ِA scalpel مبضع is a small straight knife with a thin sharp blade used in surgery and dissection.

The fragment that you posted is hard to comprehend without context.

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Note added at 2003-05-29 09:43:34 (GMT)
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It is possible that the sentence was incorrectly written. For instance, the writer may have meant

اسـتعمل مبضعاً في جسـدي

He operated on me using a scalpel (roughly speaking).

Or the writer may have meant:

اسـتُعمِل مبضعٌ في جسـدي

I underwent a a procedure involving the use of a scalpel.

Or the writer may have meant:

عمل بضعاً في جسدي

He made an incision in my body.

Or even possibley:

عُمل بضعٌ في جسدي

I underwent an incisional procedure.

These are all guesses, because the Arabic fragment does not read like standard Arabic, technical or non-technical.