The natural history of DCM is variable and not fully predictable. Stepwise neurological worsening with interspersed periods of quiescent stability is common; less commonly, slow, steady progression may occur. Some patients experience a benign clinical course with neurological improvement, but complete resolution is infrequent.

Existing degenerative cervical myelopathy (DCM) severity scales have significant shortcomings, creating a strong impetus for the development of a practical measurement tool with sound psychometric properties. The Cervical Myelopathy Severity Index (CMSI) is a new DCM patient-reported outcome measure of symptoms and functional limitations developed using patient and clinician input to inform item generation and reduction. Future work will evaluate the reliability, validity, and responsiveness of the CMSI in relation to existing myelopathy measurement indices.

The cervical myelopathy severity index is a new patient reported outcome measure. Emphasis was placed on capturing patient symptoms and functional limitations. Item generation was informed by qualitative interviews with individuals living with DCM and clinicians to ensure that fluctuating symptom burden and functional impairments important to patients were included, addressing limitations of episodic clinic-based severity scales such as the mJOA.

The modified Japanese Orthopaedic Association (mJOA) score is an 18-point, DCM-specific, clinician-reported outcome measure that quantifies functional disability in the domains of upper-extremity motor, lower-extremity motor, sensory, and sphincter function.[3] The investigation of quantitative clinical measures revealed that most individual instruments had poor sensitivity (i.e., responsiveness) to myelopathic progression…The low sensitivity of the mJOA score demonstrates an important limitation of this tool; although the mJOA score is a highly useful summary measure of the severity of DCM, it is not by itself sufficient to detect all clinically meaningful progression.[3] The absence of worsening on anatomical MRI or in mJOA scores is not sufficient to determine clinical stability.[3] Serial assessments should include mJOA score, grip strength, dexterity, balance, and gait analysis.[3]

Patients with degenerative cervical myelopathy usually deteriorate over time; however, the rate of deterioration is unpredictable and highly variable. ... The symptoms of degenerative cervical myelopathy are persistent and not fluctuating or transient.

"DCM carries a slow progressive course, so while paresthesia is commonly an early symptom, patients may present at any point along the disease course with any number of symptoms, including weakness, sensory change, decreased dexterity, and gait abnormality." The historical description by Lees and Turner "observed a variety of durations of exacerbation, with long periods of latency interspersed," and noted that patients commonly "progressively decline with each exacerbation."

Reported outcome themes in degenerative cervical myelopathy studies included function (reported by 97, 90% of studies), complications (56, 52%), quality of life (31, 29%), pain (29, 27%) and imaging (59, 55%). Only 7 (6%) studies considered all domains in a single publication. The review highlights that existing studies predominantly rely on clinician-reported functional indices and imaging, with relatively sparse and inconsistent use of comprehensive patient-reported outcome measures, suggesting that important aspects of disease burden may not be fully captured in typical clinical assessments.

Mild myelopathy can be defined as mJOA from 15 to 17, moderate as mJOA from 12 to 14 and severe as mJOA from 0 to 11.[1] These categories should be adopted worldwide to standardize clinical assessment of DCM.[1] A mJOA of 14 was determined to be the cut-off between mild and moderate myelopathy and a mJOA of 11 was the cut-off score between moderate and severe disease.[1] Patients in the severe myelopathy group had significantly reduced quality of life and functional status and a greater number of signs and symptoms compared to patients classified as mild or moderate.[1]

Symptoms like neck pain, hand incoordination, and altered hand sensation should heighten suspicion and guide differential diagnosis. ... However, no clear association was observed between certain clinical signs, including the Hoffmann sign, Babinski sign, and hyperreflexia, and the severity of the disease. This finding indicates that while these signs are valuable for diagnosis, they do not necessarily correlate with the severity of DCM.

We identified 78 studies from 18 countries, with 12,450 participants. Time from symptom onset to diagnosis (five studies, n = 897) was 15.0 (5.0–25.0) months. ... Most people with DCM experience symptoms for more than one year before diagnosis. ... There was variation in how studies reported and described duration of symptoms.

"The functional decline in DCM is rarely linear; it can be stable, stepwise, or, particularly in advanced stages, the decline appears to accelerate." It adds: "The majority of individuals with DCM experience a progressive, stepwise deterioration in their symptoms and functional decline… However, the rate of this progression is highly variable: some people with DCM can have a long period of neurological stability without progression and more abrupt deterioration can occur following minor trauma."

Degenerative cervical myelopathy is a spinal disorder resulting in progressive cord compression and neurological deficits that are assessed using the modified Japanese Orthopaedic Association (mJOA) scale.[2] The overall recovery timeline is more generalizable though potentially lacking the specificity patients seek.[2] All four domains show a similar timeline for recovery, but this is a heterogeneous patient population that usually experiences impairment in more than one domain, making it very difficult to apply these results in a practical way when advising patients on what to expect during their recovery.[2] Additionally, a recent study concluded that the mJOA in moderate and severe myelopathy groups demonstrated maximal improvement at three months, without further improvement at twelve months, indicating that the follow-up timeline in our study was sufficient.[2]

"Patients with DCM have a slowly deteriorating disease course and complain of general paresthesia of the upper extremities and clumsiness of the hands." The review notes that "symptoms and signs of myelopathy may vary depending on the involved cervical segment and the degree of compression" and that patients with non-myelopathic spinal cord compression "are likely to progress eventually," with studies showing 8% developing myelopathy at 1 year and about 20% at 4 years.

In discussing natural history, the authors state: "The clinical manifestations of this disease exist on a spectrum of severity; while severely affected patients may be unable to walk or use their hands, mildly affected patients may experience only minor symptoms and have a good quality of life." They emphasize that "current estimates surrounding the natural history of DCM, particularly those individuals with mild or minimal impairment, lack precision" and that "clear predictors of clinical deterioration for those treated with non-operative care are yet to be identified."

Significant improvements were observed across multiple self-reported outcomes following surgery. Total mJOA scores and all subscores significantly improved from baseline to postoperative follow-up. The study examined associations between perioperative patient-reported outcomes and clinical variables, underscoring the role of PROMs in quantifying symptom burden and functional limitations beyond neurological examination alone in patients with DCM.

The modified Japanese Orthopaedic Association (mJOA) scoring system is scored from 0 to 18 points. A lower score represents more severe DCM than a higher score. A score of 15–17 represents mild, 12–14 moderate, and 0–11 severe DCM.[6] Myelopathy.org with AO Spine RECODE-DCM has defined the four that should be used as a minimum standard for future research studies, also known as a ‘core measurement set’, but they are not without limitations.[6] Be mindful of the numbers: most of these scoring systems use categories developed by researchers…in the scoring systems, numbers and categories do not necessarily equate in this simple linear way. Therefore, a change in number or category could mean a very small change or a very large change in DCM.[6] Scoring systems are most commonly used in research studies, to objectively and accurately track changes in symptoms over time, perhaps in response to treatment.[6]

The onset is typically insidious, advancing in a stepwise fashion that leads to functional decline over time. ... When mild DCM is managed conservatively, clinicians should maintain close serial follow-up to monitor progression.

In individuals treated for DCM no clinically meaningful change in PROMs occurred after the 1-year follow-up. The purpose of this study was to investigate whether it is necessary to obtain follow-up data from patients more than 1 year after surgery for DCM. EMS was 14 (12–16) preoperative, 15 (12–17) at the 1-year follow-up, and 15 (12–17) at the 2-year follow-up, with similar stability in NDI and EQ-VAS scores, indicating that once postoperative recovery plateaus, patient-reported severity remains relatively stable over time in most patients.

The ACMS score showed a good correlation with the mJOA score for evaluation of functional disability in the setting of cervical myelopathy.[4] Despite this correlation, a wide variation was noted in the outcomes following surgery. While per Nurick grade only 26% of patients improved, with mJOA and ACMS 50% and 58% of patients, respectively, showed improvement.[4] Thus, use of multiple scoring systems was advised by the authors for assessing outcomes in postoperative patients.[4] One of the major discrepancies between the Nurick and the mJOA scales at follow-up evaluation was that despite any improvement in the mJOA scores, people were regaining employment with a change in occupation.[4]

The rate of progression varies; in some individuals symptoms remain mild over extended periods of time, while in others disease progression accelerates. Frequently not all symptoms are present. For example, pain might be absent and symptoms can be unilateral and vary in severity, even on a daily basis.

Orthobullets notes that cervical myelopathy "tends to be slowly progressive and rarely improves with nonoperative modalities" and that its "progression [is] characterized by step-wise deterioration with periods of stable symptoms."

Patients with myelopathy and those with myeloradiculopathy demonstrated significant and similar improvement in arm and neck pain scores, myelopathy, disability, and quality of life at 3 months that was sustained at 1- and 2-year follow-up intervals. In comparing cohort outcomes, postoperative outcome differences were associated with patient-reported scores at baseline, reinforcing that PROMs capture baseline disease burden that predicts longer-term trajectories beyond single clinic examinations.

The most commonly used measure in cervical spondylotic myelopathy is Nurick grade, followed by modified Japanese Orthopaedic Association Scale (mJOA), visual analogue scale (VAS) for pain, SF-36, and Neck Disability Index (NDI). Most of the studies in the literature assess severity of symptoms at presentation using disability indices, JOA score, and Nurick’s score being the most commonly applied. Although most papers report that more severe baseline scores are associated with worse outcomes, there seems to be no one baseline score index which is considered foolproof, suggesting limitations of these episodic clinic-based scales in fully characterizing disease severity and progression.

The modified Japanese Orthopaedic Association (mJOA) score is widely used to evaluate functional impairment in degenerative cervical myelopathy, but its interpretation can be challenging.[10] In this study, an mJOA score ≤16 is 90% specific for a subsequent diagnosis of DCM in people with neck problems and has potential to be used as an early detection tool.[10] The authors note that while the mJOA is useful for grading severity, clinicians must be cautious in interpreting small changes in score because the minimal clinically important difference and measurement error can influence whether an observed change reflects true clinical fluctuation or normal variability.[10]

In a clinical explanation of natural history, the speaker states that cervical myelopathy "tends to be a slowly progressive condition" and "it does not… get better on its own." He adds that it "generally… progresses over months to years" and that "it's also not the case that people get worse day to day… people tend to get worse in a monotonic fashion… in a stepwise decline," with neurologic level stable for a time then taking a "step" down.

The mJOA scoring system is scored from 0 to 18 points and is used in international guidelines for the management of degenerative cervical myelopathy.[7] A score of 15–17 represents mild, 12–14 moderate, and 0–11 severe DCM.[7] This clinician-reported tool is commonly applied at discrete clinic visits, providing a snapshot of functional status rather than continuous monitoring.[7]

This variability in clinical course can make both the diagnosis and management of DCM challenging for providers. Several patient-reported outcomes have been created to grade and monitor the severity and progression of DCM.

Standardized diagnostic protocols are not well established that can provide prognostic insight in degenerative cervical myelopathy.[5] The mJOA Questionnaire is easy to utilize and can help decision making, track patients’ progress and recovery.[5] Patients complete questions related to upper and lower extremity motor function, sensation, and sphincteric function, and answers are scored and the severity of myelopathy is rated as normal, mild, moderate, or severe.[5] It is important that clinicians inform their patients of the possibility of disease progression and educate them on future relevant symptoms.[5]

If you feel that your symptoms are gradually worsening over time you should contact your healthcare professional to discuss this.

The AO Foundation overview notes that "our understanding of the natural history, development and progression of Degenerative Cervical Myelopathy is limited" and that DCM often shows a "variable disease course" with progression risk that is difficult to predict, particularly in patients with mild disease or asymptomatic cord compression.

In a study of initial symptoms, the authors report that the most commonly self-reported symptoms of DCM include poor balance, clumsiness, neck stiffness, impaired grip strength, and hand numbness, and note that "no one symptom was individually associated with early or late diagnosis." The paper focuses on which symptoms appear first rather than on short-term fluctuation in symptom severity.

Symptomatic deterioration once patients present with myelopathic symptoms has been reported somewhere between 25% and 62% over a 3- to 6.5-year period, and patients initially treated non-operatively have a risk somewhere between 4% and 40% of progression. One quantitative study found that up to 57% of patients had worsening of overall myelopathic symptoms over a period of only two and a half years. The speaker notes that initial presenting severity of myelopathy was the number one predictor of later progression, with patients presenting with mild symptoms progressing at a rate between 10–15% and those with moderate or severe disease progressing at a rate closer to 50% in the near term, indicating a variable, often progressive course that may not be fully characterized by intermittent clinic visits.

The mJOA questionnaire scores motor dysfunction of the upper and lower extremities, sensory function, and sphincter dysfunction on an 18-point scale.[8] Severity categories are defined as: mild myelopathy mJOA from 15 to 17, moderate myelopathy mJOA from 12 to 14, and severe myelopathy mJOA from 0 to 11.[8]

The mJOA scale is an invaluable, internationally recognized tool for physical therapists assessing and managing degenerative cervical myelopathy.[9] However, clinicians should remember that the mJOA provides a structured snapshot of a patient’s function at the time of assessment and may not fully reflect day-to-day fluctuations in symptoms, fatigue, or pain that patients report between visits.[9] For comprehensive management, mJOA scoring should be combined with patient-reported measures and ongoing clinical observation over time.[9]

Age-related spinal changes can be relatively benign – but they also can result in spinal cord dysfunction. ... The group from Toronto used a wide range, not just JOA which is traditionally used, but dash scores, grip strength measures, measures of and function and balance in a more quantitative way and found that up to 57% of patients had quantitative worsening of their overall myelopathic symptoms over a period of only 2.5 years.

Educational and clinical reviews of DCM consistently describe its course as chronic and progressive with stepwise or slowly worsening disability over months to years, rather than fluctuating markedly from day to day. They also emphasize that assessment during episodic clinic visits may underestimate disease impact because manifestations can be subtle, variable across functional domains, and interspersed with periods of relative stability, making prediction of future decline difficult.

At 3-month and 12-month follow-up, satisfaction rates were 86% and 82%, respectively. At 12 months, logistic regression showed the odds of being satisfied were strongly associated with improvements in patient-reported neck disability and quality-of-life scores. The reliance on PROMs to evaluate global treatment success in surgically treated patients with degenerative cervical myelopathy underscores the importance of capturing patient-experienced symptom severity and functional impact, which may differ from impressions formed during isolated clinic encounters.