Table 2.

Stages of familial amyloid polyneuropathy for locomotion.

Coutinho et al. [1980]		Duration of stage	Yamamoto et al. [2007]
Stage 1	The disease is limited to the lower limbs Walking without any help. Slight weakness of the extensors of the big toes.	5.6 ± 2.8 years	PND I	Sensory disturbances in extremities Preserved walking capacity
Stage 2	Motor signs progress in lower limbs with steppage and distal amyotrophies, the muscles of the hands begin to be wasted and weak. The patient is by then obviously handicapped but can still move around, although needing help.	4.8 ± 3.6 years	PND II PND IIIa PND IIIb	Difficulties walking but without the need for a walking stick One stick or one crutch required for walking. Two sticks or two crutches required for walking
Stage 3	The patient is bedridden or confined to a wheelchair, generalized weakness and areflexia.	2.3 ± 3.1 years	PND IV	Patient confined to a wheelchair or a bed

PND, a modified polyneuropathy disability score.