Knee Common Pathologies Flashcards
Common pathologies affecting the knee
ACL Injury
Approximately 75% occur with little to no contact.
Most common mechanism is some form of change in force with a planted foot
Contribute to significant time-loss from sport due to surgery
Females are at increased ACL injury risk due to weaker hamstrings.
Can occur in isolation or alongside the injury of other structures.
ACL Injury Continued…
Immediately following MOI: large amount of swelling likely. Patient may report hearing a pop and feeling like the knee ‘went out of place’.
Knee is likely to feel unstable in the first few days/weeks.
If ACL injury suspected, important get MRI; while waiting, place patient in brace.
PCL Injury
Posterior Cruciate Ligament: second cruciate ligament in the knee. Injury is a lot more uncommon than ACL; usually occurs alongside posterolateral corner or other ligamentous injuries.
Mechanism is most commonly a direct blow to the anterior surface of the tibia with knee in a flexed position
PCL Injury Continued…
Isolated PCL injuries present more subtly than ACL; patient may report non-localised posterior knee pain, some swelling and stiffness.
Deep knee flexion likely exacerbates symptoms. May find some muscle guarding or compensatory movements.
MRI gold standard imaging to diagnose
PLC Injury
16% of knee ligament injuries.
PLC made up of 4 static stabilisers:
1. Lateral Collateral Ligament (LCL)
2. Popliteus Tendon: (PLT)
3. Popliteofibular Ligament (PFL)
4. Lateral Gastrocnemius Tendon
Mechanism of injury is a posterolateral directed force on the anteromedial surface of the tibia, hyperextension or excessive external rotation when the knee is partially flexed.
PLC Injury Continued…
Usually occur with other knee injuries. Most frequent symptoms: pain over the posterolateral aspect of the knee, instability when walking on uneven ground, instability near extension, swelling, foot drop, posterolateral rotary instability.
MRI should be conducted when damage is suspected.
MCL Injury
Main stabiliser on medial aspect of the knee. One of the most frequently injured knee structures.
Mechanism is usually a rapid change of direction/speed or direct trauma/blow to lateral aspect of knee; excessive knee valgus. This causes damage or complete rupture of MCL
MCL Injury Continued…
In more traumatic mechanisms, damage to other structures can occur; thorough assessment important.
Patient will often describe ‘knee giving way’ sensation, may hear/feel a pop.
Injuries to MCL usually cause swelling due to blood supply at location around MCL and will likely be painful around proximal attachment.
Clinical assessment reliable method of diagnosis. MRI used when multi-ligament injury suspected.
LCL Injury
Rarely occur in isolation. Not well researched regarding management of isolated LCL injuries.
Mechanism of injury: blow to medial side of the knee causing a varus stress. Localised pain and swelling, laxity during various stress test: biggest indicator.
Plain radiographs and MRIs should be conducted for this injury to ensure no other structures are damaged.
Patella Tendinopathy
Overuse injury, caused by repetitive stress on the knee.
More prevalent in jumping sports due to repetitive knee extension.
Those with tight and weak quadriceps are at increased risk of patella tendinopathy.
Patient will report an increase in symptoms following PA but overtime will progress to being present during and after.
Pain located at the proximal tendon, just under the pole of the patella
Meniscus Injury
An avascular structure which absorbs shock and provides stability to the knee joint.
Mechanism is usually knee flexion combined with direction change.
Both medial and lateral can be injured, but medial is more susceptible.
MRI gold standard.
Symptoms: pain on joint line, some peripheral swelling, clicking, catching, locking, giving way: subjective essential
