see also:

• the child with hip pain - irritable hip vs septic arthritis
• orthopaedics in the ED
• arthritis - clinical patterns

• trauma:
  • fracture
  • occult growth plate trauma - esp. distal fibula
  • haemarthrosis - usually underlying intra-articular fracture
  • non-accidental injuries
• foreign body:
  • esp. feet/knees eg. occult sewing needles, rose thorns (either may be intra-articular!!)
• new shoes, local foot painful lesions (eg. paronychia, bunions, warts, insect bites)
• haemarthrosis due to haemophilia (males)
• septic arthritis
• osteomyelitis (usually in metaphyses of long bones if haematogenous)
• discitis
• tumor - musculoskeletal, spinal, leukaemia, neuroblastoma (infants)
• reactive arthritis: eg. urticaria, erythema multiforme, serum sickness, post-infectious, Henoch-Schonlein purpura (HSP)
• rheumatic fever
• juvenile chronic arthritis
• haemoglobinopathy (eg. sickle cell crisis)
• long-standing, congenital, birth or genetic lesions:
  • cerebral palsy
  • spina bifida
  • cong. dislocation hip
  • muscular dystrophy
  • talipes (eg. Charcot-Marie-Tooth peroneal atrophy)
  • severe scoliosis
• REMEMBER:
  • referred pain from back to hips/thighs & from hip to knees!!!
  • thus examine spine, sacro-iliac joints too!!

• toddler's fracture tibia:
  • often no history of trauma although Hx of tripping over is common
  • usually non-tender but will not weight bear
  • classically only seen on one view of xrays - often faint spiral # mid-tibia
  • Rx AKPOP 3wks if # evident, otherwise consider re-XR in 10 days looking for periosteal reaction
• other commonly missed, common fractures lower limbs:
  • base or necks of 2nd-4th MTs
  • greenstick fractures: femoral shaft, upper tibial metaphysis
  • occult fractures:
    • only evident on XR 10days later & even then only if not growth plate injury
• “irritable hip” / “viral” synovitis hip:
  • see hip pain
  • usually lasts several days
  • pain/spasm on int/ext. rotation of hip
  • Mx:
    • XR hips to exclude other pathology (trauma, early-onset Perthe's, cong. dislocation hip)
    • consider US hips:
      • not usually needed if Dx of irritable hip clinically obvious
      • reserve for cases where hard to localise pain in lower limb
    • FBE, ESR, CRP, BC if suspicion of sepsis (eg. fever, malaise or unwell)
    • if sepsis/trauma excluded then non-wt bear until better, regular review (eg. daily) to watch for evidence of sepsis.
    • consider avoiding analgesics if child is then likely to run around!

• commonly missed, common fractures lower limbs:
  • base or necks of 2nd-4th MTs
  • greenstick fractures: femoral shaft, upper tibial metaphysis
• benign hypermobility syndrome:
  • esp. if recurrent pattern
  • usually 1-4 week cycles of episodic, nocturnal, post-activity, bilateral, ill-defined pain of lower extremities
• Perthe's disease (avascular necrosis femoral head):
  • initially unilateral, early xray changes may be subtle
  • usually 5-9yr olds but may have onset at 3-4yrs age

• slipped femoral epiphysis:
  • extremely important not to miss as needs early internal fixation & non-wt bearing pre-op
  • classically in obese boys 10-15yrs age but can occur in in thin girls 9yrs old!
  • often presents as knee pain!!
• other commonly missed, common fractures lower limbs:
  • base 5th MT (don't confuse with epiphysis which is longitudinal not transverse line)
  • avulsion tibial spines (assume in all adolescents who have acute haemarthrosis knee after falling off bikes or motorbikes, until proven otherwise)
• patello-femoral pain / chondromalacia (esp. in females)
• Osgood-Schlatters disease:
  • over-use osteochondritide of tibial tuberosity
• other osteochondritidies:
  • Scheurmanns
  • Kohler's disease of the navicular
  • Sever's disease calcaneum
  • Frieberg's disease head 2nd MT
  • osteochondritis dessicans medial femoral condyle
• reflex sympathetic dystrophy (RSD) / complex regional pain syndrome / causalgia:
  • often follows minor trauma
  • sweaty, tender, mottled, cold skin
• rarely:
  • Reiter's syndrome
  • Gonococcal arthritis