Vertebral height restoration following kyphoplasty.

ABSTRACT

BACKGROUND: Kyphoplasty is a minimally invasive surgery developed to restore height and stabilize painful vertebral compression fractures (VCFs). Only small retrospective studies have addressed the correlation between the degree of vertebral height restoration as it relates to pain relief and postoperative activity levels. No definitive correlations have been established. The objective of this analysis is to determine how height restoration correlates with improvements in pain, disability and quality of life. METHODS: We assessed outcomes following kyphoplasty in 59 Medicare-eligible patients with 1-3 painful VCFs between T5 and L5 due to osteoporosis or cancer. Pre and postoperative lateral radiographs were available for fifty-nine patients and were used to measure anterior, middle and posterior vertebral body (VB) heights. The Visual Analog Scale (VAS) [range 0 (none) to 10 (worst)] was used to prospectively measure back pain pre and post-operatively in all patients. Pre and post-operative measurements of disability and quality of life were retrospectively collected using the Roland Morris Disability Index (RMDI) [range 0 (no disability) to 24 (high disability)] and EuroQol5-Domain scale (EQ5D) [range -0.11 (poor quality of life) to 1.0 (perfect health)]. Pearson correlations and linear regression models were analyzed for association of VB height improvement with outcomes. RESULTS: Neither Pearson correlations (r coefficient range 0.001-0.152) nor linear regression models (R2 value range 0.0002-0.1133) revealed correlation or association between VB height improvements and outcomes. CONCLUSIONS: This is one of the largest studies to date assessing associations of VB height restoration following kyphoplasty with prospective measurements of pain and retrospective evaluation of disability and quality of life using validated instruments. Although a majority of patients in this cohort demonstrated increased vertebral heights and significant improvements in outcomes, none of the outcomes showed association with height improvements. Regardless of vertebral height improvements, most patients had improved pain, function and quality of life.