Tubercle (bone)
In the skeleton of humans and other animals, a tubercle, tuberosity or apophysis is a protrusion or eminence that serves as an attachment for skeletal muscles. The muscles attach by tendons, where the enthesis is the connective tissue between the tendon and bone.[1] A tuberosity is generally a larger tubercle.
Main tubercles
Humerus
The humerus has two tubercles, the greater tubercle and the lesser tubercle. These are situated at the proximal end of the bone, that is the end that connects with the scapula. The greater/lesser tubercule is located from the top of the acromion laterally and inferiorly.
Radius
The radius has two, the radial tuberosity and Lister's tubercle.
Ribs
On a rib, tubercle is an eminence on the back surface, at the junction between the neck and the body of the rib. It consists of an articular and a non-articular area. The lower and more medial articular area is a small oval surface for articulation with the transverse process of the lower of the two vertebrae which gives attachment to the head. The higher, non-articular area is a rough elevation which gives attachment to the ligament of the tubercle. The tubercle is much more prominent in the upper ribs than in the lower ribs.
Tibia
The most prominent tubercle of the tibia, a leg bone which is more commonly known as the shinbone or shankbone, is the tibial tuberosity. The tibial tuberosity is located on the tibia's anterior surface, distal to the medial condyle. It creates a bony prominence just below the patella, and can be easily located with the fingers. It creates an attachment point for the ligamentum patellae, or patellar ligament. Other tubercles of the tibia include the medial intercondylar tubercle, the lateral intercondylar tubercle, and Gerdy's tubercle.
Femur
A trochanter is one of up to three tubercles of the femur:
- Greater trochanter
- Lesser trochanter
- Third trochanter, which is occasionally present
Fifth metatarsal
In the fifth metatarsal bone, the most proximal part of the bone is termed the "tuberosity", and the secondary ossification center that is normally present thereon in children is termed the "apophysis".
Related diseases and conditions
Fractures
The main type of fracture affecting tubercles is avulsion fracture, by pulling the attached tendon.
Apophysitis
Apophysitis is an inflammation of a tubercle. It mainly affects growing children, with overuse of the affected tubercle.[8][9][10] Examples include:
- Osgood–Schlatter disease (apophysitis of the tibial tubercle)[8]
- Sever's disease (apophysitis of the posterior tubercle of the heel)[9][10]
- Sinding-Larsen and Johansson syndrome (apophysitis of the inferior pole of the patella)[11]
Enthesitis
Enthesitis is an anatomically close but separate condition, wherein there is inflammation of the entheses, the sites where tendons or ligaments insert into the bone.[12][13] It is associated with HLA B27 arthropathies such as ankylosing spondylitis, psoriatic arthritis, and reactive arthritis.[14][15]
References
- "enthesis". Medcyclopaedia. GE. Archived from the original on 2012-02-05.
- Bica D, Sprouse RA, Armen J (February 2016). "Diagnosis and Management of Common Foot Fractures". American Family Physician. 93 (3): 183–91. PMID 26926612.
- "5th Metatarsal". Emergency Care Institute, New South Wales. 2017-09-19.
- "Toe and Forefoot Fractures". OrthoInfo - AAOS. June 2016. Archived from the original on 16 October 2017. Retrieved 15 October 2017.
- Silbergleit R. "Foot Fracture". Medscape.com. Retrieved 19 October 2011.
- Deniz G, Kose O, Guneri B, Duygun F (May 2014). "Traction apophysitis of the fifth metatarsal base in a child: Iselin's disease". BMJ Case Reports. 2014 (may14 4): bcr2014204687. doi:10.1136/bcr-2014-204687. PMC 4025211. PMID 24832713.
- Nwawka OK, Hayashi D, Diaz LE, Goud AR, Arndt WF, Roemer FW, et al. (October 2013). "Sesamoids and accessory ossicles of the foot: anatomical variability and related pathology". Insights into Imaging. 4 (5): 581–93. doi:10.1007/s13244-013-0277-1. PMC 3781258. PMID 24006205.
- "OrthoKids - Osgood-Schlatter's Disease".
- "Sever's Disease". Kidshealth.org. Retrieved 2014-04-29.
- Hendrix CL (2005). "Calcaneal apophysitis (Sever disease)". Clinics in Podiatric Medicine and Surgery. 22 (1): 55–62, vi. doi:10.1016/j.cpm.2004.08.011. PMID 15555843.
- "Sinding-Larsen-Johansson Syndrome - Knee & Sports - Orthobullets". www.orthobullets.com. Retrieved 2019-08-05.
- Maria Antonietta D'Agostino, MD; Ignazio Olivieri, MD (June 2006). "Enthesitis". Best Practice & Research Clinical Rheumatology. Clinical Rheumatology. 20 (3): 473–86. doi:10.1016/j.berh.2006.03.007. PMID 16777577.
- The Free Dictionary (2009). "Enthesitis". Retrieved 2010-11-27.
- Schett, G; Lories, RJ; D'Agostino, MA; Elewaut, D; Kirkham, B; Soriano, ER; McGonagle, D (November 2017). "Enthesitis: from pathophysiology to treatment". Nature Reviews Rheumatology (Review). 13 (12): 731–41. doi:10.1038/nrrheum.2017.188. PMID 29158573. S2CID 24724763.
- Schmitt, SK (June 2017). "Reactive Arthritis". Infectious Disease Clinics of North America (Review). 31 (2): 265–77. doi:10.1016/j.idc.2017.01.002. PMID 28292540.