Summary

Preoperative MRI assessment of cartilage loss, subchondral signal, and abnormal signal in the long head of the biceps tendon can be useful for diagnosing biceps chondromalacia and, more importantly, in identifying underlying biceps-labral complex disease even prior to gross visualization of biceps chondromalacia intraoperatively.

Abstract

Purpose

The purpose of this study was to assess the ability of preoperative MRI to identify Biceps Chondromalacia (BCM), a lesion on the humeral head resulting from chronic abrasion of the humeral head by the Long Head of the Biceps Tendon LHBT.

Methods

This study is a retrospective review of prospectively collected data. Patients were categorized into three different groups based upon intraoperative findings.  Group 1: underwent a biceps procedure for chronically symptomatic Biceps Labrum Complex BLC disease, with BCM (n=34) at arthroscopy. Group 2: underwent a biceps procedure for chronically symptomatic BLC disease without BCM at arthroscopy (n=21 pts).  Group 3: underwent an arthroscopic anterior stabilization for traumatic instability, and did not have any clinically evident BLC pain (n=29). Presence or absence of BCM was prospectively scored in a binary fashion by the operating surgeon.  MRI’s were retrospectively evaluated by a musculoskeletal radiologist, blinded to intraoperative findings or group assignment for rotator interval scarring, adhesive capsulitis, chondral loss, bone marrow edema, and subchondral signal change in the two regions of BCM as well as proximal long head of the biceps tendon signal change.

Results

Significant differences were identified among the three groups for loss of cartilage and subchondral signal change in the defined regions of interest, as well as proximal biceps signal. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for MRI to predict BCM based on surgery as the standard was 61-82%, 33-57%, 51-56%, and 58-67% respectively. No significant differences were identified between the groups with symptomatic BLC (Groups 1 & 2) based upon MRI findings; 85-86% (29 out of 34 patients and 18 out of 21 patients, respectively) of patients demonstrated cartilage loss and 81-85% (29 out of 34 patients and 17 out of 21 patients, respectively) demonstrated LHBT signal abnormalities. These findings differed significantly from Group 3, who showed such abnormalities at 52% (15 out of 29 patients) and 45% (13 out of 29 patients) respectively. MRI evidence of cartilage loss, subchondral signal change, and abnormal LHBT signal predicted the presence of BLC disease resulting in sensitivity, specificity, PPV, and NPV of 60-86%, 48-66%, 76-78%, and 46-64% respectively.

Conclusion

Preoperative MRI assessment of cartilage loss, subchondral signal, and abnormal signal in the long head of the biceps tendon can be useful for diagnosing biceps chondromalacia and, more importantly, in identifying underlying biceps-labral complex disease even prior to gross visualization of biceps chondromalacia intraoperatively.