Hormuzdiyar H. Dasenbrock

The efficacy of minimally invasive discectomy compared with open discectomy: a meta-analysis of prospective randomized controlled trials

OBJECT Advocates of minimally invasive discectomy (MID) have promoted this operation as an alternative to open discectomy (OD), arguing that there may be less injury to the paraspinal muscles, decreased postoperative pain, and a faster recovery time. However, a recently published large randomized controlled trial (RCT) comparing these approaches reported inferior relief of leg pain in patients undergoing MID. The authors conducted a meta-analysis to evaluate complications and improvement in leg pain in patients with radiculopathy enrolled in RCTs comparing OD to MID. METHODS The authors performed a literature search using Medline and EMBASE of studies indexed between January 1990 and January 2011. Predetermined RCT eligibility included the usage of tubular retractors during MID, a minimum follow-up duration of 1 year, and quantification of pain with the visual analog scale (VAS). Trials that only evaluated patients with recurrent disc herniation were excluded. Data on operative parameters, complications, and VAS scores of leg pain were extracted by 2 investigators. A meta-analysis was performed assuming random effects to determine the difference in mean change for continuous outcomes and the risk ratio for binary outcomes. RESULTS Six trials comprising 837 patients (of whom 388 were randomized to MID and 449 were randomized to OD) were included. The mean operative time was 49 minutes during MID and 44 minutes during OD; this difference was not statistically significant. Incidental durotomies occurred significantly more frequently during MID (5.67% compared with 2.90% for OD; RR 2.05, 95% CI 1.05-3.98). Intraoperative complications (incidental durotomies and nerve root injuries) were also significantly more common in patients undergoing MID (RR 2.01, 95% CI 1.07-3.77). The mean preoperative VAS score for leg pain was 6.9 in patients randomized to MID and 7.2 in those randomized to OD. With long-term follow-up (1-2 years postoperatively), the mean VAS score improved to 1.6 in both the MID and OD cohorts. There was no significant difference in relief of leg pain between the 2 approaches with either short-term follow-up (2-3 months postoperatively, 0.81 points on the VAS, 95% CI -4.71 to 6.32) or long-term follow-up (2.64 on the VAS, 95% CI -2.15 to 7.43). Reoperation for recurrent herniation was more common in patients randomized to the MID group (8.50% compared with 5.35% in patients randomized to the OD group), but this difference was not statistically significant (RR 1.56, 95% CI 0.92-2.66). Total complications did not differ significantly between the operations (RR 1.50, 95% CI 0.97-2.33). CONCLUSIONS The current evidence suggests that both OD and MID lead to a substantial and equivalent long-term improvement in leg pain. Adequate decompression, regardless of the operative approach used, may be the primary determinant of pain relief-the major complaint of many patients with radiculopathy. Incidental durotomies occurred significantly more frequently during MID, but total complications did not differ between the techniques.

The impact of provider volume on the outcomes after surgery for lumbar spinal stenosis.

BACKGROUND Investigation into the provider volume-outcomes association for patients undergoing spine surgery has been limited. OBJECTIVE To examine the impact of surgeon and hospital volume on the outcomes after decompression with or without fusion for lumbar spinal stenosis. METHODS Data from the Nationwide Inpatient Sample (2005-2008) were retrospectively extracted. Multivariate logistic regression analyses were performed to calculate the adjusted odds of in-hospital mortality and the development of a postoperative complication with increasing surgeon or hospital volume. Provider volume was evaluated continuously and categorically, divided by percentiles into quintiles. Very-low-volume surgeons performed < 15 procedures over 4 years. All analyses were adjusted for differences in patient age, sex, comorbidities, and primary payer, as well as hospital bed size, teaching status, and location (urban vs rural). RESULTS A total of 48,971 admissions were examined. In-hospital mortality did not differ significantly with increasing provider volume. When examined continuously, greater surgeon volume was associated with a significantly lower adjusted odds of developing a complication (odds ratio, 0.72; 95% confidence interval, 0.65-0.78; P < .001). Patients who underwent surgery by very-low-volume surgeons (odds ratio, 1.38; 95% confidence interval, 1.19-1.60; P = .001), but not those treated by low-, medium-, or high-volume surgeons, had a significantly higher complication rate compared with those who underwent surgery by very high-volume surgeons. After adjustment for surgeon volume, hospital volume was not significantly associated with in-hospital mortality or complications. CONCLUSION In this nationwide study, patients treated by very-low-volume surgeons had a significantly higher complication rate compared with those treated by very high-volume surgeons.

Endoscopic image-guided transcervical odontoidectomy: Outcomes of 15 patients with basilar invagination

BACKGROUND: Ventral decompression with posterior stabilization is the preferred treatment for symptomatic irreducible basilar invagination. Endoscopic image-guided transcervical odontoidectomy (ETO) may allow for decompression with limited morbidity. OBJECTIVE: To describe the perioperative outcomes of patients undergoing anterior decompression of basilar invagination with the use of ETO. METHODS: Fifteen patients who had a follow-up of at least 16 months were retrospectively reviewed. Intraoperatively, the vertebral body of C2 was removed and the odontoid was resected in a “top-down” manner using endoscopic visualization and frameless stereotactic navigation. Posterior instrumented stabilization was subsequently performed. RESULTS: The average (± standard deviation) age of the patients was 42.6 ± 24.5 (range, 11-72) years. Postoperative complications occurred in 6 patients, including a urinary tract infection (n = 2), upper airway swelling (n = 2), dysphagia (n = 2), gastrostomy tube placement (n = 1), and an asymptomatic pseudomeningocele (n = 1). No patients required a tracheostomy, had bacterial meningitis, or developed a venous thromboembolic event; only 1 patient was intubated for more than 48 hours postoperatively. With a mean follow-up of 41.9 ± 14.4 (range, 16-59) months, myelopathy improved in all patients and no patient experienced late neurological deterioration. The mean modified Japanese Orthopedic Association (JOA) score increased from 11.2 ± 4.2 to 15.9 ± 1.4 (P = .002). Patients with a diagnosis other than rheumatoid arthritis or who had a higher preoperative JOA score had a significantly better postoperative neurological recovery (P = .005). CONCLUSION: ETO may be a valid treatment for patients with symptomatic irreducible basilar invagination that avoids some of the morbidity of transoral surgery and leads to long-term improvement in myelopathy.

Posterior-only approach for en bloc sacrectomy: Clinical outcomes in 36 consecutive patients

BACKGROUND En bloc resection of primary sacral tumors has a demonstrated survival benefit. Total and high sacral amputations are traditionally performed by using a staged anterior and subsequent posterior approach. However, we have found that en bloc resection and biomechanical reconstruction of the spinal column is possible from a posterior-only approach in many cases. OBJECTIVE To assess our series of posterior-only sacrectomies, emphasizing postoperative complications and overall surgical and oncologic outcome. METHODS Sixty-nine consecutive patients underwent sacral resections for tumor at our institution between 2004 and 2009. Medical records of all patients were reviewed, and patients were excluded if they had an intentional intralesional resection, hemipelvectomy, or a previous operation. The records of the resulting 36 consecutive patients who underwent primary posterior-only en bloc sacral resections were retrospectively reviewed. RESULTS Of the posterior-only patients, all underwent midline posterior approaches for en bloc sacral resection. Sacral amputation was defined by the by sacral root preservation: total (2 cases), high (8 cases), middle (9 cases), low (12 cases), and distal (5 cases). Chordoma was the most common tumor type (30 cases), and surgical margins were marginal in 34 cases and contaminated in 2. Overall, there were 13 complications, including 9 wound infections/revisions. The extent of sacrectomy, and thus the extent of roots sacrificed, correlated with functional outcome. CONCLUSION It may be possible to perform a posterior-only approach to en bloc sacral resections/reconstructions in patients with tumors that do not extend beyond the lumbosacral junction or invade the bowel requiring bowel resection and diversion.

Diffusion Tensor Imaging of the Optic Tracts in Multiple Sclerosis: Association with Retinal Thinning and Visual Disability

Visual disability is common in multiple sclerosis, but its relationship to abnormalities of the optic tracts remains unknown. Because they are only rarely affected by lesions, the optic tracts may represent a good model for assessing the imaging properties of normal‐appearing white matter in multiple sclerosis.

Length of hospital stay after craniotomy for tumor: a National Surgical Quality Improvement Program analysis.

OBJECT Although the length of hospital stay is often used as a measure of quality of care, data evaluating the predictors of extended hospital stay after craniotomy for tumor are limited. The goals of this study were to use multivariate regression to examine which preoperative characteristics and postoperative complications predict a prolonged hospital stay and to assess the impact of length of stay on unplanned hospital readmission. METHODS Data were extracted from the National Surgical Quality Improvement Program (NSQIP) database from 2007 to 2013. Patients who underwent craniotomy for resection of a brain tumor were included. Stratification was based on length of hospital stay, which was dichotomized by the upper quartile of the interquartile range (IQR) for the entire population. Covariates included patient age, sex, race, tumor histology, comorbidities, American Society of Anesthesiologists (ASA) class, functional status, preoperative laboratory values, preoperative neurological deficits, operative time, and postoperative complications. Multivariate logistic regression with forward prediction was used to evaluate independent predictors of extended hospitalization. Thereafter, hierarchical multivariate logistic regression assessed the impact of length of stay on unplanned readmission. RESULTS The study included 11,510 patients. The median hospital stay was 4 days (IQR 3-8 days), and 27.7% (n = 3185) had a hospital stay of at least 8 days. Independent predictors of extended hospital stay included age greater than 70 years (OR 1.53, 95% CI 1.28%-1.83%, p < 0.001); African American (OR 1.75, 95% CI 1.44%-2.14%, p < 0.001) and Hispanic (OR 1.68, 95% CI 1.36%-2.08%) race or ethnicity; ASA class 3 (OR 1.52, 95% CI 1.34%-1.73%) or 4-5 (OR 2.18, 95% CI 1.82%-2.62%) designation; partially (OR 1.94, 95% CI 1.61%-2.35%) or totally dependent (OR 3.30, 95% CI 1.95%-5.55%) functional status; insulin-dependent diabetes mellitus (OR 1.46, 95% CI 1.16%-1.84%); hematological comorbidities (OR 1.68, 95% CI 1.25%-2.24%); and preoperative hypoalbuminemia (OR 1.78, 95% CI 1.51%-2.09%, all p ≤ 0.009). Several postoperative complications were additional independent predictors of prolonged hospitalization including pulmonary emboli (OR 13.75, 95% CI 4.73%-39.99%), pneumonia (OR 5.40, 95% CI 2.89%-10.07%), and urinary tract infections (OR 11.87, 95% CI 7.09%-19.87%, all p < 0.001). The C-statistic of the model based on preoperative characteristics was 0.79, which increased to 0.83 after the addition of postoperative complications. A length of stay after craniotomy for tumor score was created based on preoperative factors significant in regression models, with a moderate correlation with length of stay (p = 0.43, p < 0.001). Extended hospital stay was not associated with differential odds of an unplanned hospital readmission (OR 0.97, 95% CI 0.89%-1.06%, p = 0.55). CONCLUSIONS In this NSQIP analysis that evaluated patients who underwent craniotomy for tumor, much of the variance in hospital stay was attributable to baseline patient characteristics, suggesting length of stay may be an imperfect proxy for quality. Additionally, longer hospitalizations were not found to be associated with differential rates of unplanned readmission.

The impact of July hospital admission on outcome after surgery for spinal metastases at academic medical centers in the United States, 2005 to 2008

Despite widespread belief that patients admitted to teaching hospitals in July—the beginning of the academic year—have inferior outcomes, there has been little evidence to support the existence of the July phenomenon. Moreover, the impact of July admission on the outcomes after surgery for spinal metastases has not been investigated.

Reconstruction of extensive defects from posterior en bloc resection of sacral tumors with human acellular dermal matrix and gluteus maximus myocutaneous flaps

BACKGROUND Performing a sacrectomy from an exclusively posterior approach allows the en bloc resection of tumors without the morbidity of a laparotomy. However, reconstruction of the resultant extensive soft-tissue defects is challenging because a vertical rectus abdominis myocutaneous flap is not harvested. OBJECTIVE To report the largest series (with the longest follow-up) of sacral reconstructions using a combination of human acellular dermal matrix (HADM) and gluteus maximus myocutaneous flaps. METHODS Thirty-four patients with sacral tumors with a follow-up of at least 1 year were reviewed retrospectively. After the tumor was excised, HADM (AlloDerm, LifeCell Corp, Branchburg, New Jersey) was secured to create a pelvic diaphragm. Subsequently, the gluteus maximus muscles were freed from their origins and advanced to cover the HADM. RESULTS The mean age of patients was 50.1 years (SD, 16.0 years), and the histopathology was a chordoma in 82.4%. Seven patients (20.6%) developed a postoperative wound dehiscence, 5 of whom (14.7%) required operative debridement. An estimated blood loss of >1500 mL, an operative time of >9 hours during sacrectomy, and postoperative bowel incontinence were associated with a significantly higher likelihood of undergoing a subsequent debridement for dehiscence (P ⩽ .03). With a mean follow-up of 45.7 months, only 1 patient developed an asymptomatic parasacral hernia. CONCLUSION Reconstruction of posterior sacrectomy defects with HADM and gluteus maximus myocutaneous flaps may be valid. This approach may have rates of wound dehiscence comparable to other techniques and low rates of parasacral herniation.

Thirty-day readmission and reoperation after surgery for spinal tumors: a National Surgical Quality Improvement Program analysis

OBJECTIVE The goal of this study was to use a large national registry to evaluate the 30-day cumulative incidence and predictors of adverse events, readmissions, and reoperations after surgery for primary and secondary spinal tumors. METHODS Data from adult patients who underwent surgery for spinal tumors (2011-2014) were extracted from the prospective National Surgical Quality Improvement Program (NSQIP) registry. Multivariable logistic regression was used to evaluate predictors of reoperation, readmission, and major complications (death, neurological, cardiopulmonary, venous thromboembolism [VTE], surgical site infection [SSI], and sepsis). Variables screened included patient age, sex, tumor location, American Society of Anesthesiologists (ASA) physical classification, preoperative functional status, comorbidities, preoperative laboratory values, case urgency, and operative time. Additional variables that were evaluated when analyzing readmission included complications during the surgical hospitalization, hospital length of stay (LOS), and discharge disposition. RESULTS Among the 2207 patients evaluated, 51.4% had extradural tumors, 36.4% had intradural extramedullary tumors, and 12.3% had intramedullary tumors. By spinal level, 20.7% were cervical lesions, 47.4% were thoracic lesions, 29.1% were lumbar lesions, and 2.8% were sacral lesions. Readmission occurred in 10.2% of patients at a median of 18 days (interquartile range [IQR] 12-23 days); the most common reasons for readmission were SSIs (23.7%), systemic infections (17.8%), VTE (12.7%), and CNS complications (11.9%). Predictors of readmission were comorbidities (dyspnea, hypertension, and anemia), disseminated cancer, preoperative steroid use, and an extended hospitalization. Reoperation occurred in 5.3% of patients at a median of 13 days (IQR 8-20 days) postoperatively and was associated with preoperative steroid use and ASA Class 4-5 designation. Major complications occurred in 14.4% of patients: the most common complications and their median time to occurrence were VTE (4.5%) at 9 days (IQR 4-19 days) postoperatively, SSIs (3.6%) at 18 days (IQR 14-25 days), and sepsis (2.9%) at 13 days (IQR 7-21 days). Predictors of major complications included dependent functional status, emergency case status, male sex, comorbidities (dyspnea, bleeding disorders, preoperative systemic inflammatory response syndrome, preoperative leukocytosis), and ASA Class 3-5 designation (p < 0.05). The median hospital LOS was 5 days (IQR 3-9 days), the 30-day mortality rate was 3.3%, and the median time to death was 20 days (IQR 12.5-26 days). CONCLUSIONS In this NSQIP analysis, 10.2% of patients undergoing surgery for spinal tumors were readmitted within 30 days, 5.3% underwent a reoperation, and 14.4% experienced a major complication. The most common complications were SSIs, systemic infections, and VTE, which often occurred late (after discharge from the surgical hospitalization). Patients were primarily readmitted for new complications that developed following discharge rather than exacerbation of complications from the surgical hospital stay. The strongest predictors of adverse events were comorbidities, preoperative steroid use, and higher ASA classification. These models can be used by surgeons to risk-stratify patients preoperatively and identify those who may benefit from increased surveillance following hospital discharge.

The impact of aspirin and anticoagulant usage on outcomes after aneurysmal subarachnoid hemorrhage: a Nationwide Inpatient Sample analysis.

OBJECTIVE Although aspirin usage may be associated with a decreased risk of rupture of cerebral aneurysms, any potential therapeutic benefit from aspirin must be weighed against the theoretical risk of greater hemorrhage volume if subarachnoid hemorrhage (SAH) occurs. However, few studies have evaluated the association between prehemorrhage aspirin use and outcomes. This is the first nationwide analysis to evaluate the impact of long-term aspirin and anticoagulant use on outcomes after SAH. METHODS Data from the Nationwide Inpatient Sample (NIS; 2006-2011) were extracted. Patients with a primary diagnosis of SAH who underwent microsurgical or endovascular aneurysm repair were included; those with a diagnosis of an arteriovenous malformation were excluded. Multivariable logistic regression was performed to calculate the adjusted odds of in-hospital mortality, a nonroutine discharge (any discharge other than to home), or a poor outcome (death, discharge to institutional care, tracheostomy, or gastrostomy) for patients with long-term aspirin or anticoagulant use. Multivariable linear regression was used to evaluate length of hospital stay. Covariates included patient age, sex, comorbidities, primary payer, NIS-SAH severity scale, intracerebral hemorrhage, cerebral edema, herniation, modality of aneurysm repair, hospital bed size, and whether the hospital was a teaching hospital. Subgroup analyses exclusively evaluated patients treated surgically or endovascularly. RESULTS The study examined 11,549 hospital admissions. Both aspirin (2.1%, n = 245) and anticoagulant users (0.9%, n = 108) were significantly older and had a greater burden of comorbid disease (p < 0.001); severity of SAH was slightly lower in those with long-term aspirin use (p = 0.03). Neither in-hospital mortality (13.5% vs 12.6%) nor total complication rates (79.6% vs 80.0%) differed significantly by long-term aspirin use. Additionally, aspirin use was associated with decreased odds of a cardiac complication (OR 0.57, 95% CI 0.36%-0.91%, p = 0.02) or of venous thromboembolic events (OR 0.53, 95% CI 0.30%-0.94%, p = 0.03). Length of stay was significantly shorter (15 days vs 17 days [12.73%], 95% CI 5.22%-20.24%, p = 0.001), and the odds of a nonroutine discharge were lower (OR 0.63, 95% CI 0.48%-0.83%, p = 0.001) for aspirin users. In subgroup analyses, the benefits of aspirin were primarily noted in patients who underwent coil embolization; likewise, among patients treated endovascularly, the adjusted odds of a poor outcome were lower among long-term aspirin users (31.8% vs 37.4%, OR 0.63, 95% CI 0.42%-0.94%, p = 0.03). Although the crude rates of in-hospital mortality (19.4% vs 12.6%) and poor outcome (53.6% vs 37.6%) were higher for long-term anticoagulant users, in multivariable logistic regression models these variations were not significantly different (mortality: OR 1.36, 95% CI 0.89%-2.07%, p = 0.16; poor outcome: OR 1.09, 95% CI 0.69%-1.73%, p = 0.72). CONCLUSIONS In this nationwide study, neither long-term aspirin nor anticoagulant use were associated with differential mortality or complication rates after SAH. Aspirin use was associated with a shorter hospital stay and lower rates of nonroutine discharge, with these benefits primarily observed in patients treated endovascularly.