Lower Extremity Motor Deficits Are Underappreciated in Patient-Reported Outcome Measures: Added Value of Objective Outcome Measures

• Main Authors: Martin Nikolaus Stienen, Nicolai Maldaner, Marketa Sosnova, Holger Joswig, Marco Vincenzo Corniola, Luca Regli, Gerhard Hildebrandt, Karl Schaller, Oliver Pascal Gautschi
• Format: Article
• Language: English
• Published: Korean Spinal Neurosurgery Society 2020-03-01
• Series: Neurospine
• Subjects: objective functional impairment; lumbar degenerative disc disease; motor deficit; paresis; disability; patient-reported outcome measure
• Online Access: http://www.e-neurospine.org/upload/pdf/ns-1938368-184.pdf

Objective The patient-reported outcome measure (PROM)-based evaluation in lumbar degenerative disc disease (DDD) is today’s gold standard but has limitations. We studied the impact of lower extremity motor deficits (LEMDs) on PROMs and a new objective outcome measure. Methods We evaluated patients with lumbar DDD from a prospective 2-center database. LEMDs were graded according to the British Medical Research Council (BMRC; 5 [normal] –0 [no movement]). The PROM-based evaluation included pain (visual analogue scale), disability (Oswestry Disability Index [ODI] & Roland-Morris Disability Index [RMDI]), and health-related quality of life (HRQoL; Short-Form 12 physical component summary/mental component summary & EuroQol-5D index). Objective functional impairment (OFI) was determined as age- and sex-adjusted Timed-Up and Go (TUG) test value. Results One hundred five of 375 patients (28.0%) had a LEMD. Patients with LEMD had slightly higher disability (ODI: 52.8 vs. 48.2, p = 0.025; RMDI: 12.6 vs. 11.3, p = 0.034) but similar pain and HRQoL scores. OFI T-scores were significantly higher in patients with LEMD (144.2 vs. 124.3, p = 0.006). When comparing patients with high- (BMRC 0–2) vs. low-grade LEMD (BMRC 3–4), no difference was evident for the PROM-based evaluation (all p > 0.05) but patients with high-grade LEMD had markedly higher OFI T-scores (280.9 vs. 136.0, p = 0.001). Patients with LEMD had longer TUG test times and OFI T-scores than matched controls without LEMDs. Conclusion Our data suggest that PROMs fail to sufficiently account for LEMD-associated disability, which is common and oftentimes bothersome to patients. The objective functional evaluation with the TUG test appears to be more sensitive to LEMD-associated disability. An objective functional evaluation of patients with LEMD appears reasonable.