Effect of surgical correction of equinus foot deformity on triceps surae spasticity in stroke patients

Abstract

Equinus foot deformity (EFD) in stroke can be due to triceps surae (TS) spasticity. Aim of this work is to study the short-term effects of EFD surgical correction on TS spasticity in a sample of hemiplegic patients. A sample of 48 chronic stroke patients, 53(14) years, 19/29 R/L, 6(5) years after lesion, median FAC = 4, walking speed 0.51(0.28) m/s who underwent surgical TS lengthening was included in the study. TS spasticity was assessed through the Modified Tardieu Scale (MTS) before and 1 month after surgery both with the knee extended and flexed at 90 degrees (MTS_KE, MTS_KF). Before/after surgery MTS values were compared using the Wilcoxon test. Percentages of patients with worsened, unchanged and improved MTS scores were also computed and reported. Both MTS_KE and MTS_KF scores significantly decreased one month after surgery ( P = 0.002 and P < 0.001, respectively). MTS_KE score (see Fig. 1 ) worsened in 4 subjects (8%), was stable in 23 (48%) and improved in 21 subjects (44%). MTS_KF score worsened in 2 subjects (3%), was stable in 18 subjects (38%) and improved in 28 subjects (58%). Eight subjects were completely relieved from spasticity. Along with restoring ankle joint range of motion, surgical TS lengthening can also decrease muscle reflex overactivity. This is reasonably due to the reduction in spindle activation during the stretching maneuver consequent to the decrease in muscle shortening, passive tension and stiffness. This should reduce the reflex inputs to the spinal pathways involved in muscle tone control. In conclusion, FS can produce positive changes on TS spasticity in adult stroke survivors. A study on long-term effects is ongoing.