Proximal phalanx, middle finger !
The proximal phalanx of the middle finger is its first bone beyond the knuckle; small hand muscles on both sides move it side to side.
Official name: Proximal phalanx of the middle finger
Opens in the Durgical app, no sign-up needed.
What it is
The proximal bone of the middle finger.
What it does
One of the finger bones; the joints between them let the finger curl.
Key facts
- Joints with
- Metacarpal head (MCP joint), next phalanx (IP joint)
- Landmarks
- Base, shaft, head (condyles)
Relations
- Above
- Head of the 3rd metacarpal at the MCP joint
- In front
- FDS and FDP tendons under the A2 pulley
- Lateral
- Second dorsal interosseous and the second lumbrical
- Medial
- Third dorsal interosseous
How to find it
The longest proximal phalanx, on the axis of the hand: the middle finger is the reference line for abduction and adduction of the other fingers, which move away from or toward it.
Examination
- Finger cascade and nail alignment with the fingers half-bent: a rotated fracture makes the middle finger overlap the index or ring finger
On imaging
PA and true lateral views of the middle finger; on the PA view the base and shaft can be hidden by the adjacent fingers unless they are spread.
Clinical notes
- Rotational malunion makes the middle finger cross a neighbour when a fist is made
- Flexor tendon adhesions over the shaft are a common cause of stiffness after these fractures, so early guarded motion is part of most treatment plans
Development
One primary centre in the shaft before birth and one secondary centre at its base; until that growth plate closes in adolescence, base fractures in children cross the physis.
Related conditions
Test yourself
Think of the answer, then tap the question to see it.
Which interossei attach to the proximal phalanx of the middle finger?
The second and third dorsal interossei, one on each side; the middle finger has no palmar interosseous.
Which pulley lies over the shaft of the proximal phalanx of the middle finger?
The A2 pulley, over the flexor digitorum superficialis and profundus tendons.
In which direction do proximal phalanx fractures of the middle finger angulate?
Apex palmar, and they can rotate, making the finger cross a neighbour in a fist if malunited.
Educational information, not medical advice. For any symptom, see a health professional.
Its names
- Official Latin (TA2)
- phalanx proximalis manus TA2 1277
- Official Spanish (DeCS)
- Falange proximal del dedo medio
- English (TA2)
- Proximal phalanx of the middle finger
Related
- Digital arteries
- A1 pulleys
- Dorsal interossei
- FDP tendons
- FDS tendons
- Finger joint capsules
- Finger pulleys
- Flexor tendon sheaths
Sources: Terminologia Anatomica (TA2); Anatomy, Shoulder and Upper Limb, Hand Bones; 8.2 Bones of the Upper Limb (OpenStax (Rice University), 2022) · adapted, CC BY 4.0; 8.5 Development of the Appendicular Skeleton (OpenStax (Rice University), 2022) · adapted, CC BY 4.0; Anatomy of the Human Body (20th ed.): Articulations of the Digits (Lea & Febiger (Gray's Anatomy, 1918), 1918) · adapted, Public domain.
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.
