Los Angeles Motor Scale (LAMS) for Stroke Severity
Los Angeles Motor Scale (LAMS). Prehospital and emergency department tool for rapid assessment of stroke severity and identification of Large Vessel Occlusion (LVO). Three components: facial droop, arm drift, and grip strength. Score 0-5; score above 3 predicts LVO with sensitivity 81% and specificity 89%. Used to guide activation of comprehensive stroke centres with thrombectomy capability. Developed by Llanes et al. 2004.
Score interpretation
LAMS 0-3 -- lower probability of large vessel occlusion
→ Transport to nearest appropriate stroke unit (primary or comprehensive stroke centre); activate stroke team; CT/CT angiography on arrival; if stroke symptoms within 4.5 hours: thrombolysis eligibility assessment (tPA or tenecteplase); NIHSS assessment in ED; secondary prevention workup; note: LAMS 0-3 does not exclude LVO -- CTA is definitive; FAST signs for public education.
LAMS 4-5 -- high probability of large vessel occlusion; urgent comprehensive stroke centre activation
→ BYPASS primary stroke centre to comprehensive stroke centre (CSC) with 24/7 mechanical thrombectomy capability if within 30-minute travel time differential; pre-alert CSC team en route; immediate CT/CT angiography on arrival; if LVO confirmed on CTA: direct to angio suite for mechanical thrombectomy; consider bridging thrombolysis (alteplase or tenecteplase 0.25 mg/kg IV, max 25 mg) prior to thrombectomy if no contraindications; note: LAMS used prehospital by paramedics and in ED -- in-hospital tools (NIHSS, CTA) are definitive; tPA/TNK bolus should not delay transport to CSC.
Interpretation bands for the LAMS Scale. Apply clinical judgement and local guidance.
References
- Llanes JN et al. The Los Angeles Motor Scale (LAMS): a new measure to characterize stroke severity in the field. Prehosp Emerg Care. 2004;8(1):46-50.
- Zhao W et al. A systematic review and meta-analysis of prehospital stroke scales in identifying large vessel occlusion stroke. Stroke. 2021;52(12):e819-e828.
Related
Curated clinical cross-links plus same-class fallbacks.
- Aspirin (Loading Dose) · Antiplatelet — ACS / Ischaemic Stroke
- Alteplase (tPA) · Thrombolytic — Ischaemic Stroke / Massive PE
- Edoxaban (AF Stroke Prevention / VTE) · Direct Factor Xa Inhibitor (DOAC)
- Clopidogrel (Stroke/TIA Secondary Prevention) · Antiplatelet (P2Y12 Inhibitor)
- Riluzole · Neuroprotective Agent — ALS/Motor Neurone Disease
- Dabigatran (Stroke Prevention — AF) · Direct Oral Anticoagulant — Thrombin Inhibitor
- Acute Stroke / TIA Assessment · NICE NG128; RCP Stroke Guidelines 2023
- Status Epilepticus (Adults) · NICE CG137; ESEM guidelines; RCP Neurology Guidelines
- Suspected Subarachnoid Haemorrhage · NICE NG228; RCEM 2023; AHA/ASA 2023
- Adult Head Injury · NICE NG232 (2023)
- Bell's Palsy / Facial Nerve Palsy · ENT UK 2017; AAN
- Vertigo Workup · ENT UK; NICE CKS
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.