Clinical classification of posterior trans-intervertebral space osteotomy in kyphotic and scoliokyphotic spinal deformity

English Keywords:Trans-intervertebral space osteotomy  Spinal osteotomy  Osteotomy classification

English Abstract:

  【Abstract】 Objectives: To clarify the definition of trans-intervertebral space osteotomy (TIO) and to propose a clinical classification of TIO based on the extent of osseous resection. Methods: The clinical data of 30 patients of kyphotic and kyphoscoliotic spinal deformity underwent TIO correction surgery from January 2003 to December 2012 [12 males and 18 females, aged from 29 to 69 years old (51.4±10.4 years old)] were included. According to the intraoperative extent of osseous resection andthe involvedanatomical structures,the TIO was classified into three main types and two additional subtypes (plus type): type Ⅰ, the resection included posterior facet joints with or without the intervertebral disc; type Ⅱ, the resection included the facet joints, intervertebral disc, and bony wedge of adjacent vertebra including either adjacent endplate; type Ⅲ, the resection included facet joints, intervertebral disc, and bony wedge of inferior vertebra including pedicle. The type Ⅱ and type Ⅲ had plus type (+ type), respectively. Five spinal surgeons evaluated and classified the cases in sequence according to the above-mentioned classification to collect the evaluation data. Two weeks later, the same five surgeons conducted a second evaluation and classified all the same cases in a different order and their evaluation results were collected again. Fleiss′ Kappa coefficients were performed to evaluate the reliability and reproducibility of the classification. Results: There were 15 cases of type Ⅰ TIO, 6 cases of type Ⅱ, 3 cases of type Ⅱ+, 4 cases of type Ⅲ and 2 cases of type Ⅲ+ among the 30 cases. The inter-observer reliability with a Kappa coefficient of 0.806-0.953; the inter-observer reliability with a Kappa coefficient of 0.837-0.953, indicating a satisfying reliability and reproducibility. Conclusions: The proposed clinical TIO classification was practical and validated reliable. It could be utilized for outcome analyze for studies of various TIO techniquesas basic theory, which contributing to the surgical treatment of kyphotic and scoliokyphotic spinal deformity.