PED Case 10: Carpal coalition

Simone Montoya, M.D.

URMC Department of Imaging

Publication Date: 20170629


Patient is an 18-year-old female with one year of right hand pain after an altercation and sustained bite injury.


Right hand radiographs revealed no fracture, dislocation, osseous or soft tissue lesion, joint abnormality, or radiopaque retained foreign body. Incidentally noted are lack of cleavage planes between the scaphoid and lunate, and capitate and hamate.


Carpal coalition


Carpal coalition is partial or complete fusion of 2 or more carpal bones. Estimated incidence is 1-2%, depending on ethnic population. The most common coalition occurs between the lunate and triquetrum, but can occur between any adjacent bones. The fusion is developmental and may be osseous (synostosis), cartilagenous (synchondrosis), or fibrous (syndesmosis). Most often carpal coalition is discovered incidentally, such as during work up for trauma. Carpal coalition is usually asymptomatic, although it has been postulated that pain may occur due to degenerative changes related to deficient articular cartilage, or due to altered mechanics. Carpal coalition usually occurs in isolation, but multiple coalitions raise suspicion for a genetic syndrome.



  1. van Hoorn BT, Pong T, van Leeuwen WF, Ring D. Carpal coalitions on radiographs: prevalence and association with ordering indication. J Hand Surg Am. 2017 May;42(5):329-334. PMID: 28284456 DOI: 10.1016/j.jhsa.2017.02.0026
  2. Tatco V, Weerakkody Y, et al. Carpal coalition. Accessed at on June 13, 2017.

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