Mallet Finger
By: McKenna Sobers
6/17/13
AT 3301:
Dr. Jordan Utley, PhD, LAT, ATC
Mallet Finger
Section 1: Introduction to the pathology
Finger injuries are usually not a major injury to most people, and so go unreported most of the time. Deformity is usually associated with these injuries and needs medical attention. With most dislocations however, the patient can self-reduce the dislocation and will not go in for medical attention. Mallet finger is an avulsion of the extensor digitorumlongus tendon.<PHOTO 1: MALLET FINGER BASKETBALL>
Incidence of the Pathology
An avulsion is defined as “a tearing or pulling away of a body part accidentally or surgically” (Merriam-Webster). “Commonly an athletic injury, mallet finger occurs when the outermost joint of the finger is injured. Basketball and baseball players routinely experience jammed fingers, but the injury can occur because of a crushing accident on the job or even because of a cut finger while working in the kitchen” (WebMD, 2005-2013). Mallet finger mostly occurs in sports, but can sometimes occur when doing normal chores around the house.
Etiology
“Mallet finger occurs when an avulsion or rupture of an extensor tendon results in the inability to fully extend the distal phalanx. This occurs when the DIP is forced into flexion, such as when the fingertip is struck with a ball” (Chad Starkey, 2010). The patient may experience pain at the distal phalanx, which will be in flexion. The finger can be passively moved into extension and actively moved into flexion, but is resting in flexion. <PHOTO 2: MALLET FINGER XRAY>
Section 2: Anatomy and Physiology of the Injury
Anatomy
The anatomy of the finger is complex. There are 14 phalanges, 3 for each finger (proximal, middle, and distal), and two for the thumb (proximal and distal). The metacarpophalangeal (MCP), and interphalangeal (IP) joints help the hand with flexion, extension, abduction, and adduction. The joints sit in volar plates which provide joint stability. There are flexor and extensor tendons on each finger that are attached to the PIP and DIP joints to flex and extend the fingers.
Physiology
The stresses that cause mallet finger are a force onto the finger such as when a finger is struck with a ball, or the force of something on the distal part of the finger. As discusses previously, mallet finger is usually caused during sporting events, however, stresses placed on the finger at home doing daily chores can also cause mallet finger.
Section 3: Evaluation of the Injury
Signs and Symptoms
Signs and symptoms of mallet finger include pin, tenderness, swelling at the outermost joint, redness, and the inability to completely extend the finger. When asked to extend the finger the patient can usually do so with assistance, but not actively. “People with mallet finger may delay seeking medical attention, even though they may be in a great deal of pain, simply because they can still use their hand” (Shah).
Special Tests
Because of the deformity and the amount of pain and swelling in the joint after injury there are not many tests that can be done on the finger. However, to test for mallet finger the patient should be tested on the ability to extend the finger. If the test is positive the patient has mallet finger. The mallet finger test tests the ROM of the finger, and the tendenous integrity.
The patient should be sitting with the forearm in pronation and the hand relaxed on a table or other surface. The examiner should hold the hand steady and isolate eh involved finger by holding it at the middle phalanx. While the examiner hold the hand still and isolates the involved finger, the patient should be relaxed. Next, the examiner should instruct the patient to try to extend the finger at the DIP joint. The test is positive if the patient cannot extend the finger at the DIP joint. (Alabama) <VIDEO 1: CLINICAL CASE>
Section 4: Associated Differential Diagnoses
A mallet finger injury is a lot like jersey finger. They are similar in that they are both usually injured during sports such as basketball, soccer, or hockey. In a jersey finger injury the patient cannot actively flex the distal phalanx unlike the mallet finger’s inability to extend the distal phalanx. Jersey finger is usually caused when an athlete grasps another athlete’s jersey and forces the finger into extension as the finger is attempting to flex to hold onto the athlete’s jersey. The way to differentiate the two injuries is by performing the mallet test to test the finger for active extension.
Section 5: Prognosis and Recent Research
Prognosis
Treatment for mallet finger has two different options. The first is non-operative, and the second, operative. In non-operative treatment the finger should be splinted in extension at the DIP joint for 6-8 weeks. Hyperextension of the joint should be avoided, and the therapist should begin flexion exercises with the patient after 6 weeks.
Operative treatment can be done by a simple pin fixation and dorsal blocking pin or by surgical reconstruction of the terminal tendon. This may be done with direct repair/tendon advancement, tenodermodesis, or spiral oblique retinacular ligament reconstruction. (Abbasi)
Recent Research
“Although common, mallet finger represents a spectrum of injuries for which there are many questions about the best form of treatment. A long-standing controversy continues as to strategies and techniques of treatment” (John P. Geyman). In a study of 41 mallet finger injuries, researchers treated 77% conservatively by splintage, and patient satisfaction was 83% with conservative treatment. Successful outcomes of surgical repairs were 85%. The researchers concluded that conservative treatment of at least 80% of mallet finger injuries is safe, effective, well accepted by patients and cost efficient compared with surgical treatment. Research is ongoing on which types of treatment are best for mallet finger. More will be known about treatment with the more experience surgeons, therapists, and researchers have with mallet finger.
Works Cited
Abbasi, David. Orthobullets. 29 May 2013. 20 June 2013. <
Alabama, University of West. Mallet Finger Test. n.d. website. 20 June 2013. <at.uwa.edu/special%20tests/specialtests/upperbody/mallet.htm>.
Chad Starkey, Sara D. Brown Jeff Ryan. Examination of Orthopedic and Athletic Injureis. Philidelphia : F.A. Davis Company, 2010.
Hand, American Society for Surgery of the. "X-rays of mallet finger." 2013. <
Jeffrey C. Leggit, Christian J. Meko. Acute Finger Injuries: Part 1. Tendond and Ligaments. 1 March 2006. Website. 20 June 2013. <
John P. Geyman, Kenneth Fink, Sean D. Sullivan. "Conservative Vs. Surgical Treatment of Mallet Finger: A Pooled Quantitative Literature Evaluation." Journal of the American Board of Family Medicine (2005): 336-344. Journal Article. <
Merriam-Webster. Merriam-Webster Encyclopedia. 2013. 17 June 2013. <
Oller, Dr. "Mallet Finger: Clinical Case." 2012. <
Rehak, David C. "Finger Injuries in Basketball Players." n.d. Picture. <
Shah, Sachin J. eMedicine Health. 2013. Website. 20 June 2013. <
WebMD. Fitness and Exercise. 2005-2013. 17 June 2013. <