Spinal landmark depth in relation to body mass index

Area of Science:

• Anatomy
• Biomedical Imaging
• Orthopedics

Background:

• Accurate identification of spinal landmarks is essential for manual therapy.
• Understanding how body mass index (BMI) affects landmark depth is important for palpation accuracy.

Purpose of the Study:

• To quantify the depth of lumbar spinous and transverse processes.
• To investigate the relationship between landmark depth and body mass index (BMI) in males and females.

Main Methods:

• 105 subjects underwent lumbar magnetic resonance imaging (MRI).
• Four blinded examiners measured spinous and transverse process depths on T1-weighted MRI images.
• Linear mixed-effects models analyzed the relationship between depth and BMI, stratified by gender.

Main Results:

• Mean landmark depths ranged from 22.77 mm (L1 spinous process) to 69.41 mm (L4 transverse process).
• A statistically significant linear relationship between increased landmark depth and BMI was observed for all landmarks in females.
• This correlation was significant only for spinous processes in males.

Conclusions:

• Landmark depth in the lumbar spine increases with subject BMI.
• While BMI is a factor, other variables likely influence the depth and palpability of spinal landmarks.
• These findings suggest a need for clinicians to consider individual variations in BMI when interpreting palpation findings.