The Use of a Dynamic Sustained Compression Intramedullary Nail for Tibiotalocalcaneal Arthrodesis
The Use of a Dynamic Sustained Compression Intramedullary Nail for Tibiotalocalcaneal Arthrodesis
The purpose of this study is to determine the clinical efficacy of a novel sustained dynamic
 compression intramedullary nail for tibiotalocalcaneal (TTC) arthrodesis utilizing
 longitudinal weight-bearing computed tomographic imaging. Of particular focus will be
 assessment of compressive element recovery and its relation to fusion development over time
 and weight-bearing status. Additionally, the study will incorporate longitudinal fusion
 assessment to evaluate differences between three-dimensional weight-bearing computed
 tomography (WBCT) scans and two-dimensional radiographs (X-rays) at multiple points of the
 fusion process. Finally, the study will evaluate the differences in WBCT-based fusion
 assessment between automated and manual methodologies for fusion area calculation.
This study is a collaborative effort between the Orthopedic Foot and Ankle Center, MedShape,
 Inc, and CurveBeam. This is a prospective investigation to assess the clinical outcomes of
 patients with a tibiotalocalcaneal arthrodesis with the Sustained Dynamic Compression
 Intramedullary Nail (DynaNail), including longitudinal assessment with weight-bearing CT. The
 investigators plan to enroll 45 patients. No placebo control will be used, as there is no
 other IM nail available capable of providing sustained compression. Additionally, given that
 many patients receiving this treatment have had prior failed treatments and face poor
 alternatives such as amputation, using a prior-generation IM nail as a control treatment
 would be unethical.

 Design:

 This is a prospective, single-group study. Patients of the Orthopedic Foot and Ankle Center
 who are scheduled to undergo TTC arthrodesis will be screened for eligibility and informed
 consent will be obtained from those who meet the inclusion/exclusion criteria. Subjects will
 be assessed pre-operatively and then at five post-operative intervals: 1 week, 6 weeks, 3
 months, 6 months, and 12 months. A WBCT scan will be obtained at each interval.

 Selection of Subjects:

 Patients will be identified in the clinic by an attending orthopaedic foot and ankle surgeon
 or his/her physician assistant based on clinical exam and radiographic findings. Patients
 will be screened for eligibility by the research coordinator/ key personnel in close
 coordination with the surgeon and co-investigator.

 Pre-operative Questionnaire:

 After informed consent, the patients will be asked to complete patient reported outcomes
 questionnaires that are part of the SOS Registry associated with function and pain, including
 VAS, VR-12, FFI-R, FAAM, AOS, and AOFAS. The patients will also be asked to provide
 information related to prior medical history (including potential co-morbidities associated
 with non-union, i.e. tobacco usage, neuropathy, renal disease, obesity, etc.) and surgical
 history of the subject lower extremity.

 Surgery:

 The following surgical procedure is standard of care. The surgical procedure will involve
 both tibiotalar and talocalcaneal joint preparation through any approach (lateral, posterior,
 anterior with sinus tarsi). The use of supplemental bone graft is at the discretion of the
 treating surgeon but must be documented. The MedShape DynaNail will then be inserted
 according to the manufacturer's technique. The patient will be placed in a short leg splint
 and kept non-weight bearing initially. The patient will be discharged from the hospital when
 medically ready. Weight-bearing will start at seven weeks post-surgery.

 Follow-Up Visits and Questionnaires:

 The patient will return to clinic for visits at the following intervals after surgery: 1
 week, 6 weeks, 3 months, 6 months, and 12 months. At each of these time points, a clinical
 exam will be conducted, and SOS patient questionnaires will be administered, as well as a
 radiographic and clinical follow-up form. Additionally, radiograph and weight-bearing CT
 imaging will be obtained of both the ankle and subtalar joints. At 3 months and 12 months
 post-op, all X-ray and CT images will be de-identified, burned to a DVD, and copies will be
 sent to both co-sponsors.
Inclusion Criteria:

 -  Meets indications for TTC arthrodesis and receives the DynaNail implant

 -  Able to understand the requirements of the study

 -  Willing to comply with the study protocol

 -  Sign an Informed consent

 -  18 years of age or older

 Exclusion Criteria:

 -  Investigator determines that the subject is unlikely to comply with the requirements
 of the study

 -  Non-English speaker

 -  Blind

 -  Illiterate

 -  Prisoner