Introduction: The Disabilities of the Arm, Shoulder and Hand (DASH) score is a self-reported outcome measure of upper extremity disability that is increasingly used in patients with neck pain and/or upper extremity disorders. In this retrospective concurrent validity study, we examine the validity and agreement of the DASH score compared to the commonly used neck-specific Neck Disability Index (NDI) and Visual Analogue Scale (VAS) for Pain in patients undergoing cervical spine surgery.
Methods: We retrospectively analyzed 432 patients undergoing cervical decompression and fusion surgery at our institution from 2013 to 2016 (Table 1). DASH, NDI, and VAS scores were collected for each patient before undergoing surgery, and at subsequent follow-up appointments. We calculated Pearson’s correlation coefficients between the self-reported outcome measures using preoperative, mean postoperative, and improvement scores. Overall analysis including all patients was performed, and subgroup analysis for patients with predominant radiculopathy or myelopathy symptoms. Bland-Altman analysis was used to evaluate for agreement between the DASH and NDI scores.
Results: Overall analysis showed positive correlations between DASH and NDI pre-operatively and post-operatively (r=0.77 and r=0.41 respectively, p<0.001; Table 2), and between DASH and VAS (r=0.33 pre-operatively and r=0.43 post-operatively, p<0.001). Subgroup analysis in radiculopathy and myelopathy patients demonstrated similar concordance (Tables 3 and 4): Radiculopathy DASH vs. NDI (r=0.8, p<0.001 preoperatively and r=0.23, p<0.01 post-operatively) and Myelopathy DASH vs. NDI (r=0.76, p<0.001 preoperatively and r=0.82, p<0.01 post-operatively). Bland-Altman plots showed agreement between the DASH and NDI (Figure 1). Mean DASH scores were higher by 0.7% to 3.03% compared to the NDI.
Conclusions: Neck pain and upper extremity disability evaluations using the DASH questionnaire were shown to have moderate to high correlations with scores from the neck-specific NDI and VAS for pain. Our results highlight the feasibility of using DASH to track quality-of-life and functional improvement after cervical spine surgery.
Patient Care: Neck pain and upper extremity disability are common and particularly burdensome problems affecting a significant number of adults. Our research is part of a larger effort to develop and validate effective measures to track patient-reported outcomes, functional improvement, and quality of life metrics in patients undergoing cervical spine surgery. The results of our study underscore the close relationship between neck pain and upper extremity disability, and shed light on a thorough patient-centered questionnaire (DASH).
Learning Objectives: By the conclusion of this session, participants should be able to:
1) Describe the relationship between the DASH, NDI and VAS as measures of neck and upper extremity disability.
2) Discuss, in small groups, the potential for using self-reported patient outcome measures to evaluate and track functional improvement in patients undergoing cervical spine surgery.
3) Identify appropriately validated and commonly used questionnaires to measure patient upper extremity disability and neck pain.