Understanding gaps in the diagnosis of degenerative cervical myelopathy in Aotearoa New Zealand’s primary healthcare – a nationwide cross-sectional survey

Introduction

Degenerative cervical myelopathy (DCM) is the leading cause of adult spinal cord dysfunction globally.¹ It has an estimated global prevalence of 2.3%, which rises to 5% in people over the age of 40 years of age.^2,3 DCM is characterised by cervical spinal cord compression due to degenerative changes, leading to a wide array of upper motor neuron dysfunctions.^3,4 With an aging population seen in Aotearoa New Zealand (NZ) and globally, DCM represents a significant and growing health burden.⁴ Early and accurate diagnosis is critical given the unpredictable disease trajectory, which is often characterised by periods of rapid stepwise symptomatic or functional decline interspersed with periods of quiescence.^5,6 However, diagnostic delays are common, with research suggesting that the average delay from the onset of DCM symptoms to diagnosis is 2.5 years.⁷ This delay undoubtedly contributes to irreversible neurological damage and suboptimal functional and treatment outcomes.^6,8 Timely surgical decompression remains the only evidence-based intervention to halt this disease progression associated with chronic spinal cord compression.⁹

Accurate and prompt diagnosis of DCM largely depends on clinicians’ awareness of the condition and their proficiency in conducting and interpreting neurological assessments.⁵ In NZ, primary care constitutes the main access point for non-emergency health care, encompassing a broad range of clinicians, including general practitioners (GPs), nurse practitioners (NPs), physiotherapists (PTs), chiropractors, and osteopaths. Unlike some healthcare systems where musculoskeletal assessment is largely GP-led, NZ operates under a direct-access model, enabling patients to seek care from allied health professionals without referral. While this decentralised model broadens patient access, it also necessitates strong clinical acumen across primary care disciplines to ensure timely recognition and referral of conditions requiring specialist input, such as DCM.⁵ International evidence suggests that significant gaps in DCM awareness persist among healthcare clinicians, particularly in primary care.^10,11

Despite the key role that these clinicians could play in the early detection of DCM, there is no data on the awareness and diagnostic confidence of primary care clinicians in NZ. This study seeks to address this gap by assessing the current level of DCM awareness and diagnostic confidence among NZ primary care clinicians. Furthermore, it aims to gain an understanding of their current level of knowledge in respect to the understanding of clinical signs and symptoms of this condition and management pathways employed by primary care clinicians with greater familiarity with DCM, to inform future educational and early identification initiatives.

Methods

Results

The survey was conducted between May and October 2023, yielding a total of 336 responses (Fig. 1). Sixteen incomplete responses were excluded, resulting in 320 complete submissions for analysis (3.05% response rate). Of these, 42.8% (n = 137) were from PTs, 33.4% (n = 107) from GPs, 14.1% (n = 45) from chiropractors, 8.8% (n = 28) from NPs, and 0.9% (n = 3) from osteopaths. The majority of respondents (59.1%) had over 10 years of clinical experience, with 36.6% reporting more than 20 years. Responses were evenly distributed between urban (47.1%) and rural or small-town settings (52.8%) across NZ. Most respondents (76.3%) had received their professional qualifications within NZ, and a majority (57.2%) reported no prior formal or informal training in DCM. Further details on the characteristics of survey responses are provided in Table 2.

Fig. 1.

Participant recruitment and flow through the study phases.

Section A: awareness and confidence levels

Section A of the survey was completed by all 320 participants. Among the respondents, the majority indicated ‘average’ (43.1%, n = 138) or ‘limited’ (32.5%, n = 104) awareness of DCM. Notably, 5.9% reported ‘no awareness’ of DCM (n = 19). A higher level of awareness was only indicated by 15.3% (n = 49) responding with ‘very good’ and 3.1% (n = 10) with ‘excellent’ awareness (Fig. 2).

Fig. 2.

Level of condition awareness of DCM among respondents.

Regarding confidence in diagnosing DCM, the majority indicated moderate confidence (36.6%, n = 117). Just over a quarter were ‘slightly’ confident (25.9%, n = 83) and, notably, 22.2% (n = 71) reported ‘not at all confident’. Higher levels of confidence, including ‘very’ or ‘extremely’ confident were only selected by 11.9% (n = 38) and 3.4% (n = 3.4%) respectively (Fig. 3).

Fig. 3.

Level of confidence to detect DCM among respondents.

High levels of clinical experience were positively associated with greater confidence in diagnosing DCM. Clinicians with less than 5 years of clinical experience were more likely to report lower confidence than those with greater than 20 years of clinical experience (τb = 0.140, P = 0.002).

Additionally, previous training in DCM was positively associated with both greater confidence in diagnosing DCM (reporting moderate or very confident) (τb = 0.494, P < 0.05) and higher condition awareness (reporting moderate, very good, or excellent awareness) (τb = 0.488, P < 0.05). Chiropractors and PTs were significantly more likely to report receiving training on DCM compared to GPs and NPs (Cramér’s V = 0.444, P < 0.05).

Discussion

This study provides a detailed evaluation of primary care clinicians’ awareness and understanding of DCM in NZ and highlights critical gaps that could contribute to diagnostic delays. As primary care clinicians are often the first point of contact for musculoskeletal complaints in NZ, their role in recognising progressive conditions like DCM is vital to prevent long-term neurological impairment and disability.^5,6

Notably, our findings revealed significant gaps in awareness of DCM, with 40% of clinicians reporting ‘limited’ or ‘no awareness’ of the condition. Additionally, approximately 50% of respondents reported being ‘slightly’ or ‘not at all’ confident in their ability to diagnose DCM. Similar results have been reported in the United Kingdom, where a recent survey revealed that 57.4% of GPs had very limited awareness of DCM.¹⁰ This low level of awareness is of concern and raises the possibility that people living with DCM may face significant diagnostic delays or even remain undiagnosed within primary care and community settings.¹⁴ Given the progressive nature of DCM, a delay in diagnosis can lead to significant and irreversible neurofunctional consequences.⁶ For this reason, raising condition awareness has been ranked as the number one clinical and research priority for DCM.⁵

Of the clinicians who self-reported at least ‘slightly’ confident in their ability to diagnose DCM, over 70% considered that upper limb paraesthesia, neck pain, and hand dexterity decline were most commonly associated with DCM. Tandem gait disturbance was the clinical sign that most (62%) respondents considered as important in the assessment of patients with suspected DCM. It is possible that the high variability in responses reflects the lack of consensus on the most diagnostic upper motor neuron signs for DCM and highlights the need for standardised diagnostic criteria.¹⁵ Cook et al. found that a cluster of signs, including gait deviation, Hoffman’s sign, Babinski’s sign, and age over 45, provided high specificity for DCM, but these signs were infrequently recognised by our respondents.¹³ Although clinical signs such as Hoffman’s and Babinski’s reflexes have high specificity for DCM, they are frequently overlooked by primary care clinicians.^16,17 Importantly, up to 20% of patients with DCM may not exhibit overt clinical signs despite having DCM symptoms and correlative imaging findings, further complicating early recognition.¹⁸ This reinforces the need for clinicians to avoid being falsely reassured by the absence of clinical examination signs and to maintain a high index of suspicion when assessing patients with neurological symptoms.

Moreover, symptoms often present in a variable and progressive manner over the course of the disease trajectory adding to the challenge of recognising the various non-specific DCM symptoms. This diagnostic ambiguity complicates early recognition and delays appropriate referral for confirmatory diagnostic assessment and investigations.¹⁹ As such, people living with DCM experience average diagnostic delays of 2.5 years, leading to irreversible neurological impairment and disability.^6,7 Surgical decompression remains the only evidence-based intervention, and its efficacy is significantly higher when performed within 4–6 months of symptom onset.^9,20 Surgical decompression for DCM is both efficacious and cost-effective and indicated for moderate, severe, or neurologically progressive cases.^8,9,21 Delayed intervention results in persistent disabilities for 95% of patients and 40% of sufferers are unable to maintain paid employment or maintain independence with daily activities, leading to poorer quality of life compared to other chronic conditions.^6,8,22

Encouragingly, approximately 70% of confidently responding clinicians in this study recognised cervical spine MRI as the definitive confirmatory investigation for DCM, and identified the need for referral to an orthopaedic surgeon, spine surgeon, or neurosurgeon when suspecting DCM. This aligns with current consensus that MRI is the definitive radiological investigation for DCM, with high levels of sensitivity for the evaluation of spinal cord compression, a hallmark radiological feature of DCM.¹⁹ Interestingly, despite low levels of awareness among respondents, many correctly identified the appropriate referral pathway and diagnostic modality. This may reflect an understanding of the role of specialist clinicians in providing diagnostic clarity and access to advanced imaging. However, variations in referral preferences may be influenced by regional differences in access to neurosurgical and orthopaedic services in NZ, where other specialists with musculoskeletal expertise may be more accessible. As such, it is important for primary care clinicians to suspect DCM and recognise its clinical features, as this is a prerequisite for appropriate onward referral to specialist services for definitive diagnostic workup.

Given the aging population seen in NZ and internationally, the prevalence of DCM is expected to rise.¹⁴ With the low levels of awareness and confidence in diagnosing DCM in the present study, strategies to improve the awareness and chances of early detection for at-risk groups are crucial.⁵ In particular, Māori and Pacific people are thought to be at a higher risk due to narrower cervical spinal canal widths when compared to NZ Europeans.²³ There is evidence that routine screening protocols for at-risk populations, such as patients over 45 years old, those with lumbar stenosis, a history of falls and fragility fractures, and Māori and Pacific people, may improve the timeliness of detection.^23–26 Screening tools, such as the modified Japanese Orthopaedic Association scale and the DOWN questionnaires, may aid the assessment of various clinical features of DCM.^27,28 They can be utilised for screening in primary care, in the absence of validated clinical criteria, enabling clinicians to identify DCM, monitor for signs of progression, and refer for imaging when DCM is suspected. Clinicians should exercise a low threshold to refer onwards for diagnostic and surgical workup in the presence of clinical signs and symptoms of DCM, particularly in the aforementioned at-risk patient groups.³

Conclusion

This study highlights significant gaps in the awareness and diagnostic confidence of primary care clinicians in Aotearoa New Zealand regarding degenerative cervical myelopathy. Nearly 40% of clinicians reported low awareness of DCM, and 50% expressed low confidence in their ability to diagnose the condition, likely contributing to the diagnostic delays and disability and irreversible neurological impairment seen in people living with DCM. Clinicians with prior DCM education demonstrated greater awareness and confidence, highlighting the importance of targeted educational interventions. Future research should focus on the development of standardised diagnostic criteria and tailored educational tools to enhance the early recognition of DCM in primary care, particularly for high-risk clinical groups such as older adults, individuals with lumbar spinal stenosis, and Māori and Pacific peoples.