Hi there.
Permit me to address your two issues separately.
The pimples on the arm may arise due to an actual acne problem or be hereditary in nature accompanying a dry skin issue.
Ideally one has to be assessed by a dermatologist on the ground for best results.
However, you may try to use a mild peeling agent containing glycolic acid or AHA (alfa hydoxy acid) & some lotions such as Exfoliac (Merck) are ideally suited for this condition & may be applied atop wet skin after bathing for a month or so.
As for the pain in the right leg, am afraid an orthopaedic would be best suited to answer but might i suggest a positional change & use of a cushion that is geared for car seats.
Do hope both your issues sort out soon enough. Cheers & Good Luck!
Dr Praveen Rodrigues MD

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