A vertebral compression fractures is defined as a traumatic fracture of one or more healthy body(ies) or traumatic or spontaneous fracture of one or more vertebral body(ies) weakened by osteoporosis, tumor invasion, or infection (Osteomyelitis).1 As of 2005, osteoporosis accounted for approximately 547,000 vertebral compression fractures with an estimated medical cost of 16.9 billion dollars 1. It should be noted that women with at least one vertebral fracture have an associated age-adjusted risk for mortality that is at least 30% higher when compared with women without a previous vertebral fracture.2
Balloon kyphoplasty is a relatively new treatment to treat compression fractures. It was devloped in the 1990's and combines angioplasty and vertebroplasty. According to Wardlaw et al., "Balloon kyphoplasty is a minimally invasive procedure that is intended to reduce pain, disability, and vertebral deformity by use of catheters with inflatable bone tamps placed inside the affected veterbral body".3 The procedures works by pushing the endplates of the vertebral body apart effectively restoring the height and correcting angular deformities of the compressed vertebrae.
For a brief review of vertebral anatomy reference the video below.
Typically, kyphoplasty and vertebroplasty are used is patients who are suffering from osteoporosis related compression fractures. However, this type of treatment can be used in patients who have vertebral damage resulting from malignant tumors or osteomyelitis as well. Patients who receive this type of treatment are generally not responding to progressive treatment (or not tolerating it well and still present with pain). Some of these patients may even present with progressive collapse of the vertebral body and kyphosis with or without neurological deficit.4,5. In these cases, aggressive treatment is needed but patients with osteoporosis are not ideal candidates for surgical fixation due to the poor quality of osteporotic bone. 4,5
IV. Potential Etiologies/Risk Factors for Developing A Vertebral Fracture:1
- tumor invasion of the spine
V. Diagnostic Tests/Clinical Presentation:6
- A physical examination with evidence of kyphosis. Also, there may be tenderness upon palpation of the involved vertebra
- A spine x-ray with evidence of compression fracture
- A bone density scan to assess for osteoporosis
- A CT or MRI scan if there is evidence of a tumor, or if the fracture was caused by high-energy trauma
VI. Conservative Treatment:
Conservative management is almost always the first choice of treatment for vertebral compression fractures, except when surgery is indicated such as patients with spinal instability and in those patients with neurological indications.1 Conservative management includes various combination of analgesics, bed rest, external fixation using braces or casting, and physical rehabilitation1. Spinal braces are used to help the patient maintain extension and to prevent flexion7. Examples of braces that may be used include the CASH or Jewett brace, semirigid Taylor-type brace, and a dorsolumbar corset.
Commonly used rehabilitation and physical therapy techniques (this applies only to anterior compression fractures with posterior structures intact) include7:
- TENS for pain relief
- While there is little evidence currently on the use of TENS for treatment of compression fractures, there is evidence of its effectiveness for pain relief of other disorders of the spine.8,9. However, other studies have demonstrated that there are no long term benefits of TENS for pain reduction. Furthermore, other modalities (interferential current, electrical muscle stimulation, ultrasound, cold/hot packs) have been not been studied enough or shown effective enough to warrant there use for the treatment of back pain.10
- Patient education about positions/activities that are beneficial or potentially harmful
- Encourage positions/activities that promote spinal extension and avoid flexion
- Teach patient to log-roll to side when getting out of bed
- Using a good lumbar support when sitting
- Walking and other weight bearing activities to help prevent further demineralization
- Active and passive extension exercises as soon as the patient's pain is decreased to the point that these may be tolerated
- Progress eventually to postural exercises
There are some problems associated with conservative treatment. With conservative treatment the vertebral compression fracture almost always heals in response to treatment modalities. However, it has been noted that "1/3 of patients report persistent pain, progressive functional limitations, and loss of mobility"1. Additionally, conservative treatment does not target loss of height and kyphosis related to compression fractures. Some patients may even have reduced pulmonary function and present with impaired balance if vertebral deformity is left untreated.3
When surgery was required, compression fractures were initially treated with open stabilization procedures.11 This is still a reasonable option for patients that are younger and have a compression fracture resulting from trauma that is not osteoporosis related. However, for patients that are older this is not a reasonable treatment due to the risk of the surgery with ORIF and/or the presence of osteoporosis. In order to address, this problem two procedures have been developed to treat vertebral compression fractures in a less invasive way. These two procedures are vertebroplasty and kyphoplasty. Balloon kyphoplasty was originally designed to treat the kyphotic deformity while vertebroplasty was developed to "stabilze" the deformity.1 Eck et al. found that, "Both vertebrplasty and kyphoplasty provided significant improvement in visual analog pain scale (VAS) scores. Vertebroplasty had significantly greater improvement in pain scales but also had greater risk of cement leakage."8
Vertebroplasty involves percutaneous injection, through the pedicles (usually a transpedicular route), of a low viscosity bone cement, into a collapsed vertebral body, under fluoroscopic guidance. The cement usually used in polymethylmethacrylate (PMMA).
Kyphoplasty is similar to vertebroplasty in the fact that cement is injected through the pedicles (transpedicular or extrapedicular) into the vertebral body using fluoroscopy. However, the difference is that kyphoplasty uses a balloon tamp that is inserted into the collapsed vertebral body. Then the balloon is inflated in order to create a cavity in the cancellous bone and if possible reallignment of the endplate of the vertebral body is achieved. The tamp is then removed and PMMA is injected in order to stabilize the fracture.
Kyphoplasty is a much more demanding procedure than vertebroplasty. The reason is that proper placement of the balloon is essential and several steps need to be taken before the cement is applied1
Currently, the surgeon performing the kyphoplasty has the option to either use a unilateral or bilateral technique. Chung et al., found "that the bilateral approach had a greater advantage in the reduction of the kyphosis and the loss of future reduction was less than the unilateral approach".4
VIII. Complication of vertebroplasty and balloon kyphoplasty
Like any procedure vertebroplasty and kyphoplasty involve potential complications. However, it should be noted that both of these procedures carry less risk compared to open surgery. The rate of major complications is <1% for vertebroplasty and <5% for kyphoplasty for treated patients with osteoporotic and neoplastic fractures.2 Major complications include pulmonary emoblism, neurologic defecits, infection, rib fractures, and adjacent-level vertebral compression fractures.2