Outline:
There are tough medial and lateral collateral ligaments attaching in the both sides of knee joint. When the knee is flexed, the ligaments are relaxed and the knee joint slightly adducts and abducts; when the knee joint is extended, the lateral ligaments are tense, there is no sideways movement of the knee joint. When the knee is in a straightened position and the knee joint is forced to hyperevert by the strike of a violent force or the compression of a heavy object on the knee or the lateral side of leg, it may result in injury or rupture of medial accessory ligament. Occasionally, in the case of hyper-inversion of the knee joint caused by a violent force, there may occur an injury or rupture of lateral accessory ligament. Injury of collateral ligament seldom occurs alone, it is often accompanied by the injuries of the capsule of knee joint, the cruciate ligament and the semilunar plate.


Major points for diagnosis  
1. There is a definite traumatic history of the knee.

2. There are local swelling, pain and ecchymoses, dysfunction of the knee joint in flexion and extension.
 
3. There is a remarkable tenderness at the internal epicondyle of femur in the case of injury of medial collateral ligament, and at the lesser head of fibula or external epicondyle of femur in the case of injury of lateral collateral ligament. The test of sideways movement of knee joint is positive.

4. Under local anesthesia, an orthophoric X-ray film of the inversion or eversion knee may reveal the enlargement of join space at the part of injured ligament, or whether there is a complication of fracture.


Treatment  
Tendon-smoothing manipulation:
For the case of partial laceration of collateral ligament, at first visit, one time extension and flexion of the knee joint should be done to restore the slight transposition and relax the fascia. But this manipulation should not be done repeatedly for fear of aggravating injury. After the acute symptoms disappear, the manipulation for removing adhesion may be taken to restore the articular function. First, the operator applies kneading, massage and rubbing manipulations on the tender point on the lateral side of the knee joint, then, applies smoothing and relaxing tendon manipulations along the course of the collateral ligaments. Finally, the operator presses and kneads the injured part with the hand and fingers holding the knee while swaying and rotating the leg with the other hand grasping the ankle, at the same time, in combination with pulling and flexing the hip and knee manipulation.

Fixation:
For the case of partial rupture of collateral ligament, the sick knee should be wrapped with elastic bandage for rest, or fixed with a plaster support or splints in a functional position with the knee joint bent at the angle of 200 to 300 for 3 or 4 weeks.


Herbal therapy  
Internal treatment based on syndrome differentiation  

(1) Syndrome of stagnant blood blockage
Main symptoms and signs:
Serious pain in the knee with swelling, difficulty in walking, or ecchymoses on the tongue, stringy or thready-choppy pulse.
 
Therapeutic methods:
Promoting blood flow to remove the stasis, activating qi flow to stop pain.

Recipe and herbs:
Modified Taohong Siwu Decoction. Specifically, Chaihu (Radix Bupleuri)6 g, Honghua ( Flos Carthmi )6 g, Danggui ( Radix Angelicae Sinensis )10 g, Chishaoyao ( Radix Paeoniae Rubrae )10 g, Taoren ( Semen Persicae )10 g, Zhike ( Fructus Citri Aurantii )10 g, Ruxiang ( Gummi Olibanum )10 g, Moyao (Myrrha)10 g, Zhechong (Eapolyphaga seu Steleophaga )10g, Xuejie ( Resina Draconis )3g, and Gancao (Radix Glycyrrhizae )3 g.
 
(2) Syndrome of collateral disharmony
Main symptoms and signs:
Aching and vague pain in the knee, rigidity and weakness of the knee joint, pale tongue and thready pulse.

Therapeutic methods:
Relaxing tendons and activating collaterals.

Recipe and herbs:
Modified Decoction of Huoxue Shujin. The herbs see the treatment of the same syndrome in external humeral epicondylitis.

External therapy:   
In the early stage, Xiaoyu Zhitong Paste or Sanse Paste may be externally applied; in the late stage, fumigation and bathing on the diseased part with Haitongpi Decoction is taken.
 
Hydro-acupuncture therapy:
Four to six milliliters of 1% procaine plus 25 mg prednisolone are used for injection at the tender points, which can alleviate pain and swelling.

Operative therapy:
For the case of complete rupture of lateral accessory ligament, because there is partial replacement by the iliotibial tract and biceps muscle of thigh and generally no serious dysfunction occurs, the operation may be chosen according to the concrete condition. But, for the case of complete rupture of medial accessory ligament, a neoplasty must be done early.

Functional exercise:
For the case of partial rupture of collateral ligament, exercise on the quadriceps muscle of thigh should be done during the period of fixation. After removal of the fixation, progressive activities of extension and flexion of the knee joint should be practiced.