Shifting the paradigms for complex shoulder surgery

For patients with complex shoulder problems involving paralysis and instability, treatment options have been sparse. Mayo Clinic is pioneering new surgical techniques — muscle transfers that can restore some deltoid function as well as tendon transfers for massive rotator cuff tears, brachial plexus injury (BPI), trapezius paralysis and subscapularis tears — that provide options for patients with debilitating shoulder conditions.

"Mayo Clinic can manage very complex cases that often cannot be treated elsewhere," says Bassem T. Elhassan, M.D., a consultant in Orthopedic Surgery at Mayo Clinic in Rochester, Minnesota. "When a patient has multiple problems with instability, bone defects and muscle paralysis, we are able to perform not only implantation and bone grafts but also complex transfers of muscles and tendons to restore shoulder function."

Re-creating the deltoid

Reverse shoulder arthroplasty is contraindicated in patients with deltoid paralysis, as the implant's biomechanics and stability require a functional deltoid. Thus, surgical treatment options for patients with arthritis and deltoid paralysis have been limited.

Dr. Elhassan and colleagues have developed a procedure for reverse shoulder arthroplasty that transfers a pedicled pectoralis muscle to reconstruct the anterior deltoid. Local tendon transfers can be performed in addition to provide shoulder rotation.

"This surgery gives improved shoulder function to patients who have been told that there's no solution to their problems. It is a procedure done only at Mayo Clinic," Dr. Elhassan says.

In a study to be published in the Journal of Shoulder and Elbow Surgery, Mayo researchers found that among 31 patients who had reverse shoulder arthroplasty and a pedicled pectoralis transfer, 29 had significant improvement of pain, shoulder subjective value, and Disabilities of the Arm, Shoulder and Hand (DASH) score. Flexion improved to a mean 83 degrees and external rotation to a mean 15 degrees.

"This procedure re-creates the anterior deltoid in a close-to-anatomic fashion," Dr. Elhassan says.

Solutions for severe rotator tears and BPI

Standard treatments for irreparable rotator cuff tears and for BPI often result in minimal or no improvement. Mayo Clinic's innovation — lower trapezius transfer — has demonstrated effectiveness for both conditions.

Among 33 patients with a symptomatic massive irreparable rotator cuff tear who underwent lower trapezius transfer at Mayo, 32 had significant improvements in pain and function, according to a study published in the August 2016 issue of Journal of Shoulder and Elbow Surgery. Improvements were documented in patients' DASH scores and in flexion, abduction and external rotation. The Mayo procedure included Achilles tendon allograft to reinforce the lower trapezius.

"Although patients with greater than 60 degrees of preoperative flexion had more significant gains in range of motion than other patients in the study, all patients had improved shoulder external rotation, regardless of their preoperative loss of motion," Dr. Elhassan says.

Among 12 patients with severe BPI who underwent a new Mayo Clinic procedure — contralateral lower trapezius origin transfer (CLTOT) — 10 improved from no shoulder external rotation motion preoperatively to an average external rotation of 110 degrees from the abdomen.

A report of these treatments in the April 2016 issue of the Journal of Hand Surgery noted improvements in patients' Constant shoulder scores, simple shoulder values and DASH scores. None of the patients studied had changes in contralateral shoulder function and strength after surgery.

Five of the 12 patients had additional tendon transfers to manage painful symptomatic inferior shoulder subluxation in the absence of shoulder abduction-flexion. "These additional transfers have been shown to have no direct functional consequences for external rotation, so any gains in shoulder rotation would be due to the lower trapezius transfer," Dr. Elhassan notes.

Improved surgery for trapezius paralysis

The Eden-Lange procedure, described in the first half of the 20th century, has been the standard approach for patients with trapezius paralysis who don't respond to conservative treatment. But the original Eden-Lange procedure potentially creates an internal rotation torque on the chest wall instead of the trapezius's normal external rotation torque.

To re-create the trapezius's line of pull, Mayo Clinic orthopedic surgeons have modified the Eden-Lange procedure. Mayo's triple-tendon (T3) transfer involves transferring the levator scapulae, rhomboid minor and rhomboid major, including all muscles' bony insertions.

A study of T3 transfers in 22 patients with a history of persistent trapezius paralysis secondary to spinal accessory nerve injury showed the procedure is effective in stabilizing the scapulothoracic articulation and restoring trapezius function. As reported in the August 2015 issue of the Journal of Shoulder and Elbow Surgery, winging was corrected in all patients. In addition, all patients had significant improvement of pain and range of motion, including active shoulder abduction and shoulder flexion.

"The main reason for these good outcomes with T3 transfer is the ability to restore the line of pull of the trapezius. Careful rehabilitation also is important," Dr. Elhassan says. "The levator scapulae, rhomboid major and rhomboid minor are much smaller than the trapezius, so it's critical to allow time for full healing of the transfer before strengthening begins."

Subscapularis breakthrough

Laboratory research is the foundation for Mayo Clinic's surgical innovations. A cadaveric study described in the April 2014 issue of the Journal of Shoulder and Elbow Surgery demonstrated the feasibility of transferring latissimus dorsi or teres major tendons or both to reconstruct irreparable subscapularis tears, paving the way for better outcomes than achieved with the typical approach of pectoralis major transfer.

"At Mayo we have incredible access to the Motion Analysis Laboratory, where we can do research on a biomechanical or anatomic level that allows us to say that a new procedure is possible," Dr. Elhassan says. "The best part of Mayo is the teamwork that ultimately benefits patients."

For more information

Elhassan BT, et al. Outcome of reverse shoulder arthroplasty with pedicled pectoralis transfer in patients with deltoid paralysis. Journal of Shoulder and Elbow Surgery. In press.

Elhassan BT, et al. Outcome of lower trapezius transfer to reconstruct massive irreparable posterior-superior rotator cuff tear. Journal of Shoulder and Elbow Surgery. 2016;25:1346.

Elhassan BT, et al. Contralateral trapezius transfer to restore shoulder external rotation following adult brachial plexus injury. Journal of Hand Surgery. 2016;41:e45.

Elhassan BT, et al. Outcome of triple-tendon transfer, an Eden-Lange variant, to reconstruct trapezius paralysis. Journal of Shoulder and Elbow Surgery. 2015;24:1307.

Elhassan BT, et al. Feasibility of latissimus and teres major transfer to reconstruct irreparable subscapularis tendon tear: An anatomic study. Journal of Shoulder and Elbow Surgery. 2014;23:492.