Outcomes of free flap reconstruction for mandibular ORN: Systematic review and meta-analysis

Objective: This study aims to evaluate the success rates and complications associated with different free flap donor sites used in surgical reconstruction for mandibular osteoradionecrosis, providing insights to aid clinical decision-making.

Data sources: MEDLINE, Embase, Cochrane, and Web of Science.

Review methods: Comprehensive database searches were conducted up to October 2023. Three independent reviewers screened articles per PRISMA guidelines. This review is registered with PROSPERO (CRD42023456929). Meta-analysis, using inverse variance statistical method and a random effects model, was performed with OpenMeta software (Version 10.12, Brown University, USA). Study quality was assessed via the methodological index for non-randomized studies (MINORS).

Results: Nineteen full-text articles met inclusion criteria, encompassing 397 patients and 424 free flap procedures. Patients averaged 54.8 years old; 27.5 % were female. Squamous cell carcinoma was the main radiation indication (83.1 %). Flap types included fibula (63 %), iliac crest (36 %), scapula (3.7 %), and radial forearm (3.5 %). Symptoms of osteoradionecrosis appeared on average four years post-radiation therapy, with a mean dose of 6346 cGy. Pooled postoperative complication rate was 22.5 % (95 % CI 0.165-0.284, I²:48%). Radial forearm flaps had the lowest complication rate (13.5 %, 95 % CI 0.026-0.295, I²:0%), while scapula flaps had the highest (34.9 %, 95 % CI 0.039-0.66, I²:40.3 %). Fibula flaps had the lowest failure rate (3.3 %, 95 % CI 0.003-0.025, I²:0%), while iliac crest flaps had the highest (11.9 %, 95 % CI 0.022-0.260, I²:60.4 %).

Conclusion: The fibula is the preferred flap for mandibular reconstruction due to its low failure rate. Radial forearm flaps show the fewest complications. More robust, multi-institutional prospective studies are needed.