Alterations in kinematics of temporomandibular joint associated with chronic neck pain.

BACKGROUND: Temporomandibular disorder (TMD) is an umbrella term for pain and dysfunction of the temporomandibular joint (TMJ) and its associated structures. Patients with TMD show changes in TMJ kinematics and masticatory muscle activation. TMD is commonly comorbid with non-specific chronic neck pain (NCNP), which may be one of the risk factors for TMD. OBJECTIVES: This study aimed to investigate whether patients with NCNP have altered TMJ kinematics and masticatory muscle activity. METHODS: This was a cross-sectional exploratory study including 19 healthy participants and 20 patients with NCNP but without TMD symptoms. TMJ kinematics was measured during mouth opening and closing, jaw protrusion and jaw lateral deviation. Surface electromyography was used to record the muscle activity of the anterior temporalis, masseter, sternocleidomastoid and upper trapezius while clenching. Furthermore, cervical posture, cervical range of motion (ROM) and pressure-pain threshold of the neck and masticatory muscles were measured. RESULTS: Compared with the healthy group, the NCNP group showed significantly reduced upper cervical rotation ROM (p = .041) and increased condylar path length (p = .02), condylar translation (opening p = .034, closing p = .011) and mechanical pain sensitivity of the upper trapezius (p = .018). Increased condylar translation was significantly correlated with reduced upper cervical mobility and poor cervical posture (r = -0.322 to -0.397; p = .012-.046). CONCLUSION: Increased condylar translation and path length in patients with NCNP may indicate poor control of TMJ articular movement, which may result from neck pain or may be a compensation for limited neck mobility. Evaluation of excessive TMJ translation may be considered in patients with NCNP.

Effects of Kinesio tape on supporting medial foot arch in runners with functional flatfoot: a preliminary study.

This study aimed to evaluate the anti-pronation effects of Kinesio tape on flexible flatfoot during running. Nine volunteers participated in a crossover trail of two conditions: with Kinesio tape (KT) or without taping (NT). The running consisted of 9 stages of different inclines on a treadmill over 28 minutes. Navicular drop distance (NDD) was measured before and after the running. Electromyography, the relative plantar pressure, Rating of Perceived Exertion and Visual Analogue Scale were recorded at each stage. After the application of Kinesio tapes over the tibialis posterior and transverse arch, the NDD reduced significantly and the relative posterior pressure reduced during stage 8. Without taping, the NDD decreased slightly after exercise. Comparing between conditions, the tibialis anterior were more activated with Kinesio tape in stages 4 and 5. During the latter half of the running, the medial gastrocnemius and peroneus longus reduced their activity in the KT and NT conditions respectively. In conclusion, the Kinesio tapes intended to facilitate the tibialis posterior and reinforce the transverse arch can reduce NDD in individuals with flexible flatfoot immediately after application, and increase muscle activity of their tibialis anterior during the first 15 minutes of the running.