Table 2

Summary of neurophysiological studies

Family noPatientAge (years) at assessmentMedian motor (APB)Ulnar motor (FDIO)Peroneal motor (EDB)Tibial motor (AH)Median sensoryUlnar sensoryRadial sensorySural sensoryEMG/comments
Amp (mV)CV (m/s)Amp (mV)CV (m/s)Amp (mV)CV (m/s)Amp (mV)CV (m/s)Amp (µV)CV (m/s)Amp (µV)CV (m/s)Amp (µV)CV (m/s)Amp (µV)CV (m/s)
UK1IV.12410.74610.4 (ADM)541.9351.26563522056ANAProximal and distal, non-length-dependent chronic denervation in the UL and LL; some equivocal myopathic change in some muscles
III.2566.75412.1 (ADM)510.5413511521160ANAProximal and distal non-length-dependent chronic denervation
II.1781.3395.9 (ADM)54ANAANAANAANAANAANAProximal and distal non-length-dependent chronic denervation
UK2IV.21910.7448.5 (ADM)512431.118507603164543Limited EMG study (tibialis anterior) was unremarkable
UK3III.2446.5427.1 (ADM)461.9411.5252ANA652ANAProminent chronic denervation in UL and LL, largely length-dependent
UK4IV.7536.7508.4 (ADM)552.3330.9NA10523531957236Prominent chronic non-length-dependent denervation, similar distally and proximally, with features of acute denervation
IV.8509.8507.9 (ADM)592431NA5574561462ANAChronic denervation, not convincingly length-dependent and similar distally and proximally; with features of acute denervation
FR1II.56812.153.80.1231.1ANAANAANANon-length-dependent chronic denervation in the UL and LL
III.2557.454.3543.213.7404.539Non-length-dependent chronic denervation in the UL and LL
III.35110.6657.6522.43112385451144231Non-length-dependent chronic denervation in the UL and LL
III.4508.250ANAANAANANon-length-dependent chronic denervation in the LL
III.5496.445.18.549.8ANAANAANAANAFeatures consistent with chronic denervation distally in the LL
III.6467.844.211.4502.430.86.3383.343ANANon-length-dependent chronic denervation in the LL
III.7443.451.1943.64.141.14.2397.7414.533Non-length-dependent chronic denervation in the LL
IV.12313.075311.81560.773747.8375.43914.3389.625Features consistent with chronic denervation distally in the LL
IV.5238.255.25.839.110.110.348ANAFeatures consistent with chronic denervation distally in the LL
IV.617850.26.538.511.514.7474.140Features consistent with chronic denervation distally in the LL
FR2II.1235.77546.8591.35343.540ANA540ANANon-length-dependent chronic denervation
FR3II.3241045.16.746244.31.238.62.141.94.840.7Chronic denervation, equally prominent distally and proximally, with features of acute denervation
CN1II.22819.444.712.648.31.230.67.139.81041.3839.37.750634.6Non-length-dependent chronic denervation
  • All motor amplitudes are responses to distal stimulation (wrist and ankle).

  • –, not available; A, absent; ADM, abductor digiti minimi; AH, abductor hallucis; Amp, amplitude; APB, abductor pollicis brevis; CV, conduction velocity; EDB, extensor digitorum brevis; EMG, electromyography; FDIO, first dorsal interosseous; LL, lower limb; NA, not applicable; UL, upper limb.