This project consists of a prospective and retrospective case series design. Study candidates will include all patients 18 years or older, who were evaluated at UCSD and found to have a distal femur or femoral shaft fracture requiring surgical fixation. Patients who consent to study participation will recieve the RFN-advanced Retrograde Femoral Nailing System implant for fracture fixation. Data on functional status, healing rates, complication rates, and pain levels will be collected for each participant. After 3 years of data collection, investigators will analyze this data to provide further insight on the utility of this new design of retrograde femoral nails. Given the relatively high rate of complications, such as malalignment, with current femoral nail designs, it is imperative to evaluate novel systems to appropriately manage distal femur or femoral shaft fractures.

Inclusion Criteria:

• Distal femur or femoral shaft fracture requiring surgery
• Evaluation and treatment at UCSD
• Age 18 years or older
• Ability to understand the content of the patient information/Informed Consent Form
• Signed and dated IRB-approved written informed consent

Exclusion Criteria:

• Any not medically managed severe systemic disease
• their doctor has decided that it is in the patient's best interest to receive a different method of fixation
• Their doctor has determined that the patient has a condition that would make them unsuitable for participation in the study
• Pregnancy or women planning to conceive within the subject participation period (1 year) note: pregnancy will be self-reported and no test will be performed to test for it
• Prisoner
• Participation in any other pharmacologic or medicinal product study within the previous month that could influence the results of this study