Anatomy and Physical Examination of the Lower Back Sports Medicine Fellowship Uniformed Services University of the Health Sciences

Objectives Review the functional anatomy of Lumbar spine Review Physical Examination of LS spine Correlate clinico-pathologic dx with pertinent physical findings

Epidemiology of back pain The most common musculoskeletal disorder in industrialized societies Second only to common cold as cause of lost work time Estimated that ~ 80% of population will experience at least one disabling episode of back pain at some time during their lifetime The most common cause of disability in persons under the age of 45

Epidemiology of back pain (cont.) When compensation from lost work, long-term disability, and medical and legal expenses are considered, is the most costly of all medical dx’s

PATIENT HISTORY “OPQRSTU” Onset Palliative/Provocative factors Quality Radiation Severity/Setting in which it occurs Timing of pain during day Understanding - how it affects the patient Onset Palliative/Provocative factore Quality Radiation Severity/Setting in which it occurs Timing of pain during day Understanding - how it affects the patient

“Red Flags” in back pain Hx of cancer Unrelenting nocturnal pain Weight loss Fever, chills, night sweats Age < 15 or > 50 Neurologic deficits Decreased motor and/or sensory innervation Urinary and/or fecal incontinence

Anatomy Vertebra Body, anteriorly Functions to support weight Vertebral arch, posteriorly Formed by two pedicles and two laminae Functions to protect neural structures

Ligaments Anterior longitudinal ligament Posterior longitudinal ligament Interspinous ligament Supraspinous ligament Ligamentum flavum

Physical Examination Inspection Palpation Bony Soft Tissue Range of Motion Neurologic Examination Special Tests

Inspection Observe for areas of erythema Infection Long-term use of heating element Unusual skin markings Café-au-lait spots Neurofibromatosis Hairy patches (Faun’s beard) Lipomata Spina bifida

Inspection (cont.) Posture Shoulders and pelvis should be level Bony and soft-tissue structures should appear symmetrical Normal lumbar lordosis Exaggerated lumbar lordosis is common characteristic of weakened abdominal wall

Bone Palpation Palpate L4/L5 junction (level of iliac crests) Palpate spinous processes superiorly and inferiorly S2 spinous process at level of posterior superior iliac spine Absence of any sacral and/or lumbar processes suggests spina bifida Visible or palpable step-off indicative of spondylolisthesis

ANTERIOR PALPATION

Soft Tissue Palpation 4 clinical zones Midline raphe Paraspinal muscles Gluteal muscles Sciatic area Anterior abdominal wall and inguinal area

Range of Motion Flexion Extension Lateral Bending Rotation

Flexion - 80º Extension - 35º Side bending - 40º each side Twisting - 3-18º

Neurologic Examinaion Includes an exam of entire lower extremity, as lumbar spine pathology is frequently manifested in extremity as altered reflexes, sensation and muscle strength Describes the clinical relationship between various muscles, reflexes, and sensory areas in the lower extremity and their particular cord levels

Neurologic Examination (T12, L1, L2, L3 level) Motor Iliopsoas - main flexor of hip With pt in sitting position, raise thigh against resistance Reflexes - none Sensory Anterior thigh

Neurologic Examination (L2, L3, L4 level) Motor Quadriceps - L2, L3, L4, Femoral Nerve Hip adductor group - L2, L3, L4, Obturator N. Reflexes Patellar - supplied by L2, L3, and L4, although essentially an L4 reflex and is tested as such

L2, L3, L4 testing

Neurologic Examination (L4 level) Motor Tibialis Anterior Resisted inversion of ankle Reflexes Patellar Reflex (L2, L3, L4) Sensory Medial side of leg

Neurologic Examination (L5 level) Motor Extensor Hallicus Longus Resisted dorsiflexion of great toe Reflexes - none Sensory Dorsum of foot in midline

Neurologic Examination (S1 level) Motor Peroneus Longus and Brevis Resisted eversion of foot Reflexes Achilles Sensory Lateral side of foot

Special Tests Tests to stretch spinal cord or sciatic nerve Tests to increase intrathecal pressure Tests to stress the sacroiliac joint

Tests to Stretch the Spinal Cord or Sciatic Nerve Straight Leg Raise Cross Leg SLR Kernig Test

Test to increase intrathecal pressure Valsalva Maneuver Reproduction of pain suggestive of lesion pressing on thecal sac

Tests to stress the Sacroiliac Joint Pelvic Rock Test FABER Test

Flexion A- Bduction External Rotation

Non-organic Physical Signs (“Waddell’s signs”) Non-anatomic superficial tenderness Non-anatomic weakness or sensory loss Simulation tests with axial loading and en bloc rotation producing pain Distraction test or flip test in which pt has no pain with full extension of knee while seated, but the supine SLR is markedly positive Over-reaction verbally or exaggerated body language Waddell, et al. Spine 5(2):117-125, 1980.

Hoover Test Helps to determine whether pt is malingering Should be performed in conjunction with SLR When pt is genuinely attempting to raise leg, he exerts pressure on opposite calcaneus to gain leverage