The sacro-iliac joint: A potentially painful enigma. Update on the diagnosis and treatment of pain from micro-trauma.

The sacro-iliac joint (SIJ) located at the transition between the spine and the lower limbs is subjected to major shear forces. Mobility at the SIJ is very limited but increases during pregnancy and the post-partum period. Familiarity with the anatomy and physiology of the SIJ is important.

The mechanism in junctional failure of thoraco-lumbar fusions. Part II: Analysis of a series of PJK after thoraco-lumbar fusion to determine parameters allowing to predict the risk of junctional breakdown.

Purpose: To identify risk factors, in 12 patients with junctional breakdown (JBD) after thoraco-sacral fusions and to test a software locating maximal bending moment on full spine EOS images.

Methods: Twelve patients underwent long fusions for lumbar degenerative pathologies. Preop EOS images were compared to first postop EOS showing JBD.

The mechanism in junctional failure of thoraco-lumbar fusions. Part I: Biomechanical analysis of mechanisms responsible of vertebral overstress and description of the cervical inclination angle (CIA).

Purpose: The purpose of the study is to describe the biomechanical theory explaining junctional breakdowns in thoraco-lumbar fusions, by taking the example of vertebral compression fractures. Also, a new angle, the cervical inclination angle (CIA), describing the relative position of the head at each vertebral level, is presented.

Methods: For the CIA, the data were collected from 137 asymptomatic subjects of a prospective database, containing clinical and radiologic informations.