MLKI
Multiligament Knee Injuries
Phone +971-2-4446600
Anatomy
Multiligament knee injuries (MLKI) refers to injuries resulting in 2 or more out of the 4 large ligaments complexes of the knee being injured. ACL, PCL, posteromedial complex and posterolateral complex represent the 4 structures and they can be torn in different patterns depending on the injury mechanism. Most common is the combination of ACL and medial complex resulting in increased anterior and rotatory instability. Other combinations are PCL + posterolateral complex and ACL + PCL, and of course the even more severe injuries of 3 or all 4 structures torn.
Knee dislocation is when the lower leg (tibia) and thighbone (femur) due to high energy trauma are displaced though the knee. This almost always forces a multiligament injury to the knee and results in a highly unstable knee. Fractures, nerve injuries and vascular damage are not uncommon during these traumas.
As mentioned, usually MLKI and dislocations are the result of high energy trauma, either severe sports injuries, traffic accidents or high falls. Therefore, these injuries are usually seen at hospitals or trauma centers initially to rule out other even more important injuries to other parts of the body, and to do an initial assessment of the knee injury. Regarding the knee, reduction and casting or bracing is needed to control the position and pain and a full evaluation of vascular, neurological, bony and ligament status is performed. X-rays and MRI are needed as a good clinical examination usually is hard to perform due to the pain, swelling and instability. Furthermore, there is a low threshold for CT-scan and angiography for further evaluation.
X-ray of knee dislocation
Evaluation
Once the initial assessment to rule out more life and limb-threatening injuries is complete, focus can be turned to the ligaments and instability.
These are complex injuries that require examination of all ligaments and possible instabilities, including anterior, posterior, varus, valgus and rotational tests.
Meniscus and cartilage injuries are commonly accompanying such big traumas and can also be evaluated with examination and MRI.
For further testing, stress-X-rays can be used to quantify instabilities and to get as much information as possible before deciding on a treatment plan.
MRI of Multiligament injury with torn ACL, PCL, MCL and PLC
Treatment
These injuries generally require surgery. The knee is too unstable to even do day to day tasks for most people and surgery to increase stability by reconstructing the torn ligaments have shown good results in getting people back to a more active lifestyle which of course is beneficial for overall health.
The surgery is demanding and usually complex, which is why this is to be performed at a knee or sports center with experience in these injuries. Reconstruction of several ligaments in one surgery can take up to several hours and can require allograft (donor) tissue to be used to replace the original ligaments.
During these surgeries, any meniscal tears, cartilage damage or nerve affection is also evaluated and often can be addressed at the same time.
X-ray after surgery. Different fixation techniques can be used for the different reconstructions
Rehabilitation
The day after surgery, a year of physiotherapy and rehabilitation starts. Initially there will be no weightbearing and very little motion in the knee, but within a couple of weeks the motion increases with the exercises and the muscles are activated. After 6-8 weeks the weightbearing can progress and you can come off the crutches and start walking properly. Depending on the severity of the injury and surgery, there are different thresholds to hit during rehabilitation, where muscle strength, range of motion and activity level increases month by month. This is not a fast rehab, focus is on getting the knee as good as possible and that usually takes a year minimum.