Acellular dermis allograft yields good results for massive rotator cuff tears

Wayne Z. Burkhead Jr., MD’s, surgical technique favors acellular dermis to xenograft.

Issue: October 2006

While literature shows poor reactions with xenograft bone substitutes, surgeons are seeking alternatives, such as acellular dermis, for treating massive rotator cuff tears.

A former proponent of xenografts, Wayne Z. Burkhead Jr., MD, of Dallas, now uses acellular dermis because the graft substitute provides all healing elements and maintains vascular channels.

This scanning electron microscope image at 400x demonstrates how the acellular dermis allograft maintains the vascular channels and provides a complete regenerative tissue matrix for all healing elements.

Images: Burkhead WZ

As for other substitutions, “There’s a lot of morbidity from using tissue,” Burkhead said. “[And] freeze-dried bulk allografts … can be very allergenic and autogenic, and they can be rejected.”

The acellular dermis is also cryogenically preserved.

“This cryogenic processing avoids ice crystals, which can create free radicals … which might have your graft resorbed,” he said. “The matrix is a complete matrix, but there are all the elements for healing available. And most importantly, the vascular channels are maintained, and that’s why it seems that this particular product may be better than the others we’ve had before.”

Technique outlined

Burkhead shared his surgical technique for massive rotator cuff tears using the acellular dermis at the 7th Annual Current Concepts in Joint Replacement Spring 2006 Meeting.

Burkhead demonstrated his surgical technique on a man with a large, complex rotator cuff tear and a recently implanted supraspinatus component. He used mobilization techniques to move a chronically stiff infraspinatus component.

“With any type of graft material, you should try to do intra- and extra-articular releases and try to mobilize as much native tissue as you can,” Burkhead said.

In the specific case he presented, Burkhead said the tuberosity was completely extended, so he placed the graft in the sulcus area.

At the start of the repair, Burkhead brought down native tissue to use as a placeholder until healing occurred. He then placed anchor sutures in the teres minor to prepare graft placement.

Acellular dermis grafts have two surfaces: a biologically active peg surface and a smooth surface that should be placed on top, Burkhead said.

“The rotator interval was split all the way over to the glenoid, and we’re going to use this to repair the corner of our tendon back down,” he said. “We then use it as a baseball-type suture along the rotator interval once we get that done.”

Implanting the graft

Burkhead implanted the graft using that same “baseball-type suture.” He attached the graft to the end of the repair interval as a bridge between the vascular musculotendinous junction and the proximal humerus bone and the bursa for blood supply. “We oftentimes soak the graft in the patient’s own blood or use alternatively platelet-rich plasma as an excellent alternative.”

He stressed the importance of tensioning the graft. “It’s hard to know exactly what kind of tension, but if you talk to the manufacturer, about one-third of shrinkage occurs with the hydration process, and so you can use that to kind of calculate the tension,” Burkhead said. The goal: the blood channels should be open and not collapsed, overtensioned or too tight.

Finally, Burkhead doubled the graft, bridging it from the teres minor to the subscapularis. He then placed anchors at the tuberosity to bring the graft down to bone. Closure is typically done by side-to-side repair with the heavy Dacron tape or end-to-end repair with anchors and modern suture material.

Surgeons should be cautious rehabilitating massive rotator cuff tears, he said. “I’ve always put [the shoulders] in an abduction pillow for three weeks and not moved them at all, and then I start some motion above the pillow at 3 weeks,” Burkhead noted. “I’ve been really pleased with the eventual outcome in those.”

This image shows the rotator cuff repair after suturing. Burkhead completed a side-to-side repair with heavy Dacron tape and completed the end-to-end repair with anchors and modern suture materials.

Here, Burkhead re-established the cable effect by doubling the graft and creating a bridge from the terres minor up to the subscapularis.

For more information:
Burkhead WZ. Grafting massive rotator cuff tears: Give me some skin. #19. Presented at the 7th Annual Current Concepts in Joint Replacement Spring 2006 Meeting. May 21-24, 2006. Las Vegas.
Orthopedics Today was unable to determine whether Dr. Burkhead has a direct financial interest in the product discussed in this article or if he is a paid consultant for any companies mentioned.