Ligaments are strong, flexible, fibrous structures that connect bones to other bones. Articular ligaments pass inside or around joints and provide strength and stability. Ligaments are made from collagen connective tissue. In some people the connective tissue may stretch more than others leading to joint laxity and the term ‘double-jointed’ being used. Extreme laxity may lead to problems with joint dislocations or pain symptoms.
Ligaments may become damaged when excessive forces pass around or across the joint. The ligament may tear in half, intra-substance tear, or be pulled from their attachments to bone (avulsions). Most commonly this type of injury occurs on the sports field but may be caused by any significant trauma. The ligament tear or avulsion may be partial or complete leading to varying levels of symptoms and joint laxity.
Ligament tears tend to be acutely painful and often a ‘snap or 'pop’ may be heard or felt as the ligament breaks. Usually the tear is associated with significant swelling and bruising as blood vessels often run within the ligament. Usually the swelling leads to stiffness and a restriction in the range of joint movement.
As the swelling within the joint subsides and the range of movement returns symptoms of instability may develop. This is often described as the joint feeling vulnerable during particular activities or may present as ‘giving-way’ and collapse of the joint.
The anterior cruciate ligament (ACL) is a major stabilising ligament in the centre of the knee. This ligament can be ruptured when excessive force passes through the joint and is usually associated with a twisting or ‘pivoting’ injury. Sports more commonly associated with ACL injury include skiing, football, rugby and netball. Often the injury occurs in a non-contact or ‘off the ball’ situation.
A ‘popping’ sensation is often described as this injury occurs followed by sudden pain and rapid swelling. The athlete is usually unable to play on.
Following ACL injury it often takes several weeks for the swelling to settle and for the range of movement to return. Pain in the knee improves as the inflammation subsides.
An ACL rupture is a very significant injury to the knee and is often associated with other internal derangement including meniscal tears, collateral ligament damage and damage to the chondral surfaces. Active patients often develop ongoing instability problems and giving-way symptoms that may lead to further damage inside the joint.
Early referral to a knee specialist is recommended so that the knee can be fully assessed and appropriate treatment commenced.
The correct management of ACL injuries varies and should be tailored for every patient. Treatment strategies depend on the age of the patient, activity levels, medical health, sporting and career aspirations as well as any concurrent injury within the knee.
Some patients are able to function very well with a deficient ACL ligament and can gain a ‘functionally stable’ knee with strengthening and physiotherapy exercises. ACL reconstruction procedures may be indicated in more active people and higher level athletes who wish to return to sporting activities. Ongoing instability symptoms following ACL injury are generally an indication for surgical ACL reconstruction.
The collateral ligaments run on either side of the knee and prevent side-to-side instability. Occasionally, these ligaments may become injured – either following a direct blow to one side of the knee or during a twisting type injury. Partial or incomplete tears to the collateral ligaments, particularly medially or inside part, are relatively common. The knee often becomes acutely painful and stiff with pain localised to the side of the joint.
Often these injuries can be managed with the help of one of our highly experienced physiotherapists to help regain movement and function. With more severe or complete collateral ligament tears a knee brace may need to be worn for several weeks. Occasionally surgery may be needed to repair or reconstruct a badly torn collateral ligament.
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