MODULE 1 Lumbar Spine
History, persistent history, PM history, family history Chief Complaint – O, P, P, Q, R, S, T Physical examination – orthopedic, neurological Differential diagnosis Tests to limit differential diagnosis INTRODUCTION When to x-ray
Risks versus benefits ratio Cost versus benefit ratio When differential diagnosis includes something to: > rule in, rule out or > monitor a known condition by x-ray Who gets x-ray
Shoot Series
ABC’S Technical evaluation Search pattern
Normal Anatomy
Mensuration Lumbar spine Disc height Hurxthal - measures mid point of each endplate >easy >can’t account for extension or flexion malposition >distance
Farfan Anterior height ratio (AHR) = Anterior height Diameter Posterior height ratio (PHR) = Posterior height Diameter DH = AHR PHR More complex posterior anterior Research use height Dheight
Both Measurements Great variation exists Rotation >40 o or lateral flexion >20 o leads to unreliable results
Decrease disc height causes Degeneration Surgery (i.e. discectomy) Chemonucleolysis Infection Congenital hypoplasia
Poor correlation between loss of disc height and pain.
IVD Angles Lines tangential to the endplates extend until intersection Measuring angle Little predictability Alterations may occur >Antalgia >Muscle imbalance >Poor posture >Early DJD >Facet syndrome may increase angle >Disc herniation may decrease angle
Lumbar Lordosis Top of L1 and S1 used or bottom of L5 Draw perpendicular to tangential lines Measure angle of intersection Great variety 50 o -60 o average
Lumbosacral lordosis angle and sacral inclination not useful.
Lumbosacral Angle (Sacral base angle, Ferguson’s angle) Tangential sacral base Horizontal line Measure angle of intersection 41 o +/- 7 o >It has been suggested that increased angle leads to increased shearing and compressive forces at the facets >No increase in anterolisthesis noted
Static Vertebral Malpositions Flexion Extension Lateral flexion Rotation Anterolisthesis Retrolisthesis Laterolisthesis
Lumbar Gravity Line (Ferguson’s, weight bearing, Ferguson’s gravity) Center of L3 Plumb line Should intersect anterior sacral margin +/- 10mm
McNab’s Line High number’s of asymptomatic patients make this line’s usefulness doubtful Was originally used on recumbent films weight bearing may alter utility
Hadley’s Curve AP and obliques views used Interuption of the line may indicate: >Rostral/caudal migration >Extension malposition >Rotational malposition
VanAkkerveeken and flexion and extension have been largely replaced by the more sensitive comp/distraction study.
Lateral Bending Study May suggest ligament laxity and/or muscle spasm Poor correlation between this and clinical picture
Meyerding Replaced by the more useful percentage method Anteriority sacral base length = % of antero
Ullmann’s Line Tangential to sacral base Perpendicular to and coincide with anterior sacral prominence L5 should be at or posterior to line, if anterior, it represents anterolisthesis Note: decreased lordosis may produce false positive
Interpediculate Distribution and Eisenstein’s and canal body ratio (unreliable) measure for central canal stenosis Small numbers are suggestive only CT, MR for definitive diagnosis