Jialiang Guo, Lei Liu, and Chenni Ji

A total of 144 patients with 145 hand fractures were investigated in the China National Fracture Study (CNFS). The fractures accounted for 8.17% of all patients with fractures and 7.91% of all types of fractures. The population-weighted incidence rate of pelvic ring and acetabular fractures was 27 per 100,000 population.

The epidemiologic features of hand fractures in the CNFS are as follows:

• More males than females

• More right-side injuries than left-side injuries

• The highest risk age group is 15–64 years

• The phalanx fracture is the most common hand fractures

• Injuries occurred most commonly via falls and crushing injury

Hand Fractures by Injury Side in CNFS

A total of 62,555 patients with 63,730 hand fractures were treated in 83 hospitals of China over a 2-year period from 2010 to 2011. All cases were reviewed and statistically studied; the fractures accounted for 15.08% of all fractured patients and 14.76% of all types of fractures. Among these 62,555 patients, there were 4,847 children with 4,881 hand fractures, accounting for 8.87% of pediatric patients with fractures, and 8.50% of all types of fractures in children. The rest of the 57,708 adult patients had 58,849 fractures, representing 16.02% of adult patients with fractures, and 15.72% of all types of fractures in adults.

Epidemiologic features of hand fractures are as follows:

• More males than females

• More right-side than left-side injuries

• The high-risk age group is 21–25 years, the same age group for males whereas the high-risk age group for females is 36–40 years

• Phalanx fractures are the most common fractures of the hand

Hand Fractures by Fracture Side

Hand Fractures by Locations in Adults Based on OTA Classification

Hand Fractures by Locations in Children

There are eight carpal bones, arranged in two rows. Those of the proximal row, from lateral to medial, are scaphoid, lunate, triangular, and pisiform; those of the distal row, in the same order, are the trapezium, trapezoid, capitate, and hamate. From the proximal row, the superior articular surface of the scaphoid, lunate, and triangular are connected by ligaments, present a convex surface, and articulate with the inferior surface of the radius and articular disk, forming the radiocarpal joint; the distal row of carpal bones articulates with the proximal bases of the five metacarpal bones, forming the carpometacarpal joints.

Carpals are short bones; each bone (except the pisiform) has six surfaces. The anterior and posterior surfaces, which have ligamentous attachment, are rough. The surfaces where the carpal bones make contact with contiguous bones are all articular, thus covered with articular cartilage, and are involved in the formation of the joint. The construction of these short bones provides complex but limited movement.

A total of 3,057 patients with 3,064 carpal fractures were treated in 83 hospitals of China over a 2-year period from 2010 to 2011. All cases were reviewed and statistically studied; the fractures accounted for 5.30% of all adult patients with fractures and 5.21% of hand fractures in adults. Their epidemiologic features are as follows:

• More males than females

• The high-risk age group is 21–25 years, the same age group for males whereas the high-risk age group for females is 56–60 years

• Scaphoid fractures (72) are the most common of carpal bone fractures (71–76)

Carpal Fractures (Segments 71–76) by Sex

Most carpal fractures are a result of axial loading on the outstretched palm and an extended wrist, for example, from a fall on an outstretched hand or motor-vehicle collision. A direct blow to the dorsum of the hand, a crush injury, or cutting through the dorsum of the hand can also cause this type of injury.

Most patients present with history of a fall on an outstretched hand, or a traumatic event like a motor-vehicle accident. If palpation of each carpal bone and the intercarpal ligaments elicit pain and apparent local tenderness, then one should strongly suspect the presence of fractures. Where carpal fracture is suspected, X-rays of AP, lateral, and oblique views are needed. Bone scans and computed tomography (CT) scans are sometimes helpful if the plain X-ray is inconclusive for fracture.

Most carpal fractures, except scaphoid, can be treated with nonsurgical intervention. The indications for nonsurgical treatment are as follows:

• Nondisplaced carpal fracture

• Stable wrist joint injury, with less than 2 mm fracture displacement

• Stable wrist joint injury, with less than 1 mm intra-articular fracture step-off

• Isolated ligamentous rupture, in elderly low-demand patients

• Hamate fracture with the hook intact

• Pisiform fracture

The treatment principle for scaphoid fractures is discussed in the next section of this chapter.

The scaphoid bone is the largest bone of the wrist bone’s proximal row. It is situated between the hand and forearm at the radial side of the carpus, and plays an important role in the formation of the radiocarpal joint. The scaphoid bone received its name from its resemblance to a boat, its long axis being from above, downward, lateralward, and forward. The dorsal surface has a rough groove, and a rounded projection called a tubercle, which is elevated at its lower and lateral part, and is directed forward; it gives attachment to the transverse carpal ligament and is sometimes the origin of a few fibers of the abductor pollicis brevis. The scaphoid has a central narrowing or waist, which is at high risk for fracture.

The proximal pole of the scaphoid is completely covered with cartilage, and receives a very limited vascular supply from a ligamentous structure (radioscapholunate ligament), in contrast to the distal two-thirds of the bone, which appears to have its own abundant blood supply. Therefore, any displaced fracture involving the proximal half of the scaphoid will severely jeopardize the vascularity of the proximal portion and may result in increased risk of avascular necrosis of that portion of the bone.

Based on AO classification, scaphoid fractures are classified into three subtypes: A, Avulsion fracture of the tubercle; B, Fracture of the waist; and C, Multiple fragments or comminuted fractures.

Russe classified scaphoid fractures as horizontal oblique, transverse, or vertical oblique, based on the direction of the fracture line.

A total of 2,101 adult patients with 2,105 scaphoid fractures were treated in 83 hospitals of China over a 2-year period from 2010 to 2011. All cases were reviewed and statistically studied, accounting for 68.73% of all adult patients with carpal fractures and 68.70% of carpal fractures in adults. Their epidemiologic features are as follows:

• The number of men greatly outweighs the number of women

• The high-risk age group is 21–25 years, the same age group for men while there is no apparent high-risk age group for women

• The waist of the scaphoid is the most frequent fracture site