2014년 8월 5일 화요일

Preoperative Risk Factors for Recurrent Lumbar Disc Herniation in L5-S1. 2014

J Spinal Disord Tech. 2014 Aug 1. [Epub ahead of print]


BACKGROUND CONTEXT::
Although numerous studies have reported on recurrent lumbar disc herniation (rLDH), few have reported on recurrence of L5-S1 level.

PURPOSE::
We investigated whether the preoperative risk factors, such as disc degeneration, disc height, sagittal range of motion (sROM), width of L5 vertebral transverse process, and iliac crest height, have any effect on recurrent lumbar disc herniation (rLDH) in L5-S1.

STUDY DESIGN::
A retrospective case control study.

PATIENT SAMPLE::
Four hundred sixty seven patients were enrolled in this study.

OUTCOME MEASURES::
The disc degeneration, disc height, sROM, width of L5 vertebral transverse process, and iliac crest height were calculated using magnetic resonance imaging (MRI) and simple radiography.

METHODS::
We compared the clinical parameters (age, sex, body-mass index, symptom duration, diabetes, smoking, preoperative visual analogue scale, herniation type, annular defect size) and preoperative radiologic parameters (disc degeneration, disc height, sROM, relative width of L5 vertebral transverse process (RT), iliac crest height index) of recurrent and non-recurrent groups.

RESULTS::
Patient with rLDH had its onset 39.4±17.9 months (7-90 mo) after primary surgery. Of the 39 rLDH cases, herniation was ipsilateral to previous LDH in 29 patients and contralateral in 10. Multiple logistic regression analysis showed that moderate disc degeneration with preserved height (group B), a large sROM, a small RT, a low IHI and being male were significant risk factors for rLDH.

CONCLUSIONS::
Moderate disc degeneration, a large sROM, a small RT, and a low IHI are biomechanical risk factors of rLDH in L5-S1. The results also suggested being male and having a large annular defect increase recurrence after discectomy, especially in cases of ipsilateral rLDH.