Lateral collateral ligament injury of the knee

　　1. Etiology

　　Due to the violent action on the inner side of the lower leg, causing it to be adducted.

　　2、发病机制

　　2. Pathogenesis

　　Patients with lateral collateral ligament injury of the knee may be complicated with fibular head fracture and common peroneal nerve injury. Ligament injury affects the patient's daily life and endangers the patient's health, so once an injury occurs, it must be treated in time.

　　1. The knee LCL rupture often occurs at the insertion site, most of which are accompanied by avulsion fracture of the fibular head, so the main clinical symptoms are limited pain on the lateral side of the knee joint, swelling near the fibular head, subcutaneous ecchymosis, local tenderness, limitation of knee joint movement, and sometimes accompanied by injury of the common peroneal nerve.

　　1. The result judgment of the stress test of knee varus stress: When the test is negative in the straight position and positive in the 30° flexion position, it indicates that the knee LCL rupture is accompanied by the posterior 1/3 of the lateral joint capsule ligament, the bow-shaped ligament, and the popliteal tendon injury; When both the straight position and the 30° flexion position are positive, it indicates that the knee LCL rupture is accompanied by the cruciate ligament rupture; When the test is positive in the straight position and negative in the 30° flexion position, it indicates that the knee LCL rupture is simple or loose.

　　The main cause of the onset of lateral collateral ligament injury of the knee is due to sports trauma, and there is currently no effective preventive measures. Preventing sports injuries, doing warm-up before exercise, and early detection and early diagnosis are the key to the prevention and treatment of the disease.

　　The examination of lateral collateral ligament injury of the knee mainly includes: The knee X-ray film shows avulsion fracture of the fibular head, anteroposterior knee X-ray film in the position of internal adduction of the lower leg, the lateral joint space of the knee is significantly widened, which is of great value in judging the degree of injury of the external LCL.

　　What kind of food is good for the body with lateral collateral ligament injury of the knee: It is advisable to have light diet and reasonable diet combination. Pay attention to the rationality of dietary structure, rich nutrition, increase the intake of protein-rich foods, which is helpful for ligament recovery.

　　1. Treatment

　　1. Non-surgical treatment

　　Applicable to patients with mild knee LCL injury, knee internal adduction stress radiography, joint space widened by 0.4cm, can be compressed with elastic bandage; When the joint space is widened by 0.5 to 1.2cm, it is given to completely remove the blood in the knee joint and apply pressure bandage, fixed with anterior and posterior long leg plaster splint in the 20° to 30° flexion position of the knee, the cast is removed after 6 weeks, and the knee joint movement exercise is started. During the period of cast fixation, the quadriceps muscle contraction training should be strengthened.

　　2. Surgical treatment

　　(1) Fresh patellar lateral collateral ligament (LCL) injury: For cases of patellar LCL insertion avulsion fracture of the fibular head, a straight incision 2 to 3 cm above and below the fibular head is used, maintaining the connection between the fracture piece and the lateral collateral ligament of the knee, reducing the displaced avulsion fracture piece, and fixing it in place with a screw. For cases of simple LCL rupture in the middle, a straight incision on the lateral side of the knee is used, 4 to 5 cm long, carefully separate, find the two ends of the LCL, pull the two ends tight in a 30° flexed knee position and suture them together. If the lateral collateral ligament is lax, an overlapping suture can be performed.

　　(2) Chronic patellar lateral collateral ligament (LCL) injury: ① For cases of knee instability caused by patellar LCL laxity, perform patellar LCL tightening using the Augustine method: a straight incision or S-shaped incision on the lateral side of the knee, 5 to 6 cm long, chisel off the cortical bone at the origin of the patellar LCL on the lateral condyle of the femur (1.5 cm × 1.5 cm in size), dislocate it upwards (near) by 1 to 2 cm and tighten it, then cut off the corresponding small piece of cortical bone layer with a bone chisel, make it rough, and secure the cortical bone of the ligament origin with a screw. In addition, on the basis of the above method, the lateral head of the gastrocnemius muscle can also be cut off from the origin and moved forward to suture it together with the origin of the displaced patellar LCL to strengthen the ligament. ② For cases of posterior lateral rotational instability caused by patellar LCL rupture and cruciate ligament injury, patellar LCL tightening and iliotibial band transfer surgery can be performed using the Augustine method. The iliotibial band insertion is cut off mostly at the lateral condyle of the tibia and freed proximally by 3 cm, the cut end of the iliotibial band is moved to the head of the fibula, tightened, and sutured and fixed with silk thread. ③ For cases of anterior lateral rotational instability of the knee joint caused by patellar LCL rupture, there are several surgical methods, including: one is the patellar LCL insertion advancement procedure: a straight incision on the lateral side of the knee is used, the insertion points of the patellar LCL and the biceps femoris on the head of the fibula are longitudinally chiseled off and flipped upwards, exposing the posterior lateral joint capsule of the knee, the loose posterior lateral joint capsule is pulled down and sutured in an overlapping manner, the knee is flexed to 30°, and the chiseled-off insertion points of the patellar LCL and the biceps femoris are pulled tight and moved to the lateral condyle of the tibia, fixed with a screw. Another is the biceps femoris suspension procedure (Kromer method): an S-shaped incision is made on the lateral side of the knee, the lower end stopping at the head of the fibula, 8 to 10 cm long, the insertion point of the biceps femoris is retained, the anterior 1/3 to 1/2 of the biceps femoris tendon is separated, the separated anterior part of the biceps femoris tendon is cut off at the level of the origin of the patellar LCL, the cut-off anterior 1/3 to 1/2 of the biceps femoris tendon is moved forward to the origin of the LCL and tightened, sutured and fixed in a 30° flexed knee position. In severe cases of anterior lateral rotational instability, the biceps femoris tendon should be moved forward more. In severe patients, the proximal part of the cut-off biceps femoris tendon can be moved forward to the lower outer corner of the patella, tightened, and sutured and fixed to the lateral margin of the patellar tendon.

　　II. Prognosis

　　Generally, the prognosis is good after surgical treatment.