Craniomaxillofacial Reconstructive and Corrective Bone Surgery - part 7 doc

c d a b FIGURE 42.2 Severe resorption of a nonvascularized iliac crest graft for reconstruction of the ascending ramus and condyle in a 50-year-old patient. Note the pencil-like shape of the severely atrophic bone graft with additional soft tissue shrinkage. F IGURE 42.3 (a,b) Twelve-year-old boy following reconstruction of the right condyle with a costochondral graft. Excessive growth over- shoot 3 years after reconstruction with lateral deviation of the mandible to the left. (c,d) X-ray of the patient immediately and 3 years postoperatively demonstrating the massive mandibular shift. 42. Microvascular Reconstruction of the Condyle and the Ascending Ramus 465 After positioning of the remaining condyle, plate fixation to the vascular graft should be performed at least with two or three screws at the condyle. Otherwise, removal of the condyle with replacement by the vascularized bone graft must be considered. Alternatively, the remaining condyle may be fixed to the proximal aspect of the vascularized graft according to Hidalgo. 19,20 If a small condyle shows severe signs of osteoporosis with un- secure bone hold, the condyle should also be removed and re- placed by the graft. In grafts with sufficient bone volume, an inlay-type osteotomy may facilitate fixation of the remaining short condyle with positioning screws (Figure 42.5). Several donor sites are useful for reconstruction of the ascending ramus and condyle. The iliac crest is suitable in cases necessitating reconstruction of larger aspects of the ascending ramus and condyle including potentially tooth-bearing areas of the posterior mandibular body. In these situations, the distal portions of the new mandible allow for insertion of dental implants (Figure 42.6). The grafts are mostly harvested from the ipsilateral hip, if ipsilateral donor site vessels are present. The pedicle then arises at the angle and an appropriate curvature of the graft is given. Defects of the ramus and condyle may be reconstructed with grafts from the contralateral hip, if the recipient vessels are on the contralateral side and the vascular pedicle is to be positioned at the chin area (Figures 42.7 and 42.8). The ascending ramus may also be reconstructed with grafts from the scapula region which may offer a lower complication rate at the donor site and less graft volume compared to iliac crest grafts. 15,20,21–24 The thin bone with a thicker lateral scapula border can easily be modeled to replace parts of a b c d FIGURE 42.4 (a) Three-dimensional soft tissue imaging before reconstruction of a defect of the right ascending ramus demonstrates lateral shift to the left side necessary for symmetrical chin projection. (b,c) Whereas the major mandibular segment has to be repositioned laterally to the left, the condyle has to be repositioned poste- riorly and laterally. (d) In cases with the condyle still in situ, the condyle first is mobilized and the muscle process resected. After- ward, the condyle can be kept in its original position with the mini- plate temporarily fixed to the maxilla. Then the length of the ascending ramus and the mandible can be estimated. Additional pros- thetic devices fixed to the maxilla with screws in the midline may help to get an orientation for sagittal extension of bone grafts in patients with large mandibular reconstructions. 466 R. Schmelzeisen and F.W. Neukam the ascending ramus and the condyle. The volume of the necessary soft tissue component can be tailored individually rang- ing from different amounts of adherent muscle cuffs to a larger portion of deepithelialized soft tissue or even two separate skin flaps for extraoral and intraoral lining (Figures 42.9 and 42.10). The inferior aspect of the scapula tip forms the new condyle with a vascular pedicle located near the mandibular angle (Figure 42.11). Today, fibula grafts are to be regarded as the grafts of choice for reconstruction even of smaller aspects of the ascending ramus and condyle. They can be harvested simulta- neously and without changing the patient’s position on the operating table. Due to the segmental vascularization, various osteotomies are possible to match the shape of the original mandible. With experience, the osteotomies can be performed so that the fibula matches the mandibular angle and especially the slight outward deviation of the ascending ramus and the condyle in a cranial direction. FIGURE 42.5 (a) If the condyle is still in situ, it may be fixed to a vascularized iliac crest graft with positioning screws after prepara- tion of an inlay-like osteotomy. (b,c) The residual condyle is too small to be fixed in situ to a fibula graft. Therefore, the condyle was removed and fixed to the cranial aspect of a vascularized fibula graft. Care must be taken not to fracture thin aspects of the brittle bone during screw osteosynthesis. a b c 42. Microvascular Reconstruction of the Condyle and the Ascending Ramus 467 F IGURE 42.6 (a) X-ray following reconstruction of the right body and ascending ramus with a vascularized iliac crest graft, dental implant insertion, and prosthodontic treatment with implant-fixed dentures. (b,c) Three-dimensional CT imaging of the posterior aspect of the newly formed body of the mandible shows sufficient bone volume for insertion of dental implants. This sufficient bone volume with bicortical bone structure and a large volume of medullary bone is also given in the ascending ramus. a b c 468 R. Schmelzeisen and F.W. Neukam FIGURE 42.7 (a) In situations with a bone defect at the side of the recipient vessels, the iliac crest graft is harvested from the ipsilateral hip. (b) If the vessels are located at the contralateral side, the contralateral hip may be used to locate the vascular pedicle anteriorly. a b a b c d e f FIGURE 42.8 (a,b) Sixteen-year-old female patient following hemimandibulectomy, full-dose chemotherapy, and radiotherapy for os- teogenic sarcoma of the left mandible. (c) For reconstruction, a vascularized iliac crest graft was harvested from the ipsilateral hip. At that time, dental implants were inserted primarily. (d) Postoperative x-ray. (e) Situation 1 year following reconstruction showing an adequate transverse relationship of the mandibular profile. (f) Intra- oral situation after prosthodontic reconstruction with implant-borne dentures. 470 R. Schmelzeisen and F.W. Neukam a b c d e f FIGURE 42.9 (a) Clinical view of a patient following resection of a bone tumor necessitating temporary reconstruction of the condyle and ascending ramus with a plate and condylar prosthesis. Slight soft tissue deficit in projection of the left preauricular region. (b,c) Three- dimensional reconstruction of CT scan. (d) The preexisting plate was used for fixation of a vascularized scapula bone graft. (e) Postoper- ative clinical aspect of the scapula graft for reconstruction of the condyle and the ascending ramus. (f) Postoperative aspect with undisturbed mouth-opening ability. (Patient operated on together with Dr. Hartmann, MD, DDS, at Dortmund City Hospital.) 42. Microvascular Reconstruction of the Condyle and the Ascending Ramus 471 The fibula must be positioned in such a manner that the vascular pedicle again points toward the donor site vessels in the angular region. The vascular pedicle then runs along the inner or posterior side of the bone. In larger segments of the ascending ramus to be reconstructed, the proximal end of the fibula can be shaped round and placed in the condylar fossa. The desired angle of the mandibular graft is positioned at a region where the pedicle enters the bone. 19 Pedicle length can be increased by removing the proximal part of the fibula subperiostally (Fig- ure 42.12). A resorbable suture or wire positioned at the newly shaped condyle may be helpful for temporary fixation of the fibula in the temporal fossa by fixation of the suture or wire at the zygomatic arch. This type of fixation does not prevent caudal dislocation of the neocondyle postoperatively. When a fibula graft offers the best solution for bony reconstructions but an additional soft tissue pedicle is needed, the indication may be given to combine a fibula graft with a radial forearm flap, which also allows considerable indepen- dence in positioning of the bone and the soft tissues. A pre- condition for this procedure is an adequate number of recipient vessels. Although it may be considered to anastomose a fibula flap at the distal side of the radial forearm flap or vice versa, there may be an increased risk to lose two flaps with one vascular complication (Figure 42.13). a c b d FIGURE 42.10 (a) Clinical situation of a female patient following hemimandibulectomy and postoperative irradiation. (b) Osteocuta- neous parascapular flap for reconstruction of the posterior aspect of the mandible and volume augmentation. (c) Postoperative clinical aspect of the patient. (d) Postoperative x-ray. Bone graft fixation was performed with stable reconstruction plate because of the large flap volume. 472 R. Schmelzeisen and F.W. Neukam Discussion Indications for isolated condylar reconstruction with vascularized grafts are rare if existent at all. If given indications, microvascular reconstruction of the ascending ramus and condyle is a challenge for the reconstructive surgeon, although the general failure in lateral or posterior mandibular defects is significantly lower compared to anterior mandibular defects. 15 The graft selection has to be made with regard to the amount of bone necessary and the possible need for additional soft tissues. In our hands, the free fibula graft is to be regarded as the graft of choice for isolated bone defects. Addi- tional soft tissue defects in composite reconstructions may be tailored with flaps from the scapula region. In selected cases and with regard to the patient’s general condition and the recipient vessels, a two-flap reconstruction with a fibula and a radial forearm flap may be indicated. The aesthetic goal of posterior mandibular bone reconstruction is to provide a sufficient symmetrical sagittal chin projection and an adequate contouring of the mandibular angle. It has to be kept in mind that the distance between the condylar head and the angle is about 5 cm in general, and the skin projection of the angle is slightly below the earlobe. Lengthening of the ascending ramus may result in an unnat- ural location of the angle. This effect may also occur by a gradual caudal displacement of the neocondyle of the bone graft, although in most cases no functional impairment oc- curs. This effect does not occur if the condyle is still present and grafts can be sufficiently fixed to it. However, efforts should be made for the correct anatomic positioning of the bone graft in the temporomandibular fossa and to provide a bilateral support of mandibular motion. To overcome the tendencies for dislocation of the neocondyle and the ascending ramus, we more often keep patients in intermaxillary immobilization for 14 days in ac- cordance with other authors. 16,19,20,22 Afterward, postoperative functional therapy in cooperation with the Department of Physiotherapy is performed. We do not feel it is necessary to fix additional temporomandibular joint prostheses on the cranial aspect of a vascularized graft. 23 Also, mouth opening does not seem to depend greatly on positioning of the cranial aspect of a posterior bone graft, but rather on scar contraction of the soft tissues. Therefore, the FIGURE 42.11 Schematic drawing of harvesting of scapula graft for reconstruction of the ascending ramus and condyle. The tip of the scapula is positioned in the temporal fossa. Thus the vascular pedicle can point toward the angle or may also be positioned toward the midline if the recipient vessels are located on the contralateral side. 42. Microvascular Reconstruction of the Condyle and the Ascending Ramus 473 a d b c FIGURE 42.12 (a) The ipsilateral leg is chosen for reconstruction of a left-side defect. The vascular pedicle can be elongated by removal of proximal aspects of the fibula bone subperiostally. (b) To resem- ble the angle of the mandible, an osteotomy at the cranial and lin- gual aspect of the fibula has to be made. The whole length of the ascending ramus averages about 5 cm. (c) Note the outward deviation of the ascending ramus. (d) Intraoperative aspect of a fibula after distal and proximal osteotomy. [...]... 1988;82: 872 16 Motoki DS, Mulliken JB The healing of bone and cartilage Clin Plast Surg 1990; 17: 5 27 17 Zins JE, Whitaker LA Membranous versus endochondral bone: implications for craniofacial reconstruction Plast Reconstr Surg 1983 ;72 :77 8 18 Kusiak JF, Zins JE, Whitaker LA The early revascularization of membranous bone Plast Reconstr Surg 1985 ;76 :510 19 Sullivan PK, Smith J, Rozzelle AA Cranio-orbital... Hidalgo DA Fibula free flap mandibular reconstruction Head Neck Reconstr 1994;21(1):25–35 477 20 Hidalgo DA Condyle transplantation in free flap mandible reconstruction Plast Reconstr Surg 1994;93(4) :77 0 78 1 21 Swartz WM, Banis JC, Newton ED, Ramasastry SS, Jones NF, Acland R The osteocutaneous scapular flap for mandibular and maxillary reconstruction Plast Reconstr Surg 1986 ;77 (4):530–545 22 Urken ML,... temporomandibular joint surgery In: Walker RV, ed Transactions of the 3rd In- 5 6 7 8 ternational Conference on Oral Surgery London; 1 970 :148– 1 57 Kenett S Temporomandibular joint ankylosis: the rationale for grafting in the young patient J Oral Surg 1 973 ;31 :74 4 74 8 Matukas KJ, Szymela VF, Schmidt JF Surgical treatment of bony anklyosis in a child using a composite cartilage -bone iliac crest graft J... pterygoid process and reach a lateral target from a transoral approach or a central target from a lateral approach non–tooth-bearing bone, such as through the orbitozygomatic complex and frontal bone, can produce free segments that can be removed from the surgical field and reinserted Osteotomies Transmandibular and Transmaxillary Osteotomies that mobilize tooth-bearing bone or any segment of bone covered... male nasal bones Donor Sites The commonly used bone donor sites are the cranium, iliac crest, and ribs Each has advantages and disadvantages.16 Cranial bone has advantages when only bony support is needed The donor site is preferred because it is the least conspicuous and least painful, and it is close to the operative site Membranous bone demonstrates less resorption than endochondral bone when grafted... role of bone and cartilage grafts Clin Plast Surg 1989;16: 177 9 McCarthy JG, Wood-Smith D In: McCarthy JG, ed Plastic Surgery Philadelphia: WB Saunders: Rhinoplasty 3:1886–1890 10 Mayot D, Perrin C, Haas F, Brunet A Apport du gresson osseux de voute cranienne dans les septorhinoplasties d’addition Ann Oto-Laryngol 1990;1 07: 571 11 Sheen JH, Sheen AP Aesthetic Rhinoplasty St Louis: CV Mosby; 19 87 12 David... Neurosurgery 1991;29:411–416 Section V Craniomaxillofacial Corrective Bone Surgery 46 Orthognathic Examination Peter Ward-Booth It has been estimated that 1.2 million patients in the United States1 could benefit from surgical orthodontics It is important therefore that a patient with this potential problem should have a standard careful and complete examination Orthognathic surgery is no longer a “one-off... the graft and the recipient bed improves bone volume conservation.14 Second, rigid fixation of bone grafts has been shown to decrease resorption and thus theoretically improve long-term maintenance of the results.15 In addition, rigid fixation of the bone graft in a cantilever fashion allows distant and sometimes multidirectional support.1 ,7, 16 were significantly thicker than the female nasal bones from... Cranial nasal bone grafts Aesth Plast Surg 1989;13:285 6 Posnick JC, Seagle MB, Armstrong D Nasal reconstruction with full-thickness cranial bone grafts and rigid internal fixation through a coronal incision Plast Reconstr Surg 1990;86:894 7 Sullivan PK, Varma M, Rozzelle AA Optimizing bone graft nasal reconstruction: a study of nasal bone shape and thickness Plast Reconstr Surg (in press) 8 Ortiz-Monasterio... Reconstr Surg 1989;83:265– 271 5 Sullivan WG, Kawamoto HK Periorbital marginotomies: anatomy and application J Craniomaxillofac Surg 1989; 17: 206–209 6 Glassmann RD, Petty P, Vanderkolk C, Iliff N Techniques for improved visibility and lid protection in orbital explorations J Craniofac Surg 1990;1:69 71 7 Philips JH, Gruss JS, Wells MD, Chollet A Periosteal suspension of the lower eyelid and cheek following . (a,b) Sixteen-year-old female patient following hemimandibulectomy, full-dose chemotherapy, and radiotherapy for os- teogenic sarcoma of the left mandible. (c) For reconstruction, a vascularized. ascending ramus and condyle in a 50-year-old patient. Note the pencil-like shape of the severely atrophic bone graft with additional soft tissue shrinkage. F IGURE 42.3 (a,b) Twelve-year-old boy following. Conference on Oral Surgery. London; 1 970 :148– 1 57. 5. Kenett S. Temporomandibular joint ankylosis: the rationale for grafting in the young patient. J Oral Surg. 1 973 ;31 :74 4 74 8. 6. Matukas KJ,

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