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1.The most possible cause could be
ganglion - usually exist from the
nerve, tendon and joint space.
2.They are painless, asymptomatic, does not need any acute treatment.
3.Usually seen in the sports persons involving active limb movement.
4.If you feel any growth in the lump - an
ultrasound is investigation of choice to evaluate the nature of the lesion, its source and extensions.
5.Suggest to monitor the lesion for any changes, and no active intervention is needed.
Good luck.
Hope i have answered your query,
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