Medial Collateral Ligament (MCL) Injury
Other popular names
- MCL Tear
Who does it affect?
All people, but particularly those engaged in sporting activities.
Why does it happen?
The main restraining ligament on the inside of the knee is the Medial Collateral Ligament (MCL). This is a ligament that is frequently injured when the lower leg is forcibly deviated laterally (away from the body).
Symptoms
Following an injury, pain is normally experienced over the medial aspect of the knee. It is usually associated with some swelling and there is tenderness on examination.
Diagnosis
An MRI scan is often used to confirm the clinical diagnosis and differentiate it from other injuries such as a meniscal tear and identify whether any other structures have been injured as the medial meniscus and ACL are often also inured at the same time as the MCL.
Non-surgical treatment
Fortunately, most MCL injuries will heal well and there is usually no need for surgical treatment. For mild sprains, rest, analgesia and physiotherapy is usually sufficient. For more severe sprains, the knee sometimes needs to be supported in a brace to allow the ligament to heal in a good position.
The healing process following an MCL injury takes place over a period of 6 to 12 weeks depending on the severity of the injury.
Occasionally, after the ligament has healed, there can be significant laxity that can give instability symptoms similar to those that occur after an anterior cruciate ligament injury and these might occasionally require surgery.
In addition, the MCL is sometimes repaired or reconstructed acutely in the complex multi-ligament knee injury.
Surgical treatment
MCL reconstruction surgery involves a general or spinal anaesthetic as a day case or overnight stay.
The procedure is usually performed arthroscopically (through keyhole surgery) and is aimed at replacing the deficient MCL with a graft ligament to stabilise the knee.
If reconstruction is necessary then it is reconstructed along the same principles as with an ACL Reconstruction using the medial hamstring tendons with an arthroscopically assisted technique.
Post-surgery rehabilitation
Most patients are able to return home on the same day as surgery or the following day. All patients will need someone to take them home and be with them on the night following surgery.
The anaesthetic will wear off after approximately 6 hours. Simple analgesia (pain killers) usually controls the pain and should be started before the anaesthetic has worn off.
Patients need to use crutches for the first 2 weeks following surgery although they can fully weight-bear - the crutches are mainly to prevent falls until good muscle control has been regained to the leg.
Dressings
The large bandage around the knee is normally removed 24-48 hours after surgery and a tubigrip to supply gentle compression to reduce post-operative swelling.
The non-stick sterile dressings on the wounds are replaced with clean waterproof dressings . The larger incision over the site of the hamstring tendon harvest site is closed using dissolving stitches and the paper butterfly sutures overlying this can be peeled away easily after 10 days.
Return to normal routine
Bathing and showering
The wounds should be kept clean and dry until the wound has sealed. Showering is fine and the waterproof dressings can be changed afterwards. Bathing is best avoided until the wounds are sealed, typically 10 days after surgery.
In summary, whilst the wounds are wet - keep them dry and when the wounds are dry, you can get them wet!
Rehabilitation
Surgery is followed by a prolonged course of physiotherapy. This requires a commitment to undertake this rehabilitation in order to achieve the best possible result (at least half an hour per day for 6 months). It is vitally important to stay within the post-operative activity restrictions an physiotherapy guidelines to avoid damaging stretching your reconstructed ligament.
Return to work
The timing of your return to work depends on the type of work and your access, however, the following is a general guide:
- Desk work: as soon as pain allows and you can travel easily to and from work (2 weeks)
- Light duties: if the job allows partial use of crutches or limited walking (2-5 weeks). If the job involves standing for prolonged walking, bending, lifting, stairs but no squatting (7-8 weeks)
- Heavy duties: full squatting, heavy lifting, digging, in and out of heavy machinery, ladder work etc (3-4 months)
Driving
When you can walk without crutches or a limp and be in control of your vehicle (about 4-6 weeks).
Risks
MCL reconstruction is an extremely safe and reliable operation. However there is a risk of problems or complications with any surgery.
These risks include:
- Infection, which can occur with any operation. Special precautions are taken during surgery to diminish this risk, however, the risk still exists but there is <1% chance of developing a serious infection (major wound breakdown, septic arthritis or osteomyelitis).
- Injury to blood vessels or nerves. Major injuries to these structures are extremely rare, although it is not uncommon to develop some reduced sensation around the shin wound, this rarely causes a problem
- Deep vein thrombosis / pulmonary embolus (DVT/PE) (blood clots) can also occur as with all operations (<0.2% of a serious clot). This does pose a definite but miniscule risk to life (<1:10000).
- Stiffness of the knee joint after MCL surgery can result from a number of causes. Fortunately these are rare. Some individuals are predisposed to form excessive and thick scar tissue. This is treated by surgical excision of the scar tissue (0.5%)
- Re-rupture can happen if excessive force occurs to the knee in the early post-operative period (performing the wrong activities too early). Rupture can also occur at a later stage by another injury (4-5%). If this occurs then the options remain the same - that is to either live around ongoing instability symptoms or to undergo revision MCL reconstruction.
All these risks are uncommon and in total, the chance of you or your knee being worse off in the long term is about or less than 1%.