Medial collateral ligament (MCL) sprain

What it is

The MCL is a broad band on the inner side of the knee that stops the knee being pushed inward. Injuries are graded from a stretch, through a partial tear, to a complete tear. Unlike the ACL it sits outside the joint and has a good blood supply, so the great majority heal without surgery. It is one of the better outcomes among serious-feeling knee injuries, but the grade drives the timeline and a grade three is not a two-week problem.

How volleyball causes it

The signature volleyball mechanism is landing under the net on somebody else's foot. The foot rolls or gets stuck, the body keeps travelling, the knee falls inward and the inside of the joint is forced open. The non-contact version is a single-leg block landing or a slide approach plant where the knee caves inward under a body that is moving sideways. Occasionally it is a direct blow to the outside of the knee, usually from a teammate diving through the same patch of court. Beach players are less exposed but a foot buried in soft sand while the body keeps going produces exactly the same forces.

BlockingAttackingDefense

What it feels like

• Pain along a specific band on the inside of the knee that is tender when you press along it
• It hurts when the knee is pushed inward, so sidestepping towards the injured side is uncomfortable
• Swelling that is localised to the inside of the knee rather than filling the whole joint
• A feeling that the inside of the knee opens or gives when you plant and turn
• Stiff and sore at full straightening and full bending for the first few days
• In the first day or two, walking with the leg slightly bent and turned out to protect it

Stop and get it seen if

• The knee feels loose in more than one direction, gives way, or there was a pop with the whole joint swelling within a couple of hours. That suggests the ACL or several ligaments are involved and needs prompt assessment.
• Cannot take weight at all, or there is bony tenderness at the kneecap, top of the shin, or the end of the thigh bone. In players who are still growing, the growth plate at the end of the thigh bone can fail instead of the ligament, and that must not be missed.
• Numbness, pins and needles, or a cold or pale foot on that side.
• The inside of the knee becomes hot, red and increasingly painful with fever or feeling unwell.

What recovery usually looks like

Stages, not a schedule. Everyone moves through these at their own pace, and the ranges are wide because real recoveries are.

1. 1. Protect and settle

   3 days to 2 weeks

   Protect the healing ligament, control swelling, and restore normal walking and straightening. Higher grades are often braced for this period.

   • Walking without a limp
   • Localised swelling settling
   • Full straightening restored
   • Pressing along the ligament is uncomfortable rather than exquisite

2. 2. Load the ligament and rebuild strength

   2 to 6 weeks

   Restore full range and rebuild quadriceps, hamstring and hip strength, including control of sideways movement.

   • Full bending and straightening compared with the other knee
   • Shuffling and lateral movement comfortable at moderate speed
   • Single-leg standing steady
   • A gentle inward stress on the knee no longer produces sharp pain

3. 3. Return to landing and lateral play

   a further 1 to 4 weeks, which puts a grade one at roughly 1 to 3 weeks from injury in total, a grade two at 3 to 6 weeks, and a complete tear at 6 to 12 weeks or more

Ready to play again when

• No tenderness along the ligament and no pain when the knee is stressed inward
• Full range in both directions compared with the other knee
• Can shuffle, block-step and cut at full speed without inside knee pain or a sense of the joint opening
• Can land a block jump off balance and recover without the knee caving

Keeping it from coming back

This is ordinary training, so unlike the rest of this page it does tell you what to do.

• Hip abductor and glute strength: banded lateral walks, side-lying abduction, hip thrusts. A hip that holds the thigh keeps the knee from falling inward on landing.
• Copenhagen adductor holds, so the inside of the thigh contributes to controlling the knee rather than being the weak link.
• Landing drills with explicit feedback on knee position, especially single-leg block landings, which is where the non-contact version happens.
• Centre line habits. Drill blockers to land back on their own side and coach hitters and blockers to be aware of feet under the net, because most volleyball MCL sprains involve somebody else's foot.
• Ankle strength and single-leg balance work, including landing on one foot and holding it. A rolling ankle sends the knee inward, and the ligament pays for it.