Radiographic and clinical outcomes following single-level anterior cervical discectomy and allograft fusion without plate placement or cervical collar

A comparison of a self-locking stand-alone cage and anterior cervical plate for ACDF: Minimum 3-year assessment of radiographic and clinical outcomes

OBJECTIVES

The self-locking stand-alone cage has been clinically applied in treating cervical degenerative disc disease (CDDD). However, no long-term clinical and radiographic studies have been performed so far. This retrospective study was designed to analyze and compare the efficacy and outcomes of anterior cervical discectomy and fusion (ACDF) using self-locking stand-alone cages and cages with the anterior cervical plating system.

PATIENTS AND METHODS

A total of 98 consecutive patients were recruited in this study. Patients in the cage group were given stand-alone self-locking cages, and patients in the plate group were treated with cages and anterior plate fixation. The operative time, intraoperative blood loss and complications were recorded. Clinical outcomes were evaluated using the JOA scoring system, Neck Disability Index and Odom's criteria. The cervical lordosis, subsidence and cervical fusion status were assessed by X-ray and computed tomography.

RESULTS

The mean follow-up period was 39.7 months in the cage group and 42.2 months in the plate group. The operative time, intraoperative blood loss, postoperative dysphagia, sore throat and adjacent segment degeneration in the cage group were significantly less than those in the plate group (p < 0.05). All the patients in both groups achieved complete interbody fusion. Postoperative JOA and NDI scores in both groups were obviously improved compared with the preoperative ones. The postoperative cervical lordosis was effectively restored in both groups.

CONCLUSIONS

The self-locking stand-alone cage for ACDF could effectively restore the cervical physiological curvature, cause few complications, and lead to satisfactory outcomes. Therefore, it could be used as an effective and reliable treatment for the CDDD.

Cervicothoracic Lordosis Can Influence Outcome After Posterior Cervical Spine Surgery

Background:

Previous studies on the correlation between cervical sagittal balance with improvement in quality of life showed significant results only for parameters of the anterior translation of the cervical spine (such as C2-C7 SVA).

Objective:

We test whether a new parameter, cervicothoracic lordosis, can predict clinical success in this type of surgery.

Methods:

The focused group involved patients who underwent surgical treatment of cervical degenerative disk disease by the posterior approach, due to myelopathy, radiculopathy or a combination of both. Neurologic deficit was measured before and after surgery with the Nurick Scale, postoperative quality of life, physical and mental components of SF-36 and NDI. Cervicothoracic lordosis and various sagittal balance parameters were also measured. Cervicothoracic lordosis was defined as the angle between: a) the line between the centroid of C2 and the centroid of C7; b) the line between the centroid of C7 and the centroid of T6. Correlations between postoperative quality of life and sagittal parameters were calculated.

Results:

Twenty-nine patients between 27 and 78 years old were evaluated. Surgery types were simple decompression (laminectomy or laminoforaminotomy) (3 patients), laminoplasty (4 patients) and laminectomy with fusion in 22 patients. Significant correlations were found for C2-C7 SVA and cervicothoracic lordosis. C2-C7 SVA correlated negatively with MCS (r=-0.445, p=0.026) and PCS (r=-0.405, p=0.045). Cervicothoracic lordosis correlated positively with MCS (r=0.554, p= 0.004) and PCS (r=0.462, p=0.020) and negatively with NDI (r=-0.416, p=0.031).

Conclusion:

The parameter cervicothoracic lordosis correlates with improvement of quality life after surgery for cervical degenerative disk disease by the posterior approach.

Comparison of Curvature Between the Zero-P Spacer and Traditional Cage and Plate After 3-Level Anterior Cervical Discectomy and Fusion: Mid-term Results

STUDY DESIGN

A retrospective study.

OBJECTIVE

To compare clinical and radiologic outcomes of 3-level anterior cervical discectomy and fusion between a zero-profile (Zero-P) spacer and a traditional plate in cases of symptomatic cervical spine spondylosis.

SUMMARY OF BACKGROUND DATA

Anterior cervical decompression and fusion is indicated for patients with anterior compression or stenosis of the spinal cord. The Zero-P spacers have been used for anterior cervical interbody fusion of 1 or 2 segments. However, there is a paucity of published clinical data regarding the exact impact of the device on cervical curvature of 3-level fixation.

METHODS

Clinical and radiologic data of 71 patients undergoing 3-level anterior cervical discectomy and fusion from January 2010 to January 2012 were collected. Zero-P spacer was implanted in 33 patients, and in 38 cases stabilization was accomplished using an anterior cervical plate and intervertebral cage. Patients were followed for a mean of 30.8 months (range, 24-36 mo) after surgery. Fusion rates, changes in cervical lordosis, and degeneration of adjacent segments were analyzed. Dysphagia was assessed using the Bazaz score, and clinical outcomes were analyzed using the Neck Disability Index and Japanese Orthopedic Association scoring system.

RESULTS

Neurological outcomes did not differ significantly between groups. Significantly less dysphagia was seen at 2- and 6-month follow-up in patients with the Zero-P implant (P<0.05); however, there was significant less cervical lordosis and the lordosis across the fusion in patients with the Zero-P implant (both P<0.05). Degenerative changes in the adjacent segments occurred in 4 patients in the Zero-P group and 6 patients in the standard-plate group (P=0.742); however, no revision surgery was done.

CONCLUSIONS

Clinical results for the Zero-P spacer were satisfactory. The device is superior to the traditional plate in preventing postoperative dysphagia; however, it is inferior at restoring cervical lordosis. It may not provide better sagittal cervical alignment reconstruction in 3-level fixation. Prospective randomized trials with more patients and longer follow-up periods are required to confirm these observations.

Failure Patterns in Standalone Anterior Cervical Discectomy and Fusion Implants

BACKGROUND

Anterior cervical discectomy and fusion is commonly performed using an allograft or autograft implant and anterior screw-supported plate. There has been an increase in the use of standalone cage devices due to ease of use and studies suggesting a lower rate of acute postoperative dysphagia. We review our experience with standalone cage devices and identify risk factors, patterns of failure, and revision surgery approaches.

METHODS

We performed a retrospective case series of patients treated at a single tertiary care institution between March 2014 and March 2015. Inclusion criteria were aged 18-100 years, 1- or 2-level anterior cervical discectomy and fusion with a standalone cervical cage. Data collected included demographics, comorbidities, Charlson comorbidity score, primary diagnosis, and surgical characteristics. Descriptive statistics were performed for risk of readmission, implant failure, revision, and other complications.

RESULTS

We identified 211 patients who met our study criteria. Average surgical time was 107 ± 43 minutes, with an estimated blood loss of 84.6 ± 32.4 mL. There were 11 (5.2%) readmissions. There were 10 (4.74%) implant failures (5 involving single-level surgery and 5 involving 2-level surgery), with 7 cases of pseudoarthrosis. Mechanisms of failure included a C5 body fracture, fusion in a kyphotic alignment after graft subsidence, and acute spondylolisthesis.

CONCLUSIONS

Revision surgery after standalone anterior cervical implants can be complex. Posterior cervical fusion remains a valuable approach to avoid possible vertebral body fracture and loss of fusion area associated with the removal of implants secured through the endplates of adjacent vertebral bodies.

Are External Cervical Orthoses Necessary after Anterior Cervical Discectomy and Fusion: A Review of the Literature

Introduction & Background: The use of external cervical orthosis (ECO) after anterior cervical discectomy and fusion (ACDF) varies from physician to physician due to an absence of clear guidelines. Our purpose is to evaluate and present evidence answering the question, “Does ECO after ACDF improve fusion rates?” through a literature review of current evidence for and against ECO after ACDF. 

Review: A PubMed database search was conducted using specific ECO and ACDF related keywords. Our search yielded a total of 1,267 abstracts and seven relevant articles. In summary, one study provided low quality of evidence results supporting the conclusion that external bracing is not associated with improved fusion rates after ACDF.  The remaining six studies provide very low quality of evidence results; two studies concluded that external bracing after cervical procedures is not associated with improved fusion rates, one study concluded that external bracing after cervical procedures is associated with improved fusion rates, and the remaining three studies lacked sufficient evidence to draw an association between external bracing after ACDF and improved fusion rates.

Conclusion: We recommend against the routine use of ECO after ACDF due to a lack of improved fusion rates associated with external bracing after surgery.

Anterior transcorporeal approach of percutaneous endoscopic cervical discectomy for disc herniation at the C4-C5 levels: a technical note

BACKGROUND CONTEXT

With the continuous development of the spinal endoscopic technique in recent years, percutaneous endoscopic cervical discectomy (PECD) has emerged, which bridges the gap between conservative therapy and traditional surgery and has been mainly divided into the anterior transdiscal approach and the posterior interlaminar access. Because of the relatively greater violation to the anterior nucleus pulposus, there is a higher potential of postoperative intervertebral space decrease in the anterior transdiscal approach than in the posterior interlaminar access. In addition, when the herniated lesion is migrated upward or downward behind the vertebral body, both approaches, and even anterior cervical discectomy and fusion, are impractical, and corpectomy is commonly considered as the only efficacious treatment. Anterior transcorporeal approach under endoscopy could enable an individual and adjustable trajectory within the vertebral body under different conditions of disc herniation preserving the motion of adjacent segment, especially in a migrated or sequestered lesion.

PURPOSE

This report aimed to first describe a novel anterior transcorporeal approach under endoscopy in which we addressed a migrated disc herniation at the C4-C5 levels.

STUDY DESIGN

A technical report was carried out.

PATIENT SAMPLE

A 37-year-old woman presented with posterior neck pain and weakness of extremities for 9 months. On neurologic examination, tingling sensation and numbness were not obvious. However, the power of extremities was dramatically decreased at a level of 3. Hoffmann sign was positive in the bilateral hand. Magnetic resonance imaging (MRI) showed a huge herniation of the C4-C5 disc compressing the median area of the spinal cord. Besides the C4-C5 disc herniation, preoperative computer tomography (CT) also detected that the herniated disc had partial calcification. A novel anterior transcorporeal approach of PECD, through the vertebral body of C5, was performed to address a migrated disc herniation at the C4-C5 levels.

OUTCOME MEASURES

The posterior neck pain was measured using the visual analog scale (VAS).

METHODS

A novel anterior transcorporeal approach under endoscopy was performed to address a migrated disc herniation at the C4-C5 levels.

RESULTS

This operation was accomplished in 75 minutes. Postoperatively, the drainage tube was retained into the drilling hole for 24 hours to avoid the possibility of hematoma. The patient was advised to wear a neck collar for 3 weeks. Immediately after the operation, the posterior neck pain improved from VAS 7/10 preoperatively to 3/10, and the myodynamia of extremities improved stepwise. At 12 hours postoperatively, the range of motion was also improved. In the further follow-up, the patient has completely recovered from the preoperative symptoms, whose myodynamia of extremities is normal. Besides the postoperative MRI, a total removal of the herniated disc and the transcorporeal drilling tunnel are observed in CT. At postoperative 3-month follow-up, neither disc space narrowing nor instability was observed on CT, in which the bone defect after drilling tunnelwas partially decreased, indicating bone healing. There were no surgery-related complications, such as dysphagia, Horner syndrome, recurrent laryngeal nerve palsy, vagus nerve injury, tracheoesophageal injury, or cervical hematocele.

CONCLUSIONS

As a supplement to the described surgical approach of PECD, the transcorporeal approach is a novel access for the treatment of cervical intervertebral disc herniation. Among the advantages of this approach are providing a clear visual field during microendoscopic surgery and decreasing the intraoperative iatrogenic injury to, as well as avoiding violation to the discal tissue. Theoretically, the potential of secondary decline of intervertebral height is low. However, as the limitation of one case shows, whether this transcorporeal approach is efficacious and reliable should be verified in a further comparative cohort study with a large volume of patients.

The Cost Effectiveness of Polyetheretheketone (PEEK) Cages for Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Cost-effectiveness analysis using a Markov model with inputs from published literature.

OBJECTIVE

To learn which graft or hardware option used in a single-level anterior cervical discectomy and fusion (ACDF) is most beneficial in terms of cost, quality of life, and overall cost effectiveness. Options studied were autograft, allograft, and polyetheretherketone (PEEK) cages for cervical fusion.

SUMMARY OF BACKGROUND DATA

ACDF is commonly used to treat cervical myelopathy and/or radiculopathy. No study has compared the cost effectiveness of autograft, allograft, and PEEK in 1-level ACDF.

MATERIALS AND METHODS

A literature review provided inputs into a Markov decision model to determine the most effective graft or hardware option for 1-level ACDF. Data regarding rate of complications, quality-adjusted life years (QALYs) gained, and cost for each procedure type was collected. The Markov model was first run in a base case, using all currently available data. The model was then tested using 1-way and 2-way sensitivity analyses to determine the validity of the model's conclusions if specific aspects of model were changed. This model was run for 10 years postoperatively.

RESULTS

The cost per QALY for each option in the base case analysis was $3328/QALY for PEEK, $2492/QALY for autograft, and $2492/QALY for allograft. All graft/hardware options are cost effective ways to improve outcomes for patients living with chronic neck pain. For graft/hardware options the most cost-effective option was allograft. The incremental cost-effectiveness ratio for PEEK compared with autograft or allograft was >$100,000/QALY.

CONCLUSIONS

Allograft is the most cost-effective graft/hardware option for ACDF. Compared with living with cervical myelopathy and/or radiculopathy, ACDF using any graft or hardware option is a cost-effective method of improving the quality of life of patients. PEEK is not a cost-effective option compared with allograft or autograft for use in ACDF.

Radiological and clinical results of patients after ACDF with and without preoperative software-assisted cage selection

OBJECTIVE

Comparison of software facilitated preoperatively-selected cages versus standard intraoperatively-selected cages, assessing radiological and clinical outcomes of patients after single level cervical discectomy and fusion (ACDF).

METHODS

Cages of study group patients were preoperatively chosen via software-aided dimensioning. Controls obtained cages determined by intraoperative trail implants. Primary endpoints were segmental height (SH), regional angulation (RA) and global cervical angulation (GCA) measured on plain radiographs before, immediately and 12 months after surgery. Neck pain on the visual analogue scale, the neck disability index, and patient satisfaction index recorded at 12 months follow up (FU) were the secondary endpoints.

RESULTS

Each group comprised of 20 patients and both depicted similar demographics and operated segmental levels. Mean postoperative SH was significantly increased in both study and control groups, p<0.001* and p=0.006* respectively. Immediate postoperative gain of lordosis was only significant for the study group p<0.001*. At 12 months FU, SH and RA decreased significantly in both groups. GCA and all secondary endpoints were similar for various measured time points. The two groups did not show any significant difference for all investigated parameters.

CONCLUSION

The radiographical and clinical outcomes of patients receiving cages preoperatively selected by software-assistance are similar to that of patients obtaining conventionally chosen cages. However the former allows for better regional gain/restoration of lordosis.

Reliability assessment of a novel cervical spine deformity classification system

OBJECT

Despite the complexity of cervical spine deformity (CSD) and its significant impact on patient quality of life, there exists no comprehensive classification system. The objective of this study was to develop a novel classification system based on a modified Delphi approach and to characterize the intra- and interobserver reliability of this classification.

METHODS

Based on an extensive literature review and a modified Delphi approach with an expert panel, a CSD classification system was generated. The classification system included a deformity descriptor and 5 modifiers that incorporated sagittal, regional, and global spinopelvic alignment and neurological status. The descriptors included: “C,” “CT,” and “T” for primary cervical kyphotic deformities with an apex in the cervical spine, cervicothoracic junction, or thoracic spine, respectively; “S” for primary coronal deformity with a coronal Cobb angle ≥ 15°; and “CVJ” for primary craniovertebral junction deformity. The modifiers included C2–7 sagittal vertical axis (SVA), horizontal gaze (chin-brow to vertical angle [CBVA]), T1 slope (TS) minus C2–7 lordosis (TS–CL), myelopathy (modified Japanese Orthopaedic Association [mJOA] scale score), and the Scoliosis Research Society (SRS)-Schwab classification for thoracolumbar deformity. Application of the classification system requires the following: 1) full-length standing posteroanterior (PA) and lateral spine radiographs that include the cervical spine and femoral heads; 2) standing PA and lateral cervical spine radiographs; 3) completed and scored mJOA questionnaire; and 4) a clinical photograph or radiograph that includes the skull for measurement of the CBVA. A series of 10 CSD cases, broadly representative of the classification system, were selected and sufficient radiographic and clinical history to enable classification were assembled. A panel of spinal deformity surgeons was queried to classify each case twice, with a minimum of 1 intervening week. Inter- and intrarater reliability measures were based on calculations of Fleiss k coefficient values.

RESULTS

Twenty spinal deformity surgeons participated in this study. Interrater reliability (Fleiss k coefficients) for the deformity descriptor rounds 1 and 2 were 0.489 and 0.280, respectively, and mean intrarater reliability was 0.584. For the modifiers, including the SRS-Schwab components, the interrater (round 1/round 2) and intrarater reliabilities (Fleiss k coefficients) were: C2–7 SVA (0.338/0.412, 0.584), horizontal gaze (0.779/0.430, 0.768), TS-CL (0.721/0.567, 0.720), myelopathy (0.602/0.477, 0.746), SRS-Schwab curve type (0.590/0.433, 0.564), pelvic incidence-lumbar lordosis (0.554/0.386, 0.826), pelvic tilt (0.714/0.627, 0.633), and C7-S1 SVA (0.071/0.064, 0.233), respectively. The parameter with the poorest reliability was the C7–S1 SVA, which may have resulted from differences in interpretation of positive and negative measurements.

CONCLUSIONS

The proposed classification provides a mechanism to assess CSD within the framework of global spinopelvic malalignment and clinically relevant parameters. The intra- and interobserver reliabilities suggest moderate agreement and serve as the basis for subsequent improvement and study of the proposed classification.

A Transtubular Microsurgical Approach to Treat Lateral Cervical Disc Herniation

OBJECTIVE

Different surgical options are available to treat radicular pain syndromes of the cervical spine. Use of the posterior approach for foraminotomy and sequestrectomy (Frykholm) fusion can be avoided, but neck pain affects the postoperative course. This retrospective study compares the classical Frykholm approach and the transtubular microsurgical approach for foraminotomy.

METHODS

From 2004 to 2012, 40 patients fulfilled the inclusion criteria and were enrolled into this retrospective study. The classical Frykholm approach was performed on 25 affected levels. The transtubular microsurgical approach was used on 19 affected levels. Endpoints were neck pain, radicular pain, surgery time, duration of hospital stay, and long-term outcomes.

RESULTS

For the transtubular microsurgical approach and the classical Frykholm approach, the mean surgery time was 77.65 ± 23 minutes and 104 ± 27.59 minutes (P = 0.003), respectively. Radicular pain improved in all patients regardless of the technical approach. Significant differences were observed in neck pain on the first postoperative day (P = 0.003) and at discharge (P = 0.006), resulting in a shorter hospital stay of 4.82 days ± 2.1 for the transtubular microsurgical approach in comparison with 7.43 days ± 3.2 for the Frykholm approach (P = 0.005). According to the criteria of Odom, the rate of an excellent or good outcome was 97.5% (67.5% excellent and 30% good), without any differences between the compared approaches.

CONCLUSION

The transtubular microsurgical approach shows advantages regarding postoperative neck pain, surgery time, and hospital stay with a trend towards an earlier return to work.

Correlation between cervical spine sagittal alignment and clinical outcome after cervical laminoplasty for ossification of the posterior longitudinal ligament

OBJECTIVE

The goal of this study was to determine the relationship between cervical spine sagittal alignment and clinical outcomes after cervical laminoplasty in patients with ossification of the posterior longitudinal ligament (OPLL).

METHODS

Fifty consecutive patients who underwent a cervical laminoplasty for OPLL between January 2012 and January 2013 and who were followed up for at least 1 year were analyzed in this study. Standing plain radiographs of the cervical spine, CT (midsagittal view), and MRI (T2-weighted sagittal view) were obtained (anteroposterior, lateral, flexion, and extension) pre- and postoperatively. Cervical spine alignment was assessed with the following 3 parameters: the C2-7 Cobb angle, C2-7 sagittal vertical axis (SVA), and T-1 slope minus C2-7 Cobb angle. The change in cervical sagittal alignment was defined as the difference between the post- and preoperative C2-7 Cobb angles, C2-7 SVAs, and T-1 slope minus C2-7 Cobb angles. Outcome assessments (visual analog scale [VAS], Oswestry Neck Disability Index [NDI], 36-Item Short-Form Health Survey [SF-36], and Japanese Orthopaedic Association [JOA] scores) were obtained in all patients pre- and postoperatively.

RESULTS

The average patient age was 56.3 years (range 38-72 years). There were 34 male patients and 16 female patients. Cervical laminoplasty for OPLL helped alleviate radiculomyelopathy. Compared with the preoperative scores, improvement was seen in postoperative VAS and JOA scores. After laminoplasty, 35 patients had kyphotic changes, and 15 had lordotic changes. However, cervical sagittal alignment after laminoplasty was not significantly associated with clinical outcomes in terms of postoperative improvement of the JOA score (C2-7 Cobb angle: p = 0.633; C2-7 SVA: p = 0.817; T-1 slope minus C2-7 lordosis: p = 0.554), the SF-36 score (C2-7 Cobb angle: p = 0.554; C2-7 SVA: p = 0.793; T-1 slope minus C2-7 lordosis: p = 0.829), the VAS neck score (C2-7 Cobb angle: p = 0.263; C2-7 SVA: p = 0.716; T-1 slope minus C2-7 lordosis: p = 0.497), or the NDI score (C2-7 Cobb angle: p = 0.568; C2-7 SVA: p = 0.279; T-1 slope minus C2-7 lordosis: p = 0.966). Similarly, the change in cervical sagittal alignment was not related to the JOA (p = 0.604), SF-36 (p = 0.308), VAS neck (p = 0.832), or NDI (p = 0.608) scores.

CONCLUSIONS

Cervical laminoplasty for OPLL improved radiculomyelopathy. Cervical laminoplasty increased the probability of cervical kyphotic alignment. However, cervical sagittal alignment and clinical outcomes were not clearly related.

A meta-analysis of cervical foraminotomy: open versus minimally-invasive techniques

BACKGROUND CONTEXT

The posterior cervical foraminotomy (PCF) may be performed using an open or minimally-invasive (MIS) approach using a tubular retractor. Although there are theoretical advantages such as less blood loss and shorter hospitalizations, there is no consensus in the literature regarding the best approach for treatment.

PURPOSE

To assess clinical outcomes of PCF treated with either an open or an MIS approach using a tubular retractor.

STUDY DESIGN

Systematic literature review and meta-analysis of English language studies for the treatment of cervical radiculopathy treated with foraminotomy.

PATIENT SAMPLE

Pooled patient results from Level I studies and Level IV retrospective studies.

OUTCOME MEASURES

Meta-analysis for clinical success as determined by Odom and Prolo criteria, and visual analog scale scores for arm and neck pain.

METHODS

A literature search of three databases was performed to identify investigations performed in the treatment of PCF with an open or MIS approach. The pooled results were performed by calculating the effect size based on the logit event rate. Studies were weighted by the inverse of the variance, which included both within and between-study errors. Confidence intervals (CIs) were reported at 95%. Heterogeneity was assessed using the Q statistic and I-squared, where I-squared is the estimate of the percentage of error due to between-study variation.

RESULTS

The initial literature search resulted in 195 articles, of which, 20 were determined as relevant on abstract review. An open foraminotomy approach was performed in six; similarly, an MIS approach was performed in three studies. The pooled clinical success rate was 92.7% (CI: 88.9, 95.3) for open foraminotomy and 94.9% (CI: 90.5, 97.4) for MIS foraminotomy, which was not statistically significant (p=.418). The open group demonstrated relative homogeneity with Q value of 7.6 and I(2) value of 34.3%; similarly, the MIS group demonstrated moderate study heterogeneity with Q value of 4.44 and I(2) value of 54.94%.

CONCLUSIONS

Patients with symptomatic cervical radiculopathy from foraminal stenosis can be effectively managed with either a traditional open or an MIS foraminotomy. There is no significant difference in the pooled outcomes between the two groups.

Complications of the anterior approach to the cervical spine

OBJECTIVE: To evaluate the complications of anterior approach to the cervical spine in patients who underwent cervical arthrodesis with instrumentation. METHODS: Prospective and descriptive study was conducted from January 2009 to April 2010. All patients who underwent arthrodesis of the cervical spine by anterior approach were included, regardless the diagnosis. Access was made by the anterior approach on the right side. We evaluated the number of operated levels (1, 2 or 3 levels) and, the type of procedure performed: discectomy and placement of cage and plate (D+C+P), discectomy with placement of a cage (D+C) or corpectomy with placement of cage and plate (C+C+P). All complications related to surgical approach were reported. RESULTS: We studied 34 patients, 70% male. The average age was 50 years and mean follow-up was 8 months. Eighteen percent of patients had complications, distributed as follows: dysphasia (33%) and dysphonic (67%). Among patients who developed complications, most underwent to D+C+P (83%) and no complications were found in patients where no cervical plate was used. Regarding levels, both complications were identified in patients operated to one or two levels. However, in patients operated on three levels, only dysphonia was identified. CONCLUSION: The most frequent complication was dysphonia. Patients who presented more complications were those undergoing discectomy and fusion with cage and anterior cervical plate. All cases of dysphonia were in this group. The number of accessible levels does not seem to have affected the incidence of complications.

Transcorporeal cervical foraminotomy: description of technique and results

OBJECTIVE: Retrospective analyses of 216 patients undergoing foraminal decompression with transcorporeal approach and review of the surgical technique. METHOD: 216 patients with minimum follow-up of 2 years and an average of 41.8 months were included in the study. The clinical records of these patients were reviewed for complications, NDI (neck disability index) and VAS (visual analogue scale). Pre and post-operative radiographs were used to evaluate the disc height. RESULTS: At the end of follow-up patients had significant clinical improvement with reduction of NDI of 88.3% and 86.5% and 68.3% of the VAS for neck and upper limb, respectively (p<0.05). A reduction of 8.8% of the disc height was observed without other complications associated (p<0.05). CONCLUSION: Radicular decompression through a transcorporeal approach is an alternative that provides good clinical results without the need for a fusion and with few complications.

Use of Piezosurgery for removal of retrovertebral body osteophytes in anterior cervical discectomy

BACKGROUND CONTEXT

The relatively new technique of Piezosurgery is based on microvibrations, generated by the piezoelectrical effect, which results in selective bone cutting with preservation of adjacent soft tissue.

PURPOSE

To study the applicability of Piezosurgery in anterior cervical discectomy with fusion (ACDF) surgery.

STUDY DESIGN/SETTING

Prospective clinical study at the neurosurgical department of the University of Freiburg, Germany.

PATIENT SAMPLE

Nine patients with cervical disc herniation and retrovertebral osteophytes who underwent ACDF surgery.

OUTCOME MEASURES

Piezosurgery was evaluated with respect to practicability, safety, preciseness of bone cutting, and preservation of adjacent neurovascular tissue. Pre- and postoperative clinical and radiological data were assessed.

METHODS

Piezosurgery was supportively used in ACDF in nine patients with either radiculopathy or myelopathy from disc herniation or ventral osteophytes. After discectomy, osteophytes were removed with Piezosurgery to decompress the spinal canal and the foramina. Angled inserts were used, allowing for cutting even retrovertebral osteophytes.

RESULTS

In all nine cases, Piezosurgery cut bone selectively with no damage to nerve roots, dura, or posterior longitudinal ligament. None of the patients experienced any new neurological deficit after the operation. The handling of the instrument was safe and the cut precise. Osteophytic spurs, even retrovertebral ones that generally only can be approached via corpectomies, could be safely removed because of the angled inserts through the disc space. Currently, a slightly prolonged operation time was observed for Piezosurgery. Furthermore, the design of the handpiece could be further improved to facilitate the intraoperative handling in ACDF.

CONCLUSIONS

Piezosurgery proved to be a useful and safe technique for selective bone cutting and removal of osteophytes with preservation of neuronal and soft tissue in ACDF. In particular, the angled inserts were effective in cutting bone spurs behind the adjacent vertebra which cannot be reached with conventional rotating burs.

Neurologic recovery after anterior cervical discectomy and fusion

Study Design Retrospective review. Objective The objective of this study is to describe the natural history of neurologic recovery after anterior cervical discectomy and fusion (ACDF). Methods Patients between 18 and 80 years of age, diagnosed with cervical radiculopathy, who underwent single-level ACDF and were followed for a minimum of 2 years were identified from a single-center database. Sensory and motor deficits were documented and graded based on physical examination findings at preoperative and postoperative visits, and used to calculate deficit rates. Results One hundred eighteen patients were included in the study. Mean age was 46 ± 9.2 years and mean follow-up time was 3.8 ± 2.1 years. At the time of surgery, 66% had a sensory deficit. Recovery of sensory function was seen in 85% of patients within 1 year. At final follow-up, new sensory deficits had developed in 30% of patients, 60% of whom had adjacent-level sensory deficits. Patients with preoperative sensory deficits tended to be more likely to develop a new deficit postoperatively (p = 0.05). At the time of surgery, 55% had a motor deficit. Recovery of motor function was seen in 95% of patients within 1 year, and 14% developed new postoperative motor deficits by final follow-up. Of those patients who developed a new motor deficit postoperatively, 76% did so at an adjacent level. Conclusions In our series, a high percentage of patients recovered neurologic function during the first year after ACDF. Adjacent-level and remote-level degeneration were large contributors to neurologic deficits that occurred in subsequent years.

Long-term outcome of the Cloward procedure for single-level cervical degenerative spondylosis. Clinical and radiological assessment after a 22-year mean follow-up

PURPOSE

To evaluate the long-term outcomes of the classical Cloward procedure in single-level cervical spondylosis.

METHODS

A retrospective study of 28 patients who were affected by cervical degenerative spondylosis at C4-C7 segments and treated by the Cloward technique at a single level from 1985-1995 was conducted. The average follow-up period was 22 years (range, 17-27 years). Preoperative clinical complaints were recorded and compared to the current clinical status. Preoperative, 3-6 months postoperative and a current radiographic study were analysed by evaluating the segmental and global sagittal alignment of the cervical spine as well as the occurrence of adjacent disc degeneration.

RESULTS

The most frequently operated segment was C5-C6 (57.1 %), followed by C6-C7 (32.1 %) and C4-C5 (7.1 %). Pain relief and symptom recovery experienced 3-6 months following the surgery was maintained at the most recent follow-up in 85 % of patients. Adjacent disc degeneration was detected in a total of 17 cases (60.7 %). Overall, a group of 14 cases (50 %) had increased lordosis at C2-C7 at the most recent follow-up, with a mean gain of 1.5º Cobb. According to Odom's criteria, 17 patients (60.8 %) presented with excellent clinical outcome, 6 (21.4 %) presented with good outcome, 5 had a (17.8 %) fair outcome, and none had a poor outcome.

CONCLUSIONS

The Cloward technique provided excellent long-term clinical outcome in the treatment of single-level cervical degenerative spondylosis. There were no major alterations of the cervical sagittal balance, and the development of adjacent segment disease (ASD) was not specifically associated with the previous surgery.

Does smoking have an impact on fusion rate in single-level anterior cervical discectomy and fusion with allograft and rigid plate fixation?

Object

Although smoking has been shown to negatively affect fusion rates in patients undergoing multilevel fusions of the cervical and lumbar spine, the effect of smoking on fusion rates in patients undergoing single-level anterior cervical discectomy and fusion (ACDF) with allograft and plate fixation has yet to be thoroughly investigated. The objective of the present study was to address the effect of smoking on fusion rates in patients undergoing a 1-level ACDF with allograft and a locked anterior cervical plate.

Methods

This study is composed of patients from the control groups of 5 separate studies evaluating the use of an anterior cervical disc replacement to treat cervical radiculopathy. For each of the 5 studies the control group consisted of patients who underwent a 1-level ACDF with allograft and a locked cervical plate. The authors of the present study reviewed data obtained in a total of 573 patients; 156 patients were smokers and 417 were nonsmokers. A minimum follow-up period of 24 months was required for inclusion in this study. Fusion status was assessed by independent observers using lateral, neutral, and flexion/extension radiographs.

Results

An overall fusion rate of 91.4% was achieved in all 573 patients. A solid fusion was shown in 382 patients (91.6%) who were nonsmokers. Among patients who were smokers, 142 (91.0%) had radiographic evidence of a solid fusion. A 2-tailed Fisher exact test revealed a p value of 0.867, indicating no difference in the union rates between smokers and nonsmokers.

Conclusions

The authors found no statistically significant difference in fusion status between smokers and nonsmokers who underwent a single-level ACDF with allograft and a locked anterior cervical plate. Although the authors do not promote tobacco use, it appears that the use of allograft with a locked cervical plate in single-level ACDF among smokers produces similar fusion rates as it does in their nonsmoking counterparts.

Cervical radiographical alignment: comprehensive assessment techniques and potential importance in cervical myelopathy

STUDY DESIGN

Narrative review.

OBJECTIVE

To provide a comprehensive narrative review of cervical alignment parameters, the methods for quantifying cervical alignment, normal cervical alignment values, and how alignment is associated with cervical deformity and myelopathy with discussions of health-related quality of life.

SUMMARY OF BACKGROUND DATA

Indications for surgery to correct cervical alignment are not well-defined and there is no set standard to address the amount of correction to be achieved. In addition, classifications of cervical deformity have yet to be fully established and treatment options defined and clarified.

METHODS

A survey of the cervical spine literature was conducted.

RESULTS

New normative cervical alignment values from an asymptomatic volunteer population are introduced, updated methods for quantifying cervical alignment are discussed, and describing the relationship between cervical alignment, disability, and myelopathy are outlined. Specifically, methods used to quantify cervical alignment include cervical lordosis, cervical sagittal vertical axis, and horizontal gaze with the chin-brow vertical angle. Updated methods include T1 slope. Evidence from a few recent studies suggests correlations between radiographical parameters in the cervical spine and health-related quality of life. Analysis of the cervical regional alignment with respect to overall spinal pelvic alignment is emerging and critical. Cervical myelopathy and sagittal alignment of the cervical spine are closely related as cervical deformity can lead to spinal cord compression and tension.

CONCLUSION

Cervical deformity correction should take on a comprehensive approach in assessing global cervical-pelvic relationships and the radiographical parameters that effect health-related quality of life scores are not well-defined. Cervical alignment may be important in assessment and treatment of cervical myelopathy. Future work should concentrate on correlation of cervical alignment parameters to disability scores and myelopathy outcomes. SUMMARY STATEMENTS: STATEMENT 1: Cervical sagittal alignment (cervical SVA and kyphosis) is related to thoracolumbar spinal pelvic alignment and to T1 slope. STATEMENT 2: When significant deformity is clinically or radiographically suspected, regional cervical and relative global spinal alignment should be evaluated preoperatively via standing 3-foot scoliosis X-rays for appropriate operative planning. STATEMENT 3: Cervical sagittal alignment (C2-C7 SVA) is correlated to regional disability, general health scores and to myelopathy severity. STATEMENT 4: When performing decompressive surgery for CSM, consideration should be given to correction of cervical kyphosis and cervical sagittal imbalance (C2-C7 SVA) when present.

Integrated intervertebral device for anterior cervical fusion: An initial experience

Objective:

To analyze the clinical and radiographic results following the use of integrated intervertebral implant in patients with cervical spine degenerative disease.

Background:

Though excellent results have been reported following anterior cervical discectomy and fusion using iliac crest autograft/allograft with plating, the morbidity associated with autograft harvest and small chances of complications with plating always exists. Recently, there has been development of a cervical stand-alone cage with integrated fixation for cervical fusion and stabilization with a possible low morbidity and optimal clinical outcome.

Materials and Methods:

A retrospective study of 16 patients who underwent anterior cervical discectomy and fusion using the integrated intervertebral device was performed. Intra-operative parameters, clinical features [Neck Disability Index (NDI), visual analog scale (VAS) score for neck/arm pain], and presence or absence of dysphagia was recorded. Radiographs were evaluated for assessment of implant failure and fusion.

Results:

Mean age of patients was 54 years (range: 38-84 years) with male: female ratio of 1:3. Follow-up ranged from 6 to 12 months (mean: 10 months). In the early postoperative period, 2 of the 15 patients (13%) patients had mild dysphagia that resolved during follow-up with no patient having complaints of dysphagia at 3-month follow-up. One of the patients with diffuse idiopathic skeletal hyperostosis (DISH) and severe preoperative dysphagia had significant improvement in swallowing function at 3-month follow-up that was stable at 1-year follow-up. There was no evidence of implant failure, with fusion occurring in 95% (19/20) of operated levels. Analysis of follow-up VAS and NDI scores showed significant reduction in VAS score for neck pain (P < 0.019), radicular arm pain (P < 0.003), and NDI score (P < 0.007) in 77, 92, and 77% of patients, respectively, at a mean follow-up of 10 months (6-12 months).

Conclusions:

Our preliminary results with the use of this cervical stand-alone anterior fusion device with integrated screw fixation show its efficacy in anterior cervical decompression and fusion with stabilization with optimal clinical and radiographic outcome. Lower chances of dysphagia with no device-related complications are appealing, which needs to be verified in larger studies.

Autologous iliac bone graft with anterior plating is advantageous over the stand-alone cage for segmental lordosis in single-level cervical disc disease

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) with autologous iliac bone graft and plating has been a standard surgical method for single-level cervical disc disease. The stand-alone cage was introduced to reduce graft-related morbidity. However, problems due to focal kyphosis at the operated level have been on the rise. It has been difficult to derive a conclusive answer from previous studies for the indications of each method.

OBJECTIVE

An interim analysis of a prospective randomized study was performed to compare the sagittal alignment between a stand-alone cage (ACDF cage) and autologous iliac bone graft and plating (ACDF plate).

METHODS

Twenty-nine patients were allocated to the ACDF-cage group (M:F = 17:12) and 23 to the ACDF-plate group (M:F = 14:9). Cobb angles at the operated segment (segmental angle, SA; lordosis vs kyphosis) were compared at postoperative 12 months and the other confounding factors were explored.

RESULTS

Demographic features were not different between groups. The fusion method significantly affected segmental alignment at 12 months (P = .03; odds ratio, 5.52). Preoperatively, the SA was not different between the groups (P = .18) and was similar (P = .22) immediately following the operation. However, the SA was significantly more lordotic (P < .05) in the ACDF-plate group at postoperative 12 months in comparison with the ACDF-cage group. There was no other significant risk factor for segmental kyphosis.

CONCLUSION

The stand-alone cage and autologous bone graft with plating had similar clinical outcomes, but stand-alone cage fusion may be disadvantageous from a radiological viewpoint.

Cervical anterior fusion with the Williams-Isu method: clinical review

Anterior decompression and fusion of the cervical spine is a widely accepted treatment for cervical canal disease. The Williams-Isu method involves cervical anterior fusion with autologous bone grafts from cervical vertebral bodies. Its advantages are a wide operative field, excellent graft fusion, the absence of problems related to the iliac donor site, and direct visualization of the nerve root. For detailed decompression of the cervical root, an ultrasonic bone curette (SONOPET, Stryker Japan K.K., Tokyo) may be useful. To prevent graft extrusion, bioabsorbable screws featuring a head are placed in 4 corners of the bone graft and are fixed with a tap on a part of the graft. The screws are visualized on postoperative X-ray, computed tomography, and magnetic resonance imaging studies. In 69 patients reported elsewhere there were no complications attributable to screw insertion, screw or graft extrusion, or surgery-related infections. When adequate bone cannot be harvested, a piece of ceramic hydroxyapatite is placed between the bone grafts. This sandwich method reinforces the graft, and radiological evidence suggests that it yields better results with respect to the angle and height of the fused segment. For the surgical treatment of cervical ossification of the posterior longitudinal ligament, a large vertebral bone window and a large bone graft are needed; this may result in postoperative radiological worsening. Radiological studies have shown that cervical ossification of the posterior longitudinal ligament can, as can cervical spondylosis, be addressed with the Williams-Isu method. Detailed radiological studies in patients treated with the Williams-Isu method have demonstrated that the range of motion and the disc height of the fused segment must be considered to prevent worsening in that segment after anterior fusion. The Williams-Isu method cannot completely correct cervical alignment, and great caution must be exercised in patients with preoperative malalignment. To reduce the levels to be fused in patients with multilevel lesions due to cervical disease, the Williams-Isu method can be combined with the transvertebral approach. The transvertebral approach facilitated by the wide Williams-Isu window allows the root bifurcation area to be confirmed during the early stage of surgery and possible decompression along the root. Radiological examination has shown that the combination of the Williams-Isu method and transvertebral approach does not affect the fusion level compared with the Williams-Isu method alone and produces better results than does the transvertebral approach alone.

Cervical spine alignment, sagittal deformity, and clinical implications: a review

This paper is a narrative review of normal cervical alignment, methods for quantifying alignment, and how alignment is associated with cervical deformity, myelopathy, and adjacent-segment disease (ASD), with discussions of health-related quality of life (HRQOL). Popular methods currently used to quantify cervical alignment are discussed including cervical lordosis, sagittal vertical axis, and horizontal gaze with the chin-brow to vertical angle. Cervical deformity is examined in detail as deformities localized to the cervical spine affect, and are affected by, other parameters of the spine in preserving global sagittal alignment. An evolving trend is defining cervical sagittal alignment. Evidence from a few recent studies suggests correlations between radiographic parameters in the cervical spine and HRQOL. Analysis of the cervical regional alignment with respect to overall spinal pelvic alignment is critical. The article details mechanisms by which cervical kyphotic deformity potentially leads to ASD and discusses previous studies that suggest how postoperative sagittal malalignment may promote ASD. Further clinical studies are needed to explore the relationship of cervical malalignment and the development of ASD. Sagittal alignment of the cervical spine may play a substantial role in the development of cervical myelopathy as cervical deformity can lead to spinal cord compression and cord tension. Surgical correction of cervical myelopathy should always take into consideration cervical sagittal alignment, as decompression alone may not decrease cord tension induced by kyphosis. Awareness of the development of postlaminectomy kyphosis is critical as it relates to cervical myelopathy. The future direction of cervical deformity correction should include a comprehensive approach in assessing global cervicalpelvic relationships. Just as understanding pelvic incidence as it relates to lumbar lordosis was crucial in building our knowledge of thoracolumbar deformities, T-1 incidence and cervical sagittal balance can further our understanding of cervical deformities. Other important parameters that account for the cervical-pelvic relationship are surveyed in detail, and it is recognized that all such parameters need to be validated in studies that correlate HRQOL outcomes following cervical deformity correction.

Outpatient anterior cervical discectomy and fusion for cervical disk disease: a prospective consecutive series of 96 patients

OBJECTIVES

To evaluate surgical complications and clinical outcome in a consecutive series of 96 patients undergoing anterior cervical discectomy and fusion (ACDF) for cervical disk degeneration (CDD) in an outpatient setting.

METHODS

Pre-, per-, and postoperative data on patients undergoing single- or two-level outpatient ACDF at the private Oslofjord Clinic were prospectively collected.

RESULTS

This study includes 96 consecutive patients with a mean age of 49.1 years. 36/96 had a two-level ACDF. Mean postoperative observation time before discharge was 350 min, and 95/96 were successfully discharged either to their home or to a hotel on the day of surgery. The surgical mortality was 0%, while the surgical morbidity rate was 5.2%. Two (2.1%) patients developed postoperative hematoma, 2 (2.1%) patients experienced postoperative dysphagia, and 1 (1%) experienced deterioration of neurological function. Radicular pain, neck pain, and headache decreased significantly after surgery. 91% of patients were satisfied with the surgery, according to the NASSQ.

CONCLUSION

ACDF in carefully selected patients with CDD appears to be safe in the outpatient setting, provided a sufficient postoperative observation period. The clinical outcome and patient satisfaction of outpatients are comparable to that of inpatients.

[Posterior cervical foraminotomy for the treatment of foraminal conflicts]

Introducción:

La foraminomotima cervical posterior es un procedimiento utilizado para la descompresion radicular por via posterior y constituye una alternativa a la via clásica anterior. En este trabajo evaluamos nuestra serie de pacientes tratados por esta via.

Método:

Desde enero de 2008 a diciembre de 2011, 17 pacientes (18 foraminotomías) fueron operados por presentar cervicobraquialgia a causa de un conflicto foraminal, realizando un foraminotomía cervical posterior. Los pacientes fueron evaluados en el postoperatorio inmediato, al mes y a los 3 meses de la cirugía. Los parámetros para valorar los resultados fueron la Escala Análoga del Dolor (VAS), la Neck Disability Index y los criterios de Odom.

Resultados:

El dolor radicular por conflicto foraminal secundario a hernia de disco cervical fue el síntoma y la patología predominante. El nivel más afectado fue C5-C6. La resolución completa del dolor radicular se observó en casi todos los pacientes. La VAS preoperatoria en promedio fue de 8.8 (mínimo 8 – máximo 10), con una franca mejoría en todos los casos (0.4 en el último control). La media en la Neck Disability Index al inicio fue de 35.3 (mínimo 32 – máximo 45), con una evolución favorable en la evaluación final (0.6). Los Criterios de Odom para la evaluación de pacientes operados de columna cervical fueron satisfactorios con un promedio de 1.17. Se observaron complicaciones en 4 pacientes (23%), todas tuvieron una evolución favorable. No hubo infecciones, discitis ni empeoramiento de los síntomas preexistentes en ningún paciente.

Conclusión:

La foraminotomía cervical posterior es un procedimiento efectivo para el tratamiento del dolor radicular en los conflictos foraminales

Long-term results after cervical anterior fusion using an autologous bone graft (Williams-Isu method)

OBJECTIVE

Cervical anterior fusion with autologous bone grafts (Williams-Isu method) is a modified, accepted method to treat spinal degenerative disease. Here we report minimum 10-year outcomes.

METHODS

Of 101 patients we treated by cervical anterior fusion using the Williams-Isu method, 50 patients were followed up for a mean of 177 months. Among the 51 patients lost to long-term follow-up 12 were contacted by telephone; they reported their condition as good and none required reoperation. We evaluated their clinical outcomes on the Japan Orthopedic Association (JOA) score and assessed radiologic findings.

RESULTS

The average JOA score was 12.5 preoperatively, 15.9 at 2 years after surgery (recovery rate 74.9%), and 15.5 at final follow-up (recovery rate 67.0%). All 5 reoperated patients were treated on the level adjacent to the original lesion. Radiographically, cervical alignment changed from 12.5° to 9.0°, the fused segment angle changed from 5.4° to -0.6°. Although worsening of the fused segment angle did not affect the clinical results, it did affect postoperative cervical sagittal alignment. Cervical alignment and range of motion (ROM) were not different between reoperated (group I) and nonreoperated patients (group II). Fused segment angle worsening was milder than expected in group I.

CONCLUSIONS

The long-term results after the Williams-Isu method were good. The fused segment angle loss of approximately 6° did not affect long-term outcomes although it did affect sagittal cervical alignment. Postoperative worsening of the fused segment angle and hyper ROM changes in the adjacent level were not related to the need for reoperation in our study.

Anterior cervical discectomy and fusion: comparison of titanium and polyetheretherketone cages

BACKGROUND

Titanium (TTN) cages have a higher modulus of elasticity when compared with polyetheretherketone (PEEK) cages. This suggests that TTN-cages could show more frequent cage subsidence after anterior cervical discectomy and fusion (ACDF) and therefore might lead to a higher loss of correction. We compared the long term results of stand-alone PEEK- and TTN-cages in a comparable patient collective that was operated under identical operative settings.

METHODS

From 2002 to 2007 154 patients underwent single-level ACDF for degenerative disc disease (DDD). Clinical and radiological outcome were assessed in 86 eligible patients after a mean of 28.4 months. 44 patients received a TTN- and 42 patients a PEEK-cage.

RESULTS

Solid arthrodesis was found in 93.2% of the TTN-group and 88.1% of the PEEK-group. Cage subsidence was observed in 20.5% of the TTN- and 14.3% of the PEEK-group. A significant segmental lordotic correction was achieved by both cage-types. Even though a loss of correction was found at the last follow-up in both groups, it did not reach the level of statistical significance. Statistical analysis of these results revealed no differences between the TTN- and PEEK-group.When assessed with the neck disability index (NDI), the visual analogue scale (VAS) of neck and arm pain and Odom's criteria the clinical data showed no significant differences between the groups.

CONCLUSIONS

Clinical and radiological outcomes of ACDF with TTN- or PEEK-cages do not appear to be influenced by the chosen synthetic graft. The modulus of elasticity represents only one of many physical properties of a cage. Design, shape, size, surface architecture of a cage as well as bone density, endplate preparation and applied distraction during surgery need to be considered as further important factors.

Comparison of 3 fusion techniques in the treatment of the degenerative cervical spine disease. Is stand-alone autograft really the "gold standard?": prospective study with 2-year follow-up

STUDY DESIGN

A prospective study.

OBJECTIVE

The aim of this study was to compare the 3 different methods of interbody fusion of the cervical spine-autograft in stand-alone technique, autograft with anterior plate, and polyetheretherketone cage supported by anterior plate. The clinical and radiological data obtained were analyzed and discussed.

SUMMARY OF BACKGROUND DATA

Although degenerative cervical spine disease has been treated by an anterior approach for more than 50 years, there is not one generally accepted operative approach. There is a very low-quality evidence of little or no difference in pain relief between each of the techniques. Iliac crest autograft still seems to be the "gold standard" for interbody fusion.

METHODS

Prospective study collecting clinical and radiological data of 81 patients undergoing anterior cervical interbody fusion, in which the interbody fusion of 1 or 2 motion segments from C3 to C7 was done by any of the 3 techniques--stand-alone insertion of autograft (group 1: 28 patients), autograft and anterior plate (group 2: 18 patients), and polyetheretherketone cage filled with beta-tricalcium phosphate and plate (group 3: 29 patients). Patients were followed for 2 years after surgery.

RESULTS

Significant interaction of relative height in the segment and time was found (P < 0.001). The values of the relative height of stand-alone autograft dropped below 95% of initial height and the values of the other 2 groups remained above 105%. Significant interaction of time and group was found for Cobb S angles (P < 0.001). Values of group 1 decreased substantially and remained significantly lower than values of other 2 groups. Fusion rate was 100% in all groups. Neck Disability Index group and time interaction was found (P = 0.023). During postoperative follow-up, group 1 scored in all controls higher than the other 2 groups, but differences were not significant. Visual analogue scale showed effect of time (P < 0.001). This was due to a smaller improvement of patients in group 1 during the whole follow-up in comparison with the other 2 groups. Highest proportion of unsatisfied patients was in group 1 compared with the other 2 groups after 2 years (P = 0.034).

CONCLUSION

Significantly worse radiological and clinical results after 2 years of follow-up were achieved using stand-alone autograft technique in comparison with autograft supported by anterior plating similarly as in comparison with cage implant and anterior plating. Using artificial fusion substrate together with plate and cage can offer the same clinical and radiological results such as iliac autograft and plating. Anterior plating seems to be an important factor influencing the postoperative cervical spine alignment and also the clinical outcome.

Cervical osteophytes causing vocal fold paralysis: case report and literature review

Objectives:

To increase awareness of cervical osteophytes as an extremely rare cause of recurrent laryngeal nerve palsy; to outline the clinical approach to patients with unilateral vocal fold paralysis and to provide an update on the current management of osteoarthritis and osteophytes.

Case report:

An elderly man presented with right unilateral vocal fold immobility and a small phonatory gap. By a diagnosis of exclusion, a cervical osteophyte at the level of the sixth and seventh cervical vertebrae was shown to be the cause. The patient responded to speech therapy and no further intervention was required.

Method:

A literature review, using Medline, identified only one previously published case of vocal fold paralysis due to osteophytes secondary to osteoarthritis.

Conclusion:

The aetiology of unilateral paralysis of the hemilarynx must be fully investigated, as the innervating system has a protracted course, particularly on the left side. Degenerative cervical spine disease, although rare, should be considered as part of the differential diagnosis.

Is external cervical orthotic bracing necessary after posterior atlantoaxial fusion with modern instrumentation: meta-analysis and review of literature

BACKGROUND

No guidelines exist regarding external cervical orthoses (ECO) after atlantoaxial fusion. We reviewed published series describing C1-2 posterior instrumented fusions with screw-rod constructs (SRC) or transarticular screws (TAS) and compared rates of fusion with and without postoperative ECO.

METHODS

Online databases were searched for English-language articles between 1986 and April 2011 describing ECO use after posterior atlantoaxial instrumentation with SRC or TAS. Eighteen studies describing 947 patients who had SRC (± ECO: 254 of 693 patients), and 33 studies describing 1424 patients with TAS (± ECO: 525 of 899 patients) met inclusion criteria. Meta-analysis techniques were applied to estimate rates of fusion with and without ECO use.

RESULTS

All studies provided class III evidence, and no studies directly compared outcomes with or without ECO use. There was no significant difference in the proportion of patients who achieved successful fusion between patients treated with ECO and without ECO for SRC or TAS patients. Point estimates and 95% confidence intervals (CI) for rates of fusion ± ECO were 97.4% (CI: 95.2% to 98.6%) versus 97.9% (CI: 93.6% to 99.3%) for SRC and 93.6% (CI: 90.7% to 95.6%) versus 95.3% (CI: 90.8% to 97.7%) for TAS. There was no correlation between duration of ECO treatment and fusion (dose effect).

CONCLUSIONS

After C1-2 fusion with modern instrumentation, ECO may be unnecessary (class III). Some centers recommend ECO use with patients with softer bone quality (class IV). Prospective, randomized studies with validated radiographic and clinical outcome metrics are necessary to determine the utility of ECO after C1-2 fusion and its impact on patient comfort and cost.

Commentary: Incorporating new technology into spine care: the case of resorbable cervical plates

Commentary on: Lebl DR, Bono CM, Metkar US, et al. Bioabsorbable anterior cervical plate fixation for single-level degenerative disorders: early clinical and radiographic experience. Spine J 2011;11:1002-8 (in this issue).

Bioabsorbable anterior cervical plate fixation for single-level degenerative disorders: early clinical and radiographic experience

BACKGROUND CONTEXT

Increased fusion rates have been reported with the addition of an anterior cervical plate (ACP) to anterior cervical discectomy and fusion (ACDF). Bioabsorbable implants have become increasingly used in orthopedic and spine surgical procedures. There are limited data regarding the outcomes of bioabsorbable ACP (bACP) with ACDF.

PURPOSE

To compare the clinical and radiographic outcomes of patients undergoing ACDF for single-level degenerative disorders with a bACP versus a conventional metal ACP (mACP).

STUDY DESIGN

Retrospective comparative cohort study.

PATIENT SAMPLE

Thirty-one patients undergoing ACDF for a single-level degenerative disorder (ie, disc herniation or spondylotic neural compression).

OUTCOME MEASURES

Incidence of early (within 2 weeks) complications, postoperative sagittal alignment, Odom's criteria, and pseudarthrosis rate.

METHODS

The authors retrospectively reviewed the results of a consecutive series of patients undergoing ACDF for symptomatic single-level disc herniation or spondylotic neural compression with either a bACP or an mACP over a 3-year period. Operative notes, clinical charts, and radiographs were analyzed. Radiographic outcomes were assessed for intersegmental alignment, graft subsidence, fusion rate, prevertebral soft-tissue shadow, and graft containment. Clinical outcome was evaluated by Odom's criteria.

RESULTS

Fourteen patients underwent ACDF with a bACP and 15 with an mACP. Radiographic outcomes at the most recent follow-up demonstrated pseudarthrosis in 4 of 14 patients (29%) in the bACP group and 0 of 15 patients in the mACP group. Graft extrusion and anterior displacement was present in three of four pseudarthroses (75%). Comparing preoperative and final radiographs, cervical lordosis was maintained at the operative segment in only 3 of 14 bACP patients (21%) compared with 8 of 15 patients (53%) in the mACP group. The mean Cobb angle was 2.4°±1.9° lordosis in the mACP group and -2.7°±2.5° kyphosis in the bACP group (p=.12). In the mACP group, 14 of 15 patients had good or excellent results. In the bACP group, only 7 of 14 patients had good or excellent results.

CONCLUSIONS

Bioabsorbable ACP fixation was associated with a high rate of graft extrusion and early loss of intersegmental cervical alignment. Inferior clinical outcomes were observed in patients in the bACP group compared with the mACP group. Based on these findings, continued use of the bACP used in this study cannot be recommended.

Cervical radiculopathy: a review

BACKGROUND

Cervical radiculopathy is defined as a syndrome of pain and/or sensorimotor deficits due to compression of a cervical nerve root. Understanding of this disease is vital for rapid diagnosis and treatment of patients with this condition, facilitating their recovery and return to regular activity.

PURPOSE

This review is designed to clarify (1) the pathophysiology that leads to nerve root compression; (2) the diagnosis of the disease guided by history, physical exam, imaging, and electrophysiology; and (3) operative and non-operative options for treatment and how these should be applied.

METHODS

The PubMed database was searched for relevant articles and these articles were reviewed by independent authors. The conclusions are presented in this manuscript.

RESULTS

Facet joint spondylosis and herniation of the intervertebral disc are the most common causes of nerve root compression. The clinical consequence of radiculopathy is arm pain or paresthesias in the dermatomal distribution of the affected nerve and may or may not be associated with neck pain and motor weakness. Patient history and clinical examination are important for diagnosis. Further imaging modalities, such as x-ray, computed tomography, magnetic resonance imaging, and electrophysiologic testing, are of importance. Most patients will significantly improve from non-surgical active and passive therapies. Indicated for surgery are patients with clinically significant motor deficits, debilitating pain that is resistant to conservative modalities and/or time, or instability in the setting of disabling radiculopathy. Surgical treatment options include anterior cervical decompression with fusion and posterior cervical laminoforaminotomy.

CONCLUSION

Understanding the pathophysiology, diagnosis, treatment indications, and treatment techniques is essential for rapid diagnosis and care of patients with cervical radiculopathy.

Anterior cervical microdiscectomy: is bone grafting and in-situ fusion with instrumentation required?

OBJECTIVE

Anterior cervical microdiscectomy is a procedure commonly performed for degenerative cervical spine disease. However, there is still controversy regarding whether a bone graft with rigid instrument fixation is necessary following single- or two-level discectomy. We review the results of surgery in 120 patients following anterior cervical microdiscectomy without fixation over the last 22 years.

METHODS AND MATERIALS

Anterior cervical microdiscectomy was performed in 120 patients using the Smith-Robinson approach in those with definite MRI evidence of radicular or spinal cord compression by 'soft' or 'hard' disc protrusions. Bone grafting and instrumentation was not done in any of the patients because there was no demonstrable instability of the cervical spine on radiography.

RESULTS

Out of the 100 cases operated by the first author, 95 patients had significant improvement in their symptoms and all returned to their normal employment. Four patients required repeat surgery with bone grafting and instrumentation. Of the 20 cases operated by the second author, 19 patients had significant improvement in their symptoms and returned to normal activities. One patient required repeat surgery for a residual disc causing brachalgia. Thus, only 3.3% of the patients required bone grafting with instrumentation for segmental kyphosis and resultant radiculopathy. The remaining patients were significantly improved, and during the follow-up period over 22 years have not developed recurrences or worsening of symptoms even though bone grafting and instrumentation was not done.

CONCLUSIONS

Anterior cervical microdiscectomy without bone grafting and instrumentation is a safe and effective procedure following single- and two-level discectomy for cervical disc disease, with a success rate of 97.7%. Bone grafting and instrumentation in every case following anterior cervical microdiscectomy is questionable and should only be used in a few selected cases with demonstrated instability.

Prospective, Randomized, Double-Blind Clinical Study Evaluating the Correlation of Clinical Outcomes and Cervical Sagittal Alignment

BACKGROUND:

Sagittal alignment of the cervical spine has received increased attention in the literature as an important determinant of clinical outcomes after anterior cervical diskectomy and fusion. Surgeons use parallel or lordotically fashioned grafts depending on preference or simple availability.

OBJECTIVE:

To quantitatively assess and compare cervical sagittal alignment and clinical outcome when lordotic or parallel allografts were used for fusion.

METHODS:

A prospective, randomized, double-blind clinical study that enrolled 122 patients was performed. The mean follow-up was 37.5 months (range, 12-54 months).

RESULTS:

The mean postoperative cervical sagittal alignment was 19° (range, −7°-36°) and 18° (range, −7°-37°) in the lordotic and parallel graft patient groups, respectively. The mean segmental sagittal alignment was 6° (range, −4°-19°) and 7° (range, −3°-19°) in the lordotic and parallel graft patient groups, respectively. There were no statistically significant differences in clinical outcome scores between the lordotic and parallel graft patient groups. However, patients who had maintained or improved segmental sagittal alignment, regardless of graft type, achieved a higher degree of improvement in Short Form-36 Physical Component Summary and Neck Disability Index scores. This was statistically significant (P &lt; .038).

CONCLUSION:

The use of lordotically shaped allografts does not increase cervical/segmental sagittal alignment or improve clinical outcomes. Maintaining a consistent segmental sagittal alignment or increasing segmental lordosis was related to a higher degree of improvement in clinical outcomes.

Comparison of stand-alone polyetheretherketone cages and iliac crest autografts for the treatment of cervical degenerative disc diseases

BACKGROUND

Anterior cervical decompression and fusion (ACDF) is a widely accepted surgical procedure for the treatment of cervical degenerative disc diseases. This retrospective study was designed to analyze and compare the efficacy and outcomes of anterior cervical fusion using stand-alone polyetheretherketone (PEEK) cages and autogenous iliac crest grafts with the anterior cervical plating system.

METHODS

A total of 72 consecutive patients suffering from cervical degenerative disc diseases treated with ACDF from June 2005 to Dec 2008 were enrolled in the study. Patients in group A (40 patients, 64 segments) had anterior interbody fusion with stand-alone PEEK cages and patients in group B (32 patients, 51 segments) with autogenous iliac crest graft combined with anterior plate fixation. The operative time and intraoperative blood loss were recorded. Clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) scoring system; cervical lordosis, intervertebral height, and cervical fusion status were assessed on X-ray and computed tomography.

FINDINGS

The mean follow-up period was 17.3 months in the stand-alone cage group and 23.2 months in the autologous iliac crest graft group. The operative time and intraoperative blood loss in group A were much less than those in group B (p < 0.05). All the patients in both groups got complete interbody fusion. Postoperative JOA scores in both group A and group B were more than the preoperative ones with significant differences, and the improvement rate of JOA scores had no statistical differences between group A and group B. Postoperative cervical physiological curvature and intervertebral height in both groups were better than the preoperative ones with statistical significances.

CONCLUSIONS

The stand-alone PEEK cage is a good substitute for fusion in patients with cervical disc disease; it can effectively restore the cervical physiological curvature and the intervertebral height, facilitate radiological follow-up, cause few complications, and leads to satisfactory outcomes.

Complications and concerns with osteobiologics for spine fusion in clinical practice

STUDY DESIGN

Literature-based topic review.

OBJECTIVE

To review the complications and the concerns that may be associated with all of the commonly used osteobiologic options for spine fusion.

SUMMARY OF BACKGROUND DATA

Obtaining a solid arthrodesis is an important objective in many lumbar surgical procedures, and a wide array of bone graft materials may be used in an attempt to achieve this goal. Iliac crest bone graft, as well as all of the available osteobiologic alternatives, carries potential risks and concerns for both patient and surgeon.

METHODS

Review of literature and expert opinion.

CONCLUSION

Some of the potential complications associated with osteobiologic materials used in spinal fusion are well understood and clearly documented whereas others require further study and clarification. In any given clinical situation, the patient and surgeon need to balance the benefits and performance characteristics of the graft material with the risk profile to optimize clinical management.

Anterior cervical discectomy with fusion in patients with cervical disc degeneration: a prospective outcome study of 258 patients (181 fused with autologous bone graft and 77 fused with a PEEK cage)

Background

Anterior cervical discectomy with fusion (ACDF) is challenging with respect to both patient selection and choice of surgical procedure. The aim of this study was to evaluate the clinical outcome of ACDF, with respect to both patient selection and choice of surgical procedure: fusion with an autologous iliac crest graft (AICG) versus fusion with an artificial cage made of polyetheretherketone (PEEK).

Methods

This was a non-randomized prospective single-center outcome study of 258 patients who underwent ACDF for cervical disc degeneration (CDD). Fusion was attained with either tricortical AICG or PEEK cages without additional anterior plating, with treatment selected at surgeon's discretion. Radicular pain, neck-pain, headache and patient satisfaction with the treatment were scored using the visual analogue scale (VAS).

Results

The median age was 47.5 (28.3-82.8) years, and 44% of patients were female. 59% had single-level ACDF, 40% had two level ACDF and 1% had three-level ACDF. Of the patients, 181 were fused with AICG and 77 with a PEEK-cage. After surgery, the patients showed a significant reduction in radicular pain (ΔVAS = 3.05), neck pain (ΔVAS = 2.30) and headache (ΔVAS = 0.55). Six months after surgery, 48% of patients had returned to work: however 24% were still receiving workers' compensation.

Using univariate and multivariate analyses we found that high preoperative pain intensity was significantly associated with a decrease in pain intensity after surgery, for all three pain categories. There were no significant correlations between pain relief and the following patient characteristics: fusion method (AICG or PEEK-cage), sex, age, number of levels fused, disc level fused, previous neck surgery (except for neck pain), previous neck trauma, or preoperative symptom duration. Two hundred out of the 256 (78%) patients evaluated the surgical result as successful. Only 27/256 (11%) classified the surgical result as a failure. Patient satisfaction was significantly associated with pain relief after surgery.

Conclusions

ACDF is an effective treatment for radicular pain in selected patients with CDD after six months follow up.

Because of similar clinical outcomes and lack of donor site morbidity when using PEEK, we now prefer fusion with PEEK cage to AICG.

Lengthy symptom duration was not a negative prognostic marker in our patient population.

The number of patients who returned to work 6 months after surgery was lower than expected.

Does the sagittal alignment of the cervical spine have an impact on disk degeneration? Minimum 10-year follow-up of asymptomatic volunteers

There have been few studies that investigated and clarified the relationships between progression of degenerative changes and sagittal alignment of the cervical spine. The objective of the study was to longitudinally evaluate the relationships among progression of degenerative changes of the cervical spine with age, the development of clinical symptoms and sagittal alignment of the cervical spine in healthy subjects. Out of 497 symptom-free volunteers who underwent MRI and plain radiography of the cervical spine between 1994 and 1996, 113 subjects (45 males and 68 females) who responded to our contacts were enrolled. All subjects underwent another MRI at an average of 11.3 years after the initial study. Their mean age at the time of the initial imaging was 36.6 +/- 14.5 years (11-65 years). The items evaluated on MRI were (1) decrease in signal intensity of the intervertebral disks, (2) posterior disk protrusion, and (3) disk space narrowing. Each item was evaluated using a numerical grading system. The subjects were divided into four groups according to the age and sagittal alignment of the cervical spine, i.e., subjects under or over the age of 40 years, and subjects with the lordosis or non-lordosis type of sagittal alignment of the cervical spine. During the 10-year period, progression of decrease in signal intensity of the disk, posterior disk protrusion, and disk space narrowing were recognized in 64.6, 65.5, and 28.3% of the subjects, respectively. Progression of posterior disk protrusion was significantly more frequent in subjects over 40 years of age with non-lordosis type of sagittal alignment. Logistic regression analysis revealed that stiff shoulder was closely correlated with females (P = 0.001), and that numbness of the upper extremity was closely correlated with age (P = 0.030) and male (P = 0.038). However, no significant correlation between the sagittal alignment of the cervical spine and clinical symptoms was detected. Sagittal alignment of the cervical spine had some impact on the progression of degenerative changes of the cervical spine with aging; however, it had no correlation with the occurrence of future clinical symptoms.

Bioabsorbable instrumentation for single-level cervical degenerative disc disease: a radiological and clinical outcome study

Object

The authors present the radiological and clinical outcome data obtained in patients who underwent single-level anterior cervical discectomy and fusion (ACDF) for cervical spondylosis and/or disc herniation; bioabsorbable plates were used for instrumentation. The use of metallic plates in ACDF has gained acceptance as a stabilizing part of the procedure to increase fusion rates, but when complications occur with these devices, the overall effectiveness of the procedure is compromised. As a possible solution, bioabsorbable implants for ACDF have been developed. This study investigates the feasibility and radiological and clinical outcomes of the bioabsorbable plates for ACDF.

Methods

The radiological and clinical outcomes of 30 patients were investigated retrospectively. All patients presented with cervical radiculopathy or myelopathy and underwent single-level ACDF in which a bioabsorbable anterior cervical plate and an allograft bone spacer were placed at a level between C-3 and C-7. Radiological outcome was assessed based on the fusion rate, subsidence, and Cobb angle of the surgical level. Clinical outcome was determined by using a visual analog scale, the Neck Disability Index, and the Odom criteria.

Results

There were no intraoperative complications, and no hardware failure was observed. No signs or symptoms of adverse tissue reaction caused by the implant were seen. Two reoperations were necessary due to postoperative blood collections. The overall complication rate was 16.7%. After 6 months, radiographic fusion was seen in 92.3% of patients. Subsidence at 11.3 ± 7.2 months was 3.1 ± 5.8 mm (an 8.2% change over the immediately postoperative results), and the change in the sagittal curvature was –2.7 ± 2.7°. The visual analog scale score for neck and arm pain and Neck Disability Index improved significantly after surgery (p < 0.001). Overall at 19.5 months postoperatively, 83% of the patients had favorable outcomes based on the Odom criteria.

Conclusions

Absorbable instrumentation provides better stability than the absence of a plate but graft subsidence and deformity rates may be higher than those associated with metal implants. There were no device-related complications, but adverse late effects cannot be excluded. The fusion rate and outcome are comparable to the results achieved with metallic plates. The authors were satisfied with the use of bioabsorbable plates as a reasonable alternative to metal, avoiding the need for lifelong metallic implants.

Anterior cervical discectomy: to graft or not to graft?

The debate regarding whether to perform an interbody fusion after anterior cervical discectomy (ACD) has been going on for the last 50 years. Several prospective randomized clinical trials have been performed to evaluate the clinical outcome following anterior cervical discectomy with and without interbody fusion. None of these studies show a significant difference between the two techniques in terms of relief of arm pain or neck pain. The operative time, in-hospital stay and time for return to work seem to be slightly longer following anterior cervical discectomy with interbody grafting (ACDF) compared to ACD alone. However a temporary increase in postoperative axial pain seems to be a common complication following ACD. There is also no difference in the clinical outcomes between ACD and ACDF with plating and ACDF with interbody spacers. However, if a fusion procedure is undertaken, the use of interbody spacers does have the advantage of avoiding donor site complications. There is also some evidence to suggest that plate fixation can lead to increased fusion rates. There is a significant risk of a degree of segmental kyphosis following ACD. These radiological features, however, do not correlate with the clinical outcome. Radiological and clinical studies fail to show a significant difference in recurrence of foraminal narrowing or the rates of reoperation following ACD or ACDF. The available body of evidence suggests that the addition of a fusion procedure following anterior cervical decompression may give improved radiological results but does not necessarily result in improved clinical outcomes.

Iatrogenic spinal deformity

Patients with postoperative spinal deformities are being identified with increasing frequency as the number of instrumented spinal operations increases. Thus, it is important for the neurosurgeon to understand ways to minimize postoperative deformity and to understand its operative and nonoperative management. A variety of intra- and postoperative risk factors have been associated with postoperative deformity, including patient age, operative positioning, preoperative medical condition, and the use of prior radiation therapy. The evaluation of all patients who have been suspected of iatrogenic deformity should include a detailed physical examination, plain x-rays, and computed tomographic or magnetic resonance imaging, depending on the condition. Conservative therapy includes physical therapy and pain control, which may be effective in some patients. However, patients with flat-back syndrome typically require reoperation. A wide variety of reoperative procedures may be performed, depending on the area of the pathological deformity, extent of disease, and patient condition.

The posterior cervical foraminotomy in the treatment of cervical disc/osteophyte disease: a single-surgeon experience with a minimum of 5 years' clinical and radiographic follow-up

Object

This study details long-term clinical and radiographic outcomes following single-level posterior cervical foraminotomy for degenerative disc or osteophyte disease.

Methods

The authors conducted a retrospective review of 162 cases involving patients treated by a single surgeon using a posterior cervical foraminotomy. Inclusion criteria were a minimum of 5 years' clinical and radiographic follow-up and unilateral single-level posterior cervical foraminotomy for degenerative disease between C-3 and C-7. Patients who had undergone previous operations, those who underwent bilateral procedures, and those who underwent foraminotomy as part of a larger laminectomy were excluded. The Neck Disability Index (NDI) was used for clinical follow-up, and radiographic follow-up was performed using static and dynamic lateral radiographs to compare focal and segmental alignment and changes in disc-space height.

Results

The mean presenting NDI score was 18 (range 2–39). The most common presenting symptoms were radiculopathy (110 patients [68%]), neck pain (85 patients [52%]), and subjective weakness (91 patients [56%]). The mean preoperative focal angulation at the surgically treated level was 4.2° (median 4.1°, range 7.3–15.3°), and the mean preoperative segmental curvature between C-2 and C-7 was 18.0° (median 19.3°, range −22.1 to 39.3°). The mean postoperative NDI score was 8 (range 0–39). Improvement in NDI scores was seen in 150 patients (93%). Resolution of radiculopathy was experienced by 104 patients (95% of patients with radiculopathy). The mean radiographic follow-up was 77.3 months (range 60–177 months). No statistically significant changes in focal or segmental kyphosis or disc-space height were seen among the overall cohort with time (Cox proportional hazards analysis and Student t-test, p > 0.05). The mean postoperative focal angulation was 4.1° (median 3.9°, range −9.9° to 15.1°) and mean postoperative segmental angulation was 17.6° (median 15.4°, range −40.2 to 35.3°). Postoperative instability on dynamic imaging was present in 8 patients (4.9%); 7 of these patients were clinically asymptomatic and were treated conservatively, and 1 required cervical fusion. Postoperative loss of lordosis (defined as segmental Cobb angle < 10°) was seen in 30 patients (20%), 9 of whom had clinical symptoms and 4 of whom required further surgical correction. Factors associated with worsening sagittal alignment (Cox proportional hazards analysis, p < 0.05) included age > 60 at initial surgery, the presence of preoperative cervical lordosis of < 10°, and the need for posterior surgery after the initial foraminotomy

Conclusions

The posterior cervical foraminotomy is highly effective in treating patients with cervical radiculopathy and results in long-lasting pain relief and improved quality-of-life outcomes in most patients. Long-term radiographic follow-up shows no significant trend toward kyphosis, although select patient subsets (patients older than 60 years, patients who had previous posterior surgery, and patients with < 10° of lordosis preoperatively) appear to be at higher risk and require closer follow-up.

Bone graft substitutes in anterior cervical discectomy and fusion

Anterior cervical discectomy with fusion is a common surgical procedure for patients suffering pain and/or neurological deficits and unresponsive to conservative management. For decades, autologous bone grafted from the iliac crest has been used as a substrate for cervical arthrodesis. However patient dissatisfaction with donor site morbidity has led to the search for alternative techniques. We present a literature review examining the progress of available grafting options as assessed in human clinical trials, considering allograft-based, synthetic, factor- and cell-based technologies.