|
|||||
|
|
||||||
© 2002 American Society for Clinical Oncology Kyphoplasty in the Treatment of Osteolytic Vertebral Compression Fractures as a Result of Multiple MyelomaByFrom the Department of Orthopaedics and Minimally Invasive Surgery Center, Cleveland Clinic Foundation; and the Multiple Myeloma Program, the Cleveland Clinic Tausig Cancer Center, Cleveland, OH. Address reprint requests to I.H. Lieberman, MD, Department of Orthopaedics, Minimally Invasive Surgery Center, 9500 Euclid Ave Desk A-41, Cleveland, Ohio, 44195; email: lieberi{at}ccf.org
PURPOSE: We prospectively evaluated the safety and efficacy of kyphoplasty in the treatment of osteolytic vertebral compression fractures resulting from multiple myeloma. The principle symptoms in multiple myeloma result from bone destruction, especially the spine. Kyphoplasty is a new technique that involves the introduction of inflatable bone tamps (IBT) into the vertebral body. The purpose of the IBT is to restore the vertebral body back toward its original height, while creating a cavity that can be filled with highly viscous bone cement. PATIENTS AND METHODS: Fifty-five consecutive kyphoplasty procedures were performed in 18 patients with osteolytic vertebral compression fractures resulting from multiple myeloma. Cement leakage and any complications were recorded. Early objective analysis was made by comparing preoperative and latest Short Form 36 Health Survey scores. Height restoration was estimated by measuring vertebral height on lateral radiographs. RESULTS: The mean age of patients was 63.5 years, mean duration of symptoms was 11 months, and mean follow-up was 7.4 months. There were no major complications related directly to use of this technique. On average, 34% of height lost at the time of fracture was restored. Asymptomatic cement leakage occurred at two (4%) of 55 levels. Significant improvement in SF36 scores occurred for Bodily Pain (23.2 to 55.4, P = .0008), Physical Function (21.3 to 50.6, P = .0010), Vitality (31.3 to 47.5, P = .010), and Social Functioning (40.6 to 64.8, P = .014). CONCLUSION: Kyphoplasty was efficacious in the treatment of osteolytic vertebral compression fractures resulting from multiple myeloma. Kyphoplasty is associated with early clinical improvement of pain and function as well as some restoration of vertebral body height.
MULTIPLE MYELOMA IS a tumor of B-cell origin. Estimates of bone involvement at presentation vary from 70% to 100% of patients. The principle morbidity in the disease is as a result of skeletal involvement, particularly the spine. Myeloma causes the resorption of bone by stimulating osteoclasts via osteoclast-activating factors.1 The present treatments for multiple myeloma include radiotherapy and chemotherapy to control the disease and bisphosphonates to deter bone destruction. Unfortunately, multiple myeloma is presently still incurable; however, survival rates are steadily improving. Myelomatous osteolytic destruction of the spinal column is common and has become more of a clinical issue with the prolonged survival rates. Typically, the diffuse involvement that occurs results in painful progressive vertebral compression fractures at multiple levels over time. Treatment with bed rest, bracing, and analgesics are the standard of care for most of these patients and have proven to be of limited benefit, especially when considering the progressive spinal kyphosis and its subsequent consequences. Cement augmentation of the vertebral body has been used for the relief of pain in the spine as a result of tumor involvement since it was first described by Gallibert in 1984.2 This technique of vertebroplasty involves the injection of low-viscosity liquid bone cement (poly-methyl-methacrylate [PMMA]) into the damaged vertebral body via a percutaneous approach under image guidance. This technique has been shown to relieve pain in unstable vertebral fractures caused by tumor and in osteoporotic compression fractures. The difficulty with vertebroplasty as a technique is two-fold. It makes no attempt to restore lost vertebral height or correct the resultant spinal deformity. Deformity becomes more important when there is generalized spinal involvement as in multiple myeloma, with multiple fractures occurring over time. The second major difficulty is the very high incidence of cement leakage as a result of forcing liquid bone cement into the closed collapsed space of the vertebral body. The rates of cement leakage are reportedly from 30% to 60%.3-5 Neurologic compression after cement extravasation is a rare but potentially devastating complication. Pulmonary embolus of bone cement has also been reported.6,7 Open surgical decompression in combination with vertebroplasty or surgically controlled vertebroplasty has been advocated by some workers to overcome the difficulty of leakage in vertebroplasty.8 This approach, however, defeats the purpose of a minimally invasive technique. Kyphoplasty is a relatively new technique for cement augmentation of the vertebra. It involves the placement of a trochar into the vertebral body posteriorly followed by the hand drilling of a bone channel in the vertebral body. This allows the passage of a balloon-like inflatable bone tamp (IBT) into the vertebral body. The inflation of the IBT under careful image guidance is designed to produce a cavity within the vertebral body and to restore lost vertebral height.9,10 The creation of the cavity within the vertebra is critical because it allows the insertion of very viscous, partially cured cement into the vertebral body. This is in contrast to the liquid state of cement used in vertebroplasty. The insertion of thick viscous cement into a preformed cavity has been shown to result in a lower rate of cement extravasation in patients with osteoporotic vertebral compression fractures.11 The aim of this study was to determine the safety and efficacy of the kyphoplasty procedure in patients with vertebral compression fractures secondary to multiple myeloma. Furthermore, we aimed to examine the rates of cement leakage, to look for evidence of height restoration and to compare preoperative and early postoperative pain and functional ability in treated patients.
This study was designed as a single cohort using consecutive prospectively gathered data examining cement leakage, radiographic vertebral height restoration, and early outcome in patients with multiple myeloma after kyphoplasty as a treatment for osteolytic painful progressive vertebral compression fractures.
Patients
Kyphoplasty Technique
Measurement of Height Restored: Radiographic Assessment The vertical height of all fractured vertebrae were measured both pre- and postoperatively. Vertebral height was defined as the distance, endplate to endplate, at the center of the vertebral body on the lateral radiograph. The vertical height of the vertebra above the fractured vertebra was also measured to give an estimate of the height of the fractured vertebra before fracture. Calculations were made as follows: height regained = (posttreatment height - pretreatment fractured height); height lost = (estimated prefracture height - pretreatment fractured height); and the percentage of height lost that is now restored = (height regained/height lost) x 100. Multiple radiographs were standardized for magnification by measuring and comparing known landmarks to determine a magnification multiplier. The absolute values in height (mm) before and after treatment were statistically compared using paired nonparametric analysis (Wilcoxon signed rank test). Repeat measurements of the same vertebral levels after a 2-week interval with the same observer demonstrated an error of ± 1.1 mm.
Assessment of Cement Leakage
Measurement of Early Outcome: Clinical Assessment
Patients and Levels All 18 patients tolerated the procedure well. The 55 levels treated ranged from T6 to L5, with the majority of treated levels at the thoracolumbar junction (T11, n = 9; T12, n = 7; L1, n = 8; and L2, n = 7). Twenty-seven percent of levels were at T12 or L1. Postoperatively, all patients were admitted to the 23-hour stay unit. Thirteen patients were discharged home the following morning; 11 were discharged that same afternoon. Three patients stayed for 2 or more days, all for medical/oncologic reasons unrelated to the kyphoplasty procedure.
Safety and Efficacy
Cement Extravasation
Height Restored
SF36 Evaluation
In this phase I study, kyphoplasty was found to be safe and effective in the treatment of painful progressive osteolytic vertebral compression fractures resulting from myelomatous destruction. Kyphoplasty resulted in a marked lowering in the leakage rate of cement compared with previous techniques involving cement augmentation of the vertebral body. On average, without stratifying for chronicity or configuration of fracture, we restored 34% of height lost at the time of fracture. In the vertebral bodies where height was restored, we restored on average 56% of height lost. We have previously examined the safety and efficacy of the kyphoplasty procedure for the treatment of vertebral compression fractures secondary to osteoporosis.11 In that cohort, we found a similarly low rate of cement leakage, a mean height restoration of 48%, and statistically significant improvements in early postoperative SF36 pain and function scores. Previous analysis of vertebroplasty has shown effective pain relief. In this current cohort, we found statistically significant improvement in bodily pain as measured by the SF36 (prekyphoplasty = 23.2, postkyphoplasty = 55.4, P = .0008). Every patient in this group recorded a sustained improvement in pain scores. These encouraging results are in contrast to more recent vertebroplasty reports that show at best a 50% improvement in pain scores in metastatic or myeloma patients13 Cortet et al14 performed vertebroplasty in 37 patients, 29 with metastases and eight with multiple myeloma. They achieved excellent pain relief but had a 72.5% leakage rate, with two patients requiring surgical nerve root decompression.14 Cotten et al15 examined vertebroplasty in a similar group of patients to show that pain relief was not related to percentage filling. It has been reported that between 4 to 8 mL of bone cement is estimated as the volume required to restore strength and stiffness in vertebroplasty.16 This is difficult to achieve with the vertebroplasty technique as evidenced by the significant risk of cement leakage. Symmetrical cement placement has also been suggested to be of importance.17 The short coming of this analysis is in the calculation and reporting of height restored. We have used a simple reproducible method that we have used in previous studies.11 In these myeloma patients, however, it can be difficult to fully differentiate the effects of bone osteolysis caused by tumor versus osteoporosis caused by medications and inactivity. In our previous study, we documented an intraobserver error of ± 1.1 mm. We did document, on average, a 34% restoration of vertebral body height restoration, which is less than that documented in the osteoporotic group (48%). This analysis did not take into account chronicity of collapse or fracture configuration. It is our belief that the osteolysis caused by myeloma results in typically different fracture configurations (usually biconcave fractures) than those seen in true osteoporotic patients (usually wedge compression). Improving therapy and supportive care for myeloma and the probable increase in overall survival18,19 makes effective skeletal care of ever-increasing importance. Even though bisphosphonates have resulted in a significant decrease of skeletal morbidity,19 skeletal damage already sustained at the time of diagnosis as well as the pain resulting from these events limits mobility and, thus, increases morbidity and possibly mortality. The specific advantages of kyphoplasty are that it makes cement augmentation of the vertebrae a safer procedure and provides the opportunity for some restoration in height. The importance of cement leakage cannot be over emphasized. We advocate the use of biplanar fluoroscopy, with continuous screening during actual insertion of cement, and not computed tomography scanning as used by some workers for vertebroplasty. As with any new treatment, the main disadvantage is cost. The cost of kyphoplasty treatment may be offset by the decrease in morbidity, hospital stay, and pain management efforts related to spinal disease in myeloma patients. Kyphoplasty needs to be studied with a prospective economic evaluation of both treatment paths. Multiple myeloma is grossly a very soft vascular tumor, as evidenced by the backflow of blood from the working cannulae during kyphoplasty. The near fluid consistency of the tumor makes it easy for thick cement to displace it and results in impressive cement filling of the vertebra. The effects of dissemination of what is an already widespread disease is not known. We do not suspect any significant systemic effects and have not noted any in this initial group. We were also able to proceed safely with the kyphoplasty in all patients simultaneously with any chemotherapy, provided their WBC count was adequate and coagulation profile was normal. In other fracture types where the posterior wall is deficient, kyphoplasty is presently deemed unsuitable because of the risk of further displacement of bone fragments by the inflation of the balloon. Vertebroplasty has been used in these cases with some success in the past. In these instances, if open reconstruction is not considered appropriate, this may be an indication to consider vertebroplasty. Cement augmentation (vertebroplasty) has been used to treat other tumors including lung adenocarcinoma,20 multiple eosinophilic granuloma,21 and vertebral hemangioma.2,22 Kyphoplasty may have a role in the safe treatment of other disseminated lytic tumor types, and this is currently under investigation. Probably the most significant clinical issue when considering treatment for myeloma patients is the increasing survival time associated with improvements in chemotherapy. Nonetheless, by definition, all patients with multiple myeloma present with bone marrow involvement. The majority of morbidity and mortality is caused by skeletal failure because of bone destruction. Therefore, timely intervention of effective skeletal reconstruction is of ever-increasing importance. Because we have gained experience with the technique and have witnessed the early and sustained clinical improvement in pain and function, we now advocate early treatment of any fractured or collapsing vertebral body. This philosophy should avoid the structural and debilitating functional effects of a progressive spinal kyphotic alignment.
We thank Kyphon Inc, Sunnyvale, CA, for providing the equipment and technical support for this study.
1. Callander NS, Roodman GD: Myeloma bone disease. Semin Hematol 38: 276-285, 2001[CrossRef][Medline] 2. Galibert P, Deramond H: Percutaneous acrylic vertebroplasty as a treatment of vertebral angioma as well as painful and debilitating diseases. Chirurgie 116: 326-334, 1990[Medline] 3. Watts NB, Harris ST, Genant HK: Treatment of painful osteoporotic vertebral fractures with percutaneous vertebroplasty or kyphoplasty. Osteoporos Int 12: 429-437, 2001[CrossRef][Medline] 4. Martin JB, Jean B, Sugiu K, et al: Vertebroplasty: Clinical experience and follow-up results. Bone 25: 11S-15S, 1999[Medline] 5. Ratliff J, Nguyen T, Heiss J: Root and spinal cord compression from methylmethacrylate vertebroplasty. Spine 26: E300-E302, 2001[CrossRef][Medline]
6.
Padovani B, Kasriel O, Brunner P, et al: Pulmonary embolism caused by acrylic cement: a rare complication of percutaneous vertebroplasty. Am J Neuroradiol 20: 375-377, 1999 7. Perrin C, Jullien V, Padovani B, et al: Percutaneous vertebroplasty complicated by pulmonary embolus of acrylic cement. Rev Mal Respir 16: 215-217, 1999[Medline] 8. Wenger M, Markwalder TM: Surgically controlled, transpedicular methyl methacrylate vertebroplasty with fluoroscopic guidance. Acta Neurochir 141: 625-631, 1999[CrossRef][Medline] 9. Belkoff SM, Mathis JM, Fenton DC, et al: An ex vivo biomechanical evaluation of an inflatable bone tamp used in the treatment of compression fracture. Spine 26: 151-156, 2001[CrossRef][Medline]
10.
Belkoff SM, Mathis JM, Deramond H, et al: An ex vivo biomechanical evaluation of a hydroxyapatite cement for use with kyphoplasty. Am J Neuroradiol 22: 1212-1216, 2001 11. Lieberman IH, Dudeney S, Reinhardt MK, et al: Initial outcome and efficacy of "kyphoplasty" in the treatment of painful osteoporotic vertebral compression fractures. Spine 26: 1631-1638, 2001[CrossRef][Medline] 12. Ware JE, Snow KK, Kosinski M, et al: SF36 Health Survey Manual & Interpretation Guide. Boston, MA, Nimrod Press, 1993 13. Barr JD, Barr MS, Lemley TJ, et al: Percutaneous vertebroplasty for pain relief and spinal stabilization. Spine 25: 923-928, 2000[CrossRef][Medline] 14. Cortet B, Cotten A, Boutry N, et al: Percutaneous vertebroplasty in patients with osteolytic metastases or multiple myeloma. Rev Rhum Engl Ed 64: 177-183, 1997[Medline]
15.
Cotten A, Dewatre F, Cortet B, et al: Percutaneous vertebroplasty for osteolytic metastases and myeloma: Effects of the percentage of lesion filling and the leakage of methyl methacrylate at clinical follow-up. Radiology 200: 525-530, 1996 16. Belkoff SM, Mathis JM, Jasper LE, et al: The biomechanics of vertebroplasty the effect of cement volume on mechanical behavior. Spine 26: 1537-1541, 2001[CrossRef][Medline] 17. Liebschner MA, Rosenberg WS, Keaveny TM: Effects of bone cement volume and distribution on vertebral stiffness after vertebroplasty. Spine 26: 1547-1554, 2001[CrossRef][Medline]
18.
Barlogie B, Jagannath S, Desikan K, et al: Total therapy with tandem transplants for newly diagnosed multiple myeloma. Blood 93: 55-65, 1999 19. Berenson A, Lichtenstein A, Porter L, et al: Efficacy of palmidronate in reducing skeletal events in patients with advanced multiple myeloma. N Engl J Med 488-493, 1996 20. Baba Y, Ohkubo K, Hamada K, et al: Percutaneous vertebroplasty for osteolytic metastasis: A case report. Nippon Igaku Hoshasen Gakkai Zasshi 57: 880-882, 1997[Medline] 21. Cardon T, Hachulla E, Flipo RM, et al: Percutaneous vertebroplasty with acrylic cement in the treatment of a Langerhans cell vertebral histiocytosis. Clin Rheumatol 13: 518-521, 1994[CrossRef][Medline] 22. Castel E, Lazennec JY, Chiras J, et al: Acute spinal cord compression due to intraspinal bleeding from a vertebral hemangioma: Two case-reports. Eur Spine J 8: 244-248, 1999[CrossRef][Medline] Submitted September 21, 2001; accepted February 11, 2002.
This article has been cited by other articles:
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|||||||||||
|
Copyright © 2002 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
|