Simple model can help predict complication risks after surgery for Cervical Spondylotic Myelopathy
Published on June 27, 2016 ·
A simple model consisting of four risk factors can help surgeons to predict the risk of complications after surgery for cervical spondylotic myelopathy (CSM), reports a study in the July issue of Neurosurgery, official journal of the Congress of Neurological Surgeons, published by Wolters Kluwer.
The presence of other medical conditions, particularly diabetes, is among the factors associated with a higher risk of complications, according to the report by Dr. Michael G. Fehlings of Toronto Western Hospital and colleagues.
Clinical and Surgical Factors Predict Complications after Surgery for CSM
Patients with CSM have neck pain and stiffness, and sometimes numbness and weakness in the arms and legs, caused by pressure on either the spinal cord or major nerve roots. Patients with persistent or severe symptoms may need surgery, which carries a small but definite risk of complications.
Dr. Fehlings and colleagues analyzed data on 479 patients who underwent surgery for CSM as part of an international study. They identified a total of 89 surgery-related complications in 78 patients—a rate of 16.25 percent.
The researchers compared a wide range of clinical and surgical factors for patients with and without surgery. These factors were then incorporated into a "complication prediction rule" to identify those factors associated with an increased risk of complications related to CSM surgery.
Factors related to an increased risk of complications included a condition called "ossification of the posterior longitudinal ligament" (OPLL), where the ligament connecting the bones of the spine becomes calcified, causing compression of the spinal cord. Complications were also more common for patients who had other medical conditions, including diabetes and cardiovascular disease; and for those with a longer duration of surgery or a two-stage operation.
After adjusting for all of these factors together, the final prediction model included four factors. The strongest risk factors were diabetes and the presence of OPLL. The overall number of other medical problems and a longer duration of surgery were also significant predictors of risk.
Caused by several age-related changes, CSM is the most common cause of spinal cord dysfunction in the elderly. Surgery is increasingly recommended because it can halt disease progression and improve patients' function and quality of life.
"Although surgery is generally safe and effective, complications still occur in 11 to 38 percent of patients," Dr. Fehlings and coauthors write. Having a better idea of which patients are at higher risk will help surgeons better anticipate these complications, take preventive steps, and monitor patients during and after surgery.
Based on the new findings, the key risk factors for complications related to CSM surgery are diabetes and other medical problems, OPLL, and a longer duration of surgery. The researchers conclude, "Surgeons can use this information to discuss the risks and benefits of surgery with patients, to plan case-specific preventive strategies, and to ensure appropriate management in the perioperative period."
Wolters Kluwer Health: Lippincott Williams and Wilkins
Clinical and Surgical Predictors of Complications Following Surgery for the Treatment of Cervical Spondylotic Myelopathy: Results From the Multicenter, Prospective AOSpine International Study of 479 Patients
BACKGROUND: Surgery for cervical spondylotic myelopathy (CSM) is generally safe and effective. Nonetheless, complications occur in 11% to 38% of patients. Knowledge of important predictors of complications will help clinicians identify high-risk patients and institute prevention and management strategies.
OBJECTIVE: To identify clinical and surgical predictors of perioperative complications in CSM patients.
METHODS: Four hundred seventy-nine surgical CSM patients were enrolled in the prospective CSM-International study at 16 sites. A panel of physicians reviewed all adverse events and classified each as related or unrelated to surgery. Univariate analyses were performed to determine differences between patients who experienced a perioperative complication and those who did not. A complication prediction rule was developed using multiple logistic regression.
RESULTS: Seventy-eight patients experienced 89 perioperative complications (16.25%). On univariate analysis, the major clinical risk factors were ossification of the posterior longitudinal ligament (OPLL) (P = .055), number of comorbidities (P = .002), comorbidity score (P = .006), diabetes mellitus (P = .001), and coexisting gastrointestinal (P = .039) and cardiovascular (P = .046) disorders. Patients undergoing a 2-stage surgery (P = .002) and those with a longer operative duration (P = .001) were at greater risk of perioperative complications. A final prediction model consisted of diabetes mellitus (odds ratio [OR] = 1.96, P = .060), number of comorbidities (OR = 1.20, P = .069), operative duration (OR = 1.07, P = .002), and OPLL (OR = 1.75, P = .040).
CONCLUSION: Surgical CSM patients have a higher risk of perioperative complications if they have a greater number of comorbidities, coexisting diabetes mellitus, OPLL, and a longer operative duration. Surgeons can use this information to discuss the risks and benefits of surgery with patients, to plan case-specific preventive strategies, and to ensure appropriate management in the perioperative period.
Neurosurgery 79:33–44, 2016 DOI: 10.1227/NEU.0000000000001151
DBM sponges led to 94% fusion rate in posterolateral lumbar spine surgery
Fusion rates with the sponges were comparable to rates with autograft bone.
4 MAY 2016
Compared to autograft bone, which is considered the gold standard graft material for spine fusion, demineralized bone matrix in the form of a sponge was associated with comparable fusion rates and less pain when used for posterolateral lumbar fusion, according to a presenter.
B. Victor Yoon, MS, of Hospital for Special Surgery, in New York City, said demineralized bone matrix (DBM) is readily available, is safe and avoids any second site morbidity with posterolateral lumbar fusion in a presentation based on cases of Andrew A. Sama, MD, of Hospital for Special Surgery.
“Demineralized bone sponge achieves satisfactory fusion without the morbidity related to autograft from iliac crest bone graft harvesting,” Yoon said at the Philadelphia Spine Research Symposium.
The gold standard
Autograft is the gold standard in these cases because there is no risk of disease transmission, it is histocompatible and its properties are ideal for successful healing, Yoon said.
“There are lots of advantages to using your own bone cells and bone graft [because] it is usually coming from your healthy cells, it contains all three of the properties that you need for the graft to be effective. It is osteoconductive, osteoinductive and osteogenic, all at the same time,” he said.
However, there is a limited supply of a patient’s iliac crest autograft bone and the harvest process may be associated with increased pain, morbidity and infection. Surgeons are basically harvesting the material from a patient’s healthy pelvic bone, which leads to damage and a second site of surgery, according to Yoon.
In worst case scenarios, harvesting the iliac crest autograft can actually increase the chances for bone fracture, he said.
DBM sponge found effective
On the other hand, DBM in a sponge form is easy to use and readily available, Yoon said. It is porous, compressible and can effectively absorb fluid like blood or bone marrow. It is effective for use in posterolateral lumbar fusion, interbody fusion procedures, cervical fusion procedures, deformity procedures and other spinal surgical fusion procedures, Yoon said.
Yoon and colleagues studied fusion rates using OsteoSponge (Bacterin) DBM sponge in 122 patients who underwent posterolateral lumbar fusion and they used 2.73 sponges, on average, per patient and available, morcelized local bone from the surgical preparation.The patients’ mean BMI was 30.17.
At final follow-up, four patients experienced nonunion, three patients had a questionable fusion mass and no patients underwent revision surgery.
In all, 115 patients of the 122 patients achieved solid fusion for a 94.26% fusion rate as evaluated by standard radiographic films, which Yoon said is comparable to published fusion rates with autograft.
The patients’ VAS back pain scores decreased from 6.76 preoperatively to 2.85 postoperatively and their VAS leg pain scores decreased from 6.09 preoperatively to 1.95 postoperatively, he noted. –
- Yoon BV. Paper #S2.13. Presented at: Philadelphia Spine Research Symposium; Nov. 9-12, 2015; Philadelphia.
Less invasive approaches for lumbar fusion may be possible for selected patients
May 3, 2016
CHICAGO — Endoscopic fusion under conscious sedation may be an alternative to traditional lumbar spine fusion for select patients, according to data presented at the American Association of Neurological Surgeons Annual Meeting.
“Even less invasive approaches for fusion are possible, leveraging new technology. For selected patients, this is going to work well, but it does not work for everybody. We need to incorporate the other ERAS (Enhanced Recovery After Surgery) components, such as the diet, the psychiatric counseling, medication aspects, etc.,” Michael Y. Wang, MD, FAANS, said.
In a case series study, Wang and colleagues used an endoscopic technique for interbody fusion combined with percutaneous screws without complete general anesthesia. The first 10 consecutive patients were treated using a standard ERAS technique for single-level lumbar fusion under monitored anesthesia care. Minimum follow-up was 1 year, with all patients having clinical and radiographic follow-up of dynamic radiographs and SF-36, EQ-5D and Oswestry Disability Index (ODI) scores taken. All patients had severe disc height collapse, and 60% of patients had a grade 1 spondylolisthesis. Average patient age was 62.2±9 years.
Endoscopic access through Kambin’s triangle allowed for neural decompression, discectomy, endplate preparation and interbody fusion. This was followed by percutaneous pedicle screw and connecting rod placement using liposomal bupivacaine (Exparel, Pacira). The researchers did not use narcotics or regional anesthetics during surgery.
Wang said a successful surgery without conversion to open surgery was achieved for all patients. Mean operative time was 113.5±6.3 minutes and blood loss was 65±38 mL. Hospital length of stay was 1.4±1.3 nights. There were no intraoperative or postoperative complications. The ODI scores improved from a preoperative average of 42 to a final of 13.3. The SF-36 physical component summary and EQ-5D scores also improved.
Wang said there were no cases of nonunion on follow-up imaging and no conversions to general anesthesia or to open surgery were noted. He noted larger clinical series with longer follow-up are needed to validate the clinical improvements and that arthrodesis rates are successful when compared with open surgery.
Wang MY, et al. Paper #601. Presented at: American Association of Neurological Surgeons Annual Meeting. April 30-May 4, 2016; Chicago.
At the American Association of Neurological Surgeons Annual Meeting, Todd H. Lanman, MD, FAANS, spoke about the long-term results of a prospective, randomized, controlled multicenter FDA-approved clinical trial of the Prestige LP Cervical Disc (Medtronic) implanted at two adjacent levels. The low-profile titanium ceramic composite-based artificial cervical disc is indicated for single-level cervical disc disease causing nerve or spinal cord compression from C3 to C7, and is pending FDA premarket approval for two-level use.
Lanman said 7-year data presented here showed patients who had the artificial cervical disc maintained improved clinical outcomes and segmental motion compared to patients who had the standard treatment of two-level anterior cervical discectomy and fusion.
CHICAGO — Gurpreet S. Gandhoke, MD, discussed results of a large database study presented at the American Association of Neurological Surgeons Annual Meeting. In the study, Gandhoke and colleagues looked at the incidence of peripheral nerve injury from positioning during spine surgery. He said the incidence of peripheral nerve injury from positioning among patients was 0.3% and intraoperative monitoring showed high specificity and poor sensitivity in the detection of positioning-related nerve deficits.