Postoperative Measurement of the Retropharyngeal Space Predicts the Risk of Dysphagia After Anterior Cervical Diskectomy and Fusion

Neurosurgery 94:1116–1121, 2024

Postoperative dysphagia is a common complication of anterior cervical diskectomy and fusion (ACDF), although its pathophysiology remains poorly understood. Patients with severe dysphagia may suffer from serious complications such as aspiration pneumonia, in addition to difficulty with oral intake or malnutrition; therefore, a prompt indicator for postoperative management would be helpful. We quantitatively evaluated the retropharyngeal space (RS) after ACDF and investigated its association with postoperative dysphagia.

METHODS: This multicenter retrospective study analyzed the clinical data of 82 consecutive patients who underwent ACDF. The anteroposterior distance (APD) of the RS was measured at the C2 level using a lateral radiographic view on postoperative day 1. Postoperative dysphagia was subjectively assessed using the Bazaz-Yoo Dysphagia Severity Scale. We statistically evaluated the association between the APD of the RS and postoperative dysphagia.

RESULTS: The mean APD of the RS in all 82 patients was 3.6 mm preoperatively and significantly increased to 8.2 mm postoperatively (P < .0001). Twenty-two patients (26.8%) had postoperative dysphagia. Multivariable analysis revealed that the postoperative APD was associated with postoperative dysphagia (odds ratio 1.27, 95% CI 1.10-1.50, P = .0007). The receiver operating characteristic curve (area under the curve 0.70, 95% CI 0.58-0.83) demonstrated that the postoperative APD of the RS cutoff value was 6.1 mm, with a sensitivity of 100% and a specificity of 35%. With this cutoff value, the positive and negative predictive values for postoperative dysphagia were 36% and 100%, respectively.

CONCLUSION: Our data demonstrate that a value of 6.1 mm for the APD of the RS is an effective indicator for dysphagia after ACDF, which contributes to optimizing the patient management in the acute postoperative period.

Early Voice and Swallowing Disturbance Incidence and Risk Factors After Revision Anterior Cervical Discectomy and Fusion Using a Multidisciplinary Surgical Approach

Neurosurgery 94:444–453, 2024

Dysphagia and vocal cord palsy (VCP) are common otolaryngological complications after revision anterior cervical discectomy and fusion (rACDF) procedures. Our objective was to determine the early incidence and risk factors of VCP and dysphagia after rACDF using a 2-team approach.

METHODS: Single-institution, retrospective analysis of a prospectively collected database of patients undergoing rACDF was enrolled from September 2010 to July 2021. Of 222 patients enrolled, 109 patients were included in the final analysis. All patients had prior ACDF surgery with planned revision using a single otolaryngologist and single neurosurgeon. MD Anderson Dysphagia Inventory and fiberoptic endoscopic evaluation of swallowing (FEES) were used to assess dysphagia. VCP was assessed using videolaryngostroboscopy.

RESULTS: Seven patients (6.7%) developed new postoperative VCP after rACDF. Most cases of VCP resolved by 3 months postoperatively (mean time-to-resolution 79 ± 17.6 days). One patient maintained a permanent deficit. Forty-one patients (37.6%) reached minimum clinically important difference (MCID) in their MD Anderson Dysphagia Inventory composite scores at the 2-week follow-up (MCID decline of ≥6), indicating new clinically relevant swallowing disturbance. Forty-nine patients (45.0%) had functional FEES Performance Score decline. On univariate analysis, there was an association between new VCPs and the number of cervical levels treated at revision (P = .020) with long-segment rACDF (≥4 levels) being an independent risk factor (P = .010). On linear regression, there was an association between the number of levels treated previously and at revision for FEES Performance Score decline (P = .045 and P = .002, respectively). However, on univariate analysis, sex, age, body mass index, operative time, alcohol use, smoking, and individual levels revised were not risk factors for reaching FEES Performance Score decline nor MCID at 2 weeks postoperatively.

CONCLUSION: VCP is more likely to occur in long-segment rACDF but is often temporary. Clinically relevant and functional rates of dysphagia approach 37% and 45%, respectively, at 2 weeks postoperatively after rACDF.

Use of zero-profile device for contiguous three-level anterior cervical discectomy and fusion: comparison with cage and plate construct

J Neurosurg Spine 35:219–226, 2021

The aim of this study was to compare a traditional cervical cage with a zero-profile (ZP) fixation device in patients who underwent three-level anterior cervical decompression and fusion (ACDF) in terms of patient-reported outcomes (visual analog scale [VAS], Japanese Orthopaedic Association [JOA], and Neck Disability Index [NDI] scores), radiographic findings (sagittal alignment 2 years after surgery and likelihood of fusion), and complications.

METHODS This study was a retrospective case series. Between January 2012 and December 2016, 58 patients with cervical spondylotic myelopathy (CSM) who required three-level ACDF procedures, as identified by spinal surgeons, were treated with three-level ACDF and an anterior cage-plate construct (ACPC) (n = 38) or a three-level stand-alone ZP device (n = 20). On the basis of patient choice, patients were divided into two groups (ACPC group and ZP group). All patients completed a minimum of 2 years of follow-up. Patient-reported outcome scores included VAS, JOA, and NDI scores. The radiographic findings included sagittal alignment and likelihood of fusion 2 years after surgery. Data related to patient-reported outcomes and sagittal alignment were collected preoperatively, postoperatively, and at the final follow-up. Intraoperative and postoperative complications were also documented and analyzed.

RESULTS The clinical outcomes, including VAS, JOA, and NDI scores, showed improvement in both groups, and no significant difference was observed between the two groups. Sagittal alignment and height of the fused segments were restored in all patients. However, the authors found no differences between the ZP and ACPC groups, and the groups exhibited similar fusion rates. The authors found no differences in complications, including dysphagia, adjacent-segment degeneration, and postoperative hematoma, between the groups.

CONCLUSIONS Use of ZP implants yielded satisfactory long-term clinical and radiological outcomes that were similar to those of the standard ACPC. Additionally, the rates of complications between the groups were not significantly different. Although the best surgical option for multilevel CSM remains controversial, the results of this work suggest that ACDF with the ZP device is feasible, safe, and effective, even for multilevel CSM.

Perioperative and swallowing outcomes in patients undergoing 4- and 5-level anterior cervical discectomy and fusion

J Neurosurg Spine 34:849–856, 2021

Anterior cervical discectomy and fusion (ACDF) is a common and robust procedure performed on the cervical spine. Literature on ACDF for 4 or more segments is sparse. Increasing the number of operative levels increases surgical complexity, tissue retraction, and risks of complications, particularly dysphagia. The overall risks of these complications and rates of dysphagia are not well studied for surgery on 4 or more segments. In this study, the authors evaluated their institution’s perioperative experience with 4- and 5-level ACDFs.

METHODS The authors retrospectively reviewed patients who underwent 4- or 5-level ACDF at their institution over a 6-year period (May 2013–May 2019). Patient demographics, perioperative complications, readmission rates, and swallowing outcomes were recorded. Outcomes were analyzed with a multivariate linear regression.

RESULTS A total of 174 patients were included (167 had 4-level and 7 had 5-level ACDFs). The average age was 60.6 years, and 54.0% of patients (n = 94) were men. A corpectomy was performed in 12.6% of patients (n = 22). After surgery, 56.9% of patients (n = 99) experienced dysphagia. The percentage of patients with dysphagia decreased to 22.8% (37/162) at 30 days, 12.9% (17/132) at 90 days, and 6.3% (5/79) and 2.8% (1/36) at 1 and 2 years, respectively. Dysphagia was more likely at 90 days postoperatively in patients with gastroesophageal reflux (OR 4.4 [95% CI 1.5–12.8], p = 0.008), and the mean (± SD) lordosis change was greater in patients with dysphagia than those without at 90 days (19.8° ± 13.3° vs 9.1° ± 10.2°, p = 0.003). Dysphagia occurrence did not differ with operative implants, including graft and interbody type. The mean length of time to solid food intake was 2.4 ± 2.1 days. Patients treated with dexamethasone were more likely to achieve solid food intake prior to discharge (OR 4.0 [95% CI 1.5–10.6], p = 0.004). Postsurgery, 5.2% of patients (n = 9) required a feeding tube due to severe approach-related dysphagia. Other perioperative complication rates were uniformly low. Overall, 8.6% of patients (n = 15) returned to the emergency department within 30 days and 2.9% (n = 5) required readmission, whereas 1.1% (n = 2) required unplanned return to surgery within 30 days.

CONCLUSIONS This is the largest series of patients undergoing 4- and 5-level ACDFs reported to date. This procedure was performed safely with minimal intraoperative complications. More than half of the patients experienced in-hospital dysphagia, which increased their overall length of stay, but dysphagia decreased over time.

Effect of Topical Steroid on Swallowing Following ACDF

Spine 2021;46:413–420

Study Design. Randomized, double-blinded, controlled trial.

Objective. To investigate the effectiveness of local intraoperative corticosteroids at decreasing the severity of swallowing difficulty following multilevel anterior cervical discectomy and fusion (ACDF).

Summary of Background Data. Dysphagia is a common complication after ACDF, and while for most patients the symptoms are mild and transient, some patients can suffer from severe dysphagia resulting in significant postoperative morbidity. Previous studies investigating the local application of corticosteroids are limited.

Methods. This was a prospective, randomized, double-blinded, controlled trial of patients undergoing 2, 3, or 4 level ACDF for radiculopathy and/or myelopathy. Patients undergoing multilevel ACDF were randomized to receive local corticosteroid in the retropharyngeal space or placebo (no steroid). Dysphagia was assessed using validated outcomes including the Eating Assessment Tool-10 (Eat-10) and Swallowing Quality of Life (SWALQOL) Questionnaire both preoperatively and at 1 day (POD1), 2 days (POD2), and 1-month postoperatively.

Results. One-hundred nine patients had a complete dataset available for analysis. Eat-10 scores were significantly lower in the Steroid group on POD2 (8 vs. 16, P¼0.03) and 1-month postoperatively (2 vs. 5, P¼0.03). A comparison of the individual SWAL-QOL subscale scores demonstrated that patients in the Steroid group had better scores than the Control group in various subscales at all postoperative time points. Significant differences were noted (always in favor of the Steroid group) in 40% of subscales on POD1, 60% of subscales on POD2, and 50% of subscales at 1-month postoperatively. The Control group never had a better SWAL-QOL subscale score at any time point postoperatively.

Conclusion. Local administration of corticosteroid after multilevel ACDF can decrease postoperative severity and symptomatology of dysphagia during the immediate postoperative period to 1-month postoperatively. The long-term effects of local steroid administration on fusion and other complications will need to be established in future studies.

Level of Evidence: 1

Perioperative complications with multilevel anterior and posterior cervical decompression and fusion

J Neurosurg Spine 32:9–14, 2020

Cervical spondylotic myelopathy (CSM) is a progressive degenerative pathology that frequently affects older individuals and causes spinal cord compression with symptoms of neck pain, radiculopathy, and weakness. Anterior decompression and fusion is the primary intervention to prevent neurological deterioration; however, in severe cases, circumferential decompression and fusion is necessary. Published data regarding perioperative morbidity associated with these complex operations are scarce. In this study, the authors sought to add to this important body of literature by documenting a large single-surgeon experience of single-session circumferential cervical decompression and fusion.

METHODS A retrospective analysis was performed to identify intended single-stage anterior-posterior or posterioranterior- posterior cervical spine decompression and fusion surgeries performed by the primary surgeon (V.C.T.) at Rush University Medical Center between 2009 and 2016. Cases in which true anterior-posterior cervical decompression and fusion was not performed (i.e., those involving anterior-only, posterior-only, or delayed circumferential fusion) were excluded from analysis. Data including standard patient demographic information, comorbidities, previous surgeries, and intraoperative course, along with postoperative outcomes and complications, were collected and analyzed. Perioperative morbidity was recorded during the 90 days following surgery.

RESULTS Seventy-two patients (29 male and 43 female, mean age 57.6 years) were included in the study. Fourteen patients (19.4%) were active smokers, and 56.9% had hypertension, the most common comorbidity. The most common clinical presentation was neck pain in 57 patients (79.2%). Twenty-three patients (31.9%) had myelopathy, and 32 patients (44.4%) had undergone prior cervical spine surgery. Average blood loss was 613 ml. Injury to the vertebral artery was encountered in 1 patient (1.4%). Recurrent laryngeal nerve palsy was observed in 2 patients (2.8%). Two patients (2.8%) had transient unilateral hand grip weakness. There were no permanent neurological deficits. Dysphagia was encountered in 45 patients (62.5%) postoperatively, with 23 (32%) requiring nasogastric parenteral nutrition and 9 (12.5%) patients ultimately undergoing percutaneous endoscopic gastrostomy (PEG) placement. Nine of the 72 patients required a tracheostomy. The incidence of pneumonia was 6.9% (5 patients) overall, and 2 of these patients were in the tracheostomy group. Superficial wound infections occurred in 4 patients (5.6%). Perioperative death occurred in 1 patient. Reoperation was necessary in 10 patients (13.9%). Major perioperative complications (permanent neurological deficit, vascular injury, tracheostomy, PEG tube, stroke, or death) occurred in 30.6% of patients. The risk of minor perioperative complications (temporary deficit, dysphagia, deep vein thrombosis, pulmonary embolism, urinary tract infection, pneumonia, or wound infection) was 80.6%.

CONCLUSIONS Single-session anterior-posterior cervical decompression and fusion is an inherently morbid operation required in select patients with cervical spondylotic myelopathy. In this large single-surgeon series, there was a major perioperative complication risk of 30.6% and minor perioperative complication risk of 80.6%. This overall elevated risk for postoperative complications must be carefully considered and discussed with the patient preoperatively. In some situations, shared decision making may lead to the conclusion that a procedure of lesser magnitude may be more appropriate.

Incidence and Risk Factors for Dysphagia After Anterior Cervical Fusion

ACDF

Spine 2013;38:1820–1825

Study Design. Retrospective database analysis.

Objective. To determine the national incidence, mortality, and risk factors for dysphagia associated with anterior cervical spinal fusion surgery in the United States.

Summary of Background Data. Dysphagia is a known complication associated with anterior cervical fusion (ACF). A population-based database was analyzed to characterize the incidence of dysphagia in terms of demographics, mortality, and risk factors associated with ACF.

Methods. Data from the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project were obtained from 2002 to 2009. Patients undergoing ACF for cervical myelopathy and/ or radiculopathy were identifi ed and separated into cohorts (1- to 2-level and 3 + -level fusions), and incidences of dysphagia were identifi ed. Demographics, length of stay, costs, mortality, and use of bone morphogenetic proteins (BMPs) were assessed. Statistical data were analyzed in SPSS (version 20), using the Student t test for discrete variables and the χ 2 test for categorical data. Binomial logistic regression was used to identify independent predictors of dysphagia. A P value of less than 0.001 was used to denote signifi cance.

Results. A total of 159,590 ACF cases were identified of which 139,434 were 1- to 2-level ACF and 20,156 were 3 + -level ACF. The incidence of dysphagia in the 3 + -level ACF group was double that of the 1- to 2-level ACF group (44.8 vs . 22.4 per 1000; P < 0.001). Patients with dysphagia were significantly older than patients without dysphagia ( P < 0.001). Dysphagia was more common in males undergoing 1- to 2-level ACF ( P < 0.001). BMP was used more frequently for patients with dysphagia in the 1- to 2-level ACF group (9.4% vs . 7.2% of cases; P < 0.001). Logistic regression analysis demonstrated that independent predictors for dysphagia included age ( ≥ 65 yr), male sex, 3 + -level fusion, BMP use, and preoperative patient comorbidities.

Conclusion. Dysphagia occurs twice as often after 3 + -level ACF compared with 1- to 2-level ACF. Utilization of BMP was also linked to an increased incidence of dysphagia in the 1- to 2-level ACF group. Regardless of the number of levels fused, patients experiencing dysphagia had increased age, comorbid risk factors, hospitalizations, and costs.

Level of Evidence: 3

Management of Operative Complications Related to Occipitocervical Instrumentation

Management_of_Operative_Complications_Related_to

Neurosurgery 72[ONS Suppl 2]:ons214–ons228, 2013

The continued evolution of instrumentation techniques for fusions at the craniovertebral junction has enabled surgical treatment of a wide range of developmental, neoplastic, traumatic, and degenerative conditions. There has been an increased recognition of the morbidity associated with the complications secondary to occipitocervical instrumentation.

OBJECTIVE: To present representative complications secondary to occipitocervical instrumentation in patients who presented to our institution and to emphasize underlying principles in diagnosis and management of craniovertebral disease conditions through illustrative examples of their presentation, management, and follow-up.

METHODS: Clinical records for patients referred to the senior author (A.H.M.) between 2005 and 2010 for evaluation and management of their symptoms arising as a consequence of surgical intervention by a different primary neurosurgeon were reviewed.

RESULTS: Eight patients were identified with representative complications secondary to occipitocervical instrumentation. These complications included incorrect surgical technique, persistent instability, hardware misplacement with potential for vascular injury, associated neural injury, and secondary complications of wound healing resulting from methyl methacrylate use. Surgical revision was required in 2 patients. The remaining patients improved with removal of the offending hardware and acrylic cement. All patients reported symptom resolution, and dynamic imaging studies on follow-up indicated stable alignment and bony fusion.

CONCLUSION: These cases serve as illustrative examples of the spectrum of neural, vascular, biomechanical, and instrument-related complications associated with occipitocervical arthrodesis. Basic principles of occipitocervical instrumentation that enable safe and successful treatment of craniovertebral junction disease conditions have been highlighted. Potential complications and management strategies are discussed.

Surgical management of ventral and ventrolateral foramen magnum meningiomas

Neurosurg Rev (2012) 35:359–368

Foramen magnum meningioma poses a challenge for neurosurgeons. Prognosis has generally improved with diagnostic and surgical advances over the past two decades; however, it may ultimately depend more on the surgeon’s ability to tailor the approach and interpret intraoperative risks in single cases.

The series comprised 64 patients operated on for ventral and ventrolateral foramen magnum meningioma. All patients underwent preoperative magnetic resonance imaging and received surgery via the dorsolateral route, rendering the series homogeneous in neuroradiological workup and surgical treatment. Particular to this series was that the majority of patients were of advanced age (n=29; age, >65 years), had serious functional impairment (n=30, Karnofski score <70), and large tumors (mean diameter, 3.5 cm).

Total tumor removal was achieved in 52 (81 %) patients; operative mortality was nil. Early outcome varied depending on difficulties encountered at surgery (cranial nerve position and type of involvement in particular) and type of preoperative dysfunction. Long-tract signs and cerebellar deficits improved in 74 and 77 % of cases, respectively, but only 27 % of cranial nerve deficits did so. Surgical complications most often involved the cranial nerves: cranial nerve impairment, especially of the 9th through the 12th cranial nerves, due to stretching or encasement was noted in 44 cases. At final outcome assessment, two thirds of the cranial nerve deficits cleared, and all but two patients returned to a normal productive life. One patient was reoperated on during the follow-up period.

Foramen magnum meningiomas behave like clival or spinal tumors depending on their prevalent extension. A dorsolateral approach tailored to tumor position and extension and meticulous surgical technique allow for definitive control of surgical complications. Scrupulous postoperative care may prevent dysphagia, a major persistent complication of surgery. Long-term observation of indolent tumor behavior at follow-up suggests that incomplete resection may be a viable surgical treatment option.

Results of a Prospective Randomized Study Comparing a Novel Retractor With a Caspar Retractor in Anterior Cervical Surgery

Neurosurgery 69[ONS Suppl 2]:ons156–ons160, 2011 DOI: 10.1227/NEU.0b013e318219565f

Retraction injury might explain the soft tissue complications seen after anterior cervical surgery. A novel retractor system (Seex retractor system [SRS]) that uses a principle of bone fixation with rotation has been shown to reduce retraction pressure in a cadaveric model of anterior cervical decompression and fusion.

OBJECTIVE: To compare the conventional Cloward-style retractor (CRS) with the SRS in a prospective randomized clinical trial.

METHODS: After ethics and study registration (ACTRN 12608000430336), eligible patients were randomized to either the CRS or SRS before 1- or 2-level anterior cervical decompression and fusion. The pressure beneath the medial retractor blade was recorded with a thin pressure transducer strip. Postoperative sore throat, dysphagia, and dysphonia were assessed after 1, 7, and 28 days.

RESULTS: Twenty-six patients were randomized. There were no serious complications. Complication rates were low with a trend favoring SRS that was not statistically different. Average retraction pressure with SRS was 1.9 mm Hg and with CRS was 5.6 mm Hg (P , .001 on F test; P = .002 on 2-tailed t test). Mean average peak retraction pressure with the SRS was 3.4 mm Hg and with the CRS was 20 mmHg (P , .001 on F test; P = .005 on 2-tailed t test).

CONCLUSION: The new retractor is safe, and statistically similar complication rates were observed with the 2 systems. The SRS generated significantly less retraction pressure compared with the CRS. This difference can be explained by the different principles governing the function of these retractors. Bone fixation gives stability and rotation reduces tissue pressure, both desirable in a retractor.