Gentamicin Open Tibia Study

Fracture-related infection is a consensus definition of infection after fracture treatment. It is diagnosed by an orthopaedic surgeon based on any of the following four diagnostic criteria: (1) fistula, sinus or wound breakdown; (2) purulent drainage from the wound or presence of pus during surgery; (3) phenotypically indistinguishable pathogens identified by culture from at least two separate deep tissue/implant specimens; or (4) presence of microorganisms in deep tissue taken during an operative intervention, as seen on histopathological examination.

FRI diagnosis is likely to peak between 6 weeks and 6 months after surgery and has a non-normal time-to-event distribution, with incident cases rarely presenting later than 12 months after surgery. All events will be confirmed by an independent adjudication committee comprised of three masked, non-treating orthopaedic trauma surgeons.

Binary outcome based on the following criteria:

• Any unplanned reoperation for promotion of bone healing; OR
• Modified Radiographic Union Scale for Tibia Fractures (mRUST) ≤10 at 12 months follow-up AND either: Function IndeX for Trauma (FIX-IT) score ≤11 at 12 month follow-up, OR recommendation by treating surgeon for nonunion repair surgery

Occurrence of unplanned fracture-related reoperation, a binary variable, for infection, wound healing, or fracture union, excluding removal of implants for prominence/irritation. This may include but is not limited to:

• Irrigation and debridement of surgical incisions or open fracture wounds due to infections or wound healing problems;
• Revision wound closure for dehiscence;
• Soft tissue coverage procedure for infected or necrotic wound;
• Fracture delayed union or nonunion surgery (such as bone grafting or implant exchange);
• Reoperation for hardware or prosthesis failure due to infection or bone-healing problems;
• Amputation for infection, wound or fracture healing problem.

The EQ-5D is a survey instrument that assesses multiple domains of quality-of-life, including mobility, self-care, usual activities, pain/discomfort and anxiety/depression.

The mRUST score is based on evaluation plain radiographs of the fracture site. Each cortex is scored from 1-4 based on the degree of healing and summed resulting in an ordinal scale ranging from 4 to 16, with higher score indicating greater fracture healing.

The FIX-IT score is an ordinal scale from 0-12 that encompasses two domains: ability to weight-bear and pain at fracture site, each scored from 0-6. Higher score indicates more clinical healing.

Suggestive criteria are signs/symptoms of infection that do not meet criteria for definitive fracture-related infection (FRI). These include clinical signs (wound redness, fever) and radiographic signs (sequestrum), elevated serum inflammatory markers, and new onset or increased non-purulent wound drainage.

All serious and non-serious adverse events will be reported as counts for each treatment group

Creatinine is a laboratory value used to assess kidney function. Creatinine levels will be measured preoperatively and 2-days postoperatively for all study participants.