Hello, this is Jocelyn Wittstein from Duke University School of Medicine, and today I'm presenting on hamstring tendon harvest. Specifically, this presentation covers a minimally invasive single-tendon semitendinosis harvest with quadrupled graft using a suspensory fixation technique. The typical landmarks that we utilize in preparing for the semitendinosis harvest include the tibial tubercle and the postterminal border of the tibia, demarcated here in these images. You can typically palpate the two bumps that are representing the gracilis and semitendinosis and judge the positioning of your incision based on the landmarks. Typically the incision is two to three centimeters in length. After sharp dissection is carried down to the pes fascia, I like to utilize a small retractor to palpate the superior border of the sartorius as well as the gracilis and semitendinosis. You can see here I'm palpating the most superior border and then the groove between the gracilis and the semitendinosis. Typically the gracilis is more cord-like and the semitendinosis is broader and flatter, so I make a transverse incision horizontally just below the more cord-like gracilis tendon and just above the broader semitendinosis and then place a hemostat or a tonsil in that split and spread, demonstrate that the gracilis is above and the semitendinosis is below and that deep to the semitendinosis, which is shown retracted in that most inferior picture on the right, we see the MCL fibers that are intact. Once we've identified the semitendinosis, this can be released in a mini hockey stick like fashion, leaving the sartorius and gracilis attachments superior to that intact. We can then fold that over towards ourselves and place a tonsil between the semitendinosis tendon as well as the overlying sartorial fascia and then release the sartorial fascia off the backside of that instrument to give us this free end of the semitendinosis tendon. Subsequently, accessory insertions are identified. Typically, I do this with the right angle that I can then place under each accessory insertion and pull it towards the incision where I can then release these one by one until the tendon is mobilized such that we can freely pull it into the wound without puckering of the skin at the posterior medial aspect of the knee. At this point, a double luggage tag needleless suture loop is placed around the tip of the tendon and this is useful when we are controlling the tendon as we harvest it with the stripper and this will be removed at the time of graft preparation so we don't need to place any additional needle passes through the tendon. At this point, the edge of the tendon is grabbed with a tonsil in addition to the suture that we placed and then maximally rolled to us so that we have as much length of the tendon as possible outside of the wound and then the stripper is used in line with the tendon which is then held under tension. I typically use a closed tendon stripper. This helps us avoid any early graft amputation by again having it under tension as much length of it out of the wound as possible. On the back table, we can cut the graft at 270mm. We definitely don't need any more length than that. We do want a minimum length of 245mm to allow us to have the minimal length for the quadrupled graft. I prefer the graft to be 65mm in length once quadrupled but in a small individual with a length of 235mm, we'll accept something shorter, closer to 60mm. The muscular tissue is stripped using either a metal ruler or the osteotome. The graft is then secured to tensioning suture loops with a button and tensioning suture loop on the femoral side and tensioning suture loop for the tibial side. The graft is wrapped essentially through the tensioning suture loops until it is quadrupled And on the picture on the right here, you can see the two free ends that are not yet secured to make this a continuous loop. These are then secured using a horizontal mattress suture, and you can see in the image on the right what the continuous loop of the quadruple tendon looks like secured to the tensioning suture loops on each side. At this point, we place cerclage sutures that enter and exit between the graft limbs, typically two on each side. The suture tails are tied and then dunked centrally and cut. You can see in this video here that the cerclage suture does go around the graft one and a half times, entering between two strands of the graft, wrapping around one and a half times, and then going from the outside in such that the suture will exit centered between all the limbs. Once the graft is complete, having placed four cerclage sutures, we can mark our interosseous distance on the tensioning suture loop. The graft can be sized on each end. If you're using a complete tibial tunnel, it can be helpful to leave the femoral loop longer, marking the interosseous distance on the loop, and that way you can watch the button go up and out the femoral socket and engage on the external aspect of the cortex while viewing from the medial portal. If you're using the quadrupled semitendinosus graft for an all-inside ACL technique, it can be helpful to shorten the femoral loop to the interosseous distance on the femur such that when you pull the graft in through the medial portal, you know that as soon as the graft engages the opening to the tunnel inside the knee, that the button can then be engaged on the femoral cortex. The quadrupled semitendinosus graft is useful with this tensioning suture loop on the tibia. It typically is secured with a button that can be loaded onto these tensioning suture loops, and then this can be tensioned onto the tibia, plus or minus the addition of backup fixation such as an anchor to further secure these suture tails.

minimally invasive

hamstring tendon harvest

quadrupled graft

suspensory fixation

ACL reconstruction

semitendinosus harvest

cerclage sutures