ACL tear: do you always need surgery?

No. Many people with a torn anterior cruciate ligament (ACL) do well with physiotherapy alone. Surgery is usually advised when the knee keeps giving way, when you want to return to sports that involve twisting and sudden stops, or when other parts of the knee are damaged too.

What the ACL does

The ACL is a strong band of tissue in the middle of the knee. It stops the shin bone from sliding forward under the thigh bone and keeps the knee steady when you turn. Tearing it is one of the most common knee injuries in sport.

Most ACL tears happen without anyone touching you. A sudden change of direction, a quick stop, or a bad landing from a jump puts more force through the ligament than it can bear. Football, basketball, volleyball and padel all involve these movements.

How a torn ACL feels

People often describe a pop, then the knee giving way. Other signs are:

• swelling that builds up within a few hours, usually by the next day
• pain, and difficulty walking normally
• loss of full bending or straightening
• a feeling that the knee is loose or unreliable

The pain and swelling often settle over a few weeks. That can be misleading. Going back to sport on a knee that still feels unstable risks more damage inside the joint.

How doctors confirm it

The doctor asks exactly how the injury happened, then examines both knees and compares them. Special tests check how far the shin bone moves forward. An X-ray looks for a broken bone. An MRI scan shows the ligament and also the meniscus, cartilage and other ligaments, which matters for the decision.

About half of ACL injuries come with another injury, such as a meniscus tear or cartilage damage.

When surgery is often not needed

The AAOS says choosing not to operate is reasonable for some people. Non-surgical care is more likely to work if:

• the tear is partial and the knee feels stable
• the tear is complete, but the knee does not give way in daily life and you do not play twisting sports
• your work is light, or your lifestyle is not very active

Treatment then means a structured physiotherapy programme to rebuild the thigh and hamstring muscles, balance and confidence in the knee. A brace may help for some activities. Recovery from a partial tear usually takes at least 3 months.

The AAOS suggests that for a fresh ACL tear on its own, about 12 weeks of non-surgical treatment is a sensible first step. If surgery then looks right, doing it within about 5 months lowers the risk of further meniscus and cartilage damage.

When surgery is usually advised

Surgery is more often advised for:

• people who play sports with pivoting, cutting or jumping, and want to go back to them
• people whose jobs involve heavy manual work or turning on a loaded leg
• a knee that keeps giving way despite good physiotherapy
• combined injuries, such as an ACL tear with a meniscus tear that can be repaired

This last point matters. A knee that keeps giving way can tear the meniscus and wear the cartilage over the following years. A meniscus repair is also more likely to heal if it is done at the same time as the ACL reconstruction.

Age on its own does not rule surgery in or out. The AAOS says activity level, not age, should guide the choice. Children and teenagers need special care because of their growth plates, and techniques that avoid the growth plate are used.

What ACL surgery involves

A torn ACL is usually reconstructed rather than stitched, because the ligament heals poorly inside the joint. The surgeon replaces it with a graft, most often a piece of tendon from your own leg, such as a hamstring tendon. The operation is done by keyhole surgery (arthroscopy).

Rehabilitation starts straight away. The first goals are to straighten the knee fully, control swelling and wake up the thigh muscle. Most people return to full sport within 6 to 12 months, once strength, balance and control are fully back.

Questions to ask at your visit

• Is my tear partial or complete?
• Is anything else in the knee damaged?
• What can I expect if I try physiotherapy first?
• What would I need to do to return to my sport?

When to see a doctor

See a doctor soon if your knee swelled up quickly after a twist, if it gives way, or if you cannot fully straighten it. A knee that locks, or a knee you cannot put weight on, needs to be seen the same day.

Read more about ACL surgery in Dubai, sports injuries and meniscus tears. For a serious injury with a deformed leg or heavy bleeding, call 998 for an ambulance.