Anatomical Location of the Bottom of the Foot
The bottom of the foot is anatomically referred to as the plantar surface.
Anatomical Definition
The plantar surface encompasses the entire weight-bearing undersurface of the foot, extending from the heel (calcaneus) posteriorly to the toes distally 1, 2.
This surface includes three primary contact points with the ground: the calcaneal tuberosity posteriorly, the head of the first metatarsal anteriomedially, and the head of the fifth metatarsal anterolaterally 3.
Key Anatomical Structures of the Plantar Surface
Plantar Fascia (Plantar Aponeurosis)
The plantar fascia is the major structural component of the plantar surface, originating from the calcaneus and extending distally to insert into the proximal phalanges and metatarsal heads 4, 5.
The enthesis—the anatomic location where the plantar fascia inserts into the calcaneal bone—is a common site of pathology in conditions like plantar fasciitis 6, 7.
Regional Divisions
The plantar surface can be divided into three functional areas: the heel (rearfoot), midfoot, and forefoot (ball of the foot and toes) 4.
The ball of the foot specifically refers to the plantar surface beneath the metatarsal heads, which bears significant weight during standing and gait 4.
Clinical Relevance
When examining for peripheral neuropathy in diabetic patients, loss of protective sensation is assessed on the plantar surface of the heel, metatarsal heads, arch, and tips of toes using monofilament testing 1.
Plantar ulcers in diabetic foot infections occur on this plantar surface and require assessment of depth by probing to determine involvement of deeper structures 1, 8.
The plantar surface is the primary location for conditions such as plantar fasciitis, plantar fascial tears, and heel spurs, which are best evaluated with imaging studies like ultrasound or MRI 9, 5.