A clinical study of the patients with elongated styloid process

INTRODUCTION

Styloid process is derived from the Greek word “Stylos” means a pillar, which is normally a cylindrical structure arising from the temporal bone anterior to stylomastoid foramen. The apex of the styloid process is clinically important as it is located between internal and external carotid arteries.¹ The embryonic origin of styloid process lies in the Reichert’s cartilage of the second pharyngeal arch, together with the stylohyoid ligament and the lesser horn of hyoid bone forms an apparatus called stylohyoid apparatus or stylohyoid complex.² The styloid process provides attachments to stylohyoid and stylomandibular ligaments and stylopharyngeus, stylohyoid and styloglossus muscles.³

These muscles and ligaments have a role in mastication and swallowing. This is surrounded by glossopharyngeal nerve, and carotid arteries.^4,5

The mean radiographic length of the styloid process is usually 2-3 cm and can vary from person to person and even between the same side of the same individual.⁶ When the processes exceed this average it is assigned the term elongation.²

The elongation of styloid process is considered an anomaly which can be accompanied by calcification of the stylohyoid and stylomandibular ligaments, which can trigger a series of symptoms such as dysphagia, odynophagia, facial pain, ear pain, headache, tinnitus and trismus. This set of symptoms associated with the elongated styloid process is called Eagle's syndrome.⁷

The present study was undertaken to establish a co-relation between throat and cervicofacial pain and elongated styloid process. The present study was undertaken find out the length of styloid process in patients with throat pain.

METHODS

The present observational study was conducted in the department of ENT, R I M S, Raichu from December 2015 to March 2016. Total 150 patients were enrolled with age distribution ranged from 15 years to 70 years. There were 92 females and 58 males in this study. The patients who reported with throat pain, foreign body sensation in the throat and cervico-facial pain were selected for the study. Ethical permission was obtained from the institution and informed consent was obtained from the patients. The inclusion criteria consisted of patients with throat and cervicofacial pain without other oro-pharyngeal pathology. Patients reported with throat pain with pharyngitis, tonsillitis, oro-pharyngeal ulcers and oro-pharyngeal malignancy were excluded from the study. Styloid process was assessed by palpation and by using Towne view x-ray techniques (figure 1). The results were analyzed and depicted by using bar diagrams.

RESULTS

The female to male ratio was found to be 1.6:1. Of the 150 cases 92 were middle aged females, the severity of symptoms were directly proportional to the length and the thickness of the styloid. The symptoms ranged from foreign body sensation in the throat to cervico facial pain and otalgia. Serum Calcium levels were elevated in 60% of the cases.

Table 1 is shows the length of right sided styloid process in which length of the styloid process ranged between 2.5 cm to 3.5 in 43 females and 17 males, ranged between 3.6- 4.5 cm in 47 females and 25 males, between 4.6-5.5 cm length in 4 females and 12 males and in none of the female ranged more than 5.5 cm but 2 male patients revealed 5.6-6.5 cm of length styloid process at right side (Figure 2). Table 2 is shows the length of left sided styloid process in which 44 female and 19 male have range between 2.5 cm to 3.5, in 45 female and 26 male patients, it ranged between 3.6- 4.5 cm, in 4 female and 11 male it ranged between 4.6-5.5 cm length and none of female ranged more than 5.5 cm but 1 male have 5.6-6.5 cm of length styloid process at left side (Figure 3).

DISCUSSION

The styloid process is a bony projection, situated immediately anterior to the stylomastoid foramen, averaging from 2 to 2.5 cm in length. It is of cylindrical form and projects downwards from the inferior surface of the temporal bone towards the front, downwards and medially narrowing towards the tip. The location of the tip is particularly is important, which is situated between the internal and external carotid arteries, laterally from the pharyngeal wall and immediately behind the tonsil fossa.⁸

Patients most often complain of pain in the pharynx, a sensation of the presence of a foreign object (fish bone), pain on swallowing which radiates to the area of the ear on the same side. Clinically, hardness can occasionally be felt in the tonsillar fossa which is painful on palpation.⁹ It is supposed that this symptoms and signs are due to the compression of the SP on some neural and vascular structures. More uncommonly, symptoms such as dysphagia, tinnitus, and otalgia may occur in patients with this syndrome.¹⁰ Diagnosis is made both radiographically and by physical examination. Palpation of the styloid process in the tonsillar fossa is indicative of elongated styloid in that processes of normal length are not normally palpable. Palpation of the tip of the styloid should exacerbate existing symptoms.¹¹ If the styloid process causes pressure on the area of the carotid arteries, the symptoms are more complicated. Pain may occur in the areas that supply the internal and external carotid arteries. In the case of affection of the external carotid, the case history records buzzing in the ears, pain during movement of the head and pain in the anterior neck triangle. Symptoms with regard to the internal carotid may be headache in the area of the orbit and other areas that supply that artery. Although the elongated styloid process is usually bilateral, the symptoms and disturbances are most frequently unilateral.⁹

Clinically, the syndrome is most commonly seen after the age of 30 years. There is no significant sex predilection in occurrence of mineralization of the styloid process, however, symptoms are more common in females.¹² In the present study, the female to male ratio was found to be 1.6:1. Of the 150 cases 92 were middle aged females, the severity of symptoms were directly proportional to the length and the thickness of the styloid. The symptoms ranged from foreign body sensation in the throat to cervico facial pain and otalgia.

The patients with the length between 2.5 cm to 3.5 cm complained of the foreign body sensation in the throat. The patients with the length between 3.6 cm to 4.5 cm complained of throat pain, pain in the ear, and pain in the throat on changing the position of the head, pain aggravated on swallowing. The patients with the length between 4.6 cm to 6.5 cm complained of throat pain, pain in the ear, and pain in the throat on changing the position of the head, pain aggravated on swallowing and cervico-facial pain mimicking glossopharyngeal neuralgia secondary to impingement of the glossopharyngeal nerve. The elongated styloid process showed a female preponderance with 61% cases reported among females. This was comparable with the study conducted by Bafaqeeh S A.¹³ Some of the studies have shown the entrapment the chorda tympani, trigeminal and the glossopharyngeal nerves, but our study did not reveal about the involvement of the chorda tympani.¹⁴ It has been suspected that an elongated styloid process could be caused by congenital elongation of the styloid process due to persistence of the cartilaginous analogue of the Styloid, calcification of the stylohyoid ligament by unknown mechanism and growth of osseous tissue at the insertion of the stylohyoid ligament.¹⁵ 60% of our cases show a raised calcium levels.

Rathva et al determined the mean length of the styloid process on 150 dry skulls to investigate the incidence of the elongated styloid process and the relations of the styloid processes to other structures at the base of the skull and found elongated styloid process in upto 2% of dry skull.¹⁶

The prevalence of styloid process elongation or stylohyoid ligament mineralization in imaging studies has been reported to be between 19.4% to 52.1% in the general population5 and in up to 76% of patients with temporomandibular disorder8. However, the incidence of Eagle syndrome in the general population is underestimated since only 6% of those with an elongated styloid process have symptoms.¹⁷

CONCLUSIONS

Elongated styloid process can be a source of craniofacial and cervical pain and remains a diagnostic challenge to many.¹⁸ The diagnosis could be established by detailed history taking, palpation of the styloid and radiological (Towne) view The presence of the elongated styloid process and its angulation, though rare, does highlight the importance of routine examination of the styloid process even in clinical practice.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: The study was approved by the Institutional Ethics Committee

REFERENCES

1. 1. Shaik MA, Naheeda, Kaleem SM, Wahab A, Hameed S. Prevalence of elongated styloid process in Saudi population of Aseer region. European Journal of Dentistry. 2013;7(4):449-54.
2. 2. Kadiyala SV, Kumar S. Anatomical Variations in the Length of Styloid Process. Int J Pharm Sci Rev Res 2015;33(2):123-5.
3. 3. Standring Susan (Ed). Gray’s Anatomy. The anatomical basis of clinical practice. Edinburgh; Elsevier Churchill Livingstone. 2000: 450-470,
4. 4. Cawich S, Gardner M, Johnson P, Shetty R, Wolf K. The clinical significance of an elongated styloid process. The Internet Journal of Family Practice. 2007;6(1):1-5.
5. 5. Ghosh LM, Dubey SP. The syndrome of elongated styloid process. Auris Nasus Larynx. 1999;26(2):169-75.
6. 6. Bozkir MG, Boga H, Dere F. The evaluation of styloid process in panoramic radiographs in edentulous patients. Turk J Med Sci. 1999;29:481–5.
7. 7. Lins CCSA, Junior AA, Oliveira BP, Silva EMVM, Torres RCMS. Variation of length of styloid process. Int J Morphol. 2010;28(4):1277-1280.
8. 8. Teki S, Latha A, Babu S, Kumari L, Prasad GS, Vasanthi A. Eagle’s Syndrome- Elongated Styloid Process. IOSR J Dental Med Sci. 2014;13(5):31-3.
9. 9. Sandev S, Sokler K. Styloid Process Syndrome. Acta Stomat Croat. 2000;34(4):451-6.
10. 10. Gokce C, Sisman Y, Sipahioglu M. Styloid Process Elongation or Eagle’s Syndrome: Is There Any Role for Ectopic Calcification? Eur J Dent. 2008;2:224-8.
11. 11. Rechtweg JS, Wax MK. Eagle's syndrome: a review. Am J Otolaryngol. 1998;19:316-21.
12. 12. Feldman VB. Eagle's syndrome: a case of symptomatic calcification of the stylohyoid ligaments. J Can Chiropr Assoc. 2003;47(1):21-7.
13. 13. Bafaqeeh S A, Eagle syndrome; classic and carotid artery types. JORL. 2000;29:88-94.
14. 14. Harma R. Stylalgia clinical experience of 52 cases. Acta otolaryngol. 1966;224:149-55.
15. 15. Murtagh R, Caracciolo J and Fernandez G: CT Findings associated with Eagle syndrome. AJNR. 2001,22:1401-2.
16. 16. Angulation and Distance between the Two Styloid Processes. International Journal of Recent Trends in Science And Technology. 2013;8(2):109-12.
17. 17. Taheri A, Firouzi-Marani S, Khoshbin M. Nonsurgical treatment of stylohyoid (Eagle) syndrome: a case report. J Korean Asso Oral Maxillofacial Surg. 2014;40(5):246-9.
18. 18. Prasad KC, Kamath MP, Reddy KJ, et al. Elongated styloid process (Eagle's syndrome): a clinical study. J Oral Maxillofac Surg. 2002;60(2):171-5.