Table 3.
Grading | Bland [6] | Modified grading by Hirani |
---|---|---|
Grade1 | Inching, palm/wrist median/ulnar comparison, ring finger double peak | Early: SCV = 45–50 m/s interpeak potentials in digit IV > 0.5 ms, DML < 4.2 ms. Amplitude of sensory ≥5 μV and motor potentials ≥5 mV |
Grade2 | Mild: sensory conduction velocity(SCV) < 40 m/s distal motor latency (DML) < 4.5 ms | Mild sensory: SCV = 40–44 m/s with normal sensory amplitude (NSA), DML, motor nerve action potentials (MNAP) and sensory conduction velocity (SCV) & motor conduction velocity (MCV) |
Grade3 | Moderately severe: DML > 4.5 ms and < 6.5 ms with sensory nerve action potentials (SNAP) preserved |
Mild sensory motor: SCV = 40-44 m/s with NSA, DML > 4.2 ms with normal motor amplitude (NMA) and normal SCV and MCV |
Grade4 | Severe: DML > 4.5 ms and < 6.5 ms with absent SNAP | Moderate sensory: SCV < 40 m/s with NSA, normal DML, NMA, SCV and MCV |
Grade5 | Very severe: DML > 6.5 ms. | Moderate sensory motor: SCV < 40 m/s with NSA, DML > 4.2 ms, MNA and SCV and MCV |
Grade6 | Extremely Severe: motor nerve action potentials (MNAP) < 0.2 mV, | Severe Sensory motor: Absent or < 3 μV SNAP with SCV < 30 m/s with DML > 4.2 ms with either slow or normal MCV and or NMA |
Grade7 | Extremely severe: SNAP and MNAP = absent, but recordable from both median and ulnar 2nd lumbricals with prolonged median 2nd lumbricals response as compare to ulnar lumbricals | |
Grade8 |
Complete: SNAP and MNAP = absent and absent from median 2nd lumbricals and present from ulnar 2nd lumbricals |