After a broken kneecap (patella fracture), most people are back to normal daily activities in about 3 to 6 MONTHS. Thigh strength takes longer, and some people notice a weaker leg for a year or more.
The first weeks are spent with the knee held STRAIGHT in a brace. In most cases you can walk on the leg in the brace, with crutches. The bend is then unlocked a little at a time, usually over about 6 weeks.
How long the brace stays locked and how fast the bend opens up is your surgeon’s call. Follow their protocol over any timeline here.
Surgery or no surgery?
- No surgery: when the pieces haven’t separated and you can still lift your straight leg off the bed. A brace or cast holds the knee straight while the bone heals, usually for several weeks
- Surgery: when the pieces have pulled apart, the joint surface behind the kneecap has a step, or you can’t lift your leg straight. The thigh muscle pulls through the kneecap to straighten the knee, so a gap has to be closed for the leg to work
- How it’s fixed: wires, pins, screws, strong stitches or a small plate. If one part is shattered into small pieces, it may be removed and the tendon reattached to the rest of the kneecap
- The leg-lift test: lifting your straight leg shows the surgeon the muscle, kneecap and tendon are still working as one. It’s one of the first things they check
Recovery timeline after surgery
- Weeks 0 to 2: brace locked straight, crutches, and the leg raised when you rest. Many surgeons let you put as much weight through the leg as is comfortable while the brace is locked. See weight bearing after surgery. Your team will talk to you about preventing blood clots
- Around week 2: wound check. In many protocols gentle bending starts now, often to about 30 degrees
- Weeks 2 to 6: the brace is unlocked in steps, commonly about 30 degrees more every 2 weeks, reaching about 90 degrees somewhere around 6 weeks
- Weeks 6 to 12: the brace comes off once your thigh muscle can control the knee, and the crutches go once you walk without a limp. Stationary bike, sit-to-stands and step-ups
- Months 3 to 6: most people are back to normal daily activities. Strength work gets heavier. Running usually not before about 4 months, and only once you’re cleared
- Months 6 to 12: return to sport, usually not before 6 months, once strength is close to the other leg
The straight-leg weeks
- Why straight: bending the knee pulls the kneecap pieces apart. Keeping it straight takes that tension off while the bone knits
- It isn’t bed rest: you can usually walk in the locked brace. Getting up and about helps the swelling and lowers clot risk
- Wear it as told: most people sleep in the brace for the first weeks. Ask your team when it can come off for washing
- Don’t unlock it early yourself: less pain doesn’t mean the bone is ready for bending
The kneecap heals in weeks. The thigh muscle takes months.
Getting your thigh strength back
- Start on day one: tighten the thigh muscle by pushing the back of the knee down into the bed. Hold 5 seconds, 10 times, several times a day
- Straight leg raises: in the brace, lift the leg a few inches off the bed. The first goal is lifting it without the knee sagging
- Then build: sit-to-stands, step-ups, mini squats and leg press, as your physio allows
- Keep going after physio ends: the thigh muscle shrinks fast after a knee injury, and some people are left with lasting weakness. A short strength routine a few times a week protects the knee for the long run
What’s normal, and the longer term
- Pain when kneeling: very common, and it can last many months or longer
- A numb patch beside the scar, which usually shrinks over time
- Swelling after a busy day for several months
- Wires or pins you can feel: they sit just under the skin. About 1 in 3 people have them taken out later because they rub or ache. That’s a smaller operation, done once the bone has fully healed
- Arthritis later: the back of the kneecap is joint surface, so arthritis behind the kneecap can develop in the years after. See knee arthritis
The American Academy of Orthopaedic Surgeons has a clear guide to kneecap fractures, including the different types and how each is treated. A torn tendon just above or below the kneecap is treated in a similar way.
See quadriceps or patellar tendon rupture. A kneecap that slipped out of place rather than broke is a kneecap dislocation, and a break at the top of the shinbone is a tibial plateau fracture.
Go to the emergency department if
- You have sudden pain or swelling in your calf or thigh
- You have chest pain or sudden shortness of breath
- Your foot or toes go numb, pale, cold or blue
Call your surgeon today if
- The wound is red, hot, swollen, spreading or leaking
- You have a fever or chills, or feel unwell
- You feel a crack or pop, or fall on the knee, and now can’t lift your straight leg the way you could before
Mention it at your next review if
- The knee bends well short of 90 degrees at around 6 weeks
- You still can’t lift your straight leg without the knee sagging when the brace is due to come off
- Wires or pins are rubbing or stopping you kneeling
- You’re still limping at 3 months
The brace protects the bone. The strength work gives you your leg back.