Evidence based medicine: analysis of Scheuermann kyphosis.

Study Design: : A review of the current literature using evidence-based medicine (EBM) regarding etiology, natural history, and treatment of Scheuermann kyphosis.

Objective: : To provide current concepts for the rational evaluation and treatment of Scheuermann kyphosis supported by EBM.

Summary Of Background Data: : The literature concerning etiology, natural history, and treatment of Scheuermann disease has mixed views and recommendations, most of which are not strongly supported with levels of evidence.

Scheuermann's kyphosis.

Scheuermann's disease is the most common cause of structural kyphosis in adolescents. The kyphotic deformity is frequently attributed to "poor posture," resulting in delayed diagnosis and treatment. Indications for treatment remain somewhat debated, because the true natural history of the disease has not been clearly defined.

Distal junctional kyphosis of adolescent idiopathic thoracic curves following anterior or posterior instrumented fusion: incidence, risk factors, and prevention.

Study Design: This is a retrospective multicenter analysis of a subset of 375 patients with thoracic adolescent idiopathic scoliosis (AIS) treated with either anterior (238) or posterior (137) fusion with preoperative or postoperative distal junctional kyphosis (DJK) >or=10 degrees .

Objectives: To determine the incidence of DJK before and after surgery in patients with AIS undergoing either anterior or posterior thoracic fusion, and provide recommendations for prevention.

Summary Of Background Data: DJK following surgical treatment for AIS may result in pain, imbalance, and unacceptable deformity.

A posterior tether for fusionless modulation of sagittal plane growth in a sheep model.

Study Design: This was an in vivo and in vitro investigation of a minimally invasive posterior tether system for fusionless modulation of sagittal plane growth in an immature sheep model.

Objective: To determine whether fusionless modulation of spinal growth in the sagittal plane of an immature sheep model can be successfully performed.

Summary Of Background Data: Scheuermann's disease has been reported to affect 1% to 8% of the pediatric population.

Single-rod versus dual-rod anterior instrumentation for idiopathic scoliosis: a biomechanical study.

Study Design: Anterior single- and dual-rod instrumented human and ovine thoracolumbar spines, with and without structural interbody support (SIS), were biomechanically tested and compared in flexion, lateral bending, and torsion.

Objective: To determine significant differences in global stiffness of the constructs in an attempt to clarify specific indications for each in the treatment of spinal deformities.

Summary Of Background Data: Single- and dual-rod anterior systems have been used without any consensus as to indications for one versus the other.

A biomechanical study of regional endplate strength and cage morphology as it relates to structural interbody support.

Study Design: An in vitro biomechanical investigation to quantify the endplates resistance to compressive loads, in the thoracic and lumbar spine. Comparisons were made to determine the regional strength of the endplate, the optimal size and geometry of interbody support, and the effects of endplate removal on structural strength.

Objectives: To biomechanically assess the regional variation of endplate strength in the thoracic and lumbar spine, the optimal geometry and cross-sectional area for structural interbody support, and endplate preparation techniques with respect to endplate failure or subsidence.

Anterior single-rod instrumentation of the thoracic and lumbar spine: saving levels.

Study Design: To evaluate the ability of single-rod anterior instrumentation to save or preserve fusion levels and improve thoracic hypokyphosis in patients with adolescent idiopathic thoracic, thoracolumbar, or lumbar scoliosis.

Objective: To provide indications for single anterior rod instrumentation for the treatment of adolescent idiopathic scoliosis and demonstrate effectiveness in properly selected cases.

Summary Of Background Data: Posterior multisegmented dual rod instrumentation is the most commonly used instrumentation for the surgical treatment of adolescent idiopathic scoliosis.