Peter Hunt
Consultant
CTP Insurance, Insurance
Can Injury Sustained During Consequential Treatment be a “Non-Threshold” Injury?
18 August, 2025
In Brief
- At Common Law, injury sustained during the application of reasonable and necessary treatment may have been caused by the motor accident unless the treatment is grossly negligent.
- A right shoulder injury sustained as a consequence of a fall caused by leg weakness following a cortisone injection was, therefore, caused by the accident.
- The Court of Appeal has previously doubted, however, whether injury sustained during consequential treatment is an “injury” for the purpose of section 1.4 of the Motor Accident Injuries Act 2017 (MAIA) – see Mandoukos v Allianz Australia Insurance Limited [2024] NSWCA 71.
Facts
The Personal Injury Commission (PIC) published its decision in Allianz Australia Insurance Limited v Miles (No 3) [2025] NSWPICMP 565 on 15 August 2025.
On 30 April 2022, the Claimant approached a roundabout with the intention of turning left. Before she could do so, however, the Insured vehicle collided with her vehicle from behind.
The Claimant asserted that she sustained various non-threshold physical and psychiatric injuries which would entitle her to ongoing statutory benefits and common law damages.
Given that the various injuries were raised at different times, there were multiple applications for assessment and further assessment.
This dispute, however, related to whether the accident caused a non-threshold injury to her right shoulder. The original PIC Medical Assessor certified that the motor accident caused a non-threshold injury to the Claimant’s right shoulder in the form of a right rotator cuff tear.
The Insurer submitted that the right rotator cuff tear was caused by a subsequent fall on 18 October 2022, some six months post-accident, and that the motor accident made no causative contribution to the fall.
The Insurer successfully sought referral to the Medical Review Panel.
The Review Panel’s Decision
Was the Right Rotator Cuff Tear Caused by the Accident?
The Review Panel accepted the following chain of causation between the motor accident and the Claimant’s non-threshold, right shoulder injury:
- The motor accident caused a threshold injury to the Claimant’s lumbar spine.
- The lumbar spine injury necessitated a cortisone injection.
- The cortisone injection caused the Claimant’s left leg to give way.
- The Claimant’s fall caused a non-threshold injury to the right shoulder in the form of a high-grade partial thickness supraspinatus rotator cuff tear.
The Review Panel therefore concluded that the motor accident could have medically caused the rotator cuff tear and did, in fact, cause that tear.
In coming to this conclusion, the Review Panel applied the High Court’s decision in Mahony v J Kruschich (Demolitions) Pty Ltd [1985] HCA 37; (1985) 156 CLR 522, which remains the leading authority for the proposition that the original tortfeasor remains liable for any additional injury caused during treatment for an accident-related injury unless the treatment can be characterised as grossly negligent.
Was the Right Rotator Cuff Tear an “Injury”?
Having found that causation was established, the Review Panel proceeded to consider whether the right rotator cuff tear was an “injury” within the meaning of section 1.4 of MAIA.
The Review Panel had regard to doubts expressed by the Court of Appeal, albeit in obiter remarks, regarding whether injury sustained via consequential surgery fell within the definition of “injury” in s 1.4.
The Review Panel concluded, however, that the Claimant’s right shoulder injury fell within the section 1.4 definition of “injury” given the causal connection between the lumbar spine injury, the cortisone injection, the left leg weakness and the fall, together with the fact that the fall caused the Claimant harm.
Conclusion
Given its conclusion that the right shoulder injury was an “injury” for the purpose of section 1.4, it followed that it was a non-threshold injury caused by the motor accident.
Why This Case is Important
The question of whether the Claimant can satisfy the threshold injury test – and become entitled to ongoing statutory benefits and common law damages – by relying, solely, on an injury sustained during consequential treatment remains unresolved.
The Court of Appeal in Mandoukos v Allianz Australia Insurance Limited [2024] NSWCA 71 expressed doubts on this question, at [99], as follows:
“In any event, even on the assumption that the removal of bone during the foraminotomy procedure could be a personal or bodily injury as defined in the Act (a question which, as set out at [54] above, it is unnecessary and inappropriate for this Court to determine) my provisional view is that that would be a “different” injury from the injury to Mr Mandoukos’ cervical spine sustained at the time of the motor accident. The foraminotomy procedure occurred some 18 months after the motor accident. It involved a mechanism, consensual surgical removal of bone, entirely separate from the impact of the motor accident. That is so even though it was performed by reason of Mr Mandoukos’ symptoms resulting from the motor accident. It is also of a different character from an assault or impact upon the body consequent upon the forces of the motor accident. Ultimately, however, if Mr Mandoukos seeks referral of a medical dispute as to whether the foraminotomy procedure has the consequence that the cervical spine injury he sustained in the motor accident is a minor injury, that question can be assessed by a medical assessor.”
The Review Panel in Miles sidestepped Mandoukos by stressing that the Claimant’s lumbar spine injury caused the need for cortisone treatment, which caused the left leg weakness, which caused the fall, which caused the right shoulder injury. A similar approach was recently adopted in Gibbin v AAI Ltd t/as GIO [2025] NSWPICMP 523, albeit without reference to Mandoukos.
The difficulty is that the same reasoning process could have been applied to Mr Mandoukos’ foraminotomy procedure. His accident caused a neck injury, which caused the need for a foraminotomy, which caused the removal of bone. Yet the Court of Appeal still expressed doubts over whether the removal of bone was an “injury” pursuant to section 1.4 of MAIA.
The distinction appears to be that the foraminotomy procedure which Mr Mandoukos underwent did not cause him any additional detriment or harm. It was designed to improve his physical condition. It followed that the removal of the bone was not an “injury“.
By contrast, the cortisone injection, in this claim, caused a fall which resulted in additional harm to the Claimant, by way of a rotator cuff tear.
Ultimately, however, there will still be confusion over whether injury sustained during consequential treatment can produce a non-threshold injury until a higher court is called upon to determine the issue.
If you would like to discuss this case note, please don’t hesitate to get in touch with CTP Practice Group Leader Peter Hunt today.
