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Frank M Phillips

Publications and source records attributed to Frank M Phillips.

At least 19 recordsLinked to original sources

Comparative effects of bone morphogenetic proteins and sox9 overexpression on extracellular matrix metabolism of bovine nucleus pulposus cells.

STUDY DESIGN: An in vitro biologic study of the effects of adenovirus expressing bone morphogenetic proteins (BMPs) and adenovirus expressing Sox9 on extracellular matrix metabolism by bovine nucleus pulposus cells. OBJECTIVE: To compare the effects of recombinant adenoviral vectors expressing various BMPs (2, 3, 4, 5, 7, 8, 10, 11, 12, 13, 14, and 15) and Sox9 on extracellular matrix accumulation by bovine nucleus pulposus cells. SUMMARY OF BACKGROUND DATA: Nucleus pulposus matrix production may be promoted by transducing the cells with genes that permit the sustained expression of growth factors. The choice of the particular factors or BMPs to be studied for these applications has been largely based on the commercial availability of such products. To our knowledge, this study is the first effort to evaluate systematically the relative effectiveness of the various members of the BMP family in promoting intervertebral disc matrix repair. METHODS: Adult bovine nucleus pulposus cells cultured in monolayer were transduced with adenoviruses expressing human BMP-2, 3, 4, 5, 7, 8, 10, 11, 12, 13, 14, and 15, and adenovirus expressing Sox9. Proteoglycan and collagen accumulation, and cell proliferation were measured 6 days after viral transduction. As a positive control, cells were cultured without any exogenous gene in the presence of recombinant human (rh)BMP-7. RESULTS: Nucleus pulposus cells transduced with adenoviruses expressing BMP-2, 3, 4, 5, 7, 8, 10, 13, 15, and Sox9 accumulated more proteoglycans than nucleus pulposus cells transduced with adenovirus expressing green fluorescent protein (control). It is noteworthy that nucleus pulposus cells transduced with adenoviruses expressing BMP-2 and 7 resulted in essentially as great a stimulation of proteoglycan accumulation as nucleus pulposus cells maintained in the presence of rhBMP-7 (adenoviruses expressing BMP-2: 104% increase; adenoviruses expressing BMP-7: 162% increase; and rhBMP-7: 120% increase). Nucleus pulposus cells transduced with BMP-2, 4, 5, 7, 8, 10, 14, 15, and Sox9 accumulated significantly more collagen compared to nucleus pulposus cells transduced with adenovirus expressing green fluorescent protein; adenoviruses expressing BMP-4 and 14 were the most effective (552% and 661% increase, respectively). Nucleus pulposus cells also proliferated, as measured by deoxyribonucleic acid content, when transduced with adenoviruses expressing BMP-2 and 8. CONCLUSIONS: To our knowledge, for the first time, we have shown the relative effectiveness of 12 different BMPs and Sox9 in stimulating proteoglycan and collagen production by nucleus pulposus cells. Adenoviruses expressing BMP-2 and 7 were the most effective in stimulating proteoglycan accumulation, while adenoviruses expressing BMP-4 and 14 were the most effective in stimulating collagen accumulation. To our knowledge, this study is the first to compare the relative effectiveness of various BMPs and Sox9 on extracellular matrix accumulation by nucleus pulposus cells, and could help to develop more efficacious approaches to the treatment of degenerating intervertebral discs.

Adenoviridae↗

In vivo BMP-7 (OP-1) enhancement of osteoporotic vertebral bodies in an ovine model.

BACKGROUND CONTEXT: Prevention of osteoporotic vertebral fractures could help at-risk individuals avoid the pain and morbidity associated with these fractures. Currently, patients with osteoporosis are treated with systemic medications to reduce fracture risk. Although effective, these therapies do not eliminate fractures and also tend to have a gradual time-dependent effect on fracture risk. The mechanism of action of the bone morphogenetic protein (BMP) family theoretically makes these molecules candidates for rapidly enhancing local bone structure. STUDY DESIGN: An in vivo study analyzing the effects of BMP-7 (osteogenic protein 1 [OP-1]) treatment on osteopenic ovine vertebral architecture and biomechanics. PURPOSE: We tested the hypothesis that local injection of OP-1 into osteopenic ovine vertebrae will improve bone mass and trabecular distribution, thereby reducing bone fragility and fracture risk. We specifically evaluated compressive biomechanics and morphology of osteopenic ovine vertebral bodies 6 months after local OP-1 treatment. STUDY DESIGN: In vivo animal study. METHODS: Skeletally mature sheep (n=24) underwent ovariectomy and were placed on low cation relative to anion diet. These interventions reduce bone density and induce skeletal fragility. After 6 months, sheep were randomly assigned to six treatment groups based on OP-1 dose (370 mg or 0 mg) and carrier with 4 animals/treatment group. Carriers A and B were poly-L-glycolic acid (PLGA) biospheres with different release kinetics (B allowing sustained BMP release); Carrier C was carboxymethylcellulose. After creating an 8-mm-diameter defect in the midvertebral body, sheep underwent intravertebral body implantation at two nonadjacent levels. Animals were euthanized 6 months after implantation and bone mineral density (BMD), biomechanics, and histomorphometry were assessed. Two-way analysis of variance was used to determine effects of OP-1 (alpha=0.05). RESULTS: An 81.9%, 333.2%, and 39.9% increase in stiffness was seen for OP-1 treated vertebra with Carriers A, B, and C respectively. Although these effects did not reach statistical significance, trends toward improvement were evident. Histology showed varied degrees of bony healing in the injection sites. Histomorphometrically, OP-1 treated vertebrae showed improvements in percent bone of up to 38% and star volume of up to 55% (with Carrier B). Improvements in whole vertebral body BMD were not detected for any treatment. CONCLUSION: In this study, local OP-1 treatment showed a positive trend in improving mechanical strength and histomorphometric parameters of osteopenic vertebra, despite the absence of consistent change in BMD. Controlled slow release of OP-1 using PLGA microspheres appeared to be the most effective method of protein delivery. In conclusion, we feel that the pilot data suggest that the use of OP-1 in the treatment of vertebral osteoporosis in an attempt to enhance bone strength merits further study.

Acidosis↗

Transduced bovine articular chondrocytes affect the metabolism of cocultured nucleus pulposus cells in vitro: implications for chondrocyte transplantation into the intervertebral disc.

STUDY DESIGN: Biologic study on the effects of coculture of bovine articular chondrocytes transduced ex vivo with genes expressing bone morphogenetic proteins (BMPs) on nucleus pulposus (NP) cells. OBJECTIVE: To evaluate the effects of bovine articular chondrocytes transduced with adenoviruses expressing various BMPs on proteoglycan and collagen production, and cellular proliferation of NP cells in vitro. SUMMARY OF BACKGROUND DATA: Matrix synthesis by intervertebral disc cells is promoted by exposing the cells to growth factors or delivering genes that permit sustained expression of growth factors. We propose a novel therapeutic approach involving delivery of autologous chondrocytes, transduced ex vivo with bioactive proteins, to provide both the cells and proteins required to stimulate disc healing. METHODS: Adult bovine articular chondrocytes were transduced with adenoviruses (Ads) expressing either BMP-2, 4, 5, 7, 10, or 13 and plated as monolayers. Bovine NP cells encapsulated in alginate beads were cocultured, floating in the medium. Proteoglycan and collagen accumulation, and NP cell proliferation were measured after 6 days of coculture. As a positive control, beads were cocultured with articular chondrocytes in the presence of rhBMP-7. RESULTS: NP cells cocultered with articular chondrocytes transduced with BMPs-2, 4, 7, and 10 accumulated significantly (P < 0.05) more proteoglycan than when cocultured with chondrocytes transduced with AdGFP (control) [AdBMP-2: 23.6%; AdBMP-4: 27.0%; AdBMP-7: 129.1%; AdBMP-10: 102.1% increases respectively]. Collagen accumulation was significantly (P < 0.05) increased by NP cells cocultured with articular chondrocytes transduced with BMPs-2, 4, 5, and 7. [AdBMP-2: 104.6%; AdBMP-4: 40.6%; AdBMP-5: 58.6%; AdBMP-7: 55.5% increases respectively]. NP cells proliferated when cocultured with articular chondrocytes transduced with AdBMP-2 and -7. CONCLUSIONS: Bovine NP cells are stimulated to produce proteoglycans and collagen when exposed to chondrocytes transduced with genes for various BMPs. If applied to the treatment of disc degeneration, this strategy could provide the disc with not only metabolically active chondrocytes but also promote matrix replenishment by stimulating native NP cells.

Animals↗

A prospective, randomized, double-blind study evaluating the efficacy of postoperative continuous local anesthetic infusion at the iliac crest bone graft site after spinal arthrodesis.

STUDY DESIGN: Parallel design, prospective, double-blind, randomized, controlled trial composed of two independent groups treated with a continuous infusion catheter (saline vs. Marcaine) placed into the iliac crest bone graft (ICBG) site. OBJECTIVE: To determine the effects of postoperative continuous local anesthetic agent infusion at the ICBG harvest site in reducing pain, narcotic demand and usage, and improving early postoperative function after spinal fusion. SUMMARY OF BACKGROUND DATA: Harvesting iliac crest bone has been shown to be a source of pain and morbidity. Long-term patient complaints may be more closely associated with the procurement of the iliac crest graft rather than the primary surgical site. METHODS: Thirty-seven patients were enrolled in a prospective, randomized, double-blind parallel-designed study after informed consent and IRB approval was obtained. Twenty-eight patients had ICBG harvested for lumbar arthrodesis and nine for cervical arthrodesis. During spinal arthrodesis surgery, patients were randomly assigned to receive 96 mL (2 mL/hr x 48 hours) of either normal saline (control group, n = 22) or 0.5% Marcaine (treatment group, n = 15) delivered via a continuous infusion catheter placed at the ICBG harvest site. All patients received Dilaudid PCA after surgery. Pain scores, narcotic use/frequency, activity level, and length of stay (LOS) were recorded. Physicians, patients, nursing staff, and statisticians were blinded to the treatment. RESULTS: Mean patient age was 60 years and similar between groups. Narcotic dosage, demand frequency, and mean VAS pain score were significantly less in the treatment (Marcaine) group at 24 and 48 hours (P < 0.05). The average LOS was 4.1 days with no difference between Marcaine or control groups. No complications were attributed to the infusion-catheter system. CONCLUSIONS: Continuous infusion of 0.5% Marcaine at the ICBG harvest site reduced postoperative parenteral narcotic usage by 50% and decreased overall pain scores. No complications were attributed to the infusion-catheter system. The use of continuous local anesthetic infusion at the iliac crest may help in alleviating acute graft-related pain, hastening patient recovery and improving short-term satisfaction.

Adult↗

Cervical disc replacement.

STUDY DESIGN: Review article. OBJECTIVE: To critically review the state of the emerging field of cervical disc replacement. SUMMARY OF BACKGROUND DATA: Although anterior cervical decompression and fusion (ACDF) has been used successfully in the treatment of symptomatic radiculopathy and/or myelopathy, biomechanical studies have reported the deleterious effects of cervical fusion on adjacent level kinematics. Proponents of cervical disc replacement claim that maintenance of motion at the operated level will reduce the incidence of adjacent level degeneration and improve long-term clinical outcomes when compared with ACDF. METHODS: A systematic review of the literature dealing with cervical disc replacement and technologies of arthroplasty design that may have relevance to the cervical spine. A review of the design characteristics and published clinical data for cervical prostheses undergoing Investigational Device Exemption (IDE) study in the United States is provided. RESULTS: Current cervical disc replacement designs include one-piece implants and implants with single- or double-gliding articulations with either metal-on-metal or metal-on-polymer bearing surfaces. Reports of in vitro wear testing have claimed substantially less wear for cervical implants than that seen with prosthetic hips and knees. Short-term clinical results after decompression and cervical disc replacement for the treatment of cervical radiculopathy and/or myelopathy are encouraging. Prospective, randomized trials are lacking. CONCLUSIONS: Cervical disc replacement is an innovative technology that preserves motion at the instrumented level/s and will potentially improve load transfer to the adjacent levels compared with fusion. Clinical reports of success of cervical total disc replacement are encouraging but are also quite preliminary. As the U.S. IDE studies are completed, a clearer role for the place of cervical disc replacement in the spine surgeon's armamentarium should emerge.

Arthroplasty, Replacement↗

Open vertebral cement augmentation combined with lumbar decompression for the operative management of thoracolumbar stenosis secondary to osteoporotic burst fractures.

Osteoporotic burst fractures with neurologic symptoms are typically treated with neural decompression and multilevel instrumented fusion. These large surgical interventions are challenging because of patients' advanced ages, medical co-morbidities, and poor fixation secondary to osteoporosis. The purpose of this retrospective clinical study was to describe a novel technique for the treatment of osteoporotic burst fractures and symptomatic spinal stenosis via a limited thoracolumbar decompression with open cement augmentation [vertebroplasty (VP) or kyphoplasty (KP)]. Indications for decompression and cement augmentation were intractable pain at the level of a known osteoporotic burst fracture with symptoms of spinal stenosis. As such, 25 patients (mean age, 76.1 years) with low-energy, osteoporotic, thoracolumbar burst fractures (7 males, 18 females; 39 fractures) were included. In all cases, laminectomy of the stenotic level(s) was followed by vertebral cement augmentation (9 VP; 16 KP). When a spondylolisthesis at the decompressed level was present, instrumentation was applied across the listhetic level (n = 9). Clinical outcome (1 = poor to 4 = excellent) was assessed on last clinical follow-up (mean, 44.8 wks). In addition, a modified MacNab's grading criteria was used to objectively assess patient outcomes postoperatively. Radiographic analysis of sagittal contour was assessed preoperatively, immediately postoperatively, and at final follow-up. The average time from onset of symptoms to intervention was 19 weeks (range, 0.3-94 wks). A mean of 1.6 fractures/patient was augmented (range, 1-3 fractures) and 2.8 levels were decompressed (range, 1-6 levels). No statistical difference in anatomic distribution or number of fractures between the VP and KP groups or in the instrumented versus noninstrumented patients was noted (P > 0.05). An overall subjective outcome score of 3.4 was noted. Twenty of 25 patients were graded as excellent/good according to the modified MacNab's criteria. The choice of augmentation procedure or use of instrumentation did not predict outcome (P = 0.08). Overall, 1.7 degrees of sagittal correction was obtained at final follow-up. One patient was noted to have progressive kyphosis after KP. The use of a limited-posterior decompression and open cement augmentation via VP or KP is a safe treatment option for patients who have osteoporotic burst fractures and who are incapacitated from fracture pain and concomitant stenosis. After thoracolumbar decompression, open VP/KP provides direct visualization of the posterior vertebral body wall, allowing for safe cement augmentation of burst fractures, stabilizing the spine, and obviating the need for extensive spinal reconstruction. Although clinically successful, this technique warrants careful patient selection.

Aged↗

Minimally invasive spine surgery.

This article reviews the rationale, suggested benefits, and techniques of minimally invasive surgery (MIS) of the spine. While the efficacy and outcomes of open spinal decompression and fusion procedures have been validated in numerous longitudinal studies, these surgeries typically involve significant soft-tissue dissection and muscle retraction. MIS techniques aim to minimize iatrogenic damage to the soft tissues around the spine while allowing surgeons to perform effective decompression and fusion procedures. Here we summarize the rationale for the trend toward spinal MIS and highlight the more common procedures.

Arthrodesis↗

Effect of supplemental translaminar facet screw fixation on the stability of stand-alone anterior lumbar interbody fusion cages under physiologic compressive preloads.

STUDY DESIGN: A biomechanical study of lumbar threaded interbody cage construct under varying compressive preloads of similar magnitudes to those experienced in vivo during daily activities. OBJECTIVES: To test the hypothesis that supplemental translaminar facet screws would enhance the stability (ability to reduce segmental angular motion) of threaded interbody cages in flexion-extension during activities in which the spine is subjected to low compressive preloads, and therefore the stand-alone interbody cage construct is least stable. SUMMARY OF BACKGROUND DATA: Controversy exists over whether threaded anteriorly placed interbody cages can be routinely used as "stand-alone" devices or whether they require supplemental posterior stabilization to achieve successful fusion. Biomechanical studies suggest that under conditions of low preloads, the motion segment treated with stand-alone cages might be less stable, particularly in extension. METHODS.: Eight human lumbar spine specimens (from L1 to sacrum) were tested intact, after insertion of 2 threaded cylindrical cages (BAK) at L5-S1 and after supplemental translaminar facet screw fixation. They were subjected to flexion and extension moments under progressively increasing magnitude of externally applied compressive follower preload from 0 to 1200 N. The range of angular motion in flexion-extension at L5-S1 was analyzed to assess the effect of translaminar facet screws on the stability of the cage construct for different compressive preloads. RESULTS: In flexion, over 0 to 400 N preload, the supplemental translaminar facet screw fixation reduced the L5-S1 angular motion relative to intact by 71% to 74% as compared to 40% to 44% for the cages alone. This difference was statistically significant (P < 0.05). In extension at 0 N preload, the cages allowed more angular motion than the intact segment, whereas with translaminar facet screw fixation, the motion was reduced to the level of the intact segment. At 400 N preload, supplemental TLFS fixation significantly increased the stability of the cages, reducing the extension angular motion by 60% of intact (P = 0.04). Supplemental translaminar facet screw fixation did not significantly increase the stability provided by the cages in flexion or extension at the 1200 N preload magnitude. CONCLUSIONS: In vivo during activities of daily living, interbody cage constructs are subject to varying compressive preloads due to external loads generated by paraspinal musculature, and our results suggest that the stability created by the cage (reduction in segmental angular motion) is not constant. The cage construct is likely to be least stable in extension during activities that impart low compressive preloads to the lumbar spine. Supplemental translaminar facet screw fixation will enhance stability of the motion segment treated with threaded cages, particularly during conditions of low compressive preloads, the very condition in which the cage alone is least effective in providing stability.

Adult↗

Anatomical and pathological considerations in percutaneous vertebroplasty and kyphoplasty: a reappraisal of the vertebral venous system.

OBJECTIVES: To focus attention of the clinician on the anatomy and (patho)physiology of the vertebral venous system, so as to offer a tool to better understand and anticipate (potential) complications that are related to the application of percutaneous vertebroplasty and kyphoplasty. BACKGROUND: Percutaneous vertebroplasty and kyphoplasty are newly developed, minimally invasive techniques for the relief of pain and for the strengthening of bone in vertebral body lesions. With the clinical implementation of these techniques, a number of serious neurologic and cardiopulmonary complications have been reported in the international medical literature. Most complications appear to be related to the extrusion of bone cement into the vertebral venous system. METHODS: The literature about complications of percutaneous vertebroplasty and kyphoplasty is reviewed, and the anatomic and (patho)physiologic characteristics of the vertebral venous system are reported. Based on what is currently known from the anatomy and physiology of the vertebral venous system, the procedures of percutaneous vertebroplasty and kyphoplasty are analyzed, and suggestions are made to improve the safety of these techniques. CONCLUSIONS: Thorough knowledge of the anatomic and (patho)physiologic characteristics of the vertebral venous system is mandatory for all physicians that participate in percutaneous vertebroplasty and kyphoplasty. To reduce the risk of cement extrusion into the vertebral venous system during injection, vertebral venous pressure should be increased during surgery. This can be achieved by operating the patient in the prone position and by raising intrathoracic venous pressure with the aid of the anesthesiologist during intravertebral instrumentation and cement injection. Intensive theoretical and practical training, critical patient selection, and careful monitoring of the procedures, also taking into account patient positioning and intrathoracic and intra-abdominal pressures, will help to facilitate low morbidity outcomes in these very promising minimally invasive techniques.

Blood Pressure↗

Osteoporotic spinal deformity: a biomechanical rationale for the clinical consequences and treatment of vertebral body compression fractures.

This review article develops a biomechanical rationale for the clinical consequences and treatment of osteoporotic vertebral body compression fracture. In patients with osteoporotic vertebral fractures and spinal deformity, altered spinal biomechanics and global spinal imbalance are important factors in the increased morbidity and mortality reported in this population. Severe spinal deformity impairs physical functioning, health, and quality of life. The spinal deformity itself, independent of pain, is a significant cause of disability. Spinal deformity is also an independent risk factor for hip fracture. Treatments directed at osteoporotic vertebral compression fractures should ideally address spinal deformity as well as pain. Balloon kyphoplasty, the minimally invasive technique of reduction and internal fixation of osteopenic vertebral body compression fractures that addresses pain and spinal deformity, is discussed.

Biomechanical Phenomena↗

Early radiographic and clinical results of balloon kyphoplasty for the treatment of osteoporotic vertebral compression fractures.

STUDY DESIGN: A prospective consecutive cohort study of clinical and radiographic outcomes after kyphoplasty for treatment of osteoporotic vertebral compression fractures. OBJECTIVES: To measure changes in spinal deformity, activity level, and pain after kyphoplasty treatment. SUMMARY OF BACKGROUND DATA: Pain and kyphosis caused by osteoporotic vertebral compression fractures adversely affect quality of life and survival. Kyphoplasty involves the inflation of a balloon bone tamp, percutaneously placed in a fractured vertebral body, followed by deposition of bone cement into the resulting cavity. Previous reports indicate that kyphoplasty improves patient function and restores height of collapsed vertebral bodies, but limited data about the effects of kyphoplasty on spinal sagittal alignment are available. METHODS: Twenty-nine patients with osteoporotic vertebral compression fractures who did not respond to medical therapy were treated by kyphoplasty. These patients underwent 37 operations to treat 61 vertebral compression fractures between T6 and L5. Sagittal alignment was analyzed from standing radiographs (pre- and postkyphoplasty). Patient surveys were used to assess pain relief, improvement in activity, and satisfaction with the surgical procedure. RESULTS: In this cohort, a mean of 8.8 degrees (range 0-29 degrees ) of correction of local spinal kyphosis was achieved with kyphoplasty. Thirty of 52 fractures (17 patients) were considered reducible and had >5 degrees of correction, with a mean improvement in sagittal alignment of this population of 14.2 degrees. Patient surveys revealed significant pain reduction within the first week after surgery and improved activity levels for a majority of patients. CONCLUSIONS: Kyphoplasty improves physical function, reduces pain, and may correct kyphotic deformity associated with vertebral compression fractures.

Aged↗

Interbody cage devices.

STUDY DESIGN: A literature review was conducted of basic science research and clinical experiences describing the use of interbody cage devices for the management of degenerative spinal abnormalities. OBJECTIVES: To summarize current knowledge regarding the use of interbody fusion cages. SUMMARY OF BACKGROUND DATA: Degenerative conditions of the lumbar and cervical spine are a major societal expense and a leading cause of disability. Fusion surgery may be used to treat patients with some of these conditions. During the past decade, interbody cages have been popularized as a useful fusion technique with high rates of clinical and radiographic success reported. Cages may be implanted using a variety of surgical approaches to the disc space and can be used alone or with supplemental posterior fixation. METHODS: A literature review of biomechanical, biologic, and clinical studies of threaded interbody cages was performed. RESULTS: Interbody cages have been shown to successfully promote fusion in a variety of animal models. In biomechanical studies, anteriorly placed threaded cages significantly stabilize the motion segment in all directions except extension. Posteriorly placed cages provide less stability as a result of the facetectomy required for placement of an appropriately sized device. Successful clinical and radiographic results have been reported with the use of interbody cages. Most reported cage failures are the result of technical difficulties with implantation or poor patient selection. Accurate radiographic assessment of fusion in the presence of a metal interbody cage remains challenging, and studies evaluating alternate biomaterial cages are underway. CONCLUSION: Interbody cages are a useful technique for achieving spinal fusion and have been shown to have an acceptable clinical success rate in appropriately selected patients.

Animals↗

Minimally invasive fusion: summary statement.

Ideally, minimally invasive surgery (MIS) allows less extensive manipulation of surrounding tissues than a conventional open procedure while accomplishing the same goals and objectives at the target structure. Long-term follow-up combined with appropriate outcome measures are necessary to prove the safety and effectiveness of MIS. For MIS procedures to be widely adopted, they must have an acceptable learning curve. Special skills are needed and are beyond those of traditional open surgery, By definition, as compared with conventional open surgeries, minimally invasive procedures typically involve smaller incisions and less extensive surgical manipulation of the tissues that surround the target structure. Ideally, once the target structure has been reached, the minimally invasive procedure should accomplish the same goals and objectives as its open surgical counterpart. Thus, although minimally invasive surgeries are aimed at reducing the morbidity associated with open surgical approaches, they should not hinder the surgeon's ability to perform a successful operation. In other words, minimal invasion should not equate to minimally effective.

Clinical Competence↗

Minimally invasive treatments of osteoporotic vertebral compression fractures.

STUDY DESIGN: A literature review of experiences with vertebroplasty and kyphoplasty for treating symptomatic, osteoporotic vertebral compression fractures (VCFs). OBJECTIVES: To summarize the advantages and disadvantages of kyphoplasty and vertebroplasty. SUMMARY OF BACKGROUND DATA: Osteoporotic VCFs are a leading cause of disability and morbidity in the elderly. The consequences of osteoporotic VCFs (pain and often progressive vertebral collapse with resultant spinal kyphosis) adversely affect quality of life, physical function, mental health, and survival. Vertebroplasty and kyphoplasty are minimally invasive procedures for treating painful fractures. Vertebroplasty entails the percutaneous injection of bone cement into the fractured vertebra in attempts to stabilize the fracture and reduce pain. Kyphoplasty addresses pain and kyphotic deformity by the percutaneous expansion of an inflatable bone tamp to effect fracture reduction before cement deposition in a fractured vertebra. METHODS: A literature review of surgical techniques, indications, clinical results, and complications for vertebroplasty and kyphoplasty. RESULTS: Studies of vertebroplasty and kyphoplasty have reported excellent pain relief and improved function in most patients with osteoporotic VCFs. Vertebroplasty has the advantage of being relatively quick and inexpensive. Kyphoplasty, while associated with increased cost and surgical time, offers the potential to improve spinal alignment. In addition, by creating an intravertebral cavity, kyphoplasty reduces the risk of extravertebral bone filler extravasation. CONCLUSIONS: Vertebroplasty and kyphoplasty are currently used to treat osteoporotic VCFs with successful short-term results. Prospective, randomized studies comparing these procedures to one another and comparing their long-term outcomes to conventional medical management are required to define precise roles of these exciting treatments in the spine physician's armamentarium.

Bone Cements↗