Classification of pedicle ossification after maxillofacial reconstruction with bony free flap: An observational study.

INTRODUCTION: Maxillofacial reconstruction with bony free flap is a classical technique. However, pedicle ossification after such reconstruction is a misunderstood complication that is rarely reported in the literature. It is usually manifested as trismus, neck pain, and hard swelling, but it is predominantly asymptomatic and, thus, mainly incidentally discovered at a later stage. The aim of our study is to propose a classification for pedicle ossification based on both radiological features and vascular calcification progression. We also describe a case of metachronous ossification after two fibula free flap procedures. MATERIAL & METHODS: Our observational study includes all patients from our unit who underwent maxillofacial reconstruction with bony free flap from 2003 to 2018. We collected all cases of pedicle ossifications identified during the follow-up and described the radiological status of each one to categorise them in different groups and propose a classification scheme for the same. RESULTS: Radiological and histological analysis showed a progressive three-step evolution of pedicle ossification, starting from the media, progressing into the lumen, and then reaching completion in the extravascular region. The final stage was observed in all symptomatic patients. CONCLUSION: Pedicle ossification is a progressive process that passes through three successive histological stages that may be associated with factors such as smooth muscle cell phenotype modification [1]. This complication may lead to more severe clinical symptoms and may require surgery for removal of the calcification.

Consequences of bony free flap's pedicle calcification after jaw reconstruction.

INTRODUCTION: Most of the time, discovery of free flap pedicle calcification is fortuitous. We describe this phenomenon, try to elucidate its consequences, and discuss about prevention. We studied the effect of radiotherapy on the onset of calcification. We describe the first case of pedicle calcification with a scapula free flap. MATERIALS AND METHODS: We performed a retrospective study among the 162 bony free flaps harvested from 2003 to 2011. Follow-up included clinical examination, radiography, and head and neck computed tomography. We collected data including patients' age during free flap surgery, genre, primary disease, disease location, connected artery, ossification delay, clinical signs, flap vitality, and, eventually, calcification removal. We tested the effect of radiotherapy on the onset of calcification using a log-rank test. RESULTS: We retrieved data of 15 patients with pedicle ossification after bony free flap (9.2%). Fibula free flap was present in 14 patients and scapula free flap was present in 1 patient. We noticed vascular pedicle ossification in 42% of our maxillary reconstructions and in 7% of our mandibular reconstructions. The maxillary-to-mandibular ratio is 5:10. Pedicle ossification was discovered between 92 and 366 days after surgery. We performed radiography for diagnosis. Clinical signs were reported in 6 patients. We removed ossified pedicle in 3 patients (20%) owing to pain, trismus, or hard cheek swelling. No free flap failure was noted among the 15 calcified pedicles. There was no statistically significant difference in the effect of radiotherapy on the onset of calcification (P = 0.126). DISCUSSION: Ossification of the vascular pedicle is uncommon and probably underdiagnosed. Complications are rare, and surgical ossification removal should be reserved for patients with symptoms.