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Percutaneous vertebroplasty for treatment of thoracolumbar spine bursting fracture
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Letters to the editor / Surgical Neurology 64 (2005) 95 – 97
Also, several patients with TBM might have a combination of obstructive and communicating hydrocephalus. Therefore, we would not rely on cerebrospinal fluid dynamic studies to select patients with TBM for ETV. In other words, we would not deny ETV to a patient with TBM who has failed shunt surgery, even if cerebrospinal fluid flow studies indicate a communicating type of hydrocephalus.
References [1] Gangemi M, Maiuri F, Bounamassa S, Colella G, de Divitiis E. Endoscopic third ventriculostomy in idiopathic normal pressure hydrocephalus. Neurosurgery 2004;55:129 - 34. [2] Jonathan A, Rajshekhar V. Endoscopic third ventriculostomy for chronic hydrocephalus after tuberculous meningitis. Surg Neurol 2005;63:32 - 5. [3] Mitchel P, Mathew R. Third ventriculostomy in normal pressure hydrocephalus. Br J Neurosurg 1999;13:382 - 5.
Vedantam Rajshekhar, MCh Ashish Jonathan, MBBS Department of Neurological Sciences Christian Medical College Vellore 632 004, India DOI of original article 10.1016/j.surneu.2005.03.029 doi:10.1016/j.surneu.2005.03.030
Percutaneous vertebroplasty for treatment of thoracolumbar spine bursting fracture Chen JF, Lee ST. Surg Neurol 2004;62:494-500 With great interest we read the article by Chen and Lee on the use of percutaneous vertebroplasty for the treatment of thoracolumbar burst fracture. In this article, the authors describe a small series of patients with traumatic thoracolumbar fractures who were treated with percutaneous vertebroplasty several months after initial treatment, consisting of recumbency, bracing, and analgesics, failed. The authors claim a statistically significant reduction in pain and improvement in mobility almost immediately after the experimental procedure and conclude that, although cement leakage frequently occurs, percutaneous vertebroplasty can be an alternative treatment method for highly selected patients. The patients were selected after demonstrating insufficient response to conservative treatment, from a cohort of 21 patients with thoracolumbar burst fractures. Two more patients underwent surgery because of progressive neurological deficits leading to a conservative treatment failure percentage of 38% (8/21) in this series, which is unusually high compared to clinical studies published recently [2,3]. It is not completely clear to us in what respect the current patients or treatment regime differed from those earlier studies. It is clear, however, that, as the mean interval between trauma and percutaneous vertebroplasty was 5.2 months (range, 3.5-8 months), none
of the fractures was fresh. This characteristic of all 6 patients is, in our opinion, not given enough attention by the authors in the title or conclusions. We suggest that the conclusion should read that percutaneous vertebroplasty might play a limited role in the treatment of thoracolumbar fractures after conservative treatment has failed. In acute traumatic thoracolumbar fractures, the proposed treatment of percutaneous vertebroplasty might seriously harm patients because of 3 phenomena. First, the injection of polymethyl methacrylate cement in a fragmented vertebral body, held mainly together by the adjacent annulus fibrosis fibers, longitudinal ligaments, and surrounding soft tissue, might cause a volume expansion in a radial direction potentially leading to spinal cord compression. A fracture reduction effect is not to be expected from cement injection and should certainly not be attempted as pressurization can lead to extracorporal cement leakage. Second, in osteoporotic collapsed vertebral bodies the posterior vertebral body wall is typically intact and leakage in the spinal canal will therefore rarely occur. However, in thoracolumbar burst fractures (A3 according to the AO classification) the posterior vertebral body wall is, per definition, fractured, and cement leakage in the spinal canal is much more likely to develop. As the incidence of cement leakage is probably already underestimated because of suboptimal intraoperative and postoperative imaging techniques, leakage of polymethyl methacrylate cement in the spinal canal might be expected in at least, some patients [1]. Third, the authors state in the bDiscussionQ section that bthe polymethyl methacrylate cement should clearly fill the gaps between the bone fragments and thus hold the fragments tightly, and not just be inserted only into the osteoporotic trabeculae of the damaged vertebra.Q We do not think that polymethyl methacrylate is able to hold multiple fragments tightly but can only fill voids, a concern already expressed by Dr Kalfas in the commentary after the article. In acute thoracolumbar fractures the proposed technique should not be performed until all the above issues are resolved. In patients with older fractures and disabling back pain refractory to conservative treatment, the use of calcium phosphate cements, which are biocompatible, osteoconductive, and set isothermically, should deserve consideration over polymethyl methacrylate cement.
References [1] Schmidt R, Cakir B, Mattes T, Wegener M, Puhl W, Richter M. Cement leakage during vertebroplasty: an underestimated problem? Eur Spine J 2005. [2] Shen WJ, Liu TJ, Shen YS. Nonoperative treatment versus posterior fixation for thoracolumbar junction burst fractures without neurologic deficit. Spine 2001;26:1038 - 45. [3] Wood K, Butterman G, Mehbod A, Garvey T, Jhanjee R, Sechriest V. Operative compared with nonoperative treatment of a thoracolumbar burst fracture without neurological deficit. A prospective, randomized study. J Bone Joint Surg Am 2003;85-A:773 - 81.
Letters to the editor / Surgical Neurology 64 (2005) 95 – 97
J.J. Verlaan F.C. Oner Department of Orthopaedics University Medical Center Utrecht 3584CX Utrecht, The Netherlands E-mail address: [email protected] DOI of original article 10.1016/j.surneu.2003.10.049 doi:10.1016/j.surneu.2005.03.031
Response We appreciate Dr Verlann’s comments about our recent publication on percutaneous vertebroplasty (PVP) for the treatment of burst fractures. We agree that the pathophysiology of osteoporotic compression fractures is quite different from traumatic bursting spinal fractures because of considerable differences in the pathophysiology, treatment, and prognosis [5]. We know that every surgical procedure has potential risk, and the morbidity rate depends on the disease itself, the surgical procedure, and the surgeon’s ability. In patients with acute bursting fracture of thoracic or lumbar spine without neurological deficit, conservative treatment is the first choice. In these patients, if the conservative treatment failed, then surgical treatment should be considered. The case we reported, and a subsequent study, also demonstrated that PVP is an effective way to treat this condition [1,2]. We suggested that the fracture treated with PVP should be limited to anterior and middle column and with intact posterior longitudinal ligament. Whether a bursting fracture with retropulsion of bone into the spinal canal can undergo closed reduction and be treated with PVP needs further study [3]. There are several different factors for our patients as compared to conventional PVP techniques. As regards technique, the needles should be inserted within the anterior gaps of the burst fracture, not only into the vertebra. The polymethyl methacrylate (PMMA) should clearly fill the gaps between the bone fragments (at anterior column) and
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thus hold the fragments tightly, and not just be inserted only into the osteoporotic trabeculae of the damaged vertebra. Under fluoroscopic examination, the PMMA is distributed as a focal mass within anterior column of the damaged vertebra, and not diffusely distributed within the whole vertebra. Most important for this kind of treatment is not to fill all the fracture site with bone cement but to leave some fracture space for further bony fusion. The case we reported, and the subsequent study, also proved that there was bony fusion of these fractures [1,2]. Finally, we should emphasize that this procedure inherits potential risk of extravasations of PMMA, and should be used with extreme caution by experienced surgeons. A syringe compressor for controlled delivery of the bone cement is also important to avoid the leakage of bone cement [4]. Whether PVP can effectively treat the acute bursting fracture needs further study. References [1] Chen JF, Lee ST. Percutaneous vertebroplasty for the treatment of thoracolumbar spine bursting fractures. Surg Neurol 2004;62:494 - 500. [2] Chen JF, Wu CT, Lee ST. Percutaneous vertebroplasty for the treatment of burst fractures. J Neurosurg (Spine 1) 2004;2:228 - 31. [3] Lee ST, Chen JF. Closed reduction vertebroplasty for the treatment of osteoporotic vertebral compression fractures. J Neurosurg (Spine 4) 2004;100:392 - 6. [4] Lee ST, Chen JF. A syringe compressor for vertebroplasty: technique note. Surg Neurol 2004;61:580 - 4. [5] Wu CT, Lee SC, Lee ST, Chen JF. Classification of symptomatic osteoporotic compression fractures of the thoracic and lumbar spine. J Clin Neurosci [in press].
Shih-Tseng Lee, MD Jyi-Feng Chen, MD Chieh-Tsai Wu, MD Department of Neurosurgery Chang Gung University and Chang Gung Memorial Hospital Taoyuan, Taiwan Republic of China DOI of original article 10.1016/j.surneu.2005.03.031 doi:10.1016/j.surneu.2005.03.032
Letters to the editor / Surgical Neurology 64 (2005) 95 – 97
Also, several patients with TBM might have a combination of obstructive and communicating hydrocephalus. Therefore, we would not rely on cerebrospinal fluid dynamic studies to select patients with TBM for ETV. In other words, we would not deny ETV to a patient with TBM who has failed shunt surgery, even if cerebrospinal fluid flow studies indicate a communicating type of hydrocephalus.
References [1] Gangemi M, Maiuri F, Bounamassa S, Colella G, de Divitiis E. Endoscopic third ventriculostomy in idiopathic normal pressure hydrocephalus. Neurosurgery 2004;55:129 - 34. [2] Jonathan A, Rajshekhar V. Endoscopic third ventriculostomy for chronic hydrocephalus after tuberculous meningitis. Surg Neurol 2005;63:32 - 5. [3] Mitchel P, Mathew R. Third ventriculostomy in normal pressure hydrocephalus. Br J Neurosurg 1999;13:382 - 5.
Vedantam Rajshekhar, MCh Ashish Jonathan, MBBS Department of Neurological Sciences Christian Medical College Vellore 632 004, India DOI of original article 10.1016/j.surneu.2005.03.029 doi:10.1016/j.surneu.2005.03.030
Percutaneous vertebroplasty for treatment of thoracolumbar spine bursting fracture Chen JF, Lee ST. Surg Neurol 2004;62:494-500 With great interest we read the article by Chen and Lee on the use of percutaneous vertebroplasty for the treatment of thoracolumbar burst fracture. In this article, the authors describe a small series of patients with traumatic thoracolumbar fractures who were treated with percutaneous vertebroplasty several months after initial treatment, consisting of recumbency, bracing, and analgesics, failed. The authors claim a statistically significant reduction in pain and improvement in mobility almost immediately after the experimental procedure and conclude that, although cement leakage frequently occurs, percutaneous vertebroplasty can be an alternative treatment method for highly selected patients. The patients were selected after demonstrating insufficient response to conservative treatment, from a cohort of 21 patients with thoracolumbar burst fractures. Two more patients underwent surgery because of progressive neurological deficits leading to a conservative treatment failure percentage of 38% (8/21) in this series, which is unusually high compared to clinical studies published recently [2,3]. It is not completely clear to us in what respect the current patients or treatment regime differed from those earlier studies. It is clear, however, that, as the mean interval between trauma and percutaneous vertebroplasty was 5.2 months (range, 3.5-8 months), none
of the fractures was fresh. This characteristic of all 6 patients is, in our opinion, not given enough attention by the authors in the title or conclusions. We suggest that the conclusion should read that percutaneous vertebroplasty might play a limited role in the treatment of thoracolumbar fractures after conservative treatment has failed. In acute traumatic thoracolumbar fractures, the proposed treatment of percutaneous vertebroplasty might seriously harm patients because of 3 phenomena. First, the injection of polymethyl methacrylate cement in a fragmented vertebral body, held mainly together by the adjacent annulus fibrosis fibers, longitudinal ligaments, and surrounding soft tissue, might cause a volume expansion in a radial direction potentially leading to spinal cord compression. A fracture reduction effect is not to be expected from cement injection and should certainly not be attempted as pressurization can lead to extracorporal cement leakage. Second, in osteoporotic collapsed vertebral bodies the posterior vertebral body wall is typically intact and leakage in the spinal canal will therefore rarely occur. However, in thoracolumbar burst fractures (A3 according to the AO classification) the posterior vertebral body wall is, per definition, fractured, and cement leakage in the spinal canal is much more likely to develop. As the incidence of cement leakage is probably already underestimated because of suboptimal intraoperative and postoperative imaging techniques, leakage of polymethyl methacrylate cement in the spinal canal might be expected in at least, some patients [1]. Third, the authors state in the bDiscussionQ section that bthe polymethyl methacrylate cement should clearly fill the gaps between the bone fragments and thus hold the fragments tightly, and not just be inserted only into the osteoporotic trabeculae of the damaged vertebra.Q We do not think that polymethyl methacrylate is able to hold multiple fragments tightly but can only fill voids, a concern already expressed by Dr Kalfas in the commentary after the article. In acute thoracolumbar fractures the proposed technique should not be performed until all the above issues are resolved. In patients with older fractures and disabling back pain refractory to conservative treatment, the use of calcium phosphate cements, which are biocompatible, osteoconductive, and set isothermically, should deserve consideration over polymethyl methacrylate cement.
References [1] Schmidt R, Cakir B, Mattes T, Wegener M, Puhl W, Richter M. Cement leakage during vertebroplasty: an underestimated problem? Eur Spine J 2005. [2] Shen WJ, Liu TJ, Shen YS. Nonoperative treatment versus posterior fixation for thoracolumbar junction burst fractures without neurologic deficit. Spine 2001;26:1038 - 45. [3] Wood K, Butterman G, Mehbod A, Garvey T, Jhanjee R, Sechriest V. Operative compared with nonoperative treatment of a thoracolumbar burst fracture without neurological deficit. A prospective, randomized study. J Bone Joint Surg Am 2003;85-A:773 - 81.
Letters to the editor / Surgical Neurology 64 (2005) 95 – 97
J.J. Verlaan F.C. Oner Department of Orthopaedics University Medical Center Utrecht 3584CX Utrecht, The Netherlands E-mail address: [email protected] DOI of original article 10.1016/j.surneu.2003.10.049 doi:10.1016/j.surneu.2005.03.031
Response We appreciate Dr Verlann’s comments about our recent publication on percutaneous vertebroplasty (PVP) for the treatment of burst fractures. We agree that the pathophysiology of osteoporotic compression fractures is quite different from traumatic bursting spinal fractures because of considerable differences in the pathophysiology, treatment, and prognosis [5]. We know that every surgical procedure has potential risk, and the morbidity rate depends on the disease itself, the surgical procedure, and the surgeon’s ability. In patients with acute bursting fracture of thoracic or lumbar spine without neurological deficit, conservative treatment is the first choice. In these patients, if the conservative treatment failed, then surgical treatment should be considered. The case we reported, and a subsequent study, also demonstrated that PVP is an effective way to treat this condition [1,2]. We suggested that the fracture treated with PVP should be limited to anterior and middle column and with intact posterior longitudinal ligament. Whether a bursting fracture with retropulsion of bone into the spinal canal can undergo closed reduction and be treated with PVP needs further study [3]. There are several different factors for our patients as compared to conventional PVP techniques. As regards technique, the needles should be inserted within the anterior gaps of the burst fracture, not only into the vertebra. The polymethyl methacrylate (PMMA) should clearly fill the gaps between the bone fragments (at anterior column) and
97
thus hold the fragments tightly, and not just be inserted only into the osteoporotic trabeculae of the damaged vertebra. Under fluoroscopic examination, the PMMA is distributed as a focal mass within anterior column of the damaged vertebra, and not diffusely distributed within the whole vertebra. Most important for this kind of treatment is not to fill all the fracture site with bone cement but to leave some fracture space for further bony fusion. The case we reported, and the subsequent study, also proved that there was bony fusion of these fractures [1,2]. Finally, we should emphasize that this procedure inherits potential risk of extravasations of PMMA, and should be used with extreme caution by experienced surgeons. A syringe compressor for controlled delivery of the bone cement is also important to avoid the leakage of bone cement [4]. Whether PVP can effectively treat the acute bursting fracture needs further study. References [1] Chen JF, Lee ST. Percutaneous vertebroplasty for the treatment of thoracolumbar spine bursting fractures. Surg Neurol 2004;62:494 - 500. [2] Chen JF, Wu CT, Lee ST. Percutaneous vertebroplasty for the treatment of burst fractures. J Neurosurg (Spine 1) 2004;2:228 - 31. [3] Lee ST, Chen JF. Closed reduction vertebroplasty for the treatment of osteoporotic vertebral compression fractures. J Neurosurg (Spine 4) 2004;100:392 - 6. [4] Lee ST, Chen JF. A syringe compressor for vertebroplasty: technique note. Surg Neurol 2004;61:580 - 4. [5] Wu CT, Lee SC, Lee ST, Chen JF. Classification of symptomatic osteoporotic compression fractures of the thoracic and lumbar spine. J Clin Neurosci [in press].
Shih-Tseng Lee, MD Jyi-Feng Chen, MD Chieh-Tsai Wu, MD Department of Neurosurgery Chang Gung University and Chang Gung Memorial Hospital Taoyuan, Taiwan Republic of China DOI of original article 10.1016/j.surneu.2005.03.031 doi:10.1016/j.surneu.2005.03.032