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anatomic-based examination of the hand andwrist, allowing the physician to quickly evalu-ate a patient in a nonemergent setting. Parttwo2 focuses on the emergent evaluation ofhand and wrist injuries.

Anatomy

Many injuries of the hand and wrist are obvi-

ous, but subtle injuries can be missed withouta systematic primary and secondary examina-tion. There are eight carpal bones in the wrist,five metacarpals, and 14 nonsesamoid bonesthat comprise the phalanges. These 27 bonesact dynamically to allow oppositional grip.3The proximal row of carpal bones includes thescaphoid (i.e., carpal navicular bone), lunate,triquetrum, and pisiform, which are closelyapproximated to the distal radius (Figure 1).The triangular fibrocartilage complex, an artic-ular disk located between the proximal row of

carpals and the ulna, completes the concavesurface on which the carpals move (Figure 2).The distal row of carpals includes the hamate,capitate, trapezium, and trapezoid, which areclosely approximated to the metacarpals. Thescaphoid links the two rows of carpals.

Each digit has two neurovascular bundlesnear the palmar aspect of the fingeronelocated radially and the other ulnarly. Theneurovascular bundle includes the digitalartery, vein, and nerve.4

Twelve extensor tendons of the wrist are

Whether a physician isworking in a rural clinicor an urban academiccenter, or is attendinga high school football

game, acute injuries of the hand and wrist willbe encountered. Patients may not appreciatethe severity of these injuries and are as likely

to present in a clinic as in the emergencydepartment. Timely diagnosis and treatmentof upper extremity injuries are of paramountimportance. Failure to diagnose, manage, andrehabilitate upper extremity injuries has thepotential to result in permanent disability.1

Part one of this two-part article reviews an

Diagnosis of upper extremity injuries depends on knowledge of basic anatomy and bio-

mechanics of the hand and wrist. The wrist is composed of two rows of carpal bones.

Flexor and extensor tendons cross the wrist to allow function of the hand and digits.

The ulnar, median, and radial nerves provide innervation of the hand and wrist. A sys-

tematic primary and secondary examination of the hand and wrist includes assessment

of active and passive range of motion of the wrist and digits, and dynamic stability

testing. The most commonly fractured bone of the wrist is the scaphoid, and the most

common ligamentous instability involves the scaphoid and lunate. (Am Fam Physician

2004;69:1941-8. Copyright 2004 American Academy of Family Physicians.)

Hand and Wrist Injuries:Part I. Nonemergent EvaluationJAMES M. DANIELS II, M.D., M.P.H., Southern Illinois University School of Medicine, Quincy, IllinoisELVIN G. ZOOK, M.D., Southern Illinois University School of Medicine, Springfield, IllinoisJAMES M. LYNCH, M.D., Florida Southern College, Lakeland, Florida

This is part I of a

two-part article on

hand injuries. Part II,

Emergent Evaluation,

appears in this issue

on page 1949 (Am

Fam Physician 2004;

69:1949-56).

FIGURE 1. The bones of the wrist.

Trapezoid

Capitate

Hamate

Distal carpal row

Proximal carpal row

Pisiform

Triquetrum

Trapezium

Scaphoid

Lunate

Radius

Ulna

ILLUSTRATIONSBYSCOTBODELL

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arranged in six compartments along the dor-sum of the wrist. There are multiple slips ofthe abductor pollicis longus and two slips ofthe extensor digiti quinti. The extensors origi-nate in the lateral and dorsal forearm, insert-ing on the dorsal aspect of the hand. Twelveflexor tendons of the wrist originate in themedial part of the forearm and insert on thepalmar aspect of the hand and wrist.5

Each phalanx has a superficial flexor tendon

that inserts at the base of the middle phalanxand a profundus flexor tendon that inserts atthe base of the distal phalanx. Consequently,injuries of the flexor tendons are more com-plicated to evaluate and repair than injuries ofthe extensor tendons.

The extrinsic extensor tendon attaches tothe base of the dorsum of the middle phalanx,and bands from the intrinsic hand musclesattach to the distal phalanx. The tendons are

connected by fibers that form a hood over theproximal interphalangeal (IP) joint6 (Figure3).

In general, the radial nerve accounts for wristand finger extension, the ulnar nerve providespower grip, the median nerve allows for finecontrol of the pincer grip, and the median andulnar nerves supply sensation to the palmarsurface. However, to truly place the hand in afunctioning position, the entire upper extrem-ity must be involved. The ulnar nerve enters

the hand alongside the ulnar artery through

1942-AMERICAN FAMILY PHYSICIAN www.aafp.org/afp VOLUME 69, NUMBER 8 / APRIL 15, 2004

FIGURE 3. The tendons of the finger.

Extensor tendon

Flexor digitorumprofundus tendon

Flexor digitorumsuperficialis tendon

FIGURE 2. The dorsum of the hand.

Extensor indicis tendon

Distal phalanx

Middle phalanx

Proximalphalanx

Extensordigitorumtendons

Extensor digitiminimi tendon

Extensordigitorumcommonis

Extensorpollicislongustendon

Anatomicalsnuff-box

Ulna

Radius

Extensorindicistendon

Extensordigitorumcommonistendons

Extensordigiti minimitendon

Triquetrum

Triangularfibrocartilagecomplex

UlnaRadius

Listers tubercle

Scaphoid

Lunate


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Guyons canal, located between the pisiformand the hook of the hamate and covered bythe pisohamate ligament (Figure 4). The ulnarnerve supplies the intrinsic muscles of thehand as well as the extrinsic muscles for flex-ion of the fourth and fifth fingers to providepower grip. The ulnar nerve also innervates the

adductor pollicis and first dorsal interosseousmuscles, which allow pinch. The median nervepasses into the hand via the carpal tunnel ofthe volar aspect of the wrist. The median nervesupplies the thenar compartment, providing

opposition and circumduction for fine con-trol. The radial nerve extends the fingers toenhance grasp with the ulnar nerve.

Examination

An efficient method for evaluating the handis to begin with a primary survey, then per-

form a secondary survey. Summaries of eachexamination are given in Tables 1 and 2.

PRIMARYEXAMINATION

The primary survey includes evaluation

APRIL 15, 2004 / VOLUME 69, NUMBER 8 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN-1943

TABLE 1

Primary Physical Examination of the Hand and Wrist

Examination technique Abnormal result Possible pathology

While the patients hand is in the resting position Flexed finger Disrupted extensor tendon (see Figure 6

right)

look for fingers that are flexed or extended Extended finger Disrupted flexor tendon (see Figure 6 left)

While patient flexes fingers toward the palm, Fingers extend normally but Fracture with rotational

check that tips of fingers point toward the overlap when flexed deformity of finger

scaphoid (see Figure 7)

Check for changes in skin color or ability to sweat Part or all of finger has a different Digital nerve injury

skin color (blanched or hyperemic)

or lacks ability to sweat

Check capillary refill after applying pressure to Blanching lasts more than two Microvascular compromise

distal fingertip or nail bed seconds

Check two-point discrimination in distal fingertip Patient cannot distinguish two Neurologic compromise

using blunt calipers or a paper clip points at least 5 mm apart

FIGURE 4. The palm of the hand.

Distal interphalangeal joint

Flexor carpiulnaris tendon

Palmaris longus tendon

Thenar eminence

Flexor carpiradialis tendon

Distal interphalangeal joint

Distal transversepalm crease

Proximalinterphalangeal

joint

Base ofproximalphalanx

Transversecarpal ligament

Radiallongitudinalpalm crease

Proximaltransversepalm crease

Flexor retinaculum

Hook ofhamate

Pisohamate ligament(roof of Guyons canal)

PisiformTuberosityof scaphoid

Radiallongitudinalpalm crease

Proximaltransversepalm crease

Distal transversepalm crease

Proximalinterphalangeal

joint

Base ofproximalphalanx


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of passive and active range of motion of thefingers and wrist while noting the resting posi-tion of the hand. Manipulation is not alwaysnecessary; much can be noted about the handand fingers with simple observation.

A patients inability to assume the safe

hand position (Figure 5) may suggest atendon or nerve disruption.7 If the hand isimmobilized in the safe hand position, exten-sion contractures of the metacarpophalangeal(MCP) joint and flexion contractures of the

IP joints can be avoided. In normal anatomicposition, the thumb is slightly abducted, theMCP joint is at 45 to 70 degrees, and each ofthe IP joints is slightly flexed at 10 degrees.Physicians should be alerted to the possibil-


TABLE 2

Secondary Physical Examination of the Hand and Wrist

Examination technique Abnormal result Possible pathology

The patient flexes the proximal IP joint of the affected Patient cannot flex joint Disrupted flexor digitorum

finger while the other fingers are kept extended. superficialis

The patient extends the distal IP joint of the affected Patient cannot flex joint Disrupted flexor digitorum

finger while the other fingers are kept extended. profundus (i.e., jersey finger)

The patient extends the distal IP joint of the affected Patient cannot extend joint Fracture of distal phalanx or rupture offinger. or lacks complete joint extensor tendon (i.e., mallet finger)

extension

The patient shakes hands with the examiner, then Patient has pain or cannot Pathology of distal ulnar joint or

attempts to pronate and supinate the wrist while complete the movement triangular fibrocartilage complex

the examiner resists movement. (in the absence of radiographic findings)

Locate the small, bony prominence on the ulnar aspect Tenderness Trauma to pisiform

of the palm in the area of the palmar crease.

After pisiform is located, the physicians thumb IP joint Tenderness Fracture of hook of the hamate

is placed on the pisiform, and the thumb is directed

toward the patients index finger. When the patient

flexes the wrist, the hook of the hamate can be felt

with the tip of the thumb.

Follow the extensor carpi radialis tendon distally where it Tenderness Fracture of scaphoid tubercle

intersects the palmar crease, then palpate the small

protuberance.

Locate the extensor pollicis longus and abductor pollicis Tenderness Fracture of distal pole

longus, then palpate the depression between them

(the anatomical snuff-box).

Physicians thumb is placed on scaphoid tubercle while Pain Fractured scaphoid

thewrist is held in ulnar deviation, then the patient Pain with clunk Scapholunate instability

actively radially deviates the wrist while the physician

exerts pressure on the tubercle (see Figure 8)

Patients wrist is held in flexion while the physician Pain Parascaphoid inflammation, radiocarpal

resists active finger extension (see Figure 9) instability, midcarpal instability

IP = interphalangeal.

FIGURE 5. Normal anatomic position of the

hand (the safe hand position).

A primary survey includes evaluation of passive and active

range of motion of the fingers and wrist while noting the

resting position of the hand.


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ity of tendon disruption if any of the fingersare not maintained in the position8 (Figure6). As the hand is closed, fingers should pointtoward the base of the scaphoid (Figure 7).The distal nail tips should align when the fin-gers are partially flexed.

Subtle skin changes can alert the physicianto possible nerve injury. The hand normallyhas moisture on it; absence of moisture on

the distal phalanx may indicate a digital nerveinjury. The vascular status of the finger is eval-uated by blanching the fingertip; capillariesshould refill within two seconds. Sensory nervefunction of the digits can be evaluated withtwo-point discrimination using a paper clipor blunt calipers. The patient should be able todistinguish two points about 5 mm apart.3

SECONDARYEXAMINATION

The secondary survey should include tests ofthe superficialis and profundus flexor tendon

of each finger.1 With practice, each of the flexortendons of the fingers can be evaluated. Eachdigit should flex independently. The patientshould be able to actively flex the distal IP joint,indicating an intact profundus flexor tendon.The superficialis tendon is evaluated by havingthe patient flex the proximal joint of the fingerwhile the remaining fingers are extended. Ifthere is any question of tendon disruption, asimple test can be performed. In this test, thephysician grasps the patients forearm approxi-

mately 6 to 7 cm from the proximal palmar

crease of the wrist and squeezes the forearm.9As the forearm is grasped, each of the flexortendons can be identified by passive flexionof the patients corresponding digit. Range ofmotion of the wrist, as well as any deformity orswelling, should be noted. Full forced prona-tion and supination of the hand without painvirtually eliminates pathology of the distalradioulnar joint or triangular fibrocartilage

complex from consideration.10Palpation of the hand usually starts on the

ulnar side. The pisiform can be palpated easilyin the hypothenar eminence just distal to thedistal wrist crease on the palmar ulnar aspectof the hand. To locate the hook of the hamate,the physician places his or her thumbs IP joint

Hand Injuries


FIGURE 6. Signs of tendon injuries. (Left) Flexor tendon disruption. (Right) Extensor tendondisruption.

FIGURE 7. Approximate location of the scaph-oid bone. In the flexed position, all fingers

should point to the scaphoid.


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on the patients pisiform and directs the distalaspect of his or her thumb toward the patientsindex finger. When the patients wrist is flexed,the hook of the hamate can be felt with thetip of the physicians thumb. A fracture of thehook of the hamate usually is not apparenton typical radiographic images of the hand; acarpal tunnel view or computed tomographicscan sometimes is necessary.11

The flexor carpi ulnaris, the flexor carpiradialis, and the palmaris longus tendonsusually can be observed by having the patientoppose the thumb and fifth finger while flex-ing the wrist. The flexor carpi ulnaris insertson the pisiform. Because 12 to 15 percent ofpeople lack a palmaris longus tendon, caremust be taken not to confuse the flexor carpi

radialis for the missing tendon. The flexorcarpi radialis can be seen distally on the volarradial aspect of the wrist as it crosses the dis-tal palmar crease. In this area, the proximaltubercle of the scaphoid is a prominence thatcan be palpated easily. If the thumb is placedon the scaphoid tubercle, four fingers canwrap around the distal radius while the wrist isheld in ulnar deviation. As the patient radiallydeviates the wrist, the scaphoid tubercle willvolarflex into the physicians thumb. If pres-sure is directed dorsally with the thumb, painmay be elicited. This reaction may indicate afractured scaphoid, or a scapholunate insta-bility if an associated clunk is noted. Thismaneuver is termed the Watson or ScaphoidShift Test12(Figure 8).

On the dorsum of the wrist, the anatomi-cal snuff-box can be identified easily as thepatient abducts and extends the thumb. Theextensor pollicis longus tendon can be iden-tified on the radial aspect of the wrist byhaving the patient raise the thumb with the

palm pronated on a surface. The waist of thescaphoid is located just radial in a depressionin the wrist. Pain in this area can be an indi-cation of a scaphoid fracture.13 The patientswrist is then held in flexion, and active fingerextension with resistance is tested. Significantparascaphoid inflammation, radial carpal, ormidcarpal instability will cause considerablepain with this maneuver, known as the ShuckTest1(Figure 9).

The triscaphe joint is located by followingthe dorsal side of the second finger proxi-

mally; the physicians thumb will fall into arecess. The scapholunate joint can be palpatedby following the third finger proximally untilthe thumb falls into a recess, just distal toListers tubercle dorsally. Listers tubercle is asmall, mast-like protuberance in the center ofthe distal radius that is identified by palpatingthe distal radius while the patient flexes thewrist. The lunate is the most prominent areaon the dorsum of a flexed wrist. Kienbcksdisease, a post-traumatic avascular necrosis

of the lunate, is present in up to 20 percent of


Patients with pain over the anatomical snuff-box should be

treated for a possible scaphoid fracture.

The Authors

JAMES M. DANIELS II, M.D., M.P.H., is associate professor of family and communitymedicine and director of the Primary Care Sports Medicine Fellowship Program atSouthern Illinois University School of Medicine in Quincy, where he received his medi-cal degree and completed residency training at the Quincy Family Practice ResidencyProgram. Dr. Daniels completed postgraduate training in occupational medicine at theUniversity of California, San Francisco, School of Medicine, and received a mastersdegree in public health from the Medical College of Wisconsin, Milwaukee. He holdsadded qualifications in primary care sports medicine and preventive medicine.

ELVIN G. ZOOK, M.D., is professor, chairman, and founder of the Department of Plasticand Reconstructive Surgery at Southern Illinois University School of Medicine in Spring-field. He received his medical degree from Indiana University School of Medicine, India-

napolis, where he also completed a plastic surgery residency. Dr. Zook completed handsurgery fellowships at the Indiana University School of Medicine and the University ofLouisville (Ky.) School of Medicine, and holds an added qualification in hand surgery.

JAMES M. LYNCH, M.D., is assistant professor in the athletic training education pro-gram at Florida Southern College, Lakeland. He received his medical degree from theUniversity of Missouri School of Medicine, Columbia, and was chief resident at theUniversity of Kentucky Family Practice Residency Program in Lexington. Dr. Lynch alsocompleted a primary care sports medicine fellowship at the American Sports MedicineInstitute in Birmingham, Ala.

Address correspondence to James M. Daniels II, M.D., M.P.H., Southern Illinois Uni-versity School of Medicine, Primary Care Sports Medicine Fellowship, Quincy FamilyPractice Center, 612 N. 11th St., Suite B, Quincy, IL 62301 (e-mail: [email protected]). Reprints are not available from the authors.


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patients with lunate fractures.

PathologyUnderstanding the surface anatomy of the

hand and wrist allows the physician to evalu-ate common injuries and appreciate less com-mon injuries that might be overlooked onexamination.

The scaphoid is the most commonly frac-tured bone of the wrist. Most of these frac-tures are caused by falling on an outstretchedhand. Depending on the patients age, bonedensity, and reaction time, this type of fall can

result in a fractured scaphoid, scapholunate

dislocation, or distal radius fracture.14Patients with pain over the anatomical

snuff-box should be treated for a possible

scaphoid fracture, and a radiograph in whatis called the stretch or navicular view shouldbe obtained. This type of fracture carries ahigh likelihood of nonunion. To prevent supi-nation and pronation of the wrist, the patientshould be put into a long arm cast, or a shortarm thumb spica splint or cast and shouldersling; a simple palmar splint or sugar-tongsplint is inadequate.

Patients with negative radiographs shouldbe put into a temporary thumb spica splint

for two weeks. When they are reexamined,

Hand Injuries


FIGURE 8. The Watson or Scaphoid Shift Test. (Left) The physicians thumb is placed on the scaph-oid tubercle while the patients wrist is in ulnar deviation. Pressure is applied dorsally. (Right)The patient radially deviates the wrist. Great pain indicates ligamentous instability of the wristbetween the scaphoid and the lunate.

FIGURE 9. The Shuck Test for perilunate instability. (Left) The wrist is held in flexion by the phy-sician, and the patient extends his or her fingers. (Right) The physician resists this movement.Significant parascaphoid inflammation, radial carpal, or midcarpal instability may cause consid-erable pain with this maneuver.


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another radiograph should be taken. If thepatients wrist is not tender and the secondradiograph is negative, the patient can beinstructed to return only if symptoms recur. Ifthe wrist is still tender, further evaluation anda surgical consultation are warranted even ifthe second radiograph is negative.15

A fractured hook of the hamate is a lesscommon injury of the wrist that often isnot diagnosed because it is not apparenton standard radiographic views. This injurymay occur when a patient falls while holdingan object, and the object lands between theground and the ulnar side of the palm. It alsomay be caused when a bat hits a ball or a golfclub catches the ground, and the hypothenar

eminence is struck. Standard radiographs anda carpal tunnel view should be obtained inpatients with tenderness over the hook of thehamate, and the ulnar nerve should be tested.These patients can be put in an ulnar guttersplint or simple volar splint and referred toa surgeon, because treatment often requiresremoval of a bone chip.10

The most common ligamentous instabil-ity of the wrist occurs between the scaphoidand the lunate. Patients with injuries of theseligaments often have a high degree of pain

even though initial radiographs may appearnormal. A gap of more than 3 mm in thescapholunate joint is considered abnormal,and a comparison radiograph of the oppositewrist should be obtained. Physicians shouldsuspect this type of injury if a patient haswrist effusion and pain that is seemingly outof proportion to the injury. Patients with thistype of injury often will not tolerate a Watson

test. These injuries require an immediate con-sultation but can be stabilized with a thumbspica splint.16

Figures 2 (left), 4 (left), and 5 through 9 reprinted

with permission from the authors.

The authors indicate that they do not have any

conflicts of interest. Sources of funding: none

reported.

REFERENCES

1. Werner SL, Plancher KD. Biomechanics of wrist

injuries in sports. Clin Sports Med 1998;17:407-20.2. Daniels JM 2d, Zook EG, Lynch JM. Hand and wrist

injuries: Part II. Emergent Evaluation. Am Fam Phy-sician 2004;69:1949-56.

3. American Society for Surgery of the Hand. Historyand general examination. In: The hand, examina-tion and diagnosis. 2d ed. N.Y.: Churchill Living-stone, 1983:3-10.

4. Moore KL. The upper limbthe hand. In: Clinicallyoriented anatomy. Baltimore: Williams & Wilkins,1980:786-809.

5. Lampe EW. Surgical anatomy of the hand with spe-cial reference to infections and trauma. Clin Symp1969;21:66-109.

6. Perron AD, Brady WJ, Keats TE, Hersh RE. Ortho-

pedic pitfalls in the emergency department: closedtendon injuries of the hand. Am J Emerg Med2001;19:76-80.

7. American Society for Surgery of the Hand. Thephysical examination. In: The hand: primary careof common problems. New York: Churchill Living-stone, 1985:3-7.

8. Blair WF, Steyers CM. Extensor tendon injuries.Orthop Clin North Am 1992;23:141-8.

9. Dolphin JA. Evaluation of a laceration in the handor wrist. J Trauma 1983;23:263.

10. Morgan WJ, Slowman LS. Acute hand and wristinjuries in athletes: evaluation and management.J Am Acad Orthop Surg 2001;9:389-400.

11. Greenspan A. Upper limb IIdistal forearm, wristand hand. In: Orthopedic radiology: a practicalapproach. 3d ed. Philadelphia: Lippincott Williams& Wilkins, 2000:175-6.

12. Lewis DM, Osterman AL. Scapholunate instabilityin athletes. Clin Sports Med 2001;20:131-40.

13. Hodgkinson DW, Kurdy N, Nicholson DA, DriscollPA. ABC of emergency radiology. The wrist. BMJ1994;308:464-8.

14. Schaffer TC. Common hand fractures in familypractice. Arch Fam Med 1994;3:982-7.

15. Resnik CS. Wrist and hand injuries. Semin Muscu-loskelet Radiol 2000;4:193-204.


A gap of more than 3 mm in the scapholunate joint in a

symptomatic patient should alert the physician to consider

scapholunate instability until proven otherwise.

Hand Injuries

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