Retrospective single-centre series of 1300 consecutive cases of outpatient cervical spine surgery: complications, hospital readmissions, and reoperations

Outpatient Spine Procedures in Poland: Clinical Outcomes, Safety, Complications, and Technical Insights into an Ambulatory Spine Surgery Center

PURPOSE

This study evaluated the safety and efficacy of spine procedures performed in an ambulatory spine surgery unit in Poland.

PATIENTS AND METHODS

We conducted a retrospective analysis of 318 patients who underwent ambulatory spine surgery between 2018 and 2021, with procedures including microdiscectomy (MLD), anterior cervical discectomy and fusion (ACDF), endoscopic interbody fusion (endoLIF), posterior endoscopic cervical discectomy (PECD), interlaminar endoscopic lumbar discectomy IELD, and transforaminal endoscopic lumbar discectomy (TELD). Patient data were analyzed for pre-operative and post-operative visual analog scale (VAS) scores.

RESULTS

The findings indicated that outpatient techniques were safe and effective, with a 2.83% complication rate. All procedures significantly improved VAS scores under short-term observation, and core outcome measurement index (COMI) scores under long-term observation.

CONCLUSIONS

Ambulatory spine surgery represents a relatively new approach in Poland, with only a select few centers currently offering this type of service. Outpatient spine surgery is a safe, effective, and cost-effective option for patients requiring basic spine surgeries.

Contralateral Middle Cerebral Artery Territory Infarction After Anterior Cervical Diskectomy and Fusion: A Case Report

CASE

A 70-year-old man underwent anterior cervical diskectomy and fusion (ACDF) of the C3/4 and C4/5 levels by a left-sided approach to address canal stenosis causing right arm weakness. Intraoperative neuromonitoring demonstrated an intermittent decrease in left-sided motor signals. Postoperatively, the patient experienced a right middle cerebral artery stroke. At the 1-year follow-up, right arm strength had improved, but there was persistent left-sided weakness due to stroke.

CONCLUSION

Although rare, possible intraoperative stroke should be considered when there are changes in motor or sensory evoked potentials. In addition, considerations should be given to pursue carotid stenosis screening in patients undergoing ACDF with known atherosclerosis or stroke history.

Anterior surgical treatment for cervical degenerative radiculopathy: a prediction model for non-success

PURPOSE

By using data from the Norwegian Registry for Spine Surgery, we wanted to develop and validate prediction models for non-success in patients operated with anterior surgical techniques for cervical degenerative radiculopathy (CDR).

METHODS

This is a multicentre longitudinal study of 2022 patients undergoing CDR surgery and followed for 12 months to find prognostic models for non-success in neck disability and arm pain using multivariable logistic regression analysis. Model performance was evaluated by area under the receiver operating characteristic curve (AUC) and a calibration test. Internal validation by bootstrapping re-sampling with 1000 repetitions was applied to correct for over-optimism. The clinical usefulness of the neck disability model was explored by developing a risk matrix for individual case examples.

RESULTS

Thirty-eight percent of patients experienced non-success in neck disability and 35% in arm pain. Loss to follow-up was 35% for both groups. Predictors for non-success in neck disability were high physical demands in work, low level of education, pending litigation, previous neck surgery, long duration of arm pain, medium-to-high baseline disability score and presence of anxiety/depression. AUC was 0.78 (95% CI, 0.75, 0.82). For the arm pain model, all predictors for non-success in neck disability, except for anxiety/depression, were found to be significant in addition to foreign mother tongue, smoking and medium-to-high baseline arm pain. AUC was 0.68 (95% CI, 0.64, 0.72).

CONCLUSION

The neck disability model showed high discriminative performance, whereas the arm pain model was shown to be acceptable. Based upon the models, individualized risk estimates can be made and applied in shared decision-making with patients referred for surgical assessment.

Minimally Invasive Posterior Cervical Foraminotomy Versus Anterior Cervical Fusion and Arthroplasty: Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

Patients with lateral cervical disc and foraminal pathology can be treated with anterior and posterior approaches including anterior cervical discectomy and fusion(ACDF), cervical total disc arthroplasty(TDA), and minimally invasive posterior cervical foraminotomy(MIS-PCF). Although MIS-PCF may have some advantages over the anterior approaches, few comparative studies and meta-analyses have been done to assess superiority.

METHODS

This study includes a systematic review of the literature and meta-analysis of studies directly comparing minimally invasive posterior cervical foraminotomy to either anterior cervical discectomy and fusion or cervical total disc arthroplasty.

RESULTS

In comparing patients undergoing ACDF and MIS-PCF, operative time ranged from 68 to 97.8 minutes in the ACDF group compared to 28 to 93.9 minutes in the MIS-PCF group. Mean postoperative length of stay ranged from 33.84 to 112.8 hours in the ACDF group compared to 13.68 to 83.6 hours in the MIS-PCF group. The total complication rates were 3.72% in the ACDF group and 3.73% in the MIS-PCF group. A random-effects model meta-analysis was carried out which failed to show a statistically significant difference in the complication rate between the two procedures(OR .91; 95% CI 0.13, 6.43; P = .92, I² = 59%). The total reoperation rate was 3.5% in the ACDF group and 5.4% in the MIS-PCF group. A random-effects model meta-analysis was carried out which failed to show a statistically significant difference in the reoperation rate between the two procedures(OR .66; 95% CI 0.33, 1.33; P = .25, I² = 0). In comparing patients undergoing TDA and MIS-PCF, operative time ranged from 90.3 to 106.7 minutes in the TDA group compared to 77.4 to 93.9 minutes in the MIS-PCF group. Mean postoperative length of stay ranged from 103.2 to 165.6 hours in the TDA group and 93.6 to 98.4 hours in the MIS-PCF group. The complication rate ranged from 23.5 to 28.6% in the TDA group and 0 to 14.3% in the MIS-PCF group. The overall reoperation rates were 2.6% in the TDA group and 10.2% in the MIS-PCF group.

CONCLUSIONS

There is no clear superiority between MIS-PCF and ACDF/TDA in terms of operative time, postoperative length of stay, or rate of complications/reoperations. Further studies with increased follow-up intervals >48 months, and higher sample sizes are necessary to determine the true superiority of MIS-PCF and anterior neck approaches in treatment of lateral disc and foraminal pathology.

Ambulatory Single-level Posterior Cervical Foraminotomy for Cervical Radiculopathy: A Propensity-matched Analysis of Complication Rates

STUDY DESIGN

Retrospective cohort comparison study.

OBJECTIVE

The aim was to compare perioperative complications and 30-day readmission between ambulatory and inpatient posterior cervical foraminotomy (PCF) in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

SUMMARY OF BACKGROUND DATA

Single-level PCF for cervical radiculopathy is increasingly being performed as an ambulatory procedure. Despite this increase, there is a lack of published literature documenting the safety of ambulatory PCF.

MATERIALS AND METHODS

Patients who underwent PCF (through laminotomy or laminectomy) were identified in the 2005-2018 NSQIP database. Ambulatory procedures were defined as cases that had hospital length of stay=0 days. Inpatient procedures were defined as cases that had length of stay=1-4 days. Patient characteristics, comorbidities, and procedural variables (laminotomy or laminectomy performed) were compared between the 2 cohorts. Propensity score matched comparisons were then performed for postoperative complications and 30-day readmissions between the 2 groups.

RESULTS

In total, 795 ambulatory and 1789 inpatient single-level PCF cases were identified. After matching, there were 795 ambulatory and 795 inpatient cases. Statistical analysis after propensity score matching revealed no significant difference in individual complications including 30-day readmission, thromboembolic events, wound complications, and reoperation, or aggregated complications between ambulatory versus matched inpatient procedures. Overall 30-day readmissions after ambulatory single-level PCF were noted for 2.46% of the study population, and the most common reasons were surgical site infections (46%) and pain control (15%).

CONCLUSIONS

The perioperative outcomes assessed in this study support the conclusion that single-level PCF for cervical radiculopathy can be performed for correctly selected patients in the ambulatory setting without increased rates of 30-day perioperative complications or readmissions compared with inpatient procedures.

LEVEL OF EVIDENCE

Level III.

Routine intraoperative microbiological smear testing in patients with reoperation after elective degenerative non-instrumented spine surgery-useful or negligible adjunct

PURPOSE

Surgical site infections (SSI) are a rare but dreaded cause for recurrent symptomatology requiring reoperation after degenerative spine surgery. We here aim to elucidate if routine microbiological smear testing during reoperation might be a useful tool for subsequent patient management.

METHODS

We investigated clinical, laboratory/imaging characteristics, and outcome of patients undergoing reoperation in the previously affected segment during follow-up after elective degenerative non-instrumented spine surgery. Microbiological cultures via multiple intraoperative smear tests of the superficial/deep wound layers were routinely performed and correlated with clinical/imaging/laboratory/surgical signs for SSI and outcome.

RESULTS

From altogether 2552 patients with degenerative spine surgery in 2014-2019, a total of 62 patients (m:f = 1.6:1, median 69 years) underwent same-level reoperation due to recurrent symptomatology (mean ∆-time:17 ± 36 months) with a predominance of the lumbar spine (90%). In 9 patients with imaging/laboratory suspicious for SSI, microbiological culturing of intraoperative smear testing revealed conclusive pathogen growth in 89% (100% with additional PCR analysis); the predominant pathogen was Staphylococcus aureus with detection mainly in the deep wound layers. In contrast, in 53 patients without clinical/imaging/laboratory/intraoperative signs for SSI microbiological culturing showed minor pathogen growth in 15% displaying bacterial colonization/contamination of the surgical site. The predominant pathogens in this cohort were Staphylococcus epidermidis and Cutibacterium acnes, and these patients had favorable outcomes when monitored with close surveillance without anti-infective treatment.

CONCLUSION

Bacterial colonization/contamination occurs in 15% of patients without signs of infection undergoing same-level reoperation after degenerative spine surgery. These patients can be managed with close surveillance without antibiotic treatment.

A Dynamic Interbody Cage Improves Bone Formation in Anterior Cervical Surgery: A Porcine Biomechanical Study

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) with a rigid interbody spacer is commonly used in the treatment of cervical degenerative disc disease. Although ACDF relieves clinical symptoms, it is associated with several complications such as pseudoarthrosis and adjacent segment degeneration. The concept of dynamic fusion has been proposed to enhance fusion and reduce implant subsidence rate and post-fusion stiffness; this pilot preclinical animal study was conducted to begin to compare rigid and dynamic fusion in ACDF.

QUESTIONS/PURPOSES

Using a pig model, we asked, is there (1) decreased subsidence, (2) reduced axial stiffness in compression, and (3) improved likelihood of bone growth with a dynamic interbody cage compared with a rigid interbody cage in ACDF?

METHODS

ACDF was performed at two levels, C3/4 and C5/6, in 10 pigs weighing 48 to 55 kg at the age of 14 to 18 months (the pigs were skeletally mature). One level was implanted with a conventional rigid interbody cage, and the other level was implanted with a dynamic interbody cage. The conventional rigid interbody cage was implanted in the upper level in the first five pigs and in the lower level in the next five pigs. Both types of interbody cages were implanted with artificial hydroxyapatite and tricalcium phosphate bone grafts. To assess subsidence, we took radiographs at 0, 7, and 14 weeks postoperatively. Subsidence less than 10% of the disc height was considered as no radiologic abnormality. The animals were euthanized at 14 weeks, and each operated-on motion segment was harvested. Five specimens from each group were biomechanically tested under axial compression loading to determine stiffness. The other five specimens from each group were used for microCT evaluation of bone ingrowth and ongrowth and histologic investigation of bone formation. Sample size was determined based on 80% power and an α of 0.05 to detect a between-group difference of successful bone formation of 15%.

RESULTS

With the numbers available, there was no difference in subsidence between the two groups. Seven of 10 operated-on levels with rigid cages had subsidence on a follow-up radiograph at 14 weeks, and subsidence occurred in two of 10 operated-on levels with dynamic cages (Fisher exact test; p = 0.07). The stiffness of the unimplanted rigid interbody cages was higher than the unimplanted dynamic interbody cages. After harvesting, the median (range) stiffness of the motion segments fused with dynamic interbody cages (531 N/mm [372 to 802]) was less than that of motion segments fused with rigid interbody cages (1042 N/mm [905 to 1249]; p = 0.002). Via microCT, we observed bone trabecular formation in both groups. The median (range) proportions of specimens showing bone ongrowth (88% [85% to 92%]) and bone volume fraction (87% [72% to 100%]) were higher in the dynamic interbody cage group than bone ongrowth (79% [71% to 81%]; p < 0.001) and bone volume fraction (66% [51% to 78%]; p < 0.001) in the rigid interbody cage group. The percentage of the cage with bone ingrowth was higher in the dynamic interbody cage group (74% [64% to 90%]) than in the rigid interbody cage group (56% [32% to 63%]; p < 0.001), and the residual bone graft percentage was lower (6% [5% to 8%] versus 13% [10% to 20%]; p < 0.001). In the dynamic interbody cage group, more bone formation was qualitatively observed inside the cages than in the rigid interbody cage group, with a smaller area of fibrotic tissue under histologic investigation.

CONCLUSION

The dynamic interbody cage provided satisfactory stabilization and percentage of bone ongrowth in this in vivo model of ACDF in pigs, with lower stiffness after bone ongrowth and no difference in subsidence.

CLINICAL RELEVANCE

The dynamic interbody cage appears to be worthy of further investigation. An animal study with larger numbers, with longer observation time, with multilevel surgery, and perhaps in the lumbar spine should be considered.

National Rates, Reasons, and Risk Factors for 30- and 90-Day Readmission and Reoperation Among Patients Undergoing Anterior Cervical Discectomy and Fusion: An Analysis Using the Nationwide Readmissions Database

STUDY DESIGN

Retrospective cohort study of the Nationwide Readmissions Database (NRD).

OBJECTIVE

To determine causes of and independent risk factors for 30- and 90-day readmission in a cohort of anterior cervical discectomy and fusion (ACDF) patients.

SUMMARY OF BACKGROUND DATA

Identifying populations at high-risk of 30-day readmission is a priority in healthcare reform so as to reduce cost and patient morbidity. However, among patients undergoing ACDF, nationally-representative data have been limited, and have seldom described 90-day readmissions, early reoperation, or socioeconomic influences.

METHODS

We queried the NRD, which longitudinally tracks 49.3% of hospitalizations, for all adult patients undergoing ACDF. We calculated the rates of, and determined reasons for, readmission and reoperation at 30 and 90 days, and determined risk factors for readmission at each timepoint.

RESULTS

We identified 50,126 patients between January and September 2014. Of these, 2294 (4.6%) and 4152 (8.3%) were readmitted within 30 and 90 days of discharge, respectively, and were most commonly readmitted for infections, medical complications, and dysphagia. The characteristics most strongly associated with readmission were Medicare or Medicaid insurance, length of stay greater than or equal to 4 days, three or more comorbidities, and non-routine discharge, whereas surgical factors (e.g., greater number of vertebrae fused) were more modest. By 30 and 90 days, 8.2% and 11.7% of readmitted patients underwent an additional spinal procedure, respectively.

CONCLUSION

Our analysis uses the NRD to thoroughly characterize readmission in the general ACDF population. Readmissions are often delayed (after 30 days), strongly associated with insurance status, and many result in reoperation. Our results are crucial for risk-stratifying future ACDF patients and developing interventions to reduce readmission.Level of Evidence: 3.

Perspective on morbidity and mortality of cervical surgery performed in outpatient/same day/ambulatory surgicenters versus inpatient facilities

Background:

This is an updated analysis of the morbidity and mortality of cervical surgery performed in outpatient/same day (OSD) (Postoperative care unit [PACU] observation 4–6 h), and ambulatory surgicenters (ASC: PACU 23 h) versus inpatient facilities (IF).

Methods:

We analyzed 19 predominantly level III (retrospective) and IV (case series) studies regarding the morbidity/mortality of cervical surgery performed in OSC/ASC versus IF.

Results:

A “selection bias” clearly favored operating on younger/healthier patients to undergo cervical surgery in OSD/ASC centers resulting in better outcomes. Alternatively, those selected for cervical procedures to be performed in IF classically demonstrated multiple major comorbidities (i.e. advanced age, diabetes, high body mass index, severe myelopathy, smoking, 3–4 level disease, and other comorbidities) and had poorer outcomes. Further, within the typical 4–6 h. PACU “observation window,” OSD facilities “picked up” most major postoperative complications, and typically showed 0% mortality rates. Nevertheless, the author’s review of 2 wrongful death suits (i.e. prior to 2018) arising from OSD ACDF cervical surgery demonstrated that there are probably many more mortalities occurring following discharges from OSD where cervical operations are being performed that are going underreported/unreported.

Conclusion:

“Selection bias” favors choosing younger/healthier patients to undergoing cervical surgery in OSD/ ASC facilities resulting in better outcomes. Atlernatively, choosing older patients with greater comorbidities for IF surgery correlated with poorer results. Although most OSD cervical series report 0% mortality rates, a review of 2 wrongful death suits by just one neurosurgeon prior to 2018 showed there are probably many more mortalities resulting from OSD cervical surgery than have been reported.

Esophagopharyngeal perforation and prevertebral abscess after anterior cervical discectomy and fusion: a case report

Anterior cervical discectomy and fusion (ACDF) represents one of the most commonly performed spine surgeries. Dysphagia secondary to esophageal injury during retraction is one of the most common complications, and usually leads to self-limiting dysphagia. However, actual perforation and violation of the esophageal tissue is much rarer and can lead to delayed deep infections. Prevertebral abscess' are one of the most feared complications after ACDF, as they can lead to severe tissue swelling, osteomyelitis, hardware failure, and even death. Due to their rarity, a gold standard of workup and treatment is still unknown. A healthy 47-year-old female presents 9 months after a C4-C7 ACDF done at an outside institution with a large prevertebral abscess, osteomyelitis, hardware failure, and pseudoarthrosis secondary to esophagopharyngeal defect and prominent hardware. Overall, the patient underwent eight surgeries, and required an extended course of intravenous (IV) antibiotics, multiple diagnostic procedures, and complex soft tissue coverage using an anterolateral thigh free flap. Currently, the patient is doing well 6 months from her last procedure without any complications or plan for future surgery. This was an extremely rare case of a late occurring prevertebral abscess after ACDF. Dysphagia in the late postoperative setting should be evaluated carefully and thoroughly for any esophageal perforation and deep infection. As exemplified in this case, even partial thickness injuries to the esophageal-pharyngeal anatomy due to hardware irrigation can lead to catastrophic complications over time. Safe removal of all hardware anteriorly to avoid continued irritation of the esophagopharyngeal mucosa should be prioritized. If anterior hardware is necessary for stability, implants with the smallest footprint should be utilized. Early collaboration with ENT colleagues should be a priority and can provide crucial diagnostic and therapeutic interventions. Complex closure with a free flap was shown to be an effective way to provide successful definitive soft tissue coverage.

Cost Analysis of Outpatient Anterior Cervical Discectomy and Fusion at an Academic Medical Center without Dedicated Ambulatory Surgery Centers

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) are increasingly performed at ambulatory surgical centers (ASCs). Academic centers lacking dedicated ASCs must perform these at large university hospitals, which pose unique challenges to cost savings and efficiency.

OBJECTIVE

To describe the safety and cost of outpatient ACDF at a major academic medical center without a dedicated ASC.

METHODS

ACDFs performed from 2015 to 2018 were retrospectively reviewed. Cases were performed at the major tertiary university hospital or a satellite university hospital dedicated to outpatient surgery. Patient demographics, surgical characteristics, perioperative complications, fusion at 12 months, and cost were collected.

RESULTS

A total of 470 patients were included. The mean age was 56 years, with 255 women (54.3%). When comparing same-day discharge, overnight observation, or inpatient admission, there were no differences in age, gender, or number of levels fused. Same-day and overnight observation cases were associated with shorter procedure duration and less estimated blood loss. There were no differences in perioperative complications, 30-day readmissions, or fusion at 12 months. Direct and total costs were lowest for same-day cases, followed by overnight observation and inpatient admissions (P < 0.001).

CONCLUSION

Academic centers without dedicated ASCs can safely perform ACDF as a same-day or overnight observation procedure with significant reductions in cost. The lack of a dedicated ASC should not preclude academic centers from allocating appropriately selected patients into same-day or overnight observation care pathways. This strategy can improve resource utilization and preserve precious hospital resources for the most critically ill patients while also allowing these centers to build viable outpatient spine practices.