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ACL TEARS From Injury to Beyond Surgery

By Dr Mimi Zimwalt, MD

Anterior cruciate ligament (ACL) injuries occur 2-8 times more in females than males, especially in sports involving pivoting and/or jumping, such as soccer and basketball. Different theories exist as to why female athletes are at increased risk for this type of knee trauma, including body habitus and landing/stopping suddenly, especially in the wrong position on one leg. Once the ACL is torn, it takes anywhere from a few to several months before an athlete is able to engage in any type of sporting activity again, whether one undergoes surgery or not.


The ACL is one of four main static structures stabilizing the joint. It lies in the middle of the knee and functions to keep the tibia (leg bone), from slipping forward under the femur (thigh bone), when an athlete is decelerating from running/sprinting, or going down a hill or descending steps; also upon twisting or moving side to side. After rupture of the ACL, more load is imparted onto other soft tissue restraints, causing increased risk of damage to the meniscus (cartilage cushion between the femur/tibia), or cartilage cap surrounding the ends of these two bones, predisposing to early knee arthritis.


Initially after an #ACL #tear, it’s very important to protect the knee from further harm, minimize swelling/inflammation, and maximize range of motion (ROM)/muscle strength. One needs to seek out a sports/orthopaedic surgeon to guide in appropriate treatment. Bracing and physical therapy will be prescribed, the former to help with knee stability and the latter to keep the limb from becoming more weak/stiff. This rehabilitation (rehab) program is continued for about 6-8 weeks, to aid in return of function for activities of daily living (ADL’s). Beware of wearing the brace too much, however, since this will cause more muscle atrophy/deconditioning. Once ROM & muscle strength have returned, a decision needs to be made about surgical reconstruction.


Whether to continue conservative management of proceed with operative treatment, is dependent on a few variables. One needs to look at activity level, such as recreational endeavors, vocational physical requirements, and competitive athletics. Age is also an important factor to consider. Patients younger than 15 still have open growth plates which could be damaged by surgery, and those older than 50 usually already have arthritis, which would be made worse with a surgical procedure. One needs to realize that over 50% of people who sustained ACL injuries unfortunately, will experience early knee arthritis within 5-10 years, whether surgery is performed or not. The risk is even higher if cartilage &/or meniscus are also injured. If a bone bruise occurs as well, then knee pain could continue for longer (several weeks or months), especially once an athlete resumes impact activity.


Another factor contributing to the ultimate #surgical decision is whether or not one wants to return to a certain sport or work activity. The ACL, once torn, cannot heal on its own nor be surgically repaired. Scar tissue will form and the knee will continue to be unstable, unless intensive physical therapy rehab exercises are performed daily, to strengthen surrounding musculature to support the knee joint, which will take at least 3-6 months. If surgery is performed, the surgeon has to “harvest” tissue from another part of the knee, or use a donor cadaveric graft to reconstruct or replace (make) a new ACL. After surgical ACL reconstruction, a big, long hinged knee brace will be used for a couple of months. This will protect the joint during the early healing period. #Physicaltherapy will again be prescribed, 3-5 times a week for ROM and strengthening. At first, aquatic or water rehab exercises will be instituted, since this is safer on joints rather than land therapy. The post-operative bracing is then switched out for a lighter, shorter fiberglass type brace that will be worn for several more months. This “sports”, or functional brace, needs to be used during any type of athletic activity for several months, to protect the knee with pivoting or side-to-side maneuvers, even after the ACL graft is fully healed and all muscles have returned to their pre-injury level.


After 8-10 months, a “functional” exercise test is usually performed by a licensed physical therapist, to determine whether or not the operated lower extremity is strong, agile and powerful enough (compared to the opposite side) to withstand athletics/sporting activities. After initial healing, it takes up to a year or more for the ACL graft to take on normal knee tissue properties, a process called remodeling. Proprioception, or sense of where the knee is in space, is the last to return, along with psychological fear of reinjury. The best prevention of repeat trauma to the same knee is to rehab hamstrings, since this muscle group is protective against ACL tears. One also needs to perform balance exercises on one leg, to regain proprioceptive or positional stability. If the sport involves jumping &/or running, techniques of landing/stopping will also need to be practiced to tolerate rotational forces.


In summary, whether surgery is performed or not, an ACL tear is a devastating knee injury which takes a few to several months to recover. The mainstay of treatment for ACL injuries is intermittent bracing, along with physical therapy rehab exercises (aquatic and land) to regain ROM and strength (especially of the hamstrings). Focus on single leg balancing work along with landing/stopping techniques will also benefit the joint for successful healing/recovery. The ultimate goal is to prepare the knee for functional return to preinjury level/status, allowing resumption of previous level of play in competitive athletics!

#September2015

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