ACL Reconstruction: What Patient's Need to Know

Summer is a great time to get outside and be active, but an injured ACL can slow down your summer fun. Dr. Bob Wolf, orthopedic surgeon at Brookwood Baptist Medical Center, writes this week's guest blog about what patients need to know about ACL reconstruction.

ACL (anterior cruciate ligament) reconstruction is performed on approximately 100,000 people each year in the United States. It is one of the more common knee injuries sustained in athletic competition ultimately requiring surgical treatment. What should a patient know when they are forced to make decisions on such an injury?

Ligaments are the soft tissue structures which connect bones together and provide mechanical restraint to excess motion in a joint. The ACL is the ligament which connects the femur (thigh bone) to the tibia (shin bone) and prevents excessive anterior translation thereof (tibia slipping out in front of the femur). This checkrein may be torn during both contact and non-contact injuries, often with associated knee damage (meniscus tears, medial collateral ligament injuries). Football, basketball, and soccer are the most common team sports involved, but ACL tears are also seen in individual sports such as tennis, snow and water skiing, BMX, and any other activity where rapid changes in direction are demanded. In an athletic individual who wishes to continue to participate in sports, surgical reconstruction is generally appropriate. The reasons for this are twofold. First, a patient with an ACL tear will most likely experience recurrent instability during athletics, and often in lower level activities of daily living, without surgical reconstruction. The symptoms of this (pain, swelling, giving way) impair function, and are usually alleviated with successful surgical treatment. Additionally, restoring knee stability with surgical reconstruction protects the meniscus and other structures which are damaged during episodes of instability, and may prevent the progression of arthritis.

ACL surgery entails arthroscopy (insertion of a 4 mm camera into the knee through small incisions), repair of associated meniscal, ligament, or articular cartilage injury, and reconstruction (replacement) of the ACL with a tendon taken from another part of the knee or from a tissue donor (allograft). The tendon is placed into bone tunnels in the femur and tibia, which are drilled in an arthroscopic-assisted fashion, where the ACL previously existed. The tendon graft may be fixed with a variety of devices, usually small screws, placed in the bone arthroscopically. These hold the graft in place until your body converts it into a new ACL, which takes about 6-12 months. The screws are generally left in place permanently. The tendon graft is usually taken from the middle 1/3 of the patellar tendon (tendon connecting knee cap to tibia), medial hamstrings (tendon along inner thigh), or from a tissue donor. When a tissue donor is used, better functional results are seen with fresh-frozen non-irradiated patellar tendon grafts. Allografts which are irradiated have impaired biomechanical function, and soft tissue allografts (hamstrings/tibialis anterior/achilles) have shown inferior clinical results in medical literature – these are not recommended as a result. Quadriceps tendon autograft may be a reasonable alternative, but there is insufficient clinical data to compare it to the above grafts. Stem cell augmentation is unproven at this time, is expensive, and has been shown to impair function in some studies. There are risks and benefits to each graft, and choice usually depends on age, prior knee injury status, level of athletic expectation, cosmesis, and rehab expectations/capacity in terms of pain. Your surgeon should be able to guide you to the choice which best suits your individual expectations.

The surgery is usually done on an outpatient basis, with the patient going home the same day as the procedure. Rehab involves aggressive exercises performed on a daily basis, emphasizing knee flexibility and strengthening, usually overseen by a physical therapist. Patients can often begin running at 2 months after surgery. In general, ACL reconstruction is one of the most successful procedures we perform as orthopedic surgeons, with 90-95% of patients being able to return to cutting/pivoting sports at 6 months after surgery. Be sure that your surgeon has adequate training in this technique (fellowship training in orthopedic sports medicine is helpful), and if you have unanswered questions seek a second opinion.

Thank you to Dr. Bob Wolf, orthopedic surgeon at Brookwood Baptist Medical Center, for writing a guest blog this week.

To make an appointment with Dr. Wolf or any of our orthopedic physicians, please click here to find a physician near you or call (833) 249-5221.