Background Chronic plantar heel pain (CPHP) is the most common cause of heel pain in adults. Pain is described as burning, aching, lancinating, worsening when the patient takes his/her first steps after waking up or after a prolonged rest period. The aim of this study was to determine the differences and relationship between in ultrasound imaging and health-related quality of life (QoL) between individuals with CPHP and healthy controls.

Methods Sixteen patients, 10 males and 6 females (mean age: 45±11 years) with CPHP and 16 age- and gender-matched healthy controls (mean age: 45±11 years) were recruited. Plantar fascia thickness was bilaterally assessed via ultrasound imaging on the calcaneus bone and fascia (1 cm from calcaneus). Further, health-related QoL was assessed using the Foot Health Status Questionnaire (FHSQ).

Results The analysis of variance showed significant differences between both groups and sides, for ultrasound imagining on the calcaneus (group: F=57.528, p<0.001; side: F=11.092, p<0.001) and fascia (group: F=41.280, p<0.001; side: F=7.246, p=0.009): individuals with CPHP had a greater plantar fascia thickness than healthy controls at the both points. A significant interaction between side and group for ultrasound imaging of the calcaneus (F=16.491, p<0.001) and the fascia (F=3.784, p=0.046) was also observed: plantar fascia thickness over the calcaneus and fascia was significantly higher on the affected side as compared with the non-affected side and both sides in healthy controls. The analysis also revealed patients reported significantly lower scores on foot pain, foot function, general foot health, general health, physical activity and social capacity domains (p<0.003) of the QoL questionnaire. No significant differences existed between groups on the domains of shoes and vigour (p>0.05). Significant negative correlations between plantar fascia thickness over the calcaneus and foot function (r=−0.537; p=0.032), shoes (r=−0.619; p=0.01) and physical activity (r=−0.509; p=0.044) domains were observed: the greater the plantar fascia thickness, the lower the QoL in these domains.

Conclusions Our findings revealed greater thickness of the plantar fascia in the affected foot and deterioration of foot and general health domains in patients with CPHP. Higher thickness of the plantar fascia was associated with worse foot function, shoes and physical activity subscales.