"Effects of Inspiratory Muscle Training on Pulmonary Function, Functional Capacity, and Quality of Life After Percutaneous Vertebroplasty in Individuals With Osteoporotic Vertebral Compression Fracture"

Vertebral compression fractures (VCFs) are among the most common complications of osteoporosis. In a Germany-based study, the annual incidence of VCFs in individuals aged 50 and above was reported as 307 per 100,000 people. The same study estimated the direct healthcare cost of VCFs to be approximately €6,490 within the first year after the fracture. The risk of VCF increases with age in both sexes, with a 40% rise in postmenopausal women. Although there is no specific epidemiological study on the incidence of VCFs in Turkey, a study conducted in 2025 reported an increased incidence of osteoporotic vertebral fractures due to limited access to healthcare and significantly reduced physical activity during the COVID-19 pandemic. Approximately one-third of osteoporotic VCFs are symptomatic and significantly reduce patients' quality of life. Whether symptomatic or asymptomatic, osteoporotic VCFs can lead to various health issues such as spinal deformities, nerve damage, functional limitations in thoracic and abdominal organs, reduced mobility, impaired pulmonary function, depression, and decreased quality of life. These fractures are also a major cause of acute and chronic back pain and are associated with increased risk of new fractures and mortality.

Percutaneous vertebroplasty (PV) is a minimally invasive procedure commonly used in the treatment of spinal pain caused by osteoporotic fractures, vertebral hemangiomas, and metastatic tumors. First performed by Deramond et al. in 1987 for spinal hemangiomas, PV has since been widely adopted as an effective treatment for osteoporotic and neoplastic vertebral fractures. During the procedure, under fluoroscopic or CT guidance, polymethyl methacrylate (PMMA) cement is injected into the fractured or weakened vertebral body through a specialized needle. Early studies reported significant pain reduction following the procedure with rare complications. Even before being fully supported by high-quality randomized controlled trials, PV was incorporated into clinical practice and became part of standard treatment for osteoporotic vertebral fractures. Cadaveric studies have also shown that vertebral body rigidity and mechanical strength are restored following PMMA injection.

Spinal pathologies such as vertebral fractures and deformities are known to cause restrictive pulmonary dysfunctions. Restrictive lung diseases encompass conditions characterized by reduced lung expansion capacity due to etiologies such as pulmonary fibrosis, neuromuscular diseases, and thoracic deformities. These conditions are associated with decreased total lung capacity (TLC), vital capacity (VC), and functional residual capacity (FRC), leading to impaired alveolar ventilation and increased respiratory muscle workload. Vertebral deformities, in particular, restrict chest wall mobility, preventing optimal function of respiratory muscles and reducing ventilatory capacity. The progressive nature of spinal deformities can reduce diaphragmatic mechanical efficiency and increase the work of breathing. Studies have shown a significant correlation between the degree of vertebral deformity and the degree of pulmonary dysfunction. A 2022 systematic review reported that increased Cobb angle in untreated idiopathic scoliosis is inversely related to forced vital capacity (FVC), VC, and TLC. Similarly, another study on adolescents who underwent thoracoplasty surgery for idiopathic scoliosis showed a significant postoperative decline in respiratory function.

Moreover, changes in respiratory function after PV are not solely due to pain reduction and mechanical improvements, but may also be influenced by physiological effects related to the surgery itself. Local tissue trauma during PV may affect the structural and functional integrity of paraspinal muscles in adjacent vertebral segments. This can result in inflammatory responses, spasms, or inhibition of paraspinal muscles, impairing spinal stability and indirectly limiting chest wall mobility. Additionally, protective breathing patterns due to postoperative pain may lead to dominant apical breathing instead of diaphragmatic breathing, causing inefficient respiratory muscle activity and reduced ventilation efficiency. Considering these physiological impacts, targeted inspiratory muscle training (IMT) in the postoperative period is viewed as a clinically important intervention to prevent or mitigate these adverse outcomes.

Although short-term improvements in pulmonary function following PV have been reported, there is no existing study that compares these improvements with healthy individuals. This creates uncertainty in determining the sufficiency and sustainability of post-PV functional gains relative to the pulmonary performance of the general population. Furthermore, most studies evaluating pulmonary function after PV provide limited long-term follow-up data, making it unclear whether the initial improvements are maintained or whether a decline occurs over time. IMT is thought to have the potential to support and enhance pulmonary function in the long term following PV. Studies have shown that IMT improves respiratory muscle strength, thoracic mobility, and dyspnea symptoms in patients undergoing thoracic surgery, and these effects are sustained in long-term follow-ups. Therefore, implementing IMT in patients after PV is clinically important to preserve the surgical gains, reduce pulmonary complications, and improve quality of life.