Vascularized Osteocutaneous Flaps in Oral-Maxillofacial Surgery Iliac Flap-DCIA 季彤 JI Tong DDS, MD Dept. of Oral & Maxillofacial – Head & Neck Oncology Shanghai Ninth People’s Hospital, Shanghai (200011) China It is a great pleasure for me to have all of you to this courses and hands-on workshop to develop your skills in microsurgical technique and learning more about head neck reconstruction. I’m also to thank our local organizer, Faculty of Dentistry，Prince of Songkla University; and Professor Samman to provide this beautiful place to held the course.

Iliac Crest As we know, In literatures, majority surgeon still prefer to use fibula especially in mandibular reconstruction as a first choice. In our team, using the iliac crest is more preferable for the defect less than 9 cm.

Revascularized Bone Flaps DCIA Scapula Fibula Bone Stock +++ + Bone Length ++ Vascular Pedicle Length Muscle Paddle Skin Island Flap 3 D Orientation Dental Implants

History 1972, Manchester’s - the anatomic similarities between the anterior ilium and the mandible 1979, Taylor et al - DCIA perfuse to the ilium through endosteal & periosteal mechanisms 1979, Sanders & Mayou - DCIA perforate thru the Abdominal muscle to the skin Ok! First of all I would like to review some history of the iliac crest. In 1972, Manchester’s described the anatomic similiarties between the anterior ilium and the mandible. In 1979, Taylor et al demonstrated DCIA perfuse to the ilium through endosteal & periosteal mechanisms. Also the same year, Sanders & Mayou described DCIA perforate to the multiple muscular layer of Abdominal to the skin.

1989, Urken et al clearly outlined versatility of DCIA flap 1986, Ramasastry et al - ascending branch of DCIA  internal oblique muscle 1989, Urken et al clearly outlined versatility of DCIA flap 1996, Brown described use DCIA flap for maxillary reconstruction Again, in 1986, Ramasastry et al demonstrated ascending branch of DCIA was responsible to the internal oblique muscle. In 1989, Urken et al clearly outlined the indications, utility, advantages and disadvantages of DCIA flap in oromandibular reconstruction and in the 1996, Brown described use DCIA flap for maxillary reconstruction.

Indications Partial Mandibular Reconstruction Palatomaxillary Reconstruction The iliac crest has proved to be useful and reliable for partial mandibular reconstruction with defect less than 9 cm And The iliac crest has also proven for palatomaxillary reconstruction

Vascular Anatomy Bone: Deep Circumflex Iliac vessel, br of either external iliac or femoral vessel Diameter: 1.5-2.0 mm for Artery Diameter: 2.5-3.0 mm for Vein Skin: Perforator thru the periosteum of iliac crest from DCIA Muscle – Internal Oblique Muscle: Ascending branch of DCIA The blood supply to the bone is DCIA and DCIV, and the supply to the skin is perforator thru periosteum of the iliac crest from DCIA. Also can take the muscle. The muscle base on the ascending branch of DCIA.

DCIA & Internal Oblique

Artery Deep circumflex iliac artery Vein Deep circumflex iliac vein

Endoseous Dental Implants Applicability Limited Bone Stock for Implant Insertion Next to the Iliac fossa From C.P. Cornelius

Flap Variants

Variation Anatomic of the Ascending Branch Now we look another diagram, variation anatomic of the ascending branch by Dr. Urken. In 65% of cases, the ascending branch originates from the DCIA within 1 cm medial to the ASIS. In 15% of cases, the ascending branch originated in a more medial location, 2 to 4 cm from the ASIS. In 20% of cases, there was no single dominant ascending branch. Urken M.L. Atlas of Regional and Free Flaps for Head and Neck Reconstruction.

Topographical Anatomy Before we harvesting the iliac crest, it is very important to look it at the topographical anatomy. This is ASIS; external iliac artery or femoral artery; the DCIA and the ascending branch.

Flap Raising We designed the incision line and marked the important landmarks, raising the skin and identified the aponeurosis; external oblique muscle. After we Divide the aponeurosis, and we can identified the internal oblique muscle.

Make an incision of internal oblique muscle at least 2. 0-2 Make an incision of internal oblique muscle at least 2.0-2.5cm away from the iliac crest. Careful dissection allows identification of the ascending branch of the DCIA and the followed to its junction with the DCIA/DCIV and also identified the lateral femoral nerve. Divide the transversalis muscle and the iliacus muscle. The bone cuts are made with an oscillating saw.

Closure of the Donor Defect Reconstruct the abdominal wall by fixed the divided muscle with sutures to the pelvis or fascia Hernia Formation After harvesting the iliac bone, to reduces and avoid the risk of hernia formation. We must pay attention for closure of the donor defect, by fixed the divided muscle with sutures to the pelvis or muscle surround it.

Iliac Crest Free Flap Advantages Thick bone stock Easy positioning Defect closed primarily Minimal donor deformity Support osseointegrated implants 1.The iliac crest has been used extensively for oromandibular reconstruction. It is particularly well suited for this purpose due to the natural contour of the mandible, and 2.The utility of the internal oblique muscle in the formation of a thin immobile soft tissue closure over the bone intraorally. 3.The iliac crest is very important bone because its allowed for the placement very long implant, because you can get the big bone. This is 20mm implant, you can place any size of implant in iliac crest

Disadvantages -The short vascular pedicle -Bulky soft tissue component -Poor reliability of skin paddle -Risk for hernia formation -Postop ambulation-pelvic pain Because of the poor vascularity to the skin paddle, some surgeon avoid using this skin paddle and also the problem with the iliac crest is the morbidity and the difficulty when the patient want walks after surgery, because of the big defect in the abdominal wall.

Summary Pedicle Length ≥ 5-6 cm Pedicle Diameter: Artery / Vein, 2-3 mm Graft Size: Bone Length ≤ 16 cm (9 cm for Implant) Segmental Blood Supply Multiple Osteotomies Possible Dental Implant Possible Excellent Vascularity of Internal Oblique Muscle

Thanks