Diagnostic Assessment — Right Ring Finger - Mallet Finger Avulsion Fracture
Example 1 of 1 · fictitious patient (Veteran AZ)
Diagnostic Assessment
Right Ring Finger - Mallet Finger Avulsion Fracture
BOP Code: 63 of 2024 (Fracture)
RH Code: 62 of 2024 (Fracture)
ADF History
Veteran AZ, date of birth 22 November 1980, Australian Army, Terminal Operator (cargo specialist), enlisted 07 February 2000, medically discharged 15 June 2018. Operational service: Timor-Leste, 02 June 2006 to 30 November 2006 (non-warlike); Middle East Area of Operations, 10 January 2016 to 25 July 2016 (warlike).
Occupational History
As a terminal operator the veteran loaded, secured and unloaded cargo on aircraft, ships, vehicles and in warehouses. The work involved repeated forceful gripping and tensioning of ratchet straps, chain binders and cargo nets, handling steel pallet locks and container twist-locks, and manual lifting of stores of 20 to 40 kilograms, often on night shifts. Fingers were frequently caught, crushed or struck by straps, locking bars and pallets.
Deployed cargo specialists worked long shifts at air and sea points of disembarkation in extreme heat, wearing long-sleeved uniforms and working largely indoors and at night, with limited access to hand surgery and hand therapy in theatre. The period also saw high rates of smoking among logistics personnel on deployment.
History
Veteran AZ, a terminal operator in the Australian Army with a malunited fracture of the right ring finger from 2012 and steroid-treated asthma, sustained a bony mallet avulsion fracture of the distal phalanx of the right ring finger on 14 March 2016 when a steel pallet locking bar struck the tip of the extended finger while he was securing cargo on warlike service in the Middle East. The fracture went on to non-union, confirmed on 12 July 2016, after splinting could not be maintained in theatre, and required open reduction and internal fixation on 10 August 2016.
Timeline
- 07 Feb 2000 — The veteran enlisted in the Australian Army and was allotted to the cargo specialist trade. The entry medical examination recorded normal hands, no previous fractures, no chronic illness and a non-smoker status. Weight 79 kg, height 1.78 m. "fit, hands normal, non-smoker"
- 19 Jun 2012 — During a field exercise his right ring finger was caught in a cargo net as a loaded net was lifted, fracturing the base of the middle phalanx at the proximal interphalangeal joint. The fracture was managed in buddy strapping and united in a malunited position, with 18 degrees of ulnar angulation and 10 degrees of rotation. Corrective osteotomy was not offered and he returned to cargo duties. He was also recorded as having taken up regular indoor rock climbing through unit adventure training. "PIP fracture, malunion, ulnar angulation"
- 11 Apr 2013 — A respiratory physician diagnosed severe eosinophilic asthma, recorded as having developed after prolonged exposure to dust and diesel exhaust in warehouses and on exercise. Inhaled therapy failed to control it, and maintenance prednisolone 12.5 mg daily was commenced and continued to 2017. His weight rose steadily on prednisolone. "eosinophilic asthma, prednisolone 12.5 mg daily"
- 09 Sep 2014 — At the garrison health centre, routine blood tests showed type 2 diabetes mellitus, attributed to long-term prednisolone and weight gain, with an HbA1c of 7.9 per cent. Metformin 1 g twice daily was commenced. Weight 117 kg, BMI 36.9. He was granted a medical waiver to deploy to a static logistics role. "type 2 diabetes, HbA1c 7.9"
- 14 Mar 2016 — On warlike service in the Middle East, while securing a loaded pallet on an aircraft loading platform at night, a steel pallet locking bar sprang closed and struck the tip of his extended right ring finger, forcing the distal interphalangeal joint into flexion. He was unable to extend the fingertip. X-ray at the role 2 facility showed a bony mallet injury with an avulsion fracture of the dorsal base of the distal phalanx. CT the next day showed that the avulsion had occurred through a pre-existing incomplete stress fracture with sclerotic margins. A stack splint was applied, to be worn continuously for eight weeks. "bony mallet, unable to extend"
- 25 Apr 2016 — At six-week review the medical officer recorded that the original splint had cracked in the heat on 02 April 2016, that no replacement in the correct size had been available for nine days, and that he had removed the splint for hand washing and duties because no waterproof alternative could be supplied. No hand therapist was available in theatre. He had resumed smoking about 20 cigarettes a day since the injury. X-ray showed no bridging callus and persisting displacement. "splint failed, no callus, smoking"
- 12 Jul 2016 — CT at four months showed established non-union of the avulsion fragment, with a 2 mm gap, sclerotic margins and 3 mm of fragment displacement. HbA1c was 8.6 per cent, serum 25-hydroxyvitamin D was 34 nmol/L and weight was 128 kg, BMI 40.4. He was still smoking 20 cigarettes a day. Return to Australia for surgery was arranged and he returned on 25 July 2016. "non-union, vitamin D 34, BMI 40.4"
- 10 Aug 2016 — A hand surgeon performed open reduction and internal fixation of the non-united fragment with a K-wire and extension block pinning. Dual-energy X-ray absorptiometry on 02 August 2016 had shown osteoporosis, with a lumbar spine T-score of minus 2.8, attributed to long-term prednisolone. Union was eventually achieved at five months after surgery, with a residual extensor lag of 20 degrees and early degenerative change at the distal interphalangeal joint. "ORIF non-union, osteoporosis T -2.8"
Symptoms
At onset the veteran had immediate pain, swelling and bruising over the back of the right ring fingertip, with a drooping fingertip and inability to actively straighten the distal interphalangeal joint. After the splint failed in April 2016 the pain, swelling and droop persisted, and the fragment did not unite.
He now reports a persistent 20-degree droop of the right ring fingertip, stiffness and aching of the distal interphalangeal joint in cold weather and with gripping, reduced grip strength, difficulty with fine tasks such as buttons and typing, and catching the fingertip on clothing and objects. Swan-neck posturing of the finger is present, aggravated by the older malunion at the proximal interphalangeal joint.
Imaging
- 19 Jun 2012 — X-ray right ring finger: "Intra-articular fracture of the base of the middle phalanx. Follow-up films on 30 July 2012 showed union with 18 degrees of ulnar angulation and rotational malalignment."
- 14 Mar 2016 — X-ray right ring finger: "Bony mallet injury: avulsion fracture of the dorsal base of the distal phalanx involving about 35 per cent of the articular surface, with 2 mm of displacement. Old malunited fracture of the middle phalanx base."
- 15 Mar 2016 — CT right ring finger: "Acute avulsion fracture of the dorsal base of the distal phalanx extending through a pre-existing incomplete stress fracture with sclerotic margins and periosteal reaction."
- 12 Jul 2016 — CT right ring finger: "Established non-union of the dorsal avulsion fragment with a 2 mm gap, sclerotic margins and 3 mm displacement."
- 02 Aug 2016 — Dual-energy X-ray absorptiometry: "Lumbar spine T-score minus 2.8, total hip T-score minus 2.5. Osteoporosis."
Onset Date
The most likely date of onset of this condition is 14 Mar 2016.
At that date the veteran was on warlike service in the Middle East Area of Operations as a terminal operator at an air point of disembarkation, securing loaded pallets on an aircraft loading platform on night shift. The fracture occurred when a steel pallet locking bar struck the tip of his extended right ring finger.
This date is appropriate because the injury is a discrete traumatic event recorded on the day at the role 2 facility, with X-ray the same night. His pre-deployment medical examination on 18 November 2015 recorded a full range of movement at the distal interphalangeal joint, apart from the known older malunion at the proximal interphalangeal joint.
For the physical force factor, the force was applied to the distal phalanx at the time of onset, on 14 Mar 2016. For the repetitive loading factor, the period before onset relied on runs from his arrival in theatre on 10 Jan 2016 to 14 Mar 2016, during which he tensioned about 300 to 400 straps and binders per shift, on top of years of similar cargo work and weekly rock climbing since 2012. For the abnormal force direction factor, the malunion of the middle phalanx with 18 degrees of ulnar angulation was present from July 2012 and at onset on 14 Mar 2016.
For the worsening factors, the period after onset runs from 14 Mar 2016 to the documented non-union on 12 Jul 2016. During that period he smoked about 20 cigarettes a day from mid-March 2016, and at the time of non-union he had type 2 diabetes (from September 2014), osteoporosis attributed to prednisolone taken since April 2013, a serum vitamin D level of 34 nmol/L and a BMI of 40.4. The splint failed on 02 Apr 2016 and could not be replaced for nine days.
1. What is the formal diagnosis of the condition claimed above?
The formal diagnosis is Right Ring Finger - Mallet Finger Avulsion Fracture (ICD-10-AM S62.63, fracture of the distal phalanx of another finger), under the Statements of Principles concerning fracture, Balance of Probabilities No. 63 of 2024 and Reasonable Hypothesis No. 62 of 2024.
A bony mallet finger is an avulsion fracture of the dorsal base of the distal phalanx at the insertion of the terminal extensor tendon. It is caused by forced flexion of the extended fingertip and results in a drooping fingertip with loss of active extension at the distal interphalangeal joint. Most heal with continuous extension splinting for six to eight weeks, but interruption of splinting, smoking, diabetes, poor bone quality and vitamin D deficiency increase the risk of non-union, persistent extensor lag, swan-neck deformity and post-traumatic arthritis.
The fracture occurred on 14 March 2016 on warlike service in the Middle East, through bone already weakened by a stress fracture and in a finger with an old malunion. It went on to non-union, confirmed on 12 July 2016, and required surgery on 10 August 2016.
2. For each diagnosis identified, please also provide the following dates:
When did the veteran first experience symptoms attributable to this condition?
14 March 2016.
When did the veteran first present to a health / medical provider for this condition?
14 March 2016.
When was the condition confirmed / formally diagnosed?
14 March 2016.
When did the veteran first present to you (or your practice) for this condition?
19 February 2025.
3. How was this diagnosis confirmed? i.e. what were the key symptoms and signs, investigation results, specialist opinions?
The diagnosis was confirmed by X-ray at the role 2 facility on 14 March 2016, which showed an avulsion fracture of the dorsal base of the distal phalanx of the right ring finger involving about 35 per cent of the articular surface, and by CT on 15 March 2016, which showed that the avulsion extended through a pre-existing incomplete stress fracture. This is a fracture as defined in the Statement of Principles.
Clinically there was a drooping fingertip with loss of active extension at the distal interphalangeal joint, swelling and bruising over the dorsal base of the distal phalanx. The clinical worsening, non-union, was confirmed by CT on 12 July 2016, and the condition required open reduction and internal fixation by a hand surgeon on 10 August 2016.
4. What do you consider to be the cause(s) of the condition in this veteran? Give consideration to constitutional and common risk factors, pre-existing injuries or diseases, and occupational or lifestyle risks, as well as direct causative mechanisms.
Legislation: the clinical onset of this condition was on 14 March 2016, after 1 July 2004, during continuous full-time service. This is a Military Rehabilitation and Compensation Act 2004 (MRCA) claim and the Statements of Principles apply. The Reasonable Hypothesis instrument applies to the veteran's warlike service in the Middle East Area of Operations from 10 January 2016 to 25 July 2016, where the fracture occurred and went on to non-union. The Balance of Probabilities instrument applies to his peacetime service, including the cargo work, the 2012 finger fracture, and the asthma and diabetes that developed in Australia.
Each factor must be related to the person's relevant service. Under the beneficial approach required by the legislation, the absence of documentation does not mean that an event or exposure did not occur: lack of evidence is not evidence of lack.
Balance of Probabilities — Statement of Principles concerning Fracture, No. 63 of 2024
Causative factors
Factor 9(1): having significant physical force applied to or through the affected bone at the time of clinical onset; — MET
- On 14 March 2016 a steel pallet locking bar sprang closed and struck the tip of the veteran's extended right ring finger, forcing the distal interphalangeal joint into flexion against the pull of the extensor tendon and avulsing the dorsal base of the distal phalanx. This was significant physical force applied to and through the affected bone at the moment of onset, during his cargo duties, recorded by the role 2 medical officer the same night.
Factor 9(2): for stress fracture only, having significant repetitive loading stress to the affected bone prior to clinical onset; — MET
- CT on 15 March 2016 showed that the avulsion extended through a pre-existing incomplete stress fracture of the dorsal base of the distal phalanx, with sclerotic margins and periosteal reaction. Before onset the veteran had applied significant repetitive loading stress to the fingertip as a cargo specialist since 2000, gripping and tensioning ratchet straps and chain binders with the fingertips crimped, about 300 to 400 times a shift in the warehouse and on aircraft loading, and by weekly crimp-grip rock climbing in unit adventure training from 2012.
Factor 9(3): for stress fracture only, having significant chronic repetitive loading stress to the affected bone due to abnormal force intensity or direction of application, at the time of clinical onset; — MET
- The malunited fracture of the base of the middle phalanx sustained during a field exercise on 19 June 2012 left the right ring finger with 18 degrees of ulnar angulation and 10 degrees of rotation, which was never corrected. As a result the extensor mechanism pulled obliquely across the distal phalanx, and every grip and strap-tensioning load was applied to the dorsal base of the distal phalanx in an abnormal direction. This chronic abnormal loading was present at onset on 14 March 2016 and accounts for the stress fracture seen on CT.
Worsening factors
Factor 9(4): smoking at least 5 cigarettes per day, or the equivalent thereof in other tobacco products, during treatment for fracture prior to fracture non-union; — MET
- The veteran resumed smoking after the injury and smoked about 20 cigarettes a day from mid-March 2016, recorded at review on 25 April 2016 and again on 12 July 2016, throughout the treatment period before the non-union was confirmed on 12 July 2016. Cheap tobacco and long night shifts on deployment contributed. Smoking impairs fracture healing by reducing blood flow and osteoblast activity.
Factor 9(5): having diabetes mellitus at the time of the fracture non-union; — MET
- Type 2 diabetes mellitus was diagnosed on 09 September 2014 with an HbA1c of 7.9 per cent, attributed to long-term prednisolone prescribed by Defence-funded specialists for asthma, and was treated with metformin. At the time of the non-union on 12 July 2016 the HbA1c was 8.6 per cent, reflecting poor control on a deployed diet. Diabetes impairs fracture healing.
Factor 9(6): inability to obtain appropriate clinical management for fracture before clinical worsening. — MET
- The fracture required continuous extension splinting for eight weeks. The original splint cracked in the heat on 02 April 2016, no replacement in the correct size was available for nine days, no waterproof splint could be supplied, and there was no hand therapist or hand surgeon in theatre, so the distal interphalangeal joint was repeatedly allowed to flex. Return to Australia for surgical assessment did not occur until 25 July 2016, after non-union was established on 12 July 2016. Under Brew v Repatriation Commission (1999) this is an inability to obtain appropriate clinical management before the clinical worsening.
Reasonable Hypothesis — Statement of Principles concerning Fracture, No. 62 of 2024
Causative factors
Factor 9(1): having significant physical force applied to or through the affected bone at the time of clinical onset; — MET
- On warlike service in the Middle East on 14 March 2016 a steel pallet locking bar struck the tip of the veteran's extended right ring finger while he was securing cargo on an aircraft loading platform, forcibly flexing the distal interphalangeal joint and avulsing the dorsal base of the distal phalanx. The force was applied at the time of onset during operational duties.
Factor 9(2): for stress fracture only, having significant repetitive loading stress to the affected bone prior to clinical onset; — MET
- From his arrival in theatre on 10 January 2016 to the injury on 14 March 2016 the veteran worked twelve-hour night shifts loading and securing aircraft pallets, tensioning about 300 to 400 ratchet straps and binders per shift with the fingertips crimped. CT on 15 March 2016 showed a pre-existing incomplete stress fracture at the dorsal base of the distal phalanx, through which the avulsion occurred. The repetitive loading was imposed by his warlike service.
Factor 9(3): for stress fracture only, having significant chronic repetitive loading stress to the affected bone due to abnormal force intensity or direction of application, at the time of clinical onset; — MET
- The uncorrected 18-degree ulnar angulation and rotational malunion of the middle phalanx from 2012 directed the strap-tensioning loads obliquely through the dorsal base of the distal phalanx. This abnormal direction of loading was present throughout his cargo work on warlike service in the Middle East and at onset on 14 March 2016.
Worsening factors
Factor 9(4): smoking at least 5 cigarettes per day, or the equivalent thereof in other tobacco products, during treatment for fracture prior to fracture non-union; — MET
- On warlike service in the Middle East the veteran smoked about 20 cigarettes a day throughout the treatment of the fracture from mid-March 2016 to the confirmation of non-union on 12 July 2016, as recorded on 25 April and 12 July 2016. He had resumed smoking under the stress and long night shifts of the deployment.
Factor 9(5): having diabetes mellitus at the time of the fracture non-union; — MET
- The veteran had type 2 diabetes mellitus, diagnosed on 09 September 2014, at the time of the non-union on 12 July 2016, when his HbA1c was 8.6 per cent. Control deteriorated on warlike service because of irregular meals on night shift and limited access to his usual diet and monitoring.
Factor 9(6): having osteoporosis at the time of the fracture non-union; — MET
- Dual-energy X-ray absorptiometry on 02 August 2016 showed osteoporosis, with a lumbar spine T-score of minus 2.8 and a total hip T-score of minus 2.5, three weeks after the non-union was confirmed. The osteoporosis was caused by maintenance prednisolone 12.5 mg daily taken continuously since 11 April 2013 for service-related asthma, and was therefore present at the time of the non-union on 12 July 2016, while he was on warlike service.
Factor 9(7): having vitamin D deficiency, with a serum 25(OH)D level of less than 50 nanomoles per litre at the time of the fracture non-union; — MET
- On 12 July 2016, the day the non-union was confirmed, the veteran's serum 25-hydroxyvitamin D level was 34 nmol/L. The deficiency arose on warlike service from six months of night shifts, indoor warehouse work and full-length uniform, with little sun exposure, compounded by long-term prednisolone.
Factor 9(8): having a Body Mass Index (BMI) of 40 or greater at the time of the fracture non-union; — MET
- On 12 July 2016, at the time of the non-union, the veteran weighed 128 kg at a height of 1.78 m, a BMI of 40.4. His weight had risen from 79 kg at enlistment on long-term prednisolone for service-related asthma and with reduced activity, and increased further on deployment.
Factor 9(9): inability to obtain appropriate clinical management for fracture before clinical worsening. — MET
- On warlike service the veteran could not obtain a replacement splint for nine days after the original cracked on 02 April 2016, could not obtain a waterproof splint, and had no access to a hand therapist or hand surgeon. Operational demands delayed his return to Australia until 25 July 2016, after the non-union was established on 12 July 2016. These operational constraints amount to an inability to obtain appropriate clinical management before the clinical worsening.
The % contribution of the causes is 100% and significant.
Sequelae
The non-union and its surgical treatment have left a persistent 20-degree extensor lag, swan-neck posturing and early post-traumatic osteoarthritis of the distal interphalangeal joint of the right ring finger, with reduced grip strength. These are sequelae of the accepted fracture.
Unintended Consequence
Met. The osteoporosis, type 2 diabetes and weight gain that contributed to the non-union are unintended consequences of long-term prednisolone prescribed and paid for by the Commonwealth for the veteran's service-related asthma from April 2013 (section 6A of the DRCA and the equivalent provisions of the MRCA).
Inability to Attain Appropriate Medical Management
MET. A bony mallet fracture depends on uninterrupted extension splinting. On warlike service the veteran's splint cracked on 02 April 2016 and could not be replaced for nine days, no waterproof splint was available, and there was no hand therapist or hand surgeon in theatre, so he removed the splint for hygiene and duties. His return to Australia for surgical review was delayed by operational demands until 25 July 2016, after non-union had been confirmed on 12 July 2016. Applying the objective and subjective tests in Brew v Repatriation Commission (Full Federal Court, 10 September 1999, Merkel J), operational constraints that prevent the prescribed treatment amount to an inability to obtain appropriate clinical management, and this contributed to the non-union.
5. Please provide a Health Summary and a medication / prescribing history.
See attached report.
References
- 07 Feb 2000, Entry medical examination, Army recruiting medical officer
- 19 Jun 2012, X-ray right ring finger and treatment record, Radiologist and Medical Officer
- 30 Jul 2012, X-ray right ring finger, Radiologist
- 11 Apr 2013, Specialist letter, Respiratory physician
- 09 Sep 2014, Outpatient health record and pathology, Medical Officer, Garrison health centre
- 18 Nov 2015, Pre-deployment medical examination, Medical Officer
- 14 Mar 2016, Role 2 treatment record and X-ray, Medical officer, Middle East
- 15 Mar 2016, CT right ring finger, Radiologist
- 25 Apr 2016, Six-week fracture review and X-ray, Medical officer, Middle East
- 12 Jul 2016, CT right ring finger and pathology, Radiologist and Medical officer
- 02 Aug 2016, Dual-energy X-ray absorptiometry report, Radiologist
- 10 Aug 2016, Operation report, Hand surgeon
- Statement of Principles concerning Fracture (Balance of Probabilities) No. 63 of 2024, Repatriation Medical Authority
- Statement of Principles concerning Fracture (Reasonable Hypothesis) No. 62 of 2024, Repatriation Medical Authority
