The function of the collateral ligaments of the knee is to stabilise the knee from varus / valgus forces. Consists of a Medial & Lateral ligament.
1. Medial Collateral [ MCL]
Excessive Valgus forces to partially flexed knee. Direction of force lateral to medial. Can be contact or non-contact.
2. Lateral Collateral Ligament [LCL]:
Usually a severe, high energy, direct Varus forces. Direction of force, medial to lateral. Less common than MCL strains.
Differential diagnosis?
Assessing Severity of Strain Graded
Grade I : Mild , [1st degree].
Local tenderness over MCL and femoral condyle or tibial plateau, minimal swelling,
Testing: valgus stress at 30° flexion, pain but no laxity
Grade II : Moderate,[ 2nd degree]
Marked tenderness, sometimes localized swelling
Testing: valgus stress at 30°flexion, pain, some laxity [typically <5mm], but distinct end point.
Ligament integrity is compromised but intact throughout its length.
Grade III: Complete, [3rd degree] ,
Instability present. Patient complains of “wobbly knee”.
Pain variable, often not as painful as Grade II
Ligament tenderness
Testing : Gross laxity. Lacks distinct end feel.
Often associated ACL tear, but rarely meniscus.
References
Image from OpenI – Licensed by CC
Image from OpenI – Licensed by CC
Treatment (see tables)
Rehabilitation programme Grade I mild MCLStrains
| Phase | Phase Goals | Time Post Injury | Physiotherapy Treatment | Exercise Programme | Functional / Sport Related Activity |
| 1: | Control swelling Knee flexion to 100°+ Allow +20 Extension 4/5 Quads strength 4+/5 Hamstring strength | 0 – 1 Weeks | Cryotherapy Electrotherapy Compression Manual Therapy Gait Re-education Patient education | Gentle ROM (flexion) Quads / VMO setting Supported bilateral calf raises Hip abduction/ extension Hamstring (pulleys) Gait re-ed drills | Progress to FWB Normalize Gait |
| 2: | Eliminate swelling Full Flexion ROM 4+/5 Quads strength 5/5 Hamstring strength Return to light jogging | 1 – 2 Weeks | Cryotherapy Electrotherapy Compression Manual Therapy Gait Re-education Exercise modification & supervision | ROM drills Quads / VMO setting Mini squats & Lunges Leg press ( dbl then single) Step –ups Bridges (dbl then single) Hip abd/ extension ( theraband) Gait re-ed drills | Straight line jogging Swimming (light kick) Road Bike : with hinged knee brace |
| 3: | Full ROM Full Strength Full squat Dynamic proprioception Return to running Restricted sport specific drills | 2 – 4 Weeks | Manual Therapy Exercise/ activity modification & supervision | As above. Increase difficulty [ reps weights] Jump / land skills Agility drills | Progressive running Swimming Road Bike Sport specific skills |
| 4: | Full, strength, ROM and endurance Return to sport specific drills & restricted training/ match play | 3 – 6 Weeks | As above | High level sport –specific strengthening required | Return to sport specific drills & restricted training/ match play with hinged brace |
Rehabilitation programme Grades II – III moderate to severe MCLStrains
| Phase | Phase Goals | Time Post Injury | Physiotherapy Treatment | Exercise Programme | Functional / Sport Related Activity |
| 1: | Control swelling Knee flexion to 90°+ Allow +30 Extension 4/5 Quads strength 4+/5 Hamstring strength | 0 – 4 Weeks | Limited motion brace (0-30°) Cryotherapy Electrotherapy Compression Manual Therapy Gait Re-education Patient education | Exercises done in brace Gentle ROM (flexion) Extension ROM to 30° Quads / VMO setting Supported bilateral calf raises Hip abduction/ extension Hamstring (pulleys) Gait drills | Initially NWB/ PWB Progress to FWB Walking / normal Gait |
| 2: | FWB Eliminate swelling Full ROM 4+/5 Quads strength 5/5 Hamstring strength Return to light jogging | 4 – 6 Weeks | Removal of Knee brace Cryotherapy Electrotherapy Compression Manual Therapy Gait Re-education Exercise modification & supervision | ROM drills Quads / VMO setting Mini squats & Lunges Leg press ( dbl then single) Step –ups Bridges (dbl then single) Hip abd/ extension ( theraband) Single legged calf raises Balance & proprioceptive drills | Swimming (light kick) Road Bike Walking |
| 3: | Full ROM Full Strength Full squat Dynamic proprioception Return to light jogging Return to running & Restricted sport specific drills | 8 – 10 Weeks | Manual Therapy Exercise/ activity modification & supervision | As above. Increase difficulty [ reps weights] Jump / land skills Agility drills | Straight line jogging with hinged knee brace [ no earlier than 6 wks] Running Swimming Road Bike Sport specific drills, ie fwd back side running, kicking |
| 4: | Full, strength, ROM and endurance Return to sport specific drills & restricted training/ match play | 8 – 10 Weeks | As above | High level sport –specific strengthening required | Return to sport specific drills & restricted training/ match play with hinged brace |
