- Kevin deWeber, MD, FAAFP, FACSM
Kevin deWeber, MD, FAAFP, FACSM
- Family Medicine of SW Washington Residency
- PeaceHealth SW Medical Center
- Affiliate Associate Professor of Family Medicine
- Oregon Health and Science University
- Clinical Instructor of Family Medicine
- University of Washington School of Medicine
- Section Editors
- Patrice Eiff, MD
Patrice Eiff, MD
- Section Editor — Adult Orthopedics; Sports-Related Injuries
- Professor of Family Medicine
- Oregon Health & Science University
- Chad A Asplund, MD, FACSM, MPH
Chad A Asplund, MD, FACSM, MPH
- Associate Professor of Health and Kinesiology
- Director of Athletic Medicine
- Head Team Physician
- Georgia Southern University
The capitate is a major bone of the wrist that may be injured during falls onto an outstretched hand or from other trauma. This topic will review the presentation, diagnosis, and non-operative management of capitate fractures. General overviews of wrist pain and carpal fractures, as well as topics devoted to other specific carpal fractures in adults, are discussed separately. (See "Evaluation of the adult with acute wrist pain" and "Evaluation of the adult with subacute or chronic wrist pain" and "Overview of carpal fractures" and "Scaphoid fractures" and "Hamate fractures" and "Lunate fractures" and "Trapezoid fractures".)
Hand fractures are among the most common of the extremity injuries, accounting for approximately 18 percent of all fractures. Carpal bone fractures comprise between 8 and 19 percent of hand fractures . Fractures to the bones of the distal carpal row (trapezium, trapezoid, capitate, and hamate) are less frequent than fractures of bones in the proximal row (scaphoid, lunate, triquetrum, and pisiform). Capitate fractures account for approximately three percent of all carpal fractures, based primarily on large series in which computed tomography was used for definitive diagnosis [1-4].
The capitate is the largest carpal bone. Distally, it articulates primarily with the base of the third metacarpal and a small portion of the fourth; radially with the trapezoid; proximally with the scaphoid and lunate; and on its ulnar side with the hamate (image 1 and figure 1 and figure 2 and figure 3). The capitate resembles the scaphoid in that its blood supply at the proximal pole is provided by vessels coursing distal to proximal, possibly increasing the risk of fracture complications from interruption of the blood supply. The anatomy of the wrist is reviewed in detail separately. (See "Anatomy and basic biomechanics of the wrist".)
MECHANISM OF INJURY
Capitate fractures occur from a number of mechanisms. Falls onto an outstretched hand and motor vehicle crashes are most commonly cited. Cadaver studies suggest that an injury sustained with the wrist in marked extension and radial deviation can cause the dorsal lip of the distal radius to contact the scaphoid, causing a fracture at its waist, and transmitting force to the capitate, which can fracture at its neck [5-7]. The following image depicts this relatively complex mechanism of injury (figure 4). Excessive palmar flexion during trauma may also predispose the capitate to injury . Isolated fractures can occur from a dorsal blow or crush injury. Of note, injuries sustained from excessive palmar or dorsiflexion under a load (eg, falling onto an outstretched hand) may also cause dislocations or fracture dislocations involving additional carpal bones (eg, scaphoid). (See "Scaphoid fractures".)
Isolated capitate fracture is uncommon; concomitant carpal or metacarpal fractures and/or dislocations are much more common. In the largest series reported (53 capitate fractures), only 20 percent of capitate fractures were isolated . The most common injury pattern reported is a "scaphocapitate syndrome." This hyperextension injury involves a force exerted by the radial styloid that causes fractures of both the scaphoid waist and proximal capitate. Depending upon the force, this injury may result in perilunate dislocation, as well as a rotation of the capitate's proximal fracture fragment . Other concomitant injuries can include fractures of the distal radius, hamate, metacarpal, or triquetrum most commonly; and the distal ulna, trapezoid, trapezium, lunate, pisiform, or phalanges less commonly . (See "Evaluation of the adult with acute wrist pain", section on 'Perilunate and lunate dislocations'.)
- van Onselen EB, Karim RB, Hage JJ, Ritt MJ. Prevalence and distribution of hand fractures. J Hand Surg Br 2003; 28:491.
- Welling RD, Jacobson JA, Jamadar DA, et al. MDCT and radiography of wrist fractures: radiographic sensitivity and fracture patterns. AJR Am J Roentgenol 2008; 190:10.
- Balci A, Basara I, Çekdemir EY, et al. Wrist fractures: sensitivity of radiography, prevalence, and patterns in MDCT. Emerg Radiol 2015; 22:251.
- Hey HW, Chong AK, Murphy D. Prevalence of carpal fracture in Singapore. J Hand Surg Am 2011; 36:278.
- Geissler WB, Slade JF. Fractures of the carpal bones. In: Green's Operative Hand Surgery, 6th ed, Wolfe SW, Hotchkiss RN, Pederson WC, Kozin SH. (Eds), Churchill Livingstone, Philadelphia 2011.
- Stein F, Siegel MW. Naviculocapitate fracture syndrome. A case report: new thoughts on the mechansim of injury. J Bone Joint Surg Am 1969; 51:391.
- El-Khoury GY, Usta HY, Blair WF. Naviculocapitate fracture-dislocation. AJR Am J Roentgenol 1982; 139:385.
- Volk AG, Schnall SB, Merkle P, Stevanovic M. Unusual capitate fracture: a case report. J Hand Surg Am 1995; 20:581.
- Kadar A, Morsy M, Sur YJ, et al. Capitate Fractures: A Review of 53 Patients. J Hand Surg Am 2016; 41:e359.
- Gaebler C, McQueen MM. Carpus fractures and dislocations. In: Rockwood and Green's Fractures in Adults, 7th ed, Bucholz RW, Heckman JD, Court-Brown CM, Tornetta P. (Eds), Lippincott, Williams, & Wilkins, Philadelphia 2010.
- Obdeijn MC, van der Vlies CH, van Rijn RR. Capitate and hamate fracture in a child: the value of MRI imaging. Emerg Radiol 2010; 17:157.
- Sawardeker PJ, Baratz ME. Carpal injuries. In: DeLee & Drez's Orthopaedic Sports Medicine: Principles and Practice, 4th ed, Miller MD, Thompson SR. (Eds), Elsevier Saunders, Philadelphia 2015. p.861.
- Vander Grend R, Dell PC, Glowczewskie F, et al. Intraosseous blood supply of the capitate and its correlation with aseptic necrosis. J Hand Surg Am 1984; 9:677.
- Rand JA, Linscheid RL, Dobyns JH. Capitate fractures: a long-term follow-up. Clin Orthop Relat Res 1982; :209.
- CLINICAL ANATOMY
- MECHANISM OF INJURY
- SYMPTOMS AND EXAMINATION FINDINGS
- DIAGNOSTIC IMAGING
- DIFFERENTIAL DIAGNOSIS
- Fracture of the scaphoid, trapezoid or other carpal bones
- Fractures of the third metacarpal
- Scapholunate ligament sprain and instability
- Distal radius fracture
- Wrist sprain
- INDICATIONS FOR SURGICAL REFERRAL
- INITIAL TREATMENT
- FOLLOW-UP CARE
- RECOMMENDATIONS FOR RETURN TO SPORT OR WORK
- SUMMARY AND RECOMMENDATIONS