Thumb RCL Injury S63.649A 842.12

ICD-9 Classification / Treatment
Etiology / Natural History Associated Injuries / Differential Diagnosis
Anatomy Complications
Clinical Evaluation Follow-up Care
Xray / Diagnositc Tests Review References


Thumb RCL Injury ICD-10

A- initial encounter

D- subsequent encounter

S- sequela


Thumb RCL Injury ICD-9

  • 842.12 (Sprains and strains of metacarpophalangeal joint of hand)

Thumb RCL Injury Etiology / Epidemiology / Natural History

  •  1/10 as common as UCL injury
  • caused by extension and adduction injuries

Thumb RCL Injury Anatomy


Thumb RCL Injury Clinical Evaluation

  •  tenderness at ligament origin and insertion
  • pain exacerbated by torsional motions such as turning doorknobs or with axial compression such as pushing in buttons on car doors.
  • 30 degrees increased laxity in extension and 30 degrees flexion to ulnar deviation as compared to uninjured side =  complete rupture.
  • Partial injuries will have firm end-point

Thumb RCL Injury Xray / Diagnositc Tests

  •  PA, lateral and oblique views.  Generally normal; occasionally proximal phalanx may be deviated ulnarly; may have avulsion fragment.  Palmar subluxation is common

Thumb RCL Injury Classification / Treatment

  • Partial tear (have firm end point on exam) = thumb spica cast 4-6 wks
  • Complete tears =  operative repair

Thumb RCL Technique

  • “lazy S” incision
  • dorsal branch of radial sensory nerve gently retracted
  • abductor aponeurosis incised longitudinally exposing ligament and joint
  • inspect for intraarticular patholoty
  • tear isoloated
  • mibsubstance tear=repair with 4-0 ethibond, incorporate part of palmar plate with deepest suture
  • bony avulsions repaired with pull-out suture(monofilament passed with Keith needles) over button, or Mitek mini-anchors; +/- k-wire fixation of joint
  • close abductor aponeurosis with 4-0 pds, skin 5-0 chromic

Thumb RCL Injury Associated Injuries / Differential Diagnosis


Thumb RCL Injury Complications

  • instablity (more common with non-operative treatment)
  • limitation of motion
  • hypestesia
  • infection

Thumb RCL Injury Follow-up Care

  •  thumb-spica cast for 4-6 wks
  • customized thermoplastic “thumb cone” splint.  ROM exercises
  • two weeks after cast start full AROM
  • 3 wks out of cast start strengthening, wean out of splint.

Thumb RCL Injury Review References

  • Durham JW, J Hand Surg 18;232:1993