Arundel et al reported the East Riding Elbow Rule (ER-squared) for evaluating an adult for elbow fracture. The rule can help to decide if an X-ray is required. The authors are from Hull Royal Infirmary in England.

Patient selection: adult (all pediatric patient were X-rayed)


The anterior and posterior aspect of the elbow were each divided into quadrants (total 8).

(1) anterior lateral humerus

(2) anterior medial humerus

(3) anterior radius

(4) anterior ulna

(5) posterior lateral humerus and medial epicondyle

(6) posterior medial humerus

(7) posterior radius

(8) posterior ulna and medial epicondyle


Key findings to look for:

(1) inability to fully extend the elbow

(2) tenderness over the radial head, olecranon and medial epicondyle

(3) presence of bruising


Indications for performing an X-fay:

(1) tender anterior forearm over radial head (anterior, quadrant 3)

(2) tender over radial head (posterior, quadrant 8)

(3) any bruising

(4) tender olecranon or medial epicondyle (posterior, quadrant 5)


Although not part of the flow diagram, inability to extend the elbow may be a fifth indication to perform an X-ray based o the study of Appelboam et al.



• The sensitivity was 100% and specificity 24%.

To read more or access our algorithms and calculators, please log in or register.