Adjunctive Use of Bone Growth Stimulation Increases Cervical Spine Fusion Rates in Patients at Risk for Pseudarthrosis

STUDY DESIGN

A prospective multicenter clinical trial (NCT03177473) was conducted with a retrospective cohort used as a control arm.

OBJECTIVE

The purpose of this study was to evaluate cervical spine fusion rates in subjects with risk factors for pseudarthrosis who received pulsed electromagnetic field (PEMF) treatment.

SUMMARY OF BACKGROUND DATA

Certain risk factors predispose patients to pseudarthrosis, which is associated with prolonged pain, reduced function, and decreased quality of life.

METHODS

Subjects in the PEMF group were treated with PEMF for 6 months postoperatively. The primary outcome measure was fusion status at the 12-month follow-up period. Fusion status was determined using anterior/posterior, lateral, and flexion/extension radiographs and computed tomography (without contrast).

RESULTS

A total of 213 patients were evaluated (PEMF, n=160; Control, n=53). At baseline, the PEMF group had a higher percentage of subjects who used nicotine ( P =0.01), had osteoporosis ( P <0.05), multi-level disease ( P <0.0001), and were >65 years of age ( P =0.01). The PEMF group showed over two-fold higher percentage of subjects that had ≥3 risk factors (n=92/160, 57.5%) compared with the control group (n=14/53, 26.4%). At the 12-month follow-up, the PEMF group demonstrated significantly higher fusion rates compared with the control (90.0% vs. 60.4%, P <0.05). A statistically significant improvement in fusion rate was observed in PEMF subjects with multi-level surgery ( P <0.0001) and high BMI (>30 kg/m 2 ; P =0.0021) when compared with the control group. No significant safety concerns were observed.

CONCLUSIONS

Adjunctive use of PEMF stimulation provides significant improvements in cervical spine fusion rates in subjects having risk factors for pseudarthrosis. When compared with control subjects that did not use PEMF stimulation, treated subjects showed improved fusion outcomes despite being older, having more risk factors for pseudarthrosis, and undergoing more complex surgeries.

Liposomal bupivacaine does not decrease postoperative opioid use or length of hospital stay in patients undergoing anterior cervical discectomy and fusion

BACKGROUND

Despite its widespread use, definitive data demonstrating the efficacy of liposomal bupivacaine (LB) is limited especially in patients undergoing anterior cervical discectomy and fusion (ACDF). Therefore, this investigation examined whether ACDF patients who received intra-operative LB (LB cohort) exhibited decreased post-operative opioid use and lengths of hospital stay (LOS) compared to ACDF patients who did not receive intra-operative LB (controls).

METHODS

Eighty-two patients who underwent primary ACDF by a single surgeon from 2016 to 2019 were identified from an institutional database. Fifty-nine patients received intra-operative LB while twenty-three did not. Patient characteristics, medical comorbidities, complications, post-operative opioid consumption, and LOS data were collected.

RESULTS

The LB cohort did not require fewer opioids on post-operative day (POD) 0, POD1, POD2, or throughout the hospital course after normalizing by LOS (total per LOS). The number of cervical vertebrae involved in surgery, but not LB use, predicted opioid consumption on POD0, POD1, and total per LOS. For every vertebral level involved, 242 additional morphine milligram equivalents (MME) were consumed on POD0, 266 additional MME were utilized on POD1, and 130 additional MME were consumed in total per LOS.

CONCLUSIONS

ACDF patients who received intra-operative LB did not require fewer post-operative opioids or exhibit a decreased LOS compared to controls. Patients whose procedures involved a greater number of cervical vertebrae were associated with greater opioid consumption on POD0, POD1, and total per LOS. ACDF patients, especially those who had a high number of vertebrae involved, may require alternative analgesia to LB.

Risk and treatment of symptomatic epidural hematoma after anterior cervical spine surgery: A retrospective clinical study

Symptomatic epidural hematoma (SEH) after anterior cervical spine surgery is very rare, but it has disastrous consequences for the patients. Timely diagnosis and evaluation can effectively reduce the sequelae of neurological deficit in SEH. The purpose of this study was to retrospectively analyze a subset of clinical data of SEH after anterior cervical spine surgery, and to investigate the risk factors and treatment experience of this serious complication.Neurological deterioration after anterior cervical spine surgery was detected in six patients. Epidural hematoma was confirmed by emergency cervical magnetic resonance imaging (MRI). The patients included five males and one female, with an average age of 56.7 ± 13.1 years (range 42-76 years). Three patients had a history of drinking and/or smoking. All of the patients were treated with nonsteroidal anti-inflammatory drugs (NSAIDs) preoperatively, but without anticoagulant drugs or pre-spinal surgery. The coagulation function was normal in all patients. Except for one patient, who had lower blood pressure (BP) during the operation and higher BP after the operation, the other patients had a normal level of BP during the pre-, intra-, and post-operation periods. The average time was 9.9 ± 6.7 hours (range, 2-19 hours) from the postoperative period to the initial neurological deficit and 6.3 ± 6.0 hours (range, 1.8-16.7 hours) from the initial deterioration to evacuation. Five patients underwent emergency evacuation, and one patient underwent conservative treatment. Four patients who underwent evacuation and one patient who received conservative treatment achieved neurological function recovery with an American Spinal Injury Association (ASIA) grade 2.4 ± 0.9 (range, 2-4 score) score at the last follow-up. One patient with confirmed arterial epidural hemorrhage during the evaluation showed no neurological function recovery at the last follow-up.Wide exposure of the epidural space and BP level during the perioperative period play an important role in the formation of SEH after anterior cervical spine surgery. Arterial epidural hematoma has serious consequences; therefore, early diagnosis and evaluation play an important role in the recovery from paralysis.

Risk factors for dysphagia after anterior cervical spine surgery: A meta-analysis

BACKGROUND

Dysphagia is a well-known complication following anterior cervical spine surgery. Although risk factors for dysphagia have been reported in the literature, they still remain controversial. This study aims to investigate the risk factors associated with dysphagia following anterior cervical spinal surgery.

METHODS

PubMed, EMBASE, and The Cochrane Library were searched up to June 2016 for studies examining dysphagia following anterior cervical spinal surgery. Risk factors associated with dysphagia were extracted. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for outcomes. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

RESULTS

The final analysis includes a total of 18 distinct studies. The pooled analysis reveals that there are significant differences in female gender (OR = 2.30, 95% CI: 1.76-2.99, P < 0.001), the use of anterior cervical plate (OR = 1.66, 95% CI: 1.05-2.62, P = 0.03), more than 1 surgical level (OR = 2.07, 95% CI: 1.62-2.66, P < 0.001), the upper surgical level at C3/4 (OR = 3.08, 95% CI: 1.44-6.55, P = 0.004), and the use of bone morphogenetic protein-2 (rhBMP-2) (OR = 5.52, 95% CI: 2.16-14.10, P < 0.001). However, no significant difference is found in revision surgery (OR = 1.67, 95% CI: 0.60-4.68, P = 0.33), the type of fusion (OR = 1.02, 95% CI: 0.62-1.67, P = 0.95), and cervical disc arthroplasty (OR = 1.37, 95% CI: 0.75-2.51, P = 0.30).

CONCLUSION

Female gender, the use of anterior cervical plate, more than 1 surgical level, the upper surgical level at C3/4, and the use of rhBMP-2 are the risk factors for dysphagia following anterior cervical spinal surgery. However, revision surgery, the type of fusion, and cervical disc arthroplasty are unassociated with dysphagia. Considering the limited number of studies, this conclusion should be interpreted cautiously, and larger scale studies are required.

Intraoperative Motor-Evoked Potential Disappearance versus Amplitude-Decrement Alarm Criteria During Cervical Spinal Surgery: A Long-Term Prognosis

Background and Purpose

We studied the clinical significance of amplitude-reduction and disappearance alarm criteria for transcranial electric muscle motor-evoked potentials (MEPs) during cervical spinal surgery according to different lesion locations [intramedullary (IM) vs. nonintramedullary (NIM)] by evaluating the long-term postoperative motor status.

Methods

In total, 723 patients were retrospectively dichotomized into the IM and NIM groups. Each limb was analyzed respectively. One hundred and sixteen limbs from 30 patients with IM tumors and 2,761 limbs from 693 patients without IM tumors were enrolled. Postoperative motor deficits were assessed up to 6 months after surgery.

Results

At the end of surgery, 61 limbs (2.2%) in the NIM group and 14 limbs (12.1%) in the IM group showed MEP amplitudes that had decreased to below 50% of baseline, with 13 of the NIM limbs (21.3%) and 2 of the IM limbs (14.3%) showing MEP disappearance. Thirteen NIM limbs (0.5%) and 5 IM limbs (4.3%) showed postoperative motor deficits. The criterion for disappearance showed a lower sensitivity for the immediate motor deficit than did the criterion for amplitude decrement in both the IM and NIM groups. However, the disappearance criterion showed the same sensitivity as the 70%-decrement criterion in IM (100%) and NIM (83%) surgeries for the motor deficit at 6 months after surgery. Moreover, it has the highest specificity for the motor deficits among diverse alarm criteria, from 24 hours to 6 months after surgery, in both the IM and NIM groups.

Conclusions

The MEP disappearance alarm criterion had a high specificity in predicting the long-term prognosis after cervical spinal surgery. However, because it can have a low sensitivity in predicting an immediate postoperative deficit, combining different MEP alarm criteria according to the aim of specific instances of cervical spinal surgery is likely to be useful in practical intraoperative monitoring.