Congenital muscular torticollis: the reliability of visual estimation in the assessment of cervical spine active rotation and head tilt by physiotherapists and the impact of clinical experience

Abstract

There is a lack of reliable and valid measurement tools to assess neck function in infants with congenital muscular torticollis, and most physiotherapists use visual estimation, which has not been adequately tested for reliability in this population. We examined the reliability of visual estimation of head tilt and active neck rotation in the upright position, on infants with congenital muscular torticollis by physiotherapists. We recruited 31 infants and 26 physiotherapists. Therapists rated videos of infants’ head position in the frontal plane (tilt) and transverse plane (active rotation) using visual estimation, on two occasions at least one week apart. Overall, inter-rater reliability was good (mean ICC, 0.68 ± 0.20; mean SEM, 5.1° ± 2.1°). Rotation videos had better reliability (mean ICC, 0.79 ± 0.14) than head tilt videos (mean ICC, 0.58 ± 0.20). Intra-rater reliability was excellent (mean ICC, 0.85 ± 0.08). Both head tilt and rotation had excellent reliability (mean ICC, 0.84 ± 0.08 for head tilt and 0.85 ± 0.09 for rotation). There was no correlation between intra-rater reliability and clinical experience.

Conclusion Visual estimation had excellent intra-rater reliability in the assessment of neck active rotation and head tilt on infants with congenital muscular torticollis. Visual estimation had acceptable inter-rater reliability in the assessment of neck active rotation but not of head tilt. There was a wide variation in reliability with no correlation between reliability and clinical experience. Assessment tools for head tilt that are more psychometrically robust should be developed.

What is Known:
• A thorough assessment of infants presenting with torticollis is essential, using assessment tools with robust psychometric properties
• Visual estimation is the most commonly used method of assessment of neck function in infants with torticollis
What is New:
• Visual estimation had excellent intra-rater reliability in the assessment of neck active rotation and head tilt in the upright position in videos of infants and acceptable inter-rater reliability in the assessment of rotation but not of head tilt
• Physiotherapists’ clinical experience had minimal relationship with reliability

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Abbreviations

CI:

Confidence interval

CMT:

Congenital muscular torticollis

CSp:

Cervical spine

ICC:

Intraclass correlation coefficient

ROM:

Range of motion

Rot :

Rotation

SCM :

Sternocleidomastoid muscle

SEM:

Standard error of measurement

SD:

Standard deviation

SF:

Side-flexion

VE:

Visual estimation

VLE:

Virtual learning environment

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Funding

This study received funding from the Temple Street Foundation, Dublin 1, Ireland.

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All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by AS; AS drafted the manuscript; All authors contributed to the manuscript and approved the final version for publication.

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Correspondence to Anthea Seager.

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The authors declare that they have no conflict of interest.

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Ethical approval was granted by the Children’s Health Ireland at Temple Street and Royal College of Surgeons in Ireland Research Ethics Committees.

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Informed consent was obtained from all participating physiotherapists and parents/guardians of infants included in the study. Permission to publish was obtained from the parents of the infant illustrated in Fig. 1.

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Seager, A., Meldrum, D., Conroy, R. et al. Congenital muscular torticollis: the reliability of visual estimation in the assessment of cervical spine active rotation and head tilt by physiotherapists and the impact of clinical experience. Eur J Pediatr 179, 1823–1832 (2020). https://doi.org/10.1007/s00431-020-03691-8

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Keywords

  • Congenital muscular torticollis
  • Visual estimation
  • Assessment
  • Reliability
  • Clinical experience
  • Physical therapy