Lower Extremity Disorders part 2 Flashcards
How do we decide when to order a knee x-ray?
Ottawa Knee Rules: Radiograph if 1 criterion is met
- Patient age > 55 years
- Tenderness at the head of the fibula
- Isolated tenderness of the patella
- Inability to flex knee to 90 º
- Inability to bear weight for 4 steps both immediately after the injury and in the ED
a primary stabilizer of the knee preventing anterior translation of the tibia in relation to the femur
ACL
MOI of ACL tear
Sudden deceleration with rotational trauma or hyperextension force applied to the knee
-
Twisting or hyperextension injury followed by:
- Sudden pain & giving way of the knee
- Audible “pop” - Joint effusion within first few hours → increased pain
- Joint effusion
- Limited ROM → unable to bear full weight
- (+) Lachman, Anterior drawer, pivot shift tests
dx?
w/u and findings?
what imaging is often ordered to confirm dx?
- ACL tear
- XR Knee series - effusions, avulsion fracture of lateral capsular margin of tibia (Segond fracture), Tibial eminence fracture common in open growth plates
- MRI to confirm
pathology of ACL tear
- Complete rupture of ligament most often occurs
- Commonly associated with a meniscal tear - MCL, LCL, or PCL are rarely damaged
management for ACL tear
- Initial
- RICE with knee immobilizer brace, +/- crutches
- acetaminophen before NSAIDs
- aspiration if large effusion
- Start early ROM exercises as pain allows - Refer to ortho
- Young → reconstruction with graft
- Older - PT to strengthen surrounding muscles to improve stability
for ACL reconstruction with graft in young patients, the graft is taken from patients ___, ___, or ___ from a cadaver
patellar, hamstring, or quadriceps tendon
Sequelae of conservative management for ACL tear (2)
Medial meniscus tear, secondary degenerative joint disease
what ligament prevents posterior translation of the tibia in relation to the femur
PCL
MOI of PCL tear (2)
- Direct blow to the tibia - Knee strikes dashboard in MVA or fall onto knee
- Extreme hyperextension (associated ACL rupture)
2 pathologies of PCL tears
- Injuries range from a stretch injury to a complete rupture
- Often associated with other injuries - Collateral ligaments, ACL ruptures
- Same as ACL (minus special tests unless ACL is ruptured as well)
- (+) Posterior drawer test
- Assess NV status if multiligamentous injury is suspected
- Assess with ABI - if < 0.9 order arterial imaging to r/o intimal tear that could lead to thrombosis
dx?
w/u?
mgmt?
- PCL tear
- same as ACL
-
RICE, Knee immobilizer; Begin ROM after 1-5 days
- isolated PCL injuries - PT; reconstruction if PT fails
- multiligamentous injuries - reconstruction
possible complication of PCL tear
Osteoarthritis
what ligaments provide stability from varus and valgus stress
collateral ligaments
MOI of collateral ligament tear
- Medial Collateral Ligament (MCL) - lateral (valgus) blow to the knee; Football clipping injury
- Lateral Collateral Ligament (LCL) - associated with other traumatic knee injuries; Much less common
- Localized pain, tenderness, swelling and stiffness along ligament course - Worsens over 6-8 hours
- may be able to bear weight after injury
- 1-2 days after injury ecchymosis noted along ligament course and a small effusion
- Assess uninjured extremity first to gage normal laxity
-
Varus/valgus testing performed in extension and 30° flexion
- Laxity noted in extension = more significant trauma
- Instability may be masked by pain and involuntary muscle contraction
dx?
w/u?
- collateral ligament tear
- XR AP/Lat Knee; MRI to confirm
mgmt for collateral ligament tear grade I and II
Sprains-partial tear (Grade I and II)
- RICE, hinged knee brace, NSAIDs
- Early ROM exercises
- Crutches with weight-bearing as tolerated
mgmt for collateral ligament tear Grade III
Complete rupture (Grade III)
- Refer to ortho
- Tx varies based upon location of rupture - Conservative (hinged knee brace) vs. repair or reconstruction
gel-like pads that sit between the femur and tibia
Function as shock absorbers and provides a smooth gliding surface during ambulation
Menisci
MOI of meniscal injury (2)
- Rotational force of the knee while foot is planted
- Older patients (degenerative tear) - Minimal (squatting down) to no trauma
-
Pain and stiffness following MOI that progressively worsens over 2-3 days
- Ambulation after injury is possible
- may report hearing a “pop” - (+) Locking, catching, or popping noted more after effusion begins to resolve
- Tenderness along joint line of the affected meniscus - Medial meniscus MC affected
- Effusion (directly affects ROM)
- Larger effusion MC in lateral tears (closer to joint capsule)
- Small effusion seen with tears of avascular central body - (+) McMurray - painful click noted on exam
dx?
w/u?
- meniscal injury
- XR; MRI knee
meniscal injury - Add a weight bearing AP with knee in 45° flexion if pt is how old?
> 40 y/o
Provides info on amount of osteoarthritis which directly affects surgical outcomes
mgmt for meniscal injury?
- initial - RICE, NSAIDS
- arthroscopic repair if indicate
- No indications for surgery → initial management then PT
Indications for referral to ortho for arthroscopic repair
- Young patients with traumatic tear
- Failure to conservative therapy (persistent joint line tenderness)
- Mechanical symptoms
- Evidence of ligamentous instability
MOI of knee dislocation
severe ligamentous disruption
- MVA
- Fall from height
- Trampoline falls
- Martial arts
- Spontaneous with walking in morbidly obese patients
MC in young males
how are knee dislocations characterized?
MC dislocation?
based upon direction of the tibia in relation to the femur
- anterior
- posterior
- lateral
- medial
-
deformity with severe pain and limited ROM
- 50% will spontaneously reduce - Ecchymosis and swelling
- Assess NV status
- Popliteal artery, common peroneal and tibial nerve injuries
- Limb-threatening vascular injuries are common even with normal pulses - Attempt ligamentous assessment
- May be limited due to large effusions
- Hyperextension >30° when leg is lifted by foot indicates gross instability
dx?
w/u?
- knee dislocation
- XR; CT/MRI after reduction and stabilization
management for knee dislocation
-
Reduction - longitudinal traction
- Procedural sedation
- post-reduction NV check - If distal pulses are intact, assess by ABI / angiography
- Immobilize knee in 20° flexion - Allow access to distal feet for serial NV assessment
- Post reduction imaging - Ortho and vascular surgery consultation
- Admit for serial NV checks
tibial plateau fx MOI (2)
-
Valgus stress = lateral plateau fracture (MC)
- High-energy trauma in young patient - Low-energy trauma in osteoporotic geriatric pt - Twisting or fall
- Sudden onset of pain after trauma with the inability to bear weight
- Swelling, joint effusion
- (+/-) deformity
- Limited ROM
- Assess NV status with ABI
- Look for evidence of open fx
- Assess for associated injuries
- Assess for compartment syndrome
dx?
w/u?
- Tibial Plateau Fractures
- XR; CT/MTI to evaluate amount of displacement before surgery; CTA if vascular comp
this XR is beneficial if AP/lateral are inconclusive in tibial plateau fx
oblique
mgmt for tibial plateau fx
- Initial - Compression, ice, analgesics, splinting in extension
- Displaced - Most all fractures will require ORIF
-
Non-displaced
- Long-leg posterior splint / knee immobilizer, crutches, strict non-weight bearing
- F/u with ortho within 1 week
indications for emergent consultation in tibial plateau fx
Open fx, NV compromise, compartment syndrome
indications for urgent consultation (within 24-48 h) for tibial plateau fx
- Fractures with any displacement or depression
- Most all fractures will require ORIF
- Sudden force to flexed knee with quadriceps contracted
- Knee flexion at the beginning of a jump or an awkward landing
dx?
Tibial Tubercle Fracture
- MC in children - Bones with open growth plates
- Pain, tenderness, and swelling over tibial tuberosity
- Displacement of patella superiorly
- Loss of ROM
dx?
w/u?
mgmt?
- tibial tubercle fx
- XR knee - 2 views
- mgmt
- Incomplete/small avulsion: RICE; Knee immobilizer, long leg posterior splint, no weight bearing; Refer to ortho within 1 week
- Complete avulsion: RICE; Knee immobilizer, long leg posterior splint, no weight bearing; Urgent ortho consult for ORIF (24-48 h)
Most common long bone fracture
Most often in association with fibular fracture
Tibial Shaft Fracture
MOI of Tibial Shaft Fracture (adults & children)
- Adults: high-energy direct blow to the tibia
- Children: twisting injury
presentation of tibial shaft fx
- inability to bear weight
- Pain, swelling, deformity
- Assess for common complications: Open fracture, NV compromise, Compartment syndrome
diagnostics for tibial shaft fx
- AP and Lateral Tibia/Fibula XR - Add on knee and ankle if associated injury is suspected
- Add oblique XR / CT - Further evaluate complexity of fracture
- Bone scan if occult fx is suspected
mgmt for tibial shaft fx
- Initial - RICE, analgesics, long leg posterior splint
- Emergent consultation - Open fx, Tib/fib fracture, NV compromise, compartment syndrome
-
Displaced
- Closed reduction and long leg splinting (posterior + stirrup)
- Admit for observation and monitoring of complications
- Consult ortho -
Non-displaced
- Long-leg posterior splint, crutches, strict non-weight bearing
- F/u with ortho within 1 week
- Isolated fracture uncommon, most often associate with tibia fx
- MOI: Direct blow to the lower leg; Rotational force
dx?
fibula fx
- May be able to bear weight - if isolated
- Point tenderness and localized pain with swelling
- Deformity may be noted if displaced
- Assess for Maisonneuve fx
dx?
w/u?
- fibula fx
- XR - 2 views tib/fb; isolated knee/ankle if needed
Proximal fibula fx with associated medial malleolus fx or ligament disruption of ankle without fx
what type of fx?
Maisonneuve fracture