Pes anserinus (leg)
Pes anserinus ("goose foot") refers to the conjoined tendons of three muscles that insert onto the anteromedial (front and inside) surface of the proximal extremity of the tibia. The muscles are the sartorius, gracilis and semitendinosus. The name, "goose foot", arises from the three pronged manner in which the conjoined tendon inserts onto the tibia.
The three muscles are (from anterior to posterior):
The conjoined tendon lies superficial to the tibial insertion of the medial collateral ligament (MCL) of the knee.
A good mnemonic to remember the muscles which contribute tendons to this conjoined tendon and the innervations of these muscles is SGT FOT (sergeant FOT).
S- Sartorius G- Gracilis T- semiTendinosus (from anterior to posterior)
F- femoral nerve O- obturator nerve T- tibial nerve (one of the two component nerves of the sciatic nerve [the other being the common fibular (or common peroneal) nerve]. The sciatic nerve itself cannot technically innervate anything because it is merely the designation for the common sheath that encases the tibial and common fibular nerves.)
Notice the order of the muscles (S, G, T) follows the order of the innervating nerves which correspond to those muscles (F, O, T)
It is a cause of chronic knee pain and weakness ("pes anserine bursitis"). Pes bursitis is a condition in which the medial portion of the knee is inflamed. If the bursa underlying the tendons of the sartorius, gracilis, and semitendinosus gets irritated from overuse or injury a person can develop this ailment. This condition usually occurs in athletes from overuse. This pathology is characterized by pain, swelling, and tenderness.
- Mochizuki T, Akita K, Muneta T, Sato T (January 2004). "Pes anserinus: layered supportive structure on the medial side of the knee". Clin Anat 17 (1): 50–4. doi:10.1002/ca.10142. PMID 14695588.
- MedicalMnemonics.com: 3447
- pmr/104 at eMedicine - "Pes anserinus bursitis"
- Alvarez-Nemegyei J (April 2007). "Risk factors for pes anserinus tendinitis/bursitis syndrome: a case control study". J Clin Rheumatol 13 (2): 63–5. doi:10.1097/01.rhu.0000262082.84624.37. PMID 17414530.
- Zaffagnini S, Golanò P, Farinas O, et al. (January 2003). "Vascularity and neuroreceptors of the pes anserinus: anatomic study". Clin Anat 16 (1): 19–24. doi:10.1002/ca.10073. PMID 12486734.
- Pes_anserinus at the Duke University Health System's Orthopedics program
- Description at rad.washington.edu