Somatic Modulation in Tinnitus: Clinical Characteristics and Treatment Outcomes

The Association Between Temporomandibular Disorders and Tinnitus: Evidence and Therapeutic Perspectives from a Systematic Review

Background/Objectives: Tinnitus, often described as a ringing in the ears, affects a significant portion of the population, varying in perception and severity. Methods: This systematic review investigates the correlation between tinnitus and temporomandibular joint disorders (TMDs) within a PRISMA-compliant framework, ensuring methodological transparency and rigor. Using databases, such as PubMed, Scopus, and Web of Science, we analyzed studies from the past decade to evaluate clinical and observational evidence. Results: A significant association between TMD and tinnitus was found, with somatosensory and neuroplastic mechanisms contributing to this relationship. Key therapeutic approaches identified include manual therapy and multidisciplinary treatments, demonstrating potential clinical efficacy. Conclusions: However, the available evidence remains inconsistent, emphasizing the need for further research with standardized methodologies to improve understanding and refine therapeutic strategies. This review provides a foundation for future studies aiming to enhance tinnitus management by addressing underlying TMD-related mechanisms.

Pilot study on the role of somatic modulation in hyperacusis

BACKGROUND

Hyperacusis is a reduced tolerance to sounds that often co-occurs with tinnitus. Both symptoms have convergent as well as divergent characteristics. Somatic modulation, changes in pitch or loudness during certain movements, is common in patients with a primary complaint of tinnitus. However, thus far, this is not documented in patients with hyperacusis.

OBJECTIVES

This study aimed to examine the influence of somatic manoeuvres on the perception of external sounds in patients with a primary complaint of hyperacusis.

METHODOLOGY

In this prospective cross-sectional pilot study, 18 patients with a primary complaint of hyperacusis were recruited at the Tinnitus Treatment and Research Center Antwerp (TINTRA). While patients listened to a 1 kHz broadband noise of 30 dB sensation level, six neck manoeuvres (flexion, extension, lateroflexion left/right, traction and compression), three jaw manoeuvres (protrusion, laterotrusion left/right) and one placebo manoeuvre (hand on head) were performed. The primary outcome measure was the change in the perception of the presented sound in terms of loudness and intrusiveness between baseline and each modulation measured by a visual analogue scale (VAS).

RESULTS

No overall significant changes were found; however, individual results indicated that five patients presented a clinically relevant change of more than three points out of ten on VAS in terms of hyperacusis after at least one of the executed somatic manoeuvres.

CONCLUSIONS

This pilot study did not demonstrate an overall significant change in hyperacusis after somatic manoeuvres but does not rule out the possibility of somatic modulation in some hyperacusis patients.

TRIAL REGISTRATION

The protocol of this prospective cross-sectional pilot study was registered on clinicaltrials.gov with registration number NCT04693819.

Audiological and psychological assessment of tinnitus patients with normal hearing

Introduction

This study was performed to assess identifiable abnormalities in tinnitus patients with normal hearing.

Methods

The medical records of subjective non-pulsatile tinnitus patients with normal hearing confirmed by conventional pure-tone audiometry who visited our tinnitus clinic between March 2020 and May 2022 were reviewed. The loudness discomfort level (LDL), extended high-frequency hearing loss (EHFHL), summating potential (SP)/action potential (AP) ratio, distortion product otoacoustic emission (DPOAE), thresholds of auditory brainstem response (ABR) wave V, somatic modulation, and psychiatric symptoms, such as anxiety, depression, and stress were evaluated by questionnaires.

Results

Decreased LDL (n = 48, 59.8%) was the most frequent finding, followed by EHFHL (n = 29, 35.4%), increased SP/AP ratio (n = 27, 32.9%), psychiatric symptoms (n = 24, 29.3%), decreased DPOAE (n = 17, 20.7%), somatic modulation (n = 8, 9.8%), and increased ABR threshold (n = 3, 3.7%); 75.6% of patients had one or more of these findings. The presence of psychiatric symptoms was independently associated with the Tinnitus Handicap Inventory (THI) score.

Conclusion

Tinnitus in patients with normal hearing may be accompanied by a combination of various subclinical abnormal audiological findings. However, the presence of psychiatric symptoms alone was independently associated with tinnitus distress.

Methods, Applications, and Limitations of Somatic Maneuvers for the Modulation of Tinnitus

The modulation of tinnitus through somatic maneuvers is a well-documented phenomenon in tinnitus patients with somatic disorders. The purpose of this study was to review the methods, applications, and limitations of somatic maneuvers. First, 35 somatic maneuvers proposed by various research groups were summarized according to four body areas (jaw, head and neck, eye, and limbs), following which their applications and limitations were assessed. Although some studies have shown that somatic maneuvers can aid in screening for somatic tinnitus and may help alleviate symptoms with repeated practice, the limited number of studies and inconsistent results among studies make it difficult to draw definitive conclusions. Therefore, follow-up studies are required to overcome these limitations and determine whether the treatment of somatic disorders can also aid in alleviating somatic tinnitus.