Soft Tissue Coverage and Outcome of Gustilo Grade IIIB Mid-Shaft Tibial Fractures: A 15-Year Experience

Gustilo grade IIIB mid-shaft tibial fractures in 64 patients were treated at the Mayo Clinic between 1990 and 2004. The male to female patient ratio was 2.4:1, with an average age of 37.5 years. Flap coverage performed was either acute (<1 week), intermediate (1–4 weeks), or delayed (>1 week) in 48%, 29%, and 23% of the patients, respectively. Soft tissue coverage was accomplished with either a soleus flap or a free tissue transfer. There were 25 (38%) soleus flaps and 40 (62%) free flaps performed in total.

Of the soleus flaps, 17 (68%) were performed acutely, 3 (12%) intermediately, and 5 (20%) delayed. Six (24%) flap failures occurred, requiring a salvage free flap in 5 (83%) and a below-knee amputation in 1 (17%). The average age of the group was 35 years (17 to 66 years), with a male to female ratio of 3:1. Primary healing rates for the respective subgroups were 8 of 17 (47%), 0 of 3 (0%), and 0 of 5 (0%), respectively. All non-unions required bone grafts for ultimate fracture healing.

There were 40 (62%) free flaps performed. Fourteen (35%) were performed acutely, 16 (40%) intermediately, and 10 (25%) delayed. There were 4 (10%) failures, of which 2 (50%) were salvaged with another flap and 2 (50%) needed a below-knee amputation. The average age of the group was 40 years (12 to 86 years), with a male to female ratio of 2:1. Primary healing rates for the respective subgroups were 6 of 14 (43%), 6 of 16 (38%), and 0 of 10 (0%), respectively, both bone grafts required in all for ultimate fracture healing. The overall flap failure rate was 15%.

The data showed that despite immediate soft tissue coverage, over 40% of mid-tibial Gustilo grade IIIB fractures went on to non-union. In addition, regardless of the type of flap used (soleus vs. free tissue), the rate of non-union remained similar. Furthermore, all fractures covered by soleus flaps after 1 week ended in non-union, and a similar trend was seen with free flaps. The overall soleus flap failure rate was 24% and the free flap failure rate was 10%. However, a 70% salvage rate was observed with a second flap.