LIMB SALVAGE AND RECONSTRUCTION OF THE SEPTIC DISTAL TIBIA AND ANKLE

Abstract

Distal tibia and ankle sepsis can threaten the viability of the limb. We present the management protocol and results in 37 patients with chronic infection of the distal tibia and ankle, followed up for a mean of 4 years.

The mean age was 45.6 years. Host type A were 21 patients, type B were 9, and type C were 7 patients. Treatment included radical debridement, multiple cultures sampling and local antibiotic application. Twenty seven patients required bone stabilisation, whereas 3 host C patients were amputated. Soft tissue coverage included 5 free muscle flaps, 3 soleus flaps and 5 pedicle fasciocutaneous local flaps. Bone defects of a mean of 6.3 cm (3–13cm) in 20 cases were treated with distraction histogenesis (13 cases) or the free fibula vascularised graft (7 cases).

Mean hospitalisation time was 26.2 days (host-A: 19.6 vs. host B/C: 32.2, p=0.036). Host-A patients required 2.3 operative procedures whereas host-B/C 3.9 (p=0.01). Union occurred in 26/27 (96%) of cases requiring fixation (one ankle arthrodesis revision/host-B patient). External fixation frames were kept in situ for a mean of 31.7 weeks (12–85). Mean leg length discrepancy was 0.6 cm. Ankle arthrodesis was performed in 7 patients (5% among host-A patients vs. 38% among B/C). Independent ambulation was achieved in (35/37) 95%. All patients were satisfied with the result. Bacteriology revealed Staph. aureus in 71%, whereas 38% were polymicrobial (7% in host-A vs. 88% in B/C patients, p< 0.001). Infection recurrence occurred in 5.4% (none in host-A vs. 13% in B/C patients, p=0.03), whereas the overall complication rate was 43% (24% in host-A vs. 75% in B/C patients, p=0.02).

Functional limb salvage without leg length discrepancy was possible in 92% of cases. Systemically compromised patients required longer hospitalisation, more operative procedures, had frequently polymicrobial infections and more complications.