POSTERIOR ELEMENT MORPHOLOGY AND DEGENERATIVE LUMBAR SPONDYLOLISTHESIS

Autor: Sung-Soo Kim, Min-Keun Yoon, Bong-Keun Park, Ki-Tae Kwon, Myung-Sang Moon, Min-Suk Park
Rok vydání: 2015
Předmět:
Zdroj: Journal of Musculoskeletal Research. 18:1550001
ISSN: 1793-6497
0218-9577
DOI: 10.1142/s0218957715500013
Popis: Study design: Retrospective radiographic studies on lumbar facet morphology, and facet and laminar inclination angles. Objectives: To investigate the effect of the facet morphology, facet and laminar inclination angles on development of the segmental instability and spondylolisthesis. Summary of background data: Many previous papers related with the facet shape on pathogenesis of the degenerative instability and spondylolisthesis were published. Most authors interpreted that the facet morphology in the pathogenesis of the spondylolisthesis was a factor secondary to facet joint osteoarthritis, and was not the primary one. None dealt the effect of facet shape and laminar inclination on slippage severity. Method: The subject materials were 50 patients (10 males and 40 females) with degenerative spondylolisthesis, treated between 1999 and 2013. Simple radiograms were utilized for assessment. Facet joints were classified by Tsunoda et al., based on its developmental shape and alignment on radiograms; X, M, and W types. Also the laminar inclination and facet inclination angles were measured. Results: Among 50 patients 45 had anterolisthesis with (forward flexion instability) and only five had retrolisthesis (extension instability). In 45 cases of anterolisthesis, there were 24 "X" types, 4 "M" types, and 17 "W" types, while in 5 cases of retrolisthesis there were 3 "X" and 2 "M" types. In 45 cases of anterolisthesis, 24 with "X" type facets had Myerding's grade I slip, and one had grade II slip; Among the 4 "M" types two had grade I slip and two had grade II slip, while among 17 "W" type, there were four grade I slip, 11 grade II slip, and two grade III slip. 13 out of the 16 anterolisthesis over grade II slip had "W" type facets. Vertebra with "W" type facets had average 130° laminar inclination angle and 122° facet inclination angles, while "X" and "M" type facets had less inclination of both angles. Conclusion: The defective facet morphology and laminar inclination angle of the lower lumbar spine can be the predisposing factor of development and slip progress of the degenerative anterolisthesis.
Databáze: OpenAIRE