Research article

Use of a Cybex NORM dynamometer to assess muscle function in patients with thoracic cancer

Andrew Wilcock¹ , Matthew Maddocks² , Mary Lewis¹ , Paul Howard¹ , Jacky Frisby¹ , Sarah Bell¹ , Bisharat El Khoury¹ , Cathann Manderson¹ , Helen Evans² and Simon Mockett^{^ 2}

¹Hayward House Macmillan Specialist Palliative Cancer Care Unit, Nottingham University Hospitals NHS Trust, Nottingham, UK

²Division of Physiotherapy Education, University of Nottingham, Nottingham, UK

author email corresponding author email^Deceased

BMC Palliative Care 2008, 7:3doi:10.1186/1472-684X-7-3

Published:	10 April 2008

Abstract

Background

The cachexia-anorexia syndrome impacts on patients' physical independence and quality of life. New treatments are required and need to be evaluated using acceptable and reliable outcome measures, e.g. the assessment of muscle function. The aims of this study were to: (i) examine the acceptability and reliability of the Cybex NORM dynamometer to assess muscle function in people with non-small cell lung cancer or mesothelioma; (ii) compare muscle function in this group with healthy volunteers and; (iii) explore changes in muscle function over one month.

Methods

The test consisted of 25 repetitions of isokinetic knee flexion and extension at maximal effort while seated on a Cybex NORM dynamometer. Strength and endurance for the quadriceps and hamstrings were assessed as peak torque and total work and an endurance ratio respectively. Thirteen patients and 26 volunteers completed the test on three separate visits. Acceptability was assessed by questionnaire, reliability by intraclass correlation coefficients (ICC) and tests of difference compared outcomes between and within groups.

Results

All subjects found the test acceptable. Peak torque and work done were reliable measures (ICC >0.80), but the endurance ratio was not. Muscle function did not differ significantly between the patient and a matched volunteer group or in either group when repeated after one month.

Conclusion

For patients with non-small cell lung cancer or mesothelioma, the Cybex NORM dynamometer provides an acceptable and reliable method of assessing muscle strength and work done. Muscle function appears to be relatively well preserved in this group and it appears feasible to explore interventions which aim to maintain or even improve this.