Evaluation of the surgical approach and treatment outcomes in patients with chronic osteomyelitis of the tibia classified as anatomic type 3 and 4, physiologic class B (Cierny-Mader).

Analysis of surgical treatment of 68 patients (average age of 45.6 years) with chronic osteomyelitis of the tibia covered the period from June 1, 2013 till January 1, 2015. There were 49 males (72%). The first (I) group included 39 patients with type 3 chronic osteomyelitis of the tibia, the second (II) group – 29 patients with type 4 osteomyelitis. The follow-up was for 1–18 months. Duration of the surgery, intraoperative blood loss, causes of osteomyelitis and the frequency of infection recurrence were evaluated.

In the group I, 33.3% of patients underwent debridement of the infected site and replacement of the bone defect with an antibiotic-laden cement spacer. In 28.2% of cases, a biodegradable antibiotic delivery system was used for the replacement. 23.1% of cases involved muscle flap coverage of the bone and tissue defect, while 15.4% – treatment with external fixation. In the group II, the proportion of cases treated with external fixation was 58.6%. It was higher than in group I (p<0.01). 27.6% of patients in this group had their defects replaced with an antibiotic-laden cement spacer, whereas 10.3% had muscle flap coverage. One patient had amputation of the tibia.

Duration of the surgery and blood loss in group II was 2.4 and 1.7 times higher than in group I. The frequency of infection recurrence in both groups was comparable (about 13%). The average time of its manifestation was 20.8 days in group II and 41.6 days in group I. Infection recurrence after muscle flap coverage was not observed. S.aureus was the most common pathogen in both groups (50–60%). Microbial associations were isolated in 28.3 and 38% of cases in groups I and II, respectively. 33.3% of patients experienced infection caused by P.аeruginosa.

Differences in the blood loss and duration of the surgery were due to the larger volume of the affected tissues in type 4 chronic osteomyelitis of the tibia. High frequency of infection recurrence was observed in patients with microbial associations and P.aeruginosa. The surgical treatment of choice for these patients might be muscle flap coverage. It is necessary to consider the type of a pathogen for systemic and local antimicrobial therapy.