After knee replacement, sudden chest pain or trouble breathing needs emergency care; new calf pain, worsening wound changes, or a major loss of function needs prompt assessment. Bruising, stiffness, and some swelling are common, but a new symptom or a clear turn for the worse deserves a different response from yesterday’s familiar soreness.
Use the three action levels below alongside your discharge instructions. The point is to recognize a change, choose the right route, and explain it clearly—not to diagnose the cause at home. Our knee replacement recovery hub covers the wider journey.
Emergency: call 911 instead of waiting for a callback
Call 911 for sudden shortness of breath, sudden chest pain, or chest pain with coughing after knee replacement. These can signal a pulmonary embolism, a clot that has traveled to the lungs. AAOS lists these warning signs. Do not wait to see whether another icing session helps, and do not drive yourself.
You do not need to have noticed calf symptoms first. Tell the dispatcher that you recently had knee replacement, give your location, and describe when the breathing or chest symptoms began. Have a helper bring the medication list if it is readily available; finding paperwork should not delay the call.
Same day: new calf pain or a distinct swelling change
A sore knee after exercise and a newly painful calf are different problems. New or increasing calf pain, tenderness, redness, or swelling—especially when one leg changes noticeably—can indicate DVT. Dorset County Hospital’s symptom guide recommends quick assessment for these changes.
Call the surgical team’s urgent or after-hours number when the change appears. Say “new calf pain after knee replacement” early in the conversation. Ask where to be assessed today. If that service cannot arrange timely assessment, seek urgent in-person care rather than waiting for the next therapy appointment. Add chest pain or breathing difficulty, and the action changes to 911.
Do not use your ability to walk, a photograph, or a temporary improvement with rest to rule out a clot. Those observations can help describe the situation, but they cannot establish what caused it.
Same day: a wound that is getting worse
Report increasing redness, tenderness, swelling, worsening pain, or fluid leaking from the incision. Pus, a new unpleasant odor, or a dressing becoming repeatedly wet also deserves prompt contact. The NHS knee-replacement complications guide identifies worsening wound symptoms and discharge as reasons for urgent help.
Keep the dressing in place according to the instructions you received. Do not peel it back just to produce a better photograph, squeeze the incision, or put scar cream on a draining area. If a photograph is requested, use the team’s approved upload route and include the time it was taken. Our incision and scar-care guide explains the difference between protecting a healing wound and later scar care.
Do not wait for a fever before reporting these changes. AAOS explains that joint-replacement infection can have subtle symptoms, including increasing pain or stiffness in a knee that had been functioning well. Report fever or shaking chills too, using the temperature threshold in your discharge plan.
Prompt contact: pain or function changes sharply
Contact the surgical service if your pain remains poorly controlled despite taking medication as directed, or if you suddenly cannot do a task you could do earlier, such as safely standing or using your walker. A fall followed by new knee pain or loss of function needs assessment rather than a harder exercise session. MedlinePlus discharge guidance also flags persistent pain despite medication and a foot or toes becoming unusually dark or cool.
Pause the activity that triggered the problem and keep your walking aid available. Explain what changed: “I could get to the bathroom this morning; now I cannot put weight through the leg.” That is more useful than saying only “my recovery is going badly.” Do not double medication doses or try to force the knee through the new limitation.
Often expected: symptoms that follow a familiar pattern
Bruising can spread down toward the ankle. Swelling can involve the knee and lower leg and take months to settle. A small numb patch beside the incision is also common. Dorset’s recovery guide describes these patterns. The distinction is that a familiar symptom is being monitored—not automatically explaining away a new, worsening, or different one.
For example, a knee that feels stiff after sitting but loosens with the movement you were taught is different from a sudden loss of motion. An afternoon increase in familiar puffiness is different from a newly tender calf. Keep using your assigned walking routine and home cold-therapy plan for ordinary recovery symptoms; use the urgent routes above when the pattern changes.
Make the call easier before you need it
Save the daytime surgical number and the after-hours number in your phone before surgery. Put a printed copy beside the discharge papers. Confirm which number reaches a person when the office is closed; a routine portal message may not be monitored quickly enough for an urgent change.
When you call, have five details ready: surgery date and side; the new symptom; when it began; how it differs from earlier; and any associated temperature, wound, breathing, or walking change. Keep your medication list nearby, including the name and last dose of any prescribed blood thinner.
A useful opening sounds like this: “I had my right knee replaced six days ago. Since lunch my calf has become newly painful and more swollen. I have no chest pain or breathing difficulty. Where should I be assessed today?” Write down the advice, the person’s name, and the next step. If symptoms worsen while waiting, reassess the urgency.
Two common questions
Is clicking by itself an emergency?
Metal and plastic knee components can click during movement; AAOS describes this as common. New clicking with pain, instability, a fall, or loss of function is a different situation and should be reported.
Should I wait until Monday if I am unsure?
Use the after-hours service for a new concerning change over the weekend. Routine questions about a stable exercise plan can wait for the planned appointment; suspected clot symptoms, worsening wound changes, or abrupt loss of function should not be parked in a routine message queue.
Know the next step, not just the symptom
Keep emergency symptoms, same-day assessment needs, and familiar recovery patterns separate. A prepared contact list and a clear description make it easier to act promptly without turning every ordinary ache into an alarm.
