When is Surgery considered for an MCL injury?
Tibial sided MCL tear/avulsion
MCL may have ‘flipped’ superficial to the hamstring tendons. Preventing the MCL healing to bone. An MCL repair may be required.
Chronic grade 3 MCL injury with functional instability
Patient experiences ongoing instability following an acute injury
Multi-ligamentous knee injury
When the MCL is injured in combination with other internal knee ligaments (i.e ACL/PCL). This represents a complex knee injury.
Repair Vs Reconstruction
A ‘MCL repair’ involves repositioning and re-tensioning the native medical collateral ligament (MCL). In this situation, the ligament itself has sufficient tissue quality to reconstitute knee stability following a repair.
This may be appropriate in the following scenarios:
Tibial sided MCL tear/’avulsion’
The MCL runs from the ‘medial epicondyle’ on the thigh bone (femur) down to the top of the tibia (shin bone). During an MCL injury, it is possible to tear the ligament anywhere along the course of the ligament. When the tear occurs at the insertion onto the tibia (shin bone), the ligament can ‘flip’ itself above the hamstring tendons that also attach to the tibia. This will prevent the MCL from healing adequately, and a MCL ‘Repair’ can be performed to reposition the ligament in the appropriate position.
As part of a multi-ligament knee injury
These represent serious knee injuries, with multiple knee ligaments torn at the same time. While the majority of the other knee ligaments require a ‘Reconstruction’ in this setting, the MCL may be amenable to a direct repair. Each of these cases requires individualised treatment given the complex nature of these injuries.
A MCL repair involves making an incision on the inside of the knee, positioned over the location of the tear. The MCL injury is defined and a decision regarding repair technique is made. These may include the use of ‘suture anchors’ that allow the ligament to be sutured down to its bony attachment. A direct suture repair can also be performed, and any associated injury to the meniscus or knee joint capsule is also addressed. Typically a knee brace is applied to protect the repair. Rehabilitation will depend on the nature of the injury and any associated injuries.
A ‘Reconstruction’ involves using a ‘donor tendon’ to substitute the function of the MCL. This technique is required in the setting where there is poor local tissue for a direct repair, such as in a situation where there has been long term instability of the knee.
Dr. Smith performs MCL reconstructions using hamstring tendons that is harvested from the inside of the knee, through the same incision that is used for the reconstruction itself. The hamstring tendon is fashioned into a graft that will be positioned where the original MCL was. It is very important to get these ‘fixation points’ correct, to ensure that the new ‘ligament’ functions in the same fashion as the original MCL. The graft is then held in position with the use of specialised screws.
Typically a period of crutch use and knee brace is required following the procedure.