Spondylogenic back pain may be defined as pain derived from the spinal column and its associated structures. The pain is aggravated by general and specific activities and is relieved, to some extent, by rest.

The pain may be derived from lesions involving the bony components of the spinal column, changes in the sacroiliac joints, or, most commonly, changes occurring in the soft tissues (discs, ligaments, and muscles).

Because these lesions constitute the most common source of low back pain seen in clinical practice, the pathologic changes and the pathogenesis of symptoms are discussed in detail in the chapters that follow.

Tension, irritation, or compression of a lumbar nerve root or roots will usually cause referral of pain symptoms down one or both legs. Although this interference with root function constitutes the most common cause of neurogenic pain, it is prudent to remember there are other causes. Lesions of the central nervous system such as thalamic tumors may present or develop a causalgic type of leg pain, and arachnoid irritation from any cause as well as tumors of the spinal dura may produce back pain. The pathologic lesions most likely to give rise to confusion in diagnosis are neurofibroma, neurilemmoma, ependymoma, and other cysts and tumors involving the nerve roots. These lesions usually occur in the upper lumbar spine outside of the field of view of many computed tomography scans and are missed on sagittal magnetic resonance image scanning if not looked for. The history may be indistinguishable from nerve root pressure due to a disc herniation. Frequently, however, patients report a history of having to get out of bed at night to walk around to obtain relief of their symptoms.

The difficulties that may arise in diagnosis are best exemplified by a patient who presented with severe sciatic pain associated with paresthesia involving the lateral border of the foot and the lateral two toes. His symptoms were aggravated by provocative activity and relieved to some extent by recumbency. Examination revealed an impairment of first sacral root conduction, as evidenced by weakness of the plantar flexors of the ankle, a markedly diminished ankle jerk, and diminution
of appreciation of pinprick over the lateral border of the foot. The patient’s history and clinical findings resembled the classic picture of a herniated lumbosacral disc with first sacral root compression. Myelographic examination was performed and demonstrated a gross defect opposite the body of L2. At surgery, a lipoma involving the first sacral root was found at the point where the root emerged from the conus (Fig. 2-1).

This case emphasizes not only the fact that nerve root tumors can mimic disc herniation but also the importance of looking at the conus region as an essential preoperative investigation in the surgical management of patients apparently suffering from discogenic root compression.

Viscerogenic back pain may be derived from disorders of the kidneys or the pelvic viscera, lesions of the lesser sac, and retroperitoneal tumors (Fig. 2-2). Backache is rarely the sole symptom of visceral disease. Careful questioning will usually elicit description of other symptoms, depending on organ involved. The history of viscerogenic back pain can be differentiated from back pain derived from a disorder of the spinal column by one important feature. The pain is not aggravated by activity, and it is not relieved by rest. Indeed, with severe pain, the patient whose symptoms are visceral in origin will writhe around to get relief, whereas the patient suffering from the tortures of a septic discitis will lie perfectly still.