Fig. 2.1
Anesthesiologist performing spinal block
Peripheral nerve blocks place local anesthetic directly around the major nerves in the thigh, such as the femoral nerve or the sciatic nerve. These blocks numb only the extremity that is injected. One option for a peripheral block is to perform a one-time injection around the nerves in order to numb the extremity just long enough for the surgery. Another option for this type of block is to keep a catheter in place, which can deliver continuous local anesthesia around the nerves for up to several days after surgery. Regional anesthesia has many advantages, including causing less nausea and drowsiness, improved pain control after surgery, and reduced risk of serious medical complication that may occur with general anesthesia.
2.4 General Anesthesia
General anesthesia is often used for major surgery, such as a joint replacement, but in some centers it is used also for knee ligamentous reconstruction. General anesthesia may be selected based on patient, surgeon, or anesthesiologist preference or if the patient is unable to receive regional or local anesthesia. With general anesthesia, the anesthesiologist administers medication through injection or inhalation. The anesthesiologist will also place an endotracheal or laryngeal tube in the throat and administer oxygen to assist breathing. General anesthesia affects both heart and breathing rates, and there is a very small risk of serious medical complications, such as heart attack or stroke.
2.5 Prophylactic Antibiotics
Knee arthroscopies have a very low rate of infective complication when only a diagnostic procedure or a simple meniscectomy is performed, and according to the recent literature, there is no evidence of usefulness of antibiotics in these simple procedures. Bert et al. reported an infection rate of 0.15 % when prophylactic antibiotics were used compared to 0.16 % in patients who underwent surgery without an antibiotic prophylaxis. Infection is a relatively rare but potentially serious complication after anterior cruciate ligament reconstruction. Many risk factors have been described, including smoking, obesity, and diabetes. Antibiotic prophylaxis appears to be the safest way to prevent postsurgical infections. In many hospitals 2 g of a second-generation cephalosporin is used with a significant reduction of infective rates [3–5].
2.6 Thromboprophylaxis
Incidence of venous thromboembolism after arthroscopic ACL reconstruction is described in literature with a percentage between 1.7 and 4 %. In clinical practice different protocols are used ranging from nothing to low molecular weight heparin in all patients. Further research is recommended to assess the need for thromboprophylaxis in patients undergoing ACL reconstruction, especially when risk factors are present [6, 7].
2.7 Patient Positioning
Patient positioning is a crucial part of surgery, and incorrect placement can result in prolonged surgical times and unexpected complications. Patient positioning is variable, based upon surgeon’s habits and the instruments available in the operating theater. There are a few important concepts that we will highlight that may make procedures fast and efficient.
The patient is positioned with the heels at the end of the table for easy access and manipulation. The pelvis is moved on the side of the bed on the side of surgery, with the trochanteric region on the border of the surgical bed. A good practice is to position a safety belt well attached to the bed, at pelvis level, to block the patient from unexpected movements.
Depending on the surgeon’s preference, a tourniquet is positioned high on the thigh to permit a comfortable surgical field preparation and avoid distal migration of it. The tourniquet must be placed snug but not tight. Before positioning the tourniquet a soft cotton padding material is rolled on. The tourniquet pressure is usually set between 300 and 350 mm/hg for a normal adult man or female and is activated when the sterile field is ready. Many articles have been written about tourniquet usefulness in arthroscopic surgery. Arthroscopic anterior cruciate ligament reconstruction with a tourniquet was significantly associated with less operative visualization difficulties (p < 0.05), compared with surgery without a tourniquet. There were no significant differences in visual analogue scale pain, blood loss, operation time, and complications between the two groups as evidenced by many studies [8, 9]. One recent study demonstrated that tourniquet use did not affect rehabilitation, return to activities, and muscle damage after arthroscopic meniscectomy [10].
After the positioning of tourniquet, a plastic drape can be placed to protect the tourniquet and the patient from the preparation solution. After this step there are two different options for preparing the patient, using the circumferential leg holder or a lateral post. In the first case the leg holder is attached close to the thigh, the strap is placed, and the foot of the bed is lowered or removed depending on the table type. The surgeon or an assistant must check that the leg can be moved to obtain a correct visualization of the medial and lateral compartments of the knee. If the surgeon works without an assistant, the leg can be positioned in valgus for medial arthroscopy or (Fig. 2.4) for lateral arthroscopy.
Some surgeons prefer a lateral post instead of a leg holder (Fig. 2.2). Posts are available in many designs, curved or flat, fixed or with a small rotational movement. The post can be removed, and the leg flexed down the side of the table in order to perform surgery of the intercondylar notch. The lateral compartment is well exposed, positioning the leg in a four position, with the foot positioned across the contralateral leg and the knee flexed at 90°. Additional force can be applied to the medial knee to further open the lateral compartment.
