Criteria

Narakas classification[13][14]​​

Defines the injured nerves and directs attention to potential areas of concern during recovery.

  • Group 1: C5-C6 injury (upper Erb's palsy)

    • Paralysis of shoulder and biceps

    • Rate of spontaneous recovery >80%

  • Group 2: C5, C6, C7 injury (extended Erb's palsy)

    • Paralysis of shoulder, biceps, and wrist extensors

    • Rate of spontaneous recovery around 60%

  • Group 3: C5, C6, C7, C8, T1 injury (total palsy with no Horner's sign)

    • Paralysis of entire limb

    • Rate of spontaneous recovery <50%

  • Group 4: C5, C6, C7, C8, T1 injury (total palsy with Horner's sign)

    • Paralysis of entire limb with Horner's sign

    • Rate spontaneous recovery around 0%.

Modifications (including an extended Narakas classification with 5 groups) have been described but are rarely used.[12][14]

Seddon classification[85]

Severity of the nerve injury determines the potential for recovery. Complete rupture will require surgical repair, whereas stretch injury will often recover with time:

  • Neurapraxia: stretch injury of the nerve

  • Axonotmesis: rupture of the axon with intact nerve sheath

  • Neurotmesis: complete rupture of the nerve.

Toronto test score[53]

  • Defines the injured area in relation to 5 observed movements of the hand and elbow

  • Does not assess shoulder function

  • Graded on a scale of 0 (no motion) to 2 (normal full motion); can add up to a maximum of 10 points for the 5 movements assessed. Lower scores indicate patients who may benefit from nerve repair surgery.

Active movement scale[48][54]

  • Defines the injured nerves and can be used to monitor recovery from the initial injury and after surgical repair

  • Consists of observation of movements of multiple joints and muscle groups, including shoulder function

  • More global than the Toronto test score

  • Each 1 of 15 different active upper-extremity movements is tested without gravity and against gravity and is scored on a scale of 0 to 7.

Mallet scale[55]

  • Evaluates shoulder function in older patients who can cooperate with instructions

  • Can be used to follow function over time and to evaluate the outcomes of surgical interventions

  • Uses a grading scale of 1 (no movement) to 5 (normal motion; symmetric to the unaffected, contralateral side) for each of the 5 voluntary movements tested

  • A modified Mallet classification is most commonly used, for which categories 1 and 5, belonging to either totally paralysed or normal children, have been eliminated.

Medical Research Council motor scale[57]

Commonly used to evaluate muscle strength, but use in babies is controversial as they cannot follow instructions.

  • 0: no movement

  • 1: flicker of movement but no active movement

  • 2: active movement with gravity eliminated

  • 3: anti-gravity movement

  • 4: movement against some resistance

  • 5: normal power.

Use of this content is subject to our disclaimer