An open fracture is a 60-minute problem before it is an orthopedic one. Bone that has broken through skin carries bacteria into the wound the moment it happens, and every 60 minutes of delay adds contamination that no antibiotic fully undoes. Cover the wound, cover the bone end, cover the whole limb, and be at a clinic inside 1 hour. There are exactly 3 things to do and 0 bones to push back.
60 minutes, 3 covers, 0 reductions
The clock starts at the injury, not at the clinic. A cat with an open tibia or radius fracture that reaches surgery within 6 hours has a much lower infection rate than one that arrives at 24 hours, and the difference in outcome is often a limb. Do not spend 20 minutes looking for a vet who is open: call the nearest 24-hour hospital, say open fracture, and ask whether they have orthopedic cover tonight. If the answer is no, they will still stabilize and refer, which is faster than driving 90 minutes to the right specialist first.
The 3 covers, in order
First cover the wound: a sterile gauze soaked in saline, or the cleanest cloth in the house, pressed over the opening for 3-5 minutes. Do not flush it with alcohol, hydrogen peroxide or iodine; those 3 kill tissue and push the infection deeper. Second cover the bone end: lay gauze over the exposed bone and leave it there, because a bone end that dries out in 15-20 minutes loses the surface that a surgeon can clean. Third cover the limb: wrap 3 layers, padding then dressing then a light outer bandage, and splint the leg in the position you found it, splinting 1 joint above and 1 below the break.
What never to do on the way
Never push the bone back under the skin. A bone end that goes back in carries dirt, hair and cloth with it, and a closed fracture with that inside is worse than an open one. Never pull the limb straight to make it look better; a 2 cm overlap is a surgical problem, but a torn artery from traction is a dead limb. Never wrap tight: the wrap should admit 1 finger under it, and a toe that does not pink up within 2 seconds of pressing means the bandage comes off, not that it needs another layer. Never use a tourniquet; a cat has under 100 mL of blood in a hind limb and 15 minutes of a tight band costs the leg. Never give ibuprofen, acetaminophen or aspirin, never feed the cat in case it needs anesthesia in the next hour, and never let it lick the wound, because a cat's mouth adds Pasteurella to an already dirty fracture.
The 0-1-2-6-24 hour timeline
| Hour | What you can measure | What has to happen |
|---|---|---|
| 0 | Bone visible, bleeding under 20 mL, gum color pink, HR 180-220 | 3 covers, carrier, call the clinic, no food |
| 1 | Arrive within 60 minutes; pain score, pulse in the foot | IV opioid, wound swab, tetanus status, radiographs |
| 2 | 2 radiographic views, 1 above and 1 below the joint | Lavage with 500-1,000 mL saline, debridement |
| 6 | Wound clean, blood loss under 20 mL, HR 150-180 under anesthesia | Repair or external fixator, or a planned second look at 48 hours |
| 24 | Swelling, drainage, temperature 38.1-39.2 C | Recheck bandage, culture result at 48 hours, antibiotics reviewed |
Two of those rows decide the limb: hour 1, when the wound is covered, and hour 6, when it is cleaned. Everything between them is transport and pain control.
2 antibiotic classes, prescription only
Open fractures get antibiotics, but which one and at what dose is a veterinary decision, not a pharmacy one. The 2 classes used most often are a first-generation cephalosporin (cefazolin), given intravenously in hospital, and amoxicillin-clavulanate, given by mouth after surgery. Both require a veterinary prescription; the dose and the interval are set by the vet on the cat's weight, not copied from a human label or a forum. Never use leftover human antibiotics, never use a fish or bird product, and never start a course before the wound has been swabbed, because 24-48 hours of a random drug turns a useful culture into a negative one.
What the clinic does in the first 6 hours
The first 10 minutes are about shock, not the leg: gum color, heart rate, and whether the cat responds. Then 2 radiographic views, always 2 because 1 view hides a second fracture in 10-20% of cases. Wound lavage uses 500-1,000 mL of saline at low pressure, and debridement removes any bone fragment that has lost its blood supply. Repair happens in the first 24-72 hours depending on swelling: a pin and wire, a plate, or an external fixator with 2-4 pins. A cat with an open fracture typically stays 2-4 days, and the bandage is changed every 24-48 hours for the first 3 changes.
What changes the outcome
Time is the biggest factor, then contamination. A clean break from a fall, covered in 5 minutes and cleaned at hour 2, does well. A fracture from a dog bite, with crushed muscle and Pasteurella already inside, needs 2-3 surgeries and 4-6 weeks of antibiotics, and 10-30% of those limbs are eventually amputated. Smoking at home slows healing, and a cat that licks through its bandage in the first 48 hours undoes 3 weeks of repair. If the cat was outdoors when it happened, ask about toxin exposure too: a cat that fell and then chewed a lily leaf has 2 problems, and the toxin checker is faster than a phone call at 2 a.m.
Splinting is a holding action, not a treatment
If the clinic is more than 60 minutes away, a temporary splint is worth the 5 minutes it takes, and the rules are in the splint guide: 1 joint above, 1 below, 3 layers, and a finger-width gap. What a splint must never do is hide the wound, so cut the padding away from the opening and keep the gauze visible. Recheck the toes every 30 minutes: cool, pale or slow to pink up means the wrap is too tight.
5 steps for the next 10 minutes
- Cover the opening with saline-soaked gauze and press for 3-5 minutes.
- Lay gauze over the bone end and leave it; do not push the bone in.
- Pad, wrap and splint the limb as it lies, with 1 finger of slack.
- Call the nearest 24-hour hospital, say open fracture, and ask for orthopedic cover.
- Transport flat in a carrier, keep the cat at 20-24 C, and bring the cat's weight in kg.
Frequently asked
Should I push the bone back in before the vet sees it?
No, never. Pushing the bone end back under the skin drags dirt, hair and cloth into the wound and turns a contaminated open fracture into a contaminated closed one, which is harder to clean. Cover the bone end with gauze and leave it exactly where it is, even if it looks wrong, and let the surgeon decide at hour 1 or 2.
Can I give my cat a human painkiller for the fracture?
No. Ibuprofen causes kidney failure in cats and acetaminophen destroys hemoglobin, and both are toxic at a fraction of a human dose. Aspirin also interferes with clotting and with the drugs used in surgery. Keep the cat quiet in a carrier, call ahead so an opioid can be ready on arrival, and give nothing by mouth in case anesthesia is needed within the hour.
Why do antibiotics need a prescription for an open fracture?
Because the drug, the dose and the timing all change the outcome. The 2 common choices are cefazolin, a first-generation cephalosporin given intravenously in hospital, and amoxicillin-clavulanate by mouth after surgery; both are prescription-only and dosed by weight. A random leftover tablet given before the wound is swabbed can also make the culture negative.