Delayed-Onset Injury Causation in Workplace Rescuer Liability: Keane v Johnson & Johnson Vision Care

Introduction

This commentary examines the High Court of Ireland’s decision in Keane v Johnson & Johnson Vision Care (Ireland) [2025] IEHC 216, delivered by Mr Justice Paul Coffey on 1 April 2025. The plaintiff, Mark Keane, a process technician, intervened to rescue a colleague whose hand was trapped in heavy machinery. In doing so, he sustained finger and shoulder injuries and developed post-traumatic stress disorder (PTSD). Liability for the accident itself was admitted, but the central issue was whether the traumatic mechanism of rescue caused the plaintiff’s subsequent shoulder condition and resultant incapacity to work. The court’s analysis establishes a clear principle for linking delayed-onset injuries to an earlier traumatic event when the mechanism of injury, medical history, and progression of symptoms are consistent with causation.

Summary of the Judgment

The court found in favour of the plaintiff on causation and damages. Key conclusions include:

• Although the plaintiff did not report shoulder pain immediately, the mechanism of rescue (bearing heavy weight on the shoulder) and absence of prior shoulder pathology justified a causal link.
• Medical experts for the plaintiff—his GP, a pain specialist, and an orthopaedic surgeon—supported that delayed symptoms were masked by immobilisation and emerged as the shoulder was re-mobilised (“second-hit phenomenon”).
• The defendant’s arguments—late documentation of shoulder symptoms, absence of early complaints, strenuous cycling in 2020—were rejected as insufficient to break causation.
• The court awarded general damages of €135,000 and total special damages (past and future) of approximately €808,074.46, including loss of earnings, pension rights, medical expenses and future care.

Analysis

Precedents Cited

The judgment refers to several guiding authorities and texts:

• Book of Quantum (2016 edition)—used for assessing general damages for injuries occurring before 2019.
• Personal Injuries Guidelines (2021 edition)—provides ranges for psychiatric injuries (PTSD) in the absence of specific guidance in the Book of Quantum.
• Reddy v Bates [UK authority]—establishes deduction for vicissitudes of life when calculating future loss of earnings.

Although no reported Irish personal-injury cases on delayed symptom causation were cited, the judgment’s reasoning draws on established principles of causation, expert evaluation, and structured damage assessment.

Legal Reasoning

The court’s reasoning followed a structured approach:

1. Baseline and Absence of Prior Pathology
   The plaintiff had no recorded right shoulder symptoms before the accident. This clean pre-accident history established a baseline requiring explanation of subsequent shoulder pathology by an identifiable event.
2. Mechanism of Injury
   During the rescue, the plaintiff bore the full weight of a heavy machine part on his right shoulder for up to a minute. The court held that sustained, traumatic force is a credible cause for partial labral tear and sensitisation of shoulder structures.
3. Delayed Onset and “Second-Hit” Phenomenon
   The shoulder was immobilised in a sling for months due to the finger fracture. Immobilisation masked early symptoms. As movement resumed, arm and shoulder pain emerged. The court accepted expert evidence that re-mobilisation can precipitate symptoms in a pre-injured joint (“second-hit”).
4. Expert Evidence Weighed on Balance of Probabilities
   The plaintiff’s experts (GP Dr Boylan, pain specialist Prof. Harmon, orthopaedic surgeon Prof. Moran) consistently linked mechanism to injury. The defendant’s experts (Dr Quin, occupational physician Dr Madden) emphasised late symptom reporting, but the court found their interpretations less persuasive given the medical record as a whole.
5. Structured Damage Assessment
   Adhering to the two-stage approach in the Book of Quantum, each injury (finger, shoulder, PTSD) was assigned a fair value. Overlaps were adjusted to reach a proportionate total. Special damages for past and future loss of earnings, pension rights, care and medical treatment were calculated using actuarial methods with allowances for life’s vicissitudes under Reddy v Bates.

Impact

This decision reinforces important principles:

• Delayed-onset symptoms can be causally connected to an earlier traumatic event if the mechanism is clear, there is no alternative cause, and experts explain symptom progression.
• Immobilisation periods will not necessarily break causation; masking of symptoms is recognised.
• Comprehensive expert evidence and contemporaneous records remain crucial. Courts will evaluate the entire medical narrative rather than isolated entries.
• Employers admitting liability for an accident should anticipate claims for subsequent conditions once causation thresholds are met, even if symptoms emerge years later.

Future personal-injury litigation in Ireland may rely on Keane to establish causation for injuries with latent presentation, particularly in complex orthopedic or psychiatric claims.

Complex Concepts Simplified

• Chain of Causation – The legal link between the defendant’s wrong (machine safety failure) and the plaintiff’s injury (shoulder tear). It must be direct, without break from unrelated events.
• Second-Hit Phenomenon – An initial injury or trauma sensitises a body part. Later, when normal use resumes, underlying damage manifests clinically.
• Book of Quantum – A non-binding “tariff” published by the Personal Injuries Assessment Board to guide awards for physical injuries.
• General vs. Special Damages – “General” covers pain, suffering, loss of amenity. “Special” compensates quantifiable losses: earnings, medical expenses, care costs.
• Vicissitudes Deduction (Reddy v Bates) – A percentage reduction in calculated future losses to reflect the chance that the claimant’s earning capacity would have varied for reasons unconnected to the defendant’s wrongdoing.
• Actuarial Calculation – Using multipliers and discount rates to convert a stream of future earnings into a single present value lump sum.

Conclusion

Keane v Johnson & Johnson Vision Care establishes a pivotal precedent for recognising delayed-onset injuries in workplace accidents, especially for rescuers exposed to traumatic force. The High Court’s careful analysis of medical timelines, expert testimony, and established principles of causation confirms that lateness of symptom reporting does not bar recovery when credible explanation of progression exists. Employers and insurers should be alert to potential long-term claims following admitted accidents. This judgment strengthens the plaintiff’s position in complex personal-injury litigation and provides clear guidance on structuring causation arguments and quantifying multi-faceted damages.