John W. German

Complications of cranioplasty following decompressive craniectomy: analysis of 62 cases

OBJECT Decompressive craniectomy is a potentially life-saving procedure used in the treatment of medically refractory intracranial hypertension, most commonly in the setting of trauma or cerebral infarction. Once performed, surviving patients are obligated to undergo a second procedure for cranial reconstruction. The complications following cranial reconstruction are not well described in the literature and may very well be underreported. A review of the complications would suggest measures to improve the care of these patients. METHODS A retrospective chart review was undertaken of all patients who had undergone cranioplasty during a 7-year period. Demographic data, indications for craniectomy, as well as preoperative, intraoperative, and postoperative parameters following cranioplasty, were recorded. Perioperative and postoperative complications were also recorded. Patients were classified as having no complications, any complications, and complications requiring reoperation. The groups were compared to identify risk factors predictive of poor outcomes. RESULTS The authors identified 62 patients who had undergone cranioplasty. The immediate postoperative complication rate was 34%. Of these, 46 patients did not require reoperation and 16 did. Of those requiring reoperation, 7 were due to infection, 2 from wound breakdown, 2 from intracranial hemorrhage, 3 from bone resorption, and 1 from a sunken cranioplasty, and 1 patients cranioplasty procedure was prematurely ended due to intraoperative hypotension and bradycardia. The only factor statistically associated with need for reoperation was the presence of a bifrontal cranial defect (bifrontal: 8 [67%] of 12, requiring reoperation; unilateral: 8 [16%] of 49 requiring reoperation; p < 0.01) CONCLUSIONS Cranioplasty following decompressive craniectomy is associated with a high complication rate. Patients undergoing a bifrontal craniectomy are at significantly increased risk for postcranioplasty complications, including the need for reoperation.

Perioperative results following lumbar discectomy: comparison of minimally invasive discectomy and standard microdiscectomy

OBJECT Minimally invasive lumbar discectomy is a refinement of the standard open microsurgical discectomy technique. Proponents of the minimally invasive technique suggest that it improves patient outcome, shortens hospital stay, and decreases hospital costs. Despite these claims there is little support in the literature to justify the adoption of minimally invasive discectomy over standard open microsurgical discectomy. In the present study, the authors address some of these issues by comparing the short-term outcomes in patients who underwent first time, single-level lumbar discectomy at L3-4, L4-5, or L5-S1 using either a minimally invasive percutaneous, muscle splitting approach or a standard, open, muscle-stripping microsurgical approach. METHODS A retrospective chart review of 172 patients who had undergone a first-time, single-level lumbar discectomy at either L3-4, L4-5, or L5-S1 was performed. Perioperative results were assessed by comparing the following parameters between patients who had undergone minimally invasive discectomy and those who received standard open microsurgical discectomy: length of stay, operative time, estimated blood loss, rate of cerebrospinal fluid leak, post-anesthesia care unit narcotic use, need for a physical therapy consultation, and need for admission to the hospital. RESULTS Forty-nine patients underwent minimally invasive discectomy, and 123 patients underwent open microsurgical discectomy. At baseline the groups did differ significantly with respect to age, but did not differ with respect to height, weight, sex, body mass index, level of radiculopathy, side of radiculopathy, insurance status, or type of preoperative analgesic use. No statistically significant differences were identified in operative time, rate of cerebrospinal fluid leak, or need for a physical therapy consultation. Statistically significant differences were identified in length of stay, estimated blood loss, postanesthesia care unit narcotic use, and need for admission to the hospital. CONCLUSIONS In this retrospective study, patients who underwent minimally invasive discectomy were found to have similar perioperative results as those who underwent open microsurgical discectomy. The differences, although statistically significant, are of modest clinical significance.

A comparison of hinge craniotomy and decompressive craniectomy for the treatment of malignant intracranial hypertension: early clinical and radiographic analysis

OBJECT Hinge craniotomy (HC) has recently been described as an alternative to decompressive craniectomy (DC). Although HC may obviate the need for cranial reconstruction, an analysis comparing HC to DC has not yet been published. METHODS A retrospective review was conducted of 50 patients who underwent cranial decompression (20 with HC, 30 with DC). Baseline demographics, neurological examination results, and underlying pathology were reviewed. Clinical outcome was assessed by length of ventilatory support, length of intensive care unit stay, and survival at discharge. Control of intracranial hypertension was assessed by average daily intracranial pressure (ICP) for the duration of ICP monitoring and an ICP therapeutic intensity index. Radiographic outcomes were assessed by comparing preoperative and postoperative CT scans for: 1) Rotterdam score; 2) postoperative volume of cerebral expansion; 3) presence of uncal herniation; 4) intracerebral hemorrhage; and 5) extraaxial hematoma. Postoperative CT scans were analyzed for the size of the craniotomy/craniectomy and magnitude of extracranial herniation. RESULTS No significant differences were identified in baseline demographics, neurological examination results, or Rotterdam score between the HC and DC groups. Both HC and DC resulted in adequate control of ICP, as reflected in the average ICP for each group of patients (HC = 12.0 +/- 5.6 mm Hg, DC = 12.7 +/- 4.4 mm Hg; p > 0.05) at the same average therapeutic intensity index (HC = 1.2 +/- 0.3, DC = 1.2 +/- 0.4; p > 0.05). The need for reoperation (3 [15%] of 20 patients in the HC group, 3 [10%] of 30 patients in the DC group; p > 0.05), hospital survival (15 [75%] of 20 in the HC group, 21 [70%] of 30 in the DC group; p > 0.05), and mean duration of both mechanical ventilation (9.0 +/- 7.2 days in the HC group, 11.7 +/- 12.0 days in the DC group; p > 0.05) and intensive care unit stay (11.6 +/- 7.7 days in the HC group, 15.6 +/- 15.3 days in the DC group; p > 0.05) were similar. The difference in operative time for the two procedures was not statistically significant (130.4 +/- 71.9 minutes in the HC group, 124.9 +/- 63.3 minutes in the DC group; p > 0.05). The size of the cranial defect was comparable between the 2 groups. Postoperative imaging characteristics, including Rotterdam score, also did not differ significantly. Although a smaller volume of cerebral expansion was associated with HC (77.5 +/- 54.1 ml) than DC (105.1 +/- 65.1 ml), this difference was not statistically significant. CONCLUSIONS Hinge craniotomy appears to be at least as good as DC in providing postoperative ICP control and results in equivalent early clinical outcomes.

Analysis of the subdural evacuating port system for the treatment of subacute and chronic subdural hematomas

OBJECT The subdural evacuating port system (SEPS; Medtronic, Inc.) is a minimally invasive means of draining subacute or chronic subdural fluid collections. The purpose of this study was to examine a single institutions results with the SEPS. METHODS A retrospective chart review was undertaken for all patients who underwent SEPS drainage of subdural collections. Demographic and radiographic characteristics were evaluated. Both pre- and post-SEPS CT studies were analyzed to determine the volume of subdural collection and midline shift. Hospital charts were reviewed for SEPS output, and periprocedural complications were noted. RESULTS were classified as a success (S) or failure (F) based on the need for further subdural drainage procedures. Groups were then compared to identify factors predictive of success. Results Eighty-five subdural collections were treated in 74 patients (unilateral collections in 63 patients and bilateral in 11). Sixty-three collections (74%) were successfully drained. In a comparison of the success and failure groups, there were no statistically significant differences (p < 0.05) in the mean age pre-SEPS, Glasgow Coma Scale score, presenting symptoms, underlying coagulopathy or use of anticoagulation/antiplatelet agents, laterality of SDH, pre-SEPS subdural volume or midline shift, or any of the measurements used to characterize SEPS placement. There were a greater number of male patients in the success group (45 [82%] of 55 patients vs 11 [58%] of 19 patients; p = 0.04). The only statistically significant (p < 0.05) factor predictive of success was the radiographic appearance of the subdural collection. More hypodense collections were successfully treated (32 [51%] of 63 collections vs 4 [18%] of 22 collections; p = 0.005), whereas mixed density collections were more likely to fail SEPS treatment (S: 11 [17%] of 63 collections vs F: 14 [64%] of 22 collections; p < 0.00001). In the success group, the percentage of the collection drained after SEPS was greater (S: 47.1 ± 32.8% vs F: 19.8 ± 28.2%; p = 0.001) and a larger output was drained (S: 190.7 ± 221.5 ml vs F: 60.2 ± 63.3 ml; p = 0.001). In the patients with available but delayed scans (≥ 30 days since SEPS placement), the residual subdural collection following successful SEPS evacuation was nearly identical to that remaining after open surgical evacuation in the failure group. In 2 cases (2.4% of total devices used), SEPS placement caused a new acute subdural component, necessitating emergency evacuation in 1 patient. CONCLUSIONS The SEPS is a safe and effective treatment option for draining subacute and chronic SDHs. The system can be used quickly with local anesthesia only, making it ideal in elderly or sick patients who might not tolerate the physiological stress of a craniotomy under general anesthesia. Computed tomography is useful in predicting which subdural collections are most amenable to SEPS drainage. Specifically, hypodense subdural collections drain more effectively through an SEPS than do mixed density collections. Although significant bleeding after SEPS insertion was uncommon, 1 patient in the series required urgent surgical hematoma evacuation due to iatrogenic injury.

Beta blockers exposure and traumatic brain injury: a literature review

Traumatic brain injury (TBI) continues to carry a significant public health burden and is anticipated to worsen worldwide over the next century. Recently the authors of several articles have suggested that exposure to beta blockers may improve mortality rates following TBI. The exact mechanism through which beta blockers mediate this effect is unknown. In this paper, the authors review the literature regarding the safety of beta blockers in patients with TBI. The findings of several recent retrospective cohort studies are examined and implications for future investigation are discussed. Future questions to be addressed include: the specific indications for the use of beta blockers in patients with TBI, the optimal type and dose of beta blocker given, the end point of beta blocker therapy, and the safety of beta blockers in cases of severe TBIs.

Minimally invasive approach for the treatment of intradural spinal pathology

OBJECT A wide variety of spinal intradural pathology traditionally has been treated from a midline posterior laminectomy using standard microsurgical techniques. This approach has been successful in treating the pathology; however, it carries a risk of postoperative complications including CSF leakage, wound infection, and spinal instability. The authors describe a minimally invasive surgical (MIS) approach to treating spinal intradural pathology with a low rate of postoperative complications. METHODS Through a retrospective review of a prospectively collected surgical database, the authors identified 26 patients who underwent 27 surgeries via an MIS approach for intradural pathology of the spine. Using a tubular retractor system and an operative microscope, the authors were able to treat all patients with a unilateral, paramedian, and muscle-splitting technique. They then collected data regarding operative blood loss, length of stay, imaging characteristics, and outcomes. RESULTS Eight cervical, 8 thoracic, and 11 lumbar intradural pathological entities, which included 14 oncological lesions, 4 Chiari I malformations, 4 arachnoid cysts, 3 tethered cords, 1 syrinx, and 1 chronic visceral pain, were treated via an MIS approach. The average blood loss was 197 ml and the average hospital stay was 3 days. One patient had to return to the operating room for noninfectious wound dehiscence. One patient required reoperation 18 months after the initial surgery for recurrence of the initial pathology. There was no CSF leak, no infection, and no spinal instability associated with the initial surgery on follow-up. CONCLUSIONS Intradural spinal pathology can be safely and effectively treated with MIS approaches without an increased risk of neurological injury. This approach may also offer a reduced postoperative length of stay, risk of CSF leak, and risk of future spinal instability.

A comparison of minimally invasive posterior cervical decompression and open anterior cervical decompression and instrumented fusion in the surgical management of degenerative cervical myelopathy

OBJECTIVE Minimally invasive posterior cervical decompression (miPCD) has been described in several case series with promising preliminary results. The object of the current study was to compare the clinical outcomes between patients undergoing miPCD with anterior cervical discectomy and instrumented fusion (ACDFi). METHODS A retrospective study of 74 patients undergoing surgery (45 using miPCD and 29 using ACDFi) for myelopathy was performed. Outcomes were categorized into short-term, intermediate, and long-term follow-up, corresponding to averages of 1.7, 7.7, and 30.9 months, respectively. Mean scores for the Neck Disability Index (NDI), neck visual analog scale (VAS) score, SF-12 Physical Component Summary (PCS), and SF-12 Mental Component Summary (MCS) were compared for each follow-up period. The percentage of patients meeting substantial clinical benefit (SCB) was also compared for each outcome measure. RESULTS Baseline patient characteristics were well-matched, with the exception that patients undergoing miPCD were older (mean age 57.6 ± 10.0 years [miPCD] vs 51.1 ± 9.2 years [ACDFi]; p = 0.006) and underwent surgery at more levels (mean 2.8 ± 0.9 levels [miPCD] vs 1.5 ± 0.7 levels [ACDFi]; p < 0.0001) while the ACDFi patients reported higher preoperative neck VAS scores (mean 3.8 ± 3.0 [miPCD] vs 5.4 ± 2.6 [ACDFi]; p = 0.047). The mean PCS, NDI, neck VAS, and MCS scores were not significantly different with the exception of the MCS score at the short-term follow-up period (mean 46.8 ± 10.6 [miPCD] vs 41.3 ± 10.7 [ACDFi]; p = 0.033). The percentage of patients reporting SCB based on thresholds derived for PCS, NDI, neck VAS, and MCS scores were not significantly different, with the exception of the PCS score at the intermediate follow-up period (52% [miPCD] vs 80% [ACDFi]; p = 0.011). CONCLUSIONS The current report suggests that the optimal surgical strategy in patients requiring dorsal surgery may be enhanced by the adoption of a minimally invasive surgical approach that appears to result in similar clinical outcomes when compared with a well-accepted strategy of ventral decompression and instrumented fusion. The current results suggest that future comparative effectiveness studies are warranted as the miPCD technique avoids instrumented fusion.

Management of Thoracic Spine Injuries Part I: Thoracic Spine Anatomy and Stability

This article is the first of two parts. Thoracic spinal column injuries, although relatively uncommon, often are associated with significant visceral injuries and a high incidence of complete spinal cord injuries. For the purpose of this article, thoracic spinal column injuries are defined as injuries occurring between T2 and T11, although we discuss the anatomy of the entire thoracic spine (T1–T12). We emphasize that the cervicothoracic and thoracolumbar junctions, while including thoracic spinal levels, have unique anatomic and biomechanical features that affect management decisions and are distinct from other thoracic vertebrae. Part I of this article addresses the epidemiology of thoracic spinal column and spinal cord injuries, the unique anatomic features of the thoracic spine, the biomechanics of the thoracic spine, and the initial evaluation of thoracic spine injury. Part II will address the evaluation of spinal stability, the surgical decision-making process, and an overview of thoracic spinal surgical approaches. Epidemiology of Injuries to the Thoracic Spinal Column and Spinal Cord The annual incidence of traumatic spinal cord injury in the United States is approximately 40 per 1 million population. Mortality following spinal cord injury is significant, with a reported fatality rate as high as 48%. Because of the severity of concomitant injuries, most deaths occur before the patient reaches the hospital. The most common modes of traumatic spinal cord injury are motor vehicle collisions, falls, workrelated accidents, and recreational activity-related accidents. The latter category is the fastest-growing group of spinal cord injuries. Spinal cord injuries occur four times more commonly in young, Caucasian men than in any other group. Spinal cord injuries are classified according to the patient’s level of functioning, which is defined as the last spinal cord segment with normal motor and sensory function. Accordingly, patients are considered paraplegic if they demonstrate neurologic dysfunction below the T1 level and quadriplegic if the neurologic deficit includes a segment at or above T1. Injuries also are classified as complete or incomplete. Complete injuries are defined by absence of any motor, sensory, or reflex function below the level of injury, whereas injuries in which the patient has preserved some function are defined as incomplete. Many thoracic spinal cord injuries are misclassified, because the initial assessment of patients with these injuries often is limited by the presence of concurrent multiorgan Management of Thoracic Spine Injuries