Ultrasound and colour Doppler sonography in acute osteomyelitis in children.

Early diagnosis of osteomyelitis is of paramount importance to avoid irreversible sequelae. This often requires a multimodal approach. The purpose of the present study was primarily to evaluate how ultrasound might be useful in early diagnosis of osteomyelitis in the paediatric age group. The evolution of ultrasound findings with progression and resolution of disease was also analysed. In this prospective study, 55 children with osteomyelitis of limbs were subjected to sonographic examination including colour Doppler study. The sonographic machine used was a LOGIC-500, using a linear multifrequency transducer (7-9 MHz). Ultrasound guided aspiration was performed in all cases showing sub-periosteal accumulation of fluid, and the aspirate was sent for culture and sensitivity report. Surgical drainage was undertaken in all patients in which a sub-periosteal abscess was demonstrated. Anechoic fluid accumulation contiguous with bone was highly suggestive of osteomyelitis, whereas presence of soft tissue between the bone and the fluid suggested a non-osseous origin of the fluid. Sub-periosteal accumulation of fluid was seen in 42 cases (76.3%). A subperiosteal abscess with periosteal reaction was demonstrated in 35 children (63.63%). Colour Doppler study revealed increased vascular flow within or around the affected periosteum in all cases. Concurrent involvement of a joint was noted in 13 cases. Ultrasound is a rapid, cheap, easily available, non-ionising and reasonably accurate diagnostic modality. It also helps in localising the lesion for diagnostic aspiration. Serial ultrasound and technical innovations such as colour Doppler sonography further help in monitoring the progression and resolution of the disease.