Differentials and Lists from BoneSchool

Question 1

Causes of Charcot Joints

Answer 1

SAD SLIPS

Spina Bifida
Alcohol
Diabetes
Syphilis (tabes dorsalis)
Leprosy (upper limb)
Indifference to pain
Peripheral nerve lesions
Syringomyelia (20% - 40%. No 1 reason in upper limb)

Question 2

Causes of Chondrocalcinosis

Answer 2

WHIPP AA DOG

Wilson's disease
Haemochromatosis
Idiopathic
Pseudogout
Pernicious anaemia
Amyloid
Acromegaly
Diabetes
Ochronosis (homogentisic acid accumulation)
Gout

Question 3

Types of Gait

Answer 3

STRAWS

Short
Trendelenberg
Rigid
Antalgic
Weak
Spastic

Question 4

Causes of Hypercalcaemia

Answer 4

Hyperparathyroidism (primary or secondary)
Malignancy (PTH like proteins)
Vit D intoxication
Sarcoidosis
Milk Alkali syndrome

Question 5

Soft tissue calcification causes

Answer 5

Hypercalcaemia
Myositis ossificans
Haematoma
Trauma
Burns
Tumoral calcinosis
Atherosclerosis
Synovial sarcoma
Chondrosarcoma
Haemangioma
Dermatomyositis
TB
Scleroderma

Question 6

Causes of Avascular Necrosis

Answer 6

AS IT GgRrIPpSss CCC

Alcohol
Steroids

Idiopathic
Trauma

Gaucher's
Gout
Radiation
Rheumatoid
Infection
Pancreatitis
Pregnancy
Smoking
SLE
Sickle cell

Caisson’s
Chemo
CRF

Question 7

Neuromuscular causes of Cavovarus Feet

Answer 7

Brain
Spinal
Anterior horn
Peripheral nerves
Muscle

Brain:

• Primary cerebellar disease
• Cerebral palsy
• Hydrocephalus
• CVA

Spine:

• Freidreich’s ataxia
• Spina bifida / dysraphism
• Diastomatomyelia
• Syringomyelia
• Tumor
• CMT type 2 (axons)

Anterior horn:

• Polio
• SMA

Peripheral nerves:

• CMT type 1 (myelin)
• Polyneuritis

Muscle:
- Muscular dystrophy

Question 8

Non-neuromuscular causes of Cavovarus feet

Answer 8

Clubfoot
Arthrogryposis
Compartment syndrome
Crush
Burn
Malunion
OA / RA

Question 9

Causes of Hallux Valgus

Answer 9

Shoes
Laxity
Metatarsus primus varus
TMT hypermobility
Amputation (of 2nd toe)
Rheumatoid
Achilles tightness
Valgus knee
Neurological
Flatfoot

Question 10

Causes of Intra-articular Loose Body

Answer 10

SOAP

Synovial chondromatosis
OCD
Arthritis
PVNS

Other:
Fracture
Meniscus
ACL stump

Question 11

Causes / Conditions of Ligamentous laxity

Answer 11

DIAL HOME CS

Down Syndrome
Idiopathic
Achondroplasia
Larsen's Syndrome
Homocystinuria
Osteogenesis Imperfecta
Marfan's
Ehler's Danlos
Congenital contractural arachnodactyly
Stickler's Syndrome

Question 12

Causes of Pes Planus

Answer 12

Physiologic
Plantar fascia rupture
Ligamentous laxity
Tarsal coalition
Tibialis posterior tendon dysfunction
CVT
Charcot
Spring ligament rupture
Fracture
Neuromuscular

Question 13

Secondary causes of Protrusio

Answer 13

PROF SHAMN

Paget's
Rheumatoid
Osteomalacia / OI
Fracture
Septic arthritis
Hemiarthroplasty
Ankylosing spondylitis
Marfan's
Neurofibromatosis

Primary cause is Otto Pelvis

Question 14

Bloods to order in Rickets

Answer 14

Ca (high in Hypophosphatasia, low in the rest)
Phosphate (high in Hypophos and renal osteodystrophy, low in the rest)
Alk Phos (low in hypophosphatasia, high in the rest)
PTH (high in most)
Vit D (low in deficient, normal on the rest)
1,25 VitD (low in Dependant type 1, high in dependant type 2)

Question 15

Diagnostic criteria for Rheumatoid (MAX RENS)

Answer 15

From 1987 American College of Rheumatology

Morning Stiffness
Arthritis of 3 areas (> 6/52)
X-ray changes
Rheumatoid factor
Arthritis of the Hand (> 6/52)
Nodules
Symmetric arthritis (> 6/52)