When treatment for a work injury leads to another condition

Identify the injury and authorised treatment

Keep the insurer acceptance, referral, treatment approval and consent records for the original injury. They show why medication, surgery, hospital care or rehabilitation was undertaken.

Where treatment proceeded without written approval, the liability question may include whether the treatment was reasonably necessary as well as whether the later condition arose from it.

Later diagnoses that require separate attention

The treatment consequence should be described precisely. This principle page covers:

• clinically documented medication side effects or interactions
• surgical complications, including postoperative infection or wound problems
• nerve injury following surgery or another procedure
• scar sensitivity, restriction or skin-graft consequences
• a new physical impairment caused by treatment rather than the original accident

What a medical opinion should address

The opinion should identify the later diagnosis, explain its temporal and medical relationship to the treatment, and consider known risks, prior conditions and other possible causes. A sequence of “surgery, then symptoms” may be relevant but is not a complete causation analysis.

For medication, the prescriber may need to identify the drug, dose, duration, reported adverse effect and response to dose change or cessation. For infection or nerve injury, operative, hospital and specialist records are usually central.

The treatment timeline matters

Set out the treatment request and approval, medication commencement or procedure date, discharge, first report of the later symptoms, tests, diagnosis and subsequent treatment. Keep emergency or readmission records where relevant.

A later diagnosis may not be made immediately. The records should still show how the symptoms evolved and whether the treating team investigated alternative explanations.

Separate correction of the complication from the original care

The worker may need antibiotics, revision surgery, nerve testing, scar management, psychological support or medication review. Each request should identify the condition being treated and its expected functional benefit.

A request for further surgery should not assume the earlier complication proves the next procedure is reasonable. The specialist should address alternatives, risks and the link to the accepted injury and treatment.

Acceptance of the original injury is not the whole answer

An insurer can accept the original shoulder, spine or knee injury but dispute a postoperative infection, medication effect or nerve injury. Check whether the later diagnosis appears in the written acceptance or has received a separate liability decision.

SIRA Standard S13 expects prompt investigation where an additional or consequential condition is identified on a certificate of capacity. A treatment invoice being paid does not necessarily define the accepted scope of the claim.

Common treatment-consequence disputes

The insurer may argue that:

• the reported effect is a known symptom of the original injury rather than a new diagnosis
• infection or nerve symptoms are unrelated to the procedure
• the medication was prescribed for a non-work condition or the adverse effect is unsupported
• the scar or graft causes no measurable functional impairment
• further treatment is not reasonably necessary or addresses a condition not accepted

How treatment-related impairment is handled

NSW Guideline paragraph 1.31 provides that a further physical impairment resulting from treatment is assessed under the appropriate body-system method and combined with the original impairment where permitted. This does not mean every complication produces a separate percentage.

The assessor must avoid counting the same motion loss, nerve deficit, scar restriction or organ effect twice. Secondary psychological impairment is treated differently and is not assessed for WPI.

Effect on treatment and weekly payments

A complication may extend incapacity, change restrictions or create a new treatment need. Certificates should identify which condition prevents work and why the proposed duties are not sustainable.

Weekly payments and treatment remain subject to the applicable NSW rules and the insurer’s liability decisions. A complication does not automatically extend or restore an entitlement.

Evidence checklist

Keep a complete treatment record, including:

• original acceptance, referrals, approvals and treatment requests
• medication chart, pharmacy history and adverse-effect reports
• operative report, anaesthetic record, discharge summary and consent material
• pathology, culture, imaging, EMG/NCS or specialist test results where relevant
• hospital readmission, wound, infection, nerve or scar-management records
• certificates of capacity separating original and later restrictions