The guide
Read up between sessions.
Short, sourced pieces from the ACL Recovery Team on what each week should feel like and what to do about it. New articles are added regularly; subscribe with RSS.
Daily life · Early recovery
Flying after ACL surgery: timing and clot risk
No guideline we found sets a date for flying after ACL surgery. Surgery and long flights both raise clot risk, most of all a long flight in the first weeks.
Progression · Daily life
Rest days in ACL rehab: why they are part of the plan
Rest days are part of ACL rehab: muscles gain from recovery, and Delaware's running plan never runs two days in a row. Walking and icing usually carry on.
Early recovery · Timeline
Meniscus repair with ACL reconstruction: what changes
A stitched meniscus usually means weeks of limited weight and bending on top of the ACL protocol. How long varies by repair and surgeon.
Mindset · Daily life
Staying motivated through nine months of ACL rehab
Motivation in ACL rehab tends to sag in the long middle months. What the studies found gets in the way, and what helps: support, small goals, a record.
Timeline · Return to sport
Why do ACL guidelines say nine months?
Nine months comes from two cohort studies of reinjury, not from a graft that heals on a set date. It is a floor for pivoting sport, not proof of readiness.
Return to sport · Progression
Return to sport after ACL reconstruction
Most people return to some sport after ACL reconstruction, about half to competition. Clearance rests on tests, not the date, and the return is staged.
Return to sport · Progression
Second ACL injury: how common and what lowers the risk
About 1 in 7 people tear an ACL again, in the graft or the other knee. The risk is highest in under-25s who return to sport. What lowers it.
Mindset · Return to sport
Fear of reinjury after ACL surgery: how common, what helps
Fear of reinjury is the commonest reason people never go back to sport after ACL reconstruction. What the ACL-RSI scale measures, how scores change, what helps.
Daily life · Early recovery
When can you have sex after ACL surgery?
Usually once the wound has closed and the swelling settles, in positions that keep the knee straight and unloaded. No ACL study gives a date; the surgeon does.
Measuring progress · Return to sport
Hop tests after ACL surgery
The four single-leg hop tests used after ACL reconstruction, how the limb symmetry index is worked out, and what a symmetrical hop distance can hide.
Measuring progress · Strength
Limb symmetry index after ACL surgery
What the limb symmetry index measures, where the 90 per cent threshold came from, and why a good score can flatter a recovering knee.
Mobility · Measuring progress
How to measure knee extension at home
Why zero degrees is the wrong target, the two ways extension is measured, and how much of a day-to-day change is real rather than noise.
Strength · Early recovery
Electrical stimulation for the quad after ACL surgery
What NMES is, what the trials and the Aspetar guideline found it does for quadriceps strength after ACL reconstruction, and when it is used.
Strength · Exercises
Blood flow restriction training after ACL surgery
What blood flow restriction training is, what the trials after ACL reconstruction found, where guidelines place it, and why the cuff pressure is measured.
Pain and swelling · Early recovery
Ice, elevation and compression after ACL surgery
What the trials found when ice, cold devices and compression were tested after ACL reconstruction, and how the three are usually applied at home.
Pain and swelling · Early recovery
Blood clots after knee surgery
How common blood clots are after ACL reconstruction, when the risk is highest, the signs of a DVT or a pulmonary embolism, and when to get help.
Progression · Daily life
How much physiotherapy do you need after ACL surgery?
What the trials say about supervised appointments versus a home programme after ACL reconstruction, how many sessions people get, and what matters more.
Pain and swelling · Mindset
Normal soreness or a setback in ACL rehab?
How to tell ordinary soreness after a rehab session from a knee reacting badly, what swelling adds, and which signs get reported the same day.
Mobility · Pain and swelling
Cyclops lesion after ACL surgery
What a cyclops lesion is, why a nodule of scar tissue can stop the knee straightening, how often it causes symptoms, and what is usually done about it.
Timeline · Early recovery
Quadriceps tendon graft recovery after ACL surgery
Where a quadriceps tendon graft is taken from, why extension gets watched so closely afterwards, and what the strength and registry data actually show.
Timeline · Early recovery
Hamstring vs patellar tendon graft: the early weeks
What differs in the first weeks after a hamstring or a patellar tendon graft, what each donor site adds, and how much of rehabilitation is the same.
Daily life · Pain and swelling
When can you kneel after ACL surgery, and why it hurts
Safe for the new ligament once the wound has healed and the knee bends. What hurts is the skin, scar and tendon in front, worst after a patellar tendon graft.
Daily life · Exercises
When can you swim after ACL surgery?
Not until the wound has fully healed and your surgeon agrees. Pool walking and front crawl usually come back first; the breaststroke kick is the last to return.
Exercises · Mobility
When can you cycle after ACL surgery? Indoor bike to road
The stationary bike comes early, once the knee bends enough for the pedals to go round; a higher saddle brings that forward. Riding outdoors comes later.
Early recovery · Pain and swelling
Numbness beside the scar after ACL surgery
Why a patch of skin below the kneecap stops feeling after ACL reconstruction, how common it is by graft and incision, and how long it usually lasts.
Using the app · Measuring progress
How to choose an ACL rehab app
What to look for before you commit: criteria-based progression, range-of-motion and pain logging, a programme your physio can change, and where your data goes.
Daily life · Early recovery
Stairs after ACL surgery: the technique and the timeline
Up with the good leg, down with the operated one. Step-over-step returns when the knee bends and holds under load; coming down is the last to feel normal.
Early recovery · Daily life
Do you need a brace after ACL reconstruction?
What post-operative and functional braces do, what the randomised trials found when the brace was taken away, and why two surgeons give different instructions.
Early recovery · Daily life
How long do you need crutches after ACL surgery?
Usually about two to three weeks after an uncomplicated ACL reconstruction, longer if something else was repaired. How you walk decides it, not the date.
Daily life · Timeline
Going back to work after ACL surgery
What the research found about timing, why a desk job and a knee-demanding job are different questions, and what usually decides the date.
Daily life · Timeline
When can you drive after ACL reconstruction?
Why the answer ranges from two weeks to six, what the braking studies measured, and how the side, the graft and the painkillers change it.
Early recovery · Strength
Quad activation after ACL surgery
Why the thigh muscle refuses to fire in the first weeks, what arthrogenic muscle inhibition is, and what quad sets and electrical stimulation do about it.
Mobility · Early recovery
Why won't my knee straighten after ACL surgery?
Swelling, guarding and a quiet quadriceps hold the knee bent. Most straighten with heel props and quad work; a block that stays is checked for scar tissue.
Pain and swelling · Early recovery
How to reduce swelling after ACL surgery
Why the knee fills with fluid, what ice, elevation and compression actually did in the trials, and how swelling is measured and used to pace rehabilitation.
Early recovery · Daily life
How to sleep after ACL surgery: positions and side sleeping
Back first, heel propped and leg raised; on your side with a pillow between the knees once your surgeon allows the bend. The brace at night is their call.
Early recovery · Timeline
What is normal in the first week after ACL surgery
Swelling, a numb patch, a thigh that will not fire: what the first seven days usually look like, what to work on, and the few things that are not normal.
Timeline · Progression
How long does ACL surgery recovery take?
Six months, nine months, a year: where those numbers come from, what happens in each phase, and why the end of ACL rehab is not really a date.
Mobility · Measuring progress
How to measure knee flexion at home with your phone
What flexion and extension mean, why a phone's sensors are good enough to track them between physio visits, and how to take a reading you can trust.
Return to running · Progression
When can you run again after ACL reconstruction?
Most people are told "about three months", but the calendar is the weakest test. The strength, range and control criteria physios use before the first jog.