47 Traction
Types of Distraction
Inhibitory or inhibitive distraction is compression placed over muscles or tendons of insertion, while the joint underneath is stretched.1 An example of this is subcranial distraction. This type of distraction is based on the theory that pressure on the origin or insertion of a muscle fires the Golgi tendon apparatus (GTO) which, as a result, relaxes the muscle. With the muscles relaxed (inhibited), they do not resist the stretch being applied to the underlying joints.
Positional traction by Paris2 is most useful in the spine where two vertebrae are so positioned that the intervertebral foramen between them opens to relieve nerve root pressure. The patient lies over pillows and perhaps is held or assisted by straps.
The three-dimensional mechanical traction table allows positioning of the patient such that the traction force results in a distraction at the spinal level and the side that is desired. The most recent traction tables are designed by Kaltenborn, Paris, and others.2
Therapeutic Effects
When performed correctly, cervical and lumbar traction can cause many effects such as distraction or separation of vertebral bodies; a combination of distraction and gliding of the facet joints; tensing of the ligamentous structures of the spinal segment; widening of the intervertebral foramen; straightening of the spinal curves; and stretching of the spinal musculature.3 Some practitioners believe fluid exchange occurs within the spinal disc during traction.4
It is generally accepted that cervical and lumbar traction can be helpful in centralizing a pain process and in reducing radicular symptoms.5–8 Xin9 suggests that cervical traction helps with vertebrobasilar insufficiency resulting from spondylosis when combined with enhanced external counterpulsation. Others believe more definitive studies are needed to fully understand the benefits of traction.10,11
Sustained or Intermittent Mechanical Traction and Manual Traction
Keep in mind that traction is a force and not a result.1 Results of sustained or intermittent mechanical traction include: (1) foraminal distraction; (2) flattening of any disc bulge; (3) relief of pressure on the nerve root. Conversely, manual traction can be sustained only for a short period of time. The techniques are often much stronger than mechanical traction techniques and the results include stretch to the myofascia; stretch to facet capsules; and occasional repositioning of vertebrae.
Clinical Studies
Katavich,12 indicated in her research, that a stretch generated in cervical muscles and skin during cervical traction has the potential to influence the excitability of motor neurons. She believes manual cervical traction relieves pain and muscle spasm in the neck and upper quartile. In her study, she postulated that afferent input generated by these procedures may lower the excitability of X motor neurons of upper limb muscles. Therefore, an understanding of the receptors and mechanisms underlying manual therapy may allow more effective stimulation, and hence, improved clinical outcomes.
Briem,13 and others, have evaluated the immediate effects of inhibitive distraction on active range of cervical flexion in patients with neck pain. This study did not confirm the immediate effects of inhibitive distraction on cervical flexion AROM, but did provide indications for potential subgroups likely to benefit from this technique. Cai14 described positive predictors for lumbar traction to be noninvolvement of manual work, low-level fear avoidance beliefs, absence of neurologic deficits, and age >30 years. Raney15 described positive predictors for cervical traction to be when the patient reports peripheralization with lower cervical spine (C4-7) mobility testing, positive shoulder abduction test, age ≥55 years, positive upper limb tension test, and positive neck distraction test.
Creighton16 confirmed the merits of positional distraction as a means to open the lumbar neuroforamen. A lateral radiograph was taken of the left lumbar neuroforamen in 10 subjects. The average foraminal opening was >4 mm at L3, L4, and L5. It is possible that even greater opening could have been achieved if towel rolls had been individually fitted—as is done in the clinical setting. Both supine and prone lumbar traction should be attempted to maximize traction benefits.17
Contraindications for Spinal Traction
Traction is known to be a safe procedure with therapeutic value in helping patients with spine-related pain. It is recommended that a detailed history, physical examination, and radiologic studies be performed prior to implementing cervical and lumbar traction techniques. Although the literature is lacking in studies reporting clear contraindications to traction, the clinician must rely on empirical information and opinion. These contraindications include (1) ligamentous instability (prior trauma or rheumatoid arthritic patients); (2) spinal infections, such as osteomyelitis, or discitis; (3) severe osteoporosis or osteopenia; (4) primary bone or spinal cord and metastatic tumors; (5) myelopathies; (6) uncontrolled hypertension or vertebral basilar artery insufficiency (for cervical traction);18 (7) the very young and the very old frail patients; and (8) acute or subacute spinal fractures. Relative contraindications for lumbar traction include pregnancy, abdominal or inguinal hernias, and aortic aneurysms.
Cervical Traction Techniques
Inhibitive Distraction
Subcranial inhibitive distraction is a myofascial technique described by Paris2 that is aimed at releasing tension in suboccipital soft tissue and suboccipital musculature. The patient lies supine with head supported. The physical therapist places the three middle fingers just caudal to the nuchal line, lifts the finger tips upward resting the hands on the treatment table, and then applies a gentle cranial pull, causing a long axis extension. The procedure is performed for 2 to 5 minutes (see Fig. 47-1).
