Gordon W. Nuber

Indications

1. Active individual with an acute torn anterior cruciate ligament (ACL)

2. Individual with recurrent instability who has failed rehabilitation and bracing

3. A sedentary individual who displays instability related to his or her anterior cruciate ligament-deficient knee with daily activities

Contraindications

1. Active knee infection

2. Lack of neurovascular control

3. A sedentary individual without demonstrable instability

4. Older age (relative)

5. Pediatric patient with open growth plate

Preoperative Preparation

1. Knee radiographs: anteroposterior (AP), lateral, and skyline

2. Magnetic resonance imaging (MRI): not a necessity, but helps to assess other injuries.

3. Wait for knee swelling and active range of motion to normalize prior to surgery (may necessitate preoperative physical therapy).

Special Instruments. Position, and Anesthesia

1. Position the patient supine on the operating room table.

2. The contralateral extremity should be padded to avoid pressure on susceptible areas.

3. Leg holder or post

4. General, epidural, or spinal anesthetic

5. Routine arthroscopic setup and routine orthopaedic surgical instruments

6. Tibial and femoral alignment guides for positioning the tunnel guide pins

7. Interference screws for graft fixation; these can be metal or bioabsorbable. A screw and washer may be used as a “post.”

8. A tendon passer (either wire loop, Hewson tendon passer)

Tips and Pearls

1. The anterior knee incision should extend from the lower pole of the patella to a point slightly medial to the tibial tubercle.

2. The lateral incision extends proximal from the lateral epicondyle, approximately 2 to 3 cm.

3. Examine the knee under anesthesia. Assess the stability and document.

5. The tibial hole should enter the joint at the posterior insertion of the anterior cruciate ligament’s remnant. This is just anterior to the posterior cruciate ligament.

6. The femoral guide pin enters the joint within 5 to 6 mm of the intercondylar notch’s back wall. This corresponds to an 11 o’clock position on a right knee and a 1 o’clock position on a left knee.

7. Make an adequate notchplasty to optimize visualization of the drill holes.

8. Rasp the ends of the tunnels to avoid sharp edges.

9. Use a “carrot” to plug the tibial tunnel and avoid fluid extravasation after the tunnel is created.

10 Use a rongeur to contour the end of the bone plug into a bullet; the tip aids graft passage.

11. Minimize tourniquet use if possible.

12. In most cases, aim to harvest 25-mm-long bone plugs from the patella and the tibia.

13. Insert the interference screw with the use of a guide pin.

14. If a meniscal repair is indicated, this should be performed prior to the anterior cruciate ligament reconstruction.

What To Avoid

1. Minimize the chance of patella fracture by avoiding excessively long or deep bone cuts.

2. Lift the femoral guide’s handle to avoid breaking out the back wall while creating the femoral tunnel.

3. Take care to minimize the chance of dropping the graft on the floor.

Postoperative Care Issues

1. Consider placing a suction drain in the lateral incision.

2. Place the leg in a compressive dressing with an elastic wrap after surgery. Consider cryotherapy.

3. If a continuous passive motion (CPM) machine is used, it can begin at 0 to 40 degrees on day 1 with daily incremental increases of 5 to 10 degrees.

4. A hinged brace can be used when ambulating the first 4 weeks after surgery. Lock the brace in extension for 2 weeks, then unlock and allow free range of motion for 2 weeks. Alternatively, a knee immobilizer can be used for the first few weeks after surgery (commonly the first 2) and then discontinued when the patient regains adequate quadriceps control.

5. An accelerated rehabilitation protocol begins immediately after surgery. Normally, active and active-assisted flexion exercises and passive extension exercises are instituted.

6. Patients commonly either go home the day of surgery or spend one night in the hospital.

7. Protected weight bearing as tolerated with the immobilizer or hinged-brace is allowed after surgery. Most patients can wean themselves off crutches during the first 2 weeks postsurgery.

Operative Technique

1. Position the patient supine on the operating room table. Apply a thigh tourniquet as proximal as possible on leg. Place the opposite leg on a bolster to flex the hip and avoid stretching the femoral nerve. In addition, loosely tape the opposite leg to the table (the leg of a large athlete may fall off a narrow operating table).

2. Examine the knee and leg after adequate anesthesia is obtained. This examination under anesthesia (EUA) should assess medial, lateral, anterior, and posterior knee stability prior to applying the leg holder. Document the examination.