The main aim of this study is to investigate the effects of dry cupping on calf muscle trigger points in patients with plantar heel pain. A secondary aim is to examine the correlation between several outcome measures in those patients.

Plantar heel pain is a condition often seen by healthcare providers. It is presented as pain and tenderness under the heel with weight bearing activities. Approximately 15% of athletic and non-athletic adults who have foot complaints seek professional care for plantar heel pain. There are different names and definitions for this condition in the literature such as plantar heel pain, plantar fasciitis, plantar fasciosis, plantar fasciopathy, heel spur syndrome, and jogger's heel. The reason for inconsistency in defining the condition is due to disagreement on the underlying pathology. A number of conditions may result in plantar heel pain, namely plantar fasciitis (most common), calcaneus fracture, heel fat pad atrophy, and peripheral nerve dysfunction. Recently, several studies have shown that myofascial trigger points (MTrPs) or tender points in the calf muscles may be associated with plantar heel pain. Many studies have determined risk factors in the development of plantar heel pain, classifying them as either intrinsic or extrinsic. Intrinsic risk factors comprise the anatomical (ROM of the ankle and subtalar joints position) or demographic characteristics of the individual (age, gender, weight and height). Extrinsic risk factors are related mainly to the subject's activity environment, such as running on a hard surface, time spent weight bearing, and previous injury. All these factors lead to an increase in the mechanical load on the foot, specifically the plantar fascia. Treatment of plantar heel pain usually targets the plantar fascia or other structures in the plantar heel area using several interventions such as cortisone injection, therapeutic ultrasound, laser, ice, heel pads, and night splints. Evidence varies regarding the effectiveness of these interventions.

The main aim of this study is to investigate the immediate and carry-over effects of dry cupping on calf muscle trigger points on pain and function in patients with plantar heel pain.

Inclusion Criteria:

• Unilateral plantar heel pain.
• Trigger point(s) in the gastrocnemius/soleus muscle(s).
• Central or centro-medial tenderness in the plantar aspect of the heel.

Exclusion Criteria:

• Red flags: tumor, fracture, rheumatoid arthritis, osteoporosis, or any severe vascular condition in the lower limbs.
• Neurological symptoms: sciatica, tarsal tunnel syndrome.
• Previous surgery in the affected leg below the hip.
• Fibromyalgia.
• Previous manual therapy treatment for the same condition within the past 6 months.
• History of more than three corticosteroid injections within the past year.