Fractures of the Hand

8 Fractures of the Hand


Jialiang Guo, Lei Liu, and Chenni Ji


Overview of Hand Fractures


image Anatomic Features


The skeleton of the hand consists of 8 small carpal bones (wrist), 5 metacarpals (palm), 14 phalanges (fingers), and 2 sesamoid bones ( Fig. 8.1). The carpus is made up of eight carpal bones, which are arranged into two rows: proximal and distal rows. The proximal row from lateral to medial contains: the scaphoid, lunate, triquetral, and pisiform bones; all of these except the pisiform bone are part of the radiocarpal joint. The distal row contains, in the same order: the trapezium, trapezoid, capitate, and hamate bones, which are all involved in the formation of the carpometacarpal joints. The metacarpus consists of five cylindric bones, each of which is made up of three parts: a body, base, and head. There are 14 phalanges on each hand: 3 on each finger, and 2 on the thumb. Each finger has a proximal, middle, and distal phalange except the pollex, which has only proximal and distal phalanx.



image OTA Classification and Coding System for Hand Fractures


Based on the Orthopaedic Trauma Association (OTA) classification for fractures, a hand fracture is coded as number “7,” and the numeric codes for fractures of each individual bone are as follows: 71: lunate; 72: scaphoid; 73: capitate; 74: hamate; 75: carpal bone on the ulnar side (triquetral and pisiform bones); 76: carpal bone on the radial side (trapezium and trapezoid bones); 77: metacarpal bones; 78: phalanx bones; 79: multiple hand fractures ( Fig. 8.2).


image Epidemiologic Features of Hand Fractures in the China National Fracture Study


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



image Hand Fractures by Sex in CNFS

See Table 8.1 and Fig. 8.3.


Table 8.1 Sex distribution of 144 patients with hand fractures in the China National Fracture Study

























Sex


Number of patients


Percentage


Male


83


57.64


Female


61


42.36


Total


144


100.00



image Hand Fractures by Injury Side in CNFS

See Table 8.2 and Fig. 8.4.


Table 8.2 Injury side distribution of 144 patients with hand fractures in the China National Fracture Study





























Injured side


Number of patients


Percentage


Left


64


44.44


Right


79


54.86


Bilateral


1


0.69


Total


144


100.00



image Hand Fractures by Age in CNFS

See Table 8.3 and Fig. 8.5.



image


image Hand Fractures by Location in CNFS

See Table 8.4 and Fig. 8.6.



image


image Hand Fractures by Causal Mechanisms in CNFS

See Table 8.5 and Fig. 8.7.



image


image Clinical Epidemiologic Features of Hand Fractures


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


image Hand Fractures by Sex

See Table 8.6 and Fig. 8.8.


Table 8.6 Sex distribution of 62,555 patients with hand fractures

























Sex


Number of patients


Percentage


Male


48,799


78.01


Female


13,756


21.99


Total


62,555


100.00



image Hand Fractures by Fracture Side

See Table 8.7 and Fig. 8.9.


Table 8.7 Fracture side distribution of 62,555 patients with hand fractures





























Fracture side


Number of patients


Percentage


Left


30,291


48.42


Right


31,999


51.15


Bilateral


265


0.42


Total


62,555


100.00



image Hand Fractures by Age Group

See Table 8.8 and Fig. 8.10.



image


image Hand Fractures by Fracture Location

Hand Fractures by Locations in Adults Based on OTA Classification

See Table 8.9 and Fig. 8.11.


Table 8.9 Fracture location distribution of 58,849 hand fractures in adults

































Fracture location


Number of fractures


Percentage


71–76 (Carpals)


3,064


5.21


77 (Metacarpals)


10,145


17.24


78 (Phalanx)


33,843


57.51


79 (Multiple)


11,797


20.05


Total


58,849


100.00



Hand Fractures by Locations in Children

See Table 8.10 and Fig. 8.12.


Table 8.10 Fracture location distribution of 4,881 hand fractures in children





























Fracture location


Number of fractures


Percentage


Carpals


95


1.95


Metacarpals


884


18.11


Phalanx


3,902


79.94


Total


4,881


100.00



Carpal Fractures (Segments 71–76)


image Anatomic Features


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.


image OTA Classification of Carpal Fractures


Carpal fractures are classified based on OTA classification as follows: 71: lunate; 72: scaphoid; 73: capitate; 74: hamate; 75: ulnar carpal bones; and 76: radial carpal bones ( Fig. 8.13).



image Clinical Epidemiologic Features of Carpal Fractures (71–76)


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)


image Carpal Fractures (Segments 71–76) by Sex

See Table 8.11 and Fig. 8.14.


Table 8.11 Sex distribution of 3,057 patients with fractures of carpal bones (segments 71–76)

























Sex


Number of patients


Percentage


Male


2,284


74.71


Female


773


25.29


Total


3,057


100.00



image Carpal Fractures (Segments 71–76) by Age Group

See Table 8.12 and Fig. 8.15.



image


image Carpal Fractures (Segments 71–76) by Fracture Type

See Table 8.13, Table 8.14, Fig. 8.16, and Fig. 8.17.



image









































































71 Lunate fractures


71-A Noncomminuted


97 fractures


M: 69 (71.13%)


F: 28 (28.87%)


0.03% of total adult fractures


0.16% of adult hand fractures


3.17% of adult carpal fractures


83.62% of adult lunate fractures


71-A Anteroposterior (AP) and lateral views


image


71-B Comminuted


19 fractures


M: 13 (68.42%)


F: 6 (31.58)


0.01% of total adult fractures


0.03% of adult hand fractures


0.62% of adult carpal fractures


16.38% of adult lunate fractures


71-B


image


72 Scaphoid fractures


72-A Noncomminuted


1,838 fractures


M: 1,419 (77.20%)


F: 419 (22.80%)


0.49% of total adult fractures


3.12% of adult hand fractures


59.99% of adult carpal fractures


87.32% of adult scaphoid fractures


72-A1 Proximal pole


image


72-A2 Waist


image


72-A3 Distal pole


image


72-B Comminuted


267 fractures


M: 215 (80.52%)


F: 52 (19.48%)


0.07% of total adult fractures


0.45% of adult hand fractures


8.71% of adult carpal fractures


12.68% of adult scaphoid fractures


72-B1 Proximal pole


image


72-B2 Waist


image


72-B3 Distal pole


image


73 Capitate fractures


73-A Noncomminuted


112 fractures


M: 76 (67.86%)


F: 36 (32.14%)


0.03% of total adult fractures


0.19% of adult hand fractures


3.66% of adult carpal fractures


71.34% of adult capitate fractures


73-A AP and lateral views


image


73-B Comminuted


45 fractures


M: 28 (62.22%)


F: 17 (37.38%)


0.01% of total adult fractures


0.08% of total hand fractures


1.47% of total carpal fractures


28.66% of total capitate fractures


73-B


image


74 Hamate fractures


74-A Noncomminuted


123 fractures


M: 93 (75.61%)


F: 30 (24.39%)


0.03% of total adult fractures


0.21% of total hand fractures


4.01% of total carpal fractures


89.13% of total hamate fractures


74-A


image


74-B Comminuted


15 fractures


M: 11 (73.33%)


F: 4 (26.67%)


0.004% of total adult fractures


0.03% of total hand fractures


0.49% of total carpal fractures


10.87% of total hamate fractures


74-B


image


75 Ulnar carpal fractures (triquetrum, pisiform)


75-A Noncomminuted


312 fractures


M: 213 (68.27%)


F: 99 (31.73%)


0.08% of total adult fractures


0.53% of adult hand fractures


10.18% of adult carpal fractures


85.48% of adult ulnar carpal fractures


75-A1 Pisiform


image


75-A2 Triquetrum: AP and lateral views


image


75-B Comminuted


53 fractures


M: 34 (64.15%)


F: 19 (35.85%)


0.01% of total adult fractures


0.09% of adult hand fractures


1.73% of adult carpal fractures


14.52% of adult ulnar carpal fractures


75-B1 Pisiform


image


75-B2 Triquetrum


image


76 Radial carpal fractures (trapezium, trapezoid)


76-A Noncomminuted


145 fractures


M: 94 (64.83%)


F: 51 (35.17%)


0.04% of total adult fractures


0.25% of adult hand fractures


4.73% of adult carpal fractures


79.23% of adult radial carpal fractures


76-A1 Trapezium: AP and lateral views


image


image


76-A2 Trapezoid


image


76-B Comminuted


38 fractures


M: 25 (65.79%)


F: 13 (34.21%)


0.01% of total adult fractures


0.06% of adult hand fractures


1.24% of adult carpal fractures


20.77% of adult radial carpal fractures


76-B1 Trapezium


image


76-B2 Trapezoid


image


image Injury Mechanism


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.


image Diagnosis


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.


image Treatment


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.


Further Classification for Scaphoid Fractures


image Anatomic Features and Coding System


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.


image Clinical Epidemiologic Features of Scaphoid Fractures in Adults


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


image Scaphoid Fractures by Sex

See Table 8.15 and Fig. 8.18.


Table 8.15 Sex distribution of 2,101 patients with scaphoid fractures

























Sex


Number of patients


Percentage


Male


1,630


77.58


Female


471


22.42


Total


2,101


100.00


Mar 12, 2022 | Posted by in ORTHOPEDIC | Comments Off on Fractures of the Hand

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