Subject: Distraction Osteogenesis for Craniofacial Skeletal Deformities
Date: June 5, 2012
This Clinical Policy Bulletin expresses our determination of whether certain services or supplies are medically necessary. We have reached these conclusions based on a review of currently available clinical information including:
- Clinical outcome studies in the peer-reviewed published medical and dental literature
- Regulatory status of the technology
- Evidence-based guidelines of public health and health research agencies
- Evidence-based guidelines and positions of leading national health professional organizations
- Views of physicians and dentists practicing in relevant clinical areas
- Other relevant factors
We expressly reserve the right to revise these conclusions as clinical information changes, and welcome further relevant information.
Each benefits plan defines which services are covered, excluded and subject to dollar caps or other limits. Members and their dentists will need to consult the member's benefits plan to determine if any exclusions or other benefits limitations apply to this service or supply.
The conclusion that a particular service or supply is medically necessary does not guarantee that this service or supply is covered (that is, will be paid for by Aetna) for a particular member. The member's benefits plan determines coverage. Some plans exclude coverage for services or supplies that we consider medically necessary. If there is a discrepancy between this policy and a member's plan of benefits, the benefits plan will govern. In addition, coverage may be mandated by applicable legal requirements of a state, the federal government or CMS for Medicare and Medicaid members.
- Aetna considers distraction osteogenesis (distraction histogenesis) medically necessary for the correction of functional impairments accompanying the following congenital craniofacial skeletal deformities:
After review by Aetna's Oral and Maxillofacial Surgery (OMS) Unit, distraction osteogenesis may be considered medically necessary for correction of functional impairments accompanying other congenital craniofacial anomalies where it is determined that distraction osteogenesis can uniquely produce a degree of improvement unavailable with other standard techniques.
- Correction of severe micrognathia (such as accompanying Pierre Robin syndrome or Treacher Collins syndrome) in infants and children with airway obstruction
- Correction of hemifacial microsomia, in children with sufficient bone to allow for a corticotomy and/or osteotomy and placement of pins for external or internal distraction devices (that is, Pruzansky Grade I and IIa type mandibular deformity)
- Correction of severe congenital mandibular deficiency requiring lengthening of the mandible of greater than 10 mm (orthognathic surgery is able to correct smaller mandibular deformities)
- Widening of a narrow mandible or maxilla
- Lengthening of a short mandibular ramus (stretching of pterygomasseteric sling)
- Non-syndromic craniosynostosis -- coronal (bilateral or unilateral) or sagittal
- Syndromic craniosynostosis -- Apert, Crouzon, and Pfeiffer syndromes
- Cleft lip and palate.
- Aetna considers distraction osteogenesis experimental and investigational for acquired craniofacial defects (for example, reconstruction of defects following tumor (for example, osteosarcoma) resection, or ablative head and neck surgery), obstructive sleep apnea, and all other craniofacial indications because of insufficient evidence regarding the clinical value of this approach for these indications.
- Orthognathic Surgery
- Ilizarov Method for Distraction Osteosynthesis
Orthognathic surgery is the surgical correction of skeletal anomalies or malformations involving the midface, mandible and maxilla. These malformations may be present at birth, or may become evident as the patient grows and develops. Jaw malformations can cause chewing and eating difficulties, abnormal speech patterns, early loss of teeth, and disfigurement and dysfunction of the maxilla and mandible. Malocclusion may be caused by a deficiency or excess of bony tissue in one or both jaws, or by trauma to the facial bones.
In orthognathic surgery, an osteotomy is made in the affected jaw, and the bones are repositioned in a more physiologic alignment. Generally, the bones are held in their new positions with plates, screws and wires. The patient may also need arch bars placed on both jaws to add stability (a procedure called intermaxillary fixation). For patients with deformities affecting both jaws, either simultaneous or staged osteotomies may be undertaken to achieve correction. Patients with deficient bone tissue may require grafts from their ribs, hips or skull. Alloplastic replacement of missing bone may also be required.
Indications for orthognathic surgery include:
- mandibular prognathism
- mandibular retrognathia
- maxillary excess
- maxillary deficiency
- apertognathia (open bite deformity)
In some cases, adjunctive procedures such a reconstructive rhinoplasty, malar and chin osteoplasty, and bone grafting are needed to correct deformities. However these procedures require evaluation by the Oral and Maxillofacial surgery unit to determine coverage. These adjunctive procedures are typically considered cosmetic in nature.
Distraction Osteogenesis (DO), initially developed by Ilizarov for limb lengthening has recently been applied to the correction of severe congenital or acquired craniofacial deformities as an early alternative to orthognathic surgery. Distraction Osteogenesis involves the lengthening and reshaping of deformed bone by surgical fracture and gradual separation of bony segments. The surgeon lengthens and reshapes deformed bone by surgically fracturing the bone and slowly separating (distracting) the resultant segments with specially fabricated hardware. The bony fragments are held in place during the first week following surgical fracture to allow callus to form between the fragments. During the next several weeks, the fragments are gradually separated at a rate of 1 to 2 millimeters per day, up to a predetermined length (for example, 20 days for 20 millimeters or 5/8 inches). The bone segments are moved gradually to allow callus formation and adaptation of fibromuscular attachments. Once the desired length and shape is achieved, the hardware is left in place for an additional six weeks until the newly formed bone calcifies.
The specially fabricated hardware used for the distraction process can be internal or external. Advantages of external devices include ease of placement and removal. In addition, some external devices allow multidimensional control. External devices, however, are very conspicuous and are more likely to cause traction scars than internal devices. Internal devices are less visible than external devices, and directly transmit force to the bone. Internal devices, however, are only unidirectional and require a subsequent surgical procedure for their removal.
The primary advantage claimed in connection with distraction osteogenesis is that it allows major reshaping of the facial bones without bone grafts or jaw wiring. Proponents claim that distraction osteogenesis may be safer than other methods of facial reconstruction, since it can involve less blood loss and a lower risk of infection. However, according to available literature, distraction osteogenesis has several drawbacks. If the bone ends are moved apart too slowly, callus may calcify too soon, preventing further distraction. If the bone ends are moved apart too rapidly, callus may become too fibrous and fail to mature into solid bone. Therefore, the rate and rhythm of distraction is important to the quality and quantity of bone that is formed.
The published literature regarding the effectiveness of distraction osteogenesis for craniofacial anomalies has focused on its use in repair of congenital conditions in young children. The published clinical literature on distraction osteogenesis for developmental and acquired craniofacial deformities is more limited, and consists primarily of case series reporting on its technical feasibility, perioperative morbidity, and short-term outcomes. Orthognathic surgery is the established method of correcting developmental mandibular deficiencies, maxillary deficiencies and other developmental and acquired craniofacial deformities. More investigation is necessary to refine distraction osteogenesis technique, to help define its role in craniofacial surgery, and to improve the design and reliability of distraction devices in repairing developmental and acquired deformities in older children and adults whose growth is at or near completion. Moreover, there are insufficient published data on the long-term effectiveness of this procedure for these indications, especially on the rate of skeletal relapse.
According to a position statement from the American Association of Oral and Maxillofacial Surgeons (AAOMS, 2003), “the indications for distraction involving the jaws are limited to conditions in which this technique may be uniquely able to produce significant improvement over more traditional therapy.” According to the AAOMS (2003), examples of these situations are as follows:
- Severe deficiency of either jaw with early correction indicated, for example, an infant with Pierre Robin with mandibular deficiency so severe that tracheostomy is required and advancement of the mandible is the only way to correct an obstructive situation.
- Severe mandibular deficiency requiring lengthening of the mandible of greater than 10 mm. Growth modification via orthodontics generally produces no more than 5 mm differential growth and conventional orthognathic procedures become more difficult and less predictable when greater than 8 to 10 mm advancement is needed.
- Need for lengthening of a short mandibular ramus. According to the AAOS, the nature of distraction osteogenesis is well suited for stretching of the pterygomasseteric sling, which is not easily overcome by conventional procedures.
Narrow mandible that must be widened. There has been little success in widening the mandible with conventional surgery prior to the advent of distraction. Distraction techniques offer a better way to address this problem.
The AAOMS guidelines also list alveolar deficiency among examples of established indications for distraction osteogenesis for craniofacial anomalies. However, there is insufficient published evidence of the effectiveness of distraction osteogenesis for vertical augmentation of the alveolar ridge in comparison with grafting techniques for this indication.
The AAOMS guidelines list “[w]idening of the maxilla in an adult” among established indications for distraction osteogenesis. However, surgically assisted palatal expansion, which is analogous to distraction osteogenesis, has been utilized to overcome this problem for decades with very desirable and stable results.
AAOMS guidelines note that, “[a]s with any procedure, distraction osteogenesis should be utilized primarily when superior results can be achieved compared to conventional techniques” (AAOMS, 2003).
Although the AAOMS guidelines do not distinguish between congenital and developmental and acquired conditions, the published evidence to date has focused on repair of congenital conditions. There is insufficient evidence of the effectiveness of distraction osteogenesis for developmental and acquired craniofacial anomalies.
Schreuder et al (2007) noted that bilateral sagittal split osteotomy (BSSO) and distraction osteogenesis are the most common techniques currently applied to surgically correct mandibular retrognathia. These investigators reviewed the literature on BSSO and mandibular distraction osteogenesis with emphasis on the influence of age and post-surgical growth, damage to the inferior alveolar nerve, and post-surgical stability and relapse. Although randomized clinical trials are lacking, some support was found in the literature for distraction osteogenesis having advantages over BSSO in the surgical treatment of low and normal mandibular plane angle patients needing greater advancement (greater than 7 mm). In all other mandibular retrognathia patients the treatment outcomes of distraction osteogenesis and BSSO seemed to be comparable. Distraction osteogenesis is accompanied by greater patient discomfort than BSSO during and shortly after treatment, but it is unclear if this has any consequences in the long term. There is a need for randomized clinical trials comparing the two techniques in all types of mandibular retrognathia, in order to provide evidence-based guidelines for selecting which retrognathia cases are preferably treated by BSSO or distraction osteogenesis.
Sacco and Chepeha (2007) stated that earlier work has reported encouraging results regarding the translation of distraction osteogenesis from animal studies to human uses, with particular success in the unradiated setting. The major challenge surrounding the use of this technology in head and neck oncological reconstruction will be the effect of radiotherapy on the regenerate bone in patients who have received or will need radiotherapy as part of their treatment. Although distraction osteogenesis provides an attractive option for reconstructing mandibular defects, large human studies are needed to further evaluate the use of this technology and its role in the treatment for mandibular neoplasms.
Ow and Cheung (2008) stated that mandibular distraction osteogenesis has been used effectively to treat syndromic craniofacial deformities. In recent years, its scope of application has widened to include treatment of airway obstruction in adults and children as well as non-syndromic class II mandibular hypoplasia. So far, there has been no evidence-based review of mandibular distraction osteogenesis for mandibular lengthening.
These investigators carried out a meta-analysis of mandibular distraction osteogenesis. Two rounds of searches were performed by two independent assessors. The first-round PubMed search used the keywords "mandible" and "distraction osteogenesis.” In the second-round search, the reference lists of the articles were retrieved. For both rounds, abstracts and then full articles were reviewed and selected on the basis of a set of inclusion and exclusion criteria. The 178 retrieved articles yielded 1185 mandibular distraction osteogenesis patients: 539 received unilateral mandibular distraction osteogenesis and 646 received bilateral mandibular distraction osteogenesis. Mandibular distraction osteogenesis was reported to improve facial asymmetry and retrognathia (50.1 %), correct the slanted lip commissure (24.7 %), and improve or level the mandibular occlusal plane (11.1 %) in unilateral asymmetry cases, whereas bilateral mandibular distraction osteogenesis was shown to be effective in preventing tracheostomies for 91.3 % of neonates or infants with respiratory distress, and in relieving symptoms of obstructive sleep apnea for 97.0 % of children and 100 % of adult patients. The authors concluded that mandibular distraction osteogenesis is effective in treating craniofacial deformities, but further clinical trials are needed to evaluate the long-term stability and to compare the treatment with conventional treatment methods, especially in cases of obstructive sleep apnea or class II mandibular hypoplasia.
|CPT codes covered if selection criteria are met:
||Application of multiplane (pins or wires in more than one plane), unilateral, external fixation system (for example, Ilizarov, Monticelli type)
||Adjustment or revision of external fixation system requiring anesthesia (for example, new pin(s) or wire(s) and/or new ring(s) or bar(s))
||Removal, under anesthesia, of external fixation system
||Application of multiplane (pins or wires in more than one plane), unilateral, external fixation with stereotactic computer-assisted adjustment (for example, spatial frame), including imaging; initial and subsequent alignment(s), assessment(s), and computation(s) of adjustment schedule(s)
||exchange (for example, removal and replacement) of strut, each
|Other CPT codes related to the CPB:
||Application of interdental fixation device for conditions other than fracture or dislocation, includes removal
|21120 - 21196
||Repair, revision, and/or reconstruction bones of face
||Osteotomy, maxilla, segmental (for example, Wassmund or Schuchard)
||Graft, bone; nasal, maxillary or malar areas (includes obtaining graft)
||Reconstruction of mandibular condyle with bone and cartilage autografts (includes obtaining grafts) (for example, for hemifacial microsomia)
|30400 - 30462
|42200 - 42225
|Other HCPCS codes related to the CPB:
|D7946 - D7949
||LeFort procedures I, II, or III
|ICD-9 codes covered if selection criteria are met:
|524.01 - 524.09
||Major anomalies of jaw size
|524.11 - 524.19
||Anomalies of relationship of jaw to cranial base
|524.21 - 524.23
||Angle's class I, II, III malocclusion
||Dentofacial functional abnormalities
||Certain congenital musculoskeletal deformities of skull, face and jaw
||Anomalies of skull and face bones
|ICD-9 codes not covered for indications listed in the CPB:
||Obstructive sleep apnea (adult) (pediatric)
|738.10 - 738.19
||Other acquired deformity of head [acquired craniofacial defects]
|Other ICD-9 codes related to the CPB:
||Other loss of teeth
||Other specified diseases of jaws
||Feeding problems in newborn
||Feeding difficulties and mismanagement
||Other speech disturbance
||Injury of face and neck
The above policy is based on the following references:
- Van Sickels JE. Distraction osteogenesis versus orthognathic surgery. Am J Orthod Dentofacial Orthop. 2000;118(5):482-484.
- Rachmiel A, Aizenbud D, Eleftheriou S, et al. Extraoral vs. intraoral distraction osteogenesis in the treatment of hemifacial microsomia. Ann Plast Surg. 2000;45(4):386-394.
- Gateno J, Teichgraeber JF, Aguilar E. Distraction osteogenesis: A new surgical technique for use with the multiplanar mandibular distractor. Plast Reconstr Surg. 2000;105(3):883-888.
- Oda T, Sawaki Y, Ueda M. Experimental alveolar ridge augmentation by distraction osteogenesis using a simple device that permits secondary implant placement. Int J Oral Maxillofac Implants. 2000;15(1):95-102.
- Marquez IM, Fish LC, Stella JP. Two-year follow-up of distraction osteogenesis: Its effect on mandibular ramus height in hemifacial microsomia. Am J Orthod Dentofacial Orthop. 2000;117(2):130-139.
- van Strijen PJ, Perdijk FB, Becking AG, et al. Distraction osteogenesis for mandibular advancement. Int J Oral Maxillofac Surg. 2000;29(2):81-85.
- Jensen OT. Distraction osteogenesis and its use with dental implants. Dent Implantol Update. 1999;10(5):33-36.
- Tillery DE Jr. Advances in orthognathic surgery. Dent Today. 1998;17(8):90-92.
- Gaggl A, Schultes G, Karcher H. Distraction implants: A new operative technique for alveolar ridge augmentation. J Craniomaxillofac Surg. 1999;27(4):214-221.
- Cohen SR, Burstein FD, Williams JK. The role of distraction osteogenesis in the management of craniofacial disorders. Ann Acad Med Singapore. 1999;28(5):728-738.
- Diner PA, Tomat C, Soupre V, et al. Intraoral mandibular distraction: Indications, technique and long-term results. Ann Acad Med Singapore. 1999;28(5):634-641.
- Mehrara BJ, Longaker MT. New developments in craniofacial surgery research. Cleft Palate Craniofac J. 1999;36(5):377-387.
- Figueroa AA, Polley JW. Management of severe cleft maxillary deficiency with distraction osteogenesis: Procedures and results. Am J Orthod Dentofac Orthop. 1999;115:1-12.
- Guerrero CA, Bell WH, Contasti GI, et al. Mandibular widening by intraoral distraction osteogenesis. Br J Oral Maxillofac Surg. 1997;35:383-392.
- Liou EJ, Huang CS. Rapid canine retraction through distraction of the periodontal ligament. Am J Orthod Dentofac Orthop. 1998;114:372-382.
- Samchukov ML, Cope JB, Harper RP, et al. Biomechanical considerations of mandibular lengthening and widening by gradual distraction using a computer model. J Oral Maxillofac Surg. 1998;56(1):51-59.
- Mommaerts MY. Reliability and validity of a backlighted digitizer when used for craniofacial measurements. J Craniofac Surg. 1997;8:222-228.
- Klein C, Howaldt HP. Correction of mandibular hypoplasia by means of bidirectional callus distraction. J Craniofac Surg. 1996;7:258-266.
- Swennen G, Schliephake H, Dempf R, et al. Craniofacial distraction osteogenesis: A review of the literature: Part 1: Clinical studies. Int J Oral Maxillofac Surg. 2001;30(2):89-103.
- Swennen G, Dempf R, Schliephake H. Cranio-facial distraction osteogenesis: A review of the literature. Part II: Experimental studies. Int J Oral Maxillofac Surg. 2002;31(2):123-135.
- Imola MJ, Hamlar DD, Thatcher G, et al. The versatility of distraction osteogenesis in craniofacial surgery. Arch Facial Plast Surg. 2002;4(1):8-19.
- Patel PK, Han H. Craniofacial, distraction osteogenesis. eMedicine Plastic Surgery, Topic 459. Omaha, NE: eMedicine.com; updated February 1, 2002.
- Imola MJ. Craniofacial distraction osteogenesis. eMedicine Otolaryngology and Facial Plastic Surgery, Topic 702. Omaha, NE: eMedicine.com; updated May 14, 2002.
- American Association of Oral and Maxillofacial Surgeons (AAOMS). Distraction osteogenesis. Statements by the American Association of Oral and Maxillofacial Surgeons Concerning the Management of Selected Clinical Conditions and Associated Clinical Procedures. Rosemont, IL: AAOMS; July 2003.
- Shaw WC, Mandall NA, Mattick CR. Ethical and scientific decision making in distraction osteogenesis. Cleft Palate Craniofac J. 2002;39(6):641-645.
- Denny AD, Kalantarian B, Hanson PR. Rotation advancement of the midface by distraction osteogenesis. Plast Reconstr Surg. 2003;111(6):1789-1799; discussion 1800-1803.
- Figueroa AA, Polley JW, Friede H, Ko EW. Long-term skeletal stability after maxillary advancement with distraction osteogenesis using a rigid external distraction device in cleft maxillary deformities. Plast Reconstr Surg. 2004;114(6):1382-1392; discussion 1393-1394.
- Shirai T, Tsuchiya H, Yamamoto N, et al. Successful management of complications from distraction osteogenesis after osteosarcoma resection: A case report. J Orthop Sci. 2004;9(6):638-642.
- Raghoebar GM, Jansma J, Vissink A, Roodenburg JL. Distraction osteogenesis in the irradiated mandible. A case report. J Craniomaxillofac Surg. 2005;33(4):246-250.
- Matsubara H, Tsuchiya H, Sakurakichi K, et al. Distraction osteogenesis of a previously irradiated femur with malignant lymphoma: A case report. J Orthop Sci. 2005;10(4):430-435.
- Rubio-Bueno P, Naval L, Rodriguez-Campo F, et al. Internal distraction osteogenesis with a unidirectional device for reconstruction of mandibular segmental defects. J Oral Maxillofac Surg. 2005;63(5):598-608.
- Erler K, Yildiz C, Baykal B, Reconstruction of defects following bone tumor resections by distraction osteogenesis. Arch Orthop Trauma Surg. 2005;125(3):177-183.
- Kunkel M, Wahlmann U, Reichert TE, et al. Reconstruction of mandibular defects following tumor ablation by vertical distraction osteogenesis using intraosseous distraction devices. Clin Oral Implants Res. 2005;16(1):89-97.
- Enislidis G, Fock N, Ewers R. Distraction osteogenesis with subperiosteal devices in edentulous mandibles. Br J Oral Maxillofac Surg. 2005;43(5):399-403.
- Cano J, Campo J, Moreno LA, Bascones A. Osteogenic alveolar distraction: A review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006;101(1):11-28.
- Chanchareonsook N, Samman N, Whitehill TL. The effect of cranio-maxillofacial osteotomies and distraction osteogenesis on speech and velopharyngeal status: A critical review. Cleft Palate Craniofac J. 2006;43(4):477-487.
- Sacco AG, Chepeha DB. Current status of transport-disc-distraction osteogenesis for mandibular reconstruction. Lancet Oncol. 2007;8(4):323-330.
- Ow AT, Cheung LK. Meta-analysis of mandibular distraction osteogenesis: Clinical applications and functional outcomes. Plast Reconstr Surg. 2008;121(3):54e-69e.
- Genecov DG, Barceló CR, Steinberg D, et al. Clinical experience with the application of distraction osteogenesis for airway obstruction. J Craniofac Surg. 2009;20 Suppl 2:1817-1821.
- Verstraaten J, Kuijpers-Jagtman AM, Mommaerts MY, et al.; Eurocran Distraction Osteogenesis Group. A systematic review of the effects of bone-borne surgical assisted rapid maxillary expansion. J Cranio-Maxillo-Facial Surg. 2010;38(3):166-174.
Original policy: November 4, 2004
Updated: September 25, 2006, August 26, 2008; November 16, 2009; January 20, 2011
Revised: June 5, 2012
Medical Bulletin #0549
: September 20, 2011
# 0549 has been revised to state that enhancement of bone formation by means of bone morphogenetic proteins and local injection of bone marrow aspirate and platelet gel at the osteotomy site during distraction osteogenesis is considered experimental and investigational.