4. metabolic, congenital, hereditary, and degenerative bone disorders

list the bone disorders covered in this section

scoliosis, non-accidental trauma, osteogenesis imperfecta, advanced/delayed bone age, developmental dysplasia of the hip

define scoliosis

lateral deviation of the spine from the MSP

lateral deviation of the spine more than ___ degrees is classified as scoliosis

20

what does scoliosis do to the ribs + why

body twists = ribs are prominent

scoliosis classification

degenerative, traumatic

scoliosis etiology

80% structural, 20 % non structural (aka functional)

describe structural scoliosis

fixed, fails to correct on recumbent lateral bending studies. there are other structural changes in the bone + nerves + muscles + other tissues

describe non structural scoliosis

is fluid, the curvature corrects with lateral bending

list the types of structural scoliosis

idiopathic, congenital, neuromuscular, radiation induced, trauma, degenerative joint disease, miscellaneous

describe idiopathic structural scoliosis

this makes up 80% of all cases of structural scoliosis; cause is unknown. classified by onset

idiopathic structural scoliosis is classified by onset. list these

infantile, juvenile, adolescent

list some potential factors that may lead to idiopathic structural scoliosis

diet, muscular imbalance, inheritance, connective tissue disease

does idiopathic structural scoliosis affect males or females more

females

describe congenital structural scoliosis

there is a defect in the construction of the VBs, hemi vertebrae is common, ribs may be fused, extra segments may be seen, fused segments may be seen, missing or fused ribs

what does congenital structural scoliosis do to the lungs

interferes with lung growth = problems with breathing

hemi vertebrae is seen in congenital structural scoliosis. describe this

there is a half vertebra wedged between two normal vertebrae = spine curves

congenital structural scoliosis treatment

remove the abnormal segments, spinal fusion

describe treatment for missing/fused ribs in congenital structural scoliosis

titanium rib prosthesis is attached to the upper and lower ribs where there are missing or fused ribs = allows room for heart and lung development

describe neuromuscular structural scoliosis

neuropathic or myopathic disorders may produce a progressive spinal deformity = abnormal function of the muscles/nerves around the spine

give an example of a neuropathy that may lead to neuromuscular structural scoliosis

cerebral palsy, spinal cord trauma

give an example of a myopathy that may lead to neuromuscular structural scoliosis

muscular dystrophy

neuromuscular structural scoliosis age group

11-16

describe radiation induced structural scoliosis

radiation tx during bone group = uneven development of muscles/bones = scoliosis

describe trauma induced structural scoliosis

fractures/dislocations = lateral deviation of the spine due to spinal cord injury

describe degenerative joint disease induced structural scoliosis

destruction of disc/facets = unilateral changes = scoliosis

list 2 miscellaneous causes of structural scoliosis

tumours, surgery

describe non structural scoliosis

no structural alterations like rotation, existing curves are compensatory curves

causes of non structural scoliosis

unequal leg lengths, herniated disc, muscle spasm

is non structural scoliosis reversible or irreversible

reversible

list the complications of scoliosis

cardiopulmonary, degenerative spinal arthritis, curvature progression, radiation exposure, birthing difficulties

one complication of scoliosis is cardiopulmonary complications. describe this

deformed bony thorax puts pressure on the heart and lungs

one complication of scoliosis is curvature progression. describe this

double curve (compensatory) develops, most rapid growth spurts in adolescence

signs and symptoms of scoliosis

lateral curvature of the spine

list 4 reasons why we perform radiography for scoliosis

evaluating curve site + magnitude + flexibility, assessing bone maturity in planning treatment, monitoring curvature progression or regression, aiding in tx planning

how do we evaluate curve site + magnitude + flexibility for scoliosis

cobb method

describe the cobb method for scoliosis

identify the upper and lower end vertebrae, draw lines extending along the vertebral borders, measure the angle

for scoliosis, we do radiography to assess bone maturity in planning treatment. describe why

bone growth should be ceased prior to surgical intervention (we won’t want to do surgery on growing bones)

list the 3 methods of measuring bone maturity for scoliosis

left hand/wrist, VB ring epiphysis, iliac crest

we use the left hand/wrist to measure bone maturity for scoliosis. describe this

the distal radial epiphysis closes at the same time as the VB epiphysis

we use the VB ring epiphysis to measure bone maturity for scoliosis. describe this

fusion of the epiphysis to VB is indicative of spinal maturation

we use the iliac crest to measure bone maturity for scoliosis. describe this

fusion of the iliac crest cap parallels final spinal maturation

list the 3 steps of scoliosis tx

observation, bracing, surgery

describe the observation phase of scoliosis tx

xrays taken every 3 months to monitor it

describe the bracing phase of scoliosis tx

milwaukee braces are used

in what cases of scoliosis are milwaukee braces used

for curves that are flexible, skeletally immature, between 20-40 degrees, progressive in nature

T or F: milwaukee braces are used to correct scoliosis

false

since milwaukee braces are not used to correct scoliosis, what are they used for

to slow progression

describe the surgical phase of scoliosis tx

done when the abnormality can’t be treated, when there is rapid curve progression, curves more than 40 degrees

list the corrective instrumentation that is put in during scoliosis surgery

harrington rods, dwyer screws/wires

list 3 alternative names for non-accidental injury

child abuse, non-accidental trauma, suspected physical abuse

NAI classification

traumatic

NAI etiology

deliberate physical harm to a child

NAI pathogenesis

multiple and complex #s, #s on non ambulatory infants, rare #s, #s that don’t fit the provided hx, multiple injuries over a span of time = various stages of healing

which # types are commonly seen in NAI

ribs (due to squeezing), corners of metaphyses (due to shaking), single fractures of long bones, SP #s, scapular #s, sternal #s

NAI signs and symptoms

pain and swelling of affected areas, bruising over bony prominences, bruises in the shape of a hand, burns, multiple fractures, retinal hemorrhage, mental status changes

what imaging do we do for NAI

head CT, skeletal survey; assesses long bones, thorax, pelvis, and skull

NAI tx

depends on the injury

what is osteogenesis imperfecta

genetic disorder known as brittle bone disease; bones fracture easily due to poor quality or small amount of collagen in their connective tissue

osteogenesis imperfecta classification

hereditary

osteogenesis imperfecta etiology

body doesn’t have enough collagen = weak bones

osteogenesis imperfecta pathogenesis

pt can experience a few to hundreds of fractures over their lifetime. as fractures heal, the callus is large and disproportionate = deformity

osteogenesis imperfecta signs and symptoms

pain, immobility, sclera of the eye is blue, loose joints, muscle weakness

how do we diagnose osteogenesis imperfecta

clinical exam and exclusion of metabolic causes of osteoporosis, dermal biopsy, genomic DNA sequencing

osteogenesis imperfecta radiographic appearance

very osteoporotic bones with thin bony cortices, calluses evident as fractures heal, multiple wormian bones + wide sutures in the skull, short stature

osteogenesis imperfecta treatment

focus is on preventing bony fractures, rods may be inserted to prevent bowing of long bones, meds used to regulate osteoclast formation

osteogenesis imperfecta common prognoses

respiratory failure, accidental trauma

classification of delayed/advanced bone age

congenital, metabolic (endocrine disorders), congenital adrenal hyperplasia

when do we do delayed/advanced bone age investigations

to investigate short/tall stature, early/late puberty, or to predict adult height

advanced bone age etiology

elevated sex steroid levels, endocrine disorders, familial tall stature, childhood obesity

advanced bone age pathogenesis

characterized by accelerated bone maturity (2 years advanced from the child’s chronologic age)

when is advanced bone age of concern

if there are underlying pathologies causing the issue

delayed bone age etiology

endocrine disorders = decreased hormone levels, systemic diseases (heart, urinary, digestive), chromosomal disorders, familial short stature, idiopathic

delayed bone age pathogenesis

characterized by delay of bone growth (2 years behind a child’s chronologic age), delay of growth and puberty

delayed/advanced bone age signs and symptoms

accelerated or slowed skeletal growth. other signs and symptoms would be specific to underlying pathology

how to diagnose delayed/advanced bone age

PA and hand wrist xrays are done of the non dominant hand, rad compares these to preset standards to determine actual bone age

list the order of carpal bone ossification

capitate, hamate, triquetral, lunate, trapezium, trapezoid, pisiform

when does the capitate ossify

1-3 months

when does the hamate ossify

2-4 months

when does the triquetral ossify

2-3 years

when does the lunate ossify

2-4 years

when does the trapezium ossify

4-6 years

when does the trapezoid ossify

4-6 years

when does the pisiform ossify

8-12 years

when does the distal radius ossify

1 year

when does the distal ulna ossify

5-6 years

delayed/advanced bone age treatment

referral to endocrinologist

disc herniation classification

degenerative

DH alternative name

herniated nucleus pulposus

describe DH

displacement of the intervertebral disc material fast the outer fibrous ring

DH can be classified as contained or uncontained. what does this depend on

if the posterior longitudinal ligament is intact or torn

list the 3 types of DH based on appearance

protrusion, extrusion, sequestered

describe protrusion DH

the base is wider than the herniation

describe extrusion DH

the herniation is wider than the base

describe sequestered DH

displaced disc material separates from the disc

who does DH affect

30-50 year olds, common in males

DH etiology

age, genetic/hereditary due to gene polymorphisms, occupational stresses, high BMI, smoking, trauma, connective tissue disorders

where on the spine is DH common

L4/5, L5/S1, C6/7

signs and symptoms of DH

can have loss of bowel/bladder control, low back pain, pinched nerve symptoms

how to test for DH in a physical exam

positive lasegue sign: ipsilateral leg pain when raising straight leg of supine pt

modality for DH

MRI is gold standard