Risk of plate exposure in vascularized fibula flap for mandibular reconstruction in primary oral cancers

Authors: Pai AA, Chen AC-Y, Loh CYY, Hung S-Y, Tsao C-K, Kao H-K

Affiliation: Chang Gung Memorial Hospital, Taoyuan, Taiwan

Journal: Journal of Reconstructive Microsurgery, online March 7, 2025

PMID: 39961360

Key takeaways

• Plate exposure occurred in 28.8% (74/292) after fibula free flap (FFF) mandibular reconstruction for primary oral cancer.

  • Most exposures required surgery; ~50% underwent plate removal alone.

  • 13.5% were treated with plate removal and regional flap

  • 10.9% were treated with plate removal and free flap (6.8% ALT, 4.1% second fibula)

• Postoperative radiotherapy independently increased exposure risk (adjusted OR ≈3.7; p≈0.01)

  • Three-year plate exposure–free probability: 65.9% with radiotherapy vs 92.5% without; 55.3% with infection vs 91.2

• Postoperative wound infection was the strongest predictor (adjusted OR ≈10.7; p<0.001).

  • Three-year plate exposure–free probability: 55.3% with infection vs 91.2% without.

• Neither incision placement nor the need for external skin replacement was reported

Background

Hardware complications, particularly plate exposure, remain common after oromandibular reconstruction despite advances in computer-aided design/manufacturing (CAD-CAM) and virtual planning.

Objective

Identify perioperative risk factors for plate exposure after FFF mandibular reconstruction for primary oral cancers.

Methods

• Design/setting/level of evidence: Single-center retrospective cohort (2015–2019); Level III.

• Population: 292 consecutive primary oral cancer patients undergoing segmental mandibulectomy and immediate fibula osteocutaneous reconstruction.

• Exclusions: Non–head and neck cases, repeats/previous failures, missing radiotherapy records, inadequate follow-up or imaging.

• Follow-up: Standardized clinic schedule; study follow-up reported as 2 years.

• Variables: Demographics, TNM, defect type/length (Jewer classification for bone defect), plate type, number of osteotomies, ischemia time, re-exploration, postoperative radiotherapy (PORT), chemotherapy, postoperative wound infection, length of stay.

• Endpoints: Plate exposure; time to plate exposure (Kaplan–Meier).

• Statistics: Univariate and multivariable logistic regression (pre-specified covariates); Kaplan–Meier curves for exposure-free probability; α=0.05.

Results

• Overall exposure rate: 28.8% (74/292).

• Independent risk factors:

  • Postoperative radiotherapy: adjusted OR 3.73 (95% CI 1.35–10.30), p=0.011.

  • Postoperative wound infection: adjusted OR 10.71 (95% CI 5.15–22.26), p<0.001.

• Time-to-event: 3-year exposure–free probability 65.9% with PORT vs 92.5% without (p<0.001); 55.3% with infection vs 91.2% without (p<0.001).

• Other associations: Re-exploration associated on univariate analysis (OR 2.61; p=0.04) but not multivariable (p=0.27).

• Non-significant factors (multivariable): Plate type, defect type/length, number of osteotomies.

• Length of stay: Longer with exposure (26.1±12.5 vs 24.2±7.1 days; p<0.001).

• Management of exposure (n=74):

  • Conservative care: 24.3%.

  • Surgical: plate removal only 50%; plate removal + regional flap 13.5%; plate removal + free flap (ALT 6.8%, fibula 4.1%).

Conclusion

After fibula free flap mandibular reconstruction for primary oral cancer, postoperative radiotherapy and postoperative wound infection are independent, major drivers of plate exposure.

Strengths & limitations

• Strengths: Large, disease-specific cohort; multivariable modeling; inclusion of time-to-event analysis.

• Limitations: Retrospective design; potential confounding by indication for PORT; soft-tissue coverage or need for external skin replacement was not reported.

Critiques and questions

• Soft-tissue coverage matters: The study acknowledges difficulty quantifying soft-tissue coverage; yet healthy, durable soft tissue coverage is central to hardware preservation. Improved reporting measures (e.g., flap skin paddle area/neck tissue thickness) would strengthen inference.

• Infection pathway: Infection remained the dominant predictor (OR ≈10.7). It likely mediates exposure via wound breakdown and biofilm. Clinicians should focus on infection reduction to limit hardware exposure.

Bottom line: In FFF mandibular reconstruction for primary oral cancer, surgeons must take strong measures to ensure adequate soft tissue coverage, minimize infections and treat infections early/aggressively, and (presumably) place incisions lower on the neck when able.