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Team Members:
  • Rachel An
  • Andrew Jann
  • Matthew Lerner
  • Polly Ma
  • Mohit Singhala
  • Bashir Zikria MD
  • John Wilckens MD
  • Russell Taylor, PhD
  • Soumyadipta Acharya MD, PhD
  • Aditya Polsani, BDS, MS


The anterior cruciate ligament (ACL) is a key ligament in knee function and stability. Over 750,000 people suffer from an ACL tear in the United States every year, and incidence rates are increasing every year. In order to restore the function of the ACL, an ACL reconstruction surgery is performed to replace the torn ACL with a graft. During a reconstruction surgery, the torn ACL is removed so the surgeon can see the original ACL attachment sites on the bone (known as the ACL footprints). Tunnels are then drilled into the femur and tibia bone to make anchor points for the graft. The graft is then passed through the tunnels and fixed in place. 400,000 ACL reconstruction procedures are performed every year in the United States. Of these, 20% fail due to incorrect tunnel placement, resulting in about 57,600 patients who undergo a revision surgery. This amounts to a $360 million cost to the healthcare system each year. For the patients, a failed reconstruction surgery can result in decreased range of knee motion, decreased knee stability, increased rehabilitation time, and for most cases, a revision surgery. As most of these injuries typically occur during physical activity and is more common for teens and adolescents, the return to the original quality of knee function is particularly important. Additionally, when these injuries occur for budding or high-profile athletes, an ACL tear can be especially devastating and has the potential to end a career. With current techniques and tools for ACL tunnel placements, it is difficult for surgeons to reproducibly create anatomical tunnel placements. This is especially true for less experienced surgeons, who perform less than 10 ACL reconstruction surgeries per year. Thus, our team proposes a solution – Orthotract – to provide orthopedic surgeons with a tool that will facilitate more anatomical and reproducible tunnel placements for ACL reconstruction surgeries, in order to reduce failures and revisions.

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