An ACL tear is a serious injury to the knee and should not be taken lightly. This page includes information about the knee and the Anterior Cruciate Ligament injuries, as well as what to expect throughout the rehabilitation process. For more information on sports-related injuries, take a look at our sports medicine physical therapy page.

 

 

The Anterior Cruciate Ligament (ACL) is considered the most important of four major ligaments located in the knee, providing about 90% of its stability. It attaches at the front of the femur (thigh bone) and back of the tibia (main shin bone), to prevent forward motion of the lower leg as well as provide stability during twisting and planting activities. The most frequent complaint of an injured patient is instability of the knee and occasionally “giving out.” Although the ACL is often injured among athletes it is not uncommon in the non-athletic population. ACL tears are more common amongst women, a problem that has been attributed to numerous factors including: a slightly different angle that the femur with the hip bone, joint laxity, and hamstring-quadriceps strength imbalances.

 

Knee movements that place great amounts of strain on the ligament can cause an ACL injury. There are many ways that an ACL injury can occur. The most common mechanism is pivoting on the knee with the foot planted.  Common ways that this can occur in athletics is planting and twisting, and pivoting while slowing down from a sprint. The second mechanism that often causes damage to the ACL is knee hyperextension, where the knee is pushed farther than it can go in a normal straightening position ie. landing from a jump with a straightened leg, like in basketball.  The final mechanism of injury is wear and tear, where small little tears have accumulated over time and one small stress causes a complete tear. It is not uncommon to hear a pop when an ACL injury takes place, but the absence of a pop does not rule out a tear. It is also quite common to see concurrent injuries to other ligaments most commonly the medial collateral ligament (MCL) and the medial meniscus.

After any injury it is best to first consult with your primary physician. Typically the doctor will first ask about the patients’ past medical history concerning knee injuries. Then they will ask some more questions about the injury and events leading up to it and will then perform several knee stability tests, where they will be able to tell if there is damage to the ligament. Based on the doctor’s findings they may order an X-Ray, MRI, or a KT1000. These images and tests will provide further information about the extent of the injury. When an ACL is only partially torn, a decision must be made on whether or not to undergo surgery to repair the injury. There is no guideline for when exactly an injury must be surgically repaired because each person’s needs are different. Therefore the decision must be made based on how unstability the ACL injury is and how that is going to affect the patient’s functional goals. If the patient feels there is instability in the knee all of the time or even some of the time, and they have positive findings on instability test (Lachman test and pivot shift are the standard), then surgery is likely a good option. The ligament can not simply be sutured back to the bone; instead it is necessary to completely replace the injured ligament from another area of the body or someone else’s body. Surgery can be a large commitment and a temporary lifestyle change while recovering. However, the staff at Westwood Physical Therapy specializes in maximizing your recovery and gearing your progression toward returning to normal every day life.

 

A very similar approach to rehabilitation is used whether the injury was repaired surgically or not. The first goal before beginning manual therapy and strengthening exercises is to let the surgical wounds heal. After this stage the physical therapist begins working with the patient on reducing swelling, regaining range of motion (ROM), strengthening, and regaining neuromuscular control of the muscles that support the knee joint. The final goal is functional movements that can be applied to the patient’s everyday needs.

 

Before even seeing a physical therapist it is important to apply the P.R.I.C.E. procedures to reduce swelling and pain, as well as maintain range of motion. P.R.I.C.E. stands for Protection, Rest, Ice, Compression, and Elevation. The initial therapy appointment, about one to two weeks post-surgery, will continue to build on this concept. The therapist will first ask a series of questions and then visually and physically examine the injury. Once an initial assessment is made, the physical therapist will develop a detailed plan of rehabilitation. This plan will likely include a number of phases that are typically seen in rehabilitating an ACL injury:

 

Early Rehabilitation Phase: The main goals of this phase are to reduce pain and swelling, while steadily increasing range of motion and promoting muscle activity. The therapist will take the knee through different passive range of motion sequences. Early strengthening activities such as quad sets will begin the strengthening process. Different manual therapy techniques will also help achieve the goals of this phase.

 

Second Rehabilitation Phase: About 3 to 4 weeks after surgery or injury, most of the pain has disappeared and now it is necessary to protect the knee against over activity. Range of motion is a key concern in this phase. Patients begin to do exercises in the pool or on a stationary bike and some patients will even start to do mini squats against the wall. Some balance activities will be introduced, as well as small stair step-ups and leg press machines within a given range of motion.

 

Controlled Ambulation Phase: Four to six weeks after surgery the main goal is to bend the knee to130 degrees. New exercises will be introduced in addition to continuing to improve on any previous exercises. Squats will be done with a single leg. Step ups will be on a larger step. Calf strengthening and stretching will also be added. Resistance and range on the bike should also increase. A home exercise program will be emphasized at this time and will help the patient continue to improve their range of motion and gain strength in their leg muscles. Your physical therapist will make a printed handout of all of your exercises and their respective frequency in order to remind you of correct form and technique.

 

Protection Phase: By the six to eight week point, full range of motion should be achieved. Exercise, both in the clinic and at home, will continue to progress. Weight will be added to some exercises in the clinic, where the therapist can closely monitor your progress.

 

Light Activity Phase: During this phase the emphasis is on balance and movement. Additional strengthening exercises are also important. This gives the knee greater stability which will translate well to functional activities of daily life. Examples of exercises done during the light activity phase include: lunges, squats on a BOSU, quick step touching, step downs, and different stepping patterns while attached to a sport cord.

 

Functional Activity Phase: This final phase usually begins at ten weeks after an operation. It will continue until all of the patient’s goals are met and they are able to go through functional activities that will be encountered in their daily life. Jogging on a treadmill in a controlled environment is common, as well as introducing agility drills. Grid touching, box jumping, balancing and tossing a ball, and hopping are all regular exercises used to achieve the patient’s goals. Activities that specifically apply to the patient’s fitness goals will also be emphasized at this time. Finally, if necessary this is a good time for a patient to be fitted for a sport brace.

 

Rehabilitation from an ACL injury varies based on the severity of the injury; each person’s recovery time is different. Factors such as: age, extent of injury, success and type of surgery, work ethic during rehab and overall health and fitness of the patient can drastically effect how long an ACL injury recovery can take. Rehab following the traditional ACL repair surgery often takes six to nine months until full strength and function are restored. Light jogging and running in a straight line is sometimes seen at about 4 months after surgery. The rule of thumb to return to more aggressive activities is when the recovering knee is at least 90% of the strength of the opposite leg. Some doctors are now performing an accelerated surgery that can put the athlete back on the playing field in six months. It is necessary to consult with your physician before exploring this option.