Cost effective treatment, Dysphagia Therapy, Singapore, Swallowing Problem

Surface Electromyography (sEMG) Fatigue Analysis Comparing Chin Tuck against Resistance (CTAR) Against the Shaker Exercise

CTAR Poster
CTAR Poster

This poster was presented at the recent Dysphagia Research Society 23rd Annual Meeting at Illinois, Chicago, USA (12-14 March 2015).

Title: Surface Electromyography (sEMG) Fatigue Analysis Comparing Chin Tuck against Resistance (CTAR) Against the Shaker Exercise

Abstract:

Both Shaker and Chin Tuck against Resistance (CTAR) exercises were designed to improve swallowing through the strengthening of the suprahyoid muscles. However, a major limitation of the Shaker exercise was its early fatiguing of the sternocleidomastoid (SCM)(White et al., 2008). In this study, we investigated the extent CTAR recruits the suprahyoid and whether it fatigues SCM. Amplitude and fatigue analyses on sEMG data from 39 adults revealed that unlike Shaker exercise, CTAR was able to recruit the suprahyoid muscle, without substantially fatiguing SCM.

Introduction:

  • Shaker exercise increases UES opening by improving contraction of suprahyoid muscles (Shaker et al., 1997).
  • However, patient compliance was poor (50% attrition; e.g., Easterling et al., 2005).
  • Poor compliance of Shaker exercise was linked to muscle fatigue of auxiliary muscles, namely SCM (White et al., 2008). CTAR exercise was a response to this limitation.
  • Preliminary evidence for CTAR (N = 40 healthy adults; Yoon et al., 2014): (a) Greater sEMG values (amplitude) obtained from Suprahyoid during CTAR than during Shaker exercise. (b) Overall, participants reported CTAR as less strenuous.
  • Research Questions:
  1. Yoon et al’.s data was based on 10-sec isometric trials. The actual CTAR and Shaker exercises require 60 secs each. Will evidence on suprahyoid muscle strength still hold for CTAR when exercise duration is increased to 60 secs?
  2. Main disadvantage for Shaker exercise was its fatiguing of auxiliary muscles beyond the suprahyoid, i.e., SCM. Is CTAR able to demonstrate that it does not suffer this same limitation (i.e., fatiguing of SCM)?

Method:

Participants:

  • N = 39 healthy adults (20 males, 19 females; mean age = 29.82, SD = 5.09).
  • Each participant completed CTAR and Shaker twice in randomized counterbalanced order. 4-min rest in between each exercise.

sEMG Recording:

  • Single-use pre-gelled electrode patches used (Figure 1; one placed on suprahyoid, the other on SCM).
  • sEMG collected by MyoTrac Infiniti encoder (2048 Hz).

CTAR Exercise (Figure 2):

  • Seated upright; shoulders not slouched.
  • Executed chin tuck, squeezing an inflatable rubber ball (12 cm diameter) between the base of chin and manubrium sterni for 60 secs.

Shaker Exercise (Figure 3):

  • Lie supine on an exercise mat.
  • Perform a head lift for 60 secs, shoulder not raised.

Data Processing:

First and final 7 secs from each exercise interval discarded to eliminate noise. – MATLAB (Welsch Method) used to generate the power spectra density data.

Results:

  • 2 x 2 ANOVA was conducted on each variable.
  • Suprahyoid registered sig. greater (ps < .001) values during CTAR than Shaker. SCM registered sig. greater (ps < .001) values during Shaker than CTAR.
  • Suprahyoid registered sig. greater (ps ≤ .02) fatigue during CTAR than Shaker. SCM registered sig. greater (ps ≤ .002) fatigue during Shaker than CTAR.
  • Rate of change in fatigue for Suprahyoid: CTAR = Shaker (ps > .10). Rate of change in fatigue for SCM: Sig. lesser (ps ≤ .01) during CTAR than Shaker

Discussion:

  • Converging data across two amplitude measures suggest that motor unit recruitment (thus muscle strength) for Suprahyoid was significantly greater during CTAR.
  • Converging data across four fatigue measures suggest that fatigue in SCM was significantly lesser during CTAR than the Shaker exercise.
  • Extends supporting evidence on CTAR’s usefulness in targeting Suprahyoid (SCM not as actively recruited), when conducted in its full 60-secs duration.
  • Clinical trials of CTAR on dysphagic patients recommended as follow-up.
dysphagia assessment, Objective assessment, Singapore, Teaching

SHAS Special Interest Group Talk: Videofluoroscopy Interpretation Made Easy

Videofluoroscopy_Interpretation_talk_poster Videofluoroscopy_Interpretation_Made_Easy_Registration_Form _1_

I will be conducting a talk titled Videofluoroscopy (VFS) Interpretation Made Easy for Speech-Language & Hearing Association Singapore.

Date: 24 April 2015 (Thursday)

Time: 6.15pm – 8.30pm

Venue:

National University Hospital

Group Therapy Room, Main Building Level 1,

5 Lower Kent Ridge Road, 119074

About this talk:

This talk is a short introduction to Videofluoroscopy (VFS) interpretation and is suitable for both clinicians who are experienced or inexperienced in performing VFS. I will introduce pathophysiologies commonly viewed in VFS with the use visual examples. I will also share on how I analyze VFS systematically, and how to select suitable strategies to be trialed during the procedure accordingly to patient’s presentation.

Outline of the talk:

  • Short introduction about VFS
  • Pathophysiologies viewed in VFS
  • Esophageal phase screening
  • How to interpret VFS systematically rienced clinicians to share their experiences and views on VFS as well rienced clinicians to share their experiences and views on VFS as well.
Cost effective treatment, Dysphagia Therapy, Singapore, Swallowing Problem

Chin Tuck Against Resistance (CTAR) Poster that was awarded first place at the DRS 2013

In March 2013, Mr Jason Khoo (A MSc SLP graduate from NUS) presented this scientific poster on CTAR at the Dysphagia Research Society Meeting at Seattle, Washington, USA in 2013. Little did we expect that CTAR actually drew so much interest at the DRS meeting and was also awarded first place for the Scientific Abstract Poster.

CTAR poster 1

CTAR was awarded first place in Scientific Abstract Poster at DRS 2013
CTAR was awarded first place in Scientific Abstract Poster at DRS 2013

Comparison of suprahyoid muscles activity between chin-tuck-against-resistance (CTAR) and the Shaker exercises

Jason KHOO, Susan J. RICKARD LIOW, YOON Wai Lam

Summary

For patients with pharyngeal dysphagia, therapeutic exercise such as the Shaker exercise to strengthen the suprahyoid muscles is effective in restoring oral feeding. However, observations revealed that the Shaker exercise is physically demanding for the elderly patients, thereby affecting compliance of the exercise goals. A less strenuous exercise, CTAR, was compared to the Shaker exercise by measuring the surface electromyography (sEMG) activity of the suprahyoid muscles during both exercises. The sEMG activity of the suprahyoid muscles during CTAR was similar or superior to the Shaker exercise. Therefore, CTAR exercise has the potential to achieve the same therapeutic effect as Shaker exercise and may improve compliance.

Introduction

Aim: To find out if CTAR is as effective as Shaker exercise in exercising the suprahyoid muscles.

  • The Shaker exercise has been shown to be effective for patients with dysphagia due to incomplete upper esophageal sphincter (UES) opening  (Shaker et al, 2002).
  • Performing Shaker exercise significantly increased the anteroposterior diameter of the UES (Easterling et al, 2005) and significantly reduced post-swallow aspiration (Logemann et al, 2009).
  • A key component of Shaker exercise is in exercising the suprahyoid muscles, thereby strengthening it (Shaker et al, 2002).
  • Easterling et al (2005) found out that muscle discomfort or time constraints were main reasons for the failure of their participants in attaining the Shaker exercise goals.
  • Clinical observations suggest the Shaker exercise may pose a physical challenge for elderly dysphagic with chronic disease (Yoshida et al, 2007).
  • Developing a less strenuous therapeutic exercise would potentially benefit patients who find Shaker exercise physically challenging, thereby facilitating the attainment of the exercise goals.
  • The CTAR exercise, performed in a seated position, is less strenuous as the patient is not required to lift  the weight of her head.
  • Performing the CTAR exercise in a seated position would make it more convenient for dysphagic patients who are actively mobile to comply with, thereby improving compliance.
  • The CTAR will adopt the same regime as Shaker exercise; a set of isometric (sustaining the effort) and isokinetic (repetitions) exercise with equal time base.

Research question: Would the sEMG activity of the suprahyoid muscles be higher during CTAR exercise?

Method

Participants:

N=40 healthy adults (21-40 yrs). Each participant performed a total of 4 exercise tasks, with a minimum 5 minute rest in between each task. The order of the 4 tasks are randomly assigned and counter-balanced across participants.

4 exercise tasks:

  • CTAR isometric
  • CTAR isokinetic
  • Shaker isometric
  • Shaker isokinetic

CTAR exercise (see Figure b):

  • Seated upright in chair
  • An inflatable rubber ball (diameter 12cm) is placed between chin and base of neck to provide resistance
  • Chin tuck against the ball and sustaining it for 10 sec (isometric)
  • Chin tuck against rubber ball for 10 repetitions (isokinetic)

Shaker exercise (see Figure c):

  • Supine position
  • Lift head high enough to see their toes
  • Sustaining the head lift for 10 sec (isometric)
  • Lift head for 10 repetitions (isokinetic)

sEMG (see Figure a):

  • The activity of the suprahyoid muscles was measured using sEMG via an electrode patch attached to the participant’s suprahyoid area

Results

CTAR poster result 1

Discussion

  • The CTAR exercise appears to be similarly effective or superior to Shaker exercise in utilising the suprahyoid muscles.
  • If Shaker exercise is effective in strengthening the suprahyoid muscles and increasing the anteroposterior diameter of the UES, CTAR exercise may be able to achieve a similar or greater effect.
  • CTAR exercise may be a potential alternative for elderly dysphagic patients who find Shaker exercise physically challenging.
  • This study is limited to healthy young adults. Replication of this study on an older population will enable further understanding of the impact of age.
  • Future clinical studies are necessary to evaluate the therapeutic potential of CTAR in dysphagic patients with incomplete UES opening and the compliance of CTAR exercise amongst the elderly patients.