Sunday, December 5, 2010

TMJ disorders and Neck Pain are closely linked. New study shows mechanical and kinematic movement of neck is altered by neck pain.

A recent article (Arch Phys Med Rehabil. 2010 Dec;91(12):1884-90.) showed changes in neck function when pain was present. Neck pain is one of the most frequently helped conditions during neuromuscular treatment of TMD disorders. If treating the pain can return normal function this would be an incredible finding.

The article concludes "Velocity and smoothness of cervical motion were more restricted in patients with chronic neck pain than found previously. Unlike range of motion and other static measurements, these dynamic variables reflect functional cervical motion and therefore contribute to a better understanding of the impairment associated with neck pain. Because the ability to move quickly in response to external stimuli is a commonly occurring phenomenon, this deficit is highly relevant to clinical assessment and management."

The unanswered question is whether the limitation and pain have a common orgin or if the pain is the cause of the changes noted. If the pain alone causes these changes than more debilitating problems would occur over time. An interesting follow-up study would be to examine changes after treatment of pain.

The PPM, Pure Power Mouthguard has been shown to increse flexibility and balance in athletes. A Rutger's study confirmed this. I have frequently seen normalization in pain and function in patients treated with neuromuscular orthotics but these are subjective improvements. This "virtual reality assesment" may be a more objective method to measure improvement in neck function following rehabilatative medicine, physical therapy, chiropractic or osteopathic adjustments and TMD treatment.

Arch Phys Med Rehabil. 2010 Dec;91(12):1884-90.
The effect of neck pain on cervical kinematics, as assessed in a virtual environment.
Bahat HS, Weiss PL, Laufer Y.

Department of Physical Therapy, Faculty of Social Welfare and Health Sciences, University of Haifa, Israel.
Abstract
Sarig Bahat H, Weiss PL, Laufer Y. The effect of neck pain on cervical kinematics, as assessed in a virtual environment.

OBJECTIVE: To compare cervical kinematics during functional motion in patients with neck pain and in asymptomatic participants using a novel virtual reality assessment.

DESIGN: Clinical comparative trial.

SETTING: Participants were recruited from university staff and students, and from a local physical therapy clinic.

PARTICIPANTS: Patients with chronic neck pain (n=25) and asymptomatic participants (n=42).

INTERVENTIONS: Not applicable.

MAIN OUTCOME MEASURES: Kinematic measures (response time, peak and mean velocity, number of velocity peaks, time to peak velocity percentage) were sampled while participants were engaged in the virtual game. Group and motion direction differences were assessed with a 2-way repeated-measures analysis of variance, Tukey-Kramer testing, and contrast analysis when relevant.

RESULTS: Participants with neck pain had lower peak and mean velocities than the asymptomatic participants (P<.0001). They also demonstrated a greater number of velocity peaks, indicating impaired motion smoothness (P=.0036). No significant group differences were found for response time or for time to peak velocity percentage. Cervical rotations were significantly faster and smoother than flexion and extension movements (P<.05). The overall impairment percentage in velocity and smoothness of cervical motion in patients with neck pain ranged from 22% to 44% compared with asymptomatic participants.

CONCLUSIONS: Velocity and smoothness of cervical motion were more restricted in patients with chronic neck pain than found previously. Unlike range of motion and other static measurements, these dynamic variables reflect functional cervical motion and therefore contribute to a better understanding of the impairment associated with neck pain. Because the ability to move quickly in response to external stimuli is a commonly occurring phenomenon, this deficit is highly relevant to clinical assessment and management.

Copyright © 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
PMID: 21112430 [PubMed - in process]