MSK Flashcards
What is osteogenesis imperfecta
a group of genetic disorders of collagen metabolism causing bone fragility
What is the most common inheritance pattern in osteogenesis imperfecta
Autosomal dominant
What classification is used categorise osteogenesis imperfecta based on phenotypic severity
Sillence classification
Describe the 4 types of osteogenesis imperfecta based on phenotypic severity
- Type I: mild, non-deforming (fewer fractures, blue sclera)
- Type II: severe perinatal (lethal in infantile period, blue sclera)
- Type III: progressively deforming (multiple fractures, blue sclera)
- Type IV: moderately deforming (multiple fractures, grey or white sclera)
Most cases of osteogenesis imperfecta are caused by mutation in which 2 genes
COL1A1 or COL1A2
Give 5 clinical features of osteogenesis imperfecta
- recurrent fragility fractures following minor trauma
- blue-grey sclera
- hearing loss
- dental abnormalities
Give 3 abnormal facial features that may be seen in osteogenesis imperfecta
- triangle face
- frontal bossing
- broad forehead
How is osteogenesis imperfecta diagnosed
- skeletal survey - reveal fractures and bone deformities
- DXA scan - bone density
- genetic testing
How is osteogenesis imperfecta managed
- MDT: orthopaedics, physio, OT, dentistry etc
- Vit D/ calcium supplements
- bisphosphonates - increase bone density
- lifestyle changes - safe handling techniques, physical activity, avoid smoking/drinking/corticosteroids
What is rickets
deficient mineralisation of the growing bone or osteoid tissue
Give 4 causes of rickets
- Nutritional vitamin D deficiency - inadequate intake or insufficient exposure to direct sun
- calcium deficiency
- hereditary hypophosphataemic rickets - X linked dominant
- drugs
Give 2 examples of vitamin D rich foods
Eggs
Oily fish
What is the main reason for inadequate vitamin D supply in infants from western countries
prolonged breastfeeding without vit D supplementation
Name a drug that can cause rickets
phenytoin (anticonvulsant)
Give 4 RFs of rickets
- Malabsorptive conditions - CF, coeliac, pancreatic insufficiency
- inadequate sun exposure
- breastfeeding
- calcium/ phosphate deficiency
Give 4 ways rickets presents
- bone pain
- poor growth
- bone deformities
- muscle weakness
Give 4 bone deformities that may be seen in rickets
- bow legs - toddlers
- knock knees - older kids
- rachitic rosary - swelling at the costochondral junction
- craniotabes - soft skull bones
- kyphoscoliosis
How is rickets investigated
- XR of knee and wrists - widened epiphyseal plate
Bloods tests: - serum calcium/ phosphate may be low
- LFTs - raised ALP
- Low vitamin D levels
- raised PTH
How is rickets managed
- Vit D (ergocalciferol) and Ca supplementation
- advice on a balanced diet
What is transient synovitis
self-limiting inflammatory disorder of the hip
aka irritable hip
What is the typical age group for transient synovitis?
3 - 10 years old
What are common features of transient synovitis?
- Limp or refusal to weight bear
- Groin or hip pain
- Symptoms usually occur within a few weeks of a viral illness
- positive log roll - leg rolled gently while child lays flat. +ve test = involuntary muscle guarding
- Low-grade fever in a minority of patients
How is transient synovitis managed
- self-limiting, requiring only rest and analgesia
- exclusions of septic arthritis - if child has fever, refer for same-day assessment even if transient synovitis is suspected
What are the most commonly affected joints in septic arthritis?
hip, knee, and ankle.
What are the common causative organisms of septic arthritis in children?
- Staphylococcus aureus
- Neisseria gonorrhoeae (in sexually active teenagers)
- Group A Streptococcus (Strep pyogenes)
- Haemophilus influenzae
- E. coli
What are the signs and symptoms of septic arthritis in children?
- Hot, red, swollen and painful joint
- Limp and reduced range of motion
- Fever
- lethargy
What investigations are performed for septic arthritis
- Joint aspiration for culture (will show raised WBC)
- Raised inflammatory markers
- Blood cultures
What is the management for septic arthritis in children?
- Admission to hospital - prompt treatment can reduce risk of permanent joint damage
- Empirical IV antibiotics followed by specific antibiotics based on sensitivities
- Surgical drainage and washout may be needed
Name and describe the criteria that is used to assess the probability of septic arthritis in children
Kocher criteria:
* fever >38.5 degrees C
* non-weight bearing
* raised ESR
* raised WCC
What is osteomyelitis
Infection of the bone and bone marrow - typically in the metaphysis of the long bones
What bacterias commonly cause osteomyelitis
- Staph. aureus - mc
- Salmonella in sickle cell anaemia
- Pseudomonas aeruginosa (IVDU)
- Aerobic gram -ve bacilli
Give some RFs of osteomyelitis in children
- Males under 10
- Open bone fractures
- Orthopaedic surgery
- Immunocompromised/ HIV
- Sickle cell anaemia
- TB
How does osteomyelitis present in children
- fever
- Refusing to use the limb or weight bear
- Pain
- Swelling
- Tenderness
How is osteomyelitis investigated in children
- X-rays are first line
- MRI are gold standard imaging
- Bloods: raised CRP, ESR and white cells
- Blood cultures - causative organism
- Bone marrow aspiration
How is osteomyelitis managed in children
- flucloxacillin 6w or clindamycin if penicllin allergy
- Surgery may be needed for drainage and debridement of the infected bone
What is Perthes’ disease?
Perthes’ disease is a degenerative condition affecting the hip joints in children
(Legg-calve-perthes disease)
What is the pathophysiology of Perthes’ disease?
avascular necrosis of the femoral head, specifically the femoral epiphysis, due to impaired blood supply, leading to bone infarction. idiopathic cause
What age group is most commonly affected by Perthes’ disease, and which gender is more frequently impacted?
- usually affects children between 4-8 years old
- 5 times more common in boys
What are the features of Perthes’ disease?
- Hip pain that develops progressively over a few weeks
- Limp
- Stiffness
How is Perthes’ disease diagnosed?
- Plain XR - widening of joint space, decreased femoral head size/flattening
- MRI if X-ray is normal and symptoms persist
- Blood test to exclude other causes
What is the management approach for Perthes’ disease?
- To keep the femoral head within the acetabulum: cast, braces
- simple analgesia
- < 6 years: observation
- Surgery for severe cases and older children
What are the complications of Perthes’ disease?
- Osteoarthritis
- Premature fusion of the growth plates
What is slipped upper femoral epiphysis ?
aka slipped capital femoral epiphysis, is a condition where the head of the femur is displaced (“slips”) along the growth plate
What is the typical age range for presentation of slipped upper femoral epiphysis ?
typically presents in children aged 8 to 15 years
Give 2 RFs for slipped upper femoral epiphysis
- obese children
- boys
What are the presenting symptoms of slipped upper femoral epiphysis?
- Hip, groin, thigh, or knee pain
- Restricted range of movement in the hip
- Painful limp
- loss of internal rotation of the hip in flexion
- May present acutely following minor trauma
How is slipped upper femoral epiphysis investigated?
- XR : Anteroposterior and lateral hip XR - will show the femoral head displaced and falling inferolaterally
- inflammatory markers may be used to exclude other causes
How is slipped upper femoral epiphysis managed?
- surgery: internal fixation
- bed rest and non-weight bearing
Give 4 complications of slipped upper femoral epiphysis
- avascular necrosis of the femoral head
- chondrolysis
- osteoarthritis
- leg length discrepancy
What is developmental dysplasia of the hip
a structural abnormality in the hips caused by abnormal development of the fetal bones during pregnancy
How is developmental dysplasia of the hip typically detected?
DDH is often picked up during newborn examinations or later when the child presents with:
* Hip asymmetry
* Reduced range of movement in the hip
* A limp
What are some risk factors for developmental dysplasia of the hip?
- First-degree family history of DDH
- female
- Breech presentation
- oligohydramnios
- birth weight > 5 kg
Which infants require a routine ultrasound examination for developmental dysplasia of the hip?
- First-degree family history of hip problems in early life
- all breech babies at or after 36 weeks gestation, regardless of birth presentation or mode of delivery
- Multiple pregnancy
all infants are screened at both the newborn check and also the six-week baby check for DDH using which two tests?
Barlow and Ortolani tests
What are some positive findings of DDH on the NIPE examination?
- Different leg lengths
- Restricted hip abduction on one side
- Difference in knee level when hips are flexed
- Clunking of the hips during special tests (Ortolani and Barlow tests)
How may missed DDH present in an older child
- Trendelenburg gait
- leg length discrepancy
Describe the Barlow and Ortolani tests
Barlow: attempted dislocation of a newborn’s articulated femoral head
Ortolani test: attempts to relocate a dislocated femoral head
What imaging technique is used to confirm the diagnosis of DDH?
- Ultrasound is generally used to confirm the diagnosis if clinically suspected
- If the infant is > 4.5 months, X-ray is the first-line investigation.
What is the management for developmental dysplasia of the hip
- most unstable hips will spontaneously stabilise by 3-6 weeks of age
- Pavlik harness in children younger than 4-5 months
- older children may require surgery
What is Juvenile idiopathic arthritis
arthritis (without any other cause) occurring in someone who is less than 16 years old that lasts for more than 6 weeks
Name 3 subtypes of Juvenile idiopathic arthritis
- Systemic JIA (still’s disease)
- Polyarticular JIA
- Oligoarticular JIA (pauciarticular) - most common
Give some features of systemic JIA
- Subtle salmon-pink rash
- High swinging fevers
- Enlarged lymph nodes
- weight loss
- Joint inflammation and pain
What are the typical lab findings in systemic JIA?
- Antinuclear antibodies (ANAs) and rheumatoid factors are typically negative.
- raised CRP, ESR, platelets and serum ferritin
What is oligoarticular juvenile idiopathic arthritis
involves arthritis in 4 joints or less and usually affects a single joint (monoarthritis)
How does oligoarticular JIA typically present
- joint pain and swelling: usually medium sized joints e.g. knees, ankles, elbows
- limp
- associated with anterior uveitis
What are the typical laboratory findings in oligoarticular JIA?
- Inflammatory markers are usually normal or mildly elevated
- Antinuclear antibodies (ANAs) are often positive
- rheumatoid factor is usually negative
How is juvenile idiopathic arthritis managed
- NSAIDs, e.g. ibuprofen
- Steroids, either oral, IM or intra-artricular in oligoarthritis
- DMARDs e.g. methotrexate, sulfasalazine and leflunomide
- Biologics, e.g. tumour necrosis factor inhibitors etanercept, infliximab and adalimuma
