Echotexture in Following Muscle Fibrosis
Condition: Congenital Muscular Torticollis
MeSH terms: Torticollis
Study type: Observational

Summary: 
      Objective: To document the sternocleidomastoid (SCM) muscle fibrosis in congenital muscular
      torticollis (CMT) infants with quantified echotexture and measured thickness during the
      treatment course.

      Design: Cohort study. Setting: Rehabilitation department in a tertiary care hospital.
      Participants: Infants with clinical diagnosis of CMT, without any neurological presentation,
      cervical spin abnormality, and developmental dysplastic hip problem, were recruited in the
      study.

      Intervention: All subjects had physiotherapy for at least 3 months. They underwent at least
      two times of clinical assessment and ultrasonographic examination (1) for bilateral SCM
      muscles during the follow-up period.

      End of follow-up: Subjects who still had prominent clinical presentations after physiotherapy
      for 6 months or were older than 1 year would receive surgery. Subsided presenting clinical
      features determined by the clinician was the other end-point of this investigation.

      Main Outcome Measures: The K value, derived from the difference of echo intensities (2)
      between the involved and uninvolved SCM muscles on longitudinal sonograms, was used to
      represent the severity of muscle fibrosis in CMT infants. Bilateral SCM muscle thickness and
      involved-to-uninvolved thickness ratio (Ratio I/U) were also obtained from longitudinal
      sonograms. Clinical outcome was also recorded.
    

Detailed description: 
      1. An experienced sonographer performed ultrasonographic examination with the subject in
           the supine position and heads rotated contralaterally to the examination side. A 5-12
           MHz linear-array ultrasound transducer was used to observe both longitudinal and
           transverse views of bilateral SCM muscles for each subject. The ultrasound system
           settings, including gain (86%), monitor dynamic range (70 dB), and depth (2 cm), were
           kept constant throughout the study.

        2. The echo intensity was determined by computer-assisted gray scale analysis and was
           calculated in MATLAB 2006b. The mean echo intensity of every pixel in the region of
           interest and the K value developed to compare sonograms between different individuals or
           between different times in the same subject were estimated as the previous study (PMID:
           22215768)
    

Intervention name(s): Ultrasonographic examination
Intervention type(s): Other
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Convenience sample of infants in both gender with congenital muscular torticollis, are
        reviewed by the exclusion criteria (please see below). Subjects, whose parents are willing
        to sign the informed consent and fit our inclusion/exclusion criteria are prospectively
        enrolled in this study.

        Age, gender distribution, body weight (BW), body length (BL), affected muscle side,
        follow-up period, and interval between two visits were also recorded.

        Physiotherapy of passive stretching of the involved muscle, positioning, and massage were
        capable of diminishing the development of scoliosis and facial asymmetry in the future.
      
Keywords: Ultrasonography; echotexture; K value; SCM muscles; CMT infants