Absence of gluteal muscle
The congenital absence of the gluteal muscle was described in 1976, as occurring in a brother and sister with absence of gluteal muscles and with spina bifida occulta. It was thought to be caused by an autosomal recessive gene.
Edgar et al. (2012) reported the case of a 15-year-old white male with congenital absence of the gluteus maximus muscles associated with spina bifida occulta, learning disability, optic nerve hypoplasia, scoliosis, and central nervous system hamartomas.
If gluteal muscles were absent the following actions would not be possible. The gluteus maximus extends the thigh at the hip in actions like stair climbing, running or walking. It also abducts the thigh, elevates the trunk and also prevents the trunk of a person from moving forward or backward when the rest of the body is in movement. The gluteal maximus also aids in stabilizing the femur and the tibia. The gluteas minimus and medius are also part of the gluteal muscles. If these muscles were missing, the leg would not be able to abduct or medial rotate the thigh. The body would also not be able to shift weight from one side to the other when one foot is on the ground but not another. Considering this a rare congenital disease with other complications, walking would also not be possible in the list of additional symptoms above.
Pathology is insertional tendinopathy of the medius and tendons and enlargement of the associated bursa. Gluteals remain inactive in a seated position. Movements that require muscles become more difficult; stress is put on the spine.
- Carnevale A, del Castillo V, Sotillo AG, Larrondo J (1976). "Congenital absence of gluteal muscles. Report of two sibs". Clin Genet. 10 (3): 135–8. PMID 786514. doi:10.1111/j.1399-0004.1976.tb00025.x.
- Edgar, E. M., Carlson, H. L., Egan, R. A., Riccelli, L. P., Cupler, E. J. Congenital absence of gluteal muscles, optic nerve hypoplasia, and central nervous system hamartomas. Clin. Dysmorph. 21: 106-108, 2012. [PubMed: 22146147, related citations] [Full Text: Lippincott Williams & Wilkins]
- Saladin, Keneth (2012). Anatomy and Physiology: The Unity of Form and Function. New York, NY: McGraw Hill. p. 526. ISBN 978-0-07-337825-1.