Examine the spine visually for asymmetry, scoliosis, kyphosis, gluteal atrophy, masses, scars or other deformities. It is important to assess the patient in a standing position and to note the symmetry of iliac crest heights.
Straight-Leg Raise: With the patient supine, the examiner lifts the leg so that the hip is flexed and knee is extended. A positive test is reproduction between the angles of 20 to 60 of reported radicular pain beyond the knee from about, and suggestive of a lumbosacral radiculopathy.
FABERE (Patrick’s) Test: The patient is supine with the knee flexed and crossed so that the ankle rests on the contralateral knee. The examiner then applies downward forces to the knee and contralateral hip. The hip is initially flexed, abducted and externally rotated and the examiner’s force extends the hips; hence the acronym FABERE. A positive test reproduces the patient’s pain and is suggestive of sacroiliac joint dysfunction.
Gaenslen’s Test: The patient is supine on the edge of the table such that the leg and buttocks off of the table and grasps their hands around the contralateral leg with that hip and knee flexed. The examiner hyperextends the hip with a downward force on the knee. A positive test reproduces the patient’s pain and is suggestive of sacroiliac joint dysfunction or facet dysfunction.
Facet Loading: The examiner passively extends and laterally rotates the patient’s lumbar spine in a seated or standing position. A positive test is reproduction of the reported pain, not beyond the knees, and suggestive of ipsilateral lumbar spondylosis.
This segment is intended to give generalists some improved tools in assessing the significance of complaints. It is not a comprehensive tool.
History: how did the pain begin? When did it begin? Is it getting better or worse? Any bowel or bladder control issues? Are the symptoms worse in the lower limbs or in the back? Are symptoms worse overnight (especially with a history of cancer)?
Did it start with minor trauma and is it now getting better?
If symptoms are primarily in the back, not at night more than the daytime, and don't involve lower limbs more than the back, and improving, this favors less serious mechanical musculoskeletal etiologies. It also probably does not warrant radiographic/imaging studies. Night more than day symptoms, though not pathognomonic, should raise suspicion for tumor etiology.
Major trauma such as a fall from height, especially with external evidence of trauma, and not improved over several days should raise suspicion of a fracture and will likely warrant at least plain radiographs.
Imaging by CT or MRI should frequently be reserved for suspected tumor etiology or with more specific evidence of lumbosacral root or other pathology, based on history and exam findings.
Be aware there are ample studies over decades documenting that more than 25% of asymptomatic adult patients have "significant imaging abnormalities" on spine imaging. CT and MRI imaging should not be a "screening" tool. Reserve it for suspicious cases after history and exam point to a need for further elucidation.
Generally in most frank radiculopathies from HNP, symptoms are greater in the lower limbs, with pain and sensory symptoms in a dermatomal distribution and weakness in a myotomal pattern corresponding to the root level of the dermatomal abnormality. ; usually unilateral S1, L5, L4, less frequently at other levels above or below those.
Occasionally a central disc protrusion, fracture, or other lesion can be midline affecting more than one sacral nerve root bilaterally and possibly associated with saddle anesthesia and bowel and bladder control issues. This is a relative emergency.
The term "radicular" specifically refers to nerve root involvement. Radicular pain usually radiates; but not all radiating pain is radicular. There are multiple non-nerve root musculoskeletal etiologies that radiate pain to buttocks, groin, scrotum, labia, thigh and even below the knee, but rarely to the foot.
Once history is obtained, a relatively simple exam can be done to narrow the diagnostic possibilities and identify more serious etiologies.
Exam:This exam should take only a few minutes.
The back should be inspected for obvious trauma or deformity.
Percussion over lower thoracic, lumbar and sacral spinous processes, if very localized, maybe a cause for further radiographic evaluation.
Carefully and firmly palpate for asymmetrical tenderness over the posterior iliac crests, posterior superior iliac spine, and SI ligaments. If pain is below the back, into the thighs, palpate over the greater trochanters as well.
Asymmetric tenderness in these areas suggest less serious musculoskeletal etiologies.
Check patellar (L3-4 primarily) and Achilles (primarily S-1) reflexes for symmetry.
With the patient seated on the exam table passively extend the knee. Hamstring discomfort or tightness are common and usually not an indication of nerve root pathology. Radiation of severe pain and possibly paresthesias to the posterior thigh or below the knee is likely indicative of nerve root pathology.
Still with the patient seated, check strength of ankle dorsiflexion(L-4), and great toe extensors(L-5). If Achilles reflex is unilaterally decreased, check ankle plantar flexing strength by having the patient face the exam table, touch the table for balance, and attempt to do unilateral toe raises for several repetitions on each side. This is a better way to check for plantar flexion strength since attempting to do that manual is not usually revealing because even fairly weak ankle PF is difficult to overcome by manual force.
Percussion for kidney area tenderness can be helpful in certain presentations of back pain due to kidney involvement.
Palpation of the abdomen may reveal an abdominal aortic aneurysm or other mass as a cause for the low back pain. Rarely, palpable abdominal masses may be the cause for lumbosacral plexus compression mimicking radiculopathy.