Spinal Pain: Acute & Chronic Management

Spinal pain is common, with a prevalence in the US as high as 70% to 80%, and lower back pain is the greatest source of disability in the US. When no structural deficits are found on initial imaging, treatment of spinal pain is conservative, consisting of anti-inflammatories and analgesia to make physical therapy and other conservative treatments more easily accomplished. This continues throughout the subacute period of 2 weeks to 3 months, after which time pain is considered chronic and interventional treatments may be warranted. This review covers acute and chronic treatment for some frequently experienced causes of spinal pain.

Key Points of Whiplash Type Injury

Diagnosis

Sandra was diagnosed with whiplash-associated disorder (WAD) and facet-mediated pain.

Discussion

WAD is common, with 300 to 600 cases per 100,000 individuals in North America and Western Europe.¹ Motor vehicle accidents are the most common cause. In the case presented, the inciting event helps explain the etiology of Sandra’s pain presentation. WAD is characterized by sudden acceleration-deceleration head movements with neck flexion and then extension resulting in injury.² In WAD grades 1 through 3, if injury occurred within the last 2 weeks, a soft collar, rest, and leave from work may not improve patient outcomes.¹ In the subacute period (2 weeks-3 months), a multimodal approach to treatment including supine relaxation training, counseling to reduce anxiety, manual massage, mobilization of the cervical spine, and active exercises to reduce cervical lordosis can help improve overall outcomes compared with passive treatment.³ Oral corticosteroids such as methylprednisolone can be used, but the benefits of such medications is not entirely clear.³

It is imperative to make sure there are no structural impairments that might explain persistent pain (eg, tearing of the ligamentum flavum, anulus disruption, facet joint fractures, articular pillar fractures, endplate avulsion/fractures, or vertebral body fractures).¹ Although additional imaging is not required for facet joint interventions, if there is concern about any new neurologic deficit, more detailed imaging of the cervical spine may be warranted. Recovery from whiplash injury can vary. Some recover quickly, whereas others may experience ongoing pain and disability that leads to chronic pain.⁴

For persistent occipital headaches with neck pain in the setting of WAD, diagnostic third occipital nerve blocks at the C2-C3 zygoapophyseal joint are indicated. Up to 60% of patients can obtain complete pain relief with diagnostic blocks with local anesthetic.² Subsequently, radiofrequency ablation (RFA) can be done for longer term relief lasting several months.

When choosing cervical facet joint blocks versus medial branch blocks, there are a few points to consider. First, facet joint intra-articular therapies can involve the placement of both local anesthetic and corticosteroid. This helps to theoretically achieve a longer lasting analgesic response as both a diagnostic and therapeutic intervention.⁵ In contrast, medial branch blocks are usually only diagnostic and performed with no more than 0.5 mL of local anesthetic only, targeting the medial branch of the dorsal ramus over the waist of the articular pillars of the same numbered vertebra. Typically, if the patient obtains more than 80% relief of their pain for the duration of local anesthetic effect, they may qualify for RFA or rhizotomy of the medial branches, which can provide more than 50% pain reduction for several months.⁶

Key Points of Low Back Pain After Lumbar Spine Surgery

Diagnosis

Steven was diagnosed with SIJ dysfunction bilaterally.

Discussion

SIJ dysfunction can be the primary cause of low back pain in 15% to 40% of cases.⁷ The SIJ is a synovial joint that is stabilized by the sacrotuberous, sacroiliac, and sacrospinous ligaments. The SIJ is supported by the gluteus medius, maximus, erector spinae, latissimus dorsi, biceps femoris, iliacus, psoas, piriformis, oblique and transverse abdominus muscles, and the thoracodorsal fascia.⁷ Innervation is from the L2-S1 ventral rami, lumbosacral plexus, superior gluteal nerve and L4-S4 dorsal rami.⁷ Because of the complex innervation and anatomy of this joint, there are multiple potential pain sources. Several provocative maneuvers are used to help determine if SIJ dysfunction is the pain generator. In general, at least 3 provocative tests (Table) are used to optimize sensitivity and specificity of the musculoskeletal exam to make the diagnosis and help increase the likelihood of a positive response to injection therapy.^8,9

Imaging is not needed or helpful in diagnosing SIJ dysfunction.⁷ If it is suspected, an intra-articular joint injection should provide at least 50% to 75% pain relief for positive diagnosis.⁷ If longer-term relief is desired, other treatments are available, including radiofrequency denervation or ablation targeting the branches of the dorsal rami of L4-S4 for pain from the posterior joint and ligaments.⁷ In some cases, joint fusion can be offered.

In individuals who have had previous lumbar spine surgery, SIJ dysfunction can be a source of pain caused by several factors, including increased mechanical load, iliac crest bone grafting, or misdiagnosis of SIJ syndrome.¹⁰ As with those who have not had previous lumbar spine surgery, treatment is often more conservative initially. NSAIDS, anti-depressants, SIJ belts, and physical therapy are some of the less invasive therapies to consider prior to injections.¹⁰

Key Points of Lumbar Radiculitis

Diagnosis

Maggie was diagnosed with acute lumbar radiculopathy.

Discussion

With an acute lumbar radiculopathy, treatment is more conservative for the first 6 weeks. Most people will improve during this time independent of treatment because disc herniations often regress over time.¹¹ The severe pain experienced can be caused by inflammation of the nerve root and possible irritation of the dorsal root ganglion, leading to pain in a dermatomal pattern.¹² During this period, oral corticosteroids can be prescribed, and have been shown to improve functional status significantly but often do not relieve pain sufficiently.¹³

Once pain is subacute and even chronic in nature, injection therapies may be considered. The most common injections performed are epidural steroid injections, either with particulate or nonparticulate corticosteroids and local anesthetic. Both particulate (eg, triamcinolone, methylprednisolone) and nonparticulate (eg, dexamethasone) corticosteroids can help alleviate radiculitis. There may, however, be longer-lasting relief with the use of particulate steroids.¹⁴ There are certain safety considerations with particulate corticosteroids. For example, inadvertent intra-arterial injection of particulate steroid can result in an embolic effect that may cause neurologic deficits, including paralysis.¹⁴ With regards to interlaminar versus transforaminal approaches for the injection, it is generally recommended that a transforaminal epidural steroid injection can provide short-term (2-4 weeks) pain relief in some patients with a lumbar disc herniation and radiculopathy.¹¹ In general, there is insufficient evidence to support either injection approach over another.¹¹

Summary

Spinal pain often resolves within 2 to 12 weeks of the inciting event. When spinal pain is not resolved with conservative therapy during the subacute period, however, more invasive interventions can be considered. Injection of anesthesia with steroids often provides enough pain relief for individuals to better participate in physical therapy. When this is not the case, more aggressive interventions can be considered.