For type 1 MT curves, the general rule is to fuse only the MT region, posteriorly, anteriorly, or, if occasionally required, circumferentially.
The MT curve is treated from upper to lower end vertebrae by the anterior approach and typically from T3, T4 or T5 down to one or two levels above stable, distally from a posterior route. A helpful measure to select the distal fusion level is to draw the CSVL on the radiograph.
The most proximal lower thoracic or lumbar vertebra that is at all touched by that line is normally an acceptable distal fusion level as long as adequate apical correction can be obtained with posterior fixation.
A challenging curve pattern is a type 1C pattern in which there is complete deviation of the lumbar curve from the midline, but the curve is flexible. Most of these curves can still undergo selective thoracic fusion by either the anterior or posterior route, but further detailed radiographic and clinical assessment is required.
Radiographic ratio parameters of thoracic to lumbar Cobb angle measurements, apical vertebral translation, and apical vertebral rotation must be analysed. When these ratios are much more prominent in the thoracic region than in the lumbar region, a selective thoracic trunk and chest wall should be much more prominent than the corresponding features of the lumbar spine on both upright and forward bending examination.
Lastly, the sagittal plane has a role in whether an anterior or posterior procedure is performed and whether the surgeon would posteriorly instrument and correct the concavity (hypokyphosis or normal kyphosis) or convexity (hyperkyphosis) alignment first. All of these factors are analysed in selecting the approach, instrumentation techniques, and upper and lower fusion levels for each patient.
The Thoracic curve is one of the most common Scoliotic curves. It affects the upper spine and usually curves to the right side of the body.
The vertebrae experience severe rotation with this curve, which results in rib abnormalities and very rarely, cardiopulmonary dysfunction. A right Thoracic curve is usually accompanied by smaller curves both above and below the largest curve.
One of the most common patterns in Idiopathic Scoliosis, 90% occur on the right side.
Scoliosis Thoracic Curve