MSK Flashcards
What is the genetic pattern of the genetic mutations that are associated with osteogenesis imperfecta (and what % have this)?
90%
Type 1 collagen genes - COL1A1 and COL1A2
Dominant mutation
What is osteogenesis imperfecta?
Brittle bone syndrome where the brittle bones are prone to fractures
What is the key sign to look out for in a child with suspected osteogenesis imperfecta?
Recurrent unexplained fractures (where you are considering safeguarding) and have GREY/BLUE sclera
Other than blue sclera how may a child with osteogenesis imperfecta present?
Hypermobility
Triangular face and short stature
Bone deformities with bowed legs and scoliosis
How may the most severe present during pregnancy?
Most severe forms prenatal diagnosis: 2nd trimester by USS
How may osteogenesis imperfecta present after birth?
X-Ray, bone densitometry and genetic testing after birth.
How may osteogenesis imperfecta be managed (two medication given)?
Bisphosphates: increase bone density
Vitamin D supplements: prevent deficiency
What is transient synovitis?
Irritable hip caused by transient irritation and inflammation in the synovial joint membrane (associated with recent viral URTI)
How does transient synovitis tend to present?
Within few weeks of viral illness.
Acute/more gradual onset of limb, refusal to weight bear, groin/hip pain, mild-low grade fever
The presence of what will prompt transient synovitis to be treated as septic arthritis?
The presence of a fever
How should transient synovitis be managed?
Treat symptoms with simple analgesia prior to symptom resolution which should take 1-2 wks. If fever then treat like septic arthritis
What is the recurrence rate of transient synovitis?
Around 20%
What is rickets?
Defective bone mineralization causing soft and deformed bones
What can rickets progress to in adults if left untreated?
Can progress to causing osteomalacia in adults
What is rickets a deficiency in?
Vitamin D or Calcium
What is rickets secondary to?
- Gastrointestinal malabsorption - consider causes
- Liver disease
- Renal disease
- Drugs: anticonvulsants, rifampicin, HAART
- Severe dietary calcium deficiency
What can cause GI malabsorption which can contribute to rickets in a paediatric patient?
- Surgery
- Cystic fibrosis
- Chronic pancreatic disease
- Crohn’s
- Biliary disease
- Coeliac disease
What is the genetic pattern of hereditary hypophosphatemia rickets?
X-linked dominant disorder
Describe the pathophysiological mechanism causing rickets to be worsened?
- Inadequate vit D
- Lack of calcium and phosphate in blood
- Low levels result in defective bone mineralization
- Secondary hyper-PTH as parathyroid gland secretes PTH to raise calcium levels
- Stimulates increased reabsorption of calcium from bones
- Further bone mineralization problems
How will rickets present?
Bone deformity
Lethargy
Bone pain, swollen wrist
Poor growth and muscle weakness
Dental problems
Patho and abnormal fractures
What level of serum 25-hydroxyvitamin D in rickets patients is required to diagnose vitamin D deficiency?
<25 nmol/L
What will be observed on blood serum in a rickets patient?
Low serum calcium, phosphate
High PTH, serum alkaline phosphate
What is required for rickets diagnosis?
X-ray
What is given as a management for rickets?
Supplement 10 micrograms per day of calcium
Ergocalciferol vitamin D for vitamin deficiency
Which age of children is septic arthritis seen most often in?
<4 years old
What are the symptoms of paediatric septic arthritis?
Hot, red, swollen, painful joint
Hip and knee = third of cases
Refusal to weight bear
Stiffness and reduced range of motion
Systemic symptoms - fever, lethargy, sepsis
Name bacterial causes of septic arthritis?
Staphylococcus aureus
Neisseria gonorrhoea (especially sexually active teens)
GAS
HiB
Escherichia coli
What are the key differential diagnoses to consider?
- Transient synovitis
- Perthes disease
- Slipped upper femoral epiphysis
- Juvenile idiopathic arthritis
What is the gold standard of septic arthritis?
Joint aspiration
What medication is given to patients with septic arthritis?
Flucloxacillin and vancomycin (MRSA)
What is given as an alternative to flucloxacillin should one have a penicillin allergy?
Clindamycin
What is the cause of Perthes disease and location?
Epiphysis of femur
Disruption of blood flow to the femoral head causing avascular necrosis of bone
What age range will Perthes disease effect predominantly?
Children ages 4-12 and is more common in boys
How does the pathological process of Perthes disease present and worsen?
- Revascularization or neovascularization of femoral head over time
- Bone remodeling as it heals
- Complication: soft and deformed femoral head
What does Perthes disease lead to (or at high risk of)?
Early hip osteoarthritis and need for artificial hip replacement
What is it key to look out for in a child with Perthes disease?
NO HISTORY OF TRAUMA
Pain in hip or groin, limp, restricted hip movement, referred pain to knee
What are the investigations for Perthes disease?
X-Ray
Blood tests - particular inflammatory markers
Technetium bone scan
MRI scan
What are the management options for Perthes disease?
Initially conservative with physio and X-ray to assess healing
Then surgery (improve alignment + fn of femoral head and hip) if not successful.
A patient has suffered displacement of the femoral head which slips along the growth plate. What is the diagnosis and who is it more common within?
Boys 8-15 (generally 12 average). Obese.
Slipped upper femoral epiphysis
What is the typical clinical presentation of slipped upper femoral epiphysis?
12 year old adolescent obese male who has slipped and bashed his hip. He’s recently undergone a growth spurt.
How is slipped upper femoral epiphysis diagnosed?
X-ray
Blood test - inflammatory markers
Technetium bone scan
CT/MRI
What is the management for slipped upper femoral epiphysis?
Surgery - return femoral head to the correct position
What is the clinical presentation of a patient with osteomyelitis?
Afebrile with a low-grade fever with pain, swelling and tenderness in their joint which they are refusing to weight bear on.
Which bones does osteomyelitis typically affect?
Long bones
What are risk factors for osteomyelitis?
- Open fracture
- <10 years old
- Orthopaedic surgery
- IC, TB, HIV
- Sickle cell anaemia
What should signify with reference to osteomyelitis that it should be escalated to septic arthritis?
Fever may be high and this is often the case in acute osteomyelitis
What is the management for osteomyelitis?
Antibiotics and surgery to drain and debride the infected bone
What is osgood-schlatter’s disease?
Inflammation at the tibial tuberosity where the patella ligament inserts
What is the pattern of Osgood-Schlatter’s disease?
Usually unilateral
What is the pathophysiological process of the symptoms of Osgood-Schlatter’s disease?
- Patella point insertion into the tibial tuberosity at the epiphyseal plate
- Growth, run/jump/moving results in inflammation
- Multiple small avulsions fractures where patella ligament pulls away pieces of bone
- Growth on tibial tuberosity
- Visible lump below knee
- Tender, but RICE
Which fractures is Osgood-Schlatter’s disease?
Small avulsion fractures
What is the management plan for Osgood Schlatter’s disease?
RICE, NSAIDs
Stretch quads and physiotherapy to strengthen joint
What is a rare complication of OSD?
Full avulsion fracture of the joint (complete separation of the tibial tuberosity)
What is developmental dysplasia of the hip?
Structural abnormality in the hip causing abnormal development of the fetal bones during pregnancy
–> potential for subluxation or dislocation
What are the two tests for developmental dysplasia of the hip which would indicate potential positive or negative test?
Ortolani test
Barlow test
What is seen on the Ortolani test and Barlow test in developmental dysplasia of the hip?
Ortolani test: pressure used to to abduct hips and pressure behind legs with fingers to see if hip dislocates anteriorly
Barlow test: gentle downward pressure on knees through femur to see if femoral head dislocates posteriorly
What are risk factors for developmental dysplasia of the hip?
- 1st degree FH
- Breech presentation from 36wks onwards
- Breech presentation at birth if 28wks onwards
- Multiple pregnancy
Is there screening for developmental hip dysplasia?
Yes at 6-8wks as part of the NIPE: one should look for symmetry in hips, leg length, skin folds, hip movements
What is the diagnosis for developmental dysplasia of the hip?
USS
X-Ray in older infants
Management for developmental dysplasia of the hip?
Pavlik harness if <6 months for 6-8wks
Surgery if >6 months old - hip spica cast to immobilize hip for prolonged period
What is juvenile idiopathic arthritis?
Autoimmune inflammation occurring in the joints with joint pain, swelling and stiffness
Diagnosis for JIA if what?
Arthritis without cause lasting for >6 months in patient <16 years old.
What are the key tell-tale symptoms of systemic JIA (Still’s disease)?
Subtle salmon-pink rash, fever, joint pain with enlarged lymph nodes.
Splenomegaly with muscle pain.
What will be found should investigations be performed for systemic JIA (Still’s disease)?
- Antinuclear antibodies, RF typically negative
- Raised inflammatory markers - raised CRP, ESR, platelets, serum ferritin
What is a key complication of systemic JIA?
Macrophage activation syndrome (MAS): DIC, anaemia, thrombocytopenia, bleed, non-blanching rash, low ESR
What characterizes macrophage activation syndrome?
DIC, anemia, thrombocytopenia, bleed, non-blanching rash, low ESR
What is polyarticular JIA?
Idiopathic inflammation in 5 or more joints
What is the pattern of polyarticular JIA?
Symmetrical affecting 5 or more joints:
- Small joints of hands and feet
and
- Large joints of hips and knees
What are the Sx of polyarticular JIA?
Mild fever, anaemia, reduced growth
What will be found on serum Ix for polyarticular JIA?
Tend to be negative for RF
If seropositive then disease pattern similar to RF
What is the pattern of oligoarticular JIA?
4 joints or less, usually monoarthritis in larger joints - knees and ankles
Who are affected and what age in oligoarticular JIA?
Girls <6 years old.
What is a key characteristic symptom of oligoarticular JIA?
Anterior uveitis
What is seen on serum for oligoarticular JIA?
Antinuclear antibodies often positive
RF usually negative
Enthesitis-related arthritis affects who primarily?
Males over 6 years old
What is found on investigation for enthesis-related arthritis?
MRI scan. HLA-B27 gene
What are the associated symptoms of enthesitis-related arthritis?
Psoriasis, IBD symptoms (diarrhoea and rectal bleeding), anterior uveitis
Which joints may elicit tenderness of entheses?
Interphalangeal joints of the hand and wrist
Greater trochanter of the lateral aspect of the hip
Quad insertion at ASIS
Base of Achilles at calcaneus
What is the pattern of juvenile psoriatic arthritis?
Symmetrical small joins and asymmetrical larger joints
What will be seen on examination in a patient with juvenile psoriatic arthritis?
Pitting, onycholysis, dactylitis, enthesis, psoriatic plaques
What DMARDs can be given to children to treat arthritis?
Methotrexate, sulfasalazine, leflunomide
What biologics can be given to a patient with arthritis?
Tumour necrosis factor inhibitor: etanercept, infliximab and adalimumab
What is Henoch-Schonlein Purpura?
IgA vasculitis presenting with purpuric rash affecting the lower limbs and buttocks in children
What are the four classic features of Henoch-Schoenlein Purpura?
- Purpura - legs and spreads to buttocks
- Arthralgia/arthritis - knees/ankles: reduced ROM
- Abdominal pain - can lead to GI haemorrhage, intussusception, bowel infection
- IgA nephritis: macroscopic or microscopic hematuria and proteinuria
What must be satisfied from the EULAR/PRINTO/PRES criteria for Henoch-Schonlein Purpura to be diagnosed?
Must have palpable purpura and at least one of:
1. Diffuse abdominal pain
2. Arthritis or arthralgia
3. IgA deposits on histology
4. Proteinuria or haematuria
What is the management of HSP?
Supportive - analgesia, rest, hydrate
Monitor - urine dipstick (renal involvement - proteinuria, haematuria), BP (HTN)
