Jersey Finger
DEFINITION
• Rupture or avulsion of the flexor digitorum profundus (FDP).
• Classification is based on how far the tendon retracts,which in turn will affect the success of surgical repair.
A type I injury retracts all the way to the palm.The vincula brevis and longus are ruptured and blood supply is interrupted. Extensive scarring can develop within the tendinous sheath,therefore surgical repair is indicated within 7 to 10 days.
Type II retracts to the PIP joint.The long vinculum may still be intact, and a small chip of bone may be avulsed with the tendon.The avulsed end may become entrapped at the flexor digitorum superficialis (FDS) chiasma, causing a flexion contracture.
Type III occurs when a bony fragment is avulsed and remains attached to the tendon,which isthen unable to retract through the pulley.The tendon remains in the synovial sheath.
Jersey-Finger
SYNONYMS
• FDP avulsion
• Rugby finger
ETIOLOGY
• Rupture or avulsion of the FDP tendon can occur during activities that require sustained digital flexion against forceful or unexpected resistance, resulting in hyperextension of the DIP joint and rupture of the FDP tendon.
• Rupture of the FDP tendon commonly occurs when an athlete’s finger catches on another player’s clothing in sports such as football.
EPIDEMIOLOGY AND
DEMOGRAPHICS
Ring finger (fourth digit) is the most common involvement. It is the weakest and accounts for 75% of all cases.
MECHANISM OF INJURY
• Forceful passive extension of the digit while the FDP is in maximal contraction.
• The injury causes forced extension of the DIP joint during active flexion and can occur if the force is concentrated at the middle phalanx or at the distal phalanx.
• Sports such as the following:
Football
Rugby
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COMMON SIGNS AND
SYMPTOMS
• Pain
• Swelling
• Inability to flex the PIP joint
AGGRAVATING ACTIVITIES
• Movement of the affected finger
• Gripping
• Lifting activities
• Shaking hands
EASING ACTIVITIES
• Rest
• Splinting
• Ice
24 Hours SYMPTOM PATTERN
• Pain consistent with movement (e.g.,lifting or weight bearing with the affected hand).
• If left untreated, inflammation can lead to fibrosis of the FDP tendon and quadriga.
PAST HISTORY FOR THE REGION
• There may be a history of repetitive movements requiring flexion against resistance.
• Trauma caused by a sudden unexpected force that occurs while trying to maintain a grip on a rope, such as might occur while restraining a dog on a leash,or holding onto a jersey during a football game.
• Tendon may have been weakened by steroid use or disease processes that weaken tendon integrity.
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PHYSICAL EXAMINATION
• A patient with jersey finger may present with pain and swelling at the palmar aspect of the DIP joint.
• The finger may be extended with the hand at rest because of lack of flexor counterforce.
• There may be a tender fullness or lump if the tendon has been retracted.
• Palpation to the involved palm will be painful and may reveal the retracted distal end of the ruptured tendon.
IMPORTANT OBJECTIVE TESTS
• The integrity of the FDP tendon can be tested by stabilizing the MCP and PIP joints in extension while having the patient attempt to flex the DIP. If the patient is unable to flex the DIP,the tendon is ruptured.
• The FDS tendon can be evaluated and differentiated from the profundus by holding the unaffected fingers in extension and asking the patient to flex the injured finger. An injured FDS tendon will produce no movement.
• Ultrasound of the flexor sheath to visualize the location and status of the avulsed end of the tendon can be used.
• X-rays will generally not reveal pathology, MRI scans can be used, but the results should be backed up by other clinical findings.
• Strength will reveal weakness of the FDP and ROM testing may reveal hypermobility into DIP extension. In the case of long-term pathology, extension may be limited by scar tissue and adhesions.
DIFFERENTIAL
DIAGNOSIS
• Anterior interosseous nerve paralysis
• Trigger finger
• Swan-neck deformity
• Jammed finger
CONTRIBUTING FACTORS
• Any activity requiring repetitive resisted flexion such as participation in contact sports, walking the dog, or starting a lawnmower.
• Long-term steroid use.
• Endocrine system pathology.
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TREATMENT
SURGICAL INDICATORS
• Type I injuries: Surgical repair is indicated within 7 to 10 days because of the risk of inflammation and scarring at the end of the ruptured tendon,making it impossible to thread the tendon back through the tendinous sheath.
• Type II injuries: Surgical repair is indicated within up to 4 weeks from the date of injury.
• Type III injury: Surgical repair can be successful after 4 weeks because the distal end of the tendon has not retracted all the way through the synovial sheath.
SURGICAL OPTIONS
• Type I injuries: The distal end of the tendon must be trimmed because of the lack of blood supply. Likelihood of success decreases with time: Surgery is indicated within 7 to 10 days of injury because of the inflammatory response. Surgical options beyond this time frame include tendon excision and DIP fusion.
• Type II injury:The flexor tendon must be reattached and can be rethreaded with a silicone flexible tendon.
• Type III injury:The flexor tendon must be reattached.
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SURGICAL OUTCOMES
• Injury to the A4 pulley may impair DIP flexion.
• Tethering or fibrosis of the FDP tendon (quadriga) caused by scarring may result in loss of ROM and decreased grasp strength in the remaining digits.
• Type I injury: Repair can be difficult if the tendon has retracted all the way into the palm because of inflammation,avulsed vinculum, and inability to rethread the tendon. This may result in compromised PIP ROM.
• Type II injury: Blood supply and vinculum remain intact. Fibrosis at the FDS chiasm may impair tendon gliding.
• In the case of a chronic rupture, or a type II or III injury more than 4 weeks since the injury, consideration should be given to whether there is enough of a functional impairment to warrant intervention. Tenodesis, arthrodesis, or free tendon grafting may also be considered.
REHABILITATION
• Postsurgical repair
Forearm-based dorsal block splint for 4 to 5 weeks with wrist and MCPs at 30 degrees of flexion and IPs in full extension.The involved finger should be held at 45 degrees of DIP flexion,positioning the FDP tendon proximal to the skin incision.
In general, active finger and wrist flexion and passive finger extension are contraindicated for the first 3 to 4 weeks.
Passive wrist and finger flexion and passive wrist extension are allowed. Functional movement of the hand is allowed after 4 weeks, and splint may be discontinued at 5 weeks.
Resistance should be avoided for 7 to 8 weeks.
• Nonsurgical repair
Resection of the retracted tendon and/or DIP joint fusion.
If there are minimal functional impairments, further intervention is not required.
REHABILITATIVE
COMPLICATIONS OF JERSEY
FINGER
• If the tendon is not repaired surgically, there is an increased risk of continued pain in the palm and finger and possible development of carpal tunnel syndrome caused by inflammation.
• Quadriga may occur because of adhesions or scarring of the involved digit restricting flexion of the other digits. Pain may persist in the palm or involved digit.
PROGNOSIS
• Average recovery expected is as follows:
75% of grip strength
77% of finger pressure
75% of pinch strength
76% of PIP motion
75% of DIP motion
SIGNS AND SYMPTOMS
INDICATING REFERRAL
TO PHYSICIAN
Because of the critical nature of the timing of surgical repair, a suspected FDP rupture must be referred immediately to a physician for assessment.
SUGGESTED READINGS
1- Bois AJ, Johnston G, Classen D. Spontaneous flexor tendon ruptures of the hand: Case series and review of the literature. J Hand Surg Am. 2007;32:1061–1071.
2- Hankin FM, Peel SM. Sport-related fractures and dislocations in the hand. Hand Clin.1990;6:429–453.
3- Hofmeister EP,Craven CE. Zone I rupture of the flexor digitorum profundus tendon caused by blunt trauma:A case report. J Hand Surg Am. 2008;33:247–249.
