[Effects of visual restoration on dynamic plantar pressure features in elder individuals].

OBJECTIVE: To analyze the effects of visual restoration after cataract surgery on plantar pressure and biomechanics of foot in elder individuals.

METHODS: Thirty-two patients [male/female 5/27, (70.1±5.2) years old] with age-related cataract were recruited between October 2016 and December 2019. The footscan system was employed to record the data of plantar pressure during level walking before and 1-month after the cataract surgery. Parameters of peak pressure (PP), impulse (I), pressure-time integral (PTI) and time to peak pressure (TPP) from the regions of the 1st toe (T1), 2nd to 5th toes (T2-5), 1st to 5th metatarsal heads (M1-M5), midfoot (MF), medial hindfoot (HM) and lateral hindfoot (HL) were analyzed respectively.

RESULTS: Post-operatively, the visual function was effectively reconstructed with improved visual acuity in both eyes ( Z =-4.878, -4.801; P < 0.001). The PP ( t =2.266, P =0.031) and I ( t =2.152, P =0.039) values in M2 region on the dominant side (right foot) increased statistically at post-operative phase, while the changes of pressure and temporal para-meters in other regions remained stable. There was laterality in plantar pressure at pre-operative phase, manifested as greater PP values in M1, M2, MF, and HM regions on the dominant sides ( t =-2.414, -2.478, -2.144, -5.269; P < 0.05), greater PP values in T1, M3, M5 and HL regions on the non-dominant sides ( t =4.830, 3.155, 2.686, 3.683; P < 0.05), greater I values in M1, MF, and HM regions on the dominant sides ( t =-2.380, -2.185, -5.320; P < 0.05) and greater I values in T1, M3, M5 and HL regions on the non-dominant sides ( t =4.489, 2.247, 2.838, 3.992; P < 0.05). post-operatively, the pressure tended to be compatible between the two sides in regions of M3 and MF, while the magnitude of laterality in regions of M1 ( Z PP△ = -2.721, P =0.007; Z I△ =-2.581, P =0.010), M2 ( Z PP△ =-2.674, P =0.007; Z I△ =-2.375, P =0.018) and M5 ( Z PP△ =1.991, P =0.046; Z I△ =2.150, P =0.032) was further increased.

CONCLUSION: Changes in plantar pressure after cataract surgery were characterized as increased pressure in the 2nd metatarsal head area on the dominant side. Visual restoration might intensify the laterality in the medial of forefoot on the dominant side and the lateral of forefoot on the non-dominant side.