Recovering from ACL reconstruction takes time and commitment. Most people who need this surgery have experienced a knee injury that caused a popping sensation, significant swelling, and pain that gradually settled over several weeks.
The main aim of surgery is to restore knee stability and prevent the knee from giving way during everyday activities and sport. Surgery is usually performed once the initial swelling has settled and normal knee movement has returned.
Although surgery stabilises the knee, it also causes temporary pain and swelling. It is important to understand that recovery is gradual, and most patients require 9–12 months before returning to contact sports or activities involving pivoting, cutting or sudden changes in direction.
The reconstructed ACL needs time to heal and become incorporated into the knee. During this time, the muscles around the knee—particularly the quadriceps, hamstrings, glutes and core—play an essential role in protecting the knee and must be strengthened throughout rehabilitation.
Before Surgery
Preparing well before surgery can make recovery smoother.
Before your operation you should aim to:
Reduce swelling.
Regain full knee movement, especially being able to fully straighten the knee.
Improve thigh muscle strength.
Establish care with a physiotherapist who will guide your rehabilitation.
Having surgery before knee movement has fully returned increases the risk of postoperative stiffness.
Until surgery, avoid activities that involve twisting, pivoting or rapid changes of direction. Swimming, cycling and strength training are excellent ways to maintain fitness.
After Surgery
Phase 1: Weeks 0–2
Goals
Control pain and swelling.
Walk safely.
Regain full knee extension (straightening).
Re-establish quadriceps muscle activation.
Most patients go home on the day of surgery using crutches. Unless instructed otherwise, you can put weight through the operated leg, although walking should be kept to a minimum during the first few weeks.
The bulky bandage can usually be removed the day after surgery. Leave the waterproof adhesive dressings in place until your two-week wound review.
To reduce pain and swelling:
Ice the knee regularly.
Elevate the leg when resting.
Pump your ankle frequently to improve circulation and reduce the risk of blood clots.
Regaining Knee Movement
Restoring full knee extension is one of the most important early goals.
Practice:
Lying on your back and gently pressing the back of your knee into the bed.
Placing a pillow under your calf or ankle—not under your knee—to encourage the knee to straighten.
Hold for 30 seconds, repeat 3 times, 3 times per day.
Your physiotherapist will also begin gentle exercises such as straight leg raises and quadriceps activation exercises.
Phase 2: Weeks 2–12
Goals
Walk normally.
Restore full knee movement.
Rebuild strength.
Continue icing the knee as needed.
Begin using an exercise bike as soon as comfortable, using low resistance and raising the seat if necessary.
Your physiotherapist will prescribe an exercise program to complete three times per day, focusing on:
Knee bending and straightening.
Quadriceps and hamstring strength.
Balance and movement control.
Exercises commonly include:
Heel slides
Straight leg raises
Wall squats
Lunges
Gym-based strength training is encouraged as symptoms allow. Your physiotherapist will modify exercises depending on the type of graft used. For example, hamstring strengthening may initially be limited if a hamstring tendon graft was used.
During the first two months, resisted open-chain quadriceps exercises (where the foot is not in contact with the ground) are generally avoided to protect the healing graft.
Phase 3: Months 3–6
Goals
Restore strength.
Improve balance and knee control.
Begin returning to impact activities.
The aim is to regain at least 80% of the strength of the uninjured leg.
Many patients begin jogging during this phase, although the exact timing varies.
Your rehabilitation will progress to:
Jumping and landing drills
Hopping exercises
Balance and proprioception training
These exercises teach the muscles around the knee to better protect the reconstructed ACL during sport and daily activities.
Phase 4: Months 6–12
Goals
Sport-specific rehabilitation.
Safe return to sport.
Exercises
As your strength and control improve, your physiotherapist will gradually introduce:
Running
Pivoting
Cutting
Changes of direction
The rehabilitation program should be tailored to your individual sporting goals.
Many patients require the full 12 months before returning to unrestricted sport.
Return-to-Sport Checklist
Before returning to full sport, you should have:
No knee swelling.
Full knee movement.
Normal walking and running without a limp.
The ability to squat without assistance.
Comfortable figure-of-eight running.
Single-leg hop and jump tests that are at least 90% of your uninjured leg.
Long-Term Outlook
Approximately 85–90% of patients achieve a stable knee following ACL reconstruction. However, around 65% return to their previous level of sport.
The best outcomes come from following a structured rehabilitation program, progressing gradually, and working closely with your physiotherapist. Recovery takes patience, but consistent rehabilitation gives you the best chance of returning safely to the activities you enjoy.