Orthopedics

Question 1

what is developmental dysplasia of the hip

Answer 1

abnormal growth of hip resulting in instability and dislcation, common in oligohydramnios, breech, female sex, first born children, LGA

Question 2

Examination of DDH

Answer 2

Ortolani and barlow done at 1 day, assymetry

Question 3

inspection DDH

Answer 3

LACK OF LABRAL FOLDS, REDUCED MOVEMENT OF LEGS, decreased abduction on the affected side, standing or walking with external rotation

Question 4

Management of DDH

Answer 4

pavlik harnus abduction splints until 5-6 months, surgical correction in late diagnosis

Question 5

complications of DDH

Answer 5

osteoarthritis, avascular necrosis

Question 6

What is the definition of duchenne and beckers dystrophy

Answer 6

x linked recessive degenerative muscle disorders
DMD is rapid
BMD is slow

Question 7

what mutation is DMD

Answer 7

in dystrophin gene

Question 8

What is the history of DMD

Answer 8

DMD: Healthy at birth. At 6 years, progressive weakness, abnormal gait, toe walking, difficulty getting up. By 10, require braces to walk. By 12, wheelchair bound. LD in 20%. §

Question 9

What is the history of BMD

Answer 9

Symptoms begin at around 10y, milder version than DMD.

Question 10

at what age does DMD usually present

Answer 10

6 years

Question 11

examination dmd

Answer 11

Weakness distribution: symmetrical, especially in pelvic and shoulder girdle muscles.
Calf muscle pseudohypertrophy: Excess adipose replacement of muscle fibres.
Gower’s sign: Child pushes hands on thigh to overcome weakness

Question 12

what is the gold standard diagnostic test for dmd

Answer 12

genetic testing

Question 13

what other tests can you do for DMD

Answer 13

Bloods: high CK. EMG to exclude neurogenic weakness.
Genetic testing is diagnostic
Muscle biopsy to stain for dystrophin to assess amount.
LFT: low vital capacity, due to low muscle strength.

Question 14

management of DMD

Answer 14

• Medical: oral corticosteroids improve strength, early aggressive management of cardiomyopathy, respiratory assessments, immunisations + pneumococcal and flu. Prophylactic antibiotics if very low VC.
• Orthopaedic: contracture correct, scoliosis repair, scapular fixation.
• OT/PT/education/genetic counselling for CVS/psychological.

Question 15

What is achondrodysplasia

Answer 15

o Achondroplasia: AD condition involving mutation in FGFR3 gene on CHr4. 50% de novo. Increased FGFR3 gene (has a negative regulatory effect on bone growth) function leading to reduced endochondrial ossification leading to short legs and normal torso length (dwarfism)

Question 16

what is osteodysplasia

Answer 16

o Osteogenesis imperfecta: AD mutation for Type I collagen. Substitution of glycine residues in the normal glycine-X-Y alternation sequence.

Question 17

what are the 4 types of OI

Answer 17

• Type I recurrent fractures and blue sclera, early deafness.
• Type II: most severe, may be stillborn or die in infancy from respiratory insufficiency. Fragile, low BW, small thorax.
• Type III: in utero fractures, macrocephaly, triangular facies, scoliosis.
• Type IV: moderate short stature, bowing of legs, often mobile

Question 18

Investigations OI

Answer 18

• DEXA: BMD<75% normal
• Lumbar SXR: for compression from fractures.
• Collagen synthesis analysis

Question 19

MANAGEMENT oi

Answer 19

: prompt fracture splinting or casting to restore function, physiotherapy in young children, mobility aid.

Question 20

What is juvenile idiopathic arthritis/stills disease

Answer 20

Group of chronic arthropathies in childhood. Seven ILAR subtypes:

1. Systemic: sJIA: >1j, preceded by fever>3d with rash, lymphadenopathy etc.
2. Oligoarticular : <4 joints, may be persistent or extended.
3. Polyarticular, RF negative
4. Polyarticular, RF positive
5. Enthesitis-related arthritis ERA: arthritis and enthesitis, sacroiliac/lumbosacral pain, HLAB27, male>6y, acure anterior uveitis, Reiter syndrome (reactive arthritis following GI or STI infection)
6. Psoriatic arthritis: With psoriasis
7. Undifferentiated: No category or more than 2 of the above

Question 21

what is the aetiology of JIA/stills disease

Answer 21

o Aberrant immune or inflammatory response leading to T cell activation, humoral immunity or innate immunity initiation. HAL subtypes linked to risk.
o DDx: Bacterial/viral infection, malignancy, vasculitis, CT disease. Septic arthritis if single joint.

Question 22

History of JIA

Answer 22

o General: acute joint swelling, pain, warm, stiff, worse AM, improve with activity, reduce range of movement, contractures.
o sJIA, symmetrical, polyarticular, myalgia, abdominal pain, fever, rash.

Question 23

INVESTIGATIONS JIA

Answer 23

FBC, markers of inflammation ESR CRP ferritin. RF, ANA, HLA subtype, slit lamp exam (anterior uveitis) XR, USS, MRI.

Question 24

complications jia

Answer 24

Anterior uveitis is asymptomatic, failure to screen this may lead to glaucoma, cataracts and blidness. THEREFORE DO SLIT LAMP EXAM!!!!

Question 25

Definition legg calve perthes disease

Answer 25

Idiopathic avascular necrosis of the capital femoral epiphysis of the femoral head.

Question 26

aetiology legg calve perthes disease

Answer 26

o General: unknown, probably multifactorial. 25% bilateral (doe not occur at same time). May be due to altered growth pattern, trauma, and fibrinolysis defects like sickle cell crisis. Rapide epyphiseal growth and lack of supply keeping up. o Classification: Modified Elizabethtown – I sclerotic (withor without loss of height), II fragmentation (A early B late), III healing (A peripheral, B medial 1/3), IV healed. o Associated with sickle cell, premature, SES low, low BW, high parental age, passive smoking.

Question 27

is legg calve perthes disease painless or painful

Answer 27

calssically painless

Question 28

symptoms of legg calve pethes

Answer 28

Limp: early sign, intermittent, abductor lurch, post exercise. Painles slimp. Pain: classically painless, may have mild intermittent pain in anterior thigh or hip pain secondary to necrosis of affected bone, referred to medial aspect of ipsilateral knee or thigh.

Question 29

signs legg calve perthes

Answer 29

o Look: atrophy of the quad due to disuse. Leg length inequality, hip adduction flexion deformity, Trendelburg gait. o Feel: nil o Move: restricted ROM, mostly internal rotation and abduction. global rROM in late. o Roll test: supine position, roll foot on internal and external rotation. Guarding or spasm with internal rotation. o At risk femoral head signs: high age, high weight, loss of movement, adduction contracture, flexion with adduction.

Question 30

management of legg calve perthes

Answer 30

Containment theory: secure injured femoral head within socket and movement continued. Conservative: only in healing stage >8yo. Surgical: to achieve containment and salvage the joint, proximal femoral osteotomies, acetabular surgery, abduction osteotomies and chictomy.

Question 31

septic arthritis microbes

Answer 31

Most common Staph Areus, less Strep pyogenes, pneumoniae, E coli etc. Any joint.

Question 32

transient synovitis

Answer 32

Unknown aetiology, unilateral presentaiton, preceding viral infection especially URTI, ligamentous or minor capsular trauma. Viral aetiology suspected if high serum IFN levels and history.

Question 33

koscher criteria

Answer 33

Kocher criteria: four predictors: hx of fever, non weight bearing, ESR>40, WCC>12k. Predicts chance of septic arthritis – presence of 1 is 3%, 2 is 40%, 3 is 93%.

Question 34

aetiology marfans

Answer 34

Commonest cause is FBN1 mutation in 15q21. Occasionally in TGFBR1/2 in Chr9/3. Wide spectrum of mutations, and wide spectrum in clinical presentation. Due to highly fraying microfibrils. Microfibrin is a substrate for elastin and component of CTs.

Question 35

history/exam marfans

Answer 35

o Tall thin individual with low UB:LB ratio and long thin arms and legs. o MSK: Muscle hypotonia, hyperextendable lax joints, delayed motor milestones, frequent disoacitons, arachnodactyly, scoliosis, kyphosis, pectus excavatum/planus. o Poor or loss of vision (upward lens detachment) retinal detachment. o CVS: aortic root dilation, aortic dissection, AR (EDM), MR /MVP (PSM with click), arrhythmias. o Respiratory: PTX o Derm: striae atrophicae on back and arms.

Question 36

osgood -schlatter aetiology

Answer 36

o Mostly traumatic, usually occurs in the year following a growth spurt. o Tension from the insertion of the quadriceps muscle into the tibial apophysis leads to a partial avulsion fracture in the ossification centre. This leads to sclerosis of the apophyseal bone around the insertion, leading to a visible lump. o Usually occurs in athletes, especially impact ones (i.e. running jumping). o DDX: tibial fracture, underlying tumor, quadriceps tendon avulsion. Chondromalacia patellae, osteomyelitis, patellar tendonitis.

Question 37

examination osgood schlatter

Answer 37

o Mostly traumatic, usually occurs in the year following a growth spurt. o Tension from the insertion of the quadriceps muscle into the tibial apophysis leads to a partial avulsion fracture in the ossification centre. This leads to sclerosis of the apophyseal bone around the insertion, leading to a visible lump. o Usually occurs in athletes, especially impact ones (i.e. running jumping). o DDX: tibial fracture, underlying tumor, quadriceps tendon avulsion. Chondromalacia patellae, osteomyelitis, patellar tendonitis.

Question 38

management osgood schlatter

Answer 38

Rest: avoid activity. Pain management with NSAIDS. Leg strap or knee immobiliser. Removal surgically of separate ossicle rarely required and only to be done in adults.

Question 39

history/exam vit d deficiency

Answer 39

o Irritability and generalised seizures (hypocalcaemia) o Poor growth, delayed dentition, poor motor development. o Bowed legs, knock knees, swollen chostochrondral junction, thickened wrists, frontal bossing, pathological fractures. o In adolescents, carpopedal spasms.