An Entirely New Approach to Tendon Repair
Abstract
Introduction: There is a clear link between particular occupations and an increased risk of hand injury. Combat Soldiers, engineers, mechanic, and manual workers are at particularly high risk of hand injuries, particularly deep cuts and crush injuries from machinery, due to the nature of their occupations. Hand trauma accounts for up to 30% of all patients who are seen in the emergency room; in this group, the tendon is the second most frequently injured structure in the hand. Tendons are strong, smooth cords, like ropes that connect muscles to bone. The flexor tendons are long tendons that connect the muscles in the forearm (near the elbow) to the fingers and thumb and are responsible for the ability of the fingers and thumb to bend. When a person contracts the muscles in the forearm, the tendons pull on the fingers, which enables an open palm to close to a fist. If these tendons are cut, the ability to close the hand and make a fist or to hold an object is lost. Tendons do not have a strong natural capacity to regenerate, which means that surgical repair is essential to their regaining function. Unfortunately, even given modern surgical techniques and technological advances in general, a large volume of patients continue to experience poor recovery due to repairs that fail or to the formation of scar tissue between the tendon and surrounding muscle; this failure ultimately prevents movement. The current recommendation is that tendons be surgically repaired and the patient “exercise” the tendon to prevent scar tissue formation. But a significant problem that persists following surgical repair is that the operation does not provide adequate strength to the repair site and early motion causes sutures to break. This outcome requires a subsequent operation to repair the tendon a second time. If the tendon is not “exercised,” scar formation prevents the full return of function. To improve the hand function of military personnel and civilians alike, there is a critical need for dramatic change in the way tendon repair is approached. Research Proposal: We propose a fundamental shift in flexor tendon repair that will dramatically change the field of tendon and ligament repair, not only the repair of flexor tendons. Despite decades of prior research, outcomes for flexor tendon repair and tendon repair in general remain unpredictable. Our innovative model utilizes pieces of the protective sheath that covers the flexor tendon and are commonly damaged in the trauma or require trimming in surgery to repair the underlying tendon. This tissue would typically be discarded in surgery. We propose that the tissue be re-attached to the tendon itself. We believe that re-attaching this valuable tissue directly over the repair site will redistribute the forces applied to a regenerating tendon that lead to rupture during recovery. Secondly, the addition of the sheath over the repair site will act as a natural barrier, preventing scar formation to the surrounding tissues. We will compare our novel methods to standard surgical repair models in several ways. Initially, testing will be performed in sheep tendons obtained from a butcher, as these tendons are commonly discarded. Before being tested for strength in industrial strength testing machines, tendons will be cut and repaired by either standard surgical procedure or by our novel sheath repair method. Two novel repair methods will be tested: circumferential tendon sheath repair and asymmetric tendon sheath repair. The most effective novel sheath repair method and the strongest standard surgical repair method will be determined from this strength testing and will then be performed in sheep to assess the full recovery of the tendon for future use in humans. Sheep have been selected due to the similarity in size of their flexor tendons to those of humans, as well as the animals’ similar size and weight to those of average adult humans. These animal tests will only be con
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 29, 2018
- Source ID
- W81XWH1810600
Entities
People
- Aaron M Dingle
Organizations
- United States Army
- University of Wisconsin–Madison