Plantar aponeurosis
The aponeurosis plantaris is a tendon plate (aponeurosis) in the area of the sole of the foot ( Latin planta pedis ). It is also known as a plantar fascia or plantar fascia .
Position, course, form and function
Towards the bottom of the foot, the fat pad of the sole of the foot and the skin are located under the plantar fascia. In the direction of the back of the foot, the short foot muscles, some tendons of the lower leg muscles, some ligaments and the foot skeleton lie above it.
The plantar fascia arises in the area of the heel from the underside of the calcaneus . From there, it first moves forward in the form of a median. The median is divided into five longitudinal reins ( Fasciculi longitudinales ) that diverge in a V-shape. In the area of the metatarsal heads there are transverse lines ( Fasciculi transversi ) that connect these longitudinal reins with one another. There are also a few other reins that run from the median to the outer and inner edge of the foot. A rein goes to the metatarsal tuberosity V (roughness of the 5th metatarsal). The five longitudinal reins end in the area of the plantar ligament and the joint capsules of the metatarsophalangeal joints .
The main function of the plantar fascia is to maintain the arch structure of the bony foot skeleton, like a tense arch. What is meant here is the tension of the so-called longitudinal arch in the inner edge of the foot. This is what makes it possible to cushion your body weight while running. In addition, it serves to stabilize the chambered fat pads in the sole area by tightening the surrounding septa. It also protects the muscles, tendons, nerves and blood vessels of the sole of the foot and serves the abductor hallucis , the flexor digitorum brevis and abductor digiti minimi partly as origin .
Bracing of the longitudinal vault
The longitudinal arch of the foot is maintained by ligaments, tendons of the long foot muscles and by the short foot muscles. The plantar fascia has a prominent position here because it is at a greater distance from the foot skeleton than the underlying structures. The greater distance increases the lever arms and thus the effectiveness of the longitudinal bracing of the bony foot skeleton.
Muscle boxes
Starting from the plantar fascia, partition walls (septa) pull towards the skeleton of the foot. These separate the following boxes for the plantar muscles:
- Big toe box.
- Middle box
- Little toe box
The abductor hallucis and flexor hallucis brevis muscles are located in the big toe box . In the middle box are the flexor digitorum brevis , the adductor hallucis , the Musculi lumbricales I-IV and the quadratus plantae muscle . The abductor digiti minimi muscle , the flexor digiti minimi brevis muscle and the opponens digiti minimi muscle are located in the small toe box .
Pressure chamber system of the sole of the foot
The plantar fascia is a fiber bundle that has grown together with the skin of the sole of the foot. They form chambers filled with fat that serve as pressure pads. The sole of the foot is attached to the aponeurosis similar to a mattress. This makes it immovable, which is important for a secure stand. If it were mobile, the sole of the foot would slip constantly under the foot.
Diseases
Plantar fasciitis
In the plantar fasciitis ( inflammation of the plantar fascia) is a painful irritation of the tendon plate extending from the inner side of the heel bone on the longitudinal arch up to the metatarsophalangeal joints. It manifests itself in a tenderness on the plantar tendon attachment of the heel bone as well as a radiating foot sole pain. Plantar fasciitis is usually caused by excessive stress on the soles of the feet (e.g. sport, obesity, job).
Plantar heel spur
In the area of origin of the plantar fascia on the processus medialis tuberis calcanei, inflammatory reactions can occur as a result of excessive stress at the tendon insertion. In the further course, tendon calcification often occurs in the chronically inflamed area of the tendon attachment of the plantar fascia on the heel bone . In X-ray diagnostics, this calcification of the tendon attachment on the plantar heel bone appears as an alleged heel spur : because the tendon or the plantar fascia cannot be shown in the X-ray image, only the spur-like calcification on the heel bone is visible. The so-called heel spur is therefore an X-ray diagnosis and can also be seen as an incidental finding in symptom-free patients.
literature
- Frank H. Netter: Netter's Orthopedics . Verlag Thieme, Stuttgart 2001, pp. 320–323, ISBN 3-13-123981-6 .
Individual evidence
- ↑ J. Hochschild: Understanding structures and functions . 3. Edition. tape 2 . Georg Thieme Verlag, ISBN 978-3-13-112373-2 , p. 338 .
- ↑ Michael Schünke , Erik Schulte , Udo Schumacher : Prometheus. LernAtlas der Anatomie. General anatomy and motor system . 4th edition. Thieme, Stuttgart 2014, ISBN 978-3-13-139524-5 , p. 498,500 f .
- ^ S. Cutts, N. Obi, C. Pasapula, W. Chan: Plantar fasciitis. In: Annals of the Royal College of Surgeons of England. Volume 94, number 8, November 2012, pp. 539-542, doi : 10.1308 / 003588412X13171221592456 , PMID 23131221 , PMC 3954277 (free full text) (review).
- ↑ KS Johal, SA Milner: Plantar fasciitis and the calcaneal spur: Fact or fiction? In: Foot and ankle surgery: official journal of the European Society of Foot and Ankle Surgeons. Volume 18, number 1, March 2012, pp. 39-41, doi : 10.1016 / j.fas.2011.03.003 , PMID 22326003 .