Centrode patterns in the lumbar spine. Baseline studies in normal subjects

Area of Science:

• Biomechanics
• Spinal Imaging
• Orthopedics

Background:

• Segmental spinal instability is a common cause of back pain.
• Current methods lack accuracy in quantifying spinal instability.
• Centrode analysis in cadaver studies shows increased length with instability.

Purpose of the Study:

• To describe and validate an in vivo method for precise centrode pattern determination.
• To quantify centrode patterns in normal male volunteers at lumbar spine levels L4-5 and L5-S1.
• To assess the potential clinical utility of centrode analysis for diagnosing spinal instability.

Main Methods:

• Utilized lateral radiographs of the lumbar spine from 21 healthy male volunteers.
• Recorded six spinal positions from full extension to full flexion using high-speed films.
• Employed acetate tracings, contour matching, digitizer, and computer analysis for precise centrode pattern calculation.

Main Results:

• Successfully determined in vivo centrode patterns for lumbar motion segments.
• Measured average centrode lengths of 43.7 mm at L4-5 and 55.9 mm at L5-S1.
• Demonstrated the feasibility of precise in vivo centrode pattern analysis for sagittal plane motion.

Conclusions:

• Precise in vivo centrode pattern analysis of lumbar spine sagittal motion is achievable.
• This technique shows promise as a clinical tool for diagnosing early segmental instability.
• Further studies are needed to confirm its utility in patients with low-back pain.