Objectives: The purpose of this study was to correlate findings on small vessel vascularity between computerised findings and Newman's scaling using power Doppler ultrasonography (PDU) imaging and its predictive value in patients with plantar fasciitis.
Methods: PDU was performed on 44 patients (age range 30-66 years; mean age 48 years) with plantar fasciitis and 46 healthy subjects (age range 18-61 years; mean age 36 years). The vascularity was quantified using ultrasound images by a customised software program and graded by Newman's grading scale. Vascular index (VI) was calculated from the software program as the ratio of the number of colour pixels to the total number of pixels within a standardised selected area of proximal plantar fascia. The 46 healthy subjects were examined on 2 occasions 7-10 days apart, and 18 of them were assessed by 2 examiners. Statistical analyses were performed using intraclass correlation coefficient and linear regression analysis.
Results: Good correlation was found between the averaged VI ratios and Newman's qualitative scale (ρ=0.70; p<0.001). Intratester and intertester reliability were 0.89 and 0.61, respectively. Furthermore, higher VI was correlated with less reduction in pain after physiotherapeutic intervention.
Conclusions: The computerised VI not only has a high level of concordance with the Newman grading scale but is also reliable in reflecting the vascularity of proximal plantar fascia, and can predict pain reduction after intervention. This index can be used to characterise the changes in vascularity of patients with plantar fasciitis, and it may also be helpful for evaluating treatment and monitoring the progress after intervention in future studies.