Abuse should be considered if:

• multiple fractures
• rib fractures (7 in 10 NAI)
• femoral fracture (see below)
• Under 3 with humeral fracture (1 in 2 NAI)
• Mid shaft humeral fracture more frequently NAI, supracondylar less frequently
• Infant/toddler skull fracture (1 in 3 NAI).  Type and location not helpful

Formerly known as CORE Info, the RCPCH Child Protection Portal hosted on the RCPCH website provides evidence-based guidance for health professionals concerned about non-accidental injury 

• Fractures in the abuse group occurred predominantly in children less than 1 year of age.
• Femoral fractures under 1 year of age are significantly associated with abuse.
• One-third of isolated femoral fractures under 3 years of age were abusive.
• Abusive femoral fractures occur predominantly in infants (evidence level IIb) [3].
• Significantly more abusive femoral fractures arise in children who are not yet walking (evidence level IIb) [3].
• Mid-shaft fractures are the most common fracture in both abuse and non-abuse groups (analysed for all age groups) (evidence level IIa) [3].
• Under 15 months of age, a spiral fracture is the most common type of abusive femoral fracture p=0.05 (evidence level IIb) 

2014 Systematic review on bites has been withdrawn pending new review – interim advice on RCPCH child protection portal but need to be member.

Rib fractures with callus are at least 2 weeks old.  Other than that, unable to date.

Systematic reviews of various NAI issues at https://childprotection.rcpch.ac.uk/child-protection-evidence/