Assessment of bone viability in patients with osteomyelitis: Preliminary clinical experience with laser doppler flowmetry

The intraoperative determination of bone viability is of fundamental importance in the surgical management of osteomyelitis. Recurrent infection will result from inadequate debridement, whereas reconstructive problems will be magnified by overzealous resections. The purpose of this article is to report the use of laser Doppler flowmetry (LDF) as a surgical adjunct allowing quantitative determination of bone viability in patients with osteomyelitis. Twenty-five patients with osteomyelitis underwent surgical debridement using LDF to assist with the intraoperative identification of necrotic bone and have been observed for at least 6 months. The LDF probe is placed directly on the bone and the output signal is channeled into an oscilloscope that calculates and displays the mean value of the signal in millivolts (mV). All patients underwent radical surgical debridement, including hardware removal if present and resection of nonviable bone. Bone debridement was continued when possible until LDF measurements in excess of 100 mV were obtained. Information regarding bone vascularity obtained with the LDF had a direct influence on the extent of bone debridement in all cases. The patients have been observed for an average of 16 months. No complications were associated with the use of LDF. All readings were pulsatile. Five patients had recurrence of infection. The average LDF reading following debridement for patients with recurrent infection was 72 mV, compared to 107 mV for patients without recurrence (p ≤ 0.025). All fractures were healed, although some required supplemental surgical management, including bone grafting or external fixation. We recommend the laser Doppler as a surgical appliance useful in the management of acute and chronic osteomyelitis. A LDF reading of 75 mV or less is indicative of nonviable bone and may predict recurrent infection. Laser Doppler flowmetry provides a quantitative and reliable means to assess bone viability.