type 3 medial and lateral pulley sling lesion with torn SGHL and LCHL. (D) Type 3 medial and lateral pulley sling lesion with torn medial (M) coracohumeral ligament, LCHL, and SGHL. LT, lesser tuberosity; GT, great tuberosity; SSC, subscapularis; Med, medial; CHL, coracohumeral ligament; Lat, lateral; SSP, supraspinatus; LBS, long head of biceps tendon.