Iliac crest free flap: a reappraisal of indications and donor site complications

The iliac crest flap, due to its bone quality and 3D volumetric characteristics, is considered a good alternative for the reconstruction of large bone defects, specifically maxillectomy and mandibulectomy defects. However, recently, it has lost some popularity as a bone flap, in part due to donor site morbidity risk. The purpose of this study is to retrospectively evaluate the iliac crest free flap donor site morbidity at our centre. A series of patients submitted to deep circumflex iliac artery free flap transfer between January 2000 and January 2020 was evaluated. Patient clinical information was retrospectively collected from electronic medical records and by direct interview and physical examination, including the following: demographic characteristics; flap style (inclusion or not of the antero-superior iliac spine (ASIS)); donor-site post-operative complications (hematoma, infection); donor site sequelae: chronic pain, lateral thigh hypoesthesia/analgesia; hernia/abdominal bulge; and patient overall opinion of the aesthetics and morbidity of the donor site. In the patients with preserved ASIS, the presence of fracture of the ASIS was also evaluated. Data was analysed using SPSS version 26.0. Categorical variables were presented as percentages and numeric variables as means. Results are expressed as percentages or means with standard deviation (SD) for continuous variables. The χ2 test was used to compare non-continuous variables. Results where p < 0.05 were considered to be statistically significant. From a total of 84 patients submitted to iliac crest flap-based reconstruction from January 2000 to January 2020, a total of 32 agreed to participate in this study, with a mean postoperative follow-up of 8.2 years. Donor-site hematoma and surgical site infection occurred in one patient each. Chronic pain was present in eight (25%) of the patients, abdominal bulge was present in eight (25%), and abdominal hernia in four (12.5%). Permanent hypoesthesia in the territory of the LFCN (lateral femoral cutaneous nerve) was present in twelve (31.3%) of the patients. Gait dysfunction was permanent in two (6.3%) patients and overall patient donor site evaluation was “no concern” in 30 (93.7%) patients and “moderately concerned” in two patients (6.3%). In the group with ASIS preserved, one patient had a fracture of the ASIS. From the statistical analysis, in this sample, the only parameter that was influenced by the preservation of the ASIS was the abdominal bulge (p = 0.010). The iliac crest free flap is a versatile flap for the reconstruction of large and complex bone defects, especially of the maxilla and mandible. Although it has a potential risk for donor site morbidity, it can be reduced by meticulous and careful dissection and donor site closure. The preservation of the ASIS may reduce the risk of abdominal bulge. Level of evidence: Level IV, therapeutic study.