Adolescents, longbones, probably 1% of all osteomyelitis. ?mech – biopsies usually negative on culture! Pain, ?arthritis if adjacent to focus. Associated with:

• pyoderma gangrenosum
• uveitis
• palmar plantar pustulosis (as in psoriasis)
• IBD (may come later)

ie inflammatory, autoimmune sounding. Osteolytic & sclerotic lesions on XR, hotspots on bone scan. Histology not characteristic. Differential diagnosis is Langerhans cell histiocytosis.

Rx NSAIDs, steroids if severe/recurrent, ?pamidronate, ?infliximab.

Self limiting but relapsing over 2-4 yrs. 1 case series showed high rate of deformity, but the largest found no long term complications at all!