Posterior Lateral Arthrodesis as a Treatment Option for Lumbar Spinal Stenosis: Safety and Early Clinical Outcomes.

Introduction: Lumbar spinal stenosis (LSS) is a common condition caused by degenerative changes in the lumbar spine with age. LSS is caused by a variety of factors, including degenerative spondylosis and spondylolisthesis. People suffering with LSS experience neurogenic claudication, which causes severe physical limitations, discomfort, and a decrease in quality of life. Less invasive procedures are now being researched to improve the prognosis, success rate, and safety of LSS treatments. Posterior lateral spinal arthrodesis (PLSA) is a new surgical treatment for LSS. This study looks at the procedural and patient safety of PLSA. Materials and methods: This study is a multicenter retrospective analysis of the safety of PLSA who met the clinical indications for PLSA and underwent the procedure at eight interventional spine practices. Data was collected on demographical information, pre-procedural numeric rating scale score (NRS), post-procedural NRS, and complication reporting. Patients who were included had LSS with or without spondylolisthesis and had failed conservative treatments. A descriptive statistical analysis was performed to report the outcomes. Results were reported as mean and standard deviations for continuous outcomes, and frequency (%) for categorical outcomes. Results: This retrospective analysis involved 191 patients and 202 PLSA implants. The majority of patients were male Caucasians with a mean age of 69.2 years and a BMI of 31.1. A large majority of implants were placed at the L4-5 level, and the average pre-procedural NRS was 6.3 while the average post-procedural NRS was 3.1, indicating a 50.8% reduction in pain (p < 0.0001). Two patients reported complications, but they were unrelated to the device or surgical procedure; no infections, device malfunctions, or migrations were reported in the patient cohort. Conclusion: Preliminary results with PLSA implants indicate that it is a safe treatment option for patients with moderate LSS who do not respond to conservative management.

Clinical and Radiographic Outcomes After Minimally Invasive Transforaminal Lumbar Interbody Fusion-Early Experience Using a Biplanar Expandable Cage for Lumbar Spondylolisthesis.

BACKGROUND: Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) is a surgical technique frequently used to treat symptomatic lumbar spondylolisthesis. We aim to investigate the safety and efficacy of using a biplanar expandable cage in the treatment of symptomatic lumbar spondylolisthesis using a MIS TLIF approach. METHODS: A retrospective review of patient records was performed on patients who underwent MIS TLIF for symptomatic lumbar spondylolisthesis using the FlareHawk cage over a 12-month period. Patient demographics, as well as preoperative and postoperative clinical and radiographic outcome measures were recorded and analyzed. RESULTS: A total of 13 consecutive patients underwent MIS TLIF for symptomatic spondylolisthesis during the study period. The mean age was 60.2 ± 13.9 years, and 61.5% were female. The mean preoperative and postoperative slippage was 7.0 ± 3.0 mm and 1.0 ± 1.9 mm, respectively. The preoperative mean segmental lordosis was 5.1° ± 6.0°, mean anterior, posterior disc, and foraminal height were 9.1 ± 3.9 mm, 5.7 ± 1.5 mm, and 11.0 ± 2.0 mm, respectively. The postoperative mean segmental lordosis was 6.8° ± 4.7°, and mean anterior, posterior disc, and foraminal height were 11.4 ± 2.2 mm, 7.8 ± 1.0 mm, and 12.3 ± 1.3 mm. There was improvement in all radiographic parameters postoperatively. The mean Visual Analog Scale (VAS) back pain, VAS leg pain improved from 7.0 ± 2.9 and 5.1 ± 3.0 preoperatively to 3.1 ± 2.9 and 1.1 ± 1.7 at the latest clinic follow-up visit, respectively (P = .0081). The mean EuroQol-Five Dimensions (EQ5D) score improved from 0.37 ± 1.7 to 0.66 ± 0.23 after surgery. There was no subsidence, endplate violation, cage migration, or other implant-related complications. No patient required reoperation. CONCLUSIONS: The biplanar expandable cage is both safe and efficacious in treating symptomatic lumbar spondylolisthesis using the MIS TLIF approach. Spine surgeons should be familiar with the biplanar expandable cage technology and keep it in their armamentarium in surgical treatment of lumbar spondylolisthesis. LEVEL OF EVIDENCE: 4.

A cadaveric precision and accuracy analysis of augmented reality-mediated percutaneous pedicle implant insertion.

OBJECTIVE: Augmented reality-mediated spine surgery (ARMSS) is a minimally invasive novel technology that has the potential to increase the efficiency, accuracy, and safety of conventional percutaneous pedicle screw insertion methods. Visual 3D spinal anatomical and 2D navigation images are directly projected onto the operator's retina and superimposed over the surgical field, eliminating field of vision and attention shift to a remote display. The objective of this cadaveric study was to assess the accuracy and precision of percutaneous ARMSS pedicle implant insertion. METHODS: Instrumentation was placed in 5 cadaveric torsos via ARMSS with the xvision augmented reality head-mounted display (AR-HMD) platform at levels ranging from T5 to S1 for a total of 113 total implants (93 pedicle screws and 20 Jamshidi needles). Postprocedural CT scans were graded by two independent neuroradiologists using the Gertzbein-Robbins scale (grades A-E) for clinical accuracy. Technical precision was calculated using superimposition analysis employing the Medical Image Interaction Toolkit to yield angular trajectory (°) and linear screw tip (mm) deviation from the virtual pedicle screw position compared with the actual pedicle screw position on postprocedural CT imaging. RESULTS: The overall implant insertion clinical accuracy achieved was 99.1%. Lumbosacral and thoracic clinical accuracies were 100% and 98.2%, respectively. Specifically, among all implants inserted, 112 were noted to be Gertzbein-Robbins grade A or B (99.12%), with only 1 medial Gertzbein-Robbins grade C breach (> 2-mm pedicle breach) in a thoracic pedicle at T9. Precision analysis of the inserted pedicle screws yielded a mean screw tip linear deviation of 1.98 mm (99% CI 1.74-2.22 mm) and a mean angular error of 1.29° (99% CI 1.11°-1.46°) from the projected trajectory. These data compare favorably with data from existing navigation platforms and regulatory precision requirements mandating that linear and angular deviation be less than 3 mm (p < 0.01) and 3° (p < 0.01), respectively. CONCLUSIONS: Percutaneous ARMSS pedicle implant insertion is a technically feasible, accurate, and highly precise method.

Cytokines in umbilical cord blood-derived cellular product: a mechanistic insight into bone repair.

AIM: Umbilical cord blood (UCB) finds frequent applications in regenerative medicine. We evaluated the role of cytokines present in a uniquely processed, UCB-derived cellular allograft product (UCBp). MATERIALS & METHODS: Luminex multiplex assay and standard cell biology methods were employed. RESULTS: Study with allografts from 33 donors identified 44 quantifiable cytokines in the UCBp derived conditioned media (CM). The UCBp-CM elevated proliferation and migration rates of mesenchymal stem cells (MSCs) and bone marrow stromal cells. Moreover, UCBp-CM induced secretion of VEGF-A and osteoprotegerin, which promoted angiogenesis of endothelial cells and positively influenced the osteogenic differentiation of MSCs, respectively. CONCLUSION: Cytokines in UCBp stimulate cellular processes important for bone regeneration, making UCBp an excellent candidate for potential applications in orthopedic procedures like bone non-union and spinal fusion.

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF): surgical technique, long-term 4-year prospective outcomes, and complications compared with an open TLIF cohort.

Transforaminal lumbar interbody fusion (TLIF) is an important surgical option for the treatment of back pain and radiculopathy. The minimally invasive TLIF (MI-TLIF) technique is increasingly used to achieve neural element decompression, restoration of segmental alignment and lordosis, and bony fusion. This article reviews the surgical technique, outcomes, and complications in a series of 144 consecutive 1- and 2-level MI-TLIFs in comparison with an institutional control group of 54 open traditional TLIF procedures with a mean of 46 months' follow-up. The evidence base suggests that MI-TLIF can be performed safely with excellent long-term outcomes.

Minimally invasive lateral extracavitary corpectomy: cadaveric evaluation model and report of 3 clinical cases.

OBJECT: In this paper, the authors' goal was to demonstrate the clinical and technical nuances of a minimally invasive lateral extracavitary approach (MI-LECA) for thoracic corpectomy and anterior column reconstruction. METHODS: A cadaveric feasibility study and the subsequent application of this approach in 3 clinical cases are reported. Six procedures were completed in 3 human cadavers. Minimally invasive, extrapleural thoracic corpectomies were performed with the aid of a 24-mm tubular retraction system, using a posterolateral incision and an oblique approach angle. Fluoroscopy and postprocedural CT scanning, using 3D volumetric averaging software, was used to evaluate the degree of bone removal and decompression. Three clinical cases, including a T-11 burst fracture, a T-7 plasmacytoma, and a T4-5 vertebral body (VB) tuberculosis lesion, were treated using the approach. RESULTS: At 6 cadaveric levels, the mean circumferential volumetric decompression was 48% ± 16%, and the mean resection of the VB was 72% ± 13%. The mean change in anterior and posterior vertebral height with expansion of the corpectomy cage was 47 and 61 mm, respectively. There were no violations of the pleura or dura. Pedicle screw reliability was 95.8% (23 of 24 screws) with a single lateral breach. All 3 patients in the clinical cohort had excellent clinical outcomes. There was a single pleural tear requiring chest tube drainage. Operative images and a video clip are provided to illustrate the approach. CONCLUSIONS: A minimally invasive lateral extracavitary thoracic corpectomy has the ability to provided excellent spinal cord decompression and VB resection. The procedure can be completed safely and successfully with minimal blood loss and little associated morbidity. This approach has the potential to improve upon established traditional open corridors for posterolateral thoracic corpectomy.

Somatosensory-evoked potential asymmetry in medullary ischemia during cervical spine surgery.

This report describes how somatosensory-evoked potentials (SEPs) can detect acute medullary ischemia during cervical spine surgery. This article describes how asymmetric SEP intraoperative monitoring changes can localize medullary ischemia. Localization of change was validated by postoperative magnetic resonance imaging (MRI). A 68-year-old man underwent cervical posterior fusion with monitoring of bilateral SEPs of the upper and lower extremities. The SEPs disappeared during initial exposure of the C1 lamina. Changes were asymmetric in degree and duration. Brain MRI postoperatively demonstrated bilateral posterior inferior cerebellar artery (PICA) territory infarcts involving the left lateral medulla. This illustrates how intraoperative SEP monitoring can provide important information on the functional integrity of brainstem structures even during cervical surgery. A knowledge of medullary anatomy and vascular territories is necessary for interpreting SEP changes. In cervical surgery, SEPs incidentally monitor the integrity of the brainstem while monitoring the spinal cord. The asymmetry of SEP change seen here was consistent with medullary level impairment, where the vascular territory is lateralized in contrast to the symmetric anterior spinal artery territory.

Emerging techniques in the minimally invasive treatment and management of thoracic spine tumors.

Over the past decade, the development and refinement of minimally invasive spine surgery techniques has lead to procedures with the potential to minimize iatrogenic and post-operative sequelae that may occur during the surgical treatment of various pathologies. In a similar manner, parallel advances in other current treatment technologies have led to the development of other minimally invasive treatments of spinal malignancies. These advances include percutaneous techniques for vertebral reconstruction, including vertebroplasty and kyphoplasty, the development of safe and effective spinal radiosurgery, and minimal-access spinal surgical procedures that allow surgeons to safely decompress and reconstruct the anterior spinal column. The advent of these new techniques has given modern practitioners treatment options in situations where they previously were limited by the potentially significant morbidities of the available techniques. Here, the authors discuss the application of current minimally invasive technologies in the treatment of malignancies of the thoracic spine, focusing on vertebral kyphoplasty, spinal radiosurgery, and minimally invasive spinal decompression techniques. The author's describe how these emerging treatment options are significantly expanding the options open to clinicians in the treatment of thoracic spinal column malignancies. Specific illustrative case examples are provided. The development of these techniques has the potential to improve clinical outcomes, limit surgical morbidity, and also improve the safety and efficiency of treatment pathways.

A minimally invasive technique for percutaneous lumbar facet augmentation: Technical description of a novel device.

BACKGROUND: We describe a new posterior dynamic stabilizing system that can be used to augment the mechanics of the degenerating lumbar segment. The mechanism of this system differs from other previously described surgical techniques that have been designed to augment lumbar biomechanics. The implant and technique we describe is an extension-limiting one, and it is designed to support and cushion the facet complex. Furthermore, it is inserted through an entirely percutaneous technique. The purpose of this technical note is to demonstrate a novel posterior surgical approach for the treatment of lumbar degenerative. METHODS: This report describes a novel, percutaneously placed, posterior dynamic stabilization system as an alternative option to treat lumbar degenerative disk disease with and without lumbar spinal stenosis. The system does not require a midline soft-tissue dissection, nor subperiosteal dissection, and is a truly minimally invasive means for posterior augmentation of the functional facet complex. This system can be implanted as a stand-alone procedure or in conjunction with decompression procedures. RESULTS: One-year clinical results in nine individual patients, all treated for degenerative disease of the lower lumbar spine, are presented. CONCLUSIONS: This novel technique allows for percutaneous posterior dynamic stabilization of the lumbar facet complex. The use of this procedure may allow a less invasive alternative to traditional approaches to the lumbar spine as well as an alternative to other newly developed posterior dynamic stabilization systems.

Sacral laminoplasty and cystic fenestration in the treatment of symptomatic sacral perineural (Tarlov) cysts: Technical case report.

BACKGROUND: Perineural cysts of the sacrum, or Tarlov cysts, are cerebrospinal fluid (CSF)-filled sacs that commonly occur at the intersection of the dorsal root ganglion and posterior nerve root in the lumbosacral spine. Although often asymptomatic, these cysts have the potential to produce significant symptoms, including pain, weakness, and/or bowel or bladder incontinence. We present a case in which the sacral roof is removed and reconstructed via plated laminoplasty and describe how this technique could be of potential use in maximizing outcomes. METHODS: We describe technical aspects of a sacral laminoplasty in conjunction with cyst fenestration for a symptomatic sacral perineural cyst in a 50-year-old female with severe sacral pain, lumbosacral radiculopathy, and progressive incontinence. This patient had magnetic resonance imaging (MRI) and computed tomography (CT)-myelographic evidence of a non-filling, 1.7 × 1.4 cm perineural cyst that was causing significant compression of the cauda equina and sacral nerve roots. This surgical technique was also employed in a total of 18 patients for symptomatic tarlov cysts with their radiographic and clinical results followed in a prospective fashion. RESULTS: Intraoperative images, drawings, and video are presented to demonstrate both the technical aspects of this technique and the regional anatomy. Postoperative MRI scan demonstrated complete removal of the Tarlov cyst. The patient's symptoms improved dramatically and she regained normal bladder function. There was no evidence of radiographic recurrence at 12 months. At an average 16 month followup interval 10/18 patients had significant relief with mild or no residual complaints, 3/18 reported relief but had persistent coccydynia around the surgical area, 2/18 had primary relief but developed new low back pain and/or lumbar radiculopathy, 2/18 remained at their preoperative level of symptoms, and 1/18 had relief of their preoperative leg pain but developed new pain and neurological deficits. CONCLUSIONS: Sacral laminoplasty and microscopic cystic fenestration is a feasible approach in the operative treatment of this difficult, and often controversial, spinal pathology. This technique may be used further and studied in an attempt to minimize potential surgical morbidity, including CSF leaks, cyst recurrence, and sacral insufficiency fractures.

Ossification of the posterior longitudinal ligament: pathogenesis, management, and current surgical approaches. A review.

Ossification of the posterior longitudinal ligament (OPLL) is an important cause of cervical myelopathy that results from bony ossification of the cervical or thoracic posterior longitudinal ligament (PLL). It has been estimated that nearly 25% of patients with cervical myelopathy will have features of OPLL. Patients commonly present in their mid-40s or 50s with clinical evidence of myelopathy. On MR and CT imaging, this can be seen as areas of ossification that commonly coalesce behind the cervical vertebral bodies, leading to direct ventral compression of the cord. While MR imaging will commonly demonstrate associated changes in the soft tissue, CT scanning will better define areas of ossification. This can also provide the clinician with evidence of possible dural ossification. The surgical management of OPLL remains a challenge to spine surgeons. Surgical alternatives include anterior, posterior, or circumferential decompression and/or stabilization. Anterior cervical stabilization options include cervical corpectomy or multilevel anterior cervical corpectomy and fusion, while posterior stabilization approaches include instrumented or noninstrumented fusion or laminoplasty. Each of these approaches has distinct advantages and disadvantages. While anterior approaches may provide more direct decompression and best improve myelopathy scores, there is soft-tissue morbidity associated with the anterior approach. Posterior approaches, including laminectomy and fusion and laminoplasty, may be well tolerated in older patients. However, there often is associated axial neck pain and less improvement in myelopathy scores. In this review, the authors discuss the epidemiology, imaging findings, and clinical presentation of OPLL. The authors additionally discuss the merits of the different surgical techniques in the management of this challenging disease.

Comparison of three posterior dynamic stabilization devices.

STUDY DESIGN: A biomechanical study using human cadaveric lumbar spinal motion segments and three different posterior stabilization devices. OBJECTIVE: To compare the range of motion, disc height, and foraminal area of a spinal motion segment intact, injured, and fixed with each of three posterior lumbar motion preservation devices. SUMMARY OF BACKGROUND DATA: Motion-sparing lumbar posterior dynamic stabilization devices are gaining increasing popularity, particularly for the treatment of degenerative disc disease. METHODS: The PercuDyn, the X-Stop, and the Isobar posterior stabilization devices were compared using an in vitro cadaveric model. First, pure moments of ±8 Nm were applied in all three planes, then a follower load of 700 N was applied, and finally, sagittal bending tests were repeated. All tests were conducted using an 8-df servohydraulic load frame. Experiments were performed intact, with a simulated injury, and then with each of the three devices for a total of four specimens per device. Foraminal area and disc height (posterolateral and anterior surface) were measured under neutral and peak torques in all three planes and range of motion was recorded for all experimental conditions. RESULTS: Overall, the injury model successfully increased range of motion and decreased disc height and foraminal area. Once treated with one of the three implants, the PercuDyn was most effective at preventing hyperextension, decreasing extension with a follower load by a mean of 52% compared to injured conditions (P = 0.07). The X-Stop stabilized the posterior column, increasing foraminal area under all conditions, particularly extension with a follower load, by 27% compared to injured conditions (P = 0.01). The Isobar, the only device to stabilize the anterior column, increased anterior disc height under flexion with a follower load by 22% (P = 0.03). CONCLUSION: All three devices functioned as intended by their respective manufacturers, but each appeared to excel in different areas; therefore, each should be used for unique clinical applications.

Minimally invasive extracavitary approach for thoracic discectomy and interbody fusion: 1-year clinical and radiographic outcomes in 13 patients compared with a cohort of traditional anterior transthoracic approaches.

OBJECT: Open transthoracic approaches, considered the standard in treating thoracic disc herniation (TDH), are associated with significant comorbidities. The authors describe a minimally invasive lateral extracavitary tubular approach for discectomy and fusion (MIECTDF) to treat TDH. METHODS: In 13 patients (5 men, 8 women; mean age 51.8 years) with myelopathy and 15 noncalcified TDHs, the authors achieved a far-lateral trajectory by dilating percutaneously to a 20-mm working portal docked at the transverse process-facet junction, which then provided a corridor for a near-total discectomy, bilateral laminotomies, and interbody arthrodesis requiring minimal cord retraction. A cohort of 11 demographically comparable patients treated via transthoracic approaches was used as control. RESULTS: Preoperative Frankel grades were B in 1 patient, C in 4, D in 5, and E in 3, whereas at mean of 10 months, 11 had Grade E function and 2 had Grade D function. Mean surgical metrics were operating room time 93.75 minutes, blood loss 33 ml, and hospital stay 3.1 days. Complications included 4 transient paresthesias, 1 CSF leak, 1 abdominal wall weakness, and 3 nonwound infections. One-year follow-up MR imaging revealed full decompression in all cases and no cage migration. Mean visual analog scales scores preoperative, at 6 weeks, 3 months, and 1 year were 5.6, 4.5, 3.2, and 1.2, respectively. No differences existed in preoperative clinical and radiographic profile of the study and control groups. Compared with controls, the MIECTDF group achieved superior scores in all metrics (p < 0.01) except for equivalent 1-year neurological outcomes. CONCLUSIONS: Compared with transthoracic procedures, MIECTDF effectively decompressed the spinal canal, yielding identical 1-year radiographic and clinical outcomes to those seen in controls, while producing superior clinical scores in the interim. Thus, MIECTDF is the authors' treatment of choice for TDH.

Minimally invasive percutaneous transpedicular screw fixation: increased accuracy and reduced radiation exposure by means of a novel electromagnetic navigation system.

BACKGROUND: Minimally invasive percutaneous pedicle screw instrumentation methods may increase the need for intraoperative fluoroscopy, resulting in excessive radiation exposure for the patient, surgeon, and support staff. Electromagnetic field (EMF)-based navigation may aid more accurate placement of percutaneous pedicle screws while reducing fluoroscopic exposure. We compared the accuracy, time of insertion, and radiation exposure of EMF with traditional fluoroscopic percutaneous pedicle screw placement. METHODS: Minimally invasive pedicle screw placement in T8 to S1 pedicles of eight fresh-frozen human cadaveric torsos was guided with EMF or standard fluoroscopy. Set-up, insertion, and fluoroscopic times and radiation exposure and accuracy (measured with post-procedural computed tomography) were analyzed in each group. RESULTS: Sixty-two pedicle screws were placed under fluoroscopic guidance and 60 under EMF guidance. Ideal trajectories were achieved more frequently with EMF over all segments (62.7% vs. 40%; p = 0.01). Greatest EMF accuracy was achieved in the lumbar spine, with significant improvements in both ideal trajectory and reduction of pedicle breaches over fluoroscopically guided placement (64.9% vs. 40%, p = 0.03, and 16.2% vs. 42.5%, p = 0.01, respectively). Fluoroscopy time was reduced 77% with the use of EMF (22 s vs. 5 s per level; p < 0.0001) over all spinal segments. Radiation exposure at the hand and body was reduced 60% (p = 0.058) and 32% (p = 0.073), respectively. Time for insertion did not vary between the two techniques. CONCLUSIONS: Minimally invasive pedicle screw placement with the aid of EMF image guidance reduces fluoroscopy time and increases placement accuracy when compared with traditional fluoroscopic guidance while adding no additional time to the procedure.

Anatomical considerations for subaxial (C2) pedicle screw placement: a radiographic study with computed tomography in 93 patients.

STUDY DESIGN: Radiographic study. OBJECTIVE: More detailed anatomical knowledge of the C2 pedicle is required to optimize and minimize the risk of screw placement. The aim of this study was to evaluate the linear and angular dimensions of the true C2 pedicle using axial computed tomography. BACKGROUND DATA: Although earlier studies have analyzed the anatomy of the C2 pars interarticularis, little attention has been focused on the dimensions of the C2 pedicle. METHODS: Ninety-three patients (47 males, 46 females; mean age 48.4 y) who had previous cervical spinal computed tomography imaging were evaluated for this study. Axial images of the C2 pedicle were selected and the following pedicle parameters were determined: pedicle width (the mediolateral diameter of the pedicle isthmus, perpendicular to the pedicle axis) and pedicle transverse angle (PTA, ie, the angle between the pedicle axis and the midline of the vertebral body). RESULTS: The overall mean pedicle width was 5.8+/-1.2 mm. The mean pedicle width in male patients (6.0+/-1.3 mm) was greater than that in the female patients (5.6+/-1.1 mm). This difference was not found to be statistically significant (P=0.679). The overall mean PTA was 43.9+/-3.9 degrees. The mean PTA in male patients was 43.2+/-3.8 degrees, whereas that in female patients was 44.7+/-3.7 degrees. CONCLUSIONS: Given the significant variability in pedicle widths and the need for precise trajectory planning in pedicle cannulation, preoperative planning is absolutely mandatory. A significant percentage of patients have pedicle widths that may not accommodate screw fixation. In addition, the angle of entry into the C2 pedicle must be carefully measured for safe instrumentation at this level.

Primary bony non-Hodgkin lymphoma of the cervical spine: a case report.

INTRODUCTION: Non-Hodgkin lymphoma primarily originating from the bone is exceedingly rare. To our knowledge, this is the first report of primary bone lymphoma presenting with progressive cord compression from an origin in the cervical spine. Herein, we discuss the unusual location in this case, the presenting symptoms, and the management of this disease. CASE PRESENTATION: We report on a 23-year-old Caucasian-American man who presented with two months of night sweats, fatigue, parasthesias, and progressive weakness that had progressed to near quadriplegia. Magnetic resonance (MR) imaging demonstrated significant cord compression seen primarily at C7. Surgical management, with corpectomy and dorsal segmental fusion, in combination with adjuvant chemotherapy and radiation therapy, halted the progression of the primary disease and preserved neurological function. Histological analysis demonstrated an aggressive anaplastic large cell lymphoma. CONCLUSION: Isolated primary bony lymphoma of the spine is exceedingly rare. As in our case, the initial symptoms may be the result of progressive cervical cord compression. Anterior corpectomy with posterolateral decompression and fusion succeeded in preventing progressive neurologic decline and maintaining quality of life. The reader should be aware of the unique presentation of this disease and that surgical management is a successful treatment strategy.

Combined anterior C2-C3 fusion and C2 pedicle screw fixation for the treatment of unstable hangman's fracture: a contrast to anterior approach only.

STUDY DESIGN: A retrospective clinical study was used to evaluate the effect of a new surgical treatment of the hangman's fractures. OBJECTIVE: To determine the treatment efficacy of combined anterior C2-C3 reduction and fusion and posterior compressive C2 pedicle screw fixation for the management of unstable hangman's fractures. SUMMARY OF BACKGROUND DATA: The classification of hangman's fractures as proposed by Levine-Edwards was used to classify and guide the treatment of these injuries. Most of these fractures respond to a variety of conservative therapies, but recently, earlier surgery has been increasingly advocated by authors from several countries for the rapid stabilization of these fractures. If surgery is indicated, an anterior approach using a C2-C3 reduction and fusion is preferred usually. Another well-accepted surgical method is the direct transpedicular osteosynthesis by the dorsal approach. However, there was rare report of the combined use of these 2 techniques. METHODS: A group of 45 surgical patients were all diagnosed with radiograph, magnetic resonance imaging (MRI), and 3D CT scans. Initial and final radiographs were measured for anterior translation and angulation of the C2-C3 complex. Initial external skull traction with extension was used in all patients after admission to reduce the fracture. Then an anterior C2-C3 discectomy followed by an interbody fusion and locking plate fixation was performed. Intraoperative reduction was confirmed by fluoroscopic control. About 29 patients therefore received anterior surgeries only since satisfactory reduction was achieved during the procedure. For the 16 patients who had persistent large residual gaps after the anterior procedure, additional same stage posterior C2 compressive pedicle screws were placed. Clinical and radiologic comparisons were performed in these 2 groups. RESULTS: The follow-up ranged from 24 to 54 months, with an average 33.6 months. There was radiographic evidence of continuity of the fracture and the bone graft seen at 4.7 months on average. Neck pain and neurologic deficits resolved in nearly all patients after surgery. The anterior translation of anterior-posterior surgery group decreased more significant compared to anterior surgery group, although with no statistical significance. The fractures were closed with a slight gap no more than 2 mm in anterior-posterior surgery group. The residual kyphosis in anterior-posterior surgery group was still a little larger than it in anterior surgery group. No internal fixation failures or infections were observed. CONCLUSION: We believe that the need for single stage 360° fusion of hangman's fractures can be somewhat predicted by a combination of high resolution imaging. For hangman's fractures with significant deformity and gapping, it is our experience that immediate single-stage anterior-posterior reduction, instrumentation, and arthrodesis achieve superior postoperative reduction and long-term functional outcomes.

A Comparison of fixed-hole and slotted-hole dynamic plates for anterior cervical discectomy and fusion.

STUDY DESIGN: A retrospective review of clinical data at 1 institution was performed. OBJECTIVES: To compare the clinical and radiologic outcomes between fixed-hole and slotted-hole dynamic cervical plates. SUMMARY OF BACKGROUND DATA: Anterior cervical plating is commonly used to increase stability and promote spinal fusion. Two techniques, fixed-hole dynamic plating that uses variable angled screws and slotted-hole dynamic plating that permits sliding, are viable options, but there have been no clinical studies comparing their effectiveness. METHODS: Fifty-six patients at 1 institution having anterior cervical discectomy and fusion for degenerative disease over a 5-year period were entered into this study. Surgeries were performed with 1 of the dynamic plates for 1 to 3 levels. For the slotted-hole dynamic plate group, a slotted-hole plate was used (ABC, Aesculap, Tuttlingen, Germany or C-tek, Biomet, Parssipany, NJ) and for the fixed-hole dynamic plated group, a variable angled screw was used (C-tek, Biomet, Parssipany, NJ). Radiographic measurements included were graft subsidence, lordotic angle change from each end plate of fusion construct, and implant translation from end plates after a minimum of 12 months follow-up. Fusion state and clinical outcome using Odom's criteria were also evaluated. RESULTS: Demographics were not different among patient populations. The average age of the patients was 51.0 years (range: 27 to 77 y). Mean follow-up period was 20.6 months (range: 12 to 41 mo). Slotted-hole dynamic plates were used for 29 patients (ABC plate, 17; C-tek plate, 12) and fixed-hole dynamic plates for 27 patients. Clinical outcomes and pseudoarthrosis rates were similar for both types of plates. Radiographic measurements showed a statistically significant increased incidence of graft subsidence and implant translation with the slotted-hole dynamic plates. Loss of lordosis was also greater in the slotted-hole dynamic plated group, although the difference was not statistically significant. CONCLUSIONS: The use of a fixed-hole dynamic plate is more favorable in regards to graft subsidence and implant translation in the follow-up period, although clinical outcome and fusion rates are similar in patients with either the fixed-hole or slotted-hole dynamic plates.

Symptomatic ectopic bone formation after off-label use of recombinant human bone morphogenetic protein-2 in transforaminal lumbar interbody fusion.

OBJECT: Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been approved for use in the lumbar spine in conjunction with the lumbar tapered cage. However, off-label use of this osteoinductive agent is observed with anterior fusion applications as well as with both posterior lumbar interbody fusion and transforaminal lumbar interbody fusion (TLIF). Complications using rhBMP-2 in the cervical spine have been reported. Although radiographic evidence of ectopic bone in the lumbar spine has been described following rhBMP-2 use, this finding was not previously believed to be of clinical relevance. METHODS: This study was a retrospective review of 4 patients who underwent minimally invasive spinal TLIF (MIS-TLIF) in which bone fusion was augmented with rhBMP-2 applied to an absorbable collagen sponge. Case presentations, operative findings, imaging data, and follow-up findings were reviewed. RESULTS: Four cases with delayed symptomatic neural compression following the off-label use of rhBMP-2 with MIS-TLIF were identified. CONCLUSIONS: Although previously believed to be only a radiographic finding, the development of ectopic bone following rhBMP-2 use in lumbar fusion can be clinically significant. This paper describes 4 cases of delayed neural compression following MIS-TLIF. The reader should be aware of this potential complication following the off-label use of rhBMP-2 in the lumbar spine.

An intensive, progressive exercise program reduces disability and improves functional performance in patients after single-level lumbar microdiskectomy.

BACKGROUND: Restoration of physical function following lumbar microdiskectomy may be influenced by the postoperative care provided. OBJECTIVE: The purpose of this study was to examine the effectiveness of a new interventional protocol to improve functional performance in patients who have undergone a single-level lumbar microdiskectomy. SETTING: The study was conducted in physical therapy outpatient clinics. DESIGN AND PARTICIPANTS: Ninety-eight participants (53 male, 45 female) who had undergone a single-level lumbar microdiskectomy were randomly allocated to receive education only or exercise and education. INTERVENTION AND MEASUREMENTS: The exercise intervention consisted of a 12-week periodized program of back extensor strength (force-generating capacity) and endurance training and mat and upright therapeutic exercises. The Oswestry Disability Index (ODI) and physical measures of functional performance were tested 4 to 6 weeks postsurgery and 12 weeks later, following completion of the intervention program. Because some participants sought physical therapy outside of the study, postintervention scores were analyzed for both an as-randomized (2-group) design and an as-treated (3-group) design. RESULTS: In the 2-group analyses, exercise and education resulted in a greater reduction in ODI scores and a greater improvement in distance walked. In the 3-group analyses, post hoc comparisons showed a significantly greater reduction in ODI scores following exercise and education compared with the education-only and usual physical therapy groups. LIMITATIONS: The limitations of this study include a lack of adherence to group assignment, disproportionate therapist contact time among treatment groups, and multiple use of univariate analyses. CONCLUSIONS: An intensive, progressive exercise program combined with education reduces disability and improves function in patients who have undergone a single-level lumbar microdiskectomy.