Dysbaric Osteonecrosis: Introduction

Aseptic necrosis of bone has been described in diving lizards (mosasaurs) of the cretaceous period, although the association with human diving may not be entirely germane. In humans, infarction of areas of bone associated with exposure to pressure has been recognized since the turn of the twentieth century. The condition has been reviewed most recently in 20141. Twynam first suggested a causal relationship between bone necrosis and pressure exposure in 1888 in a case report of a caisson worker constructing the Iron Cove Bridge in Sydney, although in retrospect the man appeared to have ‘septic’ necrosis.

In 1912, there were 500 cases of decompression sickness (DCS) reported among the caisson workers on the Elbe tunnel at Hamburg, and 9 had bone changes. Bassoe, in 1913, suggested a relationship between initial joint ‘bends’ and subsequent x-ray evidence of bone atrophy and sclerosis. Taylor, in 1943, noted that several months elapsed between the hyperbaric exposure and the joint symptoms and that shaft lesions are usually asymptomatic. Osteonecrosis has been observed following caisson work at a pressure of 117 kPa (less than 12 metres of sea water equivalent), and also for as short a time as 7 hours, divided into two shifts, at 242 kPa. This disease has gone by many names, but when there is a clear relationship between pressure exposure and the subsequent development of aseptic necrosis, we now use the term ‘dysbaric osteonecrosis’ (DON) (Table 14.1).

Some synonyms for dysbaric osteonecrosis
Some synonyms for dysbaric osteonecrosis

DON has been known to develop within 3 months of the presumed causative diving exposure and has occasionally resulted from ‘once only’ exposures. Three of five men who escaped from the submarine Poseidon, in 1931 in the China sea after being at a depth of 38 metres for 2 to 3 hours, subsequently developed osteonecrosis.

The first report of DON in a diver appears to have been by Grutsmacher in the German literature in 1941. The disease affected the shoulder joint. Osteonecrosis affecting hips and shoulders has frequently been reported in commercial diving fishers. It is rare in recreational sport scuba divers.