ORIGINAL ARTICLE Local resection of the mass to treat the osteochondroma of the mandibular condyle: Indications and different methods with 38-case series Min-Jie Chen, MD, 1 Chi Yang, MD, 1 * Ya-Ting Qiu, MD, 1 Dong-Mei He, MD, 1 Qin Zhou, DDS, 1 Dong Huang, DDS, 1 Hui-Min Shi, MD 2,3 1 Department of Oral and Maxillofacial Surgery, Ninth People s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China, 2 Department of Oral and Maxillofacial Surgery, First Teaching Hospital of Xinjiang Medical University, Urumuqi Xinjiang, China, 3 Department of Radiology, Ninth People s Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China. Accepted 28 September 2012 Published online 18 March 2013 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/hed.23218 ABSTRACT: Background. Local resection of the mass was reported to treat the condylar osteochodroma in some cases. The purpose of this study was to evaluate the feasibility and the indications of the local resection. Methods. In all, 47 patients with osteochondroma of the mandibular condyle were treated from January 2002 to March 2012. The decision to perform local resection depended on 2 factors: there was a stalk existing between the mass and the condyle, and the condylar surface was involved less than 1/2. Results. Local resection of the mass was performed in 38 cases (80.1%). These masses were removed by 4 methods: direct removal (18 cases), pushed-out by a screw and steel wire (14 cases), excision in multiple pieces (3 cases), and temporary osteotomy of the zygomatic arch (3 cases). In the follow-up period, there was no recurrence. Conclusion. Local resection of the mass was a more conservative procedure to treat the solitary osteochondroma with a stalk. VC 2013 Wiley Periodicals, Inc. Head Neck 36: 273 279, 2014 KEY WORDS: osteochondroma, mandibular condyle, local resection of the mass, indication, method INTRODUCTION The World Health Organization defines the osteochondroma as a "cartilage-capped bony protrusion on the external surface of bone. It represents approximately 35% to 50% of all benign bone tumors and 8% to 15% of all primary bone tumors. 1 The most common sites of the craniofacial region are the mandibular condyle and the coronoid process. In 2010, Ord et al 2 identified 67 cases of this tumor to be documented. Roychoudhury et al 3 made it more accurate to say that by 2011 at least 108 cases had been reported in the English-language literature. The number of single case reports is 48; the largest case series is 17. 4 Surgical resection is an acceptable treatment. Total condylectomy and conservative subtotal condylectomy were often used in the treatment of the condylar osteochondroma. Immediate or delayed reconstruction was performed by This article was published online on 18 March 2013. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected [16 December 2013]. *Corresponding author: C. Yang, Department of Oral and Maxillofacial Surgery, Ninth People s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China. E-mail: yangchi63@hotmail.com Contract grant sponsor: National Natural Science Foundation of China; contract grant number: 81070848; contract grant sponsor: Program for Innovative Research Team of Shanghai Municipal Education Commission. several methods, such as sagittal split ramus osteotomy (SSRO) and superior advancement, a costchondral graft (CCG) or iliac bone graft. Due to its benign nature, there was an extremely low recurrence. 5 However, could the surgery have been even more conservatively performed? Cottrell 6 proposed to save as much of the condyle as possible. Some single case reports were found to use local resection of the mass. 7 11 There were some queries about the procedure of local resection of the mass, such as: (1) Will it result in a high rate of recurrence? (2) What kind of condylar osteochondroma was appreciated for local resection of the mass? and (3) How is the mass released if it was huge and deep? There were no large case series to answer these questions. Presented here is a report of 38 cases of the osteochondroma of the mandibular condyle treated by local resection of the mass with the condylar head preserved in our unit from January 2002 to March 2012. The purpose of this report was to discuss the feasibility and the indication of local resection of the mass. The methods of resection were also introduced. MATERIALS AND METHODS The records of 47 patients with osteochondroma of the mandibular condyle at our unit from January 2002 to March 2012 were retrospectively analyzed. Local resection of the mass was performed in 38 cases (80.1%), total condylectomy in 5 cases (10.6%), and subtotal condylectomy in 4 cases (8.5%). CCG reconstruction, temporary zygomatic arch osteotomy, or orthognathic surgical HEAD & NECK DOI 10.1002/HED FEBRUARY 2014 273
CHEN ET AL. TABLE 1. General characteristics of the patients who had local resection of the mass performed. TABLE 2. Operative findings of the patients who had local resection of the mass performed. Characteristic Value Characteristic Value Age at surgery, y Median 41.5 Average 43.7 Sex, n (%) Male 10 (26.3%) Female 28 (73.7%) Side of symptom, n (%) Right 22 (57.9%) Left 16 (42.1%) Preoperative duration of symptom, y Median 1.0 Average 2.93 Symptoms, n (%) Mandible asymmetry 26 (68.4%) Maxilla and mandible asymmetry 5 (13.2%) Preauricular pain 13 (34.2%) Preauricular swelling 17 (44.7%) Ipsilateral hearing loss 2 (5.3%) Recurrent luxation 2 (5.3%) Joint noise 17 (44.7%) Limitation of the open mouth (30 mm) 18 (47.4%) Malocclusion 31 (81.6%) procedures, if indicated, were then concomitantly performed to optimize occlusion, function, and esthetics. The study protocol was approved by and in accord with the recommendations of the human research committee at our institution. Prior to scanning and surgical procedures all patients gave written consent. In all, 38 cases with local resection of the mass and preservation of the condylar head were the core concerns of this report. The decision to perform local resection depended on 2 factors: there was a stalk existing between the mass and the condylar head, and the condylar surface was involved less than half. The variables studied were age, sex, side, duration, symptoms, and treatment. Panoramic radiographs, standardized frontal and lateral cephalometric tomograms, and CT scans before surgery, immediately after surgery, and at the follow-up period were assessed. The diagnosis of osteochondroma was confirmed by histopathologic examination. The facial symmetry, temporomandibular joint (TMJ) pain, mouth opening, occlusion, and radiologic examination were evaluated during the follow-up period. RESULTS The general characteristics of 38 patients performed local resection of the mass are presented in Table 1. Gender predilection (male:female) was 1:2.8. Right:left side predilection was 1.4:1. Only 2 cases had trauma history. Age range was 21 to 74 years, with a mean of 43.7 years. Preoperative duration was 2 months to 15 years, with a mean of 2.93 years. The first symptom noticed was a gradual development of asymmetry and chin deviation, then followed by TMJ dysfunction, swelling, and pain. In all 38 patients, CT revealed the mass protruding from the condyle with less than half of the condyle involved. Location of the mass, n (%) Anterior/anteromedial 25 (65.8%) Posterior/posteromedial 3 (7.9%) Medial 8 (21.1%) Lateral 2 (5.3%) Treatment, n (%) Local resection of the mass 33 (86.8%) Local resection with temporary 3 (7.9%) zygomatic arch osteotomy Local resection with bilateral sagittal 1 (2.6%) split ramus osteotomy Local resection with genioplasty 1 (2.6%) Method of removal of the mass, n (%) Direct removal 18 (47.4%) Distraction by a screw and steel wire 14 (36.8%) Excision in multiple pieces 3 (7.9%) Temporary zygomatic arch osteotomy 3 (7.9%) In accord with CT scans and the operative findings, the location of the mass relative to the condylar head was as follows (Table 2): anterior/anteromedial in 25 cases (65.8%), posterior/posteromedial in 3 cases (7.9%), medial in 8 cases (21.1%), and lateral in 2 cases (5.3%). In 33 patients (86.8%) local resection of the mass only was performed. One case was combined with bilateral SSRO; 1 case was combined with genioplasty. FIGURE 1. Reoperated patient with residue stalk (arrow). 274 HEAD & NECK DOI 10.1002/HED FEBRUARY 2014
FEASIBILITY AND INDICATIONS OF THE LOCAL RESECTION (see Figure 1). The residual stalk was removed to correct the stable occlusion and to avoid the recurrence. Among 38 patients, stable occlusion or minimal occlusion discrepancy was regained immediately after the operation in 26 patients, maxillomandibular elastic bands were applied in 7 patients, and orthodontic therapy was done in 1 patient. However, 4 patients without good occlusion refused to do any subsequent therapy. The follow-up averaged 23.8 months with a range of 1 to 84 months. Twelve cases were lost to follow-up; 6 patients were followed up for at least 5 years; 10 were 1 to 2 years postoperatively; and 10 were less than half a year. TMJ pain, swelling, and hearing loss disappeared. The facial symmetry was almost regained in 34 cases. In the 26 patients who were followed-up, CT scans were examined every year during the follow-up period. No recurrence was encountered except roughness of the bony cut-line occurred in 2 cases. FIGURE 2. Preoperative appearance. (A) Frontal view showing elongation of the left mandible and deviation of the chin to the right. (B) Deviation of the mandibular dental midline to the right by 6 mm. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.] These masses were removed by 4 methods (Table 2): direct removal in 18 cases, pushed-out by a screw and steel wire in 14 cases, excision in multiple pieces in 3 cases, and temporary osteotomy of the zygomatic arch with masseter muscle attachment in 3 cases. If the mass was too big to be grasped by a forceps, it could be pushed out with assistance of a screw and steel wire. Before fixing the screw, the direction and the length of the screw should be evaluated in accord with the dimension of the mass. The screw should not be longer than the dimension of the mass to avoid damaging the maxilla artery. An obvious differentiable stalk could be found in all of the 38 cases. The largest tumor was 4 3 2 cm and the smallest was 1 1 0.5 cm. Two patients were operated on twice because the residual stalk was found by the immediate postoperative CT scan FIGURE 3. Preoperative CT scans. (A) Axial CT scan showing the mass arising from the medial portion of the condylar surface (arrow). (B) Coronal CT scan showing the mass extending superomedially into the infratemporal fossa (arrow). HEAD & NECK DOI 10.1002/HED FEBRUARY 2014 275
CHEN ET AL. FIGURE 4. Operative photographs. (A) The condyle (white arrow) was pushed infra-anteriorly to expose the mass (thick dark arrow). (B) The cutline (thin black arrow) on the stalk of the mass. (C) The mass was released with preservation of the condyle. (D) The gross specimen with multiple nodes. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.] Case presentation A 46-year-old woman presented in 2010 with complaint of facial asymmetry and malocclusion. Examination of the patient revealed elongation of the left mandible with deviation of the chin to the right (Figure 2A). Her mouth opening was 10 mm, and mandibular dental midline was deviated to the right by 6 mm. There was a left posterior open bite and a right cross bite (Figure 2B). CT scan showed the mass extended superomedially into the infratemporal fossa (Figures 3A, 3B). Preoperative model analysis showed that a good occlusion could be obtained. The patient was operated on under general anesthesia via a preauricular and infratemporal approach to the joint. The superficial temporal fascia and periosteum overlying the zygomatic arch were incised, leaving the superficial neurovascular structures behind. The inferior compartment was opened. The insertion of the lateral pterygoid muscle was cut to expose the tumor. A screw twining with a steel wire was inserted into the mass (Figure 4A). The stalk of the mass was cut with a motor saw (Figure 4B). The mass with the screw-steel elevator was freed and dissected from the surrounding soft tissue (Figures 4C, 4D). Histopathologic examination of the resected specimen revealed a thickened cartilaginous cap over the mass and islands of subchondral ossification (see Figure 5), thereby confirming the diagnosis of osteochondroma. Maxillomandibular elastic bands were applied postoperatively for 1 month. By 1 year after the 276 HEAD & NECK DOI 10.1002/HED FEBRUARY 2014
FEASIBILITY AND INDICATIONS OF THE LOCAL RESECTION DISCUSSION Osteochondroma is the most common benign bone tumor. Osteochondroma of mandibular condyle has been reported earlier under different confusing terminologies, such as osteoma, unilateral hypertrophy of the mandibular condyle, benign hyperplasia, and exostosis. The publication by Kanthak and Harkins, titled Unilateral Hypertrophy of the Mandibular Condyle Associated with Chondroma, has been designated as the first case in all the literature reviews. 6 Until 2011, in all there were 108 cases of mandibular condylar osteochondroma in the Englishlanguage literature. 3 Our report is the largest series of osteochondroma of mandibular condyle. Compared with Roychoudhury s review, 3 correlation of trauma was not obvious in our report (2/38), and the occurrence was much likely trend to the female (28/ 38). Clinical symptomatology of patients with osteochondromas may include 1 or more of the following: vertical elongation of the mandible on the affected side, progressively increasing facial asymmetry, malocclusion, TMJ dysfunction, swelling, pain, and, rarely, hearing loss. In consideration of the benign nature of the tumor and its extremely low likelihood of recurrence, the aim of treatment was excision of the tumor and a swing back of the mandible to near normal occlusion and facial midline correction. In the literature, there are 3 kinds of treatment to the mandibular condylar osteochondroma. Traditional treatment of 76.67% 12 reported cases was the radical resection of the tumor and total condylectomy, 3,13 17 with/without reconstruction of superiorly repositioned vertical ramus, 1,2,4,18 21 CCG, 2,22 or iliac bone harvest. 23 CCG and iliac bone harvest need a donor invasion. Some reports introduced a conservative subtotal condylectomy. 3,5,24 Although the shape of the condyle would be similar to that of the normal one, the loss of the superficial chondrocytes increased the risk of osteoarthritis. A few case reports chose local resection of the mass. Due to its conservative superiority, we accepted it as our basic treatment. Although being worried about the added risk of recurrence, Cottrell 6 proposed to save as much of the condyle as possible and to base the excision on the clinical apparent margin with removal of the cartilage cap. Before Cottrell, Iizuka et al 7 in 1996 (1 case), 7 Koole et al 8 in 1996 (1 case), Rivera et al 9 in 1998 (1 case), Kurita et al 10 in 1999 (1 case), and Aydin et al 11 in 2001 (2 cases) had preferred excision of the mass and the involved FIGURE 5. Histopathologic examination showing a thickened cartilaginous cap (black arrow) and islands of subchondral ossification (white arrow) (hematoxylin and eosin stain, original magnification 200). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.] surgery, the patient demonstrated good aesthetic and functional stability (Figures 6A, 6B). CT revealed no recurrence (Figures 7A, 7B). FIGURE 6. Postoperative appearances 1 year after the surgery. (A) Frontal view showing the correction of asymmetry. (B) Restored occlusion with midline correction. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.] HEAD & NECK DOI 10.1002/HED FEBRUARY 2014 277
CHEN ET AL. only 3 cases recurred out of the condylar osteocondroma, there was no recurrence found in the reports of local resection. Our excellent follow-up results supported the feasibility of the local resection. Axial and coronal CT scans were the important foundation to decide the indication of local resection of the mass. Our radiologic indications include 2 conditions. The first is that a stalk exists between the mass and the condylar head and the second is that the normal condylar surface is more than half. Preoperative CT scans are also necessary to decide the direction and the method of the resection. Immediate postoperative CT scans can show whether the resection of the mass is complete or incomplete. We had 2 patients who suffered from incomplete resection. CT scans immediately after the surgery revealed the mistake. The remaining mass was resected under local anesthesia before the patient went back home. CONCLUSION The use of the technique of local resection of the mass is a more conservative procedure to treat the solitary osteochondroma with a stalk. It could be accomplished by direct removal, distraction by a screw and steel wire, excision in multiple pieces, and temporary osteotomy of the zygomatic arch with masseter muscle attachment. This procedure gives excellent results with regard to facial symmetry, occlusion, and TMJ function. Note added in proof Maimaitituxun Tuerdi, MD, was erroneously listed as an author in the initial online publication. The current version of the article includes the correct author list. REFERENCES FIGURE 7. Postoperative CT scans showing no recurrence (arrow). (A) Axial CT scan. (B) Coronal scan. portion of the condyle. In our unit, 38 cases were performed on local resection of the mass. The advantages were as follows: preservation of the condylar head, which was important to keep the vertical height and the TMJ function; minimal invasion; simple manipulation. All patients did not need additional reconstruction of the condyle. The good results of the facial symmetry and stable occlusion were found. However, some reports argued that the disadvantages of the local resection were the difficult removal of the big or deep masses and incomplete resection of the mass, resulting in recurrence. In our report, distraction by a screw and steel wire were used in 14 cases, excision in multiple pieces in 3 cases, and temporary osteotomy of the zygomatic arch in 3 cases. So, the difficulties of removing the mass from the deeper structures could be overcome by distraction with a screw and steel wire, excising in multiple pieces, or temporary zygomatic arch osteotomy. Although the recurrence rate for the solitary osteochondroma in long bones is 2% 5,6 and 1. Karras SC, Wolford LM, Cottrell DA. Concurrent osterchondroma of the mandible condyle and ipsilateral cranial base resulting in TMJ ankylosis. Report of a case and review of the literature. J Oral Maxillofac Surg 1996; 54:640 646. 2. Ord RA, Warburton G, Caccamese JF. Osteochondroma of the condyle: review of 8 cases. Int J Oral Maxillofac Surg 2010;39:523 528. 3. Roychoudhury A, Bhatt K, Yadav R, Bhutia O, Roychoudhury S. Review of osteochondroma of mandibular condyle and report of a case series. J Oral Maxillofac Surg 2011;69:2815 2823. 4. Yang X, Hu J, Zhu S, Liang X, Li J, Luo E. Computer-assisted surgical planning and simulation for condylar reconstruction in patients with osteochondroma. Br J Oral Maxillofac Surg 2011;49:203 208. 5. Wolford LM, Mehra P, Franco P. Use of conservative condylectomy for treatment of osteochondroma of the mandibular condyle. J Oral Maxillofac Surg 2002;60:262 268. 6. Cottrell DA. Discussion: use of conservative condylectomy for treatment of osterchondroma of the mandible condyle. J Oral Maxillofac Surg 2002; 60:268. 7. Iizuka T, Schroth G, Laeng RH, L adrach K. Osteochondroma of the mandibular condyle: report of a case. J Oral Maxillofac Surg 1996;54:495 501. 8. Koole R, Steenks MH, Witkamp TD, Slootweg PJ, Shaefer J. Osteochondroma of the mandibular condyle. A case report. Int J Oral Maxillofac Surg 1996;25:203 205. 9. Rivera H, Bastidas R, Acevedo AM. A conservative surgical approach of osteochondroma affecting the mandibular condyle. Invest Clin 1998;39: 117 124. 10. Kurita K, Ogi N, Echiverre NV, Yoshida K. Osteochondroma of the mandibular condyle. A case report. Int J Oral Maxillofac Surg 1999;28:380 382. 11. Aydin MA, Küçükçelebi A, Sayilkan S, Celebioğlu S. Osteochondroma of the mandibular condyle: report of 2 cases treated with conservative surgery. J Oral Maxillofac Surg 2001;59:1082 1089. 12. Vezeau PJ, Fridrich KL, Vincent SD. Literature review and report of two atypical cases. J Oral Maxillofac Surg 1995;53:954 963. 13. Kumar VV. Large osteochondroma of the mandibular condyle treated by condylectomy using a transzygomatic approach. Int J Oral Maxillofac Surg 2010;39:188 191. 14. Ortakoglu K, Akcam T, Sencimen M, Karakoc O, Ozyigit HA, Bengi O. Osteochondroma of the mandible causing severe facial asymmetry: a case 278 HEAD & NECK DOI 10.1002/HED FEBRUARY 2014
FEASIBILITY AND INDICATIONS OF THE LOCAL RESECTION report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2007;103: e21 e28. 15. Koga M, Toyofuku S, Nakamura Y, Yoshiura K, Kusukawa J, Nakamura Y. Osteochondroma in the mandibular condyle that caused facial asymmetry: a case report. Cranio 2006;24:67 70. 16. Cimino R, Steenks MH, Michelotti A, Farella M, PierFrancesco N. Mandibular condyle osteochondroma. Review of the literature and report of a misdiagnosed case. J Orofac Pain 2003;17:254 261. 17. Saito T, Utsunomiya T, Furutani M, Yamamoto H. Osteochondroma of the mandibular condyle: a case report and review of the literature. J Oral Sci 2001;43:293 297. 18. Gonzalez-Otero S, Navarro-Cuellar C, Escrig-de Teigeiro M, Fernandez- Alba-Luengo J, Navarro-Vila C. Osteochondroma of the mandibular condyle: resection and reconstruction using vertical sliding osteotomy of the mandibular ramus. Med Oral Patol Oral Cir Bucal 2009;14: E194 E197. 19. Ribas Mde O, Martins WD, de Sousa MH, Zanferrari FL, Lanzoni T. Osteochondroma of the mandibular condyle: literature review and report of a case. J Contemp Dent Pract 2007;8:52 59. 20. Holmlund AB, Gynther GW, Reinholt FP. Surgical treatment of osteochondroma of the mandibular condyle in the adult. A 5-year follow-up. Int J Oral Maxillofac Surg 2004;33:549 553. 21. Martinez-Lage JL, Gonzalez J, Pineda A, Alvarez I. Condylar reconstruction by oblique sliding vertical-ramus osteotomy. J Craniomaxillofac Surg 2004;32:155 160. 22. Gingrass DJ, Sadeghi EM. Osteochondroma of the mandibular condyle mimicking TMJ syndrome: clinical and therapeutic appraisal of a case. J Orofac Pain 1993;7:214 219. 23. Seki H, Fukuda M, Takahashi T, Iino M. Condylar osteochondroma with complete hearing loss: report of a case. J Oral Maxillofac Surg 2003;61: 131 133. 24. Peroz I, Scholman HJ, Hell B. Osteochondroma of the mandibular condyle: a case report. Int J Oral Maxillofac Surg 2002;31:455 456. HEAD & NECK DOI 10.1002/HED FEBRUARY 2014 279