Objective:

To evaluate the prevalence of various LSP etiologies, analyze clinical/electrodiagnostic(EDx) features, and describe patient outcomes.

Background:

Lumbosacral plexopathy (LSP) results from a spectrum of etiologies, causing significant functional impairment. Limited data exist on the prevalence, diagnostic features, and long-term outcomes. This study aimed to elucidate etiologies, clinical findings, EDx characteristics, and outcomes of LSP. 

Design/Methods:

We retrospectively reviewed records of patients diagnosed with LSP at our center from January 2000 to September 2024. Definite LSP was defined by weakness in muscles innervated by at least two lumbosacral nerves, with EDx evidence of multi-nerve involvement with asymmetric sensory involvement or corresponding imaging abnormalities. Probable LSP met similar clinical criteria but lacked definitive EDx or imaging confirmation and was not attributable to radiculopathy or other mimics.

Results:

Of 1,139 screened records, 124 patients met criteria for LSP (38 definite[30.6%], 86 probable[69.4%]). Median age was 61.8 years(mean±SD: 61.8±15.0), and 59(47.6%) were female. Symptom onset was acute in 47(37.9%), subacute in 9(7.3%), and chronic in 68(54.8%). Sensorimotor symptoms predominated(71.0%) in our cohort. Leading etiologies included diabetes(34.7%), post-operative injury(25.8%), and idiopathic case(14.5%). EDx was performed a median of 4.0 months after symptom onset. Sural sensory nerve action potentials were often absent(median 0 µV), and abnormal spontaneous activity on needle EMG was observed in 89 of 94 cases(94.7%). Recruitment abnormalities were moderate in 68(72.3%), severe in 12(12.8%), mild in 8(8.5%); in  (3.2%), motor units were absent. Management included neuropathic pain therapie (51.6%), physical therapy(62.1%), corticosteroids (3.2%), and immunotherapies(4.0%). Among 85 patients with follow-up, 35(41.2%) achieved full or near-complete recovery.

Conclusions:

Diabetes was the most common etiology of LSP, followed by post-operative and idiopathic causes. While partial sensorimotor improvement was frequent, full recovery was uncommon and often delayed. These findings underscore the importance of early recognition and comprehensive evaluation to guide tailored therapeutic strategies for optimizing outcomes in LSP.