Boutonnière Deformity
DEFINITION:
A boutonnière deformity (BD) consists of proximal interphalangeal (PIP) joint
flexion and distal interphalangeal (DIP)
joint and MCP joint hyperextension of the finger.
 |
| Boutonniere , Deformity , Finger , Joint, Flexion |
SYNONYM:
Buttonhole deformity
ETIOLOGY:
• BD begins with flexion of the PIP joint that is caused by a disruption of the common extensor tendon (central slip) that inserts on the base of the middle phalanx.This disruption results in the lateral bands migrating volarly to the PIP joint
axis as the head of the proximal phalanx
moves dorsally through the “hole” created by the central slip rupture.
• BD can occur as the result of:
mechanical trauma,rheumatoid arthritis (RA), burns and infections.
Trauma to the PIP joint may result in a laceration involving the central slip.Axial loading or forced flexion with the PIP in extension can cause
closed disruption of the central slip.
closed disruption of the central slip.
Volar dislocation of the PIP can cause avulsion of the central slip, as well.
• Chronic synovitis of a PIP joint with RA results in a slow, forced flexion.
This causes the elongating of the central slip and ultimately leads to rupture.
Subsequent volar displacement of the lateral bands below the axis of the PIP rotation creates increased tension on the DIP
extensor mechanism, leading to hyperextension and limited flexion of the DIP.
• The difference between a fixed and a flexible boutonnière deformity is that
a flexible BD is one in which the PIP joint can be passively extended.This is normally observed in acute or subacute
cases. Rigid BDs are those in which the PIP joint cannot be extended with
PROM as a result of oblique retinacular ligament (ORL) tightness.This occurs in
more chronic and untreated cases.
EPIDEMIOLOGY AND DEMOGRAPHICS:
Up to 50%of patients with RA are estimated to develop a BD in at least one digit.
MECHANISM OF INJURY:
• Jamming the finger on the ground or another player in contact sports.
• Burns
• Lacerations
COMMON SIGNS AND SYMPTOMS:
Swelling and dorsal PIP joint tenderness to palpation.
AGGRAVATING ACTIVITY:
Continued flexion with gripping activities.
EASING ACTIVITIES:
• Rest will prevent aggravation of symptoms.
• Avoidance of flexion activities may slow progression of deformity.
• Early treatment and diagnosis will limit the discomfort.
24-HOUR SYMPTOM PATTERN:
BDs are usually are not recognized in the early stages. As a result,many go untreated and become painful, chronic injuries. If a BD is suspected, treat it as such to limit the increased pain and deformity.
PAST HISTORY FOR THE REGION:
• Recent trauma to the involved finger.
• RA (Rheumatoid Arthritis).
• Osteoarthritis of the involved finger.
• Recent burn or infection of the involved finger.
PHYSICAL EXAMINATION:
• PIP joint positioned in flexion, unable to actively extend.
• DIP joint positioned in hyperextension difficult to flex.
 |
| Boutonniere , Deformity , Jamming , Finger , Burn , Lacerations |
IMPORTANT OBJECTIVE TESTS:
• Test for extensor hood rupture:Finger is
flexed to 90 degrees over edge of table.
Patient is asked to extend the involved finger against resistance. The absence
of extension force at the PIP joint and fixed extension of the DIP joint are signs
of rupture of the central slip. Specificity and sensitivity unknown.
• Oblique retinacular ligament tightness test: PIP joint flexed is position of relaxation for the ORL, therefore the DIP
joint should have more flexion than the
PIP joint in extension. Specificity and sensitivity unknown.
DIFFERENTIAL DIAGNOSIS:
• Phalanx fracture.
• Pseudoboutonnière deformity is a
condition marked by PIP joint flexion
contracture and restricted flexion of
the DIP joint. This is commonly found
in patients with RA. The characteristic hyperextension of the DIP joint in
boutonnière deformity is not present. It often is the result of a hyperextension injury causing inflammation and
contracture of the checkrein ligaments the oblique retinacular ligaments,
and possibly the first cruciate pulley. Pseudoboutonnière deformity must be
distinguished from boutonnière deformity because pathophysiology and
treatment are different.
CONTRIBUTING FACTORS:
• Participation in contact sports.
• RA significantly increases the chances of having a boutonnière deformity.
TREATMENT
SURGICAL INDICATORS
Surgery may be indicated after conservative splinting treatments have failed
or the injury is more than 8 weeks old. The patient and hand surgeon must
carefully weigh and measure the risks and benefits before embarking on surgical planning.
 |
| Surgical , Splint , K-Wire , Slip , Tendon |
SURGICAL OPTIONS:
• When the central slip is avulsed with a bone fragment, the fragment should be either fixed or excised and the tendon reattached. The PIP joint then is held in extension with a Kirschner wire (K-wire) for a minimum of 10 days, followed by splinting.
• When the central slip is avulsed with a bone fragment, the fragment should be either fixed or excised and the tendon reattached. The PIP joint then is held in extension with a Kirschner wire (K-wire) for a minimum of 10 days, followed by splinting.
• In closed volar dislocations warranting surgery or in open injuries, open
reduction and repair of all soft tissue structures should occur, followed
by stabilization of the PIP joint with a K-wire for at least 3 weeks. The PIP joint then is splinted for at least
another 3 weeks while DIP joint motion is encouraged.
• Many surgical techniques have been described to repair a BD. The method
for repair is determined by the condition of the central tendon and lateral
bands.A sample of the many described techniques is as follows:
Using the superficial flexor tendon to reconstruct the central slip.
Using the lateral band on one side to reconstruct the central slip, while on
the other side it is elongated to make use of a single lateral band.
Repositioning the lateral bands dorsally.
Separating the extrinsic and inter-osseous tendon from the lumbrical and oblique retinacular ligaments and centralize the lateral bands.
SURGICAL OUTCOMES:
Deformities that can be passively corrected before surgery have better outcomes than those that remain rigid.
Rigid deformities require extensive surgical release to correct, therefore putting
the patient at risk for new postsurgical deformities.
REHABILITATION:
• For deformities that the examiner is able to passively extend the PIP to 0 degrees,
rehabilitation is as follows:
Edema control as needed, static splinting for PIP extension up to 6 weeks with full time wear.The splint
should not interfere with MCP or DIP joint ROM. Initiate isolated DIP flexion exercises. Following the 6 weeks of total extension, flexion of the PIP
joint is carefully initiated. Two to 4 weeks of extension should be continued following the initiation
of flexion activities. Splinting is recommended only at night when full active extension is achieved and is maintained for subsequent visits.
• For patients with rigid PIP flexion contractures,rehabilitation is as follows:
Static PIP extension splinting for up to 8 weeks to regain full extension.The
clinician may need to use serial casts that are changed weekly, depending
on ROM progression. Continue isolated DIP flexion exercises. Resistant
BDs may require treatment 6 to 9 months after injury, with full ROM requiring a full year of rehabilitation.
PROGNOSIS:
• Prognosis is generally good for acute injuries and RA. Rarely will contracture
and pain result in the need to amputate the digit.
• Participation in contact sports significantly increases your chances of having a BD.
SIGNS AND SYMPTOMS INDICATING REFERRAL TO PHYSICIAN:
• If the patient reports trauma to the joint and a fracture is suspected, the patient
should be referred to a hand surgeon for imaging studies.
• Patients with injuries not responding to conservative treatment of splinting and
serial casting after 8 weeks should be referred to a hand surgeon.
 |
| Boutonniere , Deformity , PIP , DIP |
SUGGESTED READINGS:
1- Coons MS, Green SM. Boutonnière deformity.Hand Clin. 1995;11(3):387–402.
1- Coons MS, Green SM. Boutonnière deformity.Hand Clin. 1995;11(3):387–402.
2- Harrison BP, Hilliard MW. Emergency department evaluation and treatment of hand injuries. Emerg Med Clin North Am.
1999;17(4):793–822.
3- Massengill JB.The boutonnière deformity.Hand .Clin. 1992;8(4):787–801.
4- Towfigh H, Gruber P. Surgical treatment of the boutonnière deformity. Oper Ortho Traumatol. 2005;17(1):66–78.
AUTHOR: AUDRA PONCI BADO
