Dynamic plantar pressure analysis and midterm outcomes in percutaneous correction for mild hallux valgus.

Mild hallux valgus (HV), which can lead to alteration of the plantar pressure pattern with an overpressure under the hallux, can be repaired percutaneously. Our goals were to determine whether the percutaneous distal soft tissue release (DSTR)-Akin procedure restores the loading pattern and to evaluate which are the determinants of the measures of post-operative outcome. Seventy-nine percutaneous DSTR-Akin procedures were performed in the same number of patients. The plantar pressure patterns were evaluated using the BioFoot/IBV® in-shoe system and compared with measurements from 98 controls. The clinical and radiological outcome parameters measured were the pre- and post-operative AOFAS scores, and the first intermetatarsal, hallux abductus, and first metatarsal-hallux declination angles (FIMA, HAA, FMHDA) in weight-bearing radiographs. The mean follow-up was 28.1 (range 24-33) months. The plantar pressure analysis showed a significant decrease (328-152 kPa, p = 0.001) in the mean pressure under the hallux. Significant improvements occurred in the AOFAS scores, and angular deviations were reduced. The post-operative HAA correlated with the mean pressure under the 1st toe (r(2)  = 0.132, p < 0.001). The DSTR-Akin percutaneous technique in mild HV restores physiological patterns of pressure on the hallux and achieves significant correction of radiographic angles and commensurate improvement in clinical status.