DR9.2 | Leprosy Neurologic Examination — Summary & Reflection

KEY TAKEAWAYS

The neurological examination is the most important clinical skill in leprosy because nerve damage drives all of its disability and stigma. It serves three roles: a thickened peripheral nerve is a WHO cardinal sign (diagnosis); serial examination detects nerve function impairment (NFI) early enough for corticosteroid rescue; and it yields the WHO disability grade that guides care. Examine a fixed set of cardinal nerves at fixed landmarks — ulnar (medial elbow; most commonly affected; claw of ring + little fingers), common peroneal (fibular neck; foot drop), posterior tibial (behind medial malleolus; plantar sensory loss + clawed toes + ulcer risk), greater auricular (posterior neck triangle), and radial cutaneous (lateral wrist) — assessing thickening, tenderness, sensation (temperature → light touch/monofilament → pinprick), and motor power (MRC 0-5). Convert findings into judgements: NEW sensory/motor loss = NFI (recent onset → urgent corticosteroids; may be silent in borderline disease), and the WHO disability grade (0 = normal; 1 = anaesthesia only; 2 = visible deformity/damage), graded separately for each eye, hand, and foot. Examine at baseline and every visit, document quantitatively on a standard form, and compare serially — that discipline is what prevents permanent deformity.

REFLECT

Return to the woman in the opening scenario whose inflamed skin nearly distracted you from her failing hand. Reflect on how easy it is, in a busy clinic, to examine the skin and forget the nerves — and what specific routine you will adopt so that you palpate every cardinal nerve and test sensation and power at every leprosy visit, even when the patient has no complaint. Consider, too, the discipline of documentation: a finding recorded vaguely today cannot reveal a small new deficit tomorrow. As you build this habit, ask yourself what it means for a patient that the difference between a normal hand and a lifelong claw can come down to whether one clinician, on one ordinary afternoon, took two extra minutes to grade the small muscles of the hand. That is the weight a competent nerve examination carries in leprosy.