Use of Assessment Tools in Cervical Spondylotic Myelopathy—Results of An Anonymized Survey Among Indian Spine Surgeons
Correspondence Address: Source of Support: None, Conflict of Interest: None DOI: 10.4103/0028-3886.360923
Source of Support: None, Conflict of Interest: None
Keywords: Cervical compressive myelopathy, CSM assessment tools, Nuricks's grade
Cervical spondylotic myelopathy (CSM) is the commonest cause of cervical myelopathy. CSM results in great disability and is a big economic burden for society. Myelopathy occurs because of both static factors and dynamic factors. The compressed spinal cord can undergo demyelination or necrosis depending on the duration of compression, apart from various other known and unknown factors., The degree of the compression is variable among patients, as are the symptoms.
Assessment of patient's deficits and clinical status is essential for execution of proper management strategies including the surgical plan. The assessment scales can be used to assess the severity of disease in a quantitative manner. Assessment becomes more objective with the use of assessment scales. Many of these scales combine different modalities like motor, sensory, and autonomic., They can also help in assessing the change in clinical condition of the patient in a quantitative manner. One can also get help in deciding when to intervene surgically in a quantitative way with the help of these scales. It is possible for the surgeon to objectively ascertain the benefit received from surgery. We aimed to survey the spine surgeons in India regarding the use of any assessment scales in their practice. This will also help us in raising awareness about the assessment scales.
We designed an online questionnaire using the application “Google Forms.” The link to the questionnaire was widely circulated among physicians and surgeons involved in the care of patients with CSM using e-mail and various social media platforms. The respondents were completely anonymized to ensure a free and frank elicitation of responses. The questionnaire consisted of 10 questions covering the specialty and experience of treating the CSM patients and their preference for various parameters in assessing these patients. The perceptions of the respondents regarding these activities were graded on a 5-point Likert scale, wherever applicable. The estimated number of spine surgeons who were sent out this survey is around 700, an estimate based on total e-mails sent and the number of members in the groups where the survey was shared. Statistical analysis was done using the statistical programming language R. Mean Likert scale scores were compared between groups by using an independent sample t-test.
We received 163 responses. Most of the respondents (three-fourths) were from neurosurgery background [Table 1]. There were two neurologists as well who responded to the survey while there were four others (general physicians, rheumatologists) who responded. Forty-five percent of respondents worked in private sector hospitals while two-fifths of the respondents worked in academic government hospitals [Table 2]. We had respondents with variable experience in treating patients with CSM after completion of residency, about 45% of the respondents had more than 10 years of experience. Another 21% of the respondents had 5–10 years of experience, while one-fourth had an experience of less than 5 years following completion of residency. Hence, doctors who were trained at different times were included in the study and accordingly the practices followed in residency across many decades are reflected in this survey.
About 90% of the respondents reported that they are aware of the use of the assessment scales in CSM while only 57% of them used any one of the assessment scales in management of CSM [Table 3] and [Table 4]. History, examination findings, and radiological information are used by most of the respondents while only 57% gave significant importance to assessment scales in assessing patients of CSM or while making treatment plan for these patients.
Maximum number of respondents (85%) were aware of Nurick's grade among all the assessment scales [Table 5]. Modified Japanese orthopedic association score (mJOA) (65%) was the second most popular assessment scale. Following the same trend, Nurick's was the commonest assessment scale to be used by spine surgeons in India and about 70% of the respondents reported that they use Nurick's scale in their practice [Table 6]. mJOA was used by 46.3% of the respondents.
Across clinical disciplines, 80% of neurosurgeons were aware of Nurick's grade while only 55% were aware of mJOA [Figure 1] and [Figure 2]. On the other hand, 89% of orthopedic spine surgeons were aware of both Nurick's and mJOA. Thus, the awareness of mJOA was more in orthopedic surgeons as compared to neurosurgeons. However, the figures were different when it came to the use of these assessment scales in clinical practice. The mJOA was more frequently used than Nurick's grade by neurosurgeons (62% vs. 30%, respectively) whereas the orthopods favored both the Nurick's and the mJOA [Figure 3] and [Figure 4]. [Figure 5] summarizes the comparison of perceived importance of various assessments tools for diagnosis of CSM by different specialists. More number of orthopedic spine surgeons use any of the assessment scales compared to neurosurgeons and this finding was statistically significant [Figure 6]. There was no statistically significant difference when the use of assessment scales was compared as per the experience of the surgeons [Figure 7].
The commonest reason for surgeons not using any of these assessment scales despite being aware of these scales was their perception that it is very time-consuming to complete these assessment scales (58.8% of respondents thought so) [Table 7]. The second commonest reason was that all the assessment tools are too complex for patients to understand (33.3%). One-fourth of the respondents believed that these assessment scales are only for research purpose and not relevant for clinical work.
CSM is a degenerative disease of the cervical spine and remains a common pathology of spinal cord in persons older than 55. Matz et al. studied the natural history of CSM and described multiple patterns of disease progression., The patterns identified by them included slow manifestation, stepwise decline, and a long period of quiescence. CSM can present in multiple ways as the extent of involvement of a modality is variable in different patients. Hence, a single outcome measure is insufficient to quantify the different type of neurological deficits seen in CSM and use of more than one parameter assessing different modalities will be required for an assessment scale to be sensitive enough to identify patients with different severity of CSM. Surgery is frequently used to halt the progression of CSM, and the various options are anterior or posterior decompression of spine with or without fixation.
Properties of an ideal scale
Ten components of an ideal scale for any disease are well described in literature., Some of these include equal distribution, quantifiability, validity, sensitivity, responsiveness, ease to administer, high interrater and intrarater reliability, relevance, one dimensional with no hierarchy between components and homogeneity. An ideal scale for any disease should address the pathophysiology, natural history of the disease, and signs and symptoms of the disease. Hence, an ideal scale for CSM must assess the function served by the tracts, which get injured in CSM like the lateral corticospinal tracts, and the anterior and posterior spinocerebellar tracts. The natural history of the disease also differs among the disease population. Hence, an ideal scale should be able to identify patients in early stage as well as advanced stages of disease. A scale which uses only motor power and not subtle signs will miss the patients in the initial stages of the natural course of CSM. The classical symptoms of CSM include neck pain, neck stiffness, and brachialgia. These symptoms can be assessed indirectly by assessing the disability arising due to these symptoms.,,
Need of an assessment scale
Currently most of the spinal surgeons rely on the history and clinical examination, which includes motor power. Many times the objective assessment of motor power remains unchanged after surgical decompression even though the patient reports significant improvement in his or her ability to carry out daily activities. This happens primarily due to reduction in the muscle tone. If one uses only muscle power and tone for assessment of these patients in preoperative and postoperative, it is very difficult to get an objective idea of the improvement following surgery. However, an assessment scale, if used, can quantify the improvement noticed because of reduced tone in terms of increased ability of the patient to carry out daily activities. For example in mJOA the patient is assessed on the basis of his ability to carry out multiple daily routine activities by his upper limbs and lower limbs. It also incorporates sensory and bowel/bladder function. Hence by using a mJOA, one can get an objective score for the improvement which has occurred following surgery. The importance of objective scores cannot be underrated in medical sciences where past experiences are the best kind of evidence which one has, and these guide surgeons in their future practice.
Common scales in use
There are many scales in use for CSM like mJOA scale, Nurick grade, neck disability index (NDI), the 30-m walk test, 10-m walk test, European Myelopathy Scale, visual analogue scale (VAS), Short Form-36 Health Survey (SF-36), Myelopathy Disability Index (MDI), Berg Balance Scale (BBS), Graded Redefined Assessment of Strength Sensibility and Prehension (GRASSP), GAITRite Analysis, Grip dynamometer, BBS, QuickDASH, Cervical spine outcomes questionnaires, Bournemouth questionnaire and short form-12.,,,,,,,,,,
Many studies have been conducted to find out an ideal scale, but no definitive result has come out leading to persistence of the multiple scores—each tailored for specific purposes. Out of these the modified GRASSP, QuickDASH, and the grip dynamometer assess the upper limb function. GAITRite analysis and the walk tests assess the lower limb function. MDI and BBS assess the trunk and pelvis function. Multiple studies reported significant correlations with the Nurick grade: lower limb mJOA, total mJOA, JOA, European myelopathy score, and patient-reported outcomes.,,
The results of different assessment scales can be different in the same patient as different assessment scales assess different aspects of the disease and might not correlate well with the actual disease. One study using Nurick grade got wrong results like no correlation between the duration of symptoms and poor outcome, etc. The authors believed that these results might have occurred due to the shortcomings in the Nurick grade, as it relies too much on mobility and employment of the patient while the other aspects are ignored. Thus, even one of the commonly used outcome measures has flaws and cannot be relied upon as a single-outcome measure. Ancillary measures to detect some additional aspects of the disease should be used to get a more accurate assessment. Outcome measures with high responsiveness are required to define the patients with mild disease. Using ancillary measures will also help in establishing predictors of recovery and outcome after surgery.
The literature regarding the acceptance of these tools in general practice is sparse. Mostly they are limited to research purposes. This study provides an insight into their acceptance by the spinal surgeons in the management of patients of CSM in India. We have explored the knowledge, utility, and hindrance regarding usage of these tools. As we found out, history, examination, and radiology were given more importance for diagnosis of CSM than assessment tools and correspondingly contributed much more heavily to diagnosis in clinical practice. Cloney et al. have reported good correlation between radiology and mJOA and Nurick's grade.
Kalsi-Ryan et al. studied the frequency of use of CSM outcome measures in the studies published in literature. They found that the most commonly used measure is Nurick grade (cited in 62 studies), followed by mJOA (cited in 57 studies), VAS for pain (27 studies), SF-36 Health Survey (18 studies), and NDI (10 studies). This matches the results of our survey.
About 90% of our respondents were aware of any one of these tools while converting to practice only 57% of them used any one of these assessment tools in their practice, the most common reasons of this being the time constraint and complexity of these tools. SF-36 includes over 36 responses and JOA over 28 responses and takes up precious outpatient time. While Nurick's grade is simpler and faster, many studies have found poor correlation between outcome and Nurick's grade as it fails to take into account duration of ailment. We agree that these scores can be time-consuming and unsuitable for out-patient assessment, especially in regions with high patient load such as in India.
Most of these scales are observer administered and not self-administered. If we can have a scale which is simple for the patient to understand and can be self-administered, it can be more widely used as per the concerns raised by the respondents in this survey.
Singh et al. surveyed clinicians in the United Kingdom to determine their attitude regarding the use of quantitative assessment scales in the management of CSM and use of these scales in their clinical practice. They found that all the 117 participating clinicians gave almost equal importance to clinical history, examination, radiological imaging, and quantitative functional assessment in their practice. However, only 22 (19%) of clinicians used an assessment scale in the management of CSM patients. This survey was done in 2005 and we think the practice has changed since then.
Despite the presence of so many parameters, there is still no gold standard outcome measure which can accurately assess the severity of the disease across all ranges of disease severity and detect changes in a patient that occur over the time including deterioration and improvement both. This makes it challenging to have standard guidelines and make prognosis predictor models. Most of the clinicians dealing with patients with CSM currently use mJOA and Nurick's grade. However, there is a disadvantage of using only these two as the patients with mild disease are not evaluated adequately by these two. On the other hand, SF-36 and NDI can better assess the functional status and are useful in assessing patients with postoperative period. It has been recommended to use few assessment scales together in order to get accurate assessment. Ziteli et al recommended use of combination of variables including mJOA, Nurick's grade, and MDI for measuring outcome. Singh et al. recommended that functional measures should be used along with quantitative measures and functional quality life measures. They recommended mJOA, Nurick's grade, and MDI are good to assess the functional status while one of the walking tests can be used for quantitative measurement and SF-36 is a good functional quality life measure.
This study's respondents included a large variety of practitioners handling patients of CSM giving a good representation of the general practice. Furthermore, it was open-ended and anonymous as it was conducted through electronic mail. But the downside could have been self-reporting bias and we didn't take into account the patient scenarios/presentation which would have made the survey more specific.
Assessment scales have a role in the management and follow-up of CSM patients. Only 57% of doctors dealing with CSM patients use any of the assessment scales in their practice while 90% of them are aware of these tools with time constraint being the commonest cause of them not using these tools. A self-administered tool can be helpful in this regard.
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Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]