You’re running down the field and suddenly change direction to avoid an opponent. Your knee twists. You feel a pop. Could it be your ACL (anterior cruciate ligament)?
ACL injuries are fairly common knee injuries, according to the American Academy of Orthopaedic Surgeons. They’re especially common among athletes who play fast-paced or aggressive sports. In games like football, basketball, soccer, lacrosse, tennis, and even flying disc sports like Ultimate, you have to stop, change directions, and pivot quickly.
The good news is that many people can regain full knee function after an ACL injury. Sometimes these injuries are avoidable.
How ACL Injuries Happen
The ACL is one of the four ligaments that hold the bones of the knee together. It plays an important role, helping connect the thigh bone (femur) to the shin bone (tibia). The ACL runs through the middle of the knee to provide stability. When you hurt your ACL, your knee can’t work properly.
ACL tears and sprains often happen after jumping, sprinting, or taking a hit. They can also happen if you lose your footing or slip while mowing the lawn or walking on an uneven surface.
The pop you feel when your knee twists or pivots — as well as pain and instability — is what most people associate with ACL injuries.
You may also notice:
- Your knee “giving out” like it can’t support you
- Reduced range of motion, so that you can’t straighten or bend your knee fully
- Pain when walking or standing
- Swelling or a “crunchy” feeling
If you suspect you’ve injured your ACL, don’t walk! Seek help immediately. Getting treatment within an hour can help prevent further injury.
The experts at UPMC Sports Medicine can evaluate your injury. You may also need an MRI to confirm the severity of an ACL tear or sprain. Not every knee injury is an ACL injury.
What to Expect After an ACL Injury
Your symptoms and treatment will depend on the severity of your ACL injury.
Minor ACL injuries
A minor (partial) tear or sprain often can heal without surgery. Your doctor might suggest that you:
- Ice your knee several times a day
- Keep weight off your knee, and keep it elevated
- Use crutches and protective braces
- Rest or reduce your activities for at least several weeks
- Do physical therapy to strengthen the muscles around your knee
- Plan on recovery taking three months or longer
Full ACL tears
A full tear of your ACL won’t heal by itself. In addition to ice, rest, and elevation, surgery is usually the best option if you want to play sports again.
An ACL injury used to mean hanging up your cleats for good. Now surgeons say you can expect to resume most activities after about nine months of rehabilitation.
ACL surgery involves replacing the torn ligament with a new one. The surgeon takes tissue from another part of your knee to make a new ACL.
The doctors at UPMC have pioneered new types of ACL surgery. Together with a team of orthopaedic surgeons, sports medicine doctors, physical therapists, athletic trainers, performance coaches, sports psychologists, and nutritionists, they create individual, research-driven treatment plans.
ACL Rehab After Surgery
After surgery, your ACL rehab will happen in three phases:
- For the first four weeks, rest and reduce the inflammation as your knee heals
- For the next few months, work on regaining range of motion and strength
- After about three months, focus on functional fitness. This may include jogging, agility training, single-leg exercises, and pivoting movements
Be patient. That nine-month estimate helps prevent you from developing osteoarthritis or reinjuring your knee.
How to Prevent ACL Injuries
Accidents happen. You can slip on a wet lawn or get tackled on the soccer field without warning. But many ACL injuries are preventable. This is especially true when they’re caused by weakness or imbalance.
You can reduce some risks by strengthening the muscles that surround and protect your knees. UPMC Sports Medicine offers an ACL Injury Prevention Program designed to help athletes. This 9-week program builds strength and identifies muscular imbalances while improving athletic performance.
Sources
American Academy of Orthopaedic Surgeons (AAOS), OrthoInfo. Anterior Cruciate Ligament (ACL) Injuries.
Applied Bionics and Biomechanics. A Review on Biomechanics of Anterior Cruciate Ligament and Materials for Reconstruction.
Primary Care: Clinics in Office Practice. Common Medical Concerns of the Female Athlete.