Summary
The results of the FREE-study encourage the use of kyphoplasty to stabilize osteoporotic compression fractures, and will have major impact on reimbursement of kyphoplasty in Europe and the rest of the world. Already after 1 month pain (VAS), Quality of Life (EQ5D), and function (SF-36) is significantly improved, if kyphoplasty is used to stabilize osteoporotic vertebral compression fractures, which is pertained during one year followup.
Analysis
I. Osteoporotic Vertebral Compression Fractures:
Millions of elderly people worldwide suffer from osteoporosis and pathological osteoporotic fractures. The annual incidence of VCF is 1.21% in women and 0.68% in men, increasing markedly with age (Felsenberg et al. 2002). With the continued aging of our population, VCF represent an important cause of disability and a significant source of healthcare resource utilization (Lad et al. 2007). For decades non-surgical management with pain control and physical therapy-assisted mobilization has been the only treatment option and has proven successful in many cases. However, many patients remain immobilized due to chronic back pain (Pluijm et al. 2000). The obvious functional and physical consequences of VCF lead to anxiety, depression, and have devastating impact on interpersonal relationships and social roles (Gold et al. 1996). One should be aware of the fact that untreated VCF contribute significantly to shorter life-expectancy both in women (p<0.01) and men (p<0.0001) within one year after onset of symptoms (Center et al. 1999).
II. Treatment Options
Besides the dramatic improvement of medical therapy of osteoporosis, the restoration of quality of life has grown into a major issue in VCF treatment. Therefore operative treatment for early pain reduction and correction of deformity has been much sought-after. Galibert et al (1987) presented the first cases of successful vertebral augmentation by intravertebral injection of polymethyl methacrylate (PMMA) in patients with vertebral haemagiomas. Later, vertebroplasty was successfully introduced for the management of osteoporotic compression fractures (Deramond 1998). The primary goal of vertebroplasty is pain relief by stabilization of the continuously sintering VCF. A significant drawback of vertebroplasty is the fact that prevalent kyphosis cannot be corrected through this procedure. The biomechanical understanding of increasing anterior column load with progressing kyphosis leading to subsequent VCF established the basic rationale for kyphoplasty. With this technique, reduction of VCF is achieved by a transpedicular intracorporal balloon expansion and retention by PMMA cement augmentation (Voggenreiter 2005). Up to present, the concept of kyphoplasty has been applied in thousands of patients with VCF, by rapidly decreasing fracture-related pain, improving pulmonary function and quality of life (Yang et al 2007; Wardlaw et al. 2007). Nevertheless the conservative medical therapy will not be easily replaced, since lack of reimbursement in most countries causes an economic burden, many patients are not willing to take. Furthermore it is still unclear whether the benefits of kyphoplasty outweigh its complications (Robinson et al 2008). The results of the multicentrical randomized controlled FREE-trial were long-awaited for and will give us further evidence (Wardlaw et al. 2009).
III . Results and Complications of Kyphoplasty
Even though the name kyphoplasty implicates the reduction of a wedge-formed compression fracture, primary goal with kyphoplasty is improvement of function and quality of life. Pain reduction is improved with vertebral cement augmentation. Kyphoplasty has the great advantage of using a balloon to create a pre-shaped cavity which will be filled with a very viscous cement produced by Kyphon itself (KyphX-H), a cement that is much less fluid than vertebroplasty-cement and thus has less cement leakage problems than vertebroplasty procedures.
Nevertheless kyphoplasty has its complications (Robinson et al 2008). The comprehensive meta-analysis of Taylor et al (2007) summarized all published kyphoplasty complications. Cement leakages occurred in 8.1% of all cases, but only 0.09% were symptomatic. New vertebral fractures occurred in 11.1%, and 9.4% were adjacent vertebrae. Pulmonary embolism occurred in 0.17% of all cases. Spinal stenosis with spinal cord compression occurred in 0.16% of all cases. Radiculopathy was found in 0.17% of all cases. The overall mortality was 4.4%, perioperative mortality was 0.13%.
IV. One Year Followup Results of the FREE-Study
The Fracture Reduction Evaluation (FREE) study enrolled 2003 to 2005 in 21 sites in Europe 300 patients with osteoporotic VCF. These were randomised to kyphoplasty treatment (n=149) or non-surgical treatment (n=151). Endpoints were function as measured by SF-36 PCS, Pain as measured with the Visual Analogous Scale (VAS), and Quality of Life measured with the EQ5D. Results were analysed by intention-to-treat analysis.
After one month the mean SF-36 PCS score improved by 7.2 points (95% CI 5.7–8.8), from 26.0 at baseline to 33.4 at 1 month, in the kyphoplasty group, and by 2.0 points (0.4–3.6), from 25.5 to 27.4, in the non-surgical group (difference between groups 5.2 points, 2.9–7.4; p<0.0001). Compared with controls, the kyphoplasty group had greater improvements in quality of life as assessed by the EQ-5D questionnaire from baseline to 1 month (difference between groups 0.18 points, 0.08–0.28; p=0.0003) and from baseline to 12 months (0.12 points, 0.01–0.22; p=0.0252). Back pain score decreased by 2.2 points (1.6–2.8; p<0.0001) more in the kyphoplasty group than in controls at 1 week and by 0.9 points (0.3–1.5; p=0.0034) after 12 months. The kyphoplasty group also had a greater reduction than had controls in the percentage of patients needing narcotic analgesics between 1 month and 6 months.
The results of this randomised trial are similar to those of two small controlled but non-randomised studies that show that kyphoplasty treatment was associated with greater improvement in back pain and physical functioning than non-surgical management for at least 6 months (Komp M et al. 2004) and 12 months (Garfin et al 2001).
V. Implications for Healthcare Professionals
Even though a thorough cost-benefit analysis of the FREE-study data must follow, th significant clinical benefit of patients with VCF treated with kyphoplasty will pressure governments and healthcare providers to widen the reimbursement of kyphoplasty. In countries, where kyphoplasty is fully reimbursed (i e Germany) hundreds of thousands of kyphoplasties have been performed. Other countries (i e Sweden) where reimbursement is not case-related, but a chronically undersized budget is distributed to prioritised diseases, government officials will have to discuss the priority of kyphoplasty in a public health context.
Nevertheless this study will be an important tool for Medtronic to expand the regions where kyphoplasty is used and reimbursed.
