Clinical Reasoning for the Examination and Physical Therapy Treatment of Temporomandibular Disorders (TMD): A Narrative Literature Review

Abstract

The current narrative literature review aims to discuss clinical reasoning based on nociceptive pain mechanisms for determining the most appropriate assessment and therapeutic strategy and to identify/map the most updated scientific evidence in relation to physical therapy interventions for patients with temporomandibular disorders (TMDs). We will also propose an algorithm for clinical examination and treatment decisions and a pain model integrating current knowledge of pain neuroscience. The clinical examination of patients with TMDs should be based on nociceptive mechanisms and include the potential identification of the dominant, central, or peripheral sensitization driver. Additionally, the musculoskeletal drivers of these sensitization processes should be assessed with the aim of reproducing symptoms. Therapeutic strategies applied for managing TMDs can be grouped into tissue-based impairment treatments (bottom-up interventions) and strategies targeting the central nervous system (top-down interventions). Bottom-up strategies include joint-, soft tissue-, and nerve-targeting interventions, as well as needling therapies, whereas top-down strategies include exercises, grade motor imagery, and also pain neuroscience education. Evidence shows that the effectiveness of these interventions depends on the clinical reasoning applied, since not all strategies are equally effective for the different TMD subgroups. In fact, the presence or absence of a central sensitization driver could lead to different treatment outcomes. It seems that multimodal approaches are more effective and should be applied in patients with TMDs. The current paper also proposes a clinical decision algorithm integrating clinical diagnosis with nociceptive mechanisms for the application of the most appropriate treatment approach.

Keywords: exercise; grade motor imagery; manual therapy; needle; neurodynamics; pain neuroscience education; soft tissue; temporomandibular disorders.

Figure 1

Accessory movement in the transverse sliding of the TMJ (temporomandibular joint) towards lateral (A) and with an angulation towards 30° posterior (B). Movement diagram A shows exponential curve (R1-R2) with no limitation when the average movement excursion is 2 mm. The reproduction of ear pain is minimal (P1-P”) (2/10 on a numerical pain rate scale, NPRS). Movement diagram B shows the angulated transverse to lateral, where R1-R2 is more than 50% restricted and the ear pain is stronger (6/10 NPRS), suggestive of lateral pterygoid muscle involvement. Reprinted with permission from Physikalisch Untersuchung von Dysfunktionen der kraniomandibulären Region. In: von Piekartz HJM (ed). 2nd edition. Kiefer-Gesichts-und Zervikalregion. Auflage: Thieme, 2015. Pg 212.

Figure 1

Accessory movement in the transverse sliding of the TMJ (temporomandibular joint) towards lateral (A) and with an angulation towards 30° posterior (B). Movement diagram A shows exponential curve (R1-R2) with no limitation when the average movement excursion is 2 mm. The reproduction of ear pain is minimal (P1-P”) (2/10 on a numerical pain rate scale, NPRS). Movement diagram B shows the angulated transverse to lateral, where R1-R2 is more than 50% restricted and the ear pain is stronger (6/10 NPRS), suggestive of lateral pterygoid muscle involvement. Reprinted with permission from Physikalisch Untersuchung von Dysfunktionen der kraniomandibulären Region. In: von Piekartz HJM (ed). 2nd edition. Kiefer-Gesichts-und Zervikalregion. Auflage: Thieme, 2015. Pg 212.

Figure 2

Performance of the neurodynamic test of the mandibular nerve: upper cervical flexion, upper lateral flexion toward the contra-lateral side, mandible lateral deviation in 2.5 cm mouth opening to the contra-lateral side. Right figure reprinted with permission from Hals und Neuroanatomie. In: Prometeus K (ed). 4th edition. Auflage: Thieme; 2015. Pg. 123.

Figure 3

Mandibular distraction mobilisation technique. Copyright Handspring Publishing Limited 2018. Reproduced with permission. Illustrations first published in Temporomandibular Disorders edited by César Fernández-de-las-Peñas and Juan Mesa-Jiménez, Handspring Publishing Limited, 2018.

Figure 4

Intra-oral pincer compression of masseter muscle. Copyright Handspring Publishing Limited 2018. Reproduced with permission. Illustrations first published in Temporomandibular Disorders edited by César Fernández-de-las-Peñas and Juan Mesa-Jiménez, Handspring Publishing Limited, 2018.

Figure 5

Unilateral posterior-anterior mobilization of the upper cervical spine.

Figure 6

Dry needling of the zygomatic muscle (pincer palpation). Copyright Handspring Publishing Limited 2018. Reproduced with permission. Illustrations first published in Temporomandibular Disorders edited by César Fernández-de-las-Peñas and Juan Mesa-Jiménez, Handspring Publishing Limited, 2018.

Figure 7

Example of the laterality test (left image) and basic emotion test training (right image) on a mobile telephone, which may be converted in intervention parameters easily.

Figure 8

Algorithm for the clinical examination and treatment of patients with TMD based on nociceptive pain mechanisms.