Knee Arthroscopy- ACL Reconstruction
Knee arthroscopy, keyhole surgery, is a technique used to inspect the inside of the joint cavity to diagnose and assess damage and, where possible, to treat this damage. Arthroscopic knee surgery involves putting a small telescope and special instruments into the knee, with the ability to photograph and video the operation. Arthroscopic knee surgery is used to treat any number of conditions that occur within the knee from simple cartilage tears to removal of loose bodies, meniscal surgeries and anterior/ posterior cruciate ligament reconstructions. At the same time all of the other structures within the knee can be clearly viewed and probed.
The four main ligaments in the knee connect the Femur (thighbone) to the Tibia (shinbone) and include the following:
• ANTERIOR CRUCIATE LIGAMENT (ACL): The Ligament located in the center of the knee, which controls rotation and forward movement of the Tibia.
• POSTERIOR CRUCIATE LIGAMENT (PCL): The Ligament located in the center of the knee, which controls backward movement of the Tibia.
• MEDIAL COLLATERAL LIGAMENT (MCL): The Ligament that gives stability to the inner knee.
• LATERAL COLLATERAL LIGAMENT (LCL): The Ligament that gives stability to the outer knee.
WHAT IS DONE?
The entire procedure is done with the help of 2-3 small keyhole sized incisions from which the instruments and the small laser/telescopic camera is inserted and the procedure is visualized on a high definition screen.
Arthroscopic ACL/PCL reconstruction: The torn portion of the anterior cruciate ligament or the Posterior cruciate Ligament is removed. A new ligament graft is taken from the extra tendon of hamstrings group of muscles and after preparation is inserted into the Femoral (upper bone) and the Tibial(lower bone) tunnel.
Arthroscopic MCL/LCL repair with augmentation: The torn portions of the ligament are repaired with sutures. In order to further strengthen the repaired ligaments, an augmentation (extra support) is done with additional grafts obtained from the extra tendons of Hamstring (knee) or Peronei (ankle) group of muscles.
PRE-OPERATIVE STEPS
Though the procedure is a very minor procedure, every effort is made to assess the patient prior to surgery in order to ensure safety of the patient for the elective procedure.
1. After admission, routine blood work-up will be done prior to surgery. Depending on the age of the patient and other premorbid conditions, other investigations such as Echocardiography may be performed.
2. All the investigations prior to surgery are performed in order to ensure that the surgical procedure can be safely tolerated by the patient, since it is an elective procedure. If any risk is involved, the patient/ attendants will be informed so.
3. X-rays and MRI may be done depending on the surgeon’s choice and the surgical indication for the procedure.
4. Surgical consent will be explained to the patient detailing the procedure as well as the risks involved, if any.
INTRA-OPERATIVE STEPS
ACL/PCL Reconstruction
Procedure for the reconstruction of ACL and PCL is almost the same except the position of the femoral and tibial tunnels are different. An ACL injury is about 100 times more common than a PCL injury. Here we are describing the steps for an ACL reconstruction.
1. The inflow cannula, which brings the fluid into the joint so that the knee may be visualized, is seen in this picture. The patella is at the top of the screen and the trochlear groove of the femur at the bottom. The width of the tube is approximately 4 mm (1 inch = 25.4 mm).
2. The apparently normal meniscus is viewed. The femur is above the meniscal cartilage and the tibia is below it. A probe is inserted to inspect the meniscal cartilage.
3. The normal ACL is a taut rope-like structure which goes from the femur to the tibia. Probing of this ACL indicates that it is lax and frayed. This indicates a functionally incompetent ACL (torn ACL).
4. To reconstruct the ACL, it is necessary to remove all of the existing damaged ACL. This is done with a motorized device which is called a shaver.
5. At this point, attention is directed to the hamstring tendon. Incisions are made at the inner aspect the upper 1/3 leg. Each incision is approximately 1.5 inches in length.
6. After making the skin incisions, the tendon is identified, and is harvested with a tendon stripper. Harvesting is completed. 8. The graft then has sutures placed through the bone blocks.
7. Attention is then directed to the arthroscopic part of the procedure. The tibial drill guide is positioned on the tibia.
8. The guide wire is then drilled into the tibia, exiting inside the joint.
9. The tibial drill hole is placed.
10. The endoscopic femoral drill guide is then passed.
11. The guide is then positioned on the back of the femur.
12. The femoral guide wire is then placed, the femoral guide is removed and the femoral drill is used to place a hole in the femur.
13. The graft is then placed through the tibia, through the knee joint, and into the femoral drill hole.
14. For the graft to heal, blood vessels must grow into the reconstructed ACL. To hold the graft in place, a endobutton attached to the graft is inserted through the femoral drill hole. This particular screw is a bioabsorbable screw.
15. A second screw is inserted into the tibia to hold that part of the reconstruction in place. Following this, the reconstructed ACL is inspected. Unlike the picture of the torn ACL, the reconstructed ACL is a rigid rope-like structure that provides stability to the joint.
16. At this point the procedure is finished, the incisions are closed, and the surgical procedure is completed.
POST-OPERATIVE MANAGEMENT/ REHABILITATION
ACL Reconstruction
Rehabilitation is a vital part of your ACL recovery and is essential to getting back to regular physical activity. Your program can last anywhere from two to six months or longer. Your doctor will help you find a program that is suited to your recovery goals.
Weeks 1 - 2
• Ice/elevation every 2 hours for 15 minutes to minimize edema and promote healing (please refer to Icing handout).
• Full weight bearing is allowed immediately after surgery. Though some surgeons may prefer not to allow weight bearing for up to 6 weeks after surgery.
• ROM knee brace needs to be worn for support.
• Dressing will be done on day 4 after the surgery.
Exercises
• The patient should be seated at the edge of bed and asked to hang the knee for flexion; lift for knee extension.
• Quad sets/straight leg raises, hip abduction, calf presses, glut sets, and core exercises.
• Upper body conditioning, non-operated leg stationary cycling.
Goals
• Knee Range of motion: 0-90 degrees.
• Good quality gait with least amount of Assistive Device.
Weeks 2 - 4
• Suture removal on day 14.
• Walking for exercise for 15-20 minutes if no limp or swelling present.
Manual
• Extensive patellar mobilization.
• No direct scar mobilization x 4weeks.
Exercises
Range of motion and functional strengthening exercises:
• Squats/Leg Press, Bridges/Hamstring Curls.
• 2” step up/down, intense core training.
• Aerobic exercises as tolerated (bilateral stationary bike, Elliptical, arm bike).
Goals
• Active range of motion equal extension to uninvolved side and flexion to 120 degrees. No edema. Full weight-bearing; normal gait without assistive device. Single leg balance 60 seconds on level surface.
Weeks 4 - 6
• Review with the doctor at 4 weeks.
• Walk up to 1 hour for exercise.
Manual
• Continue with soft tissue mobilization. Apply direct scar tissue mobilization; can use instruments/tools.
Exercises
• Emphasize self-stretching to both lower extremities.
• Increase intensity of resistance exercises (i.e. standing resisted squats, lunges, etc.).
• Introduce eccentric exercises (4-6” steps).
• Increase single leg strength, challenge proprioceptive training.
Goals
• Full Range Of Motion equal to uninvolved leg.
• Perform 4 inch step down.
• Bike with minimal resistance for 20-30 minutes (in saddle), walking for 30 minutes, Elliptical, water-walking.
Weeks 6 - 10
Manual
• Soft tissue mobilization and joint mobilization as needed.
Exercises
• Add lateral training exercises (lateral step ups, lunges, step overs).
• Initiate tri-planar activities with the exception of closed-chain rotation (pivots).
• No cutting or pivoting.
Goals
• Activities should be pain-free:
• Able to descend stairs, double leg squat hold for >1 minute.
• Bike >30 minutes with moderate resistance, Elliptical with interval training.
Weeks 10 - 16
• Doctor visit at 3 months.
• Incorporate bilateral, low level jumping exercises.
• Continue to increase strength, endurance, and add sport specific training drills.
Weeks 16+
• Doctor visit at 6 months.
• Implementation of jump training, agility training.
• After 6 months add lateral plyometric type drills, agility ladder
Goals
• Initiate sagittal plane plyometrics, work towards single leg plyometrics. Clearance by surgeon before returning to full athletics.