Open Access

Camilla Kapitza, Nikolaus Ballenberger, Kerstin Lüdtke, Brigitte Tampin

• Background Spine-related neck-arm pain is heterogenous in its clinical presentation and pain-types (nociceptive/neuropathic). A clinical-framework for spine-related pain differentiates between (i) somatic referred pain, ii) heightened nerve mechanosensitivity, both conditions are per definition nociceptive pain (NoP) and iii) radicular pain as well as iv) radiculopathy. Radicular pain with radiculopathy meets the criteria for neuropathic pain (NeP). Purpose The aim was to investigate if NeP-characteristics differ between the group somatic referred pain/heightened nerve mechanosensitivity (group A) and the group radicular pain/radiculopathy (group B), using the NeP screening tool painDETECT (PD-Q). For the purpose of this study, group A was defined as having NoP, and group B as having NeP. Methods One hundred and thirteen persons with unilateral spine-related neck-arm pain were clinically assessed using bedside neurological examination and classified into subgroups A and B. Maximal pain area (MPA), average pain severity during the last 4 weeks, sleep quality (numerical-rating-scale), symptom duration (weeks), neck disability index (NDI) and PD-Q were recorded. The PD-Q includes seven weighted sensory descriptors (burning, tingling/pricking, light touch, electric shocks, cold/heat pain, numbness, pressure). The lowest weight is 0 (no experience of the sensation) and the highest weight is 5 (sensation is felt very strongly). PD-Q classifies patients into 3 groups, unlikely (0-12), unclear (13-18) and likely NeP (19-38). For this study, a score ≤ 18 was defined as unlikely and >19 as likely NeP. Results Based on the clinical-framework, 52 persons were classified into group A (37 females; mean age 46,1 ± 11,8), of which 48 (91,3%) were classified by PD-Q as unlikely NeP. Sixty-one persons were clinically classified into group B (34 females, mean age 48,7 ± 11,3), of which PD-Q classified 14 (23%) as likely NeP. 84,6% in group A reported the neck as MPA. In group B 63,9% indicated the arm as MPA. There were significant differences in symptom duration (A: mean 207,8 ± 272,3; B: 64,2 ± 154,1, p=< 0,001) and the following PD-Q descriptors: burning (A: 15,6%, B: 38,% p=0,005), tingling/pricking (A: 39,1%, B: 79,6%, p= < 0,001) and numbness (A: 20,3%, B: 38,8% p=0,032). All other descriptors showed no statistically significant difference. Conclusions The majority of people in group A (75%) reported the neck as their MPA whereby the majority of persons in group B (61%) reported arm pain. Typical NeP characteristics were significantly more common in group B compared to group A, supporting the suggestion that the clinical presentations of radicular pain/radiculopathy are likely associated with the presence of NeP. The PD-Q identified 89.1% of the clinically classified NoP subjects as unlikely neuropathic, but only 24.5% of those in the radicular/radiculopathy group as having likely NeP, suggesting low diagnostic accuracy in this population. Implications It is important to know whether a person with spine-related arm pain has NeP, in order to implement appropriate treatment. The location of the MPA and reported pain descriptors may assist clinicians in the diagnostic work-up of persons with spine-related neck-arm pain.