Phase 0: Getting Ready for ACL Surgery (Prehab)

The weeks between your ACL diagnosis and your surgery date are not a waiting room — they're your first phase of rehab. We call this Prehab. The goal is simple: walk into surgery as strong, healthy, and well-prepared as possible, so you walk out of it into a faster, smoother recovery.

Here's what that means in practice.

1. Protect Your Knee — No Pivoting Sports

Your ACL is one of your knee's main static stabilizers. With it injured, your knee is more vulnerable to further damage — particularly to the meniscus, which may or may not already be torn alongside your ACL.

Between now and surgery day, avoid any pivoting, cutting, or contact sports — football, basketball, badminton, netball, and similar activities are off the table. A further injury now doesn't just set you back; it can mean more repair work needed during surgery itself, which we want to avoid.

2. Stay Well

Surgery requires you to be in good health. If you develop flu-like symptoms in the lead-up to your operation, we may need to postpone the surgery — both for the safety of anesthesia and to reduce the risk of infection at the surgical site.

Take sensible precautions in the weeks before surgery: get enough rest, avoid unnecessary exposure to illness, and let us know early if you're feeling unwell.

3. Keep Your Skin Intact

We need clear, unbroken skin around your knee and legs on the day of surgery. If you notice any rashes, resist the urge to scratch — instead:

• Take antihistamines if needed
• Apply moisturizer regularly to keep skin supple
• Avoid activities that risk cuts, scrapes, or open wounds on your limbs

Any break in the skin near the surgical site raises infection risk and may delay your operation.

4. If You Smoke, Now Is the Time to Quit

Smoking works against you in two ways:

• It increases your risk of post-surgical infection
• It reduces blood supply to the tissues that need to heal — fewer capillaries means less oxygen and fewer nutrients reaching your knee when it matters most

Recovery depends on healthy blood flow to the surgical site. Continuing to smoke through this period is, in a real sense, working against your own recovery. If you've been thinking about quitting, this is as good a reason as any to start now.

5. Build Your Baseline Strength

This is the part you can control — and it matters more than most patients realize.

Our bodies are remarkably resilient and capable of healing, but that capacity is something we can actively support, not just wait on. The stronger and more stable your knee is going into surgery, the better position you're in to begin rehab afterward and get back to walking — and eventually sport — sooner. Time between diagnosis and surgery is not time lost; it's time to invest.

Focus your energy on:

• The strengthening exercises prescribed by your physiotherapist
• Regular use of neuromuscular electrical stimulation (NMES) to maintain muscle activation and reduce quadriceps weakness before surgery

(See our NMES guide for more on how and why this helps.)

6. Pre-Surgery Housekeeping

A few practical steps before your surgery date:

• Pre-op washes and nasal cream — use these exactly as prescribed by the pharmacist. They help eradicate bacteria on your skin and in your nasal passages before surgery, lowering infection risk.
• Scans done outside NUH? If your MRI or X-rays were done in a private setting, they'll need to be uploaded to the hospital system (a nominal fee applies). Please do this ahead of time — if you haven't yet, let our team know +65 6772 2100 or and email your request to ortho_enquiries@nuhs.edu.sg.
• On the day of surgery, bring your physical reports and scans with you regardless, as a backup.
• Reporting time — our operating theatre team will call you to confirm what time to report. As a general rule, start fasting from midnight the night before, even if your surgery is scheduled for the afternoon. This keeps you eligible to be moved earlier in the day's list if an earlier slot opens up due to a cancellation. You'll need to be fasted for 6–8 hours before general anaesthesia.
• Financial counselling — if this hasn't been done yet, our team will call you beforehand to go through it. If you've already had your financial counselling, you're welcome to call the same number for any further questions.
• Pre-op assessment with the anaesthetist — patients above 50 years old, or with other medical conditions, may need an additional appointment with the anaesthetist before surgery. This is routine — just follow our instructions and raise any questions you have at that visit.
• Functional assessment — ideally completed with our clinical exercise physiologists before surgery. If you haven't managed to do this beforehand, don't worry — the same questionnaire can be completed shortly after your surgery instead.

Any Questions?

I'll see you before your surgery to walk through any final questions in person. If anything comes up before then, feel free to reach to me — I am happy to help however I can.

Ready to understand what comes after surgery? Visit the ACL Recovery Hub for the full picture of your rehab journey.