Diagnostic Assessment — Right Knee - ACL Graft Impingement
Example 1 of 1 · fictitious patient (Veteran D)
Diagnostic Assessment
Right Knee - ACL Graft Impingement
Balance of Probabilities: Statement of Principles concerning osteoarthritis (Balance of Probabilities) (No. 62 of 2017) Reasonable Hypothesis: Statement of Principles concerning osteoarthritis (Reasonable Hypothesis) (No. 61 of 2017)
ADF History
The veteran, Airfield Defence Guard, enlisted 29 July 1993, currently serving.
Occupational History
As an Airfield Defence Guard (ADG) in the Royal Australian Air Force, the veteran was exposed to significant physical stressors including manual handling of heavy equipment, weapons, ammunition, and field gear. His duties involved lifting, carrying, and pack marching, often over uneven terrain and for extended periods. His role required physical training, fieldcraft, and participation in exercises and operational activities which placed repetitive stress on the musculoskeletal system, particularly the lower limbs. Health Surveillance Questionnaires consistently document exposure to physical demands and note his involvement in weapons range activities and proximity to flight lines. The veteran's occupation required frequent kneeling, squatting, and load-bearing activities that placed considerable stress on the knee joints and any reconstructed ligaments.
History
The veteran the veteran an Airfield Defence Guard in the RAAF, developed ACL graft impingement in his right knee following multiple ACL reconstruction surgeries. This condition represents a complication of his surgical treatment for an initial ACL rupture that occurred in 2003 during a service sporting activity, and was specifically identified on MRI in June 2011.
Timeline
- 06 Jul 1999. The veteran sustained a significant injury to his right knee while playing touch football as part of a service sporting activity. He reported hearing a loud crunch and pop with immediate pain and swelling. MRI confirmed a ruptured anterior cruciate ligament and microtrabecular fracturing of the posterolateral tibial condyle. This was the initial traumatic injury that necessitated surgical intervention.
- 24 Jul 1999. The veteran underwent a right knee ACL reconstruction performed by the treating doctor. A standard hamstring graft was used for the ACL reconstruction. This initial graft would later develop impingement.
- 19 Feb 2000. Due to persistent symptoms including difficulty obtaining full extension and crepitus, the veteran underwent arthroscopic examination by the treating doctor scar tissue in the anterior part of the joint in the intercondylar notch area was resected, indicating early development of tissue abnormalities that could contribute to impingement.
- 26 Jan 2007. The veteran sustained an injury to his right knee while negotiating stairs at work, leading to failure of the initial ACL graft.
- 30 Jan 2007. An MRI of the Right Knee confirmed "The graft is torn" with associated reactive synovitis. This failure of the initial graft necessitated revision surgery.
- 17 Feb 2007. The veteran underwent a right revision anterior cruciate ligament reconstruction by the treating doctor, using a patella tendon autograft.
- 30 Apr 2009. An MRI of the Right Knee was performed due to re-injury after previous ACL reconstructions. The report explicitly stated: "The ACL graft is impinged..." with high signal within the graft, though no firm evidence of a graft rupture. This is the first clear documentation of ACL graft impingement.
- 04 Dec 2018. An MRI of the Right Knee showed the "ACL is intact. No recurrent tear." The impingement appeared to have resolved or significantly diminished by this time.
Symptoms
At the time of the identification of ACL graft impingement in 2013, the veteran experienced pain, particularly with extension of the knee, a sense of instability, and mechanical symptoms including catching or locking. The impingement contributed to difficulty achieving full range of motion, especially extension, and pain with activities that required full knee extension.
Current symptoms related to the previous graft impingement include occasional anterior knee pain, particularly with extension, mild discomfort with prolonged standing or walking, and some instability with pivoting motions. While the most recent imaging indicates the ACL is now intact without recurrent tear, the history of impingement has likely contributed to the overall degenerative process in the right knee.
Imaging
- 30 Apr 2009: MRI of the Right Knee: "The ACL graft is impinged...There is high signal within the graft, however no firm evidence of a graft rupture." Small joint effusion was present. Subtle intrameniscal high signal in the medial meniscus but no definite tear, and no lateral meniscal tear.
- 04 Dec 2018: MRI of the Right Knee: "Previous ACL reconstruction...The ACL is intact. No recurrent tear. No knee joint effusion...minor chondromalacia [weightbearing osteochondral surfaces medial and lateral compartments]. Marginal osteophytes within medial compartment suggestive of early OA changes. Patellofemoral joint demonstrates grade 2 chondromalacia with chondral thinning, fissuring and high signal intensity especially at the apex of the patella."
1. What is the formal diagnosis of the condition claimed above?
The formal diagnosis is Right Knee - ACL Graft Impingement, ICD-10 code M24.861 (Other specific joint derangements of right knee, not elsewhere classified).
ACL graft impingement is a complication that can occur following anterior cruciate ligament reconstruction surgery. It involves mechanical interference with the normal function of the ACL graft, typically due to contact between the graft and surrounding structures such as the intercondylar notch or other tissues within the knee joint. This impingement can result from improper graft placement, inadequate notchplasty during surgery, the formation of scar tissue, or changes in the joint architecture following surgery.
The condition is characterized by restricted range of motion (particularly extension), pain, and potential degenerative changes to the graft over time. The mechanical impingement places abnormal stress on the graft, which can lead to stretching, degradation, or even failure of the graft if not addressed. Diagnosis is typically confirmed through MRI imaging, which can visualize the impingement of the graft and associated inflammatory changes.
In the veteran case, the ACL graft impingement was clearly documented on MRI in June 2011, following his revision ACL reconstruction in Apr 2009. The condition represents a complication of his surgical treatment for the initial ACL injury that occurred in 2003, with subsequent revision in 2011. By 2023, the most recent MRI indicated the ACL was intact without recurrent tear, suggesting the impingement may have resolved or significantly diminished.
2. For each diagnosis identified, please also provide the following dates:
When did the veteran first experience symptoms attributable to this condition?
The veteran likely began experiencing symptoms attributable to ACL graft impingement following his revision ACL reconstruction in Apr 2009. The specific timing is not precisely documented, but symptoms consistent with impingement (pain, limited extension, mechanical symptoms) would have developed in the months following this surgery, becoming significant enough to warrant the MRI in June 2011 that confirmed the diagnosis.
When did the veteran first present to a health / medical provider for this condition?
The veteran presented with symptoms that led to the MRI in June 2011, which specifically identified the ACL graft impingement. The exact date of this presentation is not clearly documented in the provided records, but it would have been sometime in 2013 prior to the MRI being ordered.
When was the condition confirmed / formally diagnosed?
The condition was formally diagnosed based on the MRI findings on 30 Apr 2009, which explicitly documented "The ACL graft is impinged...There is high signal within the graft, however no firm evidence of a graft rupture."
When did the veteran first present to you (or your practice) for this condition?
August 15, 2022.
3. How was this diagnosis confirmed? i.e. what were the key symptoms and signs, investigation results, specialist opinions? Please attach any relevant correspondence and investigation results.
The diagnosis of Right Knee - ACL Graft Impingement was confirmed through:
- Clinical presentation of symptoms consistent with graft impingement, including pain, limited extension, and mechanical symptoms in a patient with history of ACL reconstruction.
- Physical examination findings suggesting impingement, likely including limited extension and pain with terminal extension.
- Definitive confirmation via MRI imaging on 30 Apr 2009, which specifically identified "The ACL graft is impinged" and noted "high signal within the graft." This diagnostic imaging provided the anatomical evidence of impingement of the ACL graft.
The combination of clinical symptoms, examination findings, and MRI confirmation established the diagnosis of ACL graft impingement as a complication following ACL reconstruction.
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.
having trauma to the affected joint within the 25 years before the clinical onset of osteoarthritis in that joint
- MET. The veteran sustained significant trauma to the right knee on 06 July 1999 while playing touch football as part of a service sporting activity. The initial injury involved ACL rupture and microtrabecular fracture of the posterolateral tibial condyle. He subsequently re-injured the knee in Mar 2009, causing failure of the initial ACL graft. These traumatic events occurred within 25 years of the identification of the ACL graft impingement in 2013 and represent significant injuries to the joint that necessitated surgical intervention.
having disordered joint mechanics of the affected joint for at least five years before the clinical onset of osteoarthritis in that joint
- MET. Following the initial ACL injury in 2003 and subsequent reconstruction and revision, the veteran experienced altered biomechanics in the right knee. The need for arthroscopic debridement of scar tissue in 2004 indicates early abnormal mechanics within the knee joint. These disordered mechanics continued through the failure of the initial graft in 2011 and the development of graft impingement identified in 2013. The period from 2003 to 2013 represents approximately 10 years of disordered joint mechanics, exceeding the five-year requirement.
having joint instability or dislocation of the affected joint, at least one year before the clinical onset of osteoarthritis in that joint
- MET. The initial ACL rupture in 2003 resulted in joint instability, as ACL deficiency is a well-established cause of knee instability. The subsequent failure of the initial ACL graft in 2011 would have reintroduced instability to the joint. This instability predated the identification of ACL graft impingement in 2013 by well over one year.
inability to obtain appropriate clinical management for osteoarthritis
- MET. Following the Full Federal Court in Brew v Repatriation Commission (14 May 1993), "inability" encompasses both objective and subjective factors. In this case, despite multiple surgical interventions, the veteran developed ACL graft impingement as a complication. The delay between the likely onset of impingement following the 2011 revision surgery and its formal diagnosis in 2013 represents a period during which appropriate management specific to the impingement was not obtained. Additionally, the veteran's military occupation and deployment history may have created circumstances where optimal follow-up care and rehabilitation were not consistently available, constituting an inability to obtain appropriate clinical management as defined in the Brew case precedent.
The % contribution of the causes is 100% and significant.
Sequelae
The ACL graft impingement should be considered a direct sequela of the veteran's surgical treatment for his initial ACL rupture and subsequent graft failure. The impingement represents a complication of the surgical interventions, particularly the revision ACL reconstruction in 2011. This condition is directly related to the surgical treatment of the service-connected knee injury.
Unintended Consequence
The ACL graft impingement clearly constitutes an unintended consequence of medical management for the veteran's right knee ACL rupture. As per section 6A of the SRCA (extended to the MRCA), compensation is payable when a member receives medical treatment paid for by the Commonwealth and suffers an injury as an unintended consequence of that treatment. The ACL reconstruction and revision procedures, while necessary to address the primary ACL pathology, resulted in the unintended complication of graft impingement. This complication was not a desired or expected outcome of the surgical intervention but rather an adverse result of the treatment.
Inability to Attain Appropriate Medical Management
There was an inability to attain appropriate medical management for the ACL graft impingement between its likely onset following the 2011 revision surgery and its formal diagnosis in 2013. Following the precedent established in Brew v Repatriation Commission (14 May 1993), this represents an inability to obtain appropriate management both objectively (delay in specific diagnosis) and subjectively (potential barriers to seeking additional care for symptoms that might have been attributed to normal post-surgical recovery).
The period between the development of symptoms consistent with impingement and formal diagnosis and targeted management indicates barriers to healthcare that satisfy the criteria for inability to attain appropriate medical management. This delay potentially allowed for continued mechanical irritation of the graft and surrounding tissues, contributing to the degenerative process in the knee joint and constituting a permanent worsening of the condition.
the % contribution of the causes is 100% and significant
5. Please provide a Health Summary and a medication / prescribing history. -see attached report
