Shaw will undergo surgery on Saturday to remove two metal bolts that were put in his leg after it snapped in two places in 2015.
The left-back came alarmingly close to having his leg amputated following the injury he suffered against PSV Eindhoven in a Champions League game seven years ago.
The double leg fracture kept him sidelined for almost seven months and a long slog back into first-team favour followed.
United interim boss Ralf Rangnick hinted the 26-year-old was still suffering the effects of the horror injury seven years on.
The German revealed the England international's substitution during the 1-1 draw against Leicester last weekend was a precautionary measure, and that he will now miss the next few weeks.
"Luke is still injured. We had to take him off at half-time and he's having problems with his leg where he had his operation back in 2015," Rangnick said.
"The doctor told me they decided to remove the metal things in his leg, there are two bolts that need to be removed and that will happen tomorrow.
"He will be out for the next two or three weeks."
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