The function of the knee-joint depends upon the integrity of the medial, lateral, anterior cruciate and posterior cruciate ligaments. Injuries of the ligaments often present a complicated picture. Considerable skill may be required to understand and treat the problems. Lesions of the ligaments may be present in the form of a sprain or rupture. Once the rupture is diagnosed, this should be treated by surgery as an early procedure. Delay in performing the operation may lead to further instability of the joint, atrophy of the quadriceps and degenerative changes of the knee. The joint may fail to recover completely when delayed reconstructive surgery is undertaken. The surgeons use ortho implants and instruments to perform the surgery.
INJURIES OF THE MEDIAL LIGAMENT
MECHANISM OF INJURY
Severe violence on the outer aspect of the knee-joint produces a lesion of the medial ligament. This usually happens in athletic activities in an automobile accident.
NATURE OF LESION
The lesion can be of varying severity. This may be in the form of
- Incomplete rupture
- Complete rupture of the superficial and deep fibers of the medial ligament
There may be rupture of the medial meniscus and anterior cruciate ligament along with the lesion of medial ligament.
The site of rupture of the medial ligament: Rupture can take place at the upper femoral or lower tibial attachment.
Sometimes there may be avulsion of the bone segment attached to the ligament.
Clinical features: History of the nature of the injury is important. The patient experiences the feeling of the joint giving way during walking. There are pain and tenderness over the medial aspect of the knee-joint along with swelling due to effusion.
Test of the rupture of the medial ligament: Valgus strain is applied on the knee-joint by the examiner with one hand above the knee and the other below. Rupture will elicit instability on the medial side. This test can sometimes be performed under general anaesthesia.
Test for cruciate ligament: The patient’s knee-joint is flexed to 90⁰. The leg is grasped with both hands. The foot is fixed on the table which can be done by sitting on the toes of the patient. An attempt is made to glide the upper end of the tibia in the anterior and posterior directions over the lower end of the femur. The mobility is compared with the normal joint.
X-ray diagnosis: X-ray may not show any abnormality. There may be some soft tissue swelling or any avulsed bone segment may be seen when this is present.
X-ray testing of instability: this technique can be valuable in detecting the type rupture. This is done preferably under general anaesthesia when pain is present. X-ray of the knee is taken after applying valgus strain to the joint. The view is compared with the normal knee and the amount of separation of the joint surfaces is observed. Surgery is performed when the instability of the joint is more than 10⁰ ; the otherwise conservative regime is advocated.
The patient can be treated in two ways which depend on the type of lesion:
- Conservative treatment: For sprain and partial rupture.
- Operative treatment: Operation is done for isolated complete rupture of the medial ligament and for associated rupture of the cruciate ligament.
Following measures are undertaken while doing the conservative measures.
- Aspirate the joint: Under local anaesthesia the blood from the knee-joint is aspirated.
- Compression bandage: Lots of orthopedic wool is wrapped is wrapped round the joint and compression bandage is applied. Siora Surgical is orthopedic implants importer across the globe.
- Dorsal splint: A dorsal splint extending from the groin up above the malleoli is applied and maintained till the swelling subsides. This usually takes a period of 4-5 days.
- Plaster cylinder immobilization: Plaster cylinder is then given when the swelling subsides. The patient is advised quadriceps exercise and straight leg raising and allowed weight bearing.
- Post immobilization period: The plaster cylinder is usually removed after a period of 6-10 weeks. Vigorous knee exercise is advised after removal of the plaster.
Operative management: Operation is performed for complete rupture of the medial ligament. The management of the lesions of anterior cruciate ligament is described in the corresponding chapter. The area is exposed and the repair is done in accordance with the nature of injury. Firstly the deeper layer of the medial ligament is sutured, then the superficial layer of the ligament is repaired by non-absorbable suture material.