7 bones and joints

Question 1

causes of genu varum (bowleg)

Answer 1

metabolic bone disease,
asymmetric growth arrest,
bone dysplasia and congenital and neuromuscular disorder

Question 2

causes of genu valgum (knock knees)

Answer 2

metabolic bone disease, 
skeletal dysplasia, 
posttraumatic physeal arrest, 
tumors, 
infection

Question 3

pain over the tibial tubercle in a growing child

Answer 3

Osgood-Schlatter Disease

• traction apophysitis of the tibial tubercle growth plate and the adjacent patellar tendon
• more common in males, athletes, 10-15 years old

Question 4

abnormal morphology and development of the acetabulum

Answer 4

Acetabular dysplasia

Question 5

partial contact between the femoral head and acetabulum

Answer 5

Hip sublaxation

Question 6

hip with no contact between the articulating surfaces of the hip

Answer 6

Hip dislocation

Question 7

-assess potential for dislocation of the non-displaced hip
-adducts Flexed hip and gently pushes the thigh
posteriorly in an effort to dislocate the femoral head
-(+) test: hip will slide out of the acetabulum

Answer 7

Barlow provocative maneuver

Question 8

-attempt to reduce a dislocated hip
-grasp thigh between the thumb and Index finger and
with the 4th and 5th fingers, lift the greater trochanter
while simultaneously abducting the hip
-(+) test: femoral head will slip Into the socket with

Answer 8

Ortolani test (Reverse of Barlow)

Question 9

• femoral head disorder of unkown etiology
• temporary interruption of the blood supply to the
  bony nucleus of the proximal femoral epiphysis,
  leading to impairment of the epiphyseal growth and femoral head deformity

Answer 9

Legg Calve Perthes Disease

-delayed skeletal maturation, shorter than normal
-most common symptom: limp of varying duration
-pain is activity related, localized
-antalgic galt after strenuous activity
-limited hip motion, atrophy of thigh muscles, calf,
buttocks secondary to pain
-classic portrait: small, thin, extremely active child
-plain radiographs: primary imaging tool

Goal of treatment:
create a spherical, well covered femoral head with hip range of motion close to normal

Question 10

most common organism in all age groups of osteomyelitis

Answer 10

S.aureus

Question 11

most common organism in 6y/o osteomyelitis

Answer 11

most cases are caused by S. aureus, Streptococcus, or Pseudomonas aeruginosa

Question 12

second most common cause of osteomyelitis in children

Answer 12

Kingella kingae

Question 13

Diagnostics used for Osteomyelitis

Answer 13

• Blood culture
• history and physical findings
• Aspiration for Gram stain
• Culture: confirms the diagnosis
• Aspiration of bone pus: best specimen
• elevated ESR and CRP: assess response to therapy or identify complications

Question 14

treatment for osteomyelitis in neonates

Answer 14

• Antistaphylococcal Penicillin
  :Nafcillin or Oxacillin (150-200 mkd q6) and
  Cefotaxime (150-200 mkd q8)
  MRSA: Vancomycin and aminoglycoside

Question 15

treatment of osteomyelitis in older children

Answer 15

• Cefazolin (100-150mkd q6) or nafcillin (150-200mkd q6)

- Cefotaxime or Ceftriaxone if no H. Influenza vaccine

Question 16

• have the potential to cause permanent disability
• frequency is increased in infants and toddlers
• Staphylococcus aureus Infection is most common
• Gonococcus in Sexually active adolescents
• 50% occur by 2 y/o, % of cases in 5 y/o
• majority of infections in otherwise healthy children are of hematogenous origin
• can follow penetrating injuries

Answer 16

Suppurative Arthritis/Septic Arthritis

Question 17

diagnostics for suppurative arthritis

Answer 17

• Blood culture
• Gram stain and culture definitive diagnostic technique
• Elevated ESR and CRP
• Plain films: widening of the Joint capsule, soft tissue edema, and obliteration of normal fat lines
• Ultrasonography: highly sensitive in detection of joint effusion, particularly for the hip joint (aid in aspiration)
• CT and MRI; useful in confirming presence of joint fluid

Question 18

treatment for suppurative arthritis

Answer 18

• Neonates: nafcillin or oxacillin and cefotaxime
• Children: cefazolin or nafcillin
• MRSA: Clindamycin and vancomycin
• Immunocompromised: vancomycin and ceftazidime or
• extended-spectrum penicillins and B-lactamase inhibitors
• with an aminoglycoside
• Dexamethasone for 4 days
• Daily aspiration of synovial fluid: Joints
• Surgical emergency: hip

Question 19

achondroplasia

Answer 19

• prototype of chondrodysplasia
• at birth: short limbs, long narrow trunk, large head with midfacial hypoplasia and prominent forehead
• limb shortening: greatest in the proximal segments, and the fingers often display a trident configuration
• Most joints are hyperextensible, but extension is restricted at the elbow
• an autosomal dominant trait
• delayed motor milestones, normal intelligence,
  exaggerated lumbar lordosis
• Infants and children: progressively fall below normal standards for length and height, large heads

Question 20

• large calvarial bones
• small cranial base & facial bones
• short vertebral pedicles, decrease interpedicular
  distance, 1st to the 5 lumbar vertebra
• fibula is disproportionately long compared with tibia
• Surgical correction for severe spinal canal stenosis

Answer 20

Achondroplasia

Question 21

• most common genetic cause of osteoporosis

Answer 21

Osteogenesis Imperfecta (brittle bone disease)

• generalized disorder of connective tissue
  • structural or quantitative defects in type I collagen
  (primary component of the extracellular matrix of bone and skin)
• autosomal dominant

Question 22

TRIAD of Osteogenesis imperfecta

Answer 22

fragile bones
blue sclerae
early deafness

Question 23

• autosomal dominantly inherited disorder
• abnormal biosynthesis of fibrillin-1 (major constituent of microfibrils provide scaffolding network of elastin and have an anchoring function in nonelastic tissue- aortic adventitae & eye’s suspensory ligament)

Answer 23

Marfan Syndrome