[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Upper limb](https://durgical.com/en/anatomy/region/upper-limb/) › 4th metacarpal [Skeletal system](https://durgical.com/en/anatomy/system/skeletal-system/) · [Upper limb](https://durgical.com/en/anatomy/region/upper-limb/) # 4th metacarpal The fourth metacarpal is the palm bone of the ring finger; it is the thinnest metacarpal and moves slightly at the wrist. [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=upper_limb&select=metacarpal_4&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The long bone in the palm leading to the ring finger. ## What it does Forms the palm and the knuckle at its head. ## Key points - The thinnest metacarpal shaft; its carpometacarpal joint with the hamate allows some motion, so neck fractures tolerate more angulation than the index and middle but less than the little finger - A short 4th metacarpal (the knuckle sinks to a dimple in a fist) is seen in pseudohypoparathyroidism and Turner syndrome ## Key facts **Joints with** Base: capitate, hamate; head: proximal phalanx; adjacent metacarpals **Landmarks** Base, shaft, neck, head (knuckle) ## Relations **Above** [Hamate](https://durgical.com/en/anatomy/hamate/) and part of the [capitate](https://durgical.com/en/anatomy/capitate/) **Behind** [Extensor digitorum](https://durgical.com/en/anatomy/extensor-digitorum/) tendon to the ring finger, linked to its neighbours by the juncturae tendinum **Lateral** Third dorsal interosseous and second palmar interosseous **Medial** Fourth dorsal interosseous **Below** [Proximal phalanx of the ring finger](https://durgical.com/en/anatomy/proximal-phalanx-of-the-ring-finger/) ## How to find it Felt along the back of the hand between the middle and little finger rays; in a fist its head is the knuckle between those of the middle and little fingers. ## On imaging Metacarpal sign: on a PA view a line drawn along the heads of the 4th and 5th metacarpals normally passes beyond the head of the 3rd; when it cuts through the 3rd, the 4th is short. ## Clinical notes - Neck fractures of the 4th often come with a [5th metacarpal](https://durgical.com/en/anatomy/5th-metacarpal/) (boxer's) fracture from the same punch - Shaft fractures are partly splinted by the deep transverse metacarpal ligaments to the 3rd and 5th metacarpals, which limits shortening - Fracture-dislocations of the 4th and 5th carpometacarpal joints at the hamate follow a punch and are easily missed on the PA view alone ## Development Ossifies in cartilage: a primary centre appears in the shaft before birth and one secondary centre later forms at the head, not at the base as in the [1st metacarpal](https://durgical.com/en/anatomy/1st-metacarpal/). On a child's X-ray the open plate near the head shows as a dark line that can be read as a fracture. ## Related conditions - [Dupuytren contracture](https://durgical.com/en/conditions/dupuytren-contracture/) - [Boxer fracture (fifth metacarpal neck)](https://durgical.com/en/conditions/boxer-fracture/) ## Test yourself Think of the answer, then tap the question to see it. ## In which conditions is a short 4th metacarpal seen? Pseudohypoparathyroidism and Turner syndrome; the knuckle sinks to a dimple in a fist. ## What is the metacarpal sign on a PA hand X-ray? A line along the heads of the 4th and 5th metacarpals that cuts through the 3rd head means the 4th metacarpal is short. ## Which fracture often accompanies a 4th metacarpal neck fracture from a punch? A 5th metacarpal (boxer's) fracture from the same punch. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/anatomy/4th-metacarpal/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** ossa metacarpi TA2 1264 **Official Spanish (DeCS)** Hueso metacarpiano IV **English (TA2)** 4th metacarpal ## Related - [A1 pulleys](https://durgical.com/en/anatomy/a1-pulleys-of-the-flexor-tendon-sheaths/) - [CMC ligaments](https://durgical.com/en/anatomy/carpometacarpal-and-metacarpal-ligaments/) - [Dorsal interossei](https://durgical.com/en/anatomy/dorsal-interossei/) - [Extensor tendons](https://durgical.com/en/anatomy/extensor-digitorum-tendons/) - [FDP tendons](https://durgical.com/en/anatomy/flexor-digitorum-profundus-tendons/) - [Finger joint capsules](https://durgical.com/en/anatomy/finger-joint-capsules/) - [Lumbricals](https://durgical.com/en/anatomy/lumbricals/) - [Knuckle collateral ligaments](https://durgical.com/en/anatomy/collateral-ligaments-of-the-metacarpophalangeal-joints/) Sources: Terminologia Anatomica (TA2); [Anatomy, Shoulder and Upper Limb, Hand Bones](https://www.ncbi.nlm.nih.gov/books/NBK547684/); [8.5 Development of the Appendicular Skeleton](https://openstax.org/books/anatomy-and-physiology-2e/pages/8-5-development-of-the-appendicular-skeleton) (OpenStax (Rice University), 2022) · adapted, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/4th-metacarpal/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/4th-metacarpal/