Can Aviation Ordnance Personnel Duties Cause Knee Strain and Arthritis?
Yes, the military occupational specialty duties of aviation ordnance personnel can directly cause knee strain and lead to osteoarthritis of the knee, as these roles involve the exact high-risk physical activities—heavy lifting, frequent kneeling, squatting, and repetitive joint use—that are strongly associated with knee OA development according to VA/DoD guidelines. 1
Evidence Linking Military Occupational Activities to Knee OA
The 2020 VA/DoD Clinical Practice Guideline explicitly identifies that "heavy work activities (e.g., farming and construction work) or work that requires frequent kneeling, heavy lifting, or repetitive use of joints are associated with the development of OA" and specifically notes that "the activities that place patients at higher risk for OA are an integral part of the daily duties of many who serve or have served in the US military." 1
Specific High-Risk Work Activities
Aviation ordnance personnel routinely perform activities with strong evidence for increased knee OA risk 2:
- Kneeling, squatting, and bending: Strong evidence in both men and women for knee OA development
- Heavy lifting: Strong evidence for increased hip OA risk, with moderate to limited evidence for knee involvement
- Heavy physical demands: Strong evidence for knee OA in men
The systematic review evidence demonstrates that when kneeling, squatting, and bending activities are combined (as they typically are in real-world military work), there is strong to moderate evidence for knee OA across both sexes, even though individual activities examined in isolation may show weaker associations 2. This is particularly relevant for aviation ordnance work, which involves loading/unloading munitions while kneeling or squatting in confined aircraft spaces.
Military-Specific OA Burden
Military service members face disproportionate knee OA rates. During 2016-2020, 38.8% of all incident OA diagnoses in active component service members involved the knee, making it the single most affected joint 3. The crude overall rate of incident OA was 630.9 per 100,000 person-years, with rates highest among:
- Male service members
- Those aged 35 or older
- Army members
- Those in physically demanding occupations
The daily demands of military service place service members at baseline increased risk of developing primary OA as well as increased risk of acute knee injuries that further predispose to developing posttraumatic OA 4.
Mechanism and Pathophysiology
Aviation ordnance duties create knee strain through:
- Repetitive mechanical loading: Constant kneeling/squatting while handling heavy ordnance damages articular cartilage
- Acute injury risk: Heavy lifting and awkward positioning increase meniscal tear risk, which strongly predisposes to posttraumatic OA
- Cumulative joint stress: The combination of weight-bearing in flexed positions plus load-carrying accelerates cartilage degeneration
Clinical Implications for Documentation
When evaluating aviation ordnance personnel for service-connected knee conditions, document:
- Specific duty requirements: Frequency and duration of kneeling, squatting, lifting (weight and repetitions)
- Confined space work: Aircraft munitions bays requiring prolonged awkward positioning
- Load characteristics: Typical ordnance weights handled (often 50-500+ lbs with assistance)
- Career duration: Cumulative exposure years in the MOS
- Acute injury history: Any documented meniscal tears, ligament injuries, or patellofemoral pain during service
The evidence is particularly strong when multiple risk factors coexist—for example, an overweight aviation ordnance technician with 10+ years of service performing daily heavy lifting and kneeling has compounding risk factors that substantially elevate OA probability 1, 2.
Important Caveats
Not all knee pain in aviation ordnance personnel is OA. The differential includes:
- Patellofemoral pain syndrome (affects 3.4% of active duty, with 4-fold increased subsequent OA risk) 5
- Meniscal tears (significantly associated with Infantry MOS but relevant across physically demanding roles) 6
- Mechanical low back pain with referred symptoms
However, the occupational exposure itself is sufficient to establish plausible causation for knee OA in aviation ordnance personnel, particularly when radiographic evidence confirms structural changes consistent with the work-related mechanism 1, 2.