General information only, and not a substitute for medical advice. If you cannot
put weight through the leg, the knee is deformed, or the foot is numb, pale or cold, seek
urgent care today.
Most sore knees after sport or a fall are soft-tissue injuries: a strained muscle, a
sprained ligament, an irritated meniscus. They hurt, they swell, and they settle. But a
proportion are fractures, and in the first day or two the two can look much the same.
The useful question early on is not “is it broken” so much as “does this need imaging
today”. This guide covers what to watch for, what to do in the first 48 hours, and how
that decision actually gets made.
Worried about a knee injury?
Book an assessment online or call
1300 525 666 — Southport and Springwood, no referral needed.
The three symptoms that matter most
You cannot take weight through it. Being unable to walk four steps
after the injury is one of the more useful signals there is. It does not confirm a
fracture, but it does mean the knee needs assessing rather than resting.
The swelling came on fast. A knee that swells within an hour or two is
behaving differently from one that puffs up overnight. Rapid swelling suggests bleeding
inside the joint, which happens with fractures and with significant ligament injuries.
The knee will not move properly. Being unable to straighten or bend it,
or a sensation that it is locked or catching, is worth review.
Alongside those: bruising around the knee or upper shin, pain worse on the inside or
outside than in the middle, and any sense that the knee might give way.
Go to an Emergency Department if
- The knee is obviously deformed, or you think it may be dislocated
- There is a wound over the knee after the injury
- The foot is numb, tingling, pale or cold, or calf pain is worsening
- Swelling is increasing rapidly and pain is severe
- You have a fever or a hot, red joint, or feel unwell in yourself
That last one is worth taking seriously even without an injury. A hot, swollen joint with
a fever can indicate infection, which is an emergency.
The first 48 hours
Before you are assessed, the aim is comfort, swelling control and protection.
- Stop the activity. Pushing through a knee injury rarely ends well.
- Ice for 10 to 15 minutes at a time, several times a day, with a cloth against the
skin. - Light compression if it feels better and does not increase pain or numbness.
- Elevate the leg when resting.
- Use crutches if weight-bearing is painful or the knee feels unstable.
Paracetamol or ibuprofen suit many people, but check with a pharmacist or your GP if you
take other medications or have other conditions. Avoid deep squats, running and twisting
until the knee has been assessed.
Cannot take four steps, or the knee swelled within the
hour? That needs looking at today.
Book online or call
1300 525 666.
How the decision about imaging is made
Not every knee injury needs an X-ray, and clinicians use established guidelines
alongside their examination to decide. Those guidelines weigh your age, where exactly the
knee is tender, how far it will bend, and whether you can walk on it.
Rather than trying to apply that yourself, the practical version is this: if you cannot
weight-bear, the swelling came on quickly, the knee will not move properly, or the pain is
not settling after a few days, get it looked at. The examination determines whether imaging
is needed, and a knee that looks unremarkable can still hide a fracture.
Imaging is also more likely to be recommended after a high-energy injury such as a car
or bike accident, or if you have osteoporosis or another reason for fragile bones.
What can break around the knee
Patella fracture. Usually a direct blow, or a fall straight onto the
kneecap.
Tibial plateau fracture. The tibial plateau is the top surface of the
shin bone, forming the lower half of the knee joint. It can fracture after a fall, a direct
impact or a twist, and because the break can involve the joint surface itself, diagnosis
matters. These are among the easier fractures to miss: without an obvious deformity, people
assume they have sprained something. Swelling and difficulty weight-bearing after a twist
are the clues.
Distal femur and proximal tibia fractures. Typically higher-energy
injuries, or lower-energy ones in older adults with fragile bones.
Ligament injuries. ACL, MCL and LCL injuries cause instability, and the
swelling may be immediate or come on over a day. See our page on
ACL tears.
Meniscal tears. Often a twisting injury, and often accompanied by
catching or locking.
Several of these do not show on a plain X-ray. If the X-ray is clear but symptoms remain
concerning, a CT may be arranged for better bone detail, or an MRI to look at the ligaments
and menisci.
What assessment involves
A history of how the injury happened, then examination of swelling, movement, tenderness
and stability. X-ray if it is indicated. Then a plan: crutches or a brace, pain control,
and a follow-up point. Where a fracture is confirmed, early orthopaedic management guides
how much weight the knee can safely take and when that can progress.
Frequently asked questions
Can you walk on a tibial plateau fracture?
Some people can partially weight-bear, but walking is usually very painful. If you
cannot take four steps, arrange urgent assessment and imaging.
Does a swollen knee always mean a fracture?
No. Ligament and meniscal injuries swell too. What matters is the combination:
significant swelling, difficulty walking, or a concerning mechanism.
Which imaging is best?
X-ray is usually first. CT clarifies bony detail; MRI shows soft-tissue injury. Your
clinician chooses based on the examination.
How long should I wait before getting it checked?
If you cannot weight-bear, do not wait. Otherwise, a knee that is not clearly improving
after two or three days is worth reviewing.
Can I drive with a knee injury?
It depends which leg, whether you can brake safely under pressure, and whether you are
in a brace. Worth asking directly at your appointment rather than assuming.
Book an assessment
If you have injured your knee and are unsure whether it needs imaging, we can assess it
and arrange X-ray at the same visit.
Book online or call
1300 525 666. Clinics at
Southport on the Gold Coast and
Springwood in South Brisbane.
Related reading:
ACL tear ·
Ankle fracture or sprain ·
Tibia fractures