Novel Approach to Skydiving after Right Hemipelvectomy and Left Hip Disarticulation

Novel approach to skydiving after right hemipelvectomy and left hip disarticulation. Introduction. This is a highly unusual case of a patient with a hemipelvectomy on the right with a hip disarticulation on the left who desired to skydive. The goal for this case was to design a protective seating orthosis, that would be 1. lightweight, 2. dissipate impact forces to protect against dynamic overshoot. 3. It would also need to be relatively compact to allow for aerodynamic stability and not create too much drag. 4. We also desired the prosthesis to be affordable (ie. cost $300 or less). These criteria could be directly opposed to one another and costly. We believe this seating orthosis has broad applications to many patients with severe lower extremity trauma and spinal abnormalities, who wish to have the thrill of a completely solo parachute jump. This technology may have potential to be modified to protect our paraolympic athletes who participate in high impact sports. HPI: This is a 24 year old Caucasian male who presented for evaluation for a right hemipelvectomy with a left hip disarticulation and a large amount of heterotrophic ossification in the soft tissue surrounding his pelvis. He sustained a career ending, near fatal, blast injury, while serving in Afghanistan in 2012. Once he became healthy enough to return to his activities of daily living, he had a strong desire to start skydiving. He made an initial attempt to sky dive with uni-density foam from a commercial furniture store. This resulted in soft tissue injury that was significant enough to required hospitalization. He was very determined to continue skydiving, therefore, his military contacts helped establish a relationship with Dr. Dombroski. Dr. Dombroski has expertise in blast impact helmet technology, along with having served as a flight surgeon for the US army. A team with Dr. Dombroski, his prosthetist and sports medicine fellow worked together to help him achieve his dream of a completely solo parachute flight. Physical examination: He is a pleasant, goal directed 24 year old male. He has normal vital signs. His height is 37 inches and he weighs 66 lbs. He appears alert and oriented. His HEENT, cardiovascular, respiratory,abdominal exams, spine, and upper extremity exam are all within normal limits. On MSK exam his pelvis demonstrates the absence of an ischial tuberosity on the right. In addition to this he has multiple painful pan pelvic soft tissue masses that represent his underlying heterotrophic ossification. His GU exam is significant for the absence of testicles. His psychiatric exam demonstrates a normal affect. He is intelligent and actively involved in online college classes. He is hopeful that he can be a role model for others with disabilities. DDX n/a TEST RESULTS 3D reconstruction of Pelvis FINAL DIAGNOSIS Right hemipelvectomy Left hip disarticulation with heterotrophic bone formation DISCUSSION There have been no case reports to our knowledge that report on solo sky diving after right hemipelvectomy and left hip disarticulation, although tandem jumps have been completed, this is felt to not be as thrilling. This is important as there are many individuals with congenital and acquired lower extremity disabilities that desire to live an active life and this may include solo sky diving. Our goal is to allow them to share in the thrill of solo free fall. Initially, he did provide us with consent to help design this seating orthoses, write this case report and waived all liabilities to all parties involved. He is well aware of the risk involved with skydiving. Dr. Dombroski than attempted to adapt his knowledge of helmet technology to create a helmet for our patients pelvis. The orthoses was made from a multi density foam and placed at a distance of no greater than 5/8ths of an inch from the skin surface. Several trial seating orthoses were produced in the process. These prototypes included a chair with lumbar support and 4 motorcycle springs, a circular snow- sled lined with the multi-density foam, 3D printed ABS plastic shell lined with multi-density foam and finally a 50/50 weave carbon-fiber shell lined with multi-density foam. These seating orthoses were tested using a 40lb sand bag dropped from a height of 7 feet, which represents 60% of our patient's body weight. Prototype 1 did not work secondary to failure to control landing trajectories and being too heavy. Prototype 2 created two much drag and would lead to unsafe parachute deployment. Prototype 3 worked but the plastic failed after multiple drops. Prototype 4 was successful and allowed to be tested as a live jump. Our patient then tested this technology with a successful live jump. Follow up: Our patient has since completed 19 jumps, and he has video-recorded some of them. He continues to encourage and support others with lower extremity disabilities. We are thankful for his service and his willingness to participate in this case report. We were able to meet all 4 of our initial criteria. We believe this technology can be adapted to a wide range of skydiving application to allow patients with severe lower limb injuries, cerebral palsy, spina bifida, and spinal injuries to experience the thrill of solo parachute jumps. It also has the potential to be adapted for our paraolympic athletes who participate in high impact sports. More research is needed in these area as we encourage our amputees to become more active.