Hole Bearing Sliding

Hole Bearing Sliding

ACL Reconstruction by Jon Tobey

 

 

 

                                               ACL Reconstruction by Jon Tobey

 

 

An anterior cruciate ligament (ACL) injury can occur from both a contact and noncontact mechanism.  The most common contact cause of the injury is a blow to the lateral side of the knee resulting in a valgus force to the knee.  The most common noncontact cause of the injury is a rotational mechanism in which the tibia is externally rotated on the planted foot.  "Literature supports that this mechanism can account for up to 78% of all ACL injuries."  The second most common noncontact cause is forceful hyperextension of the knee. (Colby & Kisner, 532)  ACL injuries are common in sports including: basketball, field hockey, football, gymnastics, skiing, soccer and volleyball. (Childs, 2002) 

 

An ACL injury is one of the most common and expensive ligamentous knee injuries.  "There are more than 250,000 ACL injuries in the United States each year, or 1 in 3000 people." (Childs, 2002)  The ACL is a cruciate ligament that provides the knee with movements such as flexion, extension and sliding movements.  The ACL along with other ligaments assists with proprioception and neuromuscular function of the musculoskeletal system.  An ACL injury can occur if the tibia is externally rotated on a planted foot. Also if there is internal tibial rotation on a planted foot with a valgus stress.  The dynamic muscular stablaizers of the knee including the quadriceps and hamstrings can affect the anterior displacement of the tibia relative to the femur causing a biomechanical ACL failure.  The ACL also has receptor sites for estrogen, progesterone and relaxin.  In the female athlete these hormones fluctuate in relation to the menses, research shows that estrogen affects the laxity and increases risk of ACL injury in females. (Childs, 2002) 

 

There are several signs and symptoms that will arise with a severe and sudden ACL injury.  Feeling or hearing a pop sound coming from the knee when the injury occurs.  If there is sudden instability in the knee, including a buckling or the knee giving out after a sudden jump, change of direction or a force directly to the side of the knee.  Pain in the back of the knee or on the outside of the knee is a sign of ACL injury.  Any swelling of the knee with in the first few hours that the injury occurred could be a sign of hemarthrosis (bleeding inside the joint).  If swelling of the knee occurs suddenly this is usually a sign of serious injury.  Limited range of motion of the knee due to swelling or pain could also be linked to an ACL injury.  Usually after an ACL injury occurs one is able to walk on the knee, but the activity that caused the injury must stopped immediately. (ACL injury, 2006)

 

The ACL is the most common knee ligament that needs to be surgically repaired due to frequent injury of this area.  Before surgery is performed functional goals are set in a rehabilitation program and if the joint does not meet specific criteria after this program is finished and degenerative changes of the joint become apparent then the patient will be recommended for surgical intervention. There are usually two types of reconstruction surgeries used to restore stability to the knee.  The most successful intervention used is the inra-articular reconstruction, this procedure involves the use of an autograft (comes from your own body), allograft (comes from someone who has died) or a synthetic graft.  The grafts used in most cases come from the patellar tendon, the graft made up of the middle third of the patellar tendon and small pieces of bone from the knee cap and shin bone. (Rouzier, 2006)  The procedure of this type of surgery begins with  the doactor making an incision which is one to three inches below the kneecap.  Using an arthroscope to view the patients knees the doctor will begin drilling holes in the femur and tibia and removing the torn ACL.  Then the graft is passed through the drilled holes to replace the torn ACL.  The graft is then anchored in place using screws or staples.  The incisions from the graft site will then be closed with stitches tape or staples. (Rouzier, 2006) 

Extra-articular reconstruction procedures can also be used.  These procedures involve the transposition of dynamic musculotendinous stabilizers or inert restraints around the knee including the gracilis, semitendinosus muscle, capsular ligament, or IT band, which are designed to provide external stability to the knee joint. (Colby & Kisner, 535)  This type of procedure is primarily used along with intra-articular reconstruction rather than by itself due to the fact that the procedure does not restore normal arthrokenematics to the knee by itself.  It is also used in adolescents who have not reached bony maturity and still have open epiphyses. (Colby & Kisner, 536)

 

In order for the knee to return to its full function a strict rehabilitation program will be needed.  This program involves four phases, the maximum protection phase, moderate protection phase, minimum protection and return to activity phase.  The maximum protection phase begins usually the day after surgery and will last up until four weeks after surgery.  During this phase quadriceps, hamstrings, and hip adductors will be worked immediately while controlling the level of pain.  Low intensity, multiple angle isometrics of the knee musculature will be used along with stabilization exercises to develop stabilization in the involved leg and increase weight bearing exercises involving the knee.  In some cases electrical stimulation or biofeedback is used to augment quadriceps contractions.  These methods are used to prevent reflex inhibition and atrophy of knee musculature.  In order to regain mobility therapist-controlled PROM or A-AROM methods are used along with supine wall slides, supine gravity assisted knee extension exercises, and patellar glide exercises. Next the patient will begin to restore dynamic control and strengthen the knee musculature.  This will be done by using techniques such as heel slides, squats with a knee brace, assisted and active knee flexion and extension exercises.  Pool exercises will be added once the incision site has healed and stationary cycling will be used to increase cardiovascular endurance. (Colby & Kisner, 540) The moderate protection phase usually begins at about the fourth or fifth week postoperatively.  During this phase the patient will begin to regain full ROM of the knee using proper stretching and joint mobilization techniques.  The patient work on increasing strength, control and endurance of the lower extremities using exercises including wall slides against resistance, and unilateral squats on an incline sled.  The patient will also improve proprioception, balance and stability with standing on unstable surfaces and their cardiorespiratory fitness with aerobic conditioning activities. (Colby & Kisner, 541)  The last phase is the minimum protection and return to activity phase which usually starts 10 to 24 weeks postoperatively.  During this phase the patient will be involved in progressively demanding functional activities including jogging, stair climbing and agility drills.  A knee brace will still be worn during this phase while involved in vigorous activity that includes twisting, turning or light jumping motions.  Plyometrics and medium and high-velocity spectrum isokinetic exercises will also be added to the rehabilitation program.  Usually by 24 weeks the patient will return to their preinjury activity level, although during high-demand vigorous activity functional bracing may still be needed. (Colby & Kisner, 541) 

 

 

 

 

 

 

 

 

 

 

 

 

References

 

Childs, G. Sharon. (2002) Pathogenesis of Anterior Cruciate Ligament injury. Orthopaedic Nursing. Vol. 21 (4) p35 http://web.ebscohost.com/ehost/detail?vid=22&hid=21&sid=ef28bf25-597b-4378-a80c-32c460c4cbce@sessionmgr2

 

Colby, L.A. Kisner, C (2002) Therapeutic Exercise foundations and Techniques.  F.A. Davis Co. Philadelphia.

 

Rouzier, P.  (2006) Clinical Reference Systems: Anterior Cruciate Ligament (ACL) Reconstruction. Mckesson Provider Technologies. http://web.ebscohost.com/ehost/detail?vid=8&hid=14&sid=675c2122-e935-4025-86b7-bb240f78abab@sessionmgr7

 

Web MD (2006) Anterior Cruciate Ligament (ACL) Injuries: Symptoms. http://www.webmd.com/a-to-z-guides/Anterior-Cruciate-Ligament-ACL-Injuries-Symptoms

About the Author

http://www.sac-nh.com/specialized_programs.php http://www.sac-nh.com/personal_trainers.php http://www.sac-nh.com/contact_tobey.php http://twitter.com/#!/JonathanTobey

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