BACKGROUND

CONTEXT:

Aeromonas hydrophila is a motile gram-negative non-sporeforming rod with facultative anaerobic metabolism. Except for gastrointestinal disease, skin and soft-tissue infections represent the second most common site of human Aeromonas infections. However, to our knowledge, A. hydrophila infection of the spine has not been reported to date.

PURPOSE:

To report the first case of A. hydrophila spinal infection of the T7 vertebra after vertebroplasty.

STUDY DESIGN:

Case report.

METHODS:

A 72-year-old man was transferred to our emergency department with chief complaints of severe midthoracic pain and triparesis. He had undergone vertebroplasty for a painful vertebral fracture at T7 5 weeks before transfer. Magnetic resonance imaging showed an infection of the T7 vertebroplasty and an extensive epidural abscess. The epidural abscess originating from the infected T7 vertebroplasty extended from the T8 to the C4 epidural space. Computed tomography demonstrated sparsely scattered gas in the epidural abscess, strongly suggestive of an anaerobic infection.

RESULTS:

Emergency multilevel laminectomies from C5 to T8 and a posterior instrumentation from T3 to T10 were performed. A. hydrophila was isolated from the blood cultures. The patient was treated with intravenous ampicillin/sulbactam. Posterior decompression and stabilization in combination with appropriate antibiotic treatment completely resolved the neurologic deficit and infection without the need for further anterior corpectomy of the infected T7 vertebroplasty.

CONCLUSIONS:

This is the first reported case of spine infection caused by A. hydrophila. The infection developed after vertebroplasty for the management of a painful vertebral fracture. Triparesis occurred rapidly due to an extensive epidural abscess containing gas. Emergency decompression and stabilization in combination with appropriate antibiotic treatment achieved a successful clinical outcome.

BACKGROUND

CONTEXT:

Intervertebral disc degeneration, leading to chronic back pain, is a major health problem in western societies. Vertebral bone marrow has been considered to play an important role in nutrition supply and metabolic exchange for discs. Vertebral bone marrow lesions, including fatty marrow replacement and inflammatory edema, noted on magnetic resonance imaging were first described in 1988.

PURPOSE:

To investigate the potential of a free radical scavenger, fullerol nanoparticles, to prevent vertebral bone marrow lesion and prevent disc degeneration by inhibiting inflammation and adipogenic differentiation of vertebral bone marrow stromal cells (vBMSCs).

STUDY DESIGN

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SETTING:

Fullerol nanoparticle solutions were prepared to test their in vitro suppression effects on mouse vBMSC inflammation and adipogenic differentiation compared with non-fullerol-treated groups.

METHODS:

With or without fullerol treatment, vBMSCs from Swiss Webster mice were incubated with 10 ng/mL interleukin-1 β (IL-1 β). The intracellular reactive oxygen species (ROS) were measured with fluorescence staining and flow cytometry. In addition, vBMSCs were cultured with adipogenic medium (AM) with or without fullerol. Gene and protein expressions were evaluated by real-time polymerase chain reaction and histologic methods.

RESULTS:

Fluorescence staining and flow cytometry results showed that IL-1 β markedly increased intracellular ROS level, which could be prevented by fullerol administration. Fullerol also decreased the basal ROS level to 77%. Cellular production of matrix metalloproteinase (MMP)-1, 3, and 13 and tumor necrosis factor alpha (TNF-α) induced by IL-1 β was suppressed by fullerol treatment. Furthermore, adipogenic differentiation of the vBMSCs was retarded markedly by fullerol as revealed by less lipid droplets in the fullerol treatment group compared with the adipogenic group. The expression of adipogenic genes PPARγ and aP2 was highly elevated with AM but decreased on fullerol administration.

CONCLUSIONS:

These results suggest that fullerol prevents the catabolic activity of vBMSCs under inflammatory stimulus by decreasing the level of ROS, MMPs, and TNF-α. Also, fat formation in vBMSCs is prevented by fullerol nanoparticles, and, therefore, fullerol may warrant further in vivo investigation as an effective biological therapy for disc degeneration.

BACKGROUND

CONTEXT:

Primary solitary amyloidosis or amyloidoma is a disease process characterized by the focal deposition of amyloid in the absence of a plasma cell dyscrasia with normal serum protein measurements. Solitary amyloidomas affecting the vertebrae are very uncommon but typically affect the thoracic spine. Primary cervical amyloidosis is an exceedingly rare entity with exceptionally good prognosis, but requires diligence of the treating physician to establish the diagnosis and implement the appropriate surgical intervention.

PURPOSE:

This study aimed to present a rare case of primary cervical amyloidosis with long-term follow-up and review the clinical presentation, characteristic imaging findings, diagnostic pathology, differential diagnosis, treatment algorithm, and prognosis of the disease entity. This case demonstrates the progressive resorption of the amyloidoma over time after surgical stabilization. Previous reported cases of primary cervical amyloidosis will also be reviewed.

STUDY DESIGN:

This study is a report and review of the literature.

METHODS:

A 77-year-old woman presented with a several-week history of gradual progressive weakness in her upper and lower extremities. Computed tomography and magnetic resonance imaging demonstrated a retro-odontoid nonenhancing soft-tissue mass, with erosive bony changes and severe mass effect on the upper cervical cord. The patient was taken to the operating room for decompression and posterior spinal stabilization.

RESULTS:

Intraoperative tissue specimens demonstrated amyloidosis and extensive systemic workup did not reveal any inflammatory processes, systemic amyloidosis, or plasma cell dyscrasia. Postoperatively, the patient regained full strength and ambulatory status. The patient remains asymptomatic at a 2-year follow-up. A postoperative follow-up magnetic resonance imaging demonstrated complete resorption of the residual amyloidoma.

CONCLUSIONS:

Primary solitary amyloidosis is a rare form of amyloidosis that is important to differentiate given its excellent prognosis with surgical management. Treatment should include surgical decompression and spinal stabilization. This is the first case report to clinically and radiographically demonstrate the progressive resorption of a primary amyloidoma over time after surgical stabilization in the upper cervical spine. It is imperative that surgeons encountering such lesions maintain a high suspicion for this rare disease entity and advise their pathologists accordingly to establish the correct diagnosis.

BACKGROUND

CONTEXT:

Iatrogenic dural tears are common complications encountered in spine surgery with known ramifications. There is little information, however, with respect to the implications and complications of traumatic dural tears.

PURPOSE:

To describe the demographics and characteristics of traumatically acquired dural tears and evaluate the complication rate associated with traumatic dural tears in patients who have undergone surgical treatment for spine injuries.

STUDY DESIGN:

Retrospective review of a single Level I trauma center to identify patients with traumatic dural tears between January 1, 2003 and December 31, 2009. PATIENT SAMPLE: The sample comprises 187 patients with traumatic dural tears identified from 1,615 patients who underwent operative management of their traumatic injury.

OUTCOME MEASURES:

The outcome measures consisted of a description of the location and nature of dural tears and associated fracture patterns and neurologic status as well as an assessment of complications attributable to the traumatic dural tear.

METHODS:

No funding was received or used in this study. In total, 1,615 operatively managed spine injuries over a 7-year period were reviewed to identify 187 patients with traumatic dural tears. Operative reports were reviewed to assess location and description of injury as well as type of repair, if done. Associated spinal cord injuries as well as fracture level, patterns, and complications were recorded. Postoperative records were assessed focusing on complications related to the traumatic dural tears.

RESULTS:

Traumatic dural tears were identified in 9.1% (67/739) of cervical, 9.9% (45/452) of thoracic, and 17.6% (75/424) of lumbosacral spine fractures. Among the patients, 82.3% (154/187) had a formal dural repair. Fracture patterns included burst (AO Type A3) 26.2% (49/187), flexion distraction (AO Type B) 16% (30/187), and fracture dislocations (AO Type C) 36.4% (68/187). A complete neurologic injury was noted in 48.7% (91/187) of the patient population, whereas no neurologic injury was noted in 17.1% (32/187). Two patients (1%) developed a persistent cerebral spinal fluid leak that necessitated an irrigation and debridement with exploration and closure of the cerebral spinal fluid tear. Two patients (1%) developed a pseudomeningocele; one required a return to the operating room for irrigation and debridement, and the other suspected of having developed meningitis was treated with intravenous antibiotics. Among the patients, 2.1% (4/187) were noted to have a complication directly related to a traumatic dural tear.

CONCLUSIONS:

Traumatic dural tears occurred in 11.6% of patients with operatively managed traumatic spine injuries at a regional Level 1 trauma center. In total, 83% had a neurologic injury and 49% had complete spinal cord injuries. Patients with traumatically induced dural tears have a low likelihood of developing a complication attributable to the dural tear.

COMMENTARY ON: Lansford TJ, Burton DC, Asher MA, Lai S-M. Radiographic and patient-based outcome analysis of different bone grafting techniques in the surgical treatment of idiopathic scoliosis with minimum four-year follow-up: allograft vs. autograft/allograft combination. Spine J 2013;13:523-9 (in this issue).

COMMENTARY ON: Gire JD, Roberto RF, Bobinski M, et al. The utility and accuracy of computed tomography in the diagnosis of occipitocervical dissociation. Spine J 2013;13:510-9 (in this issue).

COMMENTARY ON: Adogwa O, Parker SL, Shau DN, et al. Preoperative Zung depression scale predicts patient satisfaction independent of extent of improvement after revision lumbar surgery. Spine J 2013;13:501-6 (in this issue).

COMMENTARY ON: Kepler CK, Yu AL, Gruskay JA, et al. Comparison of open and minimally invasive techniques for posterior lumbar instrumentation and fusion after open anterior lumbar interbody fusion. Spine J 2013;13:489-97 (in this issue).

COMMENTARY ON: Zhou C, Liu L, Song Y, et al. Two-stage vertebral column resection for severe and rigid scoliosis in patients with low body weight. Spine J 2013;13:481-6 (in this issue).

BACKGROUND

CONTEXT:

In pedicle screw fixation, accurate insertion is essential to avoid neurological injury or weak stability. The percutaneous pedicle screw system was developed for minimally invasive spine surgery, and its safety has already been reported. However, the accuracy of percutaneous pedicle screw fixation (PPF) has not been compared with that of the open system to date.

PURPOSE:

To compare the accuracy of PPF with that of open pedicle screw fixation (open PF) and to investigate the risk factors associated with pedicle wall penetration.

STUDY DESIGN

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SETTING:

A retrospective case series. PATIENT SAMPLE: The study group included 237 patients who underwent posterior pedicle screw fixation between January 2008 and October 2010 at a single institute with a total of 1,056 pedicle screw fixations completed. One hundred and twenty-six patients with 558 screws underwent open PF and 111 patients with 498 screws underwent PPF.

OUTCOME MEASURES:

Postoperative computerized tomography, including sagittal and coronal reformatted images.

METHODS:

Consecutive surgeries with either conventional open PF or PPF for anterior lumbar interbody fusion or transforaminal lumbar interbody fusion were performed. The open pedicle screw employed was from the WSH system (Winova, Seoul, Korea), and the two percutaneous pedicle screw systems were the Sextant (Medtronics, Minneapolis, MN, USA) and the Viper systems (DePuy Spine, Raynham, MA, USA). Computed tomography images were evaluated to determine pedicle wall penetration after operation. Severity was classified as mild (<3 mm), moderate (3-6 mm), and severe (≥6 mm), and the direction was assessed as medial, lateral, inferior, and superior.

RESULTS:

Pedicle wall penetration occurred in 75 patients (13.4%) in the open PF group and 71 patients (14.3%) in the PPF group and was not statistically different between the groups (p=.695). Assessment of the severity of the pedicle wall penetration revealed that minor penetration was the most common (open PF group, 9.7%; PPF group, 10.6%), although the distribution of the degree of severity was not statistically different between the groups (p=.863). A relatively higher incidence of lateral penetration was observed in the open PF group (66.7% vs. 43.7%), whereas medial, superior, and inferior penetrations were higher in the PPF group (p=.033). Other parameters such as age, sex, surgical method, and surgeon factors did not influence the penetration rate, but bone mineral densitometry negatively correlated with the penetration.

CONCLUSIONS:

Pedicle wall penetration during screw fixation was not different between the open PF and PPF groups. The lateral, paraspinal, muscle-splitting approach seems to lessen medial wall penetration, especially in the S1 vertebra. Distribution of the direction of penetration differs between the groups, with lateral wall penetration being more prominent in the open PF group. Careful placement of pedicle screws is necessary for a stronger construct because of the high incidence of penetration.