Flashcards in Hip and Lower Extremity Disorders Deck (98):
Define avascular necrosis of the hip
1. Results from loss of blood supply to trabecular bone -> collapse of femoral head
A. Trabecular bone
-Less dense, softer, weaker than compact bone
-Typically at ends of long bones proximal to joints & within vertebrae
B. Can be bilateral
When is avascular necrosis most common?
1. Can occur at any age
A. More common in 3rd - 5th decades of life
What is the etiology/RF of avascular necrosis?
2. Often complication of:
A. Corticosteroid use
-90% of cases asst w/ steroids or alcohol
-hip dislocation or femoral neck fracture
E.Sickle cell disease
F. Radiation therapy
What fx increases the risk of anfh?
Incr. risk of AVN of hip w/ femoral neck frx as opposed to other hip frx locations
What is AnFH in children?
1. In children, this disease is known as Legg-Calve-Perthes disease
2. May develop in children ages 3 – 12 yrs
Peak incidence 5 – 7 yrs
How does a child with Legg-Clave-Perthes dz present?
1. Child presents w/ limp of 2-3 wks duration, typically, at initial office visit, worse w/ activity, end of day
A. Aching in groin or proximal thigh
B.Hip abduction limitation, IR/ER limitation
What are other causes of hip pain in children?
1. Septic arthritis
2. transient synovitis
3. Perthes dz
4. Slipped capital femoral epiphysis
What are the sxs of ANFH?
1. Dull ache or throbbing pain in
B. Lateral hip
C. Proximal thighs
2. Pain w/ WB
A. relieved w/ rest
3. Loss of rotation (internal / external) or abduction
A. Walks with limp
What special tests are used to dx ANFH?
1. Trendelenburg test
2. FABER test
3. Evaulation of internal and external rotation of hip joints
What dx studies are used for ANFH?
1. X-rays: AP pelvis and lateral of hip
2. MRI hip
A. Imaging of choice
How is AVN of the hip?
1. NWB- temporary treatment until sx
2. Vascularized bone graft -> non-collapsed necrosis
3. Core decompression
4. Total hip arthroplasty -> collapse of femoral neck or bilateral involvement
Define Slipped Capital Femoral Epiphysis
1. Slippage of the the femoral head at the femoral epiphysis
What are the characteristics of SCFE?
1. Most cases are idiopathic, occurs during adolescent grwth spurt
2. Femoral epiphysis slips posteriorly -> limp and impaired internal rotation
3. Usually unilateral, 30-40% bilateral
Who is most likely to get SCFE?
1. Typically in children 10 – 16 yrs of age
2. M > F
3. Typical pt is obese child in early adolescence (12 – 13.5 yrs)
4. Participating in sports activities
What are the sxs of SCFE?
1. Gradual onset of hip, thigh or knee pain asst w/ painful limp
2. Absence of hip pain in setting of knee pain warrants investigation for SCFE
3. Most common presentation
painful limp in child w/ gradual onset or related to an injury
A. groin pain and/or anterior thigh pain can be referred to knee or only c/o knee pain
B. NEED TO EXAMINE HIP, KNEE and BACK
What are the physical exam findings for SCFE?
A. antalgic or trendelenburg
A. ROM intact w/o pain
3. HIP ROM
A. loss of IR, flexion of hip and then internally rotate
4. KNEE ROM
A. 0-145 deg, other tests normal
A. foot may be externally rotated
6. Leg lengths
A. limb may be shorter by 1-3 cm
What imaging is used for SCFE?
1. XRay:AP pelvis & Lateral x-rays -> postero- medial displacement of epiphysis
2. displacement may not be obvious but wide physis seen
A. described as ice cream falling off of a cone
What is the tx for SCFE?
2. Surgery -> pins
What are DDX for life or limb threatening causes of a limp in children?
1. Spetic arthritis
B. Metastatic neuroblastoma
C. Osteogenic sarcoma
D. Ewing's tumor
4. Torsion of testicle
9. Developmental dysplasia
11. Epidural abscess of spine
What are the different areas of hip fracture?
1. Subcapital neck
2. Transcervical neck
3. Intertrochanteric neck
5. Greater trochanter
6. lesser trochanter
What are the consequences of a hip fracture?
1. 20% mortality rate after hip fracture/surgery
2. Need to make sure we are screening for osteoporosis/osteopenia before patients get hip fracture
Do males or females have a worse hip fracture prognosis?
Males w/ hip fractures have worse mortality rate than females
What is the presentation of a hip fx?
1. Most common presentation of limb on exam*
2. Attempts to roll the limb are very painful
What imaging studies are used for hip fx?
1. Diagnosis made on plain films majority of the time
A. AP Pelvis & Lateral of affected hip
B. If negative x-rays, order MRI
What are the treatment options for a hip fx?
1. Cannulated screws (ORIF)
3. Gamma nail fixation
When is a gamma nail fixation used?
1. Inter-trochanteric fx
A. Short nail
2. Subtrochanteric fx
A. Long nail
What are the risks of hip surgery?
2. Post-op bleeding/hemorrhage
3. DVT/PE: anticoagulate for 4 weeks
5. Sciatic Nerve Palsy
6. Femoral Nerve Palsy
What is seen in imaging of OA of the hip?
1. Narrowed joint space
3. Jagged femoral head
What is the tx for hip OA?
1. Total hip Arthroplasty
Define Osgood-Schlatter Disease
1. Irritation of patellar tendon at tibial tuberosity
A. partial avulsion of the tibial tuberosity
2. Self-limiting disease that usually heals when epiphyseal plate closes
What is the etiology of Osgood-Schlatter Disease?
1. Caused by trauma or overuse, growth spurt
2. more common in athletic children
Who gets Osgood-schlatter disease?
Age of onset 8 – 15 yrs, M>F
What are the sxs of Osgood-Schlatter dz?
1. usually Bilateral Anterior Knee Pain
2. Localized pain & swelling over tibial tubercle
3. Pain typically related to activity and relieved w/ rest
A. running, jumping, kneeling
What imaging modalities are used for osgood-schlatter dz?
X-rays may be normal or may show STS
How is osgood-schlatter dz treated?
1. Refrain from aggravating physical activity for 2-3 mos., avoid jumping, running
2. Stretching, ice, NSAIDs
Define Chondromalacia Patella
Articular cartilage of knee is softened, maybe fissured
What are the sxs of chondromalacia patella?
Anterior knee Pain worse w/ climbing stairs, squatting
Why is an xray ordered for chondromalacia patella?
X-rays to r/o arthritis, chondral defect, patellar frx or patellar subluxation
What is the treatment for chondromalacia patella?
2. Quad strengthening is key (esp with stationary bike)
3. Knee brace/sleeve
What is seen on xray for chondromalacia patella?
1. Abnormal alignment
2. Fuzzy edges or fissure to the patella
What is patellar tendonitis (jumper's knee)?
1. Inflammation of patellar tendon secondary to repetitive trauma
A. athletes involved with running, jumping and kicking sports, heavy weight training
2. chronic overuse syndrome
Who gets patellar tendonitis?
1. M > F
2. usually 16-40 yo
What is the rx for patellar tendonitis?
1. Rest, Ice, activity modification
3. Patellar Strap
A. closed chain exercises- leg press or partial squats
B. maximize quad strength and knee joint flexibility
What are the sxs of patellar tendonitis?
1. aggravated anterior knee pain w/ running hills and excessive foot pronation
What are the characteristics of patellofemoral syndrome?
1. Anterior knee pain
2. Q angle > in females
3. Common in adolescents and young adults
What are the causes of patellofemoral syndrome?
1. Decreased hip strength
2. Decreased strength of thigh muscles
3. Patellar subluxation with flexion
4. Limited ankle motion or too much motion in foot
How is patellofemoral syndrome dxed?
A. usually normal AP and lateral
B. merchant view may show tipping of patella
2. Diagnosis of exclusion, therefore, may need to order MRI to r/o meniscus tear or chondral defect
How is patellofemoral syndrome treated?
1. Strengthening exercises for glutes, quads: stationary bike with seat high
2. Taping or bracing of kneecap
3. Increase motion at the ankle and/or orthotics
Define menisci and their function
1. C-shaped structures made up of cartilage
2. Provides cushion to the knee joint
A. Acts as shock absorber
3. Blood supply- medial and lateral geniculate arteries
4. Located between distal femur and tibial plateau
What is the moi for a meniscal tear?
axial loading and rotation
What are the general characteristics of a meniscal tear?
1. Meniscal injuries occur w/ excessive rotational force of femur on tibia
2. Medial meniscus > Lateral meniscus
3. Injuries may be isolated or may occur w/ other ligamentous injuries or w/ underlying arthritis
What different types of meniscal tears are possible?
3. Torn horn
5. bucket handle
What are the sxs of a meniscal tear?
1. Joint line pain on side of injury
2. +/- Inability to fully extend knee
3. Knee may feel unsteady, “giving way”
4. Gradual swelling over hours
5. Locked knee
A. bucket-handle tear
6. Walking up & down stairs or squatting difficult and painful
7. + McMurray test
What are the characteristics of a medial meniscus tear?
1. Medial knee pain worse with squatting, twisting or turning, change in direction
2. medial meniscus sxs can mimic that of a medial plica
A. synovial fold between medial condyle and patella
What are the indications for knee arthroscopy for a meniscal tear?
1. Persistent sxs unresponsive to conservative treatment
2. Irreducible locking
What is the general anatomy and function of Cruciate ligaments?
A. Proximal fibers attach to posterior aspect of lateral femoral condyle of distal femur and distal fibers attach to anterior tibia at region on tibial spines
A. Primary anterior and rotational stabilizer of the knee
Which cruciate ligament is more commonly injured?
ACL more commonly injured than PCL
What is the MOI of ACL injuries?
1. ACL injuries often asst w/ pivoting motion during running, jumping, cutting activities
What tests are used for CL tears?
1. ACL: anterior drawer, lochman's, Pivot shift
2. PCL: posterior sag. posterior drawer
What are the sxs of an ACL tear?
1. Significant twisting injury
2. “Popping” sensation
3. Knee instability
A. Usually within 2 - 4 hrs
5. Anterior drawer test- (not always reliable)
6. Pivot shift test
7. + Lachman test (compare sides)
What are the indications for a joint aspiration (arthrocentesis) in a knee injury (esp ACL tear)?
1. Dx of traumatic bony or ligamentous injury
2. Dx of septic or crystal-induced arthritis
3. Instillation of meds for acute or chronic arthritis
4. Relief of pain of acute hemarthrosis
What are the contraindications for a joint aspiration (arthrocentesis) in a knee injury (esp ACL tear)?
1. Relative Contraindications
A. Overlying cellulitis
B. Bleeding diathesis
What are the complications for a joint aspiration (arthrocentesis) in a knee injury (esp ACL tear)?
1. Potential to cause septic joint
3. Allergy to local anesthetic
What dx studies are used for an ACL/PCL tear?
1. X-rays done to r/o asst fx
A. Type of fracture, when present, is pathognomonic for ACL tear?
A. definitive diagnosis of ACL tear
How are cruciate ligament injuries treated?
1. Physical Therapy
A. regain ROM, strengthen quads/hamstrings
B. if pt has instability of joint, refer to Ortho
2. Surgical reconstruction with autograft or allograft (ACL)
A. Pts < 40 yrs
B. Pts who participate in competitive sports
C. Pts with instability when performing daily activities
Which collateral ligament is more commonly injured?
MCL injury > LCL
What is the MOI for a collateral ligament injury?
A. Valgus force w/o rotation, such as football clipping injury
B. Most are able to ambulate following injury
What are the sx of MCL injuries?
1. Medial knee pain
2. Medial swelling
What is a grade I MCL sprain?
pain on valgus stress, no swelling, 0-5 mm jt line opens up
What is a grade II MCL sprain?
What is a grade I MCL sprain?
What is a grade III MCL sprain?
pain and 2-3+ laxity on valgus stress, 10-15 mm and often there is not an end-point
How does the valgus and varus stress tests need to be performed?
Perform valgus stress test at Full Extension AND 30 degrees flexion
What imaging needs to be performed for an MCL injury?
2. MRI to evaluate ligament injury as well as possible meniscus and ACL injury
What is the treatment for MCL injury?
2. +/- Crutches
3. Hinged knee brace
A. Cycling, quads strengthening exercises
What arteries feed the head of the femur?
1. Branch of the obturator artery
2. Lateral femoral circumflex artery
3. Medial femoral circumflex artery
What is the etiology of OCD osteochondritis dissecans?
1. inflammation, ossification abnormalities
2. AVN (usually posterolateral aspect of medial femoral condyle)
How is OCD discovered in adolescents?
discovered incidentally on x-ray or can present with aching and activity-related pain
What are the sxs of OCD?
1. Anterior knee pain that is poorly localized
2. Pain worsens w/ running, stair climbing
3. May be stable OCD or unstable OCD
A. if unstable or loose chondral defect,
mechanical sxs can occur
4. Popping, locking of joint, joint weakness
What dx studies are used to dx OCD?
1. Xray: AP, Notch (tunnel) views
2. MRI to confirm
What is the treatment for OCD?
1. NWB or PWB w/ crutches 3-6 wks or until pain-free!
2. Activity modification needed
3. Repeat x-ray 4 wks & Re-evaluate patient’s sxs and examine
4. Prognosis is generally good for stable OCDs in skeletally immature child
What is the success rate for total knee arthroplasty at 10 years and at 20 years?
95% success @ 10 yrs, 80-85% success @ 20 yrs
When is a total knee arthroplasty indicated?
1. Indicated for severe OA and RA
2. OA is most common form of knee arthritis
3. When conservative modalities have failed:
A. NSAIDs, P.T., cortisone injections, hyaluronic acid injections
What is the most common aspect of the knee to be involved with OA?
1. Medial compartment most commonly involved
A. genu varus
2. Lateral compartment only(less common)
A. genu valgus
What is the treatment for OA if only one compartment is involved?
What are the characteristics of TKA surgery?
1. Length of surgery
A. Varies according to surgeon’s expertise
A. Spinal or GETA
3. Physical Therapy
A. Postop BID
4. WBAT w/ walker for few days to one week -> cane
5. D/C from hospital on post-op day #2 or #3
A. Home PT briefly then outpatient PT
B. Short term rehab becoming less common
What is the recovery period for TKA? What does it involve?
1. Physical Therapy
A. TIW x 2-3 months
2. Most dramatic improvement occurs in first 1-3 months postop
A. Continue to improve for up to one year inc strength and endurance
3. Pre-dental prophylaxis for 2 years or lifetime to dec risk of prosthetic infection
What are the limitations for TKA?
A. No running or pounding activities
2. Low-impact exercising is encouraged
A. swimming, biking, walking
3. Kneeling avoided for several months after surgery and then, repetitive kneeling discouraged even with knee pads
A. 3-6 weeks depending on laterality
What is the pathophys of compartment syndrome?
1. Muscle groups are divided into compartments
A. Formed by strong, unyielding fascial membranes
2. ↑ intracompartmental tissue pressure -> secondary elevation in venous pressure -> venous outflow obstruction
3. Cycle of continued rising pressure -> muscle necrosis and nerve tissue dysfunction w/in 4-6 hrs after onset
What are the etiologies of compartment syndrome?
1. Decr. compartment volume
A. circumferential casting
A. major vascular injury
3. Incr. cap pressure
A. venous obstruction
4. Direct infusion
A. infiltrated IV line, injection gun
5. Incr. cap permeability -> edema
A. ortho sx, burns, direct trauma
What are the general characteristics of compartment syndrome?
1. Compartment syndrome may occur acutely, as in trauma or postop period
2. Exercise-induced compartment syndrome, chronic (in athletes)
3. Acute compartment syndrome is a Surgical Emergency!
What is the mc site of compartment syndrome?
1. Leg (tibia)
A. # 1 site
When is compartment syndrome most likely?
1. Trauma- fracture of long bone or forearm
2. Pts usually < 35 yrs age
3. M > F
What are the 5 P's of compartment syndrome? What are the other sxs?
1. 5 “P’s” assoc w/ compartment syndrome:
A. Pain out of proportion to apparent injury
-Most Common finding
2. Pain aggravated by passive stretch of muscle
3. Tense compartment
A. Firm “wood like” feeling
Describe the pain of compartment syndrome?
1. Exquisite, deep, constant, and poorly localized pain out of proportion with PE findings
2. Numbness, tingling, paresthesias
How is compartment syndrome dxed?
1. Compartment syndrome is a clinical diagnosis, but pressure w/in the muscle compartments can be measured
2. Of the 5 “P”s, only pain & paresthesias are useful for early diagnosis of compartment syndrome
How are the pressures within a compartment measured?
1. Inject small quantity of saline into a closed compartment and measure the resistance from tissue pressure w/ manometer
A. Nl pressure 0-8 mm Hg
B. Capillary flow compromised with pressure 25-30 mm Hg
C. Pain develops when pressure is 20-30 mmHg
How is compartment syndrome treated?
1. Remove all external compression on compartment / extremity
A. i.e. dressing, cast or splint
2. Keep limb at level of heart
5. Surgery- Emergent Fasciotomy
A. Decompresses involved compartment
B. Definitive treatment