Comparison of radiological outcomes and complications between single-level and multilevel anterior cervical discectomy and fusion (ACDF) by using a polyetheretherketone (PEEK) cage-plate fusion system

Significance of Vertebral Body Sliding Osteotomy as a Surgical Strategy for the Treatment of Cervical Ossification of the Posterior Longitudinal Ligament

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Vertebral body sliding osteotomy (VBSO) has previously been reported as a technique to decompress ossification of the posterior longitudinal ligament (OPLL) by translating the vertebral body anteriorly. This study aimed to evaluate the radiological and clinical efficacies of VBSO and clarify the surgical indications of VBSO for treating myelopathy caused by OPLL.

METHODS

Ninety-seven patients with symptomatic OPLL-induced cervical myelopathy treated with VBSO or laminoplasty who were followed up for more than 2 years were retrospectively reviewed. Cervical alignment, range of motion, fusion, modified K-line (mK-line) status, and minimum interval between ossified mass and mK-line (INT_(min)), and the Japanese Orthopaedic Association (JOA) score were assessed. Patients in the VBSO group were compared with those who underwent laminoplasty.

RESULTS

Cervical lordosis and INT_(min) significantly increased in the VBSO group. All patients in the VBSO group assessed as mK-line (-) preoperatively were assessed as mK-line (+) postoperatively. However, in the LMP group, the mK-line status changed from (+) preoperatively to (-) postoperatively in 3 patients. Final JOA score (p = 0.02) and JOA score improvement (p = 0.01) were significantly higher in the VBSO group. JOA recovery ratio (p = 0.03) and proportion of patients with a recovery rate ≥50% were significantly higher in the VBSO group (p < 0.01).

CONCLUSIONS

VBSO is an effective surgical option for OPLL-induced myelopathy, demonstrating favorable neurological recovery and lordosis restoration with low complication rates. It is best indicated for kyphotic alignment, OPLL with a high space-occupying ratio, and OPLL involving ≤3 segments.

The surgical outcome of multilevel anterior cervical discectomy and fusion in myelopathic elderly and younger patients

The elderly population has an increased risk of degenerative cervical myelopathy due to multilevel disease, causing motor and sensory dysfunctions and a poor quality of life. Multilevel anterior cervical discectomy and fusion (ACDF) is an alternative surgical treatment option, but has a perceived higher risk of complications. The goal of this study is to report the outcome. We retrospectively reviewed patients from 2006 to 2019 undergoing multilevel ACDF for degenerative cervical myelopathy and compared outcomes and complications between elder patients (aged 70 and above) and younger patients (below 70). The patients' comorbidities, and postoperative complications, radiographic parameters such as C2-C7 Cobb angle, C2-C7 sagittal vertical axis, inter-body height of surgical levels and fusion rate were recorded. Japanese Orthopaedic Association (JOA) score and modified Odom's score were collected. Included were 18 elderly (mean age 74, range 70-87) and 45 young patients (mean age 56, range 43-65) with a follow-up of 43.8 and 55.5 months respectively. Three-level ACDF was the most common. The ratios of ASA class III patients were 94.4% and 48.9% (p < 0.001). The Charlson comorbidity indexes were 4.3 ± 1.03 and 2.1 ± 1.11 (p < 0.001). The average lengths of hospital stays were 4.9 and 4.6 days. Eleven patients (61.1%) in the elderly group experienced at least one short-term complication, compared with 16 patients (35.6%) in the younger group (p < 0.05). The middle-term complications were comparable (22.2% and 20.0%). The JOA score, recovery rate and modified Odom score showed comparable result between groups. Despite its extensiveness, multilevel ACDF is feasible for the elder patients with good clinical outcome and fusion rate. When compared to younger cohort, there is a trend of lower preoperative JOA score and recovery rate. The short-term complication rate is higher in the elderly group.

The retropharyngeal steroid use during operation on the fusion rate and dysphagia after ACDF? A systematic review and meta-analysis

PURPOSE

The aim of this meta-analysis was to investigate the effects of retropharyngeal steroid use during operation on bony fusion and dysphagia rate after ACDF.

METHODS

We searched the electronic literature database of PubMed, Embase and the Cochrane Library published from January 1990 to February 2020. The size of each group, mean age, proportion of female patients, dysphagia events and fusion rate at one-year follow-up were extracted. RevMan 5.3 was used for the meta-analysis.

RESULTS

A total of eight studies including six RCTs and two case-control studies met the inclusion criteria. This meta-analysis showed that retropharyngeal steroids could achieve significantly lower dysphagia rates (p < 0.001), higher fusion rates (p = 0.01), less moderate and severe events rates according to the Bazaz stratification (p < 0.001). However, there was no significant difference between two groups regarding operation time (p = 0.67), blood loss (p = 0.33), VAS scores at one day (p = 0.90) and VAS scores at two weeks (p = 0.80).

CONCLUSIONS

Retropharyngeal steroid use is an effective method in reducing dysphagia rate, severe dysphagia rate and increasing fusion rate during ACDF surgery, without increasing operating time, blood loss or VAS scores at one day and two weeks.

LEVEL OF EVIDENCE I

Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Modification of polyetheretherketone implants: From enhancing bone integration to enabling multi-modal therapeutics

Polyetheretherketone (PEEK) is a popular thermoplastic material widely used in engineering applications due to its favorable mechanical properties and stability at high temperatures. With the first implantable grade PEEK being commercialized in 1990s, the use of PEEK has since grown exponentially in the biomedical field and has rapidly transformed a large section of the medical devices landscape. Nowadays, PEEK is a standard biomaterial used across a wide range of implant applications, however, its bioinertness remains a limitation for bone repair applications. The increasing demand for enhanced treatment efficacy/improved patient quality of life, calls for next-generation implants that can offer fast bone integration as well as other desirable therapeutic functions. As such, modification of PEEK implants has progressively shifted from offering desirable mechanical properties, enhancing bioactivity/fast osteointegration, to more recently, tackling post-surgery bacterial infection/biofilm formation, modulation of inflammation and management of bone cancers. Such progress is also accompanied by the evolution of the PEEK manufacturing technologies, to meet the ever increasing demand for more patient specific devices. However, no review has comprehensively covered the recently engaged application areas to date. This paper provides an up-to-date review on the development of PEEK-based biomedical devices in the past 10 years, with particularly focus on modifying PEEK for multi-modal therapeutics. The aim is to provide the peers with a timely update, which may guide and inspire the research and development of next generation PEEK-based healthcare products. STATEMENT OF SIGNIFICANCE: Significant progress has been made in PEEK processing and modification techniques in the past decades, which greatly contributed to its wide applications in the biomedical field. Despite the high volume of published literature on PEEK implant related research, there is a lack of review on its emerging applications in multi-modal therapeutics, which involve bone regeneration, anti-bacteria/anti-inflammation, and cancer inhibition, etc. This timely review covers the state-of-the-art in these exciting areas and provides the important guidance for next generation PEEK based biomedical device research and development.

A Retrospective Evaluation and Review of Outcomes for Single- and Multilevel ACDF With a Zero-Profile Stand-Alone Cage Device With Integrated Instrumentation

This study aimed to assess clinical and radiological outcomes associated with zero-profile stand-alone cages with instrumentation used for single- and multilevel anterior cervical discectomy and fusion (ACDF) operations. Many plate-cage ACDF systems have proven to be successful in producing high fusion rates and positive clinical outcomes. However, the anterior plating in traditional systems has been associated with complications such as dysphagia and mechanical accidents. A total of 190 patients underwent single- or multilevel ACDF surgeries with zero-profile polyetheretherketone cages containing integrated titanium instrumentation and screw fixation (one-level, n=31; two-level, n=65; three-level, n=71; four-level, n=23). Demographic information such as age and smoking status as well as postoperative outcomes were collected and analysed. Out of the 190 patients who underwent ACDF surgeries with a zero-profile stand-alone cage, none experienced any conditions or infections, and zero were readmitted postoperatively. Although traditional plate-cage systems yield high fusion rates in ACDF surgeries, zero-profile systems with integrated fixation have showcased impressive clinical and radiographic results in both single- and multilevel operations.

Neurological deterioration as a result of improper neck position detected by intraoperative neurophysiological monitoring in a cervical stenosis patient: A case report

RATIONALE

Intraoperative neurophysiological monitoring (IONM) is widely used in spinal surgeries to prevent iatrogenic spinal cord injury (SCI). Most surgeons focus on avoiding neurological compromise intraoperatively, while ignoring the possibility of nerve damage preoperatively, such as neck positioning. Thus, this study aims to report a case with transient neurological deterioration due to improper neck position detected by IONM during cervical surgery.

PATIENT CONCERNS

A 63-year-old male patient had been suffering from hypoesthesia of the upper and lower extremities for three years.

DIAGNOSES

Severe cervical stenosis (C5-C7) and cervical ossification of a posterior longitudinal ligament.

INTERVENTIONS

The cervical stenosis patient underwent an anterior cervical corpectomy decompression and fusion (ACDF) surgery with the assistance of IONM. When the lesion segment was exposed, the SSEP and MEP suddenly elicited difficulty indicating that the patient may have developed SCI. All the technical causes of IONM events were eliminated, and the surgeon suspended operation immediately and suspected that the IONM alerts were caused by cervical SCI due to the improper position of the neck. Subsequently, the surgeon repositioned the neck of the patient by using a thinner shoulders pad.

OUTCOMES

At the end of the operation, the MEP and SSEP signals gradually returned to 75% and 80% of the baseline, respectively. Postoperatively, the muscle strength of bilateral biceps decreased from grade IV to grade III. Besides, the sensory disturbance of both upper extremities aggravated. However, the muscle power and hypoesthesia were significantly improved after three months of neurotrophic therapy and rehabilitation training, and no complications of nerve injury were found at the last follow-up visit.

LESSONS

IONM, consisting of SSEP and MEP, should be applied throughout ACDF surgery from the neck positioning to suture incisions. Besides, in the ward 1to 2 days before operation, it is necessary for conscious patients with severe cervical stenosis to simulate the intraoperative neck position. If the conscious patients present signs of nerve damage, they can adjust the neck position immediately until the neurological symptoms relieve. Therefore, intraoperatively, the unconscious patient can be placed in a neck position that was confirmed preoperatively to prevent SCI.

Comparison of Clinical Outcomes and Sagittal Alignment After Different Levels of Anterior Cervical Discectomy and Fusion in Patients With Cervical Spondylotic Myelopathy: From One-level to Three-level

STUDY DESIGN

A nonrandomized and prospective study.

OBJECTIVE

The aim of this study was to compare clinical outcomes and sagittal alignment after one-level, two-level, and three-level anterior cervical discectomy and fusion (ACDF) in patients with cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

ACDF is a widely used surgical approach for CSM. It remains controversial regarding to whether corrected lordosis can be maintained over time after different levels ACDF.

METHODS

A total of 175 patients with cervical spondylotic myelopathy who underwent ACDF were enrolled in this retrospective study. The neurofunctional assessment was performed with the Japanese Orthopedic Association (JOA) score and the recovery rate of JOA score. Radiographic parameters included C2-C7 lordosis, fused segments lordosis, T1 slope, the cervical sagittal vertical axis (cSVA).

RESULTS

Patients with more fusion levels had more operative time and blood loss and higher rate of complications. All patients showed a larger cervical lordosis than that preoperatively and the restored lordosis increased with more segments involved. The restored lordosis had little change during the whole follow-up in one-level and two-level group. CL decreased from 25.65 ± 9.31° on the third postoperative day to 20.25 ± 10.03° at the final follow-up in three-level group (P = 0.001). Only T1 slope in three-level increased significantly from preoperative 26.55 ± 9.36° to 29.06 ± 7.54° on the third postoperative day (P = 0.011) and decreased to 26.89 ± 7.22° (P = 0.043) at final follow-up. The JOA score all increased significantly at the last follow-up in each group, but the recovery rate of the JOA score in each group was similar (P = 0.096).

CONCLUSION

ACDF with different levels had similar postoperative clinical outcomes. Three-level ACDF has an apparent advantage in restoring lordosis, a poor ability to maintain lordosis, and a higher incidence of complications compared to one-level or two-level ACDF.Level of Evidence: 3.

Efficacy and safety of epidural steroid injection following discectomy for patients with lumbar disc herniation: A protocol

BACKGROUND

Concerns exist regarding the analgesia effect and safety of epidural steroid injection (ESI) after discectomy. There is an urgent need of studies that efficiently control for confounding, conduct comprehensive and consecutive observation of potential risks of ESI, and investigate its clinical applicability. We thus further designed a randomized controlled study to assess the efficacy of ESI on postoperative pain and complications in patients undergoing unilateral lumbar microdiscectomy.

METHODS

This prospective, blinded randomized controlled trial was conducted at our single hospital. This study was approved by the Committee at the No.2 People's Hospital of Yibin. All procedures were performed by a single surgeon and informed consent was obtained from each patient. Ninty eligible patients diagnosed at our institution with herniated lumbar disc during a period from June 2020 to July 2021 will be assessed. Group 1 was a mixture of 1 mL of 0.5% bupivacaine and 10 mg of triamcinolone acetonide in 1 mL. Group 2 was a mixture of 1 mL of 0.5% bupivacaine and 1 mL of normal saline. The primary outcome measure was the amount of morphine consumption from a patient-controlled analgesia pump at 12, 24, and 48 hours after surgery. The following secondary outcomes were also assessed: postoperative pain score, back pain score, functional disability, and adverse effect.

CONCLUSIONS

We hypothesized that the ESI was associated with lower pain score, morphine consumption, and hospital stay, with no significant difference in complications for ESI application after lumbar discectomy in lumbar disc herniation when compared with placebo.

TRIAL REGISTRATION

This study protocol was registered in Research Registry (researchregistry5683).

A Review of Complication Rates for Anterior Cervical Diskectomy and Fusion (ACDF)

Background:

There are multiple complications reported for anterior cervical diskectomy and fusion (ACDF), one of the most common cervical spine operations performed in the US (e.g. estimated at 137,000 ACDF/year).

Methods:

Multiple studies analyzed the risks and complications rates attributed to ACDF.

Results:

In multiple studies, overall morbidity rates for ACDF varied from 13.2% to 19.3%. These included in descending order; dysphagia (1.7%-9.5%), postoperative hematoma (0.4%-5.6% (surgery required in 2.4% of 5.6%), with epidural hematoma 0.9%), exacerbation of myelopathy (0.2%-3.3%), symptomatic recurrent laryngeal nerve palsy (0.9%-3.1%), cerebrospinal fluid (CSF) leak (0.5%-1.7%), wound infection (0.1-0.9%-1.6%), increased radiculopathy (1.3%), Horner’s syndrome (0.06%-1.1%), respiratory insufficiency (1.1%), esophageal perforation (0.3%-0.9%, with a mortality rate of 0.1%), and instrument failure (0.1%-0.9%). There were just single case reports of an internal jugular veing occlusion and a phrenic nerve injury. Pseudarthrosis occurred in ACDF and was dependant on the number of levels fused; 0-4.3% (1-level), 24% (2-level), 42% (3 level) to 56% (4 levels). The reoperation rate for symptomatic pseudarthrosis was 11.1%. Readmission rates for ACDF ranged from 5.1% (30 days) to 7.7% (90 days postoperatively).

Conclusions:

Complications attributed to ACDF included; dysphagia, hematoma, worsening myelopathy, recurrent laryngeal nerve palsy, CSF leaks, wound infection, radiculopathy, Horner’s Syndrome, respiratory insufficiency, esophageal perforation, and instrument failure. There were just single case reports of an internal jugular vein thrombosis, and a phrenic nerve injury. As anticipated, pseudarthrosis rates increased with the number of ACDF levels, ranging from 0-4.3% for 1 level up to 56% for 4 level fusions.