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​​Injuries to the knee:​

Medial collateral ligament (MCL) injuries in football

Knee injuries can affect players of all ages and a frequently occurring injury is a sprain of the medial collateral ligament of the knee; usually referred to as the MCL (Le Gall et al, 2006)...

Football / Soccer carries a high risk of knee injuries due to the emphasis placed on the lower limb as part of the game (Dick et al, 2007).  The greater percentage of these injuries are to the lower limb; particularly to the knees and ankles, as opposed to the upper limb (Price et al, 2004). 

Anatomically, ligaments are strong bands of fibrous connective tissue that join bone to bone; with the MCL joining the lower aspect of the femur to the tibia.  The MCL limits excess movement of the knee in an inwards, or medial direction. 

Basic anatomy and injury mechanics

The MCL provides the primary stability to the knee on the inside part of the leg (Marchant et al, 2011), or medial aspect in medical terms. It is easily injured in the tackle, hence MCL sprains are one of the most common injuries in the game. 

Previous research has shown that the MCL is the most commonly injured structured in the knee (Wijdicks et al, 2010).  MCL injuries usually result in an average 6 – 8 weeks absence from sport based on the recovery time for a typical Grade 2 ligamentous sprain.

MCL injuries have been shown to occur in football as the result of an excess valgus force usually as a result of making direct contact with an opponent.  A valgus force is the description given to a movement that results in the medial aspect of the knee joint being forced inwardly; leading to an increased stress being placed on the structures therein. 

MCL injuries can occur in isolation or in combination with simultaneous injuries to other structures of the knee. 

These can often accompany injuries to the Anterior Cruciate Ligament (ACL), the medial meniscus, or occur as a combination of both involving all three structures.  When the MCL is injured in conjunction with the ACL and medial meniscus, this is known as O’Donoghue’s Triad. 

Although O’Donoghue’s Triad occurs in football aka soccer, the most frequent incidences of this are normally recorded in American Football.  Affecting three of the important structures in the knee, this is a complex injury that results in a lengthy absence from sport and almost always involves surgery; usually to the ACL.

Isolated MCL injuries can occur in sport and these are common; affecting players of all ages. As described, the most frequent cause of MCL injury in football is through direct contact with an opponent.  A typical ‘block tackle’ made with the inside of the foot is normally the classic injury mechanism for an MCL sprain. 

If the force of the impact is strong enough, the shin will be forced outwards in a lateral direction, and the medial aspect of the knee will come under excessive stress.  The MCL will then become stretched or torn. 

Another common mechanism of MCL injury occurs when being tackled from the side.  If the blow from the tackle is received on the outside of the knee, the limb will give way and the knee will be forced inwards into a valgus position.  This type of force will stress the medial side of the joint even though the actual blow is taken on the outer aspect of the leg. 

It is the resultant force on the stabilising structures acting on the opposite part of the joint that will lead to injury; with the knee ligaments on the medial side being stretched or torn as the joint effectively opens.

So MCL injuries normally occur either from an external force such as in tackle by an opponent which forces the joint to ‘over-stretch’.  However, another scenario is when the MCL is injured through intrinsic mechanisms when a twisting movement occurs with the foot fixed.

In these cases, a player’s studs will often stick in the ground thus leading to an increased force straining the ligaments and resulting in a tear.

As a strong, thick, flat band of connective tissue, when the MCL tears, it tears in accordance with the grading system mentioned in previous discussions; of which a Grade 1 injury is minor sprain with damage limited to only a few fibres of the ligament. 

A Grade 2 injury involves considerable more than a few ligamentous fibres and is considered to be a ‘moderate’ injury; while a Grade 3 tear is a complete rupture. 

It has to be said, though, that there is an emerging school of thought which suggests that these ‘traditional’ classifications are now less relevant in modern-day sports medicine and should be replaced by a more accurate system (Mueller-Wohlfart et al, 2012).

Discussing a Grade 2 strain that in reality just exceeds a minor Grade 1 injury leaves ample scope for variables in its interpretation. 

Medical management of MCL injuries

In MCL injuries, the most tender area is localised to the inside aspect of the knee, corresponding with the actual joint-line where the ligament crosses the junction where the medial meniscus is attached.  If the injury is severe enough, this area might be warm to the touch. 

It will certainly be painful; so digging your fingers in and asking ‘does this hurt?’ is not a good idea!

The mechanics of the injury will clearly indicate an MCL sprain anyway; but the important part now is to assess how much damage has been done to the knee and whether there are any other structures involved. 

Attempting to take any body weight through the joint will only result in feeling that the knee will collapse.  Any sideward movement such as applying a valgus stress will increase pain and also potentially worsen the injury during the acute stage.

MCL injuries should be seen by a doctor / physician or physiotherapist / physical therapist who may initiate deeper investigations if appropriate to rule out associated injuries to other structures such as to the meniscus, cruciate ligaments, accompanying soft-tissues or even bony injury. 

Correct management in the initial stages of injury sets the tone for the whole rehab period.   A hinged knee brace and crutches is usually the order of the day immediately following knee ligamentous injuries.  

This will assist with early management, reduction of pain, and to support the injured structure(s).   However, the main purpose of the hinged brace is to protect against any sideways movements until the damaged tissues start to heal. 

The most effective method of treatment is to partially immobilise the knee in a hinged brace fitted with metal stabilisers on either side to prevent medial and lateral movement as soon as possible after the injury has occurred. 

Hinged braces are easily sourced on most sports medical suppliers’ websites but will normally be routinely issued at the time of the initial appointment with a clinician.  If we happen to be dealing with an unstable knee immediately post-injury then it’s imperative that the player is seen by a physician with the minimum delay.

The importance of using a hinged brace cannot be over-emphasised.  Ligamentous tissues are at their most vulnerable in the immediate period following the injury; and if left unsupported will heal in a less than ideal position. 

To prevent acute MCL sprains leading to instability, early injury management should focus on immobilising the knee in such a way that the ligament is under minimal stress.

Since ligamentous structures need to be tight and strong in order to support the joint they are meant to be protecting; if left unchecked these will stretch and heal in a looser position than is required, leading to an unstable or wobbly knee in the future. 

This happens because healing tissue is like soft plaster; and the more it is disturbed before it is allowed to set properly, the less strong the end result will be.  This can mean that a greater risk of incomplete healing could take place, potentially leading to recurrence or chronic instability in the future.

Although immobilisation techniques may vary (Sommerfeldt et al, 2015) use of a hinged brace will allow for the safe movements of bending and straightening the knee to take place whilst stabilising the inwards (valgus) movements that stress the MCL. 

From an rehabilitation aspect it’s vitally important to keep the knee moving through the ranges not directly affected by the MCL in order not to lose any natural movements that are unaffected by the injury. 

Gentle bending and straightening won’t place much stress on the collateral ligaments anyway, since the movements to avoid are those in a sideward direction. 

However, it is important to remember that if swelling is present then this can restrict available movement ranges.

Once the healing process has begun and associated injuries to the meniscus and ACL etc. have been excluded, physical therapy involving strengthening exercises for the knee as a whole can then be initiated. 

Discussion:  Surgical v non-operative management of MCL injuries

There has been a constant debate throughout the years over the benefits of surgical v non-operative management for isolated MCL injuries.  

Instability of the knee arising from an MCL sprain is often the biggest risk and occurs when the ligaments that stabilise the joint have been stretched or torn; and are no longer able to support the joint. 

Over time, chronic laxity develops and the knee becomes inherently unstable if left untreated.  Such laxity can lead to the knee feeling “loose and wobbly”; often with an accompanying sensation that the knee is going to “give way”. 

If severe enough, initial injuries to the MCL can also result in instability if left unaddressed in cases where the injury is classified as either a Grade 3 sprain or a higher-end Grade 2 injury. 

In these cases, many surgeons believe that the best results in MCL rehabilitation are gained through surgical reconstruction of the ligament.  Where repeated injuries have led to chronic laxity over time, several consultants prefer to follow the operative route while others disagree.

Phisitkul et al (2006) discussed the potential for both options and concluded that although surgical treatment may have a role to play in many cases, most medial-sided knee injuries are better treated non-operatively; particularly in cases of minor Grade 1 and lower Grade 2 ligamentous sprains.

The general feeling, therefore, is that rest and controlled activity during the early period immediately post-injury is the method of treatment favoured by most orthopaedic surgeons and sports medicine professionals. 

In many cases, though, it is the immediate treatment and management of injury that leads to a successful rehabilitation period and ultimately a return to play.  This will vary depending of the severity and nature of the injury.

In football though it’s not just about the medical management of injuries, there’s the components of the game to consider also.  Returning to play after a lengthy period as a result of an injury needs to be managed correctly in addition to following the medical advice given by the physician or therapist. 

Return to the team is dependent on the strength of the injured knee matching that of the non-injured side, ensuring that the injured knee has the same flexibility as the non-injured side, and finally is pain-free without showing any adverse reaction to physical exercise.

Of course it’s also essential to address the football / soccer aspects of the recovery process.  Players coming back from injury need to be able to complete all the things required during the course of the game such as running, twisting, turning, kicking, jumping and sprinting etc., before being considered for a return to the team. 

Attempting to go straight back into the team without first of all ensuring that your player can meet all the requirements of the game is only asking for trouble and is likely to lead to repeat or recurrent injury.


Dick R, Putukian M, Agel J, Evans TA, Marshall SW (2007).  Descriptive epidemiology of collegiate women’s soccer injuries: National Collegiate Athletic Association Injury Surveillance System, 1988 – 1989 through 2002 – 2003.  Journal of Athletic Training.  Vol. 42 (2); 278 – 285.

Le Gall F, Carling C, Reilly T, Vandewalle H, Church J, Rochcongar P (2006).  Incidence of injuries in elite French youth soccer players: a 10-season study.  American Journal of Sports Medicine.  Vol. 34 (6); 928 – 938.

Marchant MH Jnr, Tibor LM, Sekiya JK, Hardaker WT Jnr, Garrett WE Jnr, Taylor DC (2011).  Management of medial-sided knee injuries, part 1; medial collateral ligament.  American Journal of Sports Medicine.  Vol.39 (5); 1102 – 111.

Mueller-Wohlfahrt H-W, Haensel L, Mithoefer K, Ekstand J, English B, McNally S, Orchard J, Niek van Dijk N, Kerkhoffs GM, Schamasch P, Blottner D, Swaerd L, Goedhart E, Ueblacker P (2013).  Terminology and classification of muscle injuries in sport: the Munich consensus statement.  British Journal of Sports Medicine.  Vol. 47; 342 - 350​

Price RJ, Hawkins RD, Hulse MA, Hodson A (2004).  An audit of injuries in Academy youth football.  British Journal of Sports Medicine.  Vol. 38; 466 – 471.

Phisitkul P, James L, Wolfe BR, Amendola A (2006).  MCL injuries of the knee: Current concepts review.  Iowa Orthopaedic Journal.  Vol. 26; 77 – 90.

Sommerfeldt M, Bouliane M, Otto D, Rowe BH, Beaupre L (2015).  The use of early immobilisation in the management of soft-tissue injuries of the knee: results of a survey of emergency physicians, sports medicine physicians, and orthopaedic surgeons.   Canadian Journal of Surgery.  Vol. 58 (1); 48 – 53. 

Wijdicks CA, Griffith CJ, Johansen S, Engebretsen L, LaPrade RF (2010).  Injuries to the medial collateral ligament and associated structures of the knee.  Journal of Bone and Joint Surgery of America.  Vol. 92 (5); 1266 – 1280.

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​Explaining injuries in a way that's easy to understand!!