4.1 Introduction

It is known that the majority of spine pain is benign and will improve fairly rapidly. For this reason, most guidelines on the treatment of back pain generally recommend avoiding advanced imaging to reduce unnecessary expenditures and patient exposure to ionizing radiation. However, certain conditions justify more rapid utilization of advanced imaging and early treatment. The most prevalent of these conditions is compression fractures of the spine. These fractures occur when the bone is not of sufficient strength to handle the axial load applied to the vertebral body. The most common causes of loss of vertebral strength are osteoporosis and neoplasms involving the spine. Other conditions including infection of the vertebrae and high-velocity trauma can also predispose to vertebral fractures by weakening the vertebral body or by overwhelming the vertebral strength by force, respectively.

The incidence of VCFs has been rising over the last few decades, due to the rising age of our population. Many VCFs are asymptomatic and heal only to be identified incidentally on imaging studies. However, many of these fractures can cause severe pain and often become chronically painful, leading to substantial disability. ¹ In addition, the presence of multiple fractures, occurring over the course of months or years, may lead to hyperkyphosis with secondary decrease in pulmonary function, abdominal distention with early satiety leading to malnutrition, as well as increased mortality. ^{2 – 5} For these reasons, diagnosis of VCFs, along with appropriate management, can improve health outcomes.

4.2 Presentation of Vertebral Compression Fractures

Compression fractures of the thoracolumbar spine typically result from a flexion-type injury. This results in a fracture of the anterior column (involving the anterior vertebral body and anterior longitudinal ligament), most commonly with a wedge-type appearance (▶Fig. 4.1). The primary symptom of a compression fracture is pain in the area of the fracture and pain with movement or transition from one position to another. Neurologic deficits are very unusual in patients with osteoporotic VCFs. The transitional pain usually manifests itself when patients go from a sitting to standing position or from a lying to sitting position and VCF-related pain also often causes difficulty with standing and walking. ⁶

As mentioned earlier, these fractures occur when the compressive strength of the vertebral body is insufficient to tolerate the axial load applied to the vertebral body. In patients with osteoporosis or severe osteoporosis, even minor trauma such as a vigorous cough or sneeze, or even turning over in bed can cause a fracture. In fact, it has been reported that approximately 30% of vertebral fractures in severely osteoporotic patients occur when the patient is in bed. ^{7 , 8} It has been hypothesized that the load in these cases results from paraspinal muscle contraction. ^{9 – 11} In patients with only moderate weakening of the vertebral body usually from osteoporosis, fractures typically occur with activities such as lifting, pulling, stepping down from an elevated height, or falling. In the absence of osteoporosis, a severe axial load is typically required for fracture, typically as a result of a motor vehicle collision or a fall from substantial height. When compression fractures occur in patients younger than 55 years, or in an isolated vertebral body where fractures are uncommon (L5 or above T5), neoplastic involvement must be ruled out. ¹²

VCFs are not always painful and are commonly detected only incidentally on imaging for other reasons. On occasion, multiple compression fractures can result in a kyphotic deformity, which impacts the sagittal balance of the patient, causing them to fall outside of the cone of economy (▶Fig. 4.2). ¹³ When this occurs, patients experience fatigue and pain resulting from biomechanical stresses and paraspinal spasm as a result of the increased work required to maintain an erect posture. ¹⁴