Select Disorders of the Knee 79 slides--BULK OF FINAL!! Flashcards
Medial Collateral Ligament (MCL)
– Opposes extreme abductive and/or valgus forces
– Most frequently injured ligament in the knee
• Lateral Collateral Ligament (LCL)
– Limits excessive adductive and/or varus pressures
• Anterior Cruciate Ligament (ACL)
– Serves as the primary knee stabilizer, preventing forward displacement
of the tibia on the femur
– Braces against excessive ant. translation in anteroposterior (AP) plane
• Posterior Cruciate Ligament (PCL)
– Braces against excessive post. translation in anteroposterior (AP) plane
KNOW
ACL
is small (size of little finger)
More vulnerable then PCL (size of thumb)
Menisci (Medial & Lateral)===Medial meniscus is smaller, more fixed than the lateral meniscus; predisposes it to injury
KNOW
Bursae X 5
Suprapatellar
Prepatellar
Superficial and Deep Infrapatellar
Pes Anserine
________ _______
An abnormally high patella in relation to femur
Patella Alta
Normal Q-angle: • Men: \_\_\_ degrees • Women: \_\_\_\_ degrees If outside normal ranges, may be a precursor for overuse injuries
13
18…WOMEN MORE VALGUS DUE TO WIDER HIPS
Suspected knee dislocation?
Relatively rare injury but important to recognize because coexistent vascular injury, if missed, may lead to limb loss
Assess for discrepancy in ____ _____ compared to the unaffected leg
NOTE: presence of normal pulses does NOT rule out
presence of clinically significant vascular injury *
An ankle-brachial index (ABI) less than ____
____________ can rule out a vascular injury
distal pulses
0.9
Arteriogram
Ankle/Arm (Brachial) Index–Measurements usually taken
using Doppler Ultrasound device with a vascular probe,
For example: • 95 (ankle systolic pressure) • 130 (brachial systolic pressure) ABI = Ankle systolic/brachial systolic • 95/130 • The ABI is 0.73
NORMAL = resting ankle-brachial index is—–1 or 1.1
normally LE BP is greater than the UE BP or about the same
A RESTING ankle-brachial index of less than 1 is
____________ (or Borderline)
Indicates Peripheral Artery Disease (PAD)
Slight drop in ABI with exercise, even with normal ABI at rest, also suggests PAD
abnormal
Anterior Knee Pain
1---Patellofemoral Pain Syndrome AKA: • Patellofemoral disorder • Patellar malalignment • \_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_ – Most common knee problem in clinical practice
—Usually related to _________ not trauma
Clinical Presentation--------------- Anterior knee pain (often diffuse) Associated crepitus Pain with squatting Associated with repetitive activity Worse with going up stairs and prolonged sitting Associated with activities which create high compressive loads • climbing stairs • Squatting • running or jumping
Treatment:—————
1) Patella motor control exercises
short arc, quad sets, mini-squats, rockerboard
Runner’s knee
overuse
**pain is worst between 30-45 degrees of flexion (contact point)
Anterior Knee Pain
2—-Chondromalacia Patella
—-Primarily a soft tissue disorder
—-Actual damage to the underlying patellar cartilage
—Degeneration of the _____ ______ on the back
surface of the patella
hyaline cartilage
Anterior Knee Pain
3—Patellar Tendinitis
—AKA “________ _______”
Classic Presentation
–
Jumper’s Knee
Anterior Knee Pain
4—-Quadriceps Tendinitis
>30 years of age
Insidious onset
Pain anterior knee superior to patella
Staging
Stage 1: Pain after activity, no functional impairment
Stage 2: Pain early in activity that goes away after
warmed up, but returns later in exercise
Stage 3: Constant pain at rest and inability to participate in activity
Stage 4: Complete tendon rupture
Stages 3 or 4 may require ____ for repair
surgery
Anterior Knee Pain
5—Prepatellar Bursitis
AKA “_______ ________”
Swelling anterior to patella
Housemaid’s knee
Anterior Knee Pain
6--Infrapatellar Bursitis 2 TYPES!! 1) Superficial 2) Deep • Both may follow \_\_\_\_\_\_ \_\_\_\_\_\_\_\_ • Both may result in local, painful, fluctuant swelling near the tendon – Superficial = OVER the tendon – Deep = BEHIND the tendon
Management
• Ultrasound, Ice, Stretching, CMT
direct trauma
Anterior Knee Pain
7–Osgood-Schlatter’s Disease
Classic Presentation
• 11-15 y.o.
• males > females
• history of a single violent injury or repetitive knee flexion & extension
• Localized pain, tenderness & swelling about the _______ _____(almost pathognomonic)
• Pain with resisted quad contraction
• 25-50% of cases are bilateral
• May have chronic course over months or years, but usually ceases by age 18
tibial tuberosity
***Often associated with tight quadriceps
Anterior Knee Pain
8—-Plica Syndrome
Plica:
Synovial folds of the knee
Embryonic remnant
Reabsorbed by birth but present in 20-50% of knees
• Can mimic _______ pathology
• Suprapatellar Plica
• Medialpatella Plica
Snapping & pain with repetitive flexion & extension
Tender to palpation medial to patella with knee flexed
Stretching, corticosteroids, surgery if persistent
(8 weeks)
X-rays normal & often missed on MRI
meniscus
Medial Knee Pain
1—-Partial MCL Sprain:
Hyperpronation & overuse will cause chronic sprain
Follows twisting strain of the flexed knee or valgus force
Pain, tenderness, & swelling along the medial joint line
2---MCL Sprain First Degree (Grade 1)– up to 5 mm of motion Second Degree (Grade 2)– 6 to 10 mm of motion Third Degree (Grade 3)– up to 15 mm of motion
3—Complete MCL Tear:
– Follows marked _______ & _________ of the leg with
the knee partially flexed, or abd with knee extended
– Hematoma, pain, & edema over the medial joint
line
abd & ext rotation
Medial Knee Pain
4—Medial Meniscus Tear
Medial Meniscus
• Partially flexed knee suffers a twisting injury
• ______ is often fixed to the ground, while the thigh is
violently twisted
• Audible pop, tearing sensation, or severe pain
• Warmth, swelling (develops over many hours), and tenderness at the medial joint line
• Weight bearing is often intolerable, and pain is concentrated at joint line
• ________ _______ that may be relieved by pulling,
twisting, or shaking the leg
• MRI for definitive DX
• Degenerative tear is slower in onset and milder in symptoms
Foot
Locking sensation
**Recall:
• Menisci are without pain fibers
• the tearing and bleeding into peripheral attachments,
as well as the traction on the joint capsule, causes
discomfort
Medial Knee Pain
5–Terrible Triad (aka. O’Donoghue’s Triad):
_____&_____ and medial meniscus tear
The classic “terrible triad” involves valgus stress to the
knee with resultant acute injury to the ACL and MCL
NOTE: The medial meniscus tear is now thought to
occur later, as a result of chronic ACL deficiency
6—_________ Test—High diagnostic accuracy rate:
94% in the detection of tears of the medial meniscus
96% in the detection of tears ofthe lateral meniscus
Low rate of false-positive and false-negative
MCL, ACL
Thessaly
Medial Knee Pain
7—Bursitis
A. MCL Bursitis
Pain without locking along the medial joint line
Tenderness to palpation of MCL, INCREASED pain with ________ stress
Often diagnosed as med meniscus tear and treated with arthroscopy
23% may show unassociated meniscus tear
B. Pes Anserine Bursitis
Pain at the insertion of the sartorius, gracilis, and semitendinosus
Pain, local tenderness, and swelling over the anteroMEDIAL, PROXIMAL tibia _________ the joint line
Intensified by climbing stairs and walking
Generally NO increase in pain with valgus stress in 30 degrees knee flexion
Often mistaken for OA
valgus
below
Medial Knee Pain
8—Tendinitis
A. Gastrocnemius Tendinitis:
Causes _____ knee pain that mimics pes anserine bursitis
Pain is located b/w the pes anserine tendons and the gastrocnemius
B. Semimembranosus Tendinitis:
Aching pain over the __________ aspect of the knee just inferior to the joint line
Provoked by walking, bending, lifting, climbing, running
Often associated with hyperpronation of the ipsilateral foot
medial
posteromedial
Lateral Knee Pain
1—LCL Strain
Fall or blow to the knee with the leg ______ rotated and varus stress applied
Pain over the LCL, minimal joint effusion
Walking causes some pain, but running or cutting
cause pain and a sense of “giving way”
Varus stress at 30 degrees (+)
internally
Lateral Knee Pain
2—Lateral Meniscus Tear
Follows twisting injury with knee FLEXED
Local tenderness over lateral joint line
Locking that prevents full ________ may occur, but is
less common than with medial tears
Joint effusion
extension
Lateral Knee Pain
3—Popliteus Tenosynovitis
Inflammation of the tendon sheath lining**
Popliteus: Flexes and medially rotates the tibia in
the open chain (non-wt bearing), laterally rotates the femur (closed)
Lateral knee pain during weight bearing with the knee flexed 15 -30 degrees
Similar complaints to _____ ________
Downhill running or walking aggravates, especially banked surfaces
Less or no pain up hill because the muscle does not have to prevent forward tibial displacement
Rest relieves
Pain may be perceived as arising in the knee since a portion of the tendon is intraarticular
ITB syndrome
Lateral Knee Pain
4—Iliotibial Band Friction Syndrome
• Common in runners (sedentary may also develop)
• Pain on the _______ side of the knee that can refer to the insertion at Gerdy’s tubercle
• Pain gradually INCREASES over days to weeks
• Worse with downhill running (esp. with knee extension just before heel strike) may cause runner to stop
• REST relieves, returns upon resuming activity
• Tender at __________ epicondyle
• Increased tenderness while flexing and extending knee (Noble’s)
• Friction between ITB and condyle over bursa causes irritation (30-40 degrees flexion)
• Common causes: Tight ITB, running and hyperpronation
lateral
lateral
Posterior Knee Pain
1---Baker’s Cyst AKA: popliteal cyst • Not considered to be a true bursitis • Synovial cyst: • located \_\_\_\_\_\_\_ to the MEDIAL femoral condyle, between tendons of the gastrocnemius and semimembranosus muscles
**Usually seen in patients with RA or DJD
***Compression of the tibial nerve or venous obstruction
mimicking thrombophlebitis or peripheral neuropathy
posterior
Posterior Knee Pain
2—Gastrocnemius Strain
Tearing or ripping pain after a sudden start or turn
Pain may come and go with walking or running
Local tenderness and swelling
• MC cause of “_______ _________”
Tearing of musculotendinous junction of MEDIAL head of
gastrocnemius
Tennis Leg
Posterior Knee Pain
3—Hamstring Strain
—Forced ____________ of knee
– Tenderness and swelling to muscle
extension
Biomechanics of ACL Tears
Associated with anterior blows that _________ the knee, excessive noncontact hyperextension of the knee, and extreme deceleration forces to the knee (sudden stopping or cutting)
78% result from _________ deceleration & change in direction at the knee
• Swelling within 1-2 hrs
• Pain may be mild or absent in 30% (rupture)
• “______ _________” in 36% of cases and moderate to severe anterior knee pain in 70%
• Exam of the knee with painful acute ________ unreliable
• Midsubstance tears often rupture the middle geniculate artery resulting in hemarthrosis
• MRI or scope is most diagnostic
hyperextend
sudden
Popping sensation
hemarthrosis
ACL Tear
- -Patient presents in either acute or chronic phase
- –An acute knee injury heralded by a ____ OR_____, followed by a rapidly evolving effusion, almost always affirms a rupture of the ACL
pop or snap
Biomechanics of PCL Tears—-Posterior directed force applied to the proximal tibia with the knee flexed
PCL tears typically report falling on a ____ knee or
sustaining a severe direct blow to the _______ aspect of the knee.
This injury pattern displaces the tibia backward and pulls apart the PCL
eg. when the knee strikes the dashboard in a motor vehicle accident
Patellar injury with disruption of normal articulation or fracture may also result
Look for abrasions, contusions, or lacerations over the knee region
Onset of edema & pain tends to occur within the first 3 hrs after injury
PCL harm often signifies a major injury and rarely occurs
as an isolated injury
flexed
anterior
Osteochondritis Dissecans (OD)
Classic Presentation
• 14-yo male athlete (may occur in adults too)
• Insidious onset, ant knee pain, causing patient to limp,
occasionally locks and swells
• B/L in 20% of cases
Cause
• ______ _______ separates and can dislodge into the joint
• Thought to be due to disturbed vascular supply &/or trauma
Management
• Rest and protection – partial or complete remission in 30%
• Surgical excision indicated if healing does not occur
• OA is a common long-term complication
Bone fragment
