Knee > ACL Tear > Treatments

    Physical Therapy

Home Recovery

If you and your doctor decide on a non-surgical treatment to repair your torn ACL (anterior cruciate ligament), you will most likely need to do exercises to strengthen the muscles around the knee. You will need strong hamstring muscles in the back of your thigh and quadriceps muscles in the front of your thigh to stabilize your knee so it can support your weight. Doctors often prescribe physical therapy instead of surgery for less active people or if an ACL tear is not complete. You will probably be given a regimen of exercises that begin at home and continue for up to six months after the injury. You will likely feel pain and discomfort for the first few days after the injury, and your doctor may prescribe medications depending on the severity of the pain. These will likely be mild, over-the-counter painkillers such as ibuprofen or acetaminophen. Elevate your knee when you are not moving around, and ice it for between 20 and 30 minutes two to three times a day to reduce pain and swelling. Physicians occasionally prescribe a CPM (continuous passive motion) machine for the non-operative treatment of an ACL tear. A CPM, which attaches to your bed and will move your leg in a continuous range of motion when turned on, will help flex and extend the knee and prevent the joint from becoming stiff due to inactivity. Within a week after the injury, many people are able to lift their leg without assistance while lying on their back. You will probably be encouraged to begin walking and putting some weight on your knee immediately with the aid of crutches and possibly a brace; your doctor will let you know what is best. You may need to use crutches for between two days and three weeks. Within two weeks, the majority of patients should be able to walk carefully without crutches. It is important to avoid activities that put your knee at risk. Anything in which you might twist your knee can lead to further injury. With proper physical therapy, people who lead more sedentary lives can often return to work within a week, and after four or six weeks most can resume driving.

Rehabilitation [top]

Your physician may prescribe visits to a physical therapist to begin supervised strengthening exercises as soon as possible after your orthopedic evaluation. Non-operative recovery from a torn ACL takes an average of between four and six months with 45-minute exercise sessions three days a week. Though everyone's rehab program is slightly different, physical therapy for a torn ACL follows a general pattern. The first three weeks are usually spent restoring a full range of motion to your knee and recovering to the point of being able to walk without crutches. Movement may initially be painful, but it is important to not allow your knee to stiffen. Rehab progresses to resistive exercises to strengthen muscles around the knee. During this time, you should be able to resume functional activities like stair climbing, single leg support, swimming, and driving. After about three months, the emphasis will change from strengthening to functional training, as you begin exercises ­ specifically geared for your activities and lifestyle ­ to regain balance and control over your body. These may include more vigorous warmups on a stationary bike, elliptical trainer, or treadmill. You should be able to return to normal activities after about four months. Physicians usually suggest that you continue strength training even after your knee has been rehabilitated. After your physician measures knee strength, you may be able to exercise at full strength and compete in your favorite activities. However, your ability to exercise may remain limited to walking and light activity even after rehabilitation. If your knee continues to buckle and remains unstable after rehab, non-operative treatment of your ACL tear may not have been effective. Instability may put your knee at risk for progressive arthritis. You should consult your physician about undergoing a more aggressive approach.


   Knee strengthening exercises: Ligament injuries

Prevention [top]

Strengthening the hamstrings and quadriceps muscles is the only proven way to prevent further ACL injury. Strengthening may help prevent instability, which can lead to injuries to knee structures, such as cartilage, meniscus, and ligaments. The more aggressive and dedicated you are during rehabilitation, the greater the chance that you will maintain a stable knee. Many of the exercises and activities that are popular for fitness put stress on your knees. To prevent further instability injuries it is important to be diligent in doing the exercises you learned from your physical therapist during rehabilitation. A small amount of pain is normal during physical activity, but if you feel so much pain in your knee to warrant taking a painkiller before an activity, you should consider cutting back or stopping. Do not play through the pain after an ACL injury - it may be a sign that your activity is putting too much stress on your knee. Here are additional ways to spare your knee of unnecessary stress:

   Daily living - the average person takes between 12,000 and 15,000 steps a day, exerting a force between two and five times your body weight on your knees. After a knee injury, take it easy on your knees during the day whenever possible to save them for activities and exercise. Avoid stairs when there is an elevator, take the shortest path when walking, and consider wearing athletic shoes designed to absorb shock.

   Muscle strengthening/conditioning - activities themselves are not a substitute for conditioning. It is essential to adhere to the muscle-strengthening program you learned in rehab throughout the remainder of your life. The best strengthening programs are low-impact and non-weight-bearing, like stationary bikes and certain weightlifting programs, so that the knees do not have to absorb shock.

   Recreation - your sport or activity of choice helps maintain mental and physical well-being, but it is not a conditioning program. Sports that require twisting and quick direction changes put great strain on your knee.


Some people feel safe wearing a knee brace after an ACL injury, but if the brace is too tight, it can cause added pain afterward an activity. If you do wear a brace, wear one that has a kneecap hole or padding. There is no evidence that braces prevent injuries, meaning they are not a substitute for increasing your muscle strength. Always consult your physician before buying a knee brace.

Physical Therapy
   Home Recovery
Reconstruction: Bone-Patellar Tendon-Bone Autograft or Allograft
Reconstruction: Quadrupled Hamstring Autograft or Allograft
Reconstruction: Quadriceps Tendon Autograft or Allograft

Copyright 2007 | Insall Scott Kelly® Institute. All Rights Reserved.