Reconstruction of this defect should focus on restoration of the maxillary alveolus with the bony portion of the flap, and sealing the palate with the soft tissue portion of the flap. This flap can be adapted to restore any length of the horizontal component of the defect.
It is critical that the surgeon pays strict attention to the vascular pedicle geometry as it passes through the tunnel into the neck.
The fibula flap is a practical option for restoring these defects, however other bone containing free flaps alternatives include: Iliac crest, scapula, and radial forearm osteocutaneous to list a few.
2. Preparation of the recipient site
The bone margins are trimmed to allow for adaptation of the flap.
The fibula osteocutaneous flap is harvested in the standard fashion with the following considerations:
The maximal length of fibula should be harvested so as to obtain the longest vascular pedicle possible.
Skin portion of the flap should be positioned more distally on the bone to optimize its position for reconstruction of the soft tissue defect.
Maximizing the vascular pedicle
The length of pedicle necessary to reach the neck vessels should be measured. The periosteum of the proximal portion of the fibula should be elevated off the bone to maximize pedicle length.
The fibula is osteotomized with a reciprocating saw and the excess proximal bone is discarded.
Contouring of the bone graft
Wedge shape ostectomies are made in the fibula to create the proper 3-dimentional geometry of the bony defect. A template can be used to aid in the contouring of the bone.
The osteotomized fibula segments should have a minimum length of 2 cm to maintain bone viability. The fibular segments are joined by miniplates. The edges of the bones can be further contoured with a burr to maximize bone contact.
The vascular pedicle should be on the palatal side, while the plates should be fixed on the buccal side of the construct.
Insetting of the flap
The vascular pedicle is tunneled through the cheek to reach the recipient neck vessels. The use of a silicone tube could be helpful to protect and avoid pedicle rotation during tunneling.
The fibula construct is secured with miniplates to the adjacent skeletal buttresses.
The soft tissue component of the flap is rotated into its preplanned position to restore the soft tissue defect with care not to create undue torsion or tension to the vascular pedicle.
It is sutured to the sublabial mucosa (laterally) and cut edge of the palate (medially) with resorbable suture to create a water tight seal.
4. Vascularization of flap
The detailed procedure for the revascularization is outside the scope of this surgery reference. However, in short the procedure consists of the following steps:
A neck incision is made and the appropriate recipient vessels are selected in the neck and dissected so as to be available for anastomosis
Creation of a tunnel from the ptyerigoid region to the neck incision lateral to the mandible of adequate size for the passing of the vascular pedicle
A coronoidectomy may be helpful to widen the tunnel adequately
The recipient and the donor vessels adventitia are cleaned under a microscope
Appropriate vessel geometry is assured and the vessels are placed into a microvascular clamp and anastomosis carried out eg. using 9-0 nylon sutures
Vascularization is restored after both arterial and venous anastomoses are completed
For adequate vessel length to create the anastomoses (without tension), vein grafts are sometimes necessary.
5. Aftercare following corrections of secondary deformities of the alveolus and palate
Analgesia as necessary
Antibiotics (many surgeons use perioperative antibiotics). There is no clear advantage of any one antibiotic but evidence supports their use for 24h. The spectrum should be according to the existing bacterial flora, especially in the combined intra oral and paranasal sinuses.
Steroids may help with postoperative edema.
Regular perioral and oral wound care has to include disinfectant mouth rinse, lip care, etc.
Antibiotic ointment is used on skin incision (when indicated) for 72 hours.
Reconstruction with free flap
When a free flap is utilized, it should be regularly monitored to ensure vascular integrity. Physical examination, assessing the flap color, turgidity, and capillary refill should be routine for at least the first 48 hours postoperatively. Hand-held Doppler probes can be used to assess blood flow. In case of doubt of the vitality of the flap, pin-prick assessment with a 25 gauge needle to look for bright red bleeding. In cases of buried flaps, an implantable Doppler placed just distal to the venous anastomosis can be utilized. Radial forearm free flap The radial forearm free flap donor site should be closed with a skin graft and a bolster placed over the area. The arm is then cast or placed in a volar splint for 7 days prior to removal to ensure graft take. If bone is taken and the radius plated, appropriate follow-up with an orthopedic or hand specialist should be arranged.
Fibula free flap After a fibula free flap, the donor lower leg should be cast with the ankle slightly dorsiflexed for 5 days. The patient can touch-down their body weight as tolerated. After the cast is removed they can ambulate and work with physical therapy to optimize leg function. A splint should be placed to keep the foot flexed when in bed.
Scapula free flap Flaps from the subscapular system require no particular rehabilitation care but closed suction drains should remain until a minimal output is still draining to avoid seroma formation.
Rectus abdominis and iliac crest Rectus abdominis and iliac crest donor sites require that the patient not strain or lift heavy objects for at least 4 weeks to avoid hernia formation.
Anterolateral thigh Patients should avoid climbing stairs for 2-4 weeks after surgery. They should also be observed for seroma formation at the wound bed.
Remove sutures from skin after approximately 7 days if non resorbable sutures have been used. Moisturizing lotion should be used on the skin wounds to minimize excessive scarring after sutures are removed. Avoid sun exposure and tanning to skin incisions for several months.
Diet depends on the correction method.
For patients with free flap reconstruction of the maxilla, a feeding tube is placed during sugery allowing the patient to be kept nil per os for 5-7 days. If issues develop with velopharyngeal insufficiency or dysphagia, assessment by a speech and swallowing rehabilitation specialist may be indicated. When the lateral nasal wall is reconstructed, especially when a bulky soft tissue flap is used, the nasal airway should be stented with gauze packing or a merocel sponge for five days.
Patients with intraoral incisions and/or wounds must be instructed in appropriate oral hygiene procedures. A soft toothbrush (dipped in warm water to make it softer) should be used to clean the surfaces of the teeth. Chlorhexidine oral rinses should be prescribed and used at least 3 times a day to help sanitize the mouth. For larger debris, a 1:1 mixture of hydrogen peroxide/chlorhexidine can be used. The bubbling action of the hydrogen peroxide helps remove debris.
Typically the patients are seen in clinical follow-up one week after discharge, and then on a weekly basis until such time the clinician determines that less frequent follow ups are needed.