Treatment of pathologic fracture following postoperative radiation therapy: clinical study

Consensus of free flap complications: Using a nomenclature paradigm in microvascular head and neck reconstruction

BACKGROUND

We aim to define a set of terms for common free flap complications with evidence-based descriptions.

METHODS

Clinical consensus surveys were conducted among a panel of head and neck/reconstructive surgeons (N = 11). A content validity index for relevancy and clarity for each item was computed and adjusted for chance agreement (modified kappa, K). Items with K < 0.74 for relevancy (i.e., ratings of "good" or "fair") were eliminated.

RESULTS

Five out of nineteen terms scored K < 0.74. Eliminated terms included "vascular compromise"; "cellulitis"; "surgical site abscess"; "malocclusion"; and "non- or mal-union." Terms that achieved consensus were "total/partial free flap failure"; "free flap takeback"; "arterial thrombosis"; "venous thrombosis"; "revision of microvascular anastomosis"; "fistula"; "wound dehiscence"; "hematoma"; "seroma"; "partial skin graft failure"; "total skin graft failure"; "exposed hardware or bone"; and "hardware failure."

CONCLUSION

Standardized reporting would encourage multi-institutional research collaboration, larger scale quality improvement initiatives, the ability to set risk-adjusted benchmarks, and enhance education and communication.

Restricted Mouth Opening in Head and Neck Cancer: Etiology, Prevention, and Treatment

Restricted mouth opening or trismus is often encountered in patients with head and neck cancer. The restriction may be the presenting sign of malignancy, a sequela of tumor site or growth, an adverse effect of oncologic treatment, or a first sign of tumoral recurrence. In general, any insult to the temporomandibular joint, masticatory muscles, or their neural innervation may cause limitation in mouth opening. The etiologies leading to trismus are as follows: myospasm secondary to tumor infiltration; reflectory myospasm; radiation-induced myositis and myofibrosis; temporomandibular joint involvement with tumor; unfavorable postsurgical scarring; muscle and joint atrophy secondary to immobilization; pain; jaw fracture and hardware failure; and infection. Preventive measures should be implemented before, during, and after treatment. These measures include identification of high-risk patients, utilization of dose-sculpting radiation techniques whenever possible, performing reconstruction at the same time of resective surgery whenever feasible, and initiating mobilization exercises as early as possible. When trismus develops, treatments are often challenging and disappointing. These include physical therapy, mouth opening appliances, drug therapy, and release surgery. All medical specialties dealing with head and neck cancer should be familiar with the diagnosis and prevention of trismus and make an effort to ensure patients are referred to the appropriate care when needed. Trismus should not be considered a trivial sequela of head and neck cancer.

Osteoradionecrosis of the Midface and Mandible: Pathogenesis and Management

Radiation therapy is an important and commonly used treatment modality for head and neck cancers. Osteoradionecrosis (ORN) is a potential debilitating complication of treatment, which most commonly affects the mandible. Management strategies are tailored to the severity of disease. Medical management including oral rinses, irrigations, antibiotics, and pharmacological treatments is viable for mild-to-moderate ORN. More severe disease is best addressed with a combination of medical management and surgical intervention aimed at aggressively removing devitalized tissue until bleeding bone is encountered and reconstructing the soft tissue and bone defect. Reconstruction with either regional vascularized flaps or vascularized osteocutaneous free flaps in case of larger full-thickness bone defects (greater than 6 cm) or anterior mandible (medial to mental foramen) is most appropriate. Maxillary ORN complications can present with a wide range of functional problems and facial disfigurement. Life-threatening and time-sensitive problems should be treated first, such as skull base bone coverage or correction of severe ectropion, to avoid blindness from exposure keratopathy. Then, less time-sensitive issues can be addressed next, such as nasal obstruction, velopharyngeal insufficiency, and chronic tearing. It may require a combination of specialists from different disciplines to address various issues that can arise from maxillary ORN.

Corticotomy for orthodontic tooth movement

Corticotomy was introduced as a surgical procedure to shorten orthodontic treatment time. Corticotomy removes the cortical bone that strongly resists orthodontic force in the jaw and keeps the marrow bone to maintain blood circulation and continuity of bone tissues to reduce risk of necrosis and facilitate tooth movement. In the 21st century, the concept of regional acceleratory phenomenon was introduced and the development of the skeletal anchorage system using screw and plate enabled application of orthopedic force beyond conventional orthodontic force, so corticotomy has been applied to more cases. Also, various modified methods of minimally invasive techniques have been introduced to reduce the patient's discomfort due to surgical intervention and complications after surgery. We will review the history of corticotomy, its mechanism of action, and various modified procedures and indications.

Development of an experimental model for radiation-induced inhibition of cranial bone regeneration

Background

Radiation therapy is widely employed in the treatment of head and neck cancer. Adverse effects of therapeutic irradiation include delayed bone healing after dental extraction or impaired bone regeneration at the irradiated bony defect. Development of a reliable experimental model may be beneficial to study tissue regeneration in the irradiated field. The current study aimed to develop a relevant animal model of post-radiation cranial bone defect.

Methods

A lead shielding block was designed for selective external irradiation of the mouse calvaria. Critical-size calvarial defect was created 2 weeks after the irradiation. The defect was filled with a collagen scaffold, with or without incorporation of bone morphogenetic protein 2 (BMP-2) (1 μg/ml). The non-irradiated mice treated with or without BMP-2-included scaffold served as control. Four weeks after the surgery, the specimens were harvested and the degree of bone formation was evaluated by histological and radiographical examinations.

Results

BMP-2-treated scaffold yielded significant bone regeneration in the mice calvarial defects. However, a single fraction of external irradiation was observed to eliminate the bone regeneration capacity of the BMP-2-incorporated scaffold without influencing the survival of the animals.

Conclusion

The current study established an efficient model for post-radiation cranial bone regeneration and can be applied for evaluating the robust bone formation system using various chemokines or agents in unfavorable, demanding radiation-related bone defect models.

Primary sinonasal mucosal melanoma simulated as cystic lesions: a case report

Sinonasal mucosal melanoma (SNMM) in the maxillary sinus is a rare disease condition. Compared to oral mucosal melanoma, SNMM has a bulky, exophytic, and polypoid appearance, is weakly pigmented, and associated with unspecific symptoms. Due to these features, SNMM in the maxillary sinus has been misdiagnosed as nasal polyps and chronic sinusitis. In this case report, we described SNMM occurring in the right maxillary sinus simulated as a cystic or benign lesion. Cortical bone thinning and expansion were observed around the mass. The excised soft mass was encapsulated and weakly pigmented. The mass was clearly excised and covered with a pedicled buccal fat pad graft. Diagnosis using immunohistochemistry with S-100 and homatropine methylbromide-45 (HMB-45) is critical for proper treatment.

Reconstruction of partial maxillectomy defect with a buccal fat pad flap and application of 4-hexylresorcinol: a case report

Mucoepidermoid carcinoma (MEC) is the most common type of malignant neoplasm in the minor salivary gland. The hard palate is a frequently involved site of MEC. The treatment of low-grade MEC on the hard palate is wide local resection with a tumor-free margin. In the present case, the maxillary defect was reconstructed using a buccal fat pad (BFP) flap, followed by application of 4-hexylresorcinol (4HR) ointment for 2 weeks. The grafted BFP successfully covered the tumor resection defect without tension and demonstrated complete re-epithelialization without any complications.