Session VII - Tibia

The Incidence, Results of Treatment, and Causes of Tibial Osteomyelitis after Reamed Intramedullary Nailing

Stuart D. Anderson, MD; Charles M. Court-Brown, MD, FRCS; Royal Infirmary of Edinburgh, Edinburgh, United Kingdom

Purpose: We examined the incidence of osteomyelitis after reamed intramedullary tibial nailing and investigated the reasons for infection. The effect of osteomyelitis on union time and the necessity for exchange nailing and reconstructive surgery were also examined.

Methods: A detailed analysis was undertaken of 1106 tibial fractures treated by reamed nailing over a 15-year period in one trauma unit. The majority of the patients had been prospectively documented, and a retrospective chart and radiographic review was used to complete the database. All fractures were classified according to the Gustilo and Tscherne classifications, and the incidence of infection, union time, and compartment syndrome was noted. The type and success of plastic surgery undertaken and the requirement for exchange nailing or bone reconstruction to facilitate union were also determined.

Results: Analysis showed that 16 (1.9%) of the 859 closed fractures became infected. There were 19 (7.7%) infections in the 247 open fractures with an incidence of 6.9% in the Gustilo Type I fractures, 6.6% in the Gustilo Type II fractures, and 16.4% in the Gustilo IIIB fracture group. There were no infections in the Gustilo IIIA group. The effect of osteomyelitis was significant, with prolonged union times noted in both closed and open fractures. The mean union time for uninfected closed fractures was 17.8 weeks, with 57.3 weeks for infected closed fractures. The mean union time for the uninfected IIIB fractures was 42 weeks compared with 73.7 weeks for the infected IIIB fractures. Analysis of the requirement for exchange nailing and bone reconstruction techniques showed that these were required in 4.4% of uninfected closed fractures and 43.7% of infected closed fractures. The equivalent figures in the open fracture group were 21.6% and 77.7%, respectively. Examination of the probable cause of infection in the closed fractures showed that two (10%) patients had evidence of thermal necrosis and three (15%) had required fasciotomy for compartment syndrome. In the open fracture group, eight patients (42.2%) had evidence of partial flap failure and three (15.8%) had required fasciotomy. There was a 15.8% infection rate in open fractures complicated by compartment syndrome compared with 2.5% in closed fractures.

Discussion: The overall infection rates for closed and open fractures were similar to those reported in previous studies. The findings indicated that reamed nailing of closed and open tibial fractures is not associated with a high incidence of osteomyelitis compared with other fixation methods. The prolonged union times and the requirement for secondary surgery to treat osteomyelitis indicated the need for early diagnosis and treatment. However, the study raised two important and hitherto unrecognized issues related to the consequences of partial flap failure and the incidence of infection after compartment syndrome. Failure of a corner or edge of a flap to unite is usually treated by both orthopaedic and plastic surgeons by allowing the defect to granulate. Our results suggest that this is inappropriate and that partial flap failure is a cause of infection that should be treated by the use of a second flap. Infection after compartment syndrome can occur for two reasons. In this study the three infections that followed closed fractures with compartment syndrome all occurred because of serial delayed fasciotomy closures. There has been increased interest in secondary direct fasciotomy wound closure in recent years, and we believe that the technique will lead to an increased incidence of osteomyelitis. The three infections that followed compartment syndrome in open fractures were associated with severe rapid myonecrosis that occurred despite early fasciotomy. The results of the management of open tibial fractures complicated by compartment syndrome are similar to those of IIIB fractures, emphasizing the considerable soft tissue damage and poor prognosis of these fractures.

Conclusions: Reamed intramedullary nailing of both closed and open tibial diaphyseal fractures is associated with an acceptable osteomyelitis rate when compared with other methods. The results indicate the importance of detecting and treating partial flap failure and compartment syndrome to minimize the risk of infection.