Spinal anatomy for spine pain
To understand the spine pain well we need a brief knowledge about the spine anatomy. Spine is composed of 33 vertebrae. Among them, 7 vertebrae lie in cervical region. These vertebrae have an arrangement of backward bending. They, specially the first cervical vertebra atlas, bear the weight of head. The thoracic vertebrae, also known as dorsal column, are 12 in number. They form the major length of spine. Their arrangement is forward bending. They do not bear but transmit the weight to lumbar spine. There are 5 lumbar vertebrae, which are arranged in backward bending. They bear most of body weight. In between two vertebral bodies there lie a semi fluid cartilage material called inter vertebral disc. This act as shock absorber but sometimes it’s deviation from anatomical space causes major problem. The 5 sacral vertebrae are fused and forward curved. The coccyx is fusion of vertebrae.
To make our posture energy efficient, cervical and lumbar vertebra are bend backwards and to balance it thoracic vertebra are bent forwards. The spinal canal is formed behind the articulated vertebral body by the posterior elements of the vertebral column. Spinal canal can be divided into a central portion and two lateral portions. The central portion is occupied by the spinal cord. The lateral portion contains the nerve roots. There are eight cervical spinal nerve roots, twelve thoracic spinal nerve roots, five lumbar spinal nerve roots, five sacral spinal nerve roots and one coccygeal spinal nerve roots. Anterior and posterior roots join to form spinal nerves. Degenerative changes in these structures may lead to irritation or compression to nerves or nerve roots and pain ensues.
spine pain causes
Deviation from above normal structures may cause spine pain. Some systemic causes are also included. When these causes affect cervical spine they emerge as causes of neck pain, when affect lumbar spine they are then causes of lower back pain. Thoracic spinal pain occurs rarely. Some causes are listed below:
- Trauma to the spine
- Developmental abnormalities
- Spinal deformity
- Idiopathic scoliosis
- Neuromuscular scoliosis
- Congenital scoliosis
- Scheuermann’s kyphosis
- Inflammatory diseases: like Ankylosing spondylitis
- Infections of spine: Pyogenic, tubercular infections, epidural abscess
- Primary spine tumor
- Intradural tumor
- Metastatic bone tumor of spine
- Discogenic low back pain
- Spinal stenosis
- Lumbar disc hernia
- Cauda equina syndrome
- Thoracic disc hernia (rare)
- Cervical myelopathy
- Cervical radiculopathy
- Metabolic bone disease affecting the spine like Osteoporosis
- Causes of referred spinal pain:
- Respiratory cause, e.g.mesothelioma
- Vascular cause, e.g. abdominal aortic aneurysm
- Renal cause, e.g. pyelonephritis
- Gastrointestinal cause, e.g. peptic ulcer and pancreatitis
- Urinary and genital cause, e.g. testicular, ovarian or prostatic carcinoma
Spine pain management
To manage a patient of spine pain we must take a detailed history, do clinical examinations and investigations depending on the condition of the patient.
History taking (symptoms of spine pain)
A detailed history of the pain including site, type, severity, duration, frequency and aggravating factors should be sought. Has there been any history of trauma? Is the pain present at night? Is there associated pain in the upper limbs (brachalgia) or lower limbs (sciatica)? Is there associated numbness, tingling, weakness, or difficulty with gait? Is there a family history of ankylosing spondylitis or rheumatoid arthritis? Are there concurrent medical conditions such as diabetes, peripheral vascular diseases, osteoarthritis of the hip or previous malignancies? Are there systemic symptoms such as unexplained weight loss, chills or fever?
Commonly accepted danger signs that show us reason to suspect serious pathology of the spine (such as fractures, tumours, infection or cauda equina syndrome) are listed below:
- Age <20 years or >50 years
- Recent significant trauma
- History of malignant disease
- Unexplained weight loss
- Constitutional symptoms (fever, chills)
- Immune suppression (intravenous drug abuse, prolonged corticosteroid use)
- Progressive or severe sensory alteration or motor weakness
- Acute difficulty of urination (painless retention)
- Numbness in perineum or buttocks and/or stool incontinence
Pain may be arising from the spine, but non-spinal causes of pain must also be considered. Patients should always be asked about the presence of numbness of saddle area and/or difficulties passing urine or stool, as these symptoms may indicate a cauda equina syndrome. Patients should be asked whether the pain is interfering with their ability to work. What treatment has the patient already tried and how effective were these treatments, e.g. analgesics, exercise, physiotherapy or spinal injections? Pending litigation or workers’ compensation claims may have a negative prognostic effect on future treatments and therefore should be enquired about.
Spinal deformities, e.g. scoliosis and kyphosis are generally painless in children, but may become symptomatic in adult life. How quickly has the spinal deformity progressed? It is important to assess skeletal maturity and whether the child has gone through a recent growth spurt? Has menstruation commenced in the female or has the voice dropped in the male?
Examinations for spine pain
The patient should be undressed and posture should be evaluated in both the frontal and sagittal plane. Shoulder or waist asymmetry suggests the presence of scoliosis. The Adams’ forward bend test will accentuate trunk asymmetry and allow appreciation of rib or loin prominence on the convex side of the curve. The skin should be examined for cutaneous neurofibromata, café-au-lait patches or axillary freckles commonly present in neurofibromatosis. Neurological examination should include abdominal reflexes. Palpation is useful to locate specific areas of tenderness. Ranges of motion should be assessed. The normal range of motion in the cervical spine is 45° of flexion, 55° of extension, 70° of rotation and 40° lateral bend. The normal range of motion in the lumbar spine is 40–60° of flexion, 20–35°of extension, 15–20°lateral bending and 3–18°of rotation. Schober’s test is a simple clinical test to evaluate spinal mobility.
Neurological examination of the upper and lower limbs will focus on tone, power, coordination, reflexes, sensation and gait. A rectal examination should be performed if there is any concern about cauda equina integrity. Myelopathy or upper motor neurone (UMN) lesions are suggested by spastic muscle, motor weakness, hyper-reflexia, a positive Hoffmann’s sign (if the middle finger is flicked into extension, the thumb and other fingers flex briskly), up-going Babinski response, patellar and ankle clonuses. Typical signs of radiculopathy (lower motor neuron (LMN) lesion) include sensory loss, motor weakness, flaccid paralysis, muscle atrophy, loss of reflexes and muscle fasciculation.
The straight leg raise test is performed with the patient in the supine position. The leg is elevated with the knee straight to increase tension along the L5 and S1 nerve roots. The test is positive if the leg elevation provokes radicular pain. Lasègue’s sign denotes radicular pain aggravated by ankle dorsiflexion. The femoral stretch test is performed with the patient in the prone position by extending the hip and flexing the knee. This creates tension on the L2, L3 and L4 nerve roots. The femoral nerve stretch test is considered positive if radicular pain occurs in the anterior thigh region during the test.
The examination should include, where appropriate, examination of the shoulder, hip, knee, sacroiliac joint and vascular system, as dual pathology is common in the ageing community.
Investigations for spine pain
- Plain radiographs
- Magnetic resonance imaging
- Computed tomography
- Bone scintigraphy
- Bone densitometry
- Provocative discography
- Facet joint injections
- Foraminal epidural steroid injections
- Spinal biopsy
Spinal pain treatment
- Reassure patients (favourable prognosis)
- Advise patients to stay active
- Prescribe medication if necessary (preferably at fixed time intervals)
- Consider opioids, muscle relaxants
- Discourage bed rest
- Consider spinal manipulation, exercises and support of spine for pain relief.
- In cases like metabolic diseases, tumors, developmental deformity etc specific measures including surgery may be needed.