Brief Answer:
Can be following a trauma

Detailed Answer:
Hello,
Thanks for posting your query,

I have gone through your query and have also viewed the attached picture.

The knee is divided into three compartments- medial, lateral and patellofemoral compartments. Osteoarthritis being a degenerative condition is age related and when it is confined to any one particular compartment, it is termed as unicompartmental osteoarthritis of knee.

This can happen due to many reasons:
- in malaligned knees- where undue stress falls on any one compartment and its attached bones and ligaments.

- in cartilage injury following an trauma

- in meniscal injury

The above factors states that, this can also result following an accidental trauma, which in long term lead to unicompartmental osteoarthritis.

Hope I have answered to your query

Please feel free to discuss further or else kindly close and give your valuable feedback.

Warm regards
Wishing a fast recovery.

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Brief Answer:
Explained below in detail

Detailed Answer:
Hi again,
Thanks for the follow up,

In knee osteoarthritis, the cartilage protecting the bones of the knee slowly wears away. This can occur throughout the knee joint or just in a single area of the knee.

By stating this, it means that it is not mandatory that a history of trauma is present.

In your cases, since the patient says there is a history of trauma, signs like mal-alignment of the knee following the trauma may result in this condition. It is also mentioned in the inpatient records stating the degree of varus and flexion. This can be the consequence of past trauma.

Other than that, it would be difficult to conclude if its trauma related or not, as osteoarthritis in general is a chronic process and the resultant changes following trauma would not be evident at this point of time.

Hope I have made it clear for you,

Thanks and regards

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