CASE 1

An 11 year old athletic girl presented to this hospital with a 10 week history of increasing pain in her right leg. She had first seen her general practitioner with pain over the tibial tubercle of her right knee but no history of trauma. Her local orthopaedic service had diagnosed Osgood-Schlatter's disease and she had been advised to rest and use crepe bandage and elasticated tubular bandage.

Five days later her leg became cold and blue below the knee, with burning pain radiating from the knee to the foot. Deep vein thrombosis was diagnosed and she was treated with anticoagulant drugs. After a week anticoagulant treatment was stopped, but the leg continued to be painful, cold, and blue when in a dependent position. A full length plaster of Paris cast was applied in an attempt to relieve the pain of the Osgood-Schlatter's disease, but within days the symptoms were worse, affecting her whole leg up to mid-thigh. The blueness resolved only when her leg was elevated. The plaster of Paris was removed, but by this stage the pain was so severe that she would not put her foot on the ground and she was confined to a wheelchair.

On first examination at this hospital the leg was noted to be cold and blue and the foot oedematous. She had allodynia (pain provoked by a stimulus that does not normally cause pain) and hyperaesthesia up to her …