Tinnitus (ringing or buzzing in the ears) affects approximately 10-15% of the adult population and significantly reduces quality of life in many patients. In a substantial proportion of cases, tinnitus is associated with dysfunction of the temporomandibular joint (TMJ) and cervical spine - this subtype is called somatosensory tinnitus.

This randomised controlled trial investigates the effectiveness of a multimodal intervention combining: (1) physiotherapy targeting TMJ and cervical spine dysfunction, (2) a structured combined exercise program (aerobic + resistance + breathing), and (3) psychological support (cognitive-behavioural psychoeducation) in patients with chronic somatosensory tinnitus.

The study also examines the acute effects of different types and intensities of physical exercise on tinnitus perception, and performs psychometric validation of Czech-language tinnitus assessment questionnaires.

Participants (N=160, aged 18-70 years) will be randomly assigned to either the multimodal intervention group (8 weeks, 5 sessions/week) or a control group. Follow-up assessments will be conducted at 3, 12, and 24 months. The primary outcome is the change in the Tinnitus Handicap Inventory (THI) score.

Background: Somatosensory tinnitus represents a clinically significant subgroup in which tinnitus is modulated by somatic manoeuvres (jaw movements, cervical rotation, trigger point palpation). The neuroanatomical basis involves convergence of somatosensory afferents from the TMJ and upper cervical spine (C1-C3) in the medullary nucleus spinalis nervi trigemini, with excitatory projections to the dorsal cochlear nucleus (DCN), leading to disinhibition of spontaneous neural activity perceived as tinnitus (Da Silva et al., 2023). Despite this evidence, multimodal treatment protocols specifically targeting somatosensory tinnitus remain largely absent from clinical practice in the Czech Republic.

Study Design: Single-centre randomized controlled trial with longitudinal follow-up and a crossover substudy on acute exercise effects. Stratified randomization by age group (18-35 / 36-50 / 51-70 years) and sex. Rotating block system: 4 blocks of ~27 participants; 8 weeks active intervention + 8 weeks pause per block.

Intervention: 8-week multimodal program comprising: (A) Physiotherapy - 16 sessions × 60 min: manual therapy of TMJ and cervical spine (myofascial techniques including intraoral TMJ techniques), neuromuscular exercise, proprioceptive training, home exercise program; (B) Exercise Program - 24 sessions × 60 min: combined aerobic (60-85% HRmax), resistance (40-80% 1RM), and breathing/relaxation training; 1× supervised/week + 2× home-based/week; (C) Psychological Support - 1× group psychoeducation session (90 min): cognitive-behavioral model of tinnitus distress, attention regulation, relaxation; weekly self-help materials; on-demand psychological support (max. 3× per 8 weeks).

Crossover Substudy: Repeated measures crossover design examining acute effects of 5 standardized conditions (low/high intensity aerobic exercise; low/high intensity resistance exercise; control rest) on tinnitus perception (VAS loudness and distress), with ≥48-72h washout between conditions.

Questionnaire Validation: Psychometric validation of Czech versions of THI, TFI, TCS, MTQ, CRF, TSCHQ, MDI, and WB questionnaires according to COSMIN guidelines, including reliability, validity, responsiveness, and MID determination.

Outcomes: Primary: THI change from baseline to 3, 12, and 24 months. Secondary: TFI, VAS/NRS, CGI, GAD-7, PHQ-9, PSQI, SF-36, WHO-5, cervical ROM, TMJ function (JFLS-20), NDI, CPET parameters (VO₂peak), body composition (BIA), muscle strength, autonomic regulation (BP, HR, PWV), and EEG spectral analysis (exploratory).

Inclusion Criteria:

• Age 18-70 years (inclusive)
• Chronic subjective tinnitus present for ≥6 months
• Tinnitus Handicap Inventory (THI) score ≥18 points (indicating at least mild tinnitus handicap)
• Positive somatosensory modulation test: ability to reproducibly modulate tinnitus (change in loudness, pitch, or quality) through at least one of the following manoeuvres:
• Jaw movements (mouth opening, lateral excursion, protrusion, clenching)
• Neck movements (flexion, extension, rotation, lateral flexion)
• Pressure on specific head/neck muscles
• Eye movements or shoulder elevation
• Willing and able to attend all study sessions over 28 weeks
• Adequate cognitive capacity to understand study procedures and complete questionnaires in the Czech language
• Signed written informed consent

Exclusion Criteria:

• Audiological/ENT Exclusions:
• Objective or pulsatile tinnitus
• Active ear pathology requiring treatment:
• Acute otitis media or externa
• Chronic suppurative otitis media
• Cholesteatoma
• Meniere's disease with recent vertigo attacks (<3 months)
• Suspected retrocochlear pathology:
• Acoustic neuroma (vestibular schwannoma)
• Cerebellopontine angle tumor
• Neurological Exclusions:
• Neurological disease affecting brainstem or auditory pathways:
• Multiple sclerosis with brainstem involvement
• Stroke affecting auditory pathways
• Brain tumor
• Epilepsy or active seizure disorder
• Musculoskeletal Exclusions:
• Contraindications to manual therapy:
• Severe cervical spine instability
• Rheumatoid arthritis with atlantoaxial instability
• Down syndrome
• Vertebrobasilar insufficiency
• Severe osteoporosis with fracture risk
• Recent cervical spine surgery (<6 months)
• Recent head or neck trauma (<3 months)
• Ongoing physiotherapy or manual therapy for temporomandibular joint or cervical spine (<3 months prior to enrollment)
• Psychiatric Exclusions:
• Severe psychiatric disorder:
• Active psychosis
• Severe depression requiring inpatient treatment
• Acute suicidal ideation (PHQ-9 item 9 score ≥2)
• Active substance abuse disorder
• Other Exclusions:
• Pregnancy (due to modifications needed in physical examination and treatment)
• Ongoing litigation or compensation claims related to tinnitus or hearing loss
• Current participation in another interventional clinical trial
• Expected change of residence or long-term absence (>2 weeks) during the study period
• Unable or unwilling to comply with study procedures and attend all sessions