Brief Answer:
Need careful review, more information would be nee

Detailed Answer:
Hi and thanks for the query,

It might be necessary to distinguish this burning sensation from pain. Considering the first scenario, where it is mainly a burning sensation, knowing the mode of onset, whether it was abrupt or gradual, mild, moderate or intense, if it is your very first time experiencing this are of utmost importance. Do you experience this sensation all the time or it is periodic, what intensifies, triggers or moderates the sensation are all important to be known.

Is the sensation like something electrical, where once you experience it at the groin you also experience the same sensation at the level of the knees? Where exactly did it start, from groins, knees or both sites at the same time. All these might be required from a proper diagnosis. Associated skin eruptions around the area would give possibility of zona. Painful sensations, in case there is a past history of rheumatological or traumatic disease, especially if the sensation radiates from groin to knee would imply a nerve root compression.

Inflammation of specific nerves, called peripheral neuropthies, as seen in diabetes and other systemic inflammatory diseases could cause burning sensations, but rare affecting exclusively the groin and knees. It is imperative to check for associated muscle loss or atrophy, the tone, muscle strength around this area. Screening for vitamin deficiencies, especially of the B group be useful for the start.

Vitamin B gradual supplementation, Amitriptiline and Gabapentin could be initial relief options as you await to see your doctor. In case of pain, pain killers and anti inflammatory drugs could be used with caution.

Thanks and kind regards

DR Bain

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