Biomechanical disorders are the most common cause of neck pain and can be caused by the degeneration that accompanies aging (degenerative arthritis), inflammatory diseases (rheumatoid arthritis), or trauma. This pain can also provide early warning of spinal cord compression (an emergency situation), a primary or secondary tumor, or (rarely) infection.
Additional and sometimes multiple therapies may become necessary to treat chronic or radicular neck pain. As always with painful conditions, treatment begins with diagnosis and the most conservative appropriate therapies and proceeds, when indicated, to interventional therapies. Other treatments include psychological techniques (cognitive therapy), manipulative techniques, pharmaceuticals, acupuncture, massage, cervical epidural blocks (C2 ganglion, trigeminal ganglion, sphenopalatine), neuroablation (botulinum injections, radiofrequency), neuromodulation (greater occipital nerve stimulation, supraorbital nerve stimulation, gasserian ganglion stimulation), intrathecal infusion, and surgical techniques (fusion, diskectomy). In cases of systemic illnesses or spinal compression, pain and the underlying cause must be treated aggressively to prevent development of complications.
Degenerative arthritis can reduce surface cartilage in the cervical spine and/or produce bone spurs that can entangle a nerve or put pressure on a nerve root. Degenerative disk disease occurs because aging disks lose their flexibility, and the results are locally painful tears in the annulus fibrosis or herniated disks that press on nerve roots. Depending on their manifestation, degree, and location, degenerative arthritis and degenerative disk disease can be benign or can cause radiculopathy, pain that is referred to the shoulder and arm on the affected side(s) and produces a tingling sensation in fingers, hand(s), or arm(s). In severe cases, called myelopathy, degenerative disk disease can cause spinal stenosis that is sometimes manifested as weakness or difficulty with walking or coordination.
Many patients with radiculopathy or pronounced myelopathy, however, will have a positive outcome after a surgical intervention, even in those with severe myelopathy, but especially those whose symptoms are recalcitrant through 6 weeks of management or are progressive. Cervical foraminotomy/diskectomy increases space where the nerve root exits the spinal canal by removing part of the joint that covers the nerve root and a portion of the disk, if necessary. Anterior cervical diskectomy, in which a surgeon gains access to the cervical spine through the front of the neck, is used when it is necessary to remove one or more intervertebral disks or bone spurs that are causing nerve damage. Some surgeons fill the resulting intervertebral space with a bone graft. In the presence of axial neck pain or any segmental kyphosis, fusion is also performed. In patients with posterolateral or lateral soft disk herniations, with focal osteophyte infringement, or in large patients with short necks and caudal lesions, a posterior laminoforaminotomy is often performed.
Conservative treatment can include acupuncture and massage. In one prospective, randomized, controlled trial comparing these therapies after five treatments over 3 weeks, 56 patients received acupuncture, 60 massage, and 61 sham laser acupuncture. Compared with the massage group but not the sham group, motion-related pain significantly improved in the acupuncture group, which also had best results for all secondary outcomes. These investigators believed their results point to the short-term efficacy of acupuncture and called for studies of its long-term efficacy.
A panel charged with developing evidence-based clinical practice guidelines for rehabilitation methods for neck pain identified therapeutic exercises as the only intervention offering clinically important benefits and noted that evidence is lacking for the efficacy of thermotherapy, therapeutic ultrasound, massage, and electrical stimulation.
Investigators have also sought to determine the efficacy of injecting botulinum toxin A into chronically painful neck muscles. One study compared the efficacy of a single injection of high-dose botulinum toxin A vs a saline injection and found that each group of patients improved significantly in terms of pain, disability, and tolerance to trigger point pressure. The incidence of adverse events with the botulinum injections was “large,” and the investigators concluded that this was not an effective single therapy.
Anterior cervical diskectomy and fusion may also be performed to treat chronic neck pain without radiculopathy or myelopathy. One 53-month follow-up study involved 38 patients who had painful disk(s) proven by diskography. After the procedure, patients reported a significant decrease in pain and significant increase in function, and 30 patients were satisfied with their outcomes.
Another study to assess the clinical outcome for anterior cervical diskectomy and fusion patients at an average follow-up of 4.4 years found that 82% of the 87 patients were satisfied with their outcome, and 93% reported improvement in pain.
Rheumatoid arthritis can cause serious problems in the relationship between C1 (the atlas vertebrae) and C2 (the axis vertebrae), including instability or a partial dislocation (atlantoaxial subluxation). When subluxation exceeds 9 mm, cord compression is likely. Rheumatoid arthritis can also cause deterioration of the joints between the base of the skull and C1–C2 to such an extent that the odontoid migrates upward and places pressure on the brain stem (basilar invagination). This can cause sudden death and may present as an untoward amount of flexion, posterior skull pain, tingling, and numbness in the fourth and fifth finger, in the medial forearm, or with neck movement.
The KIM-STIM, an electrical stimulator that is molded to the patient’s ear, fitted with multiple electrodes, and managed by the patient, is being used to treat pain associated with atlantoaxial subluxation syndrome as well as head, neck, and shoulder pain.
Posterior fusion of C1-C2 is indicated for atlantoaxial subluxation when patients have neurologic abnormality, intractable pain, or vertebral artery or cord compression demonstrated on MRI. The recommended treatment for basilar invagination is neurosurgery when MRI confirms cord compression. Otherwise, patients may benefit from conservative pharmaceutical and stretching approaches (neck traction).
Degeneration can also lead to two types of narrowing or stenosis in the cervical spine: (1) cervical spondylolysis, which occurs when the pars articulars is damaged and cannot continue to separate vertebrae, which may cause neck pain as well as arm weakness; and (2) the narrowing of the spinal canal and foramina, which occurs when the facets become inflamed from undue pressure and results in compression of the spinal cord, neuropathic symptoms, and neuropathic pain.
Spinal stenosis is treated by decompressing the spinal cord, the nerve roots, or both, and replacing a section of the vertebra and adjacent intervertebral disks with a bone graft or metal plate (cervical corpectomy). When patients have four or more levels of stenosis, the preferred method is laminoplasty.
A review was conducted of the outcome of anterior cervical corpectomy, reconstruction with allograft fibula, and placement of an anterior plate in 261 patients with spinal stenosis due to spondylosis (197 patients), postlaminectomy kyphosis (27 patients), acute fracture (25 patients), or ossification of the posterior longitudinal ligament (12 patients). Nearly half of the procedures involved two disk levels and one vertebral body; 96 involved two levels, 31 three levels, and 1 four levels. The mean follow-up was 25.7 months. The fusion was successful in 226 patients, 33 developed an asymptomatic stable or fibrous union, and 2 developed unstable pseudoarthrosis requiring reoperation. Two patients had transient unilateral upper extremity weakness, 35 developed transient dysphagia, 7 permanent dysphagia, 35 transient hoarseness, and 2 permanent hoarseness. The hardware failed in 14 patients. These investigators concluded that this procedure is effective and improves symptoms in nearly all patients.
Whiplash often leads to chronic pain in the cervical zygapophyseal joints. Treatment ranges from conservative measures to neuroablation.
Bogduk et al. have published widely on this condition and maintain that the evidence for efficacy of conservative measures is poor. Another group reviewed the literature to determine the efficacy of various exercise methods and concluded that moderate evidence supports early treatment with mobilizing exercise to treat acute whiplash, but no evidence supports the effectiveness of group exercise, “neck schools,” or single sessions of extension-retraction exercises.
Clinicians have also investigated the merits of injecting various agents. One double-blind study, for example, compared the efficacy of an intraarticular injection of 0.5% bupivacaine (n = 20) or 5.7 mg of betamethasone (n = 21). The end point was time needed to return to 50% of preinjection pain. In each group, fewer than 50% of patients had pain relief from more than a week and fewer than 20 had relief for a month, indicating that the corticosteroid injection was not effective. Another randomized, controlled trial compared five trigger-point injections of botulinum toxin A in 14 patients and with saline in 12 and found that range of neck motion and subjective pain improved significantly in the treatment group compared with control subjects but the treatment only led to a trend toward improved functioning.
To help establish the efficacy of percutaneous radiofrequency neurotomy for the treatment of cervical zygapophyseal joint pain, Lord et al. conducted a randomized, double-blind trial, comparing percutaneous radiofrequency neurotomy involving multiple lesions using an 80°C electrode in 12 patients with a sham identical control treatment in 12 similar patients. The pain generator had been confirmed by double-blind, placebo-controlled nerve blocks using a local anesthetic. The active treatment group had a median time until pain returned to 50% of pretreatment level of 263 days vs 8 days in the control group. One control patient and 7 treatment patients were pain free at 27 weeks. These investigators concluded that multiple radiofrequency lesioning of target nerves is efficacious.
The same group reported on the use of radiofrequency neurotomy in 28 patients in whom diagnostic blocks confirmed cervical zygapophyseal pain. An initial procedure led to complete pain relief in 71% of patients. Those who failed the initial procedure did not benefit from a repeat procedure, but pain return after a beneficial initial procedure was successfully treated with a repeat neurotomy.