Sunday, February 12, 2017

Reverse total shoulder - the value of the subscapularis

Primary reverse total shoulder arthroplasty outcomes in patients with subscapularis repair versus tenotomy

These authors reviewed 202 patients who underwent primary reverse total shoulder arthroplasties performed by an individual surgeon using the same implant.

At an average follow-up of greater than 3 years, there were on average no significant differences in clinical range of motion, and strength between patients having a subscapularis repair and those not having a subscapularis repair.

There were 0 dislocations (0%) in the subscapularis repair group and 3 dislocations in the no-repair group (2.6%). The first patient’s dislocation occurred while sleeping 4 weeks after surgery. The second patient sustained a dislocation in the first postoperative month while lifting a couch. The third patient sustained a dislocation 10 months after surgery when she was opening a door on a cruise ship and the wind blew the door open with her hand on the handle.

Comment: Initially the surgeon repaired subscapularis tendons that were compliant and could be repaired without significant tension. Then the paper states, "As the primary surgeon progressed in his experience with RTSA using a lateralized design he began routinely leaving the subscapularis as a tenotomy. " It is apparent that the two groups were not concurrent and were not performed on the same part of the surgeon's learning curve. Thus the surgeon's evolution of patient selection and surgical technique as experience was acquired may have influenced the outcomes more than whether or not the tendon was repaired.

As pointed out in this post, Reverse total shoulder - done for instability, yet instability is a major complication dislocation is one of the principal complications of reverse total shoulder including the one used in this study.

Of note is that there were no dislocations among the 86 shoulders having subscapularis repair and three dislocations among the 116 patients without repair.

Our approach to reverse total shoulder (see this link) is to restore the anatomical relationships as much as possible, including, when possible, the repair of the mobilized subscapularis to optimize stability, strength and proprioception. Shown below are the sutures placed in the prepared humerus that will be used for subscapularis repair.