Quadriceps Strains
To decrease risk of quad strains… strengthen the quadricep muscles!
Vastus Lateralis is found on the most lateral (outer) aspect of the thigh. It is the largest, and typically strongest, muscle of the quadriceps group. Strength imbalances between vastus lateralis and the other quadricep muscles can explain abnormalities in patello-femoral tracking. This can include patellar subluxations / dislocations as vastus lateralis typically pulls the patella in a lateral direction with greater force than is produced by muscles that pull in a medial (inside) direction.
Vastus Medialis is the most medially located, along the inside of the thigh.
Rectus Femoris is located centrally between vastus medialis and vastus lateralis. Rectus femoris is the most commonly strained as it is the only quadriceps muscle that crosses both the knee and hip joints. At the hip, rectus femoris causes flexion (bending at the hip bringing the thigh closer to the chest). At the knee, rectus femoris causes extension (straightening out the knee).
Vastus Intermedius is located on the anterolateral (front, outside) portion of the thigh. Vastus intermedius is not pictured as it sits deep beneath the other quadriceps muscles.
All four quadriceps muscles insert to the quadriceps tendon. The quadriceps tendon surrounds the patella (or ‘knee cap’) and inserts to the tibial tuberosity - the bony prominence on the front, top aspect of the shin.
A Muscle Strain is the excessive stretching of muscle fibers, typically classified according to three grades of severity.
Grade I strains involve disruption to very few muscle fibers, resulting in minimal / no loss of strength.
Grade II involves damage to less than 3⁄4 of total muscle fibers and moderate loss of strength. Grade III involves damage to more than 3⁄4 total muscle fibers and significant / complete loss of strength.
Common Symptoms of muscle strains include localized pain, swelling, bruising, loss of strength, or decreased range of motion (at the knee and / or hip) which may produce an antalgic gait (walking with a limp).
In the Quadriceps, this Injury Typically Occurs when performing non-contact, explosive movements such as sprinting, jumping, or kicking. The rectus femoris muscle has the highest risk of muscle strains because forceful eccentric (lengthening) contractions can occur when the muscle is stretched at both the hip and knee joints.
Contrastingly, muscle strains that occur in vastus medialis or vastus lateralis are typically the result of a direct blow from a player or object.
Another Common Mechanism in which the quadriceps can be strained is if the muscle is overstretched.
To Decrease the Risk of experiencing a quad strain it is recommended to strengthen the quadriceps muscles. This is best achieved through resistance training exercises, specifically eccentric (lengthening) muscle contractions.
Recommendations for Healing vary based on phases of injury healing:
In the Acute (Immediate) Healing Phase it is recommended to apply ice and compression to the muscle for 20 minutes (allowing 30-60 minutes between applications). Resting with the knee in a flexed (bent) position for the first 24 hours can help reduce hematoma (bruise) formation. This is also the stage when you should visit your physiotherapist.
Specific Exercises for this phase include:
Prone (lying on stomach) quad stretch
Isometric quad contractions (towel under knee)
During the Sub-Acute Healing Phase stretching and strengthening are recommended to regain pre-injury range of motion and strength.
Specific Exercises for this phase include:
Squats
Step ups (with slow lowering)
VMO biased leg raises (toes turned outwards)
Finally, Functional / Return to Activity progressions are made exercises in order to advance strength, improve proprioception, and facilitate pain-free activity.
Specific Exercises for this phase include:
Box jumps
Skaters
Modified return to activity