clinical hand exam
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CLINICAL HAND EXAM
Authors:
Jorma Mueller, MD
Moira Davenport, MD
Bellevue Hospital Center
New York University School of Medicine
New York, NY
Medical Editor:
Aaron Hexdall, MD
OVERVIEW
The goal of this video is to review a brief, but complete, clinical evaluation of the hand in the
context of acute injury.
This video will review:
1. Inspection and Palpation of the Hand
2. Sensory Evaluation
3. Motor Evaluation
4. Evaluation of the Tendons of the Hand
5. Evaluation of the Bones of the Hand
6. Vascular Evaluation of the Hand
Prior to examining the patient, a focused history must be obtained with attention to several
important factors. First, it is important to know the patients hand dominance, which is best
assessed by asking which hand they use to write. Next, ask about the timing and mechanism of
injury. This will give you an idea of what type of injury to expect and will often help to guide the
clinical examination.
Initial clues to nervous, bony, vascular, or tendon injury are often clearly visible. One should note
obvious injuries and the positioning of the hand as this information will guide your exam. Lastly,
comparison should always be made to the other uninjured hand, if possible.
INSPECTION AND PALPATION
Now we will briefly inspect the hand prior to beginning a more targeted clinical examination.
It is noteworthy that there is some confusion as to the best way to refer to the digits. The thumb is
the first digit, the index finger the second, the middle finger the third, the ring finger the fourth,
and the pinky is the fifth. The side with the first digit is referred to as the radial aspect of the
hand, while the side with the fifth digit is referred to as the ulnar aspect. Lastly, the anterior, or
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palm side of the hand, is referred to as the volar aspect, while the posterior side of the hand is
referred to as the dorsal aspect.
In this mock patient, there is clearly asymmetry between the hands with the right hand being held
in a pathologic position.
Other changes to evaluate for:
1. Swelling, especially of the fingers or the dorsum of the hand2. Deformity, including angulation of the fingers (this may only be obvious when you ask
the patient to move their fingers)
3. Discoloration4. Obvious wounds
Palpation of the hand is part of your general exam and can help to evaluate for:
1. Masses2. Areas of tenderness3. Crepitus4. Effusions5. Vascular compromise that might manifest itself as a difference in temperature6. Foreign bodies
SENSORY EVALUATION
In this section, we will demonstrate the sensory examination of the hand. First we will start by
reviewing the anatomy and distribution of cutaneous sensation in the hand.
Lets start with the sensory distribution of the median nerve, which we see traced out on the
anterior aspect of the left palm and highlighted in green on the right hand. It travels down the
radial side of the wrist passing under the flexor retinaculum of the carpal tunnel prior to enteringthe hand.
It gives off motor branches which will be discussed in the motor exam section. The sensory fibers
of the median nerve, divide providing cutaneous sensation from the palmar aspect of the hand
extending radially from the radial one half of the fourth digit to the first digit.
On the dorsal aspect of the hand, the median nerve provides sensation to the radial half of the
fourth digit, the third, second and first digits proximal to the distal interphalangeal joint.
The ulnar nerve travels down the ulnar aspect of the forearm. Within the forearm and as it
traverses the wrist to enter the hand, it travels with the ulnar artery, so when evaluating for injury
to one, injury to the other should always be considered. It enters the palm providing cutaneoussensation to the anterior and posterior aspects of the ulnar side of the hand and to the fourth and
fifth digits. Its territory extends to the ulnar half of the fourth digit only. In this example, the
sensory distribution of the ulnar nerve is highlighted in blue.
Cutaneous sensation to the posterior and lateral aspect of the hand is provided by a superficial
branch of the radial nerve. Its path is shown here and its distribution is highlighted in red. Of
note, the radial nerve travels very superficially, dividing just prior to traversing the snuffbox
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region defined by the tendons of extensor pollicis longus and brevis. Even superficial lacerations
to this area can cause significant sensory deficit.
There are no motor branches of the radial nerve in the hand.
Please note that each finger has two radial and two ulnar digital nerves; this convention refers to
the side of the finger on which they are found, not the nerve from which they arise.
We can now discuss testing cutaneous sensation in the hand. There are a variety of ways in which
to test cutaneous sensation and care must be taken as small deficits are easy to miss.
The sensory innervation of the median nerve is best tested on the palmar aspect of the hand here.
You can begin by assessing for light touch using a cotton-tip applicator; and as always,
comparing it with the other side. If the patient cannot feel light touch, a deficit is clearly present.
Two-point discrimination is a more sensitive test of sensory innervation. The minimum distance
at which a patient can discriminate two points should be recorded on both the non-injured hand
and the area in question.
Most patients are expected to easily discriminate two points at a distance of 6mm or greater.
The ulnar nerve is classically tested on the anterior aspect of the fifth digit. Again, light touch and
two-point discrimination are useful methods to determine whether there is a deficit.
The radial nerve is classically tested in the web space between the first and second digits. Light
touch and two-point discrimination are again evaluated.
For more distal injuries, the fingers should be evaluated individually. Care should be taken to
evaluate both the radial and ulnar aspect of each digit if nerve injury is suspected.
MOTOR EVALUATION
The range of motions possible with the human hand is amazing and the muscles that must
function together are numerous. This review focuses on the basic movements of the hand and the
nerves that are responsible for activating them, rather than the names of each of the individual
muscles.
We will briefly discuss the intrinsic muscles of the hand and then the extrinsic muscles. Intrinsic
muscles are contained entirely within the hand while the extrinsic muscles are responsible for
hand motion but originate in the forearm and exert their actions through lengthy tendons.
The thenar muscles are the fleshy pad at the base of the first digit and are responsible for
abduction, opposition, and flexion of the first digit at the metacarpophalangeal joint.
The muscles responsible for these actions are innervated by the median nerve. There is another
muscle in the thenar group that merits individual attention. Adductor pollicis is contained in this
group of muscles and is responsible for adduction of the first digit.
A branch of the ulnar nerve is responsible for this action. Laceration of the ulnar nerve, or that
branch, will compromise adduction and leave the first digit in abduction.
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Here, our model demonstrates the hand position after an ulnar nerve injury.
The thenar muscles can be grossly tested by having the patient touch their first digit to the
thumbnail of their fifth digit and pulling; asking them to maintain that position while resistance is
applied. Alternatively, the hand can be laid flat on a table and the thumb brought to vertical 90
degrees against resistance.
Testing adduction of the thumb which as previously mentioned, is controlled by a branch of the
ulnar nerve, can be accomplished by having the patient hold a piece of paper or cloth in their
hand between their first and second digits. Flexion of the thumb at the IP joint indicates
compromise of the adductor pollicis and is known as Froments sign.
The hypothenar muscles are the fleshy pad at the base of the fifth digit. They are all innervated by
the ulnar nerve. They are responsible for opposition, abduction, and flexion of the fifth digit.
The hypothenar muscles can be tested simply be asking the patient to move their smallest digit
away from the hand against resistance.
Lumbricals are muscles between the flexor tendons on the palmar aspect of the hand. They areresponsible for keystroke type motionflexion at the metacarpophalangeal joints and
extension at the proximal interphalangeal joint.
The second and third are innervated by the median nerve, while the fourth and fifth are innervated
by branches of the ulnar nerve.
The interosseous muscles are contained in the palm and are responsible for abduction and
adduction of the digits.
The interosseous muscles can be tested by having the patient abduct their fingers against
resistance.
EVALUATION OF THE TENDONS OF THE HAND
The extrinsic muscles originate in the forearm and have tendons that travel into the hand by
traversing the wrist.
The tendons of the flexor digitorum profundus (FDP) pass under the flexor retinaculum and are
contained here in the carpal tunnel. They are responsible for flexion of the digits at the distal
interphalangeal joint. The tendon can be tested by placing the hand on a flat surface,
immobilizing the middle phalanx with a pen, and asking the patient to flex the finger at the distal
interphalangeal joint.
The flexor digitorum superficialis (FDS) follows the same path as the FDP tendons but runssuperficial to them, bifurcates, and inserts at the level of the middle phalanx.
It is responsible for flexion of the digit at the level of the proximal interphalangeal joint. The
tendons of the FDP pass through the bifurcated FDS to insert on the distal phalanx.
The FDS can be tested by having the patient lay their hand flat on a surface, immobilize the
proximal phalanx, and flex the fingers at the level of the proximal interphalangeal joint.
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Flexion of the first digit at the interphalangeal joint is performed by the flexor policis longus and
can be tested in a similar fashion to the flexor digitorum profundus.
Extension of the hand digits is performed by several muscles with their bodies in the forearm that
traverse the dorsal aspect of the wrist and insert onto the digits.
Extensor digiti minimi is responsible for extension of the fifth digit. It can be tested by having thepatient lie their hand flat on a surface and hyperextend the fifth digit.
The extensor digitorum tendons extend digits two through five. The hand can be laid flat again on
a surface and the tendon of each finger tested by having the patient hyperextend the digits against
resistance.
Extension of the second finger is also performed by extensor indicis, which can be tested in a
similar fashion to extensor digiti minimi.
Extension of the first digit is controlled by two muscles, extensor pollicis longus and brevis. The
path of these two tendons defines the anatomical snuffbox which contains the radial artery and
the scaphoid bone of the wrist. Extension of the thumb at the interphalangeal joint and themetacarpophalangeal joint can be tested separately against resistance.
Discussion of the complete scope of tendinous, or ligamentous injuries in the hand, is beyond the
scope of this introductory review. We will touch on a few common injuries and the tests used to
identify them.
The ulnar collateral ligament at the base of the first metacarpophalgeal joint is responsible
for stabilizing the joint in the face of radial stress. It may be disrupted with hyperextension
injuries.
To test to see if it has been disrupted, have the patient hold the hand with the first digit
completely extended and compare it to the contra-lateral side noting restriction or laxity.
Repeat the test with the digit held in 30 degrees of flexion. Increased laxity is indicative of an
injury to the ulnar collateral ligament, colloquially referred to as a Game Keepers thumb.
Stenosing tenosynovitis, also know as Trigger finger, is an inability to extend a flexed finger. It
occurs when one of the flexor tendons does not slide smoothly through the pulleys at the
metacapophalangeal joint. Patients will present with a flexed finger that must be forcibly
extended using the other hand.
Sometimes, a lump of fibrous tissue is palpable in the region of metacarpophalangeal joint when a
trigger finger is present, thus reinforcing the diagnosis.
DeQuervains tenosynovitis results from inflammation of the extensor and abductor tendons of
the first digit. It can be tested for with Finkelsteins test. The hand is positioned as shown, with
the first digit under the other four. The examiner then provides ulnar deviation at the wrist. The
Finkelsteins test is positive when it produces pain.
Swan neck deformity and Boutiniere deformity result from a breakdown in the tendinous
apparatus that runs the length of the digits. These two deformities occur most commonly post-
traumatically or in the context of advanced rheumatoid arthritis.
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The Swan neck deformity occurs when these tendons sublux dorsally resulting in hyper-
extension of the proximal interphalangeal joint with partial flexion at the distal interpahlangeal
joint.
A Boutiniere deformity is present when the central slip of the ligamentous apparatus has ruptured.
The proximal interphalangeal joint is hence held in flexion, often with the distal interphalangealjoint held in extension.
Mallet finger results from disruption of the extensor tendon insertion at the distal phalanx. Blunt
trauma or lacerations are the most common mechanisms. The finger is typically held in extension,
with flexion at the distal interphalangeal joint.
EVALUATION OF THE BONES OF THE HAND
The bony anatomy of the hand proper is relatively simple and evaluation for bony pathology, a
fracture for example, depends in large part upon the mechanism and the presence of bony
tenderness. A full discussion of the evaluation of the wrist is beyond the scope of this section, so
we will discuss the bones of the hand and wrist together.
There are eight bones in the wrist. Many clinicians find it difficult to remember them in order and
use a pneumonic device. We suggest:
Sad: Scaphoid
Lonely: Lunate
Travis: Triquetrum
Pushes: Pisiform
His: Hamate
Cart: Capitate
Through: Trapezoid
Texas: Trapezium
It is important to recognize the bones of the wrist on an A/P radiograph. Note here:
Sad: Scaphoid
Lonely: Lunate
Travis: Triquetrum
Pushes: Pisiform
His: Hamate
Cart: Capitate
Through: Trapezoid
Texas: Trapezium
Special attention should be paid to the base of the thumb, scaphoid bone and the distal radius, as
these are common sites of injury in falls on an outstretched hand.
The tubercle of the scaphoid is easily palpated on our live model. Note that it is located
approximately in the anatomic snuffbox. Tenderness with palpation of the snuffbox suggests a
scaphoid fracture, regardless of the radiographic appearance of the scaphoid.
Axial loading of the first digit is a more specific test for pathology at the carpometacarpal joint.
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There are five metacarpal bones that sit in the palm and articulate with the digits proper at the
metacarpophalangeal joints. Like the digits, they are referred to by number. The rest of the bony
structures should be palpated. Strong suspicion for fracture based on mechanism or the presence
of point tenderness on exam merits a radiograph.
Common mechanisms consistent with fractures include crush injuries and blunt trauma frompunching. Pain, edema, deformity and discoloration are common signs of fracture. The hand
should be examined in both extension and flexion, specifically evaluating for fracture associated
rotational deformities. Some proximal phalanx fractures appear normal on extension, but may be
more easily appreciated on flexion. Here, a rotational deformity of the fifth digit is simulated.
Note the asymmetry of the finger nails.
Another common injury is the fracture of the metaphysic of the fourth or fifth metacarpal, the so-
called Boxers fracture. This injury is characterized by loss of the prominence of the metacarpal
heads and tenderness.
VASCULAR EVALUATION OF THE HAND
Lets discuss the vascular supply to the hand. Looking at the anterior aspect on the radial side the
radial artery supplies the hand. From the ulnar side the ulnar artery traverses the wrist and
supplies the hand as well. Together they form superficial and deep palmar arches. Here, the deep
palmar arch is represented by dashed lines. These arches then send arterial blood to the digits.
Each finger has two radial and two ulnar digital arteries that supply it. As with the digital nerves,
the names of the digital arteries refer not to the artery from which they are derived but to which
side of the finger they are located. The arteries on the palmar aspect deliver significantly more
blood than those on the dorsal aspect.
Looking at the finger head-on, the digital arteries are located at ten, two, four and eight oclock.
On the anterior aspect of the wrist, the radial and ulnar arteries can be palpated as demonstrated.Alternatively, the radial artery can sometimes be palpated in the anatomical snuffbox.
The Allen test is performed to evaluate for vascular patency in the setting of an injury or prior to
an arterial puncture. All of the digits are flexed which will empty the hand of blood. Both the
radial and ulnar arteries are occluded by the examiner. The hand is then gently opened. As you
can see, the hand appears pale.
The ulnar artery is then released and the hand evaluated for color change. Capillary refill should
occur in less than five seconds. The test is then repeated on the radial artery and the time noted as
well. Prolonged filling times are consistent with a vascular injury or thrombus.
Evaluating the vascular supply to specific fingers can be a little trickier. The color of the digit inquestion is often a clue. If it is blue or cold, that is an indication that it is not receiving adequate
blood supply. Capillary refill is also clinically useful way to evaluate whether a digit is
adequately perfused.
Capillary refill is generally brisk and occurs in less than two seconds. Prolonged refill times are
consistent with vascular compromise. The Allen test, similar to the one used to evaluate for radial
and ulnar artery patency can also be applied to the digits. The digit in question is flexed, thereby
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exsanguinating it of blood. The clinician occludes the radial and ulnar digital arteries at the base
of the digit. Release of either artery should result in brisk capillary refill to the digit.
Finally, a Doppler ultrasound device can be used to evaluate for vascular patency. A normal,
triphasic flow should be heard over the radial, ulnar and digital arteries.