knee clinical conditions pt 1 (DFF to Patellofemoral Pain) Flashcards
includes both supracondylar and condylar regioms
distal femur fractures
zone between femoral condyles and the junction of metaphysis w femoral shaft
comprises the distal 10 to 15 cm of femur
supracondylar area
extends more distally and is mire convex than lateral femoral condyle
physiologic valgus of femur
medial condyle
this flexes distal fragment, causing posterior displacement and angulation
gastrocnemius
they exert proximal traction, resultimg in shortening of lower ex
quads and hamstrings
mechanism of injury of distal femur fractures
severe axial load w varus, valgus, rotational force
mechanism of injury of distal femur fracture in young adults
high energy trauma like motor vehicle collision or fall from a height
mechanism of injury of distal femur fracture in elderly
minor slip or fall onto a flexed knee
general principles of dff treatment
- restore articular congruity
- rigid stabilization of articular fracture
- indirect reduction of metaphyseal component to preserve vascularity of fractyre fragments
- stable (not necessarily rigid) fixation of articular block to shaft
- early knee ROM
intervention of stable non operative fractures of dff
hinged knee brace w partial weight bearing
full time bracing for 6-8 wks, closed chain rom at 3-4 wks
non operative intervention of displaces fractures in dff
6-12 wks period of skeletal traction followed by bracing
complication of skeletal traction
varus and internal rot deformity, knee stiffness, prolonged hospitalization and bed rest
indications of non operative treatment of dff
nondisplaced or incomplete fractures, impacted stable fractures in elderly pts, severe osteopenia, advanced underlying medical conditions, gunshot injuries
operative treatment. indicated for extra articular fractures and simple intra articular fractures
retrograde intramedullary (im) nail
operative treatment, indicated when associated with pre existing joint arthroplasty and select cases when stable internal fixation not achievable
arthroplasty (metal implant)
uncommon injury that may be limb threatening, orthopedic emergency
knee dislocation
significant soft tissue injury of knee dislocation
ruptures of at least three or four major ligamentous structures of the knee
most common knee dislocation
posterolateral
complications if knee dislocation
vascular injury, neurologic injury, stiffness/ligament, ligamentous laxity
nerve affected if neurologic injury of knee dislocation occurs
peroneal nerve, fibular nerve
+ foot drop if there is injury
most common complication of knee dislocation
stiffness/arthrofibrosis
treatment for knee dislocation
emergent reduction if pt did not present reduced
revascularize within 6 hrs if there is significant arterial injury
care for soft tissue injuries (open knee dislocations)
ligament reconstruction
largest sesamoid bone in body, articular cartilage may be up to 1cm thick
patella
articular facets of patella
7 articular facet, lateral facet is largest
most common type of patellar dislocation
lateral dislocation
ensures that the resultant vector of pull with quadriceps action is laterally directed
Q angle
Q angle in women is ______ degrees greater than men
4.6 deg
lateral moment is normally counterbalanced by
patellofemoral
patellotibial
retinacular structures
patellar engagement within the
trochlear groove.
predisposes to patella dislocation
increases tendency of patellar dislocation because it can move more lateral
Increased/wider Q angle
Why is Lateral patellar dislocation more common in Women
Women have higher Q angle
Ligaments of women are lax
functions of patella
increase the mechanical advantage and leverage of the quadriceps tendon
aid in nourishment of the femoral articular surface
protect the femoral condyles from direct traum
Reduction and casting or bracing in knee extension
- Usually for first time dislocation
may ambulate in locked extension for 3 weeks, at which time progressive flexion can be instituted with physical therapy for quadriceps strengthening
- Isometrics, no aggressive ROM
after 6 to 8 weeks, patient may be weaned from the brace as tolerated
Non-operative treatment for Patellar Dislocation
primarily used with recurrent dislocations
no single procedure corrects all patellar malalignment problems
patient’s age, diagnosis, level of activity, and condition of the patellofemoral articulation must be taken into consideration
Operative treatment for Patellar dislocation
Surgical interventions for Patellar disloc
Lateral release
Medial plication
Proximal patella realignment
Distal patellar realignment
Test for patellar disloc
+ apprehension test
hemarthrosis (there’s bleeding inside)
inability to flex the knee
displaced patella on palpation
patients with reduced or chronic patella dislocation may demonstrate a positive apprehension test
Clinical evaluation for Patellar Disloc
Not common
Represent 1% of all skeletal injuries
Male-to-female ratio (2:1)
Most common age group 20 to 50 years old
Bilateral injuries (uncommon)
Patellar Fracture
Trauma to the patella may produce incomplete, simple, stellate, or comminuted fracture patterns.
minimal displacement owing to preservation of the medial and lateral retinacular expansions
abrasions over the area or open injuries are common
active knee extension may be preserved
Direct mechanism of injury for Patellar fracture
most common
secondary to forcible quadriceps contraction while the knee is in a semiflexed position (e.g., in a a stumble or a fall)
intrinsic strength of the patella is exceeded by pull of the musculotendinous and ligamentous structures
transverse fracture pattern
active knee extension is usually lost
Indirect mechanism of injury for Patellar Fracture
Most common mechanism of injury for Patellar fracture
Indirect
Classification of Patellar fracture
Undisplaced
Transverse
Lower or upper pole
Multifragmented undisplaced
Multifragmangted displaced
Vertical
Osteochondral
cylinder cast or knee immobilizer for 4 to 6 weeks
early weight bearing to FWB with crutches as tolerated
early SLR and isometric quadriceps strengthening
exercises should be started within a few days
After radiographic evidence of healing, progressive active flexion and extension strengthening exercises are begun with a hinged knee brace initially locked in extension for ambulation
Non operative treatment for Patellar fracture
Indications for Non operative treatment for Patellar fracture
nondisplaced or minimally displaced (2- to 3-mm)
fractures with minimal articular disruption (1 to 2 mm)
requires an intact extensor mechanism
Techniques
- tension band wiring
- screws
- circumferential cerclage wiring
retinacular disruption should be repaired
postoperatively, patient should be placed in a splint for 3 to 6 days until skin healing, with early institution of knee motion
AAROME, progressing to partial and full weight bearing by 6 weeks
Operative treatment for Patellar Fracture
Indications of operative treatment for patellar fracture
> 2-mm articular incongruity
3-mm fragment displacement
open fracture
major weight-bearing bone of the leg (85% load)
Tibia
composed of the articular surfaces of the medial and lateral tibial plateaus,
separated by the intercondylar eminence (nonarticular, attachment of the cruciate ligaments)
10-degree posteroinferior slope
Tibial plateau
larger and concave
medial plateau
extends higher and convex
lateral plateau
3 bony prominences 2 to 3 cm distal
tibial tubercle: patellar tendon
pes anserinus: medial hamstrings
Gerdy’s tubercle : iliotibial band)
More common tibial plateau fracture
Lateral Plateau fractures
tibial tubercle: patellar tendon
pes anserinus: medial hamstrings
Gerdy’s tubercle : iliotibial band)
Medial plateau fractures
Mechanism of Injury for Tibial Plateau fractures
Varus or valgus forces coupled with axial loading
bicondylar split fracture results from a severe axial force exerted on a fully extended knee
MVA
split fractures + ligamentous disruption
Mechanism of injury for Younger Indiv
Falls
depression and split-depression fractures
lower rate of ligamentous injury
Mechanism of injury for Elderly px w osteoponic bone
Associated Injuries of Tibial Plateau fractures
Meniscal tears (50%)
Cruciate or collateral ligament injuries (30%)
Peroneal nerve or popliteal neurovascular lesions
Young adults: highest risk of collateral or cruciate ligament rupture
Cruciate or collateral ligament injuries (30%
Medial tibial plateau fractures
Peroneal nerve injuries are caused by stretching (neurapraxia) which usually resolve over time
Arterial injuries
Peroneal nerve or popliteal neurovascular lesions
traction induced intimal injuries presenting as thrombosis (transection injuries secondary to laceration or avulsion is rare)
Arterial injuries
caused by stretching (neurapraxia) which usually resolve over time
Peroneal nerve injuries
AP and lateral views supplemented by 40-degree interna
lateral plateau
external rotation
oblique views
medial plateau
useful for delineating the degree of fragmentation or depression of the articular surface
3D CT Scan
useful for evaluating injuries to the menisci, the cruciate and collateral ligaments, and the soft tissue envelope
MRI
Avulsion of the fibular head
Segond sign
Pellegrini-Steida lesion
Signs of associated ligamentous injury
lateral capsular avulsion - ACL injury
Segond sign
calcification along the insertion of the medial collateral ligament
Pellegrini-Steida lesion
Classification for Tibial Plateau Fracture
Schatzker Classification
Type I: Lateral plateau, split fracture
Type II: Lateral plateau, split depression fracture
Type III: Lateral plateau, depression fracture
Type IV: Medial plateau fracture
Type V: Bicondylar plateau fracture
Type VI: Plateau fracture with separation of the metaphysis from the diaphysis
are low-energy injuries
Types I to III
are high-energy injuries
Types IV to VI
usually occurs in older individuals
Type III
usually occurs in younger individuals and is associated with medial collateral ligament injuries
Type I
for nondisplaced or minimally displaced fractures and in patients with advanced osteoporosis
protected weight bearing and early ROM in a hinged fracture-brace
isometric quadriceps exercises and progressive passive, active-assisted, and active ROM exercises
Partial Weight Bearing (PWB) (30 to 50 lb) for 8 to 12 weeks is allowed, with progression to FWB
Non operative treatment for Tibial Plateau fracture
articular step-off >2mm
Instability >10 degrees of the nearly extended knee compared to the contralateral side
Split fractures more unstable than pure depression fractures
Open fractures
Compartment syndrome
Associated vascular injury
Operative treatment for Tibial plateau fracture
Postoperative: non-weight bearing with continuous passive motion and AROM
Weight bearing is allowed at 8 to 12 weeks
Rehab for Tibial Plateau Fracture
Knee stiffness
Infection
Compartment syndrome
Malunion or nonunion (Schatzker VI)
Post-traumatic arthritis
Peroneal nerve injury
- Causing foot drop deformity
Popliteal artery laceration
Avascular necrosis of small fragments (results to loose bodies)
Complications of Tibial Plateau Fracture
characterized by pain in the vicinity of the patella that is worsened by sitting and climbing stairs, inclined walking and squatting
Patellofemoral Pain
Incidence of Patellofemoral pain
F > M if non athletic
M > F if athletic
4 classic factors implied in the genesis of the instability
trochlear dysplasia
patella alta
Increase in Q angle
patellar tilt (excessive patellar tilt with medial ligamentous disruption)
The single most important factor implied in the genesis of patellar instability
The femoral sulcus is not sufficient to provide the osseous restraint capable of avoiding patellar dislocations
Femoral trochlear dysplasia
Moving of patella causes friction, will cause pain
Patellar morphology and the amount of congruence of the patellofemoral joint
Position can be baja (below) or up (alta)
The positioning of the patella (alta or baja)
