Keywords
osteoarthritis - lumbar vertebrae - thoracic vertebrae
Introduction
Back pain is a prevalent condition that is responsible for extensive direct and indirect
costs as a result of healthcare systems utilization and absenteeism. Its etiological
clarification can be imposed as a true diagnostic challenge given its proximity to
vital organs and the phenomenon of referred pain that results from the neuronal convergence
of visceral and somatic afferent fibers at the level of the dorsal spine.[1]
[2] This explains the broad spectrum of differential diagnoses of back pain, including
disc herniation, vertebral fracture, facet degenerative changes, intercostal neuralgia,
rib fractures, and non-orthopedic forum pathologies, namely cardiac, spinal, pulmonary
and abdominal.[3]
Although osteoarthrosis (OA) of the costovertebral joint is a common degenerative
finding in geriatric patients,[4] its isolated occurrence in young patients is rare, with it being poorly recognized
in the genesis of dorsal pain.[5] The authors present the case of a young patient with dorsal pain, irradiated to
the left hemithorax, originating from OA of a costovertebral joint. This case highlights
the complexity of the diagnosis of dorsal pain and aims to sensitize physicians to
the existence of this diagnosis in order to avoid costly and often unnecessary negative
visceral workups.
Case Description
A 40-year-old male patient reported chest pain with 4 weeks of evolution, of insidious
appearance, irradiated to the left thorax. The pain motivated two visits to the emergency
department, where the patient was evaluated by an internal medicine specialist and
underwent electrocardiogram, chest X-ray, echocardiogram, abdominal ultrasonography,
and analytical study (blood count, sedimentation speed and C-reactive protein). All
tests were negative for cardiac, pulmonary, or abdominal pathology, and the patient’s
pain was interpreted as a lower trapezius muscle contracture. He was prescribed muscle
relaxants, physiotherapy and subsequently referred for evaluation at our institution.
The symptoms became progressively disabling with excruciating pain during trunk torsional
movements, deep inspiration, or coughing, significantly limiting activities of daily
living and sleep quality. The patient denied any history of trauma, fever, fatigue,
or weight loss. He reported previous episodes of pain, similar to the current one,
but of lower intensity and self-limited, susceptible to symptomatic relief with the
use of antiinflammatory drugs. On objective examination, there were no asymmetries
or thoracic masses. Palpation of thoracic spinous apophyses, interspinous ligament,
and costotransverse junction was painless; however, compression of the left lower
ribs triggered paravertebral pain. Neurological examination was normal.
Magnetic resonance imaging of the dorsal column revealed hyposignal in T1-weighted
sequences and hypersignal in T2-weighted sequences at the level of the left D10 costovertebral
joint. Intervertebral disc pathology was excluded. Due to the uncertain nature of
the lesion, dorsal computed tomography (CT) scan and bone scintigraphy were requested.
The CT revealed the presence of degenerative alterations of the D10 costovertebral
joint ([Figure 1]) in agreement with a focal increase in the uptake of technetium-99m (Tc-99m) in
the same location ([Figure 2]), and the results were in favor of the diagnosis of costovertebral OA. The dosing
of inflammatory markers (sedimentation rate and C-reactive protein), rheumatological
markers (rheumatology factor, antinuclear antibody, anti-dsDNA antibodies), HLA-B27,
viral markers, and blood cultures were all negative. Intralesional injection of CT-guided
corticosteroids was proposed for diagnosis and therapy. The left D10 costovertebral
joint was first properly identified by local injection of 1 mL of lidocaine (20 mg/mL),
which resulted in immediate pain relief. The positive response to the local anesthetic
allowed us not only to confirm the location of the lesion, but also to confirm the
diagnosis. Subsequently, 2 mL of methylprednisolone (40 mg/mL) was administered locally
of dorsal back pain remain poorly represented in the literature.
Fig. 1 Computed tomography. Axial (left) and coronal (right) cuts. The 10th left costovertebral
joint presents significant degenerative changes, with sclerosis at the levels of the
vertebral body, pedicle, and rib head.
Fig. 2 Bone scintigraphy marked with Tc-99m. Isolated hyperuptake at the level of the 10th
left costovertebral joint (L- left side; R-right side).
Progressive pain relief was observed over the following days, with complete resolution
at 3 weeks after corticosteroid injection. Pain recurrence has not been observed in
the last 2 years.
Discussion
The role of costovertebral OA in the genesis of dorsal back pain remain poorly represented
in the literature. The high prevalence of costovertebral degenerative changes in asymptomatic
patients requires a careful interpretation of imaging findings, and a clinical-imaging
correlation is essential. Although these are quite common in geriatric age,[4] their occurrence in young patients without rheumatic diseases is rare. Clinically,
they have an extremely variable spectrum and may be asymptomatic or have a highly
debilitating presentation, with patients reporting posterior chest pain, which may
radiate to the chest or be felt along the respective rib.[3] Pain may be exacerbated by provocative maneuvers, including deep inspiration, cough,
chest flexion or rotation, and compression of the corresponding rib.
The most relevant publication on this is by Sales et al.,[5] who presented a series of five cases of isolated costovertebral OA (mean age of
40.6 years) treated favorably by performing a rib resection arthroplasty.
The diagnostic validity of bone scintigraphy under degenerative conditions remains
questionable.[6] Verdoorn et al.[7] evaluated the correlation between increased Tc-99m uptake in the costovertebral
joints, the presence of local pain and favorable response to percutaneous injection
of anesthetic and corticosteroids. The authors found that more than half of the cases
with Tc-99m hyperuptake were asymptomatic, and there was no correlation between the
presence of pain and the predictability of response to percutaneous injection treatment.
These results are justified by the possibility of confusing painful points and the
presence of more than one increased tc-99m uptake area, which reduces the diagnostic
efficacy and predictability of favorable response to treatment with percutaneous corticosteroid
injection.
In our patient, it was possible to obtain a complete relief of symptoms with corticosteroid
injection; however, according to the results reported by Sales et al.,[5] a recurrence of symptoms in the medium/long term can be expected, and resection
arthroplasty can be considered in order to obtain lasting results.
