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Perilunate Dislocation, Emergency Medicine

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Perilunate Dislocation, Emergency Medicine

Basics

Description

Scaphoid is frequently fractured with perilunate dislocations.

Diagnosis is frequently missed on clinical exam.

Although perilunate dislocation is unusual in pediatric patients, children with wrist pain should be splinted and referred to a pediatric hand surgeon.

  • Lunate remains located and in line with the radius but the distal carpal bones are displaced dorsally ( ’ ˆ Ό95% of the time) or volarly ( ’ ˆ Ό5% of the time)
  • Early surgical treatment is recommended.
  • This injury has a high incidence of post-traumatic arthritis.

Etiology

  • Mechanism of injury is usually wrist hyperextension with ulnar deviation.
  • These are high-energy injuries:Falls from a heightMotor vehicle accidentsIndustrial accidentsSporting accidents
  • Falls from a height
  • Motor vehicle accidents
  • Industrial accidents
  • Sporting accidents

Diagnosis

Signs and Symptoms

  • Severe wrist pain
  • Wrist swelling
  • Diffuse wrist tenderness
  • Paresthesias in the median nerve distribution
  • History of a high-energy injury
  • Any concomitant injuries
  • Pain in the wrist
  • May complain of paresthesias in the median nerve distribution
  • Wrist swelling
  • Possible deformity of the wrist
  • Decreased range of motion of the wrist
  • Possible decreased sensation in the median nerve distribution
  • Special attention should be paid to skin integrity because open fractures are common.
  • Neurovascular status should be monitored closely, including 2-point discrimination.
  • Check closely for concomitant injuries, specifically of the upper extremity.

Essential Workup

Diagnosis Tests & Interpretation

  • Radiographic imaging that includes 3 views of the wrist
  • Perilunate dislocation visualized best on the true lateral view:Distal carpal row, specifically the capitate, seen dorsally (95% of the time) or volarly (5% of the time) in relation to the lunateLunate is located and in line with the radius
  • CT and MRI are not generally needed for diagnosis, but some orthopedists may request them for preoperative planning.
  • Distal carpal row, specifically the capitate, seen dorsally (95% of the time) or volarly (5% of the time) in relation to the lunate
  • Lunate is located and in line with the radius
  • Wrists are rarely sprained in children.
  • Wrist radiographs are difficult to interpret in pediatric patients.
  • Comparison view of the other wrist may be helpful.

Differential Diagnosis

  • Lunate fracture
  • Lunate dislocation:Dislocation occurs between lunate and distal radius.
  • Scapholunate dissociation and other similar ligamentous disruptions
  • Distal radius fracture
  • Dislocation occurs between lunate and distal radius.

Treatment

Pre-Hospital

  • Assess for other injuries
  • Immobilize
  • Pain control
  • Elevate

Initial Stabilization/Therapy

  • Identify other, more serious, associated injuries.
  • Immobilize
  • Elevate
  • Ice

Ed Treatment/Procedures

  • Pain control
  • Procedural sedation for closed reduction:Etomidate: 0.1 " “0.15 mg/kg IVMethohexital: 1 " “1.5 mg/kg IVPropofol: 40 mg IV every 10 sec until induction
  • Closed reduction of the dislocation should be done emergently:Arm is hung in traction for 10 min with 10 " “15 lb of counterweights and the fingers in traps.The fingers are then removed from the traps and manual traction is continued.One of the physicians thumbs is placed volarly over the lunate and then the injury is recreated with wrist extension.Continued traction is applied to the wrist and then slow flexion of the wrist is performed, which usually locates the distal carpal bones.
  • Operative fixation to reduce and maintain wrist stability is required.
  • Immobilize wrist using a sugar-tong splint in neutral position. Obtain postreduction radiograph.
  • Etomidate: 0.1 " “0.15 mg/kg IV
  • Methohexital: 1 " “1.5 mg/kg IV
  • Propofol: 40 mg IV every 10 sec until induction
  • Arm is hung in traction for 10 min with 10 " “15 lb of counterweights and the fingers in traps.
  • The fingers are then removed from the traps and manual traction is continued.
  • One of the physicians thumbs is placed volarly over the lunate and then the injury is recreated with wrist extension.
  • Continued traction is applied to the wrist and then slow flexion of the wrist is performed, which usually locates the distal carpal bones.

Medication

  • Diazepam: 2 " “5 mg IV q2 " “4h (peds: Max. dose is 0.25 mg/kg q4h) PRN anxiety
  • Fentanyl: 0.05 " “0.2 mg IV q1h PRN pain
  • Hydromorphone: 0.5 " “1 mg IV q4 " “6h (peds: 0.015 mg/kg/dose q4 " “6h) PRN pain
  • Lorazepam: 0.5 " “1 mg IV q1 " “6h (peds: 0.044 mg/kg q4 " “6h) PRN anxiety
  • Morphine sulfate: 0.1 mg/kg IV q1h PRN pain

Follow-Up

Disposition

  • Open dislocation, presence of multiple trauma, or other, more serious, injuries
  • Inability to reduce dislocation or maintain reduction
  • Neurovascular compromise
  • Closed injuries
  • Adequate reduction
  • No neurovascular involvement
  • Orthopedic follow-up within 2 " “3 days

Follow-Up Recommendations

  • All patients with a perilunate dislocation must follow-up with a hand surgeon for surgical stabilization and ligament repair.
  • Follow-up should be within 2 " “3 days.

Pearls and Pitfalls

  • Up to 25% of these injuries are missed on initial presentation.
  • In a patient with wrist pain, swelling, and limited range of motion, it is important to obtain adequate x-rays of the wrist and make sure that the lunate and capitate are located in their fossa on the lateral wrist x-ray.
  • Late presentation of these injuries leads to a very poor outcome and often requires a salvage operation.
  • Complications include median nerve injury, tendon problems, complex regional pain syndrome, wrist instability, and post-traumatic arthritis.
  • Even with appropriate treatment, there is a high incidence of post-traumatic arthritis and loss of grip strength.

Additional Reading

  • Budoff ‚ JE. Treatment of acute lunate and perilunate dislocations. J Hand Surg Am. 2008;33A:1424 " “1432.
  • Forli ‚ A, Courvoisier ‚ A, Wimsey ‚ S, et al. Perilunate dislocations and transscaphoid perilunate fracture-dislocations: A retrospective study with minimum ten-year follow-up. J Hand Surg Am. 2010;35:62 " “68.
  • Kardashian ‚ G, Christoforou ‚ DC, Lee ‚ SK. Perilunate dislocations. Bull NYU Hosp Jt Dis. 2011;69(1):87 " “96.
  • Melsom ‚ DS, Leslie ‚ IJ. Carpal dislocations. Curr Orthoped. 2007;21:288 " “297.
  • Stanbury ‚ SJ, Elfar ‚ JC. Perilunate dislocation and perilunate fracture-dislocation. J Am Acad Orthop Surg. 2011;19(9):554 " “562.

See Also (Topic, Algorithm, Electronic Media Element)

  • Carpal Fractures
  • Lunate Dislocation
  • Scaphoid Fracture

Codes

ICD9

  • 814.01 Closed fracture of navicular [scaphoid] bone of wrist
  • 833.09 Closed dislocation of wrist, other

ICD10

  • S62.009A Unsp fracture of navicular bone of unsp wrist, init
  • S63.095A Other dislocation of left wrist and hand, initial encounter
  • S63.096A Other dislocation of unspecified wrist and hand, initial encounter
  • S63.094A Other dislocation of right wrist and hand, initial encounter

SNOMED

  • 263026000 Dislocation of perilunate joint (disorder)
  • 281513007 Transscaphoid-perilunate fracture dislocation (disorder)
  • 209270002 Closed fracture dislocation perilunate (dorsal) (disorder)
  • 281518003 Volar transscaphoid-lunate fracture dislocation (disorder)
  • 209269003 Closed fracture dislocation lunate (volar) (disorder)