Schmorl’s nodes are usually an incidental finding whereby a disc herniates into the vertebral body. The clinical course is rarely symptomatic. Here we present a 41-year-old man who, following chiropractic manipulation, developed an acute Schmorl’s node. The patient was successfully managed with conservative measures. 41-year-old man with acute or chronic low back pain following a chiropractic adjustment. Imaging demonstrated the development of an acute lumbar four-five disc Schmorl’s node in lumbar vertebral body 4 after a chiropractic adjustment. He was treated with conservative measures with over 85% back pain relief. Acute Schmorl’s nodes can develop after chiropractic adjustment. In the case presented, conservative measures resulted in an 85% improvement in pain.
Schmorl’s nodes are intervertebral discs that have herniated into the vertebral body. Schmorl’s lymph nodes are asymptomatic and usually an incidental finding with an incidence as high as 76% and a slightly higher prevalence in men [1,2]. They are most often located in the thoracolumbar spine [1,3-5]. It is possible to see the bony deformity on a CT scan, but due to its asymptomatic nature, MRI is usually not performed. In a minority of patients, Schmorl’s nodes may cause pain, in which case MRI may be useful to assess treatment options. Here we present a patient with an acute exacerbation of low back pain due to the development of a Schmorl’s node following a chiropractic adjustment.
Presentation of the case
A 41-year-old man with a five-year history of anterior and posterior L5-S1 instrumented fusions presented to the clinic with low back pain. The patient reported that fourteen weeks prior to the clinic visit, he suffered a mechanical fall to floor level, resulting in low back pain. Due to the persistent nature of the pain, her primary care physician ordered a vertical lumbar X-ray six weeks later, which revealed no fractures, as shown in the figure 1. Continued lingering pain prompted reordering of a non-contrast CT lumbar spine, demonstrating no fractures, as shown in the figure 2.
The patient then went to a chiropractor, who tried to “crack” his back. When manipulated, the patient noted an immediate exacerbation of pain with a change in the character of the pain. The pain has progressed to involve more than the midline now, including the right flank and posterior lower right leg. The majority of the pain was described as a muscle spasm in the right flank area. He attempted to numb the pain with his current regimen of painkillers, but this proved ineffective and began to affect his ability to move around and perform usual activities of daily living (ADLs), such as changing his own clothes, etc. an MRI of the lumbar spine, shown in Figure 3. The MRI results prompted a referral to a neurosurgery clinic.
The patient presented to the neurosurgery clinic in a seated walker because the upright posture exacerbated the pain. Pain was rated as 5 out of 10 at baseline, increasing to 10 out of 10 with all movements involving the lower back or upright position. Hydrocodone, carisoprodol, acetaminophen, and pregabalin provided minimal relief, reducing pain from 10 out of 10 to 7 out of 10. Patient denied loss of bowel or bladder control and numbness of the genitals or rectum. He denied recent fevers, diabetes, immunosuppressive medications or intravenous drug use.
On physical examination, the patient demonstrated no loss of sensation or proprioception. Muscle examination revealed bilateral analgesic movements of the lower limbs, worse in the left lower limb, causing right lumbar pain on exertion. It was not tender to palpation of the lumbar medial spine or the bilateral paraspinal muscles. There was no low back erythema or edema noted. The body mass index was calculated at 33.
Patient was prescribed a lumbar support brace, continued oral medications with a referral to pain management to consider invasive therapies, such as trigger point/epidural (TSI) steroid injections , then follow up with physical therapy (PT). In follow-up phone conversations with the patient, he underwent a series of ISEs, which after one week significantly improved his symptoms and, after one month with additional mild TP, improved approximately 85% of his symptoms. The patient continues with conservative treatment at this time.
In a minority of patients, Schmorl’s nodes can cause pain. A review of the literature reveals that the suspected mechanisms of action in the painful development of Schmorl’s node are mainly axial loads or rotational injuries such as riding, being struck by a motor vehicle, l monofin training and paddle. [1,2,4,5]. This is the first reported case of chiropractic manipulation presumed to be the cause, as imaging before and after the manipulation clearly demonstrates the development of Schmorl’s node at the lumbar space four-five discs herniating in the lumbar vertebral body at four. Despite the literature’s emphasis on traumatic events as precursors, the majority of Schmorl’s nodes are non-traumatic and asymptomatic with imaging features of chronic injury. [2,6].
The absence of symptoms may be due to the slow and indolent nature of the suspected etiologies. In one pattern, aging degenerates the cartilaginous endplate through which the nucleus pulposus can penetrate if increased intradiscal pressure overcomes the weakened endplate as opposed to the annulus fibrosus [1,7]. Mechanisms inherent in the nucleus pulposus may trigger cytokines and an inflammatory response resulting in pain or other symptoms . Other theories for pain generation include endplate fracture through which the nucleus pulposus herniates and activates nociceptors in the annulus fibrosus and periosteum of the vertebral bodies which are exacerbated by micromovements, swelling and inflammation. [8,9].
Imaging findings of increased edema in all four lumbar vertebral bodies support these proposed mechanisms of pain generation from acute Schmorl’s node formation. MRI is the most specific and sensitive for diagnosing Schmorl’s node as a cause of pain . If inflammation and edema are local pain generators, then their presence as increased intensity on T2 and hyperintense short tau inversion recovery (STIR) signal surrounding the acutely formed Schmorl’s node, as seen on the MRI of this patient, supports this hypothesis in the absence of any other pathology. [5-7]. Hyperintense STIR and increased T2 signal are not unique to Schmorl’s ganglia; therefore, other pathologies should also be excluded, such as infection, tumor, or abnormal vasculature.
When the diagnosis of acute Schmorl’s node is reached after proper workup, treatment ensues. Treatment is usually conservative, including anti-inflammatories, rest, physical therapy, bracing, or injections, including blocks. Symptoms usually resolve with conservative management, but can last from two weeks to six months [1-3,5,7]. However, the pain may be severe enough to impact ADLs and quality of life, as described in this case. In cases where patients fail conservative management, surgical interventions such as vertebroplasty or discectomy with segmental fusion have been pursued [1,3,7-9].
Schmorl’s lymph nodes are usually benign incidental findings. However, under certain circumstances, they can cause severe pain and, in rare cases, lead to surgery. The causes of acute Schmorl’s nodes vary, but have been associated with local trauma to this area of the spine. This report is the first documented case of an acute Schmorl’s node following a local traumatic chiropractic adjustment.