✓ The authors describe a case of paraspinal calcinosis in a 65-year-old woman with progressive systemic sclerosis. Although calcinosis occurs in up to 27% of cases of progressive systemic sclerosis, symptomatic paraspinal calcinosis is extremely rare. In the case reported here, multiple cervical facet joints were compromised by progressive calcinosis, leading to glacial spinal instability. Internal fixation was indicated to correct the instability and decompress the spinal canal. Medical therapy was instituted to arrest or reverse the ongoing calcinosis.
Marc S. Arginteanu and Noel I. Perin
Raj K. Shrivastava, Marc S. Arginteanu, Wesley A. King and Kalmon D. Post
Object. Giant prolactinomas are rare tumors whose treatment and outcome has only been addressed in isolated case reports. The authors document the long-term follow-up findings and clinical outcome in a group of patients with giant prolactinomas.
Methods. This study is a retrospective chart and clinical review of more than 2000 cases of pituitary tumors treated at the authors' institution, of which 10 met the criteria for inclusion (prolactin level > 1000 ng/ml, diameter > 4 cm on neuroimaging studies, and clinical signs of hyperprolactinemia/mass effect). The average follow-up duration was 6.7 years after initial treatment with either bromocriptine or transsphenoidal resection. In more than 90% of the patients in this series the disease was controlled by medical treatment with bromocriptine alone; the other 10% required early surgery via transsphenoidal resection. All patients had improvement in visual symptoms. All tumors had extrasellar components, five of which exhibited frank invasion of the cavernous sinus. Tumor volume on magnetic resonance imaging was decreased on average by 69%; this occurred at a faster rate and in larger amounts when treated with bromocriptine than has been reported in the literature for macroprolactinomas.
Conclusions. According to long-term follow-up findings, giant prolactinomas are exquisitely responsive to dopamine agonist therapy. In giant prolactinomas the prolactin level does not correlate with size. The main indication for early surgery is intratumoral hematoma, whereas our main indications for late surgery are cerebrospinal fluid leakage caused by medical treatment, or an increasing prolactin level despite medical therapy. Checking prolactin levels in suspicious sellar and/or suprasellar lesions may be diagnostic and prevent unnecessary surgery.
Paul S. Saphier, Marc S. Arginteanu, Frank M. Moore, Alfred A. Steinberger and Martin B. Camins
In a prospective analysis the authors evaluated the clinical and radiographic outcome of 50 consecutive patients who underwent anterior cervical discectomy and fusion and fixation in which either a stress-shielding or a load-sharing plate (Orion and Premier, respectively) was placed. Data obtained in the two cohorts were analyzed to determine whether clinical or radiographic differences would emerge.
All patients underwent either one- or two-level fusion in which freeze-dried allogenic tricortical iliac crest bone graft was used. In the first cohort of 25 patients entered into the study, fixation was achieved using a stress-shielding anterior cervical plate (ACP) system, whereas in the second cohort of 25 patients a load-sharing plate system was employed. Patients were evaluated during a follow-up period that ranged from 12 to 35 months. Outcome was determined using a standard questionnaire by which the authors gauged the level of pain, disability, and satisfaction following surgery. The success of surgical fusion and the magnitude of the translation were determined by radiographic evaluation.
There was no statistically significant difference between the two cohorts with respect to age, sex, smoking rate, and postoperative complications. With regard to pain and functionality, there was a significant difference (p < 0.05) in favor of the load-sharing system. The fusion rates with the load-sharing and stress-shielding systems were 96 and 92%, respectively, and this difference was not significant. There was no significant difference between the two cohorts with regard to overall satisfaction. The magnitude of vertical translation was significantly greater in the stress-shielding ACP group (p < 0.05) for treatment at one level but not at two. Clinical and radiographic data were available in all patients.
Load-sharing ACP systems exhibited superior clinical results compared with stress-shielding ACPs in this series of patients. The symptomatic pseudarthrosis rate was lower in the load-sharing ACP–treated patients, although this was not statistically significant.
Case report and review of the literature
Caleb R. Lippman, Marc Arginteanu, Dushayant Purohit, Thomas P. Naidich and Martin B. Camins
✓ This case of a 68-year-old woman with a low-thoracic intramedullary neurenteric cyst is notable for clinical presentation, cyst location, intraoperative findings, and imaging characteristics. The patient's postoperative course was complicated by neurological deterioration and a neuropathic pain syndrome. Potential causes of these complications are discussed, as are possible ways to reduce the risk of their occurrence.
Arien J. Smith, Marc Arginteanu, Frank Moore, Alfred Steinberger and Martin Camins
Recent advances in the field of spinal implants have led to the development of the bioabsorbable interbody cage. Although much has been written about their advantageous characteristics, little has been reported regarding complications associated with these cages. The authors conducted this prospective cohort study to compare fusion and complication rates in patients undergoing transforaminal lumbar interbody fusion (TLIF) with carbon fiber cages versus biodegradable cages made from 70/30 poly(l-lactide-co-d,l-lactide) (PLDLA).
Between January 2005 and May 2006, 81 patients with various degenerative and/or structural pathologies affecting the lumbar spine underwent single- or multilevel TLIF with posterior segmental pedicle screw fixation using implants made of carbon fiber (37 patients) or 70/30 PLDLA (44 patients). Clinical and radiological follow-up was performed at 6 weeks, 3 months, 6 months, and 1 year, and is ongoing. The incidence of nonunion, screw breakage, and cage migration were compared between the 2 groups.
There was no significant difference in demographic data between the 2 groups, the mean number of lumbar levels operated, or distribution of the levels operated. There was a significantly increased incidence of nonunion (8 patients, 18.2%) and cage migrations (8 patients, 18.2%) in patients receiving the PLDLA implants compared with carbon fiber implants (no patients) (p = 0.006 and 0.007, respectively). There was no significant difference in demographic data between patients with cage migration and the rest of the patient population. Five of the 8 cases of migration occurred at the L5–S1 level while the remaining 3 occurred at the L4–5 level. The mean time to implant failure was 9.3 months.
This study showed an increased incidence of nonunion (18.2%) and postsurgical cage migration (18.2%) in patients undergoing TLIF with biodegradable cages versus carbon fiber implants (0%) (p = 0.006 and 0.007, respectively).
Yakov Gologorsky, Branko Skovrlj, Jeremy Steinberger, Max Moore, Marc Arginteanu, Frank Moore and Alfred Steinberger
Transforaminal lumbar interbody fusion (TLIF) with segmental pedicular instrumentation is a wellestablished procedure used to treat lumbar spondylosis with or without spondylolisthesis. Available biomechanical and clinical studies that compared unilateral and bilateral constructs have produced conflicting data regarding patient outcomes and hardware complications.
A prospective cohort study was undertaken by a group of neurosurgeons. They prospectively enrolled 80 patients into either bilateral or unilateral pedicle screw instrumentation groups (40 patients/group). Demographic data collected for each group included sex, age, body mass index, tobacco use, and Workers' Compensation/litigation status. Operative data included segments operated on, number of levels involved, estimated blood loss, length of hospital stay, and perioperative complications. Long-term outcomes (hardware malfunction, wound dehiscence, and pseudarthrosis) were recorded. For all patients, preoperative baseline and 6-month postoperative scores for Medical Outcomes 36-Item Short Form Health Survey (SF-36) outcomes were recorded.
Patient follow-up times ranged from 37 to 63 months (mean 52 months). No patients were lost to follow-up. The patients who underwent unilateral pedicle screw instrumentation (unilateral cohort) were slightly younger than those who underwent bilateral pedicle screw instrumentation (bilateral cohort) (mean age 42 vs 47 years, respectively; p = 0.02). No other significant differences were detected between cohorts with regard to demographic data, mean number of lumbar levels operated on, or distribution of the levels operated on. Estimated blood loss was higher for patients in the bilateral cohort, but length of stay was similar for patients in both cohorts. The incidence of pseudarthrosis was significantly higher among patients in the unilateral cohort (7 patients [17.5%]) than among those in the bilateral cohort (1 patient [2.5%]) (p = 0.02). Wound dehiscence occurred for 1 patient in the unilateral cohort. Reoperation was offered to 8 patients in the unilateral cohort and 1 patient in the bilateral cohort (p = 0.03). The physical component scores of the Medical Outcomes SF-36 outcomes improved significantly for all patients (p < 0.001).
Transforaminal lumbar interbody fusion with either unilateral or bilateral segmental pedicular instrumentation is an effective treatment for lumbar spondylosis. Because patients with unilateral constructs were 7 times more likely to experience pseudarthrosis and require reoperation, TLIF with bilateral constructs might be the biomechanically superior technique.
Marc S. Arginteanu, Karin Hague, Robert Zimmerman, Mark J. Kupersmith, John H. Shaiu, John Schaeffer and Kalmon D. Post
✓ The authors report the case of a 55-year-old woman who developed a symptomatic craniopharyngioma within 2 years of obtaining a normal magnetic resonance image of her brain. Craniopharyngiomas are histologically benign tumors. They are thought to arise from embryonic remnants of Rathke's pouch and sac and to manifest themselves clinically after a steady growth that commences in fetal life. To the authors' knowlege, this is the first report that documents a tumor arising de novo in the sixth decade of life. This report appears to challenge the concept of the origin and natural history of craniopharyngiomas.
Harel Deutsch, Marc Arginteanu, Karen Manhart, Noel Perin, Martin Camins, Frank Moore, A. Abe Steinberger and Donald J Weisz
Object. Spine surgeons have used intraoperative cortical and subcortical somatosensory evoked potential (SSEP) monitoring to detect changes in spinal cord function when intraoperative procedures can be performed to prevent neurological deterioration. However, the reliability of SSEP monitoring as applied to anterior thoracic vertebral body resections has not been rigorously assessed.
Methods. The authors retrospectively reviewed hospital charts and operating room records obtained between August 1993 and December 1998 and found that SSEP monitoring was used in 44 surgical procedures involving an anterior approach for thoracic vertebral body resections.
There were no patients in whom SSEP changes did not return to baseline during the surgical procedure. Patients in four cases, despite their stable SSEP recordings throughout the procedure, were noted immediately postoperatively to have experienced significant neurological deterioration. The false-negative rate in SSEP monitoring was 9%. Sensitivity was determined to be 0%.
Conclusions. It is important to recognize high false-negative rates and low sensitivity of SSEP monitoring when it is used to record spinal cord function during anterior approaches for thoracic vertebrectomies. The insensitivity of SSEPs for motor deterioration during anterior thoracic vertebrectomies is likely due to the limitation of SSEPs, which monitor only posterior column function whereas motor paths are conveyed in the anterior and anterolateral spinal cord. The authors believe that SSEPs can not be relied on to detect reversible spinal damage during anterior thoracic vertebrectomies.