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Other lateral knee pain causes:
A lateral ligament sprain is most likely following a direct blow to the inside of the knee. We explain the injury and treatment options available.
As with most ligament tears (sprains) the extent of the damage can be categorized into 3 different grades:
Mild tenderness on the outside of the knee over the ligament. Usually no swelling. When the knee is bent to 30 degrees and force applied to the inside of the knee (stressing the lateral ligament) pain is felt but there is no joint laxity (see knee assessment ).
Significant tenderness on the outside of the knee on the lateral ligament. Some swelling seen over the ligament. When the knee is stressed as for grade 1 symptoms, there is pain and laxity in the joint, although there is a definite end point (the knee cannot be bent sideways completely).
This is a complete tear of the ligament. Pain can vary and may be actually less than a grade 2 sprain. When stressing the knee there is significant joint laxity. The athlete may complain of having a very unstable knee.
The lateral ligament or lateral collateral ligament (LCL) forms a connection between the femur (the thigh bone) and the head of the fibula, which is the outer bone of the lower leg. It is a narrow strong cord of collagen fibres that serves to prevent the outer surfaces of the knee joint from opening or gapping.
The LCL is most commonly injured in sports by a direct impact to the inner surface of the knee joint, such as by a rugby or a football tackle. Injuries of this type are less common than those affecting the medial collateral ligament (MCL) which commonly occur as a result of trauma to the outer surface of the knee joint. In addition, the LCL is not connected to the lateral meniscus and so unlike MCL injuries, they are not normally associated with meniscal tears. However, due to the nature of the injury the anterior cruciate or posterior cruciate ligaments may also become damaged.
The initial aim of a health professional will be to assess the extent of the damage. This can be carried out by applying a force to the inner surface of the knee joint and comparing its laxity to the unaffected knee (varus knee test). In more serious cases an MRI scan and/or X-Ray may be necessary. Depending on the severity of the injury a number of treatment options are presented to the clinician.
In grade 1 & 2 tears, conservative methods of treatment are usually preferred. These may need to be be carried out for up to 8 weeks and may include:
In grade 3 sprains (ruptures), particularly when other structures such as the ACL or PCL are damaged, surgery may be needed to prevent future instability. This may involve suturing (stitching) the torn ends of the LCL or reconstructing the ligament with a part of a tendon e.g. hamstrings tendon. Recovery from these injuries is a lot slower than conservative methods and it may be a number of months before the athlete is able to return to sports.