Ring Avulsion Injuries

Ring Avulsion Injuries

Evan H. Horowitz

Michael Guju

Francisco A. Schwartz-Fernandes


  • Definition

    • Acute trauma to a finger caused by a sudden force on a ring, leading to skin and soft tissue damage.1

    • Ring avulsion injuries vary in severity, ranging from bruising to traumatic amputation of the finger.1

    • Such injuries often occur to people who work with machinery while wearing a ring.1

  • Incidence and risk factors

    • Incidence

      • Wearing a ring or wedding band accounts for 90% of finger avulsion cases that are treated in hospital departments and 13% to 15% of digit amputations per year.2

      • Average ratio of 300 cases per year for a population of 60 million in industrialized countries.2

    • Risk factors/epidemiology

      • Young men, average age 31 years at highest risk2

        • Majority of patients of age 21 to 40 years, commonly working men3

      • Occupational hazards involving the use of hands to operate machinery and/or lift heavy objects


  • Mechanism

    • Ring gets caught and anchored on a heavy, moving object such as a door, fence, or piece of heavy machinery. As the object continues to move, the ring may avulse the underlying tissues.

    • Biomechanics (Table 57.2)

      • The average maximum force resulting in class I injuries is 80 N.4

      • The average maximum force producing amputation in class III injuries was 154 N. Force measurements for class II injuries were nearly identical to those of class III.4

  • Prognosis

    • The extent of artery, vein, and nerve involvement varies and can be used to classify these injuries and determine prognosis.1,18

    • Recent advancements in microsurgery,5 such as revascularization and replantation, have improved prognosis and outcomes.6

    • Kay et al concluded that extent of skeletal injury is a significant prognostic factor and proposed a revision of the Urbaniak et al classification.7

TABLE 57.1 The Urbaniak Classification of Avulsion Injuries and the Kay Classification With adani Modifications1,5,7,14

Urbaniak Classification


Avulsion injury with adequate circulation


Incomplete avulsion injury with inadequate circulation


Avulsion injury with complete degloving or amputation

Kay Classification as Modified by Adani


Avulsion injury with adequate circulation


Incomplete avulsion injury with inadequate arterial or venous circulation, no skeletal injury

IIa Arterial circulation inadequate only

IIv Venous circulation inadequate only


Incomplete avulsion injury with inadequate arterial or venous circulation, fracture or joint injury present

IIIa Arterial circulation inadequate only

IIIv Venous circulation inadequate only


Avulsion injury with complete degloving or amputation

IVp Complete avulsion injury with amputation proximal to FDS insertion

IVd Complete avulsion injury with amputation distal to FDS insertion

FDS, flexor digitorum superficialis.

TABLE 57.2 Tensile Strengths of Rings based on Their Type and Material, and the Common Classes of Injuries Associated With Different Rings2

Type of Ring


Average Tensile Strength (N)

Type of Injuries

Open ring

Nickel-free alloy or silver


Class I injuries

Bejeweled, squared closed, or signet ring

Steel, resin Plexiglas, or Sumac wood


Class I-III Injuries (at up to 351 N, risk of severe impairment, or class III and IV, is limited to 14% of cases)

Closed, three-strand braided, or signet ring

Jade, aluminum, silver, gold-plate, or steel


Very high risk of class IV injuries

Only gold members can continue reading. Log In or Register to continue

May 7, 2019 | Posted by in ORTHOPEDIC | Comments Off on Ring Avulsion Injuries
Premium Wordpress Themes by UFO Themes