Long-term Follow-up Results and Radiographic Findings of Anterior Surgery With Cloward Trephination for Cervical Spondylotic Myelopathy

Long-term functional outcome of surgical treatment for degenerative cervical myelopathy

OBJECTIVE

Degenerative cervical myelopathy (DCM) is a major global cause of spinal cord dysfunction. Surgical treatment is considered a safe and effective way to improve functional outcome, although information about long-term functional outcome remains scarce despite increasing longevity. The objective of this study was to describe functional outcome 10 years after surgery for DCM.

METHODS

A prospective observational cohort study was undertaken in a university-affiliated neurosurgery department. All patients who underwent surgery for DCM between 2008 and 2010 as part of the multicenter Cervical Spondylotic Myelopathy International trial were included. Participants were approached for additional virtual assessment 10 years after surgery. Functional outcome was assessed according to the modified Japanese Orthopaedic Association (mJOA; scores 0-18) score at baseline and 1, 2, and 10 years after surgery. The minimal clinically important difference was defined as 1-, 2-, or 3-point improvement for mild, moderate, and severe myelopathy, respectively. Outcome was considered durable when stabilization or improvement after 2 years was maintained at 10 years. Self-evaluated effect of surgery was assessed using a 4-point Likert-like scale. Demographic, clinical, and surgical data were compared between groups that worsened and improved or remained stable using descriptive statistics. Functional outcome was compared between various time points during follow-up with linear mixed models.

RESULTS

Of the 42 originally included patients, 37 participated at follow-up (11.9% loss to follow-up, 100% response rate). The mean patient age was 56.1 years, and 42.9% of patients were female. Surgical approaches were anterior (76.2%), posterior (21.4%), or posterior with fusion (2.4%). The mean follow-up was 10.8 years (range 10-12 years). The mean mJOA score increased significantly from 13.1 (SD 2.3) at baseline to 14.2 (SD 3.3) at 10 years (p = 0.01). A minimal clinically important difference was achieved in 54.1%, and stabilization of functional status was maintained in 75.0% in the long term. Patients who worsened were older (median 63 vs 52 years, p < 0.01) and had more comorbidities (70.0% vs 25.9%, p < 0.01). A beneficial effect of surgery was self-reported by 78.3% of patients.

CONCLUSIONS

Surgical treatment for DCM results in satisfactory improvement of functional outcome that is maintained at 10-year follow-up.

Imaging Evaluation and Relative Significance in Cases of Cervical Disk Allografting: Radiographic Character After Total Disk Transplantation

STUDY DESIGN

The clinical and radiologic data of total disk allografting (TDA) cases were collected and analyzed to explore the correlation between neurological function improvements and imaging changes.

OBJECTIVE

The aim of the study was to assess the medium-term and long-term outcome and radiographic character after TDA, and, furthermore, to explore the significance of the changes of imaging signs after the transplantation.

SUMMARY OF BACKGROUND DATA

Spinal fusion may result in the adjacent segment degeneration. The anxiousness urged the necessity for the development of TDA to reduce the risk of adjacent segment degeneration. Both animal studies and recent clinical trials have shown promising results to support the use of intervertebral disk allograft as a natural mobile disk replacement.

METHODS

The conditions of 13 cases that underwent TDA after cervical discectomy were recorded in detail. Axial symptoms and neurological function in various periods were assessed, and, meanwhile, radiologic examination was performed for the comprehensive evaluation of the relevant indicators before and after surgery.

RESULTS

(1) There was significant improvement in the neurological function after TDA. Postoperatively, the Visual Analog Score of axial symptoms did not increase significantly. (2) Both the entire and local segment maintained a satisfactory curve after allografting. There was no obvious correlation between the neurological function recovery and the cervical curve. Besides, the motion of the cervical spine did not change postoperatively. (3) Postoperatively, the spinal cord area at the index level increased significantly, whereas the signal value of the transplanted disk decreased sharply.

CONCLUSIONS

(1) Disk allografting is one of the effective and safe methods in treating the diseases of cervical disk herniation. (2) Although some degeneration occurs in the transplanted disk, the allograft can still be alive and can successfully maintain and improve the biological characters of the cervical spine in both radiologic and practical aspects.

Post-traumatic lower cervical spine instability: arthrodesis clinical and radiological outcomes at 5 years

BACKGROUND

Anterior cervical fusion is widely used to treat spinal injuries. Radiological evidence of disc abnormalities may develop on either side of the fused segment, raising concern about the potential for inducing adjacent-segment disease. Here, we report the long-term clinical, functional, and radiological outcomes after anterior cervical fusion.

HYPOTHESIS

Anterior cervical fusion influences the development of adjacent-segment disease.

MATERIALS AND METHODS

In a retrospective study, 15 patients aged 17 to 50 years were re-evaluated more than 5 years after anterior spinal fusion to treat post-traumatic cervical-spine instability. We used the Neck Disability Index (NDI) to assess function. Static and dynamic radiographs of the cervical spine were obtained.

RESULTS

NDI values indicated good clinical and functional outcomes, and fusion was achieved consistently. Adjacent-segment disease was a consistent finding at last follow-up but induced no neurological manifestations. Complete fusion of a level adjacent to the treated level was noted in 2 patients. Revision surgery for adjacent-segment disease was not required in any patient.

CONCLUSION

The causative factors of adjacent-segment disease are controversial. Disc degeneration is a normal manifestation of the ageing process. Nevertheless, disc disease is more prevalent at levels adjacent to interbody fusion than in the normal population, suggesting accelerated disc degeneration due to increased loading of the adjacent levels. Furthermore, lesions that are missed during the pre-operative work-up may play a role, as the available investigations do not always have high negative predictive values.

LEVEL OF EVIDENCE

Level IV, retrospective study.

Anterior versus posterior approach for four-level cervical spondylotic myelopathy

The purpose of this study was to compare the results of 2 surgical strategies for 4-level cervical spondylotic myelopathy: a hybrid procedure using anterior cervical diskectomy and fusion (ACDF) combined with segmental corpectomy versus posterior laminectomy and fixation. Between 2002 and 2010, fifty-one patients with consecutive 4-level cervical spondylotic myelopathy were treated surgically, with 27 patients undergoing the hybrid procedure and 24 undergoing posterior laminectomy and fixation. Radiologic data were compared between the 2 groups, including cervical curvature and cervical range of motion (ROM) in the sagittal plane. Pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association (JOA) scoring system and the Nurick grading system. Mean ROM at last follow-up was not significantly different between the 2 groups (P>.05). In the hybrid group, mean JOA score and Nurick grade improved from 9.6±1.4 and 2.74±0.45 respectively, preoperatively, to 13.9±1.3 and 0.86±0.38 respectively, postoperatively. In the fixation group, mean JOA score and Nurick grade improved from 9.4±1.2 and 2.81±0.42 respectively, preoperatively, to 13.1±1.5 and 1.32±0.36 respectively, postoperatively. The JOA scores and Nurick grades at last follow-up were significantly different between the 2 groups (P<.05). In patients with preoperative cervical kyphosis, preoperative JOA score and Nurick grade were not significantly different between the 2 groups (P>.05); however, JOA scores and Nurick grades at last follow-up showed better improvement in the hybrid group than in the fixation group (P<.01). In patients with preoperative cervical lordosis, the preoperative and last follow-up JOA score and Nurick grade were not significantly different between the 2 groups (P>.05).

Anterior surgical options for the treatment of cervical spondylotic myelopathy in a long-term follow-up study

OBJECTIVE

To provide a basis for the choice of anterior surgery procedures in the treatment of cervical spondylotic myelopathy (CSM) through long-term follow-up.

METHODS

A consecutive series of 89 patients with CSM having complete follow-up data were analyzed retrospectively. All patients were treated with anterior cervical discectomy and fusion (ACDF), and anterior cervical corpectomy and fusion (ACCF) from July 2000 to June 2007. The lesions were located in one segment (n = 25), two segments (n = 56), and three segments (n = 8). Preoperative and postoperative, the C2-C7 angle, cervical intervertebral height, radiographic fusion status, result of the adjacent segment degeneration, the Japanese Orthopaedic Association (JOA), and the Short Form 36-item (SF36) questionnaire scores were used to evaluate the efficacy of the surgery.

RESULTS

According to the different compression conditions of the 89 cases, different anterior operation procedures were chosen and satisfactory results were achieved, indicating that direct anterior decompressions were thorough and effective. The follow-up period was 60-108 months, and the average was 79.6 months. The 5-year average symptom improvement rate, effectiveness rate, and fineness rate were 78.36 %, 100 % (89/89), and 86.52 % (77/89), respectively.

CONCLUSIONS

For CSM with compression coming from the front side, proper anterior decompression based on the specific conditions could directly eliminate the compression. Through long-term follow-up, the effect of decompression became observable.

Artificial disk replacement combined with midlevel ACDF versus multilevel fusion for cervical disk disease involving 3 levels

The optimal surgical approach for cervical disk disease remains a matter of debate, especially for multilevel disease. The purpose of this study was to compare the results of 2 surgical strategies for cervical disk disease involving 3 levels: hybrid constructs, artificial disk replacement combined with midlevel anterior cervical diskectomy and fusion (ACDF), and 3-level ACDF. The authors prospectively compared patients who had cervical disk disease involving 3 levels that was treated with hybrid constructs or with 3-level ACDF. Patients were asked to use the Neck Disability Index (NDI) to grade their pain intensity preoperatively and at routine postoperative intervals of 1, 3, 6, 12, and 24 months. Dynamic flexion and extension lateral cervical radiographs were obtained while in the standing position preoperatively and at the postoperative intervals. The angular range of motion for C2-C7 and the adjacent segments was measured using the Cobb method. Twenty-four patients were treated, 12 with hybrid constructs and 12 with 3-level ACDF. Both groups had significant postoperative improvement in NDI scores and neck pain (P<.05). However, no significant difference was found between the groups (P>.05). The hybrid constructs group showed faster recovery of C2-C7 range of motion. Mean C2-C7 range of motion of the hybrid constructs group recovered to that of the preoperative value, but that of the 3-level ACDF group did not (P<.05). Range of motion of the superior and inferior adjacent segments showed significant differences between the 2 groups at 12 and 24 months postoperatively (P<.05). These findings suggest that the hybrid constructs is a safe and effective alternative for cervical disk disease involving 3 levels. The definite stabilization and maintained range of motion can be achieved right away, which can ensure a good preliminary clinical outcome.

Long-term follow-up results of the Cloward procedure for cervical spondylotic myelopathy

PURPOSE

To assess the long-term results of anterior cervical discectomy and fusion using the Cloward procedure for the treatment of cervical spondylotic myelopathy, and to identify possible clinical outcome predictors.

METHODS

A total of 14 cases with a 10-year postoperative follow-up were available (82.4 % of the surviving patients). Patients underwent preoperative and postoperative neurological examination. The symptom severity was graded according to the Nurick scale. MRI measurements were obtained preoperatively. Cervical spine radiographs were obtained preoperatively and at the time of follow-up.

RESULTS

The mean improvement of the clinical status of patients on the Nurick scale was 1.43 ± 0.51 (range 1-2) with respect to the baseline values (p < 0.001), with a 62.5 % recovery rate. A positive association between the improvement of the Nurick scale and the length of follow-up was detected with an age-adjusted univariate analysis (p = 0.042). The Nurick grade improvement was also directly related to preoperative lower limb hyperreflexia (p = 0.039), spasticity (p = 0.017), and bladder dysfunction (p = 0.048). At the time of follow-up, an adjacent discopathy was noted above and below the operated level(s) in eight and six patients, respectively.

CONCLUSIONS

The Cloward technique is a safe and effective procedure for the treatment of cervical spondylotic myelopathy. The patients' preoperative neurological status and the length of follow-up affect the grade of postoperative ambulatory improvement.

Long term results of anterior corpectomy and fusion for cervical spondylotic myelopathy

Background

Results showed good clinical outcomes of anterior corpectomy and fusion (ACCF) for patients with cervical spondylotic myelopathy (CSM) during a short term follow-up; however, studies assessing long term results are relatively scarce. In this study we intended to assess the long term clinical and radiographic outcomes, find out the factors that may affect the long term clinical outcome and evaluate the incidence of adjacent segment disease (ASD).

Methods

This is a retrospective study of 145 consecutive CSM patients on ACCF treatment with a minimum follow-up of 5 years. Clinical data were collected from medical and operative records. Patients were evaluated by using the Japanese Orthopedic Association (JOA) scoring system preoperatively and during the follow-up. X-rays results of cervical spine were obtained from all patients. Correlations between the long term clinical outcome and various factors were also analyzed.

Findings

Ninety-three males and fifty-two females completed the follow-up. The mean age at operation was 51.0 years, and the mean follow-up period was 102.1 months. Both postoperative sagittal segmental alignment (SSA) and the sagittal alignment of the whole cervical spine (SACS) increased significantly in terms of cervical lordosis. The mean increase of JOA was 3.8±1.3 postoperatively, and the overall recovery rate was 62.5%. Logistic regression analysis showed that preoperative duration of symptoms >12 months, high-intensity signal in spinal cord and preoperative JOA score ≤9 were important predictors of the fair recovery rate (≤50%). Repeated surgery due to ASD was performed in 7 (4.8%) cases.

Conclusions

ACCF with anterior plate fixation is a reliable and effective method for treating CSM in terms of JOA score and the recovery rate. The correction of cervical alignment and the repeated surgery rate for ASD are also considered to be satisfactory.

Cervical spondylotic myelopathy: conservative versus surgical treatment after 10 years

It is not known whether the results of decompressive surgery to treat the mild and moderate forms of spondylotic cervical myelopathy (CSM) are any better than those of a conservative approach. A 10-year prospective randomised study was performed. The objective of the study was to compare conservative and operative treatments of mild and moderate, non-progressive, or slowly progressive, forms of CSM. Sixty-four patients were randomised into two groups of 32. Group A was treated conservatively while group B was treated surgically. The clinical outcome was evaluated by modified JOA score, timed 10-m walk, score of daily activities recorded by video and evaluated by two observers blinded to the type of therapy, and by subjective assessment by the patients themselves. Seventeen patents died of natural, unrelated causes, during the follow-up. A total of 25 patients in the conservatively and 22 in the surgically treated group were used for the final evaluation. There was no statistically significant difference between both groups in mJOA score, in subjective evaluation by the patients themselves and in evaluation of video-recordings of daily living activities by two observers blinded to treatment mode. There was neither any difference found in the percentage of patients losing the ability to walk nor in the time taken to cover the 10-m track from a standing start. Comparison of conservative and surgical treatment in mild and moderate forms of CSM in a 10-year follow-up has not shown, on average, a significant difference in results. In both groups, patients get better and worse. According to the power analysis it is necessary admit that these results possess the low ability to answer definitely the question which treatment is better for the patients with a mild and moderate non-progressive CSM because of the low number of patients for the final evaluation and for clinically negligible differences between two compared arms. These findings can serve as a worthy odds-on hypothesis which needs the confirmation.