Diagnostic Assessment — Right Knee - Anterior Cruciate Ligament Sprain
Example 1 of 1 · fictitious patient (Veteran DZ)
Diagnostic Assessment
Right Knee - Anterior Cruciate Ligament Sprain
BOP Code: 28 of 2020 (Sprain and Strain)
RH Code: 27 of 2020 (Sprain and Strain)
ADF History
Veteran DZ, date of birth 11 February 1983, Royal Australian Air Force, Airfield Defence Guard, enlisted 08 July 2002, medically discharged 19 March 2015. Operational service: East Timor, 12 June 2006 to 15 December 2006 (non-warlike); Afghanistan, 02 April 2012 to 26 July 2012 (warlike, returned early after injury).
Occupational History
As an airfield defence guard the veteran conducted foot and vehicle patrols of airfield perimeters and forward bases carrying body armour, weapon, ammunition and communications equipment of 30 to 40 kilograms, often at night and over broken ground, drainage ditches and irrigation channels. Duties included repeatedly mounting and dismounting from the trays and tailgates of trucks and protected vehicles, quick reaction force drills and close quarter combat training.
Ground defence personnel have a high rate of knee ligament injury from landing awkwardly under load, twisting on uneven ground and sudden changes of direction, and of hamstring and calf muscle strain from sprinting and jumping with heavy equipment. On deployment, access to imaging, physiotherapy and orthopaedic review is limited.
History
Veteran DZ, an airfield defence guard in the Royal Australian Air Force, sprained the anterior cruciate ligament of his right knee, with a high-grade partial tear and a medial hamstring strain, when he jumped from the tailgate of a truck under load on non-warlike service in East Timor on 21 September 2006. The sprain worsened to a complete rupture when he fell into an irrigation ditch on warlike service in Afghanistan on 08 July 2012, and he required reconstruction.
Timeline
- 14 Mar 2006 — At his pre-deployment medical the veteran reported no knee symptoms. Examination of both knees was normal, with negative Lachman, anterior drawer and pivot shift tests and full range of movement. He completed the pre-deployment fitness assessment, including a loaded march, without difficulty. "knees normal, Lachman negative"
- 21 Sep 2006 — On non-warlike service in East Timor, during a night response to civil unrest, the veteran jumped about 1.2 m from the tailgate of a truck carrying about 30 kg and landed with his right foot on the edge of a kerb. His knee gave way into valgus and internal rotation and he felt a pop, together with a sharp pain in the back of the thigh as he tried to stop himself falling. The knee swelled within two hours. The medical officer at the field clinic found a tense effusion, a positive Lachman test with a soft endpoint and tenderness over the medial hamstring. "R knee pop, effusion, Lachman positive"
- 22 Sep 2006 — Radiographs at the field hospital showed a moderate effusion with no fracture. No MRI or physiotherapy was available in theatre. The veteran was given a hinged brace and crutches for one week, then returned to patrol duties with a brace, with orthopaedic review deferred until the end of the deployment. "no fracture, MRI not available"
- 20 Dec 2006 — MRI of the right knee after return to Australia showed a high-grade partial tear of the anterior cruciate ligament, a grade 1 sprain of the medial collateral ligament and a healing grade 2 strain of the semimembranosus at the musculotendinous junction. An orthopaedic surgeon recommended non-operative management with supervised rehabilitation. "high-grade partial ACL tear"
- 19 Jun 2007 — After six months of supervised rehabilitation at the base physiotherapy department, including closed-chain strengthening, proprioceptive training and a graded return to running, the veteran was reviewed by the orthopaedic surgeon. The right knee had a grade 1 to 2 Lachman test with a firm but delayed endpoint, no effusion and hamstring strength within 10 per cent of the left. He was returned to unrestricted duties, with advice that a further pivoting injury could complete the tear. "return to duties, residual laxity"
- 16 Nov 2011 — At a physiotherapy review before deployment the right knee had a grade 1 Lachman test with a firm endpoint, a negative pivot shift and full strength on dynamometry. He reported no giving way in the previous four years and had completed all fitness and field requirements. He was assessed as fit to deploy. "grade 1 Lachman, firm endpoint"
- 08 Jul 2012 — On warlike service in Afghanistan, during a night security patrol carrying about 40 kg, the veteran slipped down the bank of an irrigation ditch and his right knee pivoted under him with the foot fixed in mud. He felt a loud pop, the knee gave way and he had sudden pain in the back of the right thigh as he scrambled up the bank. At the role 2 facility there was a large effusion, a grade 3 Lachman test with no endpoint, a positive pivot shift and bruising over the medial hamstring. "R knee gave way, grade 3 Lachman"
- 30 Jul 2012 — After aeromedical return to Australia on 26 July 2012, MRI showed a complete rupture of the anterior cruciate ligament, a bone bruise of the lateral femoral condyle and posterolateral tibial plateau, and a grade 2 re-tear of the semimembranosus musculotendinous junction. On 18 October 2012 an orthopaedic surgeon performed an anterior cruciate ligament reconstruction with a patellar tendon graft. He did not regain the fitness required for his trade and was medically discharged in 2015. "complete ACL rupture, reconstruction"
Symptoms
At onset the veteran had a sudden pop and severe pain in the right knee, swelling within two hours, inability to fully straighten the knee and a feeling that the knee was unstable, together with pain and tenderness in the back of the right thigh. After onset he had intermittent swelling after long patrols, difficulty running downhill and reduced confidence in pivoting, which settled with rehabilitation by 2007.
Since the worsening in July 2012 he has had recurrent swelling, giving way on uneven ground, pain kneeling and squatting, and stiffness after sitting, persisting after reconstruction. He cannot run, jump or carry loads over uneven ground and has difficulty with stairs and ladders.
Imaging
- 22 Sep 2006 — Radiographs right knee, field hospital: "Moderate joint effusion. No fracture or avulsion."
- 20 Dec 2006 — MRI right knee: "High-grade partial tear of the anterior cruciate ligament with some intact fibres. Grade 1 sprain of the medial collateral ligament. Healing grade 2 strain of the semimembranosus at the musculotendinous junction."
- 30 Jul 2012 — MRI right knee: "Complete rupture of the anterior cruciate ligament. Bone bruising of the lateral femoral condyle and posterolateral tibial plateau. Grade 2 re-tear of the semimembranosus musculotendinous junction. Menisci intact."
Onset Date
The most likely date of onset of this condition is 21 Sep 2006.
At that date the veteran was on non-warlike service in East Timor as an airfield defence guard, deployed to a response force during civil unrest. During a night tasking he jumped about 1.2 m from the tailgate of a truck carrying about 30 kg, landed on a kerb and twisted his right knee, with immediate pain, a pop and swelling within two hours.
This date is appropriate because his pre-deployment medical of 14 March 2006 recorded normal knees with a negative Lachman test, and he presented to the field clinic the same night, 21 September 2006, with an effusion and a positive Lachman test. The onset of pain and tenderness within 24 hours of the injury meets the definition of sprain. It falls within his non-warlike service and within uninterrupted full-time service.
The sprain and strain factors require the force or forceful stretching to occur at the time of the clinical onset, not over a period before it. The landing from the truck under a 30 kg load on 21 Sep 2006 applied a significant force through the right knee and forcefully stretched the medial hamstring on that date, and pain and tenderness were recorded at both sites within hours.
For the worsening factors, the documented worsening was on 08 Jul 2012, on warlike service in Afghanistan, when the knee pivoted in an irrigation ditch under a 40 kg load. The previously partial tear, stable with a firm endpoint on 16 Nov 2011, progressed to a complete rupture with a grade 3 Lachman test, confirmed on MRI on 30 Jul 2012, and the semimembranosus strain recurred at the same moment. This was a new significant force and not recurrent sprain due to joint instability.
1. What is the formal diagnosis of the condition claimed above?
The formal diagnosis is Right Knee - Anterior Cruciate Ligament Sprain (ICD-10-AM S83.53), a high-grade partial tear of the right anterior cruciate ligament progressing to complete rupture, under the Statements of Principles concerning sprain and strain, Balance of Probabilities No. 28 of 2020 and Reasonable Hypothesis No. 27 of 2020.
A sprain is an injury involving the tearing or stretching of one or more joint ligaments, with pain and tenderness at the site within 24 hours, and includes complete tear or rupture. The anterior cruciate ligament prevents forward translation and rotation of the tibia on the femur. It is typically injured by a non-contact pivoting or landing mechanism with the knee near extension, in valgus and internal rotation, often with an audible pop and rapid haemarthrosis. A partial tear may stabilise with rehabilitation, but a further pivoting force can complete the rupture, producing instability, recurrent effusion and a high risk of meniscal damage and later osteoarthritis.
The condition began on non-warlike service in East Timor on 21 September 2006, was confirmed on MRI on 20 December 2006 and worsened to a complete rupture on warlike service in Afghanistan on 08 July 2012.
2. For each diagnosis identified, please also provide the following dates:
When did the veteran first experience symptoms attributable to this condition?
21 September 2006.
When did the veteran first present to a health / medical provider for this condition?
21 September 2006.
When was the condition confirmed / formally diagnosed?
20 December 2006.
When did the veteran first present to you (or your practice) for this condition?
14 October 2025.
3. How was this diagnosis confirmed? i.e. what were the key symptoms and signs, investigation results, specialist opinions?
The diagnosis was made clinically on 21 September 2006 and confirmed by MRI on 20 December 2006. The veteran had a typical pivoting landing mechanism, a pop, a haemarthrosis within two hours and a positive Lachman test with a soft endpoint, with no fracture on radiographs. MRI showed a high-grade partial tear of the anterior cruciate ligament. The onset of pain and tenderness within 24 hours of a tearing injury to a joint ligament meets the Statement of Principles definition of sprain.
The worsening was confirmed clinically on 08 July 2012, with a grade 3 Lachman test and positive pivot shift, and on MRI on 30 July 2012, which showed complete rupture with the characteristic bone bruise pattern. The sprain was not a recurrent sprain due to instability: the knee had been stable and asymptomatic, with a firm endpoint, on 16 November 2011. An orthopaedic surgeon confirmed the diagnosis and reconstructed the ligament on 18 October 2012.
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 21 September 2006, after 1 July 2004, during non-warlike service in East Timor. 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 operational service: his non-warlike service in East Timor in 2006, where the sprain began, and his warlike service in Afghanistan in 2012, where it worsened. The Balance of Probabilities instrument applies to his peacetime service, including his rehabilitation, training and return to full duties in Australia between 2007 and 2012.
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 Sprain and Strain, No. 28 of 2020
Causative factors
Factor 9(1): experiencing a significant physical force applied to or through the affected joint, at the time of the clinical onset of a sprain to that joint ligament; — MET
- On 21 September 2006 the veteran jumped about 1.2 m from the tailgate of a truck while carrying about 30 kg of equipment and landed with his right foot on the edge of a kerb, so that his body weight and load were driven through the right knee in valgus and internal rotation. This is a significant physical force applied through the knee at the moment of injury. He felt a pop, the knee swelled within two hours and a positive Lachman test was recorded that night. Dismounting from vehicles under load was an ordered duty.
Factor 9(2): forceful stretching or high intensity use of a muscle or tendon at the time of the clinical onset of a strain to that muscle or tendon; — MET
- As his knee gave way on landing on 21 September 2006, the veteran forcefully contracted his medial hamstring while it was being stretched in an attempt to stop himself falling, and felt a sharp pain in the back of the right thigh. The medical officer recorded tenderness over the medial hamstring that night, and MRI on 20 December 2006 showed a healing grade 2 strain of the semimembranosus at the musculotendinous junction. The strain of this muscle, which acts with the anterior cruciate ligament to restrain the tibia, was sustained in the same service incident.
Worsening factors
Factor 9(3): experiencing a significant physical force applied to or through the affected joint, at the time of the clinical worsening of a sprain to that joint ligament; — MET
- On 08 July 2012, carrying about 40 kg on a security patrol, the veteran slipped down the bank of an irrigation ditch and his right knee pivoted with the foot fixed in mud, driving his body weight and load through the knee in rotation. The partial tear, stable with a firm endpoint on 16 November 2011, progressed to a complete rupture with a grade 3 Lachman test, confirmed on MRI on 30 July 2012. The patrol was an ordered duty.
Factor 9(4): forceful stretching or high intensity use of a muscle or tendon at the time of the clinical worsening of a strain to that muscle or tendon; — MET
- In scrambling up the ditch bank under load on 08 July 2012 the veteran forcefully contracted his right hamstring while it was stretched and had sudden pain in the back of the thigh, with bruising over the medial hamstring recorded at the role 2 facility. MRI on 30 July 2012 showed a grade 2 re-tear of the semimembranosus musculotendinous junction, a measurable worsening of the 2006 strain.
Factor 9(5): inability to obtain appropriate clinical management for sprain or strain. — MET
- After the injury on 21 September 2006 no MRI, physiotherapy or orthopaedic review was available, and the veteran was returned to loaded patrol duties in a brace after one week. The high-grade partial tear was not imaged or rehabilitated for three months, until after his return to Australia, and did not regain a normal endpoint, leaving it vulnerable to the complete rupture of 08 July 2012. Under Brew v Repatriation Commission (1999) this is an inability to obtain appropriate clinical management.
Reasonable Hypothesis — Statement of Principles concerning Sprain and Strain, No. 27 of 2020
Causative factors
Factor 9(1): experiencing a significant physical force applied to or through the affected joint, at the time of the clinical onset of a sprain to that joint ligament; — MET
- The landing from a 1.2 m truck tailgate under a 30 kg load onto a kerb, which drove the right knee into valgus and internal rotation, occurred during a night response to civil unrest on non-warlike service in East Timor on 21 September 2006, at the moment the sprain began.
Factor 9(2): forceful stretching or high intensity use of a muscle or tendon at the time of the clinical onset of a strain to that muscle or tendon; — MET
- The forceful eccentric contraction of the right medial hamstring as the knee gave way on landing occurred on non-warlike service in East Timor on 21 September 2006, and produced the grade 2 semimembranosus strain recorded that night and confirmed on MRI on 20 December 2006.
Worsening factors
Factor 9(3): experiencing a significant physical force applied to or through the affected joint, at the time of the clinical worsening of a sprain to that joint ligament; — MET
- The pivoting fall into an irrigation ditch under a 40 kg load occurred on a night security patrol on warlike service in Afghanistan on 08 July 2012, and converted the partial tear into a complete rupture of the anterior cruciate ligament, confirmed on MRI on 30 July 2012.
Factor 9(4): forceful stretching or high intensity use of a muscle or tendon at the time of the clinical worsening of a strain to that muscle or tendon; — MET
- The forceful hamstring contraction while climbing out of the ditch under load on warlike service in Afghanistan on 08 July 2012 re-tore the semimembranosus musculotendinous junction, shown on MRI on 30 July 2012.
Factor 9(5): inability to obtain appropriate clinical management for sprain or strain. — MET
- On non-warlike service in East Timor in 2006 no MRI, physiotherapy or orthopaedic care was available and the veteran was returned to loaded patrols after one week, and on warlike service in Afghanistan in 2012 he waited 18 days for aeromedical return before MRI. The untreated partial tear healed with laxity and progressed to complete rupture.
The % contribution of the causes is 100% and significant.
Sequelae
The right anterior cruciate ligament sprain has led to post-traumatic instability, recurrent effusions and reconstruction, and places the veteran at high risk of right knee osteoarthritis and meniscal tears. The semimembranosus strain sustained in the same incidents is a related injury. Altered gait since 2012 has contributed to left knee and lower back pain. The loss of his trade-specific fitness, and the medical discharge in March 2015 that followed, are consequences of the worsened sprain.
The bone bruising of the lateral femoral condyle and posterolateral tibial plateau shown on MRI on 30 July 2012 indicates a significant chondral impact at the time of the worsening, which is recognised to accelerate post-traumatic osteoarthritis of the knee. Ongoing review of the right knee, including weight-bearing radiographs, is warranted.
Unintended Consequence
Met. Harvest of the patellar tendon graft for the Defence-funded reconstruction of 18 October 2012 caused anterior knee pain and pain on kneeling, which are unintended consequences of that treatment (section 6A of the DRCA and the equivalent provisions of the MRCA). The return to loaded patrol duties one week after the 2006 injury, on medical clearance in theatre, also contributed to the persisting laxity.
Inability to Attain Appropriate Medical Management
MET. After the injury on non-warlike service in East Timor on 21 September 2006 there was no MRI, physiotherapy or orthopaedic review in theatre, and the veteran was returned to loaded patrol duties in a brace after one week. The high-grade partial tear went three months without imaging or structured rehabilitation and healed with residual laxity, and in July 2012 a further 18-day delay in Afghanistan preceded MRI of the complete rupture. Applying the objective and subjective tests in Brew v Repatriation Commission (Full Federal Court, 10 September 1999, Merkel J), operational constraints that prevent recognised assessment and rehabilitation of a ligament injury amount to an inability to obtain appropriate clinical management.
5. Please provide a Health Summary and a medication / prescribing history.
See attached report.
References
- 14 Mar 2006, Pre-deployment medical, Medical Officer
- 21 Sep 2006, Field clinic record, Medical Officer, East Timor
- 22 Sep 2006, Radiographs right knee, field hospital, East Timor
- 20 Dec 2006, MRI right knee, Radiologist
- 20 Dec 2006, Orthopaedic consultation, Orthopaedic surgeon
- 16 Nov 2011, Physiotherapy assessment, Physiotherapist
- 08 Jul 2012, Role 2 medical record, Medical Officer, Afghanistan
- 30 Jul 2012, MRI right knee, Radiologist
- 18 Oct 2012, Operation report, anterior cruciate ligament reconstruction, Orthopaedic surgeon
- Statement of Principles concerning Sprain and Strain (Balance of Probabilities) No. 28 of 2020, Repatriation Medical Authority
- Statement of Principles concerning Sprain and Strain (Reasonable Hypothesis) No. 27 of 2020, Repatriation Medical Authority
