Background:
Degenerative cervical myelopathy (DCM) is characterized by neck pain, neck stiffness, weakness, paresthesia, sphincter disturbance and balance disorder. The mean age for symptoms is 64 years and more men than women, 2.7:1, are affected. The most common level is C5-C6. DCM is the predominant cause of spinal cord dysfunction in the elderly worldwide. Surgical options include stand-alone laminectomy, laminectomy and fusion and laminoplasty. The preferable surgical approach is though, a matter of controversy. The objective of this study is to compare stand-alone laminectomy to laminectomy and fusion.
Methods/Design:
This is a multicenter randomized, controlled, parallel group non-inferiority trial. A total of 300 adult participants are allocated in a ratio of 1:1. The primary endpoint is reoperation for any reason within 5 years of follow-up. Sample size and power calculations were performed by estimating the reoperation rate after laminectomy to 3.4% and after laminectomy with fusion to 7.9% based on data from the Swedish spine registry (Swespine) on patients with DCM.
Secondary outcomes are the patient derived modified Japanese orthopaedic association (P-mJOA) score, Neck disability index (NDI), European quality of life five dimensions (EQ-5D), Numeric rating scale (NRS) for neck and arm pain, Hospital anxiety and depression scale (HADS), development of kyphosis measured as the cervical sagittal vertical axis (cSVA) and, death. Clinical and radiological follow-up is performed at 3, 12, 24 and 60 months after surgery. The main inclusion criteria is 1-4 levels of DCM in the subaxial spine, C3-C7, with or without deformity. The REDcap will be used for safe data management. Data will be analyzed in the per protocol (PP) population, defined as randomized patients who are still alive without having emigrated or left the study after five years.
Discussion:
This will be the first randomized controlled trial comparing two of the most common surgical treatments for DCM; the posterior muscle-preserving selective laminectomy and posterior laminectomy with instrumented fusion. The results of the MyRanC study will provide surgical treatment recommendations for DCM. This may result in improvements in surgical treatment and clinical practice regarding DCM.
Age >18 years
1-4 levels of cervical degenerative myelopathy in the subaxial spine, C3-C7, without or with deformity not exceeding
Eligible for both treatments
Ability to understand and read Swedish language
Symptomatic myelopathy with at least one clinical sign of myelopathy
No previous spine surgery
Parallel
Muscle preserving selective laminectomy
Procedure/SurgeryMuscle-preserving selective laminectomy differ from traditional laminectomy by the spinous process split that preserves the deep extensor muscles. The bilateral facet joints are not exposed. After the laminectomy is finished the split fragments of the spinous process are sutured together so that the deep extensor muscles are restored.
Laminectomy with instrumented fusion
Procedure/SurgeryA traditional laminectomy is complemented with lateral mass and/or pedicle screws connected with rods.
The primary endpoint will be reoperation for any reason to reflect whether laminectomy alone or laminectomy with instrumented fusion results in fewer reoperations without increasing the frequency of complications.
Reoperation will be considered in case of: * Postoperative hematoma or reperfusion injury with neurologic deterioration within hours/days after the primary surgery. * Change in sagittal alignment (kyphosis, DJK of more than 40 mm cSVA and/or C2-C7 Cobb \< -10°) with corresponding symptoms of camptocormia/increased pain/neurological deterioration. * ASP defined as degenerative changes on an adjacent level diagnosed with MRI and concomitant symptoms of myelopathy and/or radiculopathy. * Implant failure (clear radiolucency around \>1 screw or rod breakage with increased neck pain and/or neurologic deterioration). * Postoperative infection that requires revision surgery.
Change from baseline in myelopathy score on the patient derived modified Japanese Orthopedic Association scale (P-mJOA) at 2 years.
P-mJOA is a self-administered questionnaire with four domains, measuring motor (upper and lower extremities), sensor (upper extremities) and sphincter dysfunction in patients with cervical degenerative myelopathy. The first domain is scored from zero to five, second domain from zero to seven, third and four domains from zero to three. The maximum score is 18 points, indicating no deficits and the minimum score is zero, total tetraplegia. The minimum clinically important difference (MCID) in mJOA has been reported to be 2 overall with a threshold of 1 in mild myelopathy (mJOA \>14), 2 in moderate myelopathy (mJOA 12-14) and 3 in severe myelopathy (mJOA \<12). Consistency between P-mJOA and mJOA is demonstrated with identical mean scores and a SD of 1.5 together with a strong agreement of 0.83 with the use of intraclass correlation coefficient and the Spearman correlation.
Change from baseline in participants disability score on the Neck disability index (NDI) at 2 years.
Change of at least 17% in the NDI (100 points) compared with baseline (adjustable according to results from own minimal clinically important change results for Neck Disability Index). The NDI range from 0-100% with higher scores indicating severe disability. The MCID is 15%-17% for NDI.
Change from baseline in myelopathy score on the Nurick scale at 2 years.
A six grade system (0-5) based on the 'difficulty in walking'.
Change from baseline in the patient Quality of life five dimensions (EQ-5D index) at 2 years.
EQ-5D index range from -0.5 to 1 with higher scores reflecting a better quality of life).
Click on the lead sponsor to view all of their trials.
Uppsala University Hospital
Lead sponsor
Karolinska Institutet
Collaborator
Linkoeping University
Collaborator
Sahlgrenska University Hospital
Collaborator
