Ultrasound-Assisted Brace Casting for AIS
Condition: Scoliosis; Adolescence
MeSH terms: Scoliosis
Study type: Interventional
Phase: Early Phase 1

Summary: 
      Adolescent Idiopathic Scoliosis (AIS) is a three-dimensional deformity of the spine
      associated with vertebral rotation. Brace treatment is the most commonly used non-surgical
      treatment. To obtain the best possible outcome, the best in-brace correction within the
      patient's accepted tolerance must be provided. However, in the existing clinical practice,
      the immediate in-brace correction cannot be measured during the design and fitting of the
      brace because the correction is determined using a radiograph. This study is to evaluate the
      effect of applying ultrasound to measure the stimulated in-brace correction during brace
      casting.
    

Detailed description: 
      Background: Adolescent Idiopathic Scoliosis (AIS) is a three-dimensional deformity of the
      spine associated with vertebral rotation. Brace treatment is the most commonly used
      non-surgical treatment. To obtain the best possible outcome, the best in-brace correction
      within the patient's accepted tolerance must be provided. However, in the existing clinical
      practice, the immediate in-brace correction cannot be measured during the design and fitting
      of the brace because the correction is determined using a radiograph.

      Objectives: The objective of this study is to use ultrasound method to determine the optimum
      tolerable applied pressure level that can provide maximum in-brace correction.

      Procedure:

      Control Group: In the traditional method, each brace will be constructed using a plaster cast
      of the patient's trunk. Before the plaster cast hardens, the subject will lie on a casting
      board with multiple brace pads applied to correct the curve(s). The trim lines, pad
      placement, and areas of relief are then determined by the orthotist and guided by the
      curvature seen on the pre-brace PA spine radiograph.

      Intervention Group: Before applying the plaster, subjects will lie on the custom designed
      frame. Two ultrasound scans will be performed and the average Cobb value will be used as the
      baseline. Multiple adjustable brace pads, each allowing for 6° of freedom and variable
      forces, will be applied to the patients' body according to orthotist suggestion. The apical
      brace pad that is used to control the major curve will be marked relative to the casting
      board as the reference location. The major pressure pad will be moved up 1 inch, then down 1
      inch relative to the reference location. The 1 inch increment corresponds to the casting
      board, but finer adjustment is available. Two repeated ultrasound scans will be performed at
      each pad location (total 3 locations), and the average in-brace Cobb values will be estimated
      to determine optimum apical brace pad location. Next, pressure will be increased
      incrementally up to the tolerance level of the subject; this will be done by inflating the
      bladder at the apical brace pad. Another two ultrasound scans will then be performed to
      confirm that the maximum in-brace Cobb value is obtained. The orthotist will use this
      configuration to set the pad size and location once the plaster cast has been applied.
    

Intervention name(s): Ultrasound Assisted Group
Intervention type(s): Device
Intervention description(s): A custom brace standing frame, a medical ultrasound system, a custom pressure measurement system, and in-house Ultrasound measurement software were used to assist brace casting for the intervention group.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Health Services Research
Keywords: Adolescent Idiopathic Scoliosis; Brace Treatment; Ultrasound Imaging