Statement of Principles concerning Morton metatarsalgia (Reasonable Hypothesis) (No. 77 of 2019)

This Statement of Principles (SoP) is a legislative instrument made under subsection 196B(2) of the Veterans’ Entitlements Act 1986 (VEA) by the Repatriation Medical Authority. It creates a framework for determining whether Morton metatarsalgia (also known as Morton neuroma) can be connected, by a reasonable hypothesis, to certain kinds of military service rendered by veterans and members covered by the VEA or the Military Rehabilitation and Compensation Act 2004 (MRCA). The instrument sets out the minimum factors that must exist before it can be said that a reasonable hypothesis has been raised linking the condition (or death from it) to the circumstances of a person’s relevant service. It repeals and replaces the earlier Statement of Principles concerning Morton’s metatarsalgia No. 92 of 2010; it commences on 23 September 2019.

Mechanically, the SoP defines the condition narrowly: an entrapment or irritation of the interdigital plantar nerve between the metatarsal heads causing an acquired neuropathy, and explicitly excludes peripheral neuropathy. It assigns the ICD‑10‑AM code G57.6 but makes clear the definition in the instrument governs. It then lists eleven factors (section 9), five that apply to the clinical onset of the condition and five parallel factors that apply to its clinical worsening, plus a sixth factor (inability to obtain appropriate clinical management) that applies only to worsening. Each factor must be related to the person’s relevant service. The SoP also defines “terminal event” and “specified list of deformities of the foot” in its dictionary, and provides a mechanism (section 11) for cross-referencing other SoPs where a factor refers to an injury or disease covered by another such instrument.

The SoP does not itself grant or deny compensation; it operates as the evidentiary standard for decision-makers. Under the VEA and MRCA, when a claim for a service-related condition is made, the decision-maker must apply the relevant SoP to decide whether the material raises a reasonable hypothesis connecting the condition to service. This SoP therefore shapes the evidence required from veterans, clinicians and advocates. Its effect is to channel claims into defined causal pathways - footwear, injury, surgery, structural deformities, inflammatory arthritis, or inability to obtain clinical management - and to require those factors to meet specific temporal and quantitative thresholds (e.g., at least one year of compressive footwear worn at least four hours per day on more days than not).

Reasonable hypothesis. This is the central legal standard. Under sections 120 and 120A of the VEA, a reasonable hypothesis is one that is consistent with the known medical facts and that points to a causal relationship between service and the condition. The SoP defines the minimum content of such a hypothesis for Morton metatarsalgia. It is a lower threshold than the civil standard of proof, but it must be more than a mere possibility. The SoP embodies the Repatriation Medical Authority’s conclusion that sound medical-scientific evidence supports the listed factors as sufficient to raise that hypothesis.

Clinical onset and clinical worsening. The SoP distinguishes between the first appearance of the condition (onset) and a material worsening after it has already been contracted. Factors 1-5 address onset; factors 6-11 address worsening. Notably, factor 11 (inability to obtain appropriate clinical management) applies only to worsening, not onset. This means a claimant cannot argue a lack of clinical management caused the condition to arise, only that it aggravated an existing condition. The distinction is important because the “clinical worsening” factors apply only where the condition was suffered or contracted before or during (but did not arise out of) the person’s relevant service (section 10(2)).

Relevant service. This is defined by reference to service types under the VEA (operational, peacekeeping, hazardous, British nuclear test defence) and the MRCA (warlike, non-warlike). The SoP does not apply to peacetime service under the VEA (which is not “relevant service”); different rules apply for those claims, often under a “balance of probabilities” standard. This means the SoP’s strict factor list applies only to the highest categories of service, where the reasonable hypothesis standard is used.

Morton metatarsalgia - defined condition. The definition is specific: entrapment or irritation of the interdigital plantar nerve between the metatarsal heads causing an acquired neuropathy. The exclusion of peripheral neuropathy is critical. A veteran with forefoot pain from a systemic neuropathy (e.g., diabetic neuropathy) cannot rely on this SoP; the condition must be a localised nerve entrapment. The ICD-10-AM code is G57.6, but the text of the definition controls.

Factors for onset. The five onset factors are: (1) compressive or high-heeled footwear for at least four hours per day on more days than not for at least one year before onset; (2) injury to the foot damaging or compressing the affected nerve within one year before onset; (3) surgery to the foot damaging or compressing the nerve within one year before onset; (4) a specified foot deformity (enumerated list: claw toes, fracture deformity, equinus, hallux rigidus, hallux valgus, hammer toes, pes cavus, pes planus) at the time of onset; (5) inflammatory arthritis at the time of onset. The deformity and inflammatory arthritis must “damage or compress the interdigital plantar nerve within the affected intermetatarsal space”, not merely be present. This causal element is often overlooked.

The SoP directly affects any person who has rendered “relevant service” as defined - operational service under the VEA, peacekeeping service, hazardous service, British nuclear test defence service, or warlike or non-warlike service under the MRCA - and who suffers from Morton metatarsalgia or dies from it. This includes current and former members of the Australian Defence Force, Peacekeeping Forces, and certain civilian participants in British nuclear tests. It also affects the dependants of such persons who claim in relation to the death from the condition.

Indirectly, the SoP affects decision-makers at the Department of Veterans’ Affairs and the Military Rehabilitation and Compensation Commission, who must apply it when assessing eligibility for disability compensation payments or other benefits. Veterans’ advocates, lawyers, and medical practitioners (particularly podiatrists, orthopaedic surgeons, neurologists and general practitioners) are affected because they must gather and present evidence that fits the SoP’s factors. The SoP creates a regulatory hurdle: unless one of the listed factors is present and can be related to service, a claim will fail regardless of the clinical severity of the condition.

The SoP also affects the Repatriation Medical Authority itself, which is responsible for determining and reviewing these instruments. The replacement of the 2010 SoP with this 2019 version changes the evidentiary requirements for claims made or pending after 23 September 2019. Any decision on a claim for Morton metatarsalgia must be made in accordance with this SoP if the claim is subject to section 120A of the VEA or section 338 of the MRCA. Existing decisions made under the previous SoP are not automatically reopened, but new claims or applications for review are bound by the current instrument.

Crucially, the SoP does not affect persons whose Morton metatarsalgia arises from peacetime service under the VEA (e.g., peacetime service before 1994 or certain peacekeeping service later classified as peacetime). For those claims, the applicable standard is reasonable satisfaction (balance of probabilities) and there is no mandatory SoP; the decision-maker may have regard to the SoP as expert opinion but is not bound by it. This creates a bifurcation: veterans covered by the SoP have a more rigid but also potentially clearer pathway to establishing connection, while others have broader discretion but less predictability.

The SoP itself does not impose positive duties on individuals, but it establishes obligations for the decision-maker. When a claim is made under the VEA or MRCA that engages this SoP, the decision-maker must consider whether at least one of the factors in section 9 exists. If so, and if that factor is related to the person’s relevant service, then the decision-maker must find that a reasonable hypothesis exists linking Morton metatarsalgia to service. At that point, the burden shifts to the decision-maker to disprove the hypothesis beyond reasonable doubt (under the VEA) or to decide the matter on the balance of probabilities (under the MRCA). The SoP therefore confers a right on the claimant to have the claim assessed through this structured lens, rather than a free-form medical inquiry.

Claimants have the right to present evidence of any of the factors, including medical records, specialist reports, and lay evidence about footwear habits, injuries, surgeries, or deformities. The SoP does not require expert evidence, but in practice meeting factors such as “inflammatory arthritis which damages or compresses the interdigital plantar nerve” will usually require a medical diagnosis. The right to use factor 11 (inability to obtain appropriate clinical management) is significant because it does not require a temporal connection to service for the initial condition, only that the inability to get proper care (due to service circumstances) caused worsening.

Another right implicit in the SoP is the ability to rely on cross-referenced SoPs. Under section 11, if a factor refers to an injury or disease that is itself the subject of a SoP (e.g., “inflammatory arthritis” might be a condition with its own SoP), then the claimant can use that SoP’s factors to establish the existence of that condition for the purposes of the Morton metatarsalgia SoP. This is an important right because it incorporates the established causal pathways for the underlying condition rather than requiring separate proof of causation from scratch.

The duty to “relate” the factor to service (section 10(1)) is imposed on the decision-maker but also on the claimant to produce evidence of service connection. For example, a veteran who wore steel-capped boots on a navy ship for years can relate that footwear to service, but a veteran who wore high-heeled shoes only off-duty may struggle unless the boots or uniform footwear themselves were high-heeled or compressive. The duty of consistency is also imposed on the Repatriation Medical Authority: the SoP must be grounded in sound medical-scientific evidence, and the Authority must review and update it periodically.

This SoP contains no penalty provisions. It is an evidentiary instrument, not a penal one. The consequences of non-compliance are to the claimant, not punishment: if the claimant fails to establish any factor, the claim for Morton metatarsalgia will be refused. There is no penalty for putting forward a claim that does not meet the SoP; it is simply unsuccessful.

However, the VEA and MRCA contain penalty provisions for making false statements or providing false documents in support of a claim (see, for example, section 211 of the VEA, which creates offences for obtaining financial advantage by false statements). Those penalties could be triggered if a claimant fabricates evidence to meet a SoP factor. But those are offences under the parent Act, not under this instrument.

Enforcement of the SoP itself is through the administrative review process. If a decision-maker erroneously applies the SoP (e.g., misinterprets “more days than not” or overlooks a factor), the claimant can seek merits review in the Veterans’ Review Board and then in the Administrative Appeals Tribunal. The AAT can substitute its own decision, but it must apply the SoP as a legislative instrument. A decision-maker who intentionally disregards the SoP could be found to have committed an error of law, and a court could set aside the decision. Still, this is a civil administrative enforcement mechanism, not a penal one.

The Repatriation Medical Authority has no enforcement role in individual claims. Its duty is to maintain the SoP and ensure it reflects current medical evidence. It does not police whether veterans actually wear compressive footwear; that is left to the claims process. The only “enforcement” that could be described is the requirement that the SoP be published on the Federal Register of Legislation and that its terms be complied with by delegates. A failure by the Authority itself to make a valid instrument could be challenged by judicial review, but that is rare.

The SoP is made under subsection 196B(2) of the VEA. It is a legislative instrument within the meaning of the Legislation Act 2003. It operates within the broader framework of the VEA and the MRCA. Its primary interaction is with sections 120, 120A and 120B of the VEA, which establish the “reasonable hypothesis” standard and require decision-makers to have regard to this SoP. For MRCA claims, the interaction is via section 338 of that Act, which similarly requires SoPs to be used for the reasonable hypothesis standard.

The SoP also interacts with other SoPs through section 11. If a factor in this SoP refers to an injury or disease that is the subject of another SoP (for example, if “inflammatory arthritis” is itself a defined condition with a separate SoP), then that other SoP’s factors apply as if they were part of this instrument. This creates a chain: a veteran may need to satisfy not only the Morton metatarsalgia factors but also the factors for the underlying rheumatoid arthritis if that is the only way to establish the arthritis damaged the nerve. This can increase the evidentiary burden significantly.

The SoP refers to the ICD-10-AM classification for coding purposes but expressly states that the definition in the instrument overrides the code. This prevents the ambiguity that could arise if the ICD coding changed over time. The Tenth Edition (2017) is specified, which means the SoP is tied to that revision; any future revision of ICD-10-AM would not automatically update this SoP; an amendment or new SoP would be needed.

The SoP does not interact with state workers’ compensation laws, motor accident compensation, or private health insurance, as it is confined to the federal veterans’ and military compensation system. It also does not override the requirement that a condition be diagnosed by a qualified medical practitioner. For example, if a veteran has forefoot pain but no formal diagnosis of Morton metatarsalgia, the SoP cannot be applied until a diagnosis confirming the specified definition is made.

Another important interaction is with the statutory time limits for claiming compensation. The SoP does not extend or modify those limits; it only provides the test for connection once a claim is lodged. However, the “inability to obtain appropriate clinical management” factor may interact with the requirement that the condition was already suffered or contracted before or during service, because it applies only to worsening. So a veteran who first developed Morton metatarsalgia after service cannot use factor 11 unless they can show the condition existed before or during service and then worsened.

This SoP (No. 77 of 2019) is the second version concerning Morton metatarsalgia. It repeals the earlier instrument, the Statement of Principles concerning Morton’s metatarsalgia No. 92 of 2010 (F2010L02848). The exact differences between the 2010 and 2019 versions are not detailed in this source, but the 2019 instrument updates the definition (now excludes “peripheral neuropathy”), updates the ICD-10-AM edition to the Tenth Edition 2017, and changes the list of factors. Notably, the 2010 version had a factor for “wearing footwear which compresses the forefoot or has a high heel” with the same duration threshold; the 2019 version adds “increases the pressure on the ball of the affected foot”. The 2019 version also explicitly includes the “specified list of deformities of the foot” as a defined term, whereas the 2010 version may have listed deformities differently. The 2019 version adds “equinus deformity” to the list and includes “inflammatory arthritis” as a separate factor for both onset and worsening, which may have been absent or narrower in 2010.

The instrument was made on 23 August 2019 and commenced on 23 September 2019 (one month later, standard for SoPs). There is no indication of any intermediate amending instruments. The source gives no further amendment history. SoPs are generally reviewed by the Repatriation Medical Authority every few years; the 2010 version was in force for nearly nine years before replacement. No sunsetting date is mentioned; it continues in force until repealed or amended.

The source does not name any specific litigation concerning this SoP or its predecessor. However, it is well known that Statements of Principles are frequently the subject of appeals in the Administrative Appeals Tribunal and the Federal Court. Claimants often contest the application of factors, the interpretation of “clinical worsening”, or the sufficiency of evidence. The scope of “inability to obtain appropriate clinical management” has been litigated in relation to other SoPs. Because the source provides no cases, this section cannot name them. An analyst should note that the SoP is likely to have been considered in many AAT and Federal Court decisions, but listing them would require external research beyond the source. The Repatriation Medical Authority’s determination that “sound medical-scientific evidence” supports the factors is itself a finding that could theoretically be challenged on jurisdictional grounds, though such challenges are rare. The instrument is made under s 196B(2) and is thus subject to judicial review under the Administrative Decisions (Judicial Review) Act 1977 or the High Court’s original jurisdiction, but no such challenges are recorded in this source.

A prime gotcha is the “more days than not” threshold for the footwear factor. This means the veteran must have worn the compressive or high-heeled footwear on more than half the days in the year before clinical onset or worsening. Intermittent use - even four hours daily but only on weekends - would likely fail. A strict record may be required; self-reporting alone may be challenged. Similarly, “at least four hours per day” may be cumulative; if the veteran wore dress shoes for two hours in the morning and two hours in the evening, that satisfies the threshold, but the burden of proof lies with the claimant.

Another trap involves the phrase “specified list of deformities of the foot”. It is a closed list. For instance, “pes planus” (flat feet) is included, but not “pronation” unless it leads to pes planus. A veteran with cavovarus foot (combination of pes cavus and varus) may have a condition that is not explicitly listed. The deformity must also “damage or compress the interdigital plantar nerve within the affected intermetatarsal space”. Medical evidence is needed to show that the specific deformity caused compression at the specific intermetatarsal space, not just that the deformity and Morton metatarsalgia coexist.

The factor for “injury to the foot” requires the injury to “damage or compress the interdigital plantar nerve”. A blunt trauma that causes swelling and secondary compression may qualify, but the injury must be within one year before onset or worsening. This is a strict temporal window. A remote fracture that healed without direct nerve compression years earlier will not suffice.

Factor 11 (inability to obtain appropriate clinical management) is often misunderstood. It applies only to worsening, not onset. It also requires that the inability be related to service. If the veteran simply chose not to seek treatment for personal reasons, that is not inability related to service. The term “appropriate clinical management” is not defined, leaving room for argument about what management is appropriate - podiatry, orthotics, injections, surgery? The inability must also cause the worsening; mere delay in treatment is not automatically a worsening factor.

Another subtlety: the SoP’s definition excludes peripheral neuropathy. If a veteran has systemic conditions like diabetes or hypothyroidism that cause peripheral neuropathy, the diagnosis of Morton metatarsalgia must be clearly distinguished from the systemic neuropathy. ICD coding may be ambiguous; the decision-maker should look at the clinical notes.

The “clinical worsening” factors (6-10) require that the person already had Morton metatarsalgia before or during service, but it did not arise out of service (section 10(2)). This creates a difficult line: if the condition first appeared during service but is not related to service, the factor must be for worsening, not onset. If a veteran developed Morton metatarsalgia during a posting but claims it is due to service, they must use the onset factors. If they instead argue the condition existed before service and was worsened by service, they need worsening factors. Choosing the wrong pathway can lead to a failed claim.

For a claimant seeking to establish that Morton metatarsalgia is related to relevant service, the first step is to ensure a diagnosis that meets the definition: entrapment or irritation of the interdigital plantar nerve between metatarsal heads, not peripheral neuropathy. A neurologist or podiatrist should specify the intermetatarsal space and confirm the diagnosis with imaging (ultrasound or MRI) if needed.

Next, identify which factor(s) apply. The most common factor is factor 1 for onset or factor 6 for worsening: footwear. The veteran should obtain evidence of the footwear worn - ideally contemporaneous records (e.g., shoe purchase dates, workplace uniform policies, photos). A written statement detailing the type of footwear, how many hours per day it was worn, and that it compressed the forefoot or increased pressure on the ball of the foot, for at least four hours per day on more days than not, for at least one year before onset (or worsening). Diary entries, family corroboration, and evidence from the service unit about footwear requirements are valuable.

For factors 2 and 7 (injury), the veteran needs medical records of a foot injury within one year before onset or worsening, with documentation that the injury damaged or compressed the nerve. Ankle fractures, metatarsal fractures, or blunt trauma to the forefoot may qualify. Surgery (factors 3 and 8) requires operative notes or discharge summaries showing surgery on the foot within one year, and evidence that the nerve was damaged or compressed during the operation.

For factors 4 and 9 (deformity), a medical report confirming one of the eight listed deformities and explaining how it causes compression of the nerve in the affected intermetatarsal space is essential. X-rays or weight-bearing scans may be needed. For factors 5 and 10 (inflammatory arthritis), a rheumatologist’s diagnosis of an inflammatory arthritis (e.g., rheumatoid arthritis, psoriatic arthritis, gout) and a link to nerve compression is required. If the arthritis condition is itself covered by a SoP, the claimant must also meet that SoP’s factors.

Factor 11 (inability to obtain appropriate clinical management) requires evidence that the veteran could not access appropriate treatment due to service circumstances - for example, a posting to a remote location without podiatry services, or a combat situation that prevented medical follow-up. A report from a treating practitioner outlining the standard of care and why the veteran’s inability (not choice) led to worsening.

All factors must be related to the person’s relevant service. The claimant should document how the factor connects to service: for instance, military boots causing compression, or an injury during a training exercise, or a service-related deformity such as fracture from a parachute landing. The claim should be lodged with the Department of Veterans’ Affairs or the Military Rehabilitation and Compensation Commission, with the supporting evidence. If the claim is refused, the veteran can seek review, where the SoP factors remain the central test. Engaging a specialist veterans’ advocate or lawyer experienced with SoPs is advisable, as the interaction between multiple SoPs and the strict temporal thresholds are often decisive.