Chondrolabral defect from recurrent anterior instability, the "Lazarus Lesion"

 Effect of a Chondral-Labral Defect on Glenoid Concavity and Glenohumeral Stability

These authors point out that one of the primary stabilizing mechanisms of the glenohumeral joint is concavity-compression, the maintenance of the humeral head in the concave glenoid fossa by the compressive force generated by the surrounding muscles. This mechanism is active in all glenohumeral positions, but it is particularly important in the functional mid-range in which the capsule and ligaments are slack. The effectiveness of concavity-compression in the stabilization of a joint can be characterized in terms of the ratio between the maximum translation force that can be stabilized in a given direction and the load compressing the head into the glenoid (the stability ratio, see below). 

The illustration below demonstrates the glenoid concavity and the plot of the path of the center of the humeral head as it translates across the glenoid.

They used a cadaver model that enabled the simultaneous measurement of humeral head position and the glenohumeral force - each in 6 degrees of freedom.

The purpose of their investigation was to characterize the concavity and stability ratios of normal cadaveric glenoids, to measure the effect of an anteroinferior chondral-labral defect (see below) on these parameters and to measure the effect of a soft tissue reconstruction.

The chondral-labral defect created in this study reduced the height of the glenoid by approximately 80 per cent and the stability ratio by approximately 65 per cent for translation in the direction of the defect.

Reconstruction of the defect using a tendon graft (see below) restored the normal stability (see above). The stability ratio of the intact shoulder was 38±4%, of the shoulder with the Lazarus Lesion was 13±3%, and the reconstructed shoulder was 47±9%; these differences were all statistically significant.

Today we saw a patient whose x-rays demonstrate the Lazarus lesion (see red L below).

Shoulders with this pathology may not be adequately treated by a Bankart repair alone. On the other hand, procedures such as the Latarjet carry the risk of accelerating the arthritis.

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Here are some videos that are of shoulder interest

Shoulder arthritis - what you need to know (see this link)

The smooth and move for irreparable cuff tears (see this link)

The total shoulder arthroplasty (see this link).

The ream and run technique is shown in this link.

The cuff tear arthropathy arthroplasty (see this link).

The reverse total shoulder arthroplasty (see this link).

Shoulder rehabilitation exercises (see this link).