Knee Ligament Injuries

Knee Ligament Injuries

The ligaments around the knee are strong. However, sometimes they can become injured.

Knee injuries by Lakeesha Perera

Ligaments injury

Sprained Ruptured

Majority tend to stretched and quickly

settle down

CompletePartial

There are a number of different things that can cause injury to the ligaments in your knee:

You may have a direct blow to your knee or knock

into something with your knee.

Your knee may be moved outside of its usual range of movement. For example, this can happen during a fall, if you land awkwardly during sport, or after a sudden movement.


Sprains and partial tears

• Intact fibers splint the torn ones and so spontaneous healing will occur

• Adhesions may result, so active exercise is prescribed

• Aspirating the haemarthrosis and applying ice packs intermittently relieves pain

• Weight-bearing is allowed

• Knee is protected from rotation or angulation strains by a heavily padded bandage or a functional brace


Complete tears• Isolated MCL or LCL treated as above

• Isolated tears of ACL may be treated by early operative reconstruction if the individual is a professional sportsman

• Cast-brace is worn until symptoms subside, thereafter movement and muscle-strengthening exercise. This is sufficient in about half of the patients as they regain good function and need no further treatment.

• Remainder will have varying instability, late assessment will identify those who will benefit from ligament reconstruction.

• Isolated tears of the PCL are usually treated conservatively


Combined injuries

• In ACL and collateral ligament injury treatment starts with joint bracing and physiotherapy to restore a good range of movements before ACL reconstruction

• Combined injuries involving the PCL the same approach is used however all damaged structures need to be repaired


Complications

Adhesions• If the knee with a partial ligament tear is not actively exercised, torn

fibers will stick to intact fibers and bone.• The knee gives way with catches of pain, localized tenderness and

pain on lateral or medial rotation occur• Confusion with a torn meniscus can be resolved by the grinding test

or arthroscopy

Instability• The knee continues to give way and tends to get worse predisposing

to osteoarthritis. Reconstruction before degeneration is wise.


Grading Ligament Injuries

GRADE 1 No instability Good endpoint

GRADE 2 Some instability Fair endpoint

GRADE 3 Opens wide Poor endpoint


Anterior cruciate ligament injuryACL injury most often occurs during sports such as football, basketball, skiing and tennis.

The injury often happens if you land on your leg and then quickly pivot or twist your knee in the opposite direction.

About half of people with an ACL injury also have injury to their meniscus or another ligament in the same knee.

Woman > men



Types of ACL Tears

Physical Exam of the Knee• Inspection

• Palpation

• Range of Motion

• Special tests

• Neurovascular assessment


ACL: HISTORY

• Contact vs noncontact

• Immediate effusion (first 4-12 hr)

• Unable to continue

• Mechanism = pivot, hyperextension


ACL Special Tests

• Anterior drawer

• Lachman test

• Pivot shift test

• Valgus stress test at full extension!


ACL: PHYSICAL EXAM• Decreased ROM• Effusion-hemarthrosis, immediate• + Instability tests

• Lachman: most accurate• Pivot shift• Anterior drawer

• + MCL and meniscus tests


“Partial” ACL tear• > 40% ACL substance• + Lachman, - pivot shift• Clinically

• Most behave functionally as full tears

• Continued shifting ↑’s risk of meniscus damage

• Rx as full tear


ACL TREATMENT

• Grade 3- Nonsurgical• modify activity

• splint & crutches, Closed chain WB to strengthen

• PRICES

• Hamstrings, gastroc!

• Functional bracing

• 100% @ 9-12 months


ACL TREATMENT

• Grade 3 Injuries- Surgery• Indications

• Most active people will require surgery to restore adequate function and decrease instability

• Recurrent instability• Inability to modify activity• Associated injuries: meniscus• Age

• Wait three weeks due to arthrofibrosis risk• 100% @ 6-12 months


Posterior cruciate ligament injury

Not as common as an ACL injury. Because the PCL is wider and stronger than the ACL.

PCL sprains usually occur because the ligament was pulled or stretched too far, anterior force to the knee, or a simple misstep.

PCL injuries disrupt knee joint stability because the tibia can sag posteriorly.


The ends of the femur and tibia rub directly against each other, causing wear and tear to the thin, smooth articular cartilage.

This abrasion may lead to arthritis in the knee

There are a number of ways that the PCL can become injured.For example, It may be injured during a car accident if the front of your bent knee hits the dashboard.



It may also be injured from falling on to your bent knee.

Your PCL can also be injured if your knee is hit from the front whilst your leg is stretched out in front of you with your foot on the ground - for example, during a game of football.

At first, some people with a PCL injury may not have much in the way of symptoms .

It may take a while for you to realize that there is a problem.

For example, you may later notice pain that comes on when going up and down stairs or when starting a run; or, your knee may feel unstable when walking on uneven ground.


PCL INJURIES PHYSICAL EXAM

• + Effusion

• + Posterior drawer test

• + Posterior sag sign

• False positive Lachman test

• Common to have isolated injuries


PCL INJURIESTREATMENT

• PRICES• Functional bracing (early)• Rehab• Surgery if continued instability, effusions


Non-operative• Aggressive rehab• Focus quadriceps• No support for bracing• closed kinetic chain• Open kinetic chain extension avoided• 90% quads strength prior to normal athletics

Medial collateral ligament injury

Injuries to the MCL can happen in almost any sport and can affect people of all age groups.

They often happen when your leg is stretched out in front of you and the outer side of your knee is knocked at the same time - for example, during a rugby or football tackle.


MCL INJURIESPHYSICAL EXAM

• Tender to palpation along MCL• Pain + instability with valgus stress

• 30o flexion = MCL• 90o flexion = associated ACL

• Pain with Apley’s distraction test• COMPARE SIDES

MCL INJURIES Treatment Of Grade 1 &2

• Early mobilization• Weight-bearing as tolerated• Hinged knee brace• PRICES• Recovery 4-6 weeks


MCL INJURIES Treatment of Grade 3 (full tears)

• Isolated = nonsurgical management• Combined = surgery consistent with associated

injuries• Natural Hx = lack of long-term degenerative changes

seen with ACL, meniscus


Lateral collateral ligament injury

Injury to the LCL is less common than injury to the MCL. This is because your other leg usually protects against injury to the inner side of your knee.

(It is usually a direct blow to the inner side of your knee that causes an LCL injury.)

But, this ligament injury can sometimes happen if one leg is stretched out in front of you and doesn't have the other leg for protection - for example , during a rugby or football tackle.


What are the symptoms of a knee ligament injury?If you have injured one or more of the ligaments in your knee, the symptoms are likely to be similar regardless of the ligament that is injured.

The severity of the symptoms depends on the degree of the injury to the ligament. For example, a ligament that is completely torn may produce more in the way of symptoms than a ligament that is just sprained (stretched).


Symptoms can include:

1.A popping sound, or a popping or snapping feeling

2. Swelling of your knee.


Can hear at the time of injury if ligament completely torn

Bleeding inside from the damaged ligament

It leads to swelling

Completely torn ligament Minor ligament sprains

3. Pain in your knee. depend on the severity of the knee injury.

4.Tenderness around your knee on touching. This may be minor sprains ----mild tenderness over the actual ligament ligament torn -----more generalised and severe tenderness

5. Not being able to use or move your knee normally. complete ligament tears--- severely reduce

minor sprains----relatively good


6. A feeling that your knee is unstable or perhaps giving way if you try to stand on it. This may cause you to limp. Again, this depends on how severe the ligament injury is. You may be able to stand if you only have a minor sprain.

7. Bruising around your knee can sometimes appear, although not always. It may take some time for bruising to develop.


Historical Clues to Knee Injury DiagnosesNoncontact injury with “pop” ACL tear

Contact injury with “pop” MCL or LCL tear, meniscus tear, fracture

Acute swelling ACL tear, PCL tear, fracture, knee dislocation, patellar dislocation

Lateral blow to the knee MCL tear

Medial blow to the knee LCL tear

Knee “gave out” or “buckled” ACL tear, patellar dislocation

Fall onto a flexed knee PCL tear


Special tests for ligaments

• Assess stability of 4 knee ligaments via applied stresses*

Anterior CruciatePosteriorCruciate

Lateral CollateralMedial Collateral


The stabilizing roles of each ligament include:

prevents the knee from buckling inwards (valgus injury)

prevents the knee from buckling outwards (varus injury)

prevents the tibia from sliding forward under the femur

prevents the tibial from sliding backward under the femur


MCL

LCL

ACL

PCL

Stress Testing of Ligaments

Use a standard exam routine Direct, gentle pressure No sudden forces

Abnormal test Excessive motion = laxity Soft/mushy end point**


Normal Stability

• Normal test is no motion with varus and/or valgus stress with knee in neutral and 30 degrees of flexion

• Lachman’s test assesses Anterior Cruciate Ligament:• Normal test is <5mm of forward movement of tibia on

femur with knee at 30 degrees of flexion

With knee in 90 degrees of flexion and foot stabilized, normal test will have <5mm of anterior motion (assessing ACL) or <5mm of posterior motion (assessing PCL)


Medial and Lateral collateral ligaments

Anterior and posterior drawer testing assesses ACL and PCL

Anterior and Posterior Cruciate Ligaments' control anterior/posterior motion

Normal end point of ligament that examiner feels with applied stress is FIRM.

A soft or mushy end point implies ligament damage (stretching or complete tear).


Collateral Ligament Assessment

Patient and Examiner Position*


*Position patient supine on table with thigh resting on edge of exam table and foot supported by examiner

• Knee in 30 degrees of flexion –

WHY? Increased laxity of medial side of knee in extension may indicate additional damage to posterior structures (posterior joint capsule & PCL)


Valgus Stress Test for MCL*

Note Direction Of Forces


*VALGUS (MCL) stress

• Proximal hand on lateral aspect of knee holds and stabilizes thigh

• Distal hand directs ankle laterally• Attempt to open knee joint on medial side • Estimate the medial joint space and evaluate the

stiffness of motion.

• Positive test = Significant gap in medial aspect of knee with valgus stress = MCL injury.


Varus Stress Test for LCL*

Note direction of forces


*VARUS (LCL) Stress • Supine position, with knee at 20 to 30 degrees of

flexion and thigh supported. • Stabilize medial aspect of knee and push ankle

medially, trying to open knee joint on lateral side

• Disruption of LCL is indicated by difference in degree of lateral knee tautness with varus stress. Compare affected knee to uninjured side


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Lachman Test*• Patient Position• Physician hand placement


*Lachman Maneuver more sensitive and specific for ligamentous tears than drawer sign.

• Patient is supine

• Knee flexed to 20-30 degrees

• Hand placement:

• Grasp and stabilize patient’s thigh just proximal to patella• With opposite hand, try to move proximal tibia forward on femur• POSITIVE TEST = Excessive forward motion of tibia (>5mm)

without firm endpoint indicates ACL damage


• Modification for patient with large thighs:• Thigh placed over knee of examiner

• Push downward on femur with hand while other hand grasps proximal tibia, attempting to move it anteriorly


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Lachman Test

• View from lateral aspect*



Anterior Drawer Test for ACL

• Physician Position & Movements*• Patient Position

Note direction of forcesKnee injuries by Lakeesha Perera

*Patient Position• Supine • Flex hip of affected knee to 45 degrees • Bend knee to 90 degrees• Patient's foot planted firmly on examination table

Physician position:Sitting on dorsum of foot, place both hands behind knee Once hamstrings relaxed, try to displace proximal leg anteriorly

Anterior drawer test is LESS SENSITIVE for ACL damage than Lachman’s Maneuver


Posterior Drawer Testing- PCL*



*Patient Position• Supine• Affected knee at 90 degrees of flexion• Determine ‘neutral’ position by comparing resting position with unaffected

knee

Physician Position & Movements• Patient's foot placed between examiner's legs while the palms of the hands are

used to push the tibia posteriorly. • Tester directs pressure backward upon proximal tibia, similar to Anterior Drawer

Testing

Interpretation of test:• Posterior instability - PCL injury indicated by increased posterior tibial translation• Confusion - trying to distinguish abnormal translation of tibia on femur - from

excessive ACL or PCL laxity



Signs• tenderness

• possible clicking

Symptoms• Pain• catching • buckling

• Commonly injured part

Meniscal Tears

• Can occur combine with other ligament – ACL mostly

Occur during twisting motions with the knee flexed

• Older people can injure the meniscus without any trauma as the cartilage weakens and wears thin over time, setting the stage for a degenerative tear.

• Medial Menisci: more prone to injury because of its restricted anatomy due to attachment to the joint capsule and to the tibial collateral ligament make it less mobile.



Meniscus Tears

Mechanism Pattern of tear

bucket handle horizontal

degenerative

traumatic

The split is vertical, along the circumference of the meniscus leaving anterior and

posterior segments attached loosely .

Sometimes the torn part displaces towards the center, causing “locking” (extension block).

Usually degenerative in origin or due to repetitive minor trauma, or with association with meniscal cysts.

Generally speaking, most of the meniscus is avascular, except the outer third-from capsule-, due to this spontaneous repair doesn’t occur.

*The loose part act as a mechanical irritant causing recurrent synovial effusion, and in severe cases secondary osteoarthritis.


Menisci Tears

Clinical Features:

Patients may complain of pain at the joint line area, locking, clicking, giving way, and swelling with activity.

In ptn >40yrs the main complaint is recurrent giving way or locking.

Physical exam:• Joint line tenderness (Mostly medial).• Joint held slightly flexed.

• Joint effusion may be present.

• In late cases quadriceps are wasted.

• Flexion is full , extension limited.


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Assess Meniscus – Knee Flexion

• Most sensitive test is full flexion*• Examiner passively flexes the knee or has patient

perform a full two-legged squat to test for meniscal injury

• Joint line tenderness**• Flexion of the knee enhances palpation of the anterior

half of each meniscus


Joint line tenderness: the most imp and specific test

_ Apley’s grind test:• Isolates meniscii• Prone with knee flexed, axial load and rotation.

- McMurray’s test• Flex/ext with varus / valgus and int/ext rotation.• Goal is to get torn piece to pop in and out of place.• Positive if pop or reproduction of pain.


Menisci Tears

Imaging

X-ray – Normal

MRI – most useful may reveal tears missed by arthroscopy

Arthroscopy : Diagnostic and therapeutic.

You have to be certain that the lesion you can see is the one causing the patient’s symptoms.


Menisci Tears Treatment

Conservative treatment of meniscal injuries begins with RICE (Rest, Ice, Compression, and Elevation).

Arthroscopy is the preferred method.

peripheral tears – surgery.

The displaced portion should be excised.

Postoperative physiotherapy.

Surgical treatment of symptomatic meniscal tears is recommended because untreated tears may increase in size and may abrade articular cartilage, resulting in arthritis.



Knee Ligament Injuries

Documents

repaired knee injuries

functional brace knee

ligament reconstruction

ligament rupture

partial ligament tear

torn fibers

torn ones

torn meniscus