Myositis Ossificans Traumatica of the Medial Pterygoid Muscle After Third Molar Tooth Extraction: A Case Report and Review of Literature

DENTOALVEOLAR SURGERY

Myositis Ossificans Traumatica of the Medial Pterygoid Muscle After Third Molar Tooth Extraction: A Case Report and Review of Literature Soner Karaali, MD,* and Ufuk Emekli, MDy Myositis ossificans (MO) is a rare non-neoplastic disorder characterized by heterotopic ossification in soft tissues, mainly muscles. MO traumatica is characterized by ossification of the soft tissues after acute or repetitive trauma, burns, or surgical intervention. Muscular or soft tissue trauma is usually present as the underlying etiology. MO traumatica usually involves the extremity muscles. The number of reported cases involving the masticatory muscles is extremely low. The most common clinical sign of this condition is progressive limitation of mouth opening. Surgical resection of the ossified tissue has been the most commonly used treatment for this disorder, with a high postoperative recurrence rate. We report a case of traumatic MO of the medial pterygoid muscle to draw attention to the possibility of the condition in patients with a limited mouth opening and to review the reported data about MO traumatica involving the medial pterygoid muscle. Ó 2018 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg -:1.e1-1.e5, 2018 Myositis ossificans (MO) is a rare disorder characterized by heterotopic ossification in muscle or soft tissue. MO can be divided into 2 disease groups with different etiologies and pathophysiologies, namely MO progressiva (MOP) and MO traumatica (MOT).1 MOP (or fibrodysplasia ossificans progressiva) is a genetic disorder inherited in an autosomal dominant pattern. It is characterized by simultaneously occurring multiple heterotopic ossifications involving the muscles, tendons, fascia, ligaments, and other soft tissues.2-6 However, MOT (or MO circumscripta) is an acquired disorder characterized by heterotopic calcification of the muscles and other soft tissues after acute or chronic trauma, burns, or surgical intervention.1,3,4 MOT is a rare disorder that most commonly involves the extremities after trauma. Involvement of

masticatory muscles is a much rarer occurrence, with the masseter muscle the most commonly involved.7 In the reported data, 16 cases of MO involving the medial pterygoid muscle have been reported.1,2,5-18 Isolated medial pterygoid muscle involvement or multiple masticatory muscle involvement can both occur in these patients. To date, 6 cases of MO involving the medial pterygoid muscle after tooth extraction have been reported.2,5,8,14,15,18 To diagnose MOT, the patient’s trauma history should be thoroughly investigated. After history and physical examination, radiologic and/or microscopic findings will be sufficient for making the diagnosis. Progressive limitation of mouth opening is the most common clinical sign.2-4

Received from Department of Plastic Reconstructive and Aesthetic Surgery, Maxillofacial Surgery, Istanbul University, Istanbul Faculty

Maxillofacial Surgery, Istanbul University, Istanbul Faculty of € Medicine, Topkapı Mahallesi, Turgut Ozal Caddesi No. 118, Fatih,

of Medicine, Turkey. *Physician.

34093 Istanbul; e-mail: [email protected] Received February 25 2018

yProfessor.

Accepted June 28 2018

Conflict of Interest Disclosures: None of the authors have any

Ó 2018 American Association of Oral and Maxillofacial Surgeons

relevant financial relationship(s) with a commercial interest.

0278-2391/18/30759-6

Address correspondence and reprint requests to Dr Karaali:

https://doi.org/10.1016/j.joms.2018.06.174

Department of Plastic Reconstructive and Aesthetic Surgery,

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MO TRAUMATICA OF MEDIAL PTERYGOID MUSCLE

We report a case of MO traumatica involving the medial pterygoid muscle after molar tooth extraction. We also provide a review of the relevant reported data on MOT of the medial pterygoid muscle. Our report was exempt from institutional review board approval because it was a case report. We followed the Declaration of Helsinki guidelines, and the patient provided written informed consent for publication of the clinical photographs.

Case Report A 30-year-old woman presented to our clinic with limited mouth opening. She had undergone right lower third molar tooth extraction in September 2016 because of the abnormal position of the tooth. The extraction was completed without difficulty. She had experienced progressive limitation of mouth opening after the procedure, and she had been treated by her dentist with nonsteroidal anti-inflammatory drugs and empirical antibiotics for surgical site infection for 1 week. However, the limitation of mouth opening continued progressively, and the patient neglected her follow-up appointments. Because of the persistence of the limited mouth opening, she presented to a Faculty of Dentistry, which referred her to our clinic, the Istanbul University Istanbul Faculty of Medicine, Department of Plastic Reconstructive and Aesthetic Surgery, Maxillofacial Surgery Unit in August 2017. On her admission physical examination, she had a mouth opening of 0 mm. She had a ‘‘lateral open bite’’ deformity that she stated she had had previously, and a leftward shift of her mandible’s midline. On palpation, she had no intraoral or neck lymphadenopathy or mass. Her blood tests revealed a normal complete blood count, serum calcium, phosphate, parathyroid and calcitonin hormones, and urinary calcium level. A 3-plane thin-slice maxillofacial computed tomography (CT) scan showed a lesion, consistent with an irregular heterotopic calcification, at the line passing from the inner side of the right mandibular ramus toward the pterygoid process, corresponding to the anatomic site of the right medial pterygoid muscle (Fig 1). The CT scan showed no additional pathologic features. Magnetic resonance imaging of the bilateral temporomandibular joints (TMJ) showed no TMJ pathology. From the physical examination and imaging test findings, MOT involving the right medial pterygoid muscle was diagnosed. Because her mouth opening was 0 mm, the patient was offered surgical resection of the calcific foci using an extraoral approach. However, she refused surgery owing to the potential risks and the possibility of postoperative recurrence. Therefore, a course of physical therapy was begun. She was treated with daily intense passive stretching exercises. Her maximal incisal opening had

FIGURE 1. (A) Axial computed tomography (CT) scan confirming the presence of irregular heterotrophic calcification involving the right medial pterygoid muscle. (B) Coronal CT scan confirming the presence of irregular heterotrophic calcification involving the right medial pterygoid muscle. Karaali and Emekli. MO Traumatica of Medial Pterygoid Muscle. J Oral Maxillofac Surg 2018.

reached 5 mm at the second month and 14 mm at the fifth month. With the increase in the mouth opening, active stretching exercises were added to the passive stretching exercises. At the last follow-up examination, the patient was continuing to receive intensive physical therapy and attend follow-up visits at our clinic.

Discussion A search of the reported medical data in the English language revealed 17 cases of MOT involving the medial pterygoid muscle, including our report (Table 1).1,2,5-18 Although isolated medial pterygoid muscle involvement was observed in 11 of these cases,6-8,11,13,14,17,18 the other 6 cases had combined involvement of the medial pterygoid muscle and other masticatory muscles.1,2,5,12,15,17

Pt. No.

Investigator

Year

Age (yr)

Sex

Location

1 2 3

Narang et al8 Nilner et al9 Parkash and Goyal10

1974 1989 1992

49 57 28

M M M

Medial pterygoid Medial pterygoid Medial pterygoid

Tooth extraction Anesthetic injection Pericoronitis

4 5

Tong et al11 Spinazze et al12

1994 1998

73 55

F M

Bilateral medial pterygoid Masseter, temporal, lateral pterygoid, medial pterygoid

Anesthetic injection Periodontal surgery

Excision Physical therapy Excision, condylectomy, coronoidectomy Biopsy Coronoidectomy

6 7

Takahashi and Sato7 Aoki et al1

1999 2002

71 44

F M

Unknown Struck on cheek

Excision Excision

8

Rattan et al6

2008

45

M

Medial pterygoid Masseter, lateral pterygoid, medial pterygoid Medial pterygoid

Unknown Twice, followed by excision, arthroplasty plus osteotomy None Yes

Excision

None

9

Conner et al2

2009

18

F

Medial pterygoid, temporal

Alcohol injection for trigeminal neuralgia Surgical extraction of third molars

Excision and coronoidectomy

10

Ramieri et al5

2010

64

M

Tooth extraction

11

Trautmann et al13

2010

33

M

Lateral pterygoid, temporal; then medial pterygoid Medial pterygoid

High condylectomy, then excision Excision

Twice, followed by mandibular resection and condylar disarticulation Unknown

12

Thangavelu et al14

2011

36

F

Medial pterygoid

13

Ebbert et al15

2012

45

M

14

Boffano et al16

2014

37

F

Bilateral medial and lateral pterygoid Medial pterygoid

15

Reddy et al17

2014

21

M

16 17

Torres et al18 Present case

2015 2018

36 30

F F

Medial pterygoid and temporal Medial pterygoid Medial pterygoid

History of Trauma

Anesthetic injection, coronoidectomy Tooth extraction Tooth extraction Blow to face Blow to face Tooth extraction Tooth extraction

Treatment

Excision and interpositional fat graft Surgery deferred Excision, condylectomy, coronoidectomy Excision and coronoidectomy Excision Physical therapy

Recurrence Within 1 month Unknown None

KARAALI AND EMEKLI

Table 1. CASE REPORTS OF MYOSITIS OSSIFICANS TRAUMATICA INVOLVING THE MEDIAL PTERYGOID MUSCLE

Unknown None Unknown None None Yes None

Abbreviations: F, female; M, male; Pt. No., patient number. Karaali and Emekli. MO Traumatica of Medial Pterygoid Muscle. J Oral Maxillofac Surg 2018.

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1.e4 The etiology of the reported MOT cases included tooth extraction, odontogenic infections, anesthetic injections, and external trauma.19 Six cases of MOT involving the medial pterygoid muscle after tooth extraction have been reported to date.2,5,8,14,15,18 In the reported data, the patients with medial pterygoid muscle MOT had a mean age of 43.6 years and a male/female ratio of 1.42:1. Many theories have been put forth to explain the pathogenesis of MOT; however, the mechanism is not yet fully understood.20 Carey21 presented the following hypotheses: malalignment of the bony fragments in the soft tissue and their subsequent proliferation; dispatch of periosteal fragments from bone to adjacent soft tissue and osteoprogenitor cell proliferation; migration of subperiosteal osteoprogenitor cells into surrounding soft tissue resulting from posttraumatic periost perforation; and ossification in the soft tissue after metaplasia in extraosseous tissues by the effect of bone morphogenic proteins released by bone fragment lysis after trauma.21 A theory for the development of MOT commonly referenced by multiple scientific reports involves overaccumulation of vascular granulation tissue after bleeding and its subsequent metaplasia to cartilaginous bone.14,22,23 MOT is a rare disorder of the maxillofacial region, and the masseter muscle is the most commonly

MO TRAUMATICA OF MEDIAL PTERYGOID MUSCLE

involved muscle.7 This could be because the masseter muscle covers a large portion of the outer surface of the mandible and thus is the most exposed to trauma.22 Our patient had not experienced external trauma episode. Instead, the medial pterygoid muscle located on the inner surface of the mandible had been affected by an intraoral surgical procedure. MOT of the maxillofacial region mostly manifests itself with limited mouth opening.2-4 However, the disorder can be asymptomatic in its early stages. Its differential diagnosis should include mandibular fractures, TMJ disorders (eg, ankylosis, disc disorders), and mandibular masses and infections, which can produce similar symptoms. Therefore, radiologic imaging is very important for the diagnosis, and the use of CT is crucial for diagnosis and treatment planning. According to Boffano et al,16 an ossified mass characterized by a zonal pattern, clear lesion borders, and radiopacity that increases from the center to the periphery is pathognomonic.16 Our patient’s lesion also showed increased radiolucency toward the center of the calcified mass on the CT images (Fig 2). The reported data suggest operative and nonoperative treatment options for MOT.14 Surgical resection has been the most commonly used treatment. The surgical options include resection of the calcified mass, coronoidectomy and/or condylectomy,

FIGURE 2. Pathognomonic zonal pattern with increased radiolucency toward the center of the calcified mass on computed tomography images (red arrow) and radiopacity increasing from the center to the periphery (green arrow). Karaali and Emekli. MO Traumatica of Medial Pterygoid Muscle. J Oral Maxillofac Surg 2018.

KARAALI AND EMEKLI

and interpositional fat graft applications after mass resection.9,11,24,25 The nonoperative options include physical therapy, medical therapy (eg, nonsteroidal anti-inflammatory drugs, bisphosphonates, magnesium), and low-dose radiotherapy.14 However, postresection recurrence has been frequently reported, possibly because surgical treatment can create additional trauma, an important cause of this disorder. In our case, tooth extraction was the etiology. As stated, a variety of treatment options are available for MOT, and no standard treatment protocol is available, because the disorder is rare and only reported in case reports.2 We recommended to our patient to undergo surgery, the most widely recognized treatment modality worldwide. However, she refused surgery, which led us to begin an aggressive physical therapy program, which eventually increased her mouth opening. The 14-mm increase of mouth opening provided by physical therapy was preserved at 6 months of follow-up. The patient has continued physical therapy under our care, and we might consider surgical treatment if the increase in mouth opening achieved by physical therapy cannot be maintained in the long-term. In conclusion, MOT is a rare disorder involving the maxillofacial region, presenting most commonly with limitation of mouth opening. Surgical resection has been the most widely used and recommended treatment modality, although recurrences have been common with this approach. Our patient was also recommended to undergo surgery, the most commonly recommended treatment option in the reported data. Because she refused surgery, however, an aggressive physical therapy program was begun, which was noted to improve her mouth opening. Surgical treatment has not been excluded for our patient, and physical therapy was not considered as an alternative therapy to surgery. Surgery can still be considered if the patient’s mouth opening becomes limited despite treatment. However, physical therapy can benefit these patients and can also be used as an ancillary treatment modality. Because we found no ideal treatment protocol in the reported data, further research on this subject is warranted.

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1.e5 2. Conner GA, Duffy M: Myositis ossificans: A case report of multiple recurrences following third molar extractions and review of the literature. J Oral Maxillofac Surg 67:920, 2009 3. Godhi SS, Singh A, Kukreja P, Singh V: Myositis ossificans circumscripta involving bilateral masticatory muscles. J Craniofac Surg 22:e11, 2011 4. Kim DD, Lazow SK, Har-El G, Berger JR: Myositis ossificans traumatica of masticatory musculature: A case report and literature review. J Oral Maxillofac Surg 60:1072, 2002 5. Ramieri V, Bianca C, Arangio P, Cascone P: Myositis ossificans of the medial pterygoid muscle. J Craniofac Surg 21:1202, 2010 6. Rattan V, Rai S, Vaiphei K: Use of buccal pad of fat to prevent heterotopic bone formation after excision of myositis ossificans of medial pterygoid muscle. J Oral Maxillofac Surg 66:1518, 2008 7. Takahashi K, Sato K: Myositis ossificans traumatica of the medial pterygoid muscle. J Oral Maxillofac Surg 57:451, 1999 8. Narang R, Dixon RA Jr: Myositis ossificans: Medial pterygoid muscle—A case report. Br J Oral Surg 12:229, 1974 9. Nilner M, Petersson A: Mandibular limitation due to enlarged pterygoid process and calcification of the medial pterygoid muscle: A case report. Cranio 7:230, 1989 10. Parkash H, Goyal M: Myositis ossificans of medial pterygoid muscle: A cause for temporomandibular joint ankylosis. Oral Surg Oral Med Oral Pathol 73:27, 1992 11. Tong KA, Christiansen EL, Heisler W, et al: Asymptomatic myositis ossificans of the medial pterygoid muscles: A case report. J Orofac Pain 8:223, 1994 12. Spinazze RP, Heffez LB, Bays RA: Chronic, progressive limitation of mouth opening. J Oral Maxillofac Surg 56:1178, 1998 13. Trautmann F, Moura PD, Fernandes TL, et al: Myositis ossificans traumatica of the medial pterygoid muscle: A case report. J Oral Sci 52:485, 2010 14. Thangavelu A, Vaidhyanathan A, Narendar R: Myositis ossificans traumatica of the medial pterygoid. Int J Oral Maxillofac Surg 40: 545, 2011 15. Ebbert TL, Baima JJ Jr, Smoker WR: Radiology quiz case 1: Myositis ossificans of the bilateral medial and lateral pterygoid muscles. Arch Otolaryngol Head Neck Surg 138:422, 2012 16. Boffano P, Zavattero E, Bosco G, Berrone S: Myositis ossificans of the left medial pterygoid muscle: Case report and review of the literature of myositis ossificans of masticatory muscles. Cranimaxillofac Trauma Reconstr 7:43, 2014 17. Reddy SP, Prakash AP, Keerthi M, Rao BJ: Myositis ossificans traumatica of temporalis and medial pterygoid muscle. J Oral Maxillofac Pathol 18:271, 2014 18. Torres AM, Nardis AC, da Silva RA, Savioli C: Myositis ossificans traumatica of the medial pterygoid muscle following a third molar extraction. Int J Oral Maxillofac Surg 44:488, 2015 19. Ungari C, Filiaci F, Riccardi E, et al: Etiology and incidence of zygomatic fracture: A retrospective study related to a series of 642 patients. Eur Rev Med Pharmacol Sci 16:1559, 2012 20. Mevio E, Rizzi L, Bernasconi G: Myositis ossificans traumatica of the temporal muscle: A case report. Auris Nasus Larynx 28:345, 2001 21. Carey EJ: Multiple bilateral parosteal bone and callus formations of the femur and left innominate bone. Arch Surg 8:592, 1924 22. Abdin HA, Prabhu SR: Traumatic myositis ossificans of lateral pterygoid muscle. J Oral Med 39:54, 1984 23. Ungari C, Quarato D, Gennaro P, et al: A retrospective analysis of the headache associated with temporomandibular joint disorder. Eur Rev Med Pharmacol Sci 16:1878, 2012 24. Nizel AE, Prigge EK: Trismus due tomyositis ossificans traumatica: Report of a case. J Oral Surg (Chic) 4:93, 1946 25. Hellinger MJ: Myositis ossificans of the muscles of mastication. Oral Surg Oral Med Oral Pathol 19:581, 1965