Long-term survivability of surgical and nonsurgical management of spinal epidural abscess

BACKGROUND CONTEXT

Spinal epidural abscess (SEA) is a rare and life-threatening infection within the epidural space with significant functional impairment and morbidity. Active debate remains over whether to operate for SEAs, with limited existing data comparing the long-term survivability after surgical versus nonsurgical management.

PURPOSE

This study aims to determine the long-term survival of patients who underwent surgical and nonsurgical management for SEA.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

A total of 250 consecutive SEA patients.

OUTCOME MEASURES

Survival and mortality rates, complications.

METHODS

All patients treated at a tertiary medical center for a primary SEA from January 2000 to June 2020 are identified. Data collection is by retrospective chart review. Cox proportional hazards regression models are used for all survival analyses while controlling for potential confounding variables and with multiple testing corrections.

RESULTS

A total of 35 out of 250 patients died with an overall all-cause mortality of 14%. More than half of all deaths occurred within 90 days after treatment. The 90-day, 3-year, and 5-year survival rates are 92.8%, 89.2%, and 86.4%, respectively. Among surgery patients, the all-cause mortality was 13.07%, compared to 16.22% for medically-managed patients. Surgical treatment (decompression, fusion, debridement) significantly reduced the risk of death by 62.4% compared to medical therapy (p=.03), but surgery patients experienced a significantly longer mean length of stay (p=.01). Risk factors of short-term mortality included hypoalbuminemia (<3.5 g/dL), American Society of Anesthesiologists (ASA) 4+, and cardiac arrest. Risk factors of long-term mortality were immunocompromised state, elevated WBC count >12,000, sepsis, septic shock, ASA 4+, and cardiac arrest (p<.05). In terms of complications, surgically-managed patients experienced a higher proportion of deep vein thrombosis (p<.05).

CONCLUSIONS

The overall long-term survivability of SEA treatment is relatively high at (86% at 5-year) in this study. The following SEA mortality risk factors were identified: hypoalbuminemia (short-term), immunocompromised state (long-term), leukocytosis (long-term), sepsis and septic shock (long-term), ASA 4+ and cardiac arrest (overall). For primary SEA patients, surgical management may reduce mortality risk compared to nonsurgical management.

Factors Predisposing Patients to Non-Home Discharge After Surgery for Degenerative Cervical Myelopathy: A Retrospective Analysis

OBJECTIVE

The objective of this study is to evaluate factors associated with discharge to subacute care after surgery for degenerative cervical myelopathy (DCM).

DESIGN

This is a retrospective chart review of adults who underwent cervical spine surgery at a for DCM between 2014 and 2020 (n = 135).

RESULTS

Patients discharged to a subacute setting were older (68.1 +/- 8.6 vs. 64.1 years +/- 8.8; p = 0.01); more likely to be unmarried (55.8% vs. 33.7% married; p = 0.01); and more likely to have Medicare or Medicaid (83.7% vs. 65.9% private insurance; p = 0.03). than patients discharged home. A posterior surgical approach was associated with discharge to a subacute setting (62.8% vs. 43.5% anterior approach; p = 0.04). 87.8% of patients discharged to a subacute setting required moderate or maximum assistance for bed mobility vs. 26.6% of patients discharged home (p < 0.0001).Compared to patients discharged home, patients discharged to a subacute setting ambulated a shorter distance in their first Physical Therapy Evaluation after surgery (8.9 meters +/- 35.8 vs. 53.7 meters +/- 61.78 in the home discharge group; p < 0.0001).

CONCLUSION

Analysis of these factors may guide discussions about patient expectations for postoperative discharge placement.

Factors Associated With the Rate of Recovery After Cervical Decompression Surgery for Degenerative Cervical Myelopathy: A Retrospective Analysis

Introduction Degenerative cervical myelopathy (DCM) is a debilitating spinal condition with a wide variety of symptoms that can differ greatly among individuals. Common symptoms include numbness, extremity weakness, loss of balance, and gait instability. Decompression surgeries are commonly indicated for the treatment of DCM with varying outcomes reported in the literature. However, there is little evidence on the rate of recovery defined as the time until improvement in symptoms such as numbness, balance, and strength after surgery for DCM. The purpose of this study was to determine the rate of neurological recovery after surgery for DCM and its subsequent association with various risk factors to guide clinicians while providing care and improve patient education. Methods This study was a retrospective case series (n=180 patients) examining patients who underwent cervical decompression surgery for DCM. All patients had a clinical presentation of DCM, were diagnosed with DCM, had radiographic degenerative changes and cervical stenosis, and received surgical management from 2010 to 2020 in a tertiary hospital system. Data recorded included age, smoking status, duration of pre-operative symptoms, preoperative and postoperative pain, and postoperative rate of recovery (days until improvement) in numbness, upper extremity strength, and balance. Results Patients (n=180) had an average age of 65.7 years (SD ±9.2 years, range 43-93 years). The mean ± standard deviation for the rate of recovery (days until improvement) in numbness, upper extremity strength, and balance was 84.5 ± 94.4 days, 50.6 ± 42.8 days, and 60.4 ± 69.9 days, respectively. There was only a marginally significant association between the rate of recovery for numbness after surgery and patient age (p=0.053). The average rate of recovery in numbness for patients older than 60 years was significantly longer than those younger than 60 years (99.3 versus 60.2 days). Preoperative smoking status was significantly associated with persistent moderate to severe pain (p=0.032) within the six-month postoperative period. No significant correlations were seen between the rate of recovery for balance or strength and patient age or preoperative duration of symptoms. Conclusion There was great variability in the rate of recovery for postoperative symptoms after surgery for DCM. A longer time for improvement in postoperative numbness was only marginally correlated with the increased patient age after surgery for DCM. There was no correlation found between strength or balance recovery times and patient age. Smoking status was associated with moderate to severe postoperative pain after surgery for DCM. Furthermore, the duration of preoperative symptoms was not associated with improvement in postoperative symptoms after surgery for DCM. More research is needed to determine factors impacting the rate of recovery after surgery for DCM.

Single-Site Retrospective Assessment of Surgical Outcomes in Non-Ambulatory Patients with Degenerative Cervical Myelopathy

STUDY DESIGN

A retrospective study of surgical outcomes in patients with degenerative cervical myelopathy (DCM).

OBJECTIVE

To better characterize outcomes following cervical decompression in those with severe, non-ambulatory forms of DCM.

SUMMARY OF BACKGROUND DATA

DCM represents a collection of age-related degenerative processes of the cervical spine that can result in motor, sensory, and autonomic dysfunction, leading to significant reductions in quality of life. Individuals with severe, non-ambulatory forms of DCM are often treated with spinal decompression although the extent of neurological improvement for this patient population is unclear.

METHODS

A retrospective analysis of 48 non-consecutive non-ambulatory patients who underwent cervical decompression surgery between January 2007 and December 2018. Paired t tests and Wilcoxon signed rank tests were used to compare Nurick grade and modified Japanese Orthopedic Association (mJOA) score before and after surgery. Patient demographics, operative details, and postsurgical complications were analyzed using descriptive statistics.

RESULTS

Patients experienced significant improvements in both Nurick grade and mJOA score following cervical decompression surgery. The mean Nurick grade improved from 4.10 ± 0.31 to 2.21 ± 0.82 (P < 0.001, paired t test; 95% confidence interval [CI] -2.08 to -1.71), while the mean mJOA score improved from 10.58 ± 1.51 to 13.60 ± 1.58 (P < 0.001, paired t test; 95% CI 2.59-3.45). The average follow-up duration was 2.50 ± 1.83 years. Following surgery, 44 of the 48 patients in the study gained the ability to ambulate without the aid of a walking frame or someone else's assistance.

CONCLUSION

This study demonstrated that patients with severe forms of DCM experienced significant improvement in neurological function following cervical decompression surgery. These improvements indicate that cervical decompression surgery is effective in this patient population and has the potential to improve neurological status.Level of Evidence: 3.

Cervical fusion for treatment of degenerative conditions: development of appropriate use criteria

BACKGROUND CONTEXT

High quality evidence is difficult to generate, leaving substantial knowledge gaps in the treatment of spinal conditions. Appropriate use criteria (AUC) are a means of determining appropriate recommendations when high quality evidence is lacking.

PURPOSE

Define appropriate use criteria (AUC) of cervical fusion for treatment of degenerative conditions of the cervical spine.

STUDY DESIGN/SETTING

Appropriate use criteria for cervical fusion were developed using the RAND/UCLA appropriateness methodology. Following development of clinical guidelines and scenario writing, a one-day workshop was held with a multidisciplinary group of 14 raters, all considered thought leaders in their respective fields, to determine final ratings for cervical fusion appropriateness for various clinical situations.

OUTCOME MEASURES

Final rating for cervical fusion recommendation as either "Appropriate," "Uncertain" or "Rarely Appropriate" based on the median final rating among the raters.

METHODS

Inclusion criteria for scenarios included patients aged 18 to 80 with degenerative conditions of the cervical spine. Key modifiers were defined and combined to develop a matrix of clinical scenarios. The median score among the raters was used to determine the final rating for each scenario. The final rating was compared between modifier levels. Spearman's rank correlation between each modifier and the final rating was determined. A multivariable ordinal regression model was fit to determine the adjusted odds of an "Appropriate" final rating while adjusting for radiographic diagnosis, number of levels and symptom type. Three decision trees were developed using decision tree classification models and variable importance for each tree was computed.

RESULTS

Of the 263 scenarios, 47 (17.9 %) were rated as rarely appropriate, 66 (25%) as uncertain and 150 (57%) were rated as appropriate. Symptom type was the modifier most strongly correlated with the final rating (adjusted ρ2 = 0.58, p<.01). A multivariable ordinal regression adjusting for symptom type, diagnosis, and number of levels and showed high discriminative ability (C statistic = 0.90) and the adjusted odds ratio (aOR) of receiving a final rating of "Appropriate" was highest for myelopathy (aOR, 7.1) and radiculopathy (aOR, 4.8). Three decision tree models showed that symptom type and radiographic diagnosis had the highest variable importance.

CONCLUSIONS

Appropriate use criteria for cervical fusion in the setting of cervical degenerative disorders were developed. Symptom type was most strongly correlated with final rating. Myelopathy or radiculopathy were most strongly associated with an "Appropriate" rating, while axial pain without stenosis was most associated with "Rarely Appropriate."

Detection of postoperative neurologic deficits using somatosensory-evoked potentials alone during posterior cervical laminoplasty

BACKGROUND CONTEXT

The use of neurophysiologic monitoring during anterior and posterior cervical decompression procedures in patients with spondylotic myelopathy remains controversial. The ideal neurophysiologic monitoring modality of choice is also highly debated.

PURPOSE

The purpose of this study was to evaluate the utility of neurophysiologic monitoring with only somatosensory-evoked potentials (SSEPs) in a consecutive series of laminoplasty procedures with regard to the detection of new postoperative neurologic deficits.

STUDY DESIGN

Retrospective case series.

PATIENT SAMPLE

Eighty consecutive patients who underwent a posterior cervical laminoplasty were reviewed.

OUTCOME MEASURES

We analyzed intraoperative SSEP amplitude and latency changes from baseline with regard to the development of new postoperative neurologic deficits.

METHODS

We retrospectively reviewed 80 patients who underwent a posterior cervical "open-door" laminoplasty with a standard SSEP neurophysiologic monitoring protocol. Intraoperative SSEP amplitude and latency changes from baseline ("alerts") were analyzed with regard to the development of new postoperative neurologic deficits.

RESULTS

Baseline SSEP values were obtained in all patients. There were five (6%) procedures that had SSEP alerts. All alerts occurred shortly after the lamina was hinged open. Four patients with SSEP alerts developed new postoperative neurologic deficits, including three unilateral upper extremity motor and sensory deficits and one complete spinal cord injury. In the immediate postoperative period, our experience with SSEP monitoring demonstrated 4 true-positive, 75 true-negative, and 1 false-positive monitoring results.

CONCLUSIONS

In this series of laminoplasty procedures, SSEP neurophysiologic monitoring had a high sensitivity and specificity for predicting new neurologic deficits in the early postoperative period. Somatosensory-evoked potentials are an effective tool for spinal cord monitoring when performing a posterior cervical laminoplasty procedure.

Steroids and risk factors for airway compromise in multilevel cervical corpectomy patients: a prospective, randomized, double-blind study

STUDY DESIGN

Prospective, randomized, double-blind study.

OBJECTIVE

To evaluate intravenous corticosteroids in preventing delayed extubation after multilevel corpectomy and strut graft reconstructive procedures and to identify risk factors for delayed extubation in these patients.

SUMMARY OF BACKGROUND DATA

We performed a prospective, randomized double-blind study in patients undergoing multilevel cervical corpectomy procedures. Our hypothesis was that high-dose perioperative steroids would decrease edema and thus decrease the incidence of delayed extubation.

METHODS

We studied patients undergoing 2- or 3-level anterior cervical corpectomy procedures with anterior strut graft reconstruction. Sixty-six patients were randomized to receive 3 doses of either intravenous dexamethasone (n = 35) or saline (n = 31). The first dose was given before the incision, with subsequent doses given 8 and 16 hours later. Patients remained intubated until postoperative day 1, at which time a cuff leak test was performed by the anesthesiology attending. If a leak was present, the patient was extubated. If not, the test was repeated each postoperative day until a leak was present, indicating a patent airway.

RESULTS

Five of 35 (14%) in the steroid group and 6 of 31 (19%) in the saline group required delayed extubation (P = 0.22). There were no statistical differences in preoperative parameters of age, gender, diagnosis, smoking history, BMI, number of operative levels, or preoperative American Society of Anesthesiologists rating between the 2 groups. Similarly there were no differences between the groups for duration of anesthesia, intraoperative colloids or crystalloids, intraoperative blood loss, or intraoperative urine output. The data for both groups were pooled to evaluate risk factors for delayed extubation. The only statistically significant risk factor for delayed extubation in this study was female gender (P = 0.0001).

CONCLUSION

Based on our data, we cannot recommend intravenous dexamethasone for prevention of delayed extubation after multilevel anterior cervical corpectomy and strut grafting procedures.

Weight loss in overweight and obese patients following successful lumbar decompression

BACKGROUND

Neurogenic claudication secondary to lumbar stenosis is often cited by overweight and obese patients as a factor limiting their ability to lose weight. Many patients believe that they will be able to increase their activity and subsequently lose weight following relief of symptoms. The objective of this study was to evaluate weight loss in overweight and obese patients who obtained substantial pain relief after lumbar decompression surgery for spinal stenosis.

METHODS

Changes in the body weight and body mass index of overweight and obese patients after lumbar decompression surgery were assessed at a mean of 34.4 months postoperatively. Sixty-three patients (thirty-seven men and twenty-six women with a mean age of 53.4 years) were included in the study. Preoperative and postoperative body weight and body mass indices were calculated, and Zurich Claudication Questionnaire (ZCQ) Symptom Severity and Physical Function scores were obtained.

RESULTS

The ZCQ Symptom Severity and Physical Function scores significantly improved, by a mean of 56.4% and 53.0%, respectively. At the time of follow-up, both the mean body weight and the mean body mass index significantly increased, by 2.48 kg and 0.83 kg/m(2), respectively. Overall, 35% of the patients gained >or=5% of their preoperative body weight, 6% of the patients lost >or=5% of their preoperative body weight, and 59% remained within 5% of their preoperative body weight.

CONCLUSIONS

The majority of overweight and obese patients maintain or increase their body weight and body mass index following successful lumbar decompression surgery. Substantial relief of symptoms and functional improvements do not appear to help overweight or obese patients to lose weight. This suggests that obesity is an independent disease and not simply a function of symptomatic spinal stenosis, and patients should be counseled regarding these expectations.

Risk factors for dysphagia after anterior cervical spine surgery: a two-year prospective cohort study

BACKGROUND CONTEXT

Severe and disabling dysphagia is a relatively uncommon complication of anterior cervical spine surgery. However, the incidence of dysphagia ranges widely (2% to 60%). Furthermore, risk factors that contribute to the development of dysphagia have not been well identified.

PURPOSE

The purpose of this study was to evaluate the prevalence of dysphagia after anterior cervical spine surgery, and to identify any risk factors associated with increased dysphagia.

STUDY DESIGN

This study is a prospective cohort study designed to evaluate the prevalence of dysphagia at 1, 2, 6, 12, and 24 months. Patients were prospectively interviewed at 1, 2, 6, 12, and 24 months regarding the presence and subjective severity of dysphagia.

PATIENT SAMPLE

Between the period of 1999 and 2002, 348 cervical spine surgeries were performed using the anterior Smith Robinson approach. 310 of these patients were available for 2-year follow-up.

OUTCOMES MEASURE

Using the dysphagia grading system defined by Bazaz et al. (Spine 2002), we prospectively evaluated patients' postoperative dysphagia.

METHODS

The presence and severity of dysphagia were reported during the telephone interviews performed at 1, 2, 6, 12, and 24 months after the procedure. Proportion analysis (chi-square or a Fisher Exact Test), prevalence ratios, and 95% confidence intervals were used to compare the prevalence of dysphagia with age, gender, type of surgery (eg, discectomy vs. corpectomy, primary vs. revision), use of instrumentation, number and location of surgical levels.

RESULTS

The overall prevalences for dysphagia at 1, 2, 6, 12, and 24 months were 54.0%, 33.6%, 18.6%, 15.2%, and 13.6%. The prevalence of dysphagia was found to be significantly higher in women (18.3%) than men (9.9%) 2 years after the surgery. Revision surgery patients (27.7%) also had a significantly higher prevalence of dysphagia than primary surgery (11.3%) patients 2 years after the surgery. Patients who underwent more than two-level surgery (19.3%) also had significantly higher rates of dysphagia 2 years after their procedures than patients who had two or less levels (9.7%) operated on.

CONCLUSION

Overall the incidence of dysphagia 2 years after anterior cervical spine surgery was 13.6%. Risk factors for long-term dysphagia after anterior cervical spine surgery include gender, revision surgeries, and multilevel surgeries. The use of instrumentation, higher levels, or corpectomy versus discectomy did not significantly increase the prevalence of dysphagia.

Risk Factors for Delayed Extubation After Single-stage, Multi-level Anterior Cervical Decompression and Posterior Fusion

Airway difficulties after single-stage, multilevel anterior and posterior cervical surgery are potentially life-threatening complications. Although extubation delays can occur, overnight intubation can reduce the risk of postoperative airway emergencies. Our protocol was as follows: all patients were kept intubated overnight in an intensive care unit and examined by the intensive care unit staff each morning. Readiness for extubation was based on the cuff-leak test, and extubation done on patients beyond the first postoperative day was considered delayed. Eleven patients were extubated on the first postoperative day (group 1), and 11 extubated beyond day 1 (group 2). No airway emergencies occurred. Patient factors-age, weight, smoking, medical comorbidities, American Society of Anesthesiologist class-were not significantly related to extubation delay. There were no differences between groups in the number of anterior and posterior levels or anterior and posterior operative times. Delayed extubation was significantly related to total operative time (8.2 hours vs. 10.6 hours), volume of crystalloid replacement (3,627 cm3 vs. 6,218 cm3) and intraoperative blood transfused (0.7 units vs. 3.1 units); approaching significance was increased blood loss (1,238 mL vs. 2,820 mL). We have found intraoperative factors-operative time, crystalloid volume, blood loss and replacement-rather than patient characteristics, to be risk factors for delayed extubation. Good communication with anesthesia staff and careful attention to postoperative airway management is essential after single-stage, multilevel anterior cervical decompression and posterior fusion.

Influence of Anterior Cervical Plate Design on Dysphagia

OBJECTIVE

To compare the incidence, prevalence, and rate of improvement of dysphagia in patients undergoing anterior cervical spine surgery with two different anterior instrumentation designs.

METHODS

The study subjects were 156 consecutive patients undergoing anterior cervical spine surgery with plate fixation. We compared the incidence of dysphagia among the two different plate groups both produced by the same manufacturer (Medtronic Danek); the Atlantis plate has thicker and wider plate dimensions than the Zephir plate. Dysphagia evaluations were performed prospectively by telephone interviews at 1, 2, 6, 12, and 24 months following the procedure. Risk factors such as gender, revision surgery, and number of surgical levels were compared between the groups and were not statistically different.

RESULTS

Overall incidences of dysphagia were 49%, 37%, 20%, 15.4%, and 11% at 1, 2, 6, 12, and 24 months, respectively. Severe and disabling dysphagia is reported to be a relatively uncommon complication of anterior cervical surgery. However, a significant number of patients report mild to moderate discomfort including double-swallowing and catching sensation. Except at the 2-month follow-up point, the Atlantis plate group had higher incidences of dysphagia than the Zephir group at all time points (57% vs 50%, 36% vs 4%, 23% vs 14%, 17% vs 7%, 14% vs 0% at 1, 2, 6, 12, and 24 months, respectively). The Atlantis plate group had a 14% incidence of dysphagia at 2 years compared with the Zephir group, which had a 0% incidence at 2 years (P < 0.04). For primary surgeries, there was a higher incidence of dysphagia at all time points in the Atlantis group when compared with the Zephir group (58% vs 43%, 35% vs 30%, 22% vs 10%, 17% vs 0%, and 13% vs 0% at 1, 2, 6, 12, and 24 months, respectively) (P < 0.04 at 1 year). A regression analysis was performed. The resulting formulas predict the permanent rate of dysphagia for the Atlantis group is 13.6% and for the Zephir group is 3.58%.

CONCLUSIONS

The use of a smaller and smoother profile plate such as the Zephir does reduce the incidence of dysphagia as compared with a slightly larger and less smooth plate such as the Atlantis.

Histopathologic analysis of failed vascularized fibular grafts in femoral head osteonecrosis

Salient histopathological features in 13 failed free vascularized fibular autografts implanted for osteonecrosis of the femoral head are documented. Of particular clinical and/or biomechanical relevance are 1-2-mm-thick seams of viable lamellar bone bonded circumferentially to anatomically intact but necrotic graft cortices, which appear to preclude their revascularization and remodeling. Surrounding the grafts are 3-6-mm-thick rings of reactive bone, fused in many sites (average approximately 54%) to the osseous seams. They consist of a layer of sclerotic cortical-like bone melded with an outer layer of thickened cancellous bone. This remodeled reactive bone, largely the result of drilling, appears to buttress the grafts structurally and by inference, functionally. Operative failures in all but one case are attributed primarily to collapse of the necrotic, fractured superior subtending segment of the graft and of the subchondral plate secondary to size and progression of the osteonecrosis and superimposed osteoarthrosis. Morphological integrity of grafts elsewhere and perifibular reactive sclerotic bone remain unimpaired for up to 5 1/2 years. The salutary features of vascularized autografts would appear to give them a decided advantage over their nonvascularized counterpart.