Is Shoulder Pain and Disability Index a Prognostic Factor for Neuropathic Shoulder Pain?

Abstract

Introduction So far, investigations in patients with rotator cuff diseases have used pain measurement tools such as visual analog scale (VAS) for nociceptive pain as well as neuropathic pain (NeuP) specialized ones like Douleur Neuropathique 4 Question (DN4) and Pain Detect. The study's goal was to look at the existence of NeuP in patients with chronic shoulder pain, as well as variables that may be predictive of its progression. Methods There were 112 outpatients in all. Current and previous pain intensity levels were documented with the numerical rating scale (NRS), the Shoulder Pain and Disability Index (SPADI) was used to assess pain and disability levels, and the S-LANSS (self-completed Leeds Assessment of Neuropathic Symptoms and Signs Pain Scale) was used to diagnose NeuP. The Pearson Chi-Square test was employed to check for any relationships between variables. The Mann-Whitney U test was also employed to check for between-group differences (with or without NeuP). To investigate factors that may be utilized as a prognostic for NeuP, logistic regression was performed, with those components (from the univariate analysis) that were statistically significant being included. Results According to the S-LANSS questionnaire for NeuP diagnosis, 21 patients had NeuP. According to S-LANSS, chi-square test findings revealed that NeuP is independent of sex, smoking, size, and location or rotator cuff tear. Univariate analysis with Mann-Whitney U test revealed statistically significant differences in SPADI and NRS scores between the two patient groups (p < 0.001). Α multivariate analysis using S-LANSS as the binary dependent variable and NRS currently, NRS average last month and SPADI total score as independent variables (with statistical significance) revealed that total SPADI score may be considered as an independent prognostic factor for NeuP (odds ratio = 1.189, p < 0.001). Limitations Due to the limited number of patients who participated in the study, the findings were deemed insufficient in terms of statistical power. In particular, the power analysis of the study (type I error probability being [a] = .05) was less than 80% (for the total SPADI score), hence relatively small. As a result, there is a limited probability of a type I error. Conclusions Using S-LANSS, we discovered that 18.8% of patients with rotator cuff tears had NeuP. The SPADI scores (pain and disability) in the NeuP group were substantially greater than in the nociceptive pain group. As previous studies have suggested utilizing certain levels of the VAS for pain assessment and specialized questionnaires for NeuP evaluation, we recommend that SPADI be included as a tool for emphasizing the neuropathic features of shoulder pain.

Keywords: disability; neuropathic pain; rotator cuff; shoulder; spadi.

Figure 1. Flow chart with the number of patients enrolled.