CAN THE LONG HEAD OF THE BICEPS BE HEALTHY IN ROTATOR CUFF TEARS? EPIDEMIOLOGY AND DYNAMIC BEHAVIOUR

Abstract

Purpose of the study: Injury of the long head of the biceps (LHB) can cause pain in rotator cuff tears (RCT). Our objectives were to:

1. establish an epidemiological database on LHB injuries in RCT;

2. study the dynamic behaviour of LHB in RCT;

3. search for a correlation between injected imaging findings and arthroscopic findings.

Materials and Methods: Prospective, consecutive, multi-centric study (April 2005-June 2006). Inclusion criteria:

1. partial or full-thickness RCT demonstrated arthroscopically,

2. arthorscopic description of LHB,

3. imaging with injection (arthroscan or arthro-MR),

4. data collected on the internet site of the Socité Française d’Arthroscopie (SFA).

Other reasons for arthroscopy, past surgery and MRI were excluded. The dynamic examination consisted in a search for the incapacity to glide the LHB in its gutter during passive abduction of the arm leading to intra-articular fold (hourglass test) and instability of the LHB in its groove during external rotation (medial instability) or internal rotation (lateral instability) with the arm at 90° abduction (RE2 and RI2 tests). Extension of the RCT in the frontal and sagittal plane were determined using the classification of the French Arthroscopic Society.

Results: 378 patients (378 shoulders, 211 women, 167 men, mean age 57.9 years, age range 28–93 years). Arthroscan for 312 shoulders and arthroMR for 66 shoulders revealed 61 partial deep RCT and 317 full-thickness RCT. Among the full-thickness tears, 15 involved the subscapularis (SSc) alone, one the infraspinatus (ISp) alone and 301 the supraspinatus (SSp) alone (with 52 posterior extensions to the ISp, 90 anterior to the SSc and 31 mixted).

Epidemiological data (static test): LHB intact 21%, tenosynovitis 51%, hypertrophy 21%, delamination 12%, pre-tears 7%, subluxation 18%, dislocation 9%, tear 2%. No influence of age, gender or side operated. Conversely, the rate of lesions increased significantly with extention of the RCT in the frontal and sagittal plane.

Dynmaic study: positive hourglass test 29%, instability in RE2 26%, instability in RI2 8%. Hourglass test correlated with intra-articular hypertrophy of the LHB (76% versus 2%). Subscapularis tears lead to medial instability in 82% of cases. Among the 81 shoulders with an intact LBH statically, 17% presented a dynamic anomaly. In all the static and dynamic tests only left 18% of the LHB intact.

Imaging-dynamic arthroscopy correlation: 25% of LHB lesions were not diagnosed by injected imaging. Inversely, there was a good correlation to determine the position of the LHB in its groove.