Use of O-arm with neuronavigation in percutaneous vertebroplasty reduces the surgeon's exposure to intraoperative radiation.

INTRODUCTION: Percutaneous vertebroplasty is commonly used to treat spinal fractures. The authors compare radiation exposure as potential risk for the surgical team during vertebroplasty guided by O-arm combined with neuronavigation versus vertebroplasty guided by C-arm fluoroscopy. MATERIAL AND METHODS: The clinical material consisted of a group of 29 patients (44 vertebrae) with fractures of the thoracolumbar spine treated with percutaneous vertebroplasty guided by O-arm with neuronavigation. In this new method, the operating room staff leaves the operating room for the duration of the 3D scan of the appropriate spine section using the O-arm. In the next stage, the needle of the vertebroplasty system is introduced using only neuronavigation without the need for a radiological view. Finally, the cement injection was made under O-arm fluoroscopic control. The comparison group consisted of a group of 35 patients (40 vertebrae) treated with the classical method using C-arm fluoroscopy. The two methods were compared in terms of the average dose of emitted ionizing radiation through the device (O-arm vs. C-arm) to which surgeons are exposed during percutaneous vertebroplasty. RESULTS: As a result of vertebroplasty procedures guided by neuronavigation, a statistically significant difference between the values of mean dose of radiation emitted by O-arm and C-arm systems was noted. The O-arm emitted 912 cGy/cm2 vs. 1722 cGy/cm2 emitted by the C-arm during fluoroscopically assisted procedures and 601.28 cGy/cm2 vs. 1506.86 cGy/cm2 per vertebrae. CONCLUSIONS: During vertebroplasty with the O-arm combined with neuronavigation the radiation dose is significantly lower as compared with the C-arm used for fluoroscopic guidance, minimizing the potential risk of radiation exposure to surgeons.

Vagus Nerve Stimulation For Treatment Resistant Depression: Case Series Of Six Patients - Retrospective Efficacy And Safety Observation After One Year Follow Up.

OBJECTIVE: One year observation and evaluation of the VNS (vagus nerve stimulation) efficacy and safety for patients with treatment resistant depression in Polish conditions. METHODS: An open label, uncontrolled and one center retrospective study of VNS therapy was implemented with stable pharmacotherapy in 6 patients with treatment resistant depression (TRD). For the first 3 months, only VNS parameters were altered but the pharmacological treatment was unchanged and in the following 9 months, medication and VNS dosing parameters were altered according to the clinical state of the patients. RESULTS: The baseline 24-item Hamilton Depression Rating Scale (HAMD-24) score averaged 24. Both response (>50% reduction in baseline scores) and remission rates after 3 months of treatment were only 40%. After 1 year of VNS therapy, the response rates increased to 86%. Most frequent side-effects were voice alteration (86% at 3 months of stimulation) and headaches (40%). CONCLUSION: VNS treatment was safe and effective in TRD patients and its efficacy increased with time. Efficacy ratings are similar to the previously reported studies using a congenial protocol.

The distribution of brachial plexus lesions after experimental traction: a cadaveric study.

OBJECTIVEThe objective of the present study was to determine experimentally the distribution of lesions caused in the cadaveric brachial plexus (BP) by excessive stretching. The authors attempted to delineate the correlation between the direction of stretching and sites of lesions.METHODSFifteen specimens (each comprised the spinal segment C4-T2 with 2 BPs) were harvested from adult cadavers. Each BP was stretched in a mechanical testing machine at a constant speed of 200 mm/min. Specimens were divided into 3 groups: in group A the BPs were stretched caudally at a 45° angle to the spinal midline; in group B they were stretched perpendicularly to the spinal midline; and in group C the stretching was caudally parallel to the midline. Lesions of each BP were identified and analyzed. A graph of load against dislocation was registered when stretching to delineate the maximal force (Fmax), defined as the maximum load at which BP failure occurs.RESULTSBased on macroscopic examination, 140 sites of mechanical damage were identified in 30 BPs. Preganglionic injuries (63.6% of lesions), defined as avulsions of the spinal ganglia with their rootlets, were found in 89 spinal nerves. In group B-in which specimens were stretched perpendicularly to the spinal segment-preganglionic injuries were significantly more frequent (41 avulsed spinal nerves) than in groups A and C (21 and 27 avulsed spinal nerves, respectively). Postganglionic lesions equivalent to neurotmesis were found in 51 sites (36.4% of all lesions) along spinal nerves, trunks, divisions, and cords. Postganglionic lesions in group B were much less frequent (8) as compared with groups A and C (24 and 19, respectively).CONCLUSIONSPredominance of preganglionic lesions suggests that attachments of the BP to the spine are more susceptible to traction than postganglionic elements. Preganglionic lesions were mainly produced in C7, C8, and T1 spinal nerves, suggesting their weaker attachment to the spine than in the case of C5 and C6 nerves. Preganglionic lesions were highly correlated with a traction perpendicular to the spine, whereas postganglionic lesions were provoked mainly by traction directed at 45° caudally or by means of caudal traction parallel to the midline. This discrepancy implies a relationship between mechanical resistance of pre- and postganglionic elements of the BP and the vector of force.

In vitro simulation of intraoperative vertebroplasty applied for pedicle screw augmentation. A biomechanical evaluation.

BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the effect of an in vitro simulation of intraoperative vertebroplasty on embedded pedicle screws resistance to pullout. This method involved an application of acrylic cement into the vertebral bodies only after pedicle screws implementation. MATERIALS AND METHODS: For the purpose of conducting this research, the authors used the spines of fully-grown pigs. The procedure was as follows: firstly, the pedicle screws were bilaterally implemented in 10 vertebrae; secondly, cancellous bone was removed from vertebral bodies selected for screws augmentation and lastly it was replaced by polymethylmethacrylate (PMMA). Six vertebrae with implemented pedicle screws served as a control group. The pullout strength of thirty-two screws (20 augmented and 12 control) was tested. All screws were pulled out at a crosshead speed of 5mm/min. RESULTS: The PMMA-augmented screws showed a 1.3 times higher average pullout force than the control group: respectively 1539.68N and 1156.59N. In essence, no significant discrepancy was determined between average pullout forces of screws which were pulled as first when compared with consecutive contralateral ones. CONCLUSIONS: An in vitro simulation of intraoperative injection of PMMA in the vertebral body instrumented with screws (intraoperative vertebroplasty) resulted in enhancing its pullout strength by 33%. Pulling of one of the pedicular screws from the augmented vertebral body did not affect the pullout resistance of the contralateral one.

Tumoral calcinosis of the cervical spine in a dialysis patient. Case report and review of the literature.

The authors present a case of tumoral calcinosis (TC) in a patient with chronic renal insufficiency. The clinical course, imaging features and microscopic findings are detailed. A 60-year-old woman with a 4-year history of hemodialysis presented with a painful mass in the right posterior cervical triangle. The neuroimaging revealed polycystic mass bulging from the C3-C5 facet joints and lamina on the right. The majority of cystic mass was excised and microscopic features of the specimen were consistent with TC. Tumoral calcinosis is a rare disease characterized by calcium salt deposits in periarticular soft tissue, which enlarge to form tumor-like cystic masses containing chalky calcareous material. TC is typically seen around large joints but rarely in the spine. Review of past publications provided six cases of TC involving the spine in dialyzed patients.

Vertebral hemangioma coincident with metastasis of colon adenocarcinoma.

The authors report on colon cancer metastasis to the L-3 vertebra, which had been previously found to be involved by an asymptomatic hemangioma. A 61-year-old female patient was admitted after onset of lumbar axial pain and weakness of the right quadriceps muscle. Her medical history included colon cancer that had been diagnosed 3 years earlier and was treated via a right hemicolectomy followed by chemotherapy. Presurgical imaging revealed an asymptomatic hemangioma in the L-3 vertebral body. Computed tomography and MRI of the spine were performed after admission and revealed a hemangioma in the L-3 vertebral body as well as a soft-tissue mass protruding from the L-3 vertebral body to the spinal canal. Treatment consisted of vertebroplasty of the hemangioma, left L-3 hemilaminectomy, and removal of the pathological mass from the spinal canal and the L-3 vertebral body. Histopathological examination revealed the presence of colon cancer metastasis and a hemangioma in the same vertebra.

Percutaneous balloon kyphoplasty in the treatment of painful vertebral compression fractures: effect on local kyphosis and one-year outcomes in pain and disability.

BACKGROUND AND PURPOSE: The aim of the study was to determine the effectiveness of percutaneous balloon kyphoplasty for treatment of compressive vertebral fractures. MATERIALS AND METHODS: A retrospective analysis was conducted on 24 patients with 58 symptomatic vertebral fractures treated by balloon kyphoplasty. Visual Analogue Pain Scale (VAS) and Oswestry Disability Index (ODI) were used to assess fracture-related pain and patient's disability: preoperatively and within 12-months follow-up. Following the procedures to evaluate the change of vertebral deformity, the angle of local kyphosis was measured. RESULTS: Preoperative VAS score was 6.54, at discharge it significantly regressed in 95.8% of patients. The overall VAS score at discharge was 1.25 and within 12 months decreased to 0.26. Preoperative ODI score was 50%, at follows-up in all patients it decreased, ranging from 21% to 10%. Reduction of local kyphosis was achieved in 30 (51.7%) vertebrae by average 4.3°. In 9 (37.5%) patients kyphosis of all augmented vertebrae was reduced, in 7 (29.2%) patients procedures reduced kyphosis in part of augmented vertebrae and in 8 patients (33.3%) kyphosis remained unchanged. Asymptomatic complications included cement leak in 10 (17%) vertebrae and intraoperative rupture of 4 (4%) balloons. CONCLUSIONS: Rapid significant pain relief after kyphoplasty followed by long-term pain release and disability reduction obtained in all patients was most probably the result of vertebral augmentation. The correction of local kyphosis had no influence on the outcome.

Delayed perforation of posterior pharyngeal wall caused by dislodged bioresorbable interbody cage. Case report.

A 48-year-old man was admitted for the management of congenital anomalies: Arnold-Chiari type I malformation combined with odontoid upward migration. He also had degenerative stenosis of the spinal canal by spurs at C2/C3 and C3/C4 levels. Osseous deformities caused ischaemic changes of the brainstem as well as spinal cord compression. Authors used the Biocage - interbody cage covered by bioresorbable layer to fill the surgically created gap after removal of the right part of C3 vertebral body. Twenty-seven months after implantation, the implant was extruded through posterior pharyngeal wall. Authors describe this unusual case and discuss possible causes of Biocage extrusion.

The use of calcium phosphate cement in vertebroplasty of the base of odontoid process.

The authors describe the use of bone cement containing calcium phosphate for vertebroplasty of the cavity in the base of odontoid process. A 23-year-old female patient was operated on by incision in lateral cervical area (anterior open access). After a blunt dissection, the working cannula (Kyphon) was introduced under fluoroscopic guidance through the C2 vertebral body to the cavity in the base of the odontoid process. Intraoperatively, biopsy of the lesion was taken and histo-pathological examination excluded the presence of neoplasm. The cavity, presumably haemangioma, was successfully filled with calcium phosphate bone cement KyphOsTM FS (Ky-phon). The proper filling without paravertebral cement leak was confirmed by postoperative computed tomography (CT). The CT and magnetic resonance imaging performed 9 months after the procedure showed that cement was still present in the cavity. This is the first use of calcium phosphate cement to conduct the vertebroplasty of C2 vertebra.

Augmentation of transpedicular screws by intraoperative vertebroplasty.

BACKGROUND AND PURPOSE: The aim of the study was to determine the efficacy of posterior spinal stabilization, combined with intraoperative vertebroplasty defined as intraoperative filling of instrumented vertebral bodies (VB) with polymethylmethacrylate (PMMA). MATERIAL AND METHODS: Seventeen patients with osteoporosis or osteopenia underwent posterior spinal fusions. The surgical procedures included laminectomy, spondylodesis, insertion of pedicular screws, intraoperative vertebroplasty and correction of spinal deformity. RESULTS: Postoperative assessment showed improvement of pain in all cases. Motor deficit regressed in 2 of 3 afflicted patients. In 12 vertebrae (27.3%), the mass of PMMA ex-tended from one endplate to another, filling 100% of VB height, in 7 (15.9%) it filled 90-99%, in 14 (31.8%) 80-89%, in 9 (20.4%) 70-79%, and in 2 (4.5%) it filled 50-60% of VB height. In the horizontal plane, PMMA filled central parts of 72.7% of vertebral bodies. PMMA completely surrounded 68.9% of screws, and partially surrounded 18.4% of screws, whereas 12.6% of screws had no contact with cement mass. Spinal stabilization reduced kyphotic deformity in 15 patients (range of reduction: 6°-25°; mean: 13.6°). During follow-up (3-32 months; mean: 16) implants of 11 patients were stable, 1 implant instability was diagnosed 7 months after surgery, 5 patients were lost to follow-up. Asymptomatic cement leaks occurred in 45% of vertebrae. CONCLUSIONS: Intraoperative vertebroplasty performed after insertion of pedicular screws may be considered as a technical variation useful to stabilize osteoporotic spines. After PMMA hardening, intraoperative manoeuvres to correct spinal deformity were possible without any damage of instrumented vertebrae.

Balloon kyphoplasty for painful C-7 vertebral hemangioma.

The authors report on the efficacy of balloon kyphoplasty applied to obliteration of symptomatic cervical hemangioma. This 49-year-old woman suffered from progressive neck pain, numbness of the upper extremities, and frequent headaches. Hemangioma of the C-7 vertebral body was diagnosed. Kyphoplasty was performed successfully through a right anterolateral approach. The patient became asymptomatic, and follow-up examinations confirmed complete recovery. To the authors' knowledge, this is the first description of cervical hemangioma treated by balloon kyphoplasty.

[Minimally invasive percutaneous transpedicular lumbar spine fixation. Operative technique and a case report]. / Maloinwazyjna przezskórna stabilizacja przeznasadowa odcinka ledzwiowego kregoslupa. Prezentacja techniki i opis przypadku.

Transpedicular fixation systems are commonly used in lumbar spine surgery for the treatment of a variety of pathologies making the solid fusion of operated spinal segments possible. Recently there has been a big interest in minimally invasive techniques in spinal surgery, including minimally invasive fixation systems. By minimizing the operative trauma minimally invasive techniques allow patients to restore activity faster. In the paper the authors present the Sextant system (Medtronic Sofamor Danek), which provides minimally invasive (percutaneous) fixation. Before fixing the spine, it is necessary to perform discectomy and interbody fusion using the PLIF or ALIF method. The authors present the system, describe the operative technique, and present a case of the patient with L4/L5 spondylolisthesis successfully treated using this technique.

Percutaneous vertebroplasty in the treatment of diseases causing vertebral bone loss.

Background. Percutaneous vertebroplasty involves the injection of acrylic surgical cement into the vertebral body. The basic principles of vertebroplasty and the authors' own clinical experiences are described. Material and methods. Between November 1999 and January 2005 the authors performed percutaneous vertebroplasty on 75 patients: 45 with osteoporotic compression fractures, 15 with angiomas of the vertebral bodies, and 12 patients with spinal neoplasms. There were also 3 patients with coexisting spinal angiomas and osteoporotic compression fractures. All these patients were treated under local anesthesia. Cement injections were realized by the transpedicular approach under fluoroscopic guidance; in certain cases a CT-guided approach was used. The clinical outcome was assessed based on follow-up examinations, the Oswestry questionnaire, and the Visual Analog Pain Scale. Plain x-rays or CT scans were made for purposes of radiological evaluation. Results. Follow-up examinations revealed pain relief or significant reduction of pain in 89% of the patients. In 2 cases (3%) vertebroplasty was complicated by intracanal leakage of cement. Conclusions. Percutaneous vertebroplasty is well tolerated by patients. Filling with cement is effective in the treatment of osteoporotic compression fractures and of vertebral angiomas.

Experimental investigations of traction injury of the brachial plexus. Model and results.

AIM: The study was realized in purpose to investigate mechanical properties of the human brachial plexus. Authors present model of experiments and biomechanical results obtained after controlled stretching of specimens. Investigations were supported by Polish Ministry of Education (Grant KBN 3 P05C 072 22), under permission of Committee of Bioethics. MATERIAL AND METHODS: Thirty specimens isolated from cadavers were distracted with a speed 20 cm/min. Mechanical tests were realised by means of apparatus INSTRON 4000. During stretching following data were registered: maximal force provoking mechanical failure of specimen and elongation in the point of mechanical failure. Stiffness of the brachial plexus was also calculated. Anatomic investigations were realised in purpose to define the most frequent type of lesion. RESULTS: The mean value of force leading to rupture of human brachial plexus was 630 N. The mean value of elongation in the point of rupture was 37%.

[Direct fixation of the odontoid fracture in a child]. / Bezposrednie zespolenie zlamania zeba kregu obrotowego u dziecka.

The use of spinal implants in the pediatric population is controversial in terms of skeletal immaturity. The authors present the case of a 12-year-old boy with displaced Type III odontoid fracture, successfully treated by direct screw fixation. Fractures defined as Type II and Type III according to the classification by Anderson and D'Alonzo are instable spinal injuries. Type III fractures generally heal when treated conservatively. In certain circumstances, like displaced fractures or patients refusing long-term external immobilization, Type III fractures are treated surgically. A 12-year-old boy had neck injury caused by a bike accident. His main symptoms were neck pain and limitation of neck movements. Displaced Type III odontoid fracture was diagnosed. The authors treated this lesion surgically by screw fixation in order to correct displacement and to preserve the normal range of head motion. Fixation was performed by means of a single cannulated screw. Healing of the fracture was confirmed by roentgenograms done at follow-up examinations. The range of motion of the cervical spine examined 6 months after operation was normal. Direct anterior screw fixation was an effective method for treating displaced Type III odontoid fracture in a child. The rotatory motion between C-1 and C-2 was preserved.

Percutaneous vertebroplasty with bone cement in the treatment of osteoporotic vertebral compression fractures.

Background. The authors report their own experience with percutaneous vertebroplasty. This is minimally invasive method indicated in treatment of certain spinal lesions affecting the vertebral bodies, as osteoporotic fractures, angiomas, neoplasms. The basic principle of this method is insertion of the needle into the vertebral body by transpediculat access. Needle gives an access for biopsy and therapeutic cement injection. Material and methods. Since October 1999 the authors treated 11 patients with osteoporotic compressive fractures of the spinal column. All patients suffered from severe back pain. Transpedicular insertion of the needle was realized under radiofluoroscopy or CT guidance. Fractured vertebral bodies were injected by Methylmethacrylate bone cement Palacos R. Results. All patients declared important improvement, no complications were observed. Conclusions. Transpedicular vertebroplasty is is effective in treatment of vertebral osteoporotic compression fractures. Minimally invasive procedure requiring local anaesthesia is well-tolerated by patients. Cement injection protects the vertebral body against further compression.

Percutaneous vertebroplasty with methyl methacrylate bone cement in the treatment of spinal angiomas and neoplasms.

Background. The authors report their own experience with percutaneous vertebroplasty. Percutaneous vertebroplasty is a technique which allows to inject acrylic surgical cement into the vertebral body. This is minimally invasive method indicated in treatment of certain spinal lesions affecting the vertebral bodies, as osteoporotic fractures, angiomas and focal neoplasms.
Material and methods. Since October 1999 the authors treated 7 patients with angiomas of the vertebral bodies and 11 patients with spinal neoplasms. Cement injections were realized under local anesthesia.
Results. In group of 7 cases with spinal metastases 3 patients declared important pain relief. All 7 patients with spinal angiomas declared no pain in follow-up.
Conclusions. Percutaneous vertebroplasty is well-tolerated by patients. Filling by cement is efficace in treatment of vertebral angiomas. Filling of spinal neoplasmatic lesions result in palliative pain relief.

Strategy in the diagnostics and therapy of tumours of the spine.

The authors present the diagnostic methods and basic surgical procedures used in treatment of spinal neoplasms. Both metastatic and primary spinal tumours lead to instability and loss of the protective function. Spinal cord can be damaged by compression or increased mobility of the vertebral column. Pain is reported as common symptom. Investigations include: plain X-ray films, myelography, radioisotope bone scan, CT, MRI and needle biopsy. The goal of surgery is to improve the quality of life with preservation of neurological function, reduction of pain and assured spinal stability. Indications for surgery are related with patient's general condition, grade of neoplasmatic disease, neurological symptoms and spinal involvement. Curative surgery include total removal of the tumour with affected vertebral body, followed by spinal stabilization. Palliative surgery as partial tumour removal, partial removal of the vertebral body or laminectomy are performed for spinal decompression. In the majority of cases surgery is combined with radiotheraphy, chemiotheraphy and treatment of pain.
Main goal of surgery in the treatment of spinal metastatic lesions are: tumor removal (cytoreduction), protection of the spinal cord and spinal stabilization. The choice of surgical treatment depends on spinal involvement and neurological status.

[Atlanto-occipital instability due to the transverse atlas ligament rupture. Report of a case with symptoms persisting for 21 years]. / Niestabilnosc szczytowo-obrotowa jako skutek przerwania wiezadla poprzecznego kregu szczytowego. Prezentacja przypadku o wieloletnim przebiegu.

The authors describe a case of a judo sportsman with a cervical spine injury sustained 21 years earlier. The injury initiated characteristic sensations of severe generalized pain with paraesthesias recurring whenever he was hit on the top of the head. In February 2001 the patient fell on his head, which resulted in tetraplegia with a complete sensory loss. The symptoms disappeared after ten minutes. Plain radiography, CT and MRI performed after this episode revealed occipitalization of the atlas and C1-C2 instability due to a rupture of the transverse atlas ligament. The patient underwent surgery by the posterior approach: decompression of the foramen magnum, fixation of the occiput and C-2 (with wiring and a bone graft). At one-year follow-up after the surgery the patient had limited movements of the neck without neurological symptoms. Plain radiograms confirmed stability of the occipitocervical fusion. There was no recurrence of the preoperative symptoms.