Brief Answer: Detailed below. Detailed Answer: Hello! Thank you for the query. Generally kidney bruise or hematoma does not give pain, discomfort or any other feeling. Kidney gives pain when inflammation is present. So your bruise like feeling is not caused by kidney. Most likely what you feel is a muscle. Sometimes when lifting heavy objects or bending using this part of body, the muscle in this area can become a little bit swollen and painful. If you find this might be a muscle try to see if the feeling will go away within few days. If it wont go away or you feel its something else, ultrasound of this area should be done. Hope this will help. Feel free to ask further questions. Regards.

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