Prevalence of venous thromboembolic events after elective major thoracolumbar degenerative spine surgery.

STUDY DESIGN: A case-control study. OBJECTIVE: The purposes of this study were to establish the prevalence of venous thromboembolic disease in patients undergoing elective major thoracolumbar degenerative spine surgery and identify risk factors. SUMMARY OF BACKGROUND DATA: Venous thromboembolic events (VTE) are a serious complication of orthopedic surgery, but the prevalence of VTE after elective thoracolumbar degenerative spine surgery is not well known. METHODS: This was a case-control study of 5766 consecutive elective thoracolumbar degenerative spine surgeries. Symptomatic pulmonary emboli (PE) were diagnosed by spiral chest CT scans, nuclear scintigraphic ventilation-perfusion, and angiography. Deep vein thromboses (DVT) were diagnosed by venous duplex scans. The prevalence of VTE was analyzed according to patient demographic variables and type of surgery performed. RESULTS: The prevalence of developing a VTE was 1.5% (89/5766), with a prevalence of symptomatic PE of 0.88% (51/5766) and DVT of 0.66% (38/5766). There were 47% males and 53% females with a mean age of 60.3 years. In patients undergoing 5-segment fusions the prevalence of PE was 3.1% (P=0.022). Patients who had ≥4 segments fused had a prevalence of PE of 1.7% (P=0.014). The odds of having a PE in those above 65 years at the time of surgery were 2.196 times as large as for those below 65 years. Noncontributory factors included sex, instrumentation, and revision surgery. CONCLUSIONS: This case-control study of 5766 patients who underwent elective thoracolumbar degenerative spine surgery revealed a prevalence of VTE of 1.5%, with a prevalence of PE of 0.88% and DVT of 0.66%. Patients with increasingly extensive surgery had a higher risk of PE, specifically those undergoing fusion of ≥5 segments.

Mortality in elderly patients following operative and nonoperative management of odontoid fractures.

STUDY DESIGN: Retrospective matched cohort study. OBJECTIVE: To compare mortality in elderly patients with odontoid fractures after operative and nonoperative treatment. In addition, to evaluate potential factors that may increase the risk of mortality in the geriatric population after odontoid fracture. SUMMARY OF BACKGROUND DATA: Odontoid fractures represent the most common cervical spine fracture in patients over 70. In this population controversy exists as to the optimal treatment of odontoid fractures, especially type II fractures. METHODS: A retrospective review of all odontoid fractures in patients 75 years of age or older at our institution from 1996 to 2010 was performed. Comorbidities were stratified using the Charlson comorbidity index. Mortality was determined at 3 months, 1, and 5 years. RESULTS: A total of 96 patients were identified of which 75 met inclusion criteria. The average age of patients included was 82.3 years. The average Charlson comorbidity score for those operated on (2.37) was not significantly different from the nonoperative group (2.46), (P=0.45). At 3 months the operative group had a significantly lower mortality rate than the nonoperative group (P=0.024). There was no significant difference in 1-year (P=0.42) or 5-year (P=0.21) mortality between the operative and nonoperative cohorts. Of the patients treated nonoperatively, those who died within 3 months of treatment had a significantly higher Charlson score (3.98) than those who survived (2.14). Patients who survived at least 1 year after surgery had a significantly lower Charlson score (1.53) than those who died (3.22) within that time frame after surgery (P=0.05). CONCLUSIONS: There was no significant difference between 1- and 5-year mortality in patients treated operatively or nonoperatively. Regardless of treatment Charlson score had a significant impact on mortality. Age significantly affected mortality in patients treated surgically.

Neuroforaminal chondrocyte metaplasia and clustering associated with recombinant bone morphogenetic protein-2 usage in transforaminal lumbar interbody fusion.

BACKGROUND CONTEXT: Recombinant human bone morphogenetic protein-2 (rhBMP-2) is commonly used to augment posterior and interbody spinal fusion techniques and has many reported side effects. Neuroforaminal heterotopic ossification (HO) is a known cause of postoperative leg pain, but the pathohistologic composition of this material is not well understood. PURPOSE: The purpose of this article was to report the histologic composition of a case of HO and lumbar radiculopathy after transforaminal lumbar interbody fusion with rhBMP-2. STUDY DESIGN/SETTING: This is a case report. PATIENT SAMPLE: This is a single patient case report. OUTCOME MEASURES: The outcomes considered were physician-recorded clinical, physiological, and functional measures. METHODS: A retrospective review of a single patient was performed. Clinical, radiographic, and pathologic specimens were reviewed and are reported. RESULTS: A 69-year-old woman presented with low back pain and right leg radicular pain associated with L4-L5 stenosis and a recurrent facet cyst. After attempted nonsurgical care, she underwent an L4-L5 revision decompression with interbody and posterolateral fusions including off-label rhBMP-2. Postoperatively, her symptoms resolved for approximately 7 months but then returned in association with right L4-L5 foraminal HO. The ectopic tissue was notably larger than suggested by preoperative computed tomographic scan. It was decompressed, which then improved her symptoms. Histologic examination of the specimen revealed three discrete tissue types: a nonspecific fibrovascular stroma; immature osteoid and woven bone; and chondrocyte metaplasia with chondrocyte clustering. CONCLUSIONS: Neuroforaminal HO formation is a reported side effect associated with the off-label use of rhBMP-2 for posterior lumbar interbody fusion. The mechanism of formation and the composition of this material are not well understood but may involve a chondrocyte differentiation pathway.

Congenital stenosis and adjacent segment disease in the cervical spine.

Symptomatic adjacent segment disease (ASD) after anterior cervical fusion (ACF) is reported in 25% of patients at 10 years postoperatively. Debate continues as to whether this degeneration is due to the natural history of the disk or the changed biomechanics after ACF. This study explored whether congenital stenosis predisposes patients to an increased incidence of ASD after ACF. A retrospective review of 635 patients with myelopathy or radiculopathy was performed; 364 patients had complete records for review. Patients underwent 1- to 5-level ACF (94 one-level, 145 two-level, 79 three-level, 45 four-level, and 1 five-level). Radiographs were evaluated for bony congenital stenosis using validated parameters, and ASD was measured according to Hilibrand's criteria and correlated with symptomatic ASD. Congenital stenosis was found in 21.7% of patients and radiographic ASD in 33.5%, with a significant association between these parameters. However, symptomatic ASD occurred in 11.8% of patients; no association between congenital stenosis and symptomatic ASD or myelopathy and ASD was found. Clinical results demonstrated excellent or good Robinson scores in 86.2% of patients and Odom scores in 87% of patients. Despite mostly excellent to good outcomes, symptomatic ASD is common after ACF. Although congenital stenosis appears to increase the incidence of radiographic ASD, it does not appear to predict symptomatic ASD.

Safety of thromboembolic chemoprophylaxis in spinal trauma patients requiring surgical stabilization.

STUDY DESIGN: Retrospective review. OBJECTIVE: To determine the incidence of thromboembolic events, bleeding complications such as epidural hematomas, and wound complications in patients with spinal trauma requiring surgical stabilization. SUMMARY OF BACKGROUND DATA: Literature addressing the safety and efficacy of chemoprophylactic agents in postoperative patients with spinal trauma is sparse. As a result, significant variability exists regarding administration of thromboembolic chemoprophylaxis in this population. The risk of bleeding complications is particularly concerning. METHODS: Patients with spinal trauma who underwent surgical stabilization in 2009 and 2010 at a single level 1 trauma center were retrospectively reviewed. Exclusion criteria included patients who underwent solely decompressive procedures, noninstrumented fusions, kyphoplasty, or had incomplete medical records. Patients who received chemoprophylaxis were compared with patients who did not. Demographical information and injury data were collected. Primary outcome measures were prevalence of thromboembolic events, epidural hematomas, and persistent wound drainage requiring irrigation and debridement. RESULTS: Two hundred twenty-seven of 373 patients were included (56 in the untreated group, 171 in the treated group). Eight patients in the untreated group (14.3%) and 12 patients in the treated group (7%) developed postoperative thromboembolism (P = 0.096). There was 1 pulmonary embolism in the untreated group (1.8%), and 4 pulmonary embolisms in the treated group (2.3%). Surgical irrigation and debridement for wound drainage was required for 1.8% of patients in the untreated group and for 5.3% of patients in the treated group. No epidural hematomas were noted in either group. The treated group had more spinal levels fused (P = 0.46), higher injury severity scores (0.001), and longer hospitalizations (0.018). Patients who developed postoperative thromboembolism had significantly higher body mass indexes (P = 0.01), injury severity scores (0.001), number of spinal levels fused (P = 0.004), incidence of neurological deficits (0.001), and longer hospitalizations (0.16) compared with those who did not. CONCLUSION: The use of chemoprophylaxis appears to be safe in at-risk patients in the immediate postoperative period after spinal trauma surgery. No epidural hematomas occurred, and the risk of wound drainage is small. Body mass index, injury severity score, presence of neurological deficits, and number of spinal levels fused should be considered when determining which patients should receive chemoprophylaxis after surgical stabilization.

Converting Scoliosis Research Society-24 to Scoliosis Research Society-22r in a Surgical-Range, Medical/Interventional Adolescent Idiopathic Scoliosis Patient Cohort.

STUDY DESIGN: Prospective questionnaire administration study. OBJECTIVES: To assess the ability to translate total and domain scores from Scoliosis Research Society (SRS)-24 to SRS-22r in a surgical-range, medical/interventional adolescent idiopathic scoliosis (AIS) patient population. SUMMARY OF BACKGROUND DATA: Conversion of SRS-24 to SRS-22r is demonstrated in an operative cohort of patients with AIS, but not in a medical/interventional patient population. METHODS: We simultaneously administered SRS-24 and SRS-22r questionnaires to 75 surgical-range, medical/interventional AIS patients and compared them. We performed analysis by regression modeling to produce conversion equations from SRS-24 to SRS-22r. RESULTS: The total SRS-24 score for these medical/interventional AIS patients was 92.5 ± 9.45 (mean, 3.9 ± 0.39), and the total SRS-22r score was 93.5 ± 9.63 (mean, 4.3 ± 0.44). The correlation between these 2 groups was fair (R2 = 0.77) and improved to good when mental health or recall questions were removed. The correlation was also fair for total pain domains (R2 = 0.73). However, there was poor correlation for general self-image (R2 = 0.6) and unacceptable for post-treatment self-image (R2 = 0.01), general function (R2 = 0.52), activity function (R2 = 0.56), and satisfaction (R2 = 0.53). Compared with a published population of operative AIS patients, R2 values for total SRS-24 scores, pain, general self-image, activity function, and satisfaction were similar (p > .05). The R2 values for general function and combined general and activity function were significantly different between the operative and medical/interventional cohorts. CONCLUSIONS: Scoliosis Research Society-24 can be converted to SRS-22r scores with fair accuracy in the surgical-range, medical/interventional AIS patient population for total score, and total pain domains. The SRS-24 translates unacceptably to the SRS-22r in self-image, function, and satisfaction domains. The SRS-24 to SRS-22r conversion equations are similar to operative AIS patients, except for the function domain. Caution should be used when interpreting results based on translation of SRS-24 to SRS-22r values.

Clinical indications for arterial imaging in cervical trauma.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: To evaluate the clinical indications for acquiring arterial imaging in cervical trauma. SUMMARY OF BACKGROUND DATA: Cervical spine injuries are very common in high-energy trauma and are frequently seen at Level I trauma centers across the country. A clinical standard of care does not exist to indicate when further evaluation of the cervical vasculature is warranted after a documented cervical spine injury. METHODS: After institutional review board approval, a retrospective study combining the data from 2 Level I trauma centers was undertaken. An evaluation of every arterial imaging procedure (computed tomography and magnetic resonance angiography) of the cervical spine was collected to further delineate indications and outcomes of these imaging modalities. RESULTS: From 2005 to 2009, there were a total of 159 patients who underwent cervical arterial imaging at the 2 participating institutions for the indication of cervical trauma with concern for arterial injury. Thirty-six (22.64%) were found to have an injury after arterial imaging. There was a statistically significant correlation with displaced cervical injuries (P < 0.0153), which were defined as cervical dissociations or perched and/or jumped facets. The other statistically significant correlation was the presence of a neurological deficit (P < 0.001), defined as any presenting deficit on sensory or motor examination. Level of injury defined as axial (O-C2) versus subaxial (C3-C7), age, body mass index, and history of cigarette smoking were not statistically related to vascular injury. CONCLUSION: Our retrospective evaluation indicates that there should be a lower threshold for obtaining arterial imaging with cervical injury patterns historically known to compromise the vasculature, which also have concomitant displaced cervical spine injuries and/or a neurological deficit.

Dysphagia after anterior cervical spine surgery: a prospective study using the swallowing-quality of life questionnaire and analysis of patient comorbidities.

STUDY DESIGN: Prospective study of 29 patients who underwent anterior cervical (AC) or posterior lumbar (PL) spinal surgery. A validated measure of dysphagia, the Swallowing-Quality of Life (SWAL-QOL) survey, was used to assess the degree of postoperative dysphagia. OBJECTIVE: To determine the degree of dysphagia preoperatively and postoperatively in patients undergoing AC surgery compared with a control group that underwent PL surgery. SUMMARY OF BACKGROUND DATA: Dysphagia is a well-known complication of AC spine surgery and has been shown to persist for up to 24 months or longer. METHODS: A total of 18 AC patients and a control group of 11 PL patients were prospectively enrolled in this study and were assessed preoperatively and at 3 weeks and 1.5 years postoperatively using a 14-item questionnaire from the SWAL-QOL survey to determine degree of dysphagia. Other patient factors and anesthesia records were examined to evaluate their relationship to dysphagia. RESULTS: There were no significant differences between the AC and PL groups with respect to age, sex, body mass index, or length of surgery. The SWAL-QOL scores at 3 weeks were significantly lower for the AC group than for the PL group (76 vs. 96; P = 0.001), but there were no differences between the groups preoperatively or at final follow-up. Smokers, patients with chronic obstructive pulmonary disease, and women had lower SWAL-QOL scores at one or more time point. CONCLUSION: Patients undergoing AC surgery had a significant increase in the degree of dysphagia 3 weeks after surgery compared with patients undergoing PL surgery. By final follow-up, swallowing in the AC group recovered to a level similar to preoperative and comparable to that in patients undergoing lumbar surgery at 1.5 years. Smoking, chronic obstructive pulmonary disease, and female sex are possible factors in the development of postoperative dysphagia.

Aberrant right subclavian artery encountered during debridement of T2 osteomyelitis and associated phlegmon.

BACKGROUND CONTEXT: An aberrant right subclavian artery is a rare congenital abnormality of the aortic arch. The anomalous origin for the right subclavian artery arises as the last branch of the thoracic aorta. In the most common anomalous form, the right subclavian artery passes posterior to both the esophagus and trachea as it crosses midline to supply the right upper extremity. The aberrant right subclavian artery is often not symptomatic, but it can cause dysphagia. PURPOSE: To describe a case of an aberrant right subclavian artery discovered during debridement of T2 osteomyelitis. STUDY DESIGN: Case report. METHODS: A 49-year-old woman with diabetes was transferred to our institution with bilateral lower extremity weakness and incontinence of bowel and bladder function. Examination revealed no motor function in quadriceps, hamstrings, tibialis anterior, extensor hallucis longus, or gastrocsoleus complex of her bilateral lower extremities. RESULTS: Spinal computed tomography scan showed pathologic collapse of the T2 vertebra. Magnetic resonance (MR) demonstrated an abscess and a phlegmon anterior to T2. Magnetic resonance also demonstrated spinal cord compression at the T2 vertebral level, and T2-weighted MR demonstrated the presence of spinal cord signal changes. CONCLUSIONS: We report a rare case where an aberrant right subclavian artery was associated with a T2 osteomyelitis and paravertebral abscess. The intraoperative injury to this aberrant artery led to the eventual death of the patient. When planning an anterior approach to the upper thoracic region, surgeons should be aware of this anatomic variant of the subclavian artery and its associated aberrant recurrent laryngeal nerve.

Surgeons agree to disagree on surgical options for degenerative conditions of the cervical and lumbar spine.

STUDY DESIGN: This is a survey study designed to evaluate agreement among spine surgeons regarding treatment options for six clinical scenarios involving degenerative conditions of the cervical and lumbar spine. OBJECTIVES: The purpose was to evaluate whether or not surgeons agree on which cases require operative intervention and what type of surgery should be performed. SUMMARY OF BACKGROUND DATA: Agreement between spine surgeons on when to operate and what procedure to perform is a subject that has received increasing attention. This is an important question in the field of spine surgery, where "gold standards" that are based on large clinical trials are relatively sparse. METHODS: Six clinical vignettes were presented to 19 members of the Degenerative Spine Study Group. Each vignette was accompanied by a series of radiographs and/or magnetic resonance imagings, followed by treatment options in multiple-choice format. Two months later, the same vignettes were sent out with identical instructions except that they were now told they were treating a close family member. RESULTS: More than 76% of surgeons agreed on whether or not to recommend surgical intervention for the following four cases: lumbar degenerative spondylolisthesis with stenosis, cervical herniated nucleus pulposus, lumbar spondylosis, and lumbar herniated nucleus pulposus. Two scenarios had approximately 50% surgeon agreement: cervical stenosis and lumbar spondylolysis. However, despite good inter-rater agreement about who needed surgery, there was poor agreement regarding what procedure to perform if surgery was recommended. When repeating the survey in the setting of operating on a family member, only 17 (17.7%) of 96 recommendations were changed. CONCLUSION: Spine surgeons in this survey generally agreed on when to operate but failed to agree on what type of procedures to perform.

Laminoplasty versus laminectomy and fusion for multilevel cervical spondylotic myelopathy.

BACKGROUND: Cervical spondylotic myelopathy is increasingly prevalent in the elderly and is the leading cause of spinal cord dysfunction in this population. Laminectomy with fusion and laminoplasty halt progression of myelopathy in these patients; however, both procedures have well-documented complications and associated morbidity and it is unclear which might be most advantageous. QUESTIONS/PURPOSES: We therefore compared the pain, function and alignment of patients who underwent laminectomy with fusion to those with laminoplasty for the treatment of multilevel cervical spondylotic myelopathy. METHODS: We performed a retrospective matched cohort analysis on all 121 patients from 2002 to 2007 who underwent laminectomy with fusion (82) or laminoplasty (39) for multilevel cervical spondylotic myelopathy. We determined change in preoperative and postoperative sagittal alignment using Cobb measurement, development of junctional stenosis, and subjective improvements in pain and gait. Complications were recorded for both cohorts. RESULTS: The majority of patients in both cohorts reported improvements in pain and gait postoperatively. There were seven complications in the laminectomy and fusion cohort (9%) with two patients requiring formal revision surgery (2%). There were five complications in the laminoplasty cohort (13%) with two formal revision procedures (5%). CONCLUSIONS: Patients in both the laminectomy with fusion and laminoplasty cohorts reported similar functional improvements after treatment for cervical spondylotic myelopathy. Prospective randomized control trials are needed to determine whether one procedure is truly superior. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

A novel classification system for traumatic central cord syndrome: the central cord injury scale (CCIS).

STUDY DESIGN: Retrospective study of 37 patients with traumatic central cord syndrome. OBJECTIVE: The purpose of this study is to review a series of patients with central cord syndrome and to introduce a classification system that is predictive of functional outcome. SUMMARY OF BACKGROUND DATA: Central cord syndrome is the most common incomplete spinal cord injury, yet a predictive classification system does not exist. METHODS: Thirty-seven patients with traumatic central cord syndrome had 1-year results of the motor portion of the Functional Independence Measurement (FIM) Score. Ten factors were analyzed for their predictive effect on the 1-year Motor FIM Score. RESULTS: There were 8 women and 29 men with a mean age of 55.1 years. The mean injury motor FIM was 21.9 and mean 1-year Motor FIM: 70.2 (P < 0.001). The following had a predictive effect on 1-year Motor FIM: Injury ASIA Motor Score (P < 0.013) and magnetic resonance imaging evidence of abnormal signal intensity (P < 0.007). Points were assigned to these factors, and patients were categorized as Central Cord Injury Scale (CCIS) 1, 2, or 3. CCIS 1: n = 6, mean 1-year Motor FIM = 40.8; CCIS 2: n = 19 and FIM = 72.4; and CCIS 3: n = 12 and FIM = 81.5. Each classification had an increasing percentage of patients who could walk without ever using a wheelchair and had independence in bladder and bowel function. CONCLUSION: The CCIS is predictive of a patient's functional outcome at 1 year and has the potential to help patients and physicians establish realistic expectations for functional recovery based on ASIA Motor Score and magnetic resonance imaging findings.

Dysphonia, dysphagia, and esophageal injuries after anterior cervical spine surgery.

Anterior cervical spine surgery is commonly used by spine surgeons to treat numerous pathologic entities. The most common procedures involve decompression of the cervical spine through either diskectomy or corpectomy. Procedures that involve anterior dissection of the neck can lead to various complications, including dysphonia, dysphagia, and esophageal injuries.