Exploring The Potential Of Acellular Dermis Grafts For Wound Healing And Soft Tissue Repair
The long weaves of techniques such as the strip-and-shoelace technique redistribute the tension throughout the weave and help transform the tension force on the graft into a compression force on the tendon much like a braided rope. This not only reduces the tension on the graft strip but also cinches down the thickness of the repair site. This cinching reduces the inherent bulk of the repair site enhancing the ability to close the paratenon or tendon sheath with less tension. (Picture 7) In addition, by having the three separate parts of the repair (primary suturing, inlay strip graft, and woven graft in a shoelace pattern), there are two backup components should one fail.12
Using Acellular Dermis Grafts For Ankle Ligament Repair
Techniques to repair the lateral ankle ligaments using soft tissue grafts have also been described.6 A classic Brostrom primary repair technique is often used to repair the anterior talofibular and calcaneofibular ligaments in a “vest-over-pants” technique. A simple flat onlay of the acellular dermis graft can then be sutured over the repair to enhance the strength). I prefer a more anatomic lateral ankle ligament reconstruction involving an acellular dermis graft strip (e.g. DermaSpan™ in this case) passed through a drill hole in the fibula. A number of authors have described this technique using either a harvested peroneal tendon strip or other grafts (e.g. OrthoAdapt™).6
Locate the anatomic courses of the anterior talofibular and calcaneofibular ligaments. Pass the graft through a drill hole in the fibula placed adjacent to the insertion points of the anterior talofibular and calcaneofibular ligaments to roughly interconnect the two points. Then place the graft over the ligaments and suture it. Soft tissue anchors may strengthen the attachments to bone. (Pictures 8-9).
Soft Tissue Supplementation Procedures
Rocchio describes a “parachute” technique where an acellular dermis graft is placed below the dermis via a small incision approach. This is typically done to augment atrophic subcutaneous tissue (e.g. fat pad) under a bony prominence to reduce pain or prevent recurrent ulceration. A small incision is made adjacent to the prominence. A thick acellular dermis graft is placed below the subcutaneous fat and pulled into place via sutures on the opposite of the margin from the incision. The incision is then closed burying the graft in between the patient’s skin and the bony prominence.23
Key Pointers On Joint Resurfacing And Using Grafts As Joint Spacers
Several authors have described techniques of using acellular dermis grafts in a joint resurfacing application.11 The degenerated articular cartilage is removed and the graft is then placed over the subchondral bone (typically left intact). The graft material acts as an anatomic spacer. Techniques and cases have focused on the first metatarsophalangeal joint with a series of patients showing good long-term success.11 This new area of application would seem to warrant more long-term studies to determine the durability and subsequent incorporation of the grafts, as well as ultimate success in achieving long-term pain relief.