FAQ: Early Stages After ACL Reconstruction Surgery

Finn Diamond 13/04/26

When can I walk without crutches? There is no rush to come off crutches. Early on, your quadriceps (thigh muscle) will be weak and you may not be able to fully straighten your knee. Coming off crutches too soon can irritate the knee and slow your progress later in rehab.
You can stop using them when you can fully straighten your knee and have good quadriceps contraction and hip lock mechanics.

Will I need to wear a brace? If you’ve had an isolated ACL reconstruction, you usually won’t need a brace. However, if you’ve also had a meniscus repair, you may need to wear one early on to protect the healing tissue, depending on what the surgeon has done.

Why can’t I fully straighten my knee? This is common after surgery and is usually due to swelling, joint stiffness, and reduced quadriceps muscle activation. Regaining full knee extension is very important, so make sure you complete your exercises regularly throughout the day. Not just once a day, but three to four times plus.

Why does it hurt to bend my knee? Pain with bending is normal early on. The incision sites at the front of the knee can feel tight or sensitive when you bend. It’s still important to keep working on your range of motion exercises in this direction also multiple times a day. This is where staying on top of your pain medication can be beneficial, to help with adherence to your exercise plan and to better manage how sore the knee is.

When can I drive? You can usually return to driving when you can safely perform an emergency stop and get in and out of the car comfortably. This is typically around 4–6 weeks, but it can depend on which leg was operated on and whether you drive a manual or automatic car.

When can I return to work? This depends on your job:

• Desk-based work: around 3–4 weeks

• Physical jobs (e.g. construction, trades): may take 6–9 months

When can I go back to the gym? A lot of the early-stage ACL exercises can be completed at home as they are usually body weight strengthening, simple balancing or your range of motion and quadriceps activation exercises. This is because initially the main goals are regaining full knee extension, improving knee bending (flexion), activating your quadriceps, and reducing swelling. Typically, these outcome measures take around 4-6 weeks to be met. Your physiotherapist or osteopath once you have met these goals will help guide you through certain exercises and movements in the gym you can complete.

Important things to watch for (Red Flags):

• Signs of infection: fever, chills, increasing redness or swelling

• Possible blood clot (DVT): Worsening calf or knee pain, redness, feeling unwell

• Nerve issues: weakness in the foot and/or changes in sensation down the leg

• Knee locking: the knee gets stuck and cannot move

If you notice any of these, contact your physiotherapist or surgeon immediately.

Helpful tips in the early stages:

Nutrition: Eat enough to support recovery. Focus on protein for muscle repair and fibre to help with digestion (especially if taking pain medication). Even if your appetite is low, which can be normal after surgery, your body needs fuel to heal!

Sleep: Aim for plenty of sleep (ideally 8–10 hours), as this is when your body does most of its recovery. This is not the time for late nights watching shows or playing video games.

Desensitise the knee: Gently touching or massaging around the knee can help reduce sensitivity. As the scar heals, direct massage over the incision sites can help with breaking down the scar tissue and desensitising the area. It can also help with improving any numbness that has lingered since surgery. Touch the knee and become familiar with it again, it is a part of your body so don’t treat it as a stranger.

Track your swelling: Measure your knee daily to monitor swelling. Increased swelling can mean you’ve done too much and need to rest or reduce your activity. This will be more helpful once you have progressed off the crutches and you are completing more gym based exercises. However, it is a good habit to get into and can be a useful tool to track knee irritation even if there is no pain.

Track your steps: Keeping an eye on your step count can help you gradually build activity without overloading the knee and can allow you to track swelling more specifically.

Final note: Recovery from ACL surgery takes time. It’s a long-term process with ups and downs, so having a practitioner you trust and a good support network is key. This is a marathon not a sprint. Stay consistent, be patient, and you’ll get back to doing what you enjoy.