The First Few Days: Hospital and Going Home

You will spend one to three days in the hospital after knee replacement surgery. During this time, a physical therapist will visit your room to help you stand and walk short distances, usually within hours of surgery. Your leg will be elevated, iced, and wrapped in compression bandages to reduce swelling. You will receive pain medication on a schedule, not just when you ask for it — this keeps pain manageable and lets you move more easily during therapy.

Before you leave the hospital, the staff will teach you how to use crutches or a walker, how to climb stairs safely, and what movements to avoid. You will also receive written instructions about wound care, when to take your medications, and which activities are off-limits. Take these home and follow them exactly — they are specific to your surgery and your surgeon's approach.

Most people go home with a prescription for pain medication, antibiotics to prevent infection, and sometimes a blood thinner to prevent clots. You will also have a follow-up appointment scheduled, usually two to three weeks after surgery. Do not skip this visit — your surgeon needs to check the incision and assess how well you are moving.

Key Takeaways

  • Physical therapy begins in the hospital and continues at home or an outpatient clinic for several weeks; skipping sessions slows your recovery and increases stiffness.
  • Swelling and bruising peak around day three to five, then gradually improve over weeks; ice, elevation, and compression bandages are your main tools to manage it.
  • Pain typically decreases noticeably by week two to three, but you may need medication for four to six weeks; taking it on schedule rather than waiting for pain to return works better.
  • Most people can put weight on the leg within days and walk with information within a week, but returning to normal activities takes three to six months depending on your starting fitness and the type of replacement.
  • Infection, blood clots, and stiffness are the main complications to watch for; call your surgeon when ready if you see signs like fever, calf swelling, or inability to bend the knee past a certain point.

Swelling and Bruising in the First Two Weeks

Swelling is normal and expected. Your knee will look puffy and feel tight, especially in the first few days. The swelling usually peaks around day three to five, then slowly improves over the next two to three weeks. Bruising often appears on the shin, calf, or inner thigh a few days after surgery and can look dramatic — this is normal and will fade.

To manage swelling, follow the RICE protocol: rest, ice, compression, and elevation. Ice your knee for 15 to 20 minutes at a time, several times a day, for the first two weeks. Use a compression bandage or sleeve to keep pressure on the knee. When sitting or lying down, prop your leg up on pillows so your knee is higher than your hip. At night, sleep with a pillow under your calf so your heel is elevated but your knee is not hyperextended.

Swelling that gets worse instead of better, or swelling that appears suddenly after improving, can signal a problem like infection or blood clot. Call your surgeon if this happens. Also call if you develop calf pain, warmth, or redness, or if you cannot straighten your leg due to swelling.

Pain Management and Medication

Pain after knee replacement is significant but manageable. Most people describe it as a deep, achy pain rather than sharp pain. The intensity usually drops noticeably by the end of week two. You will likely take prescription pain medication for four to six weeks, though some people need it longer.

Take pain medication on a schedule, not just when pain breaks through. This keeps your pain level lower and makes it easier to participate in physical therapy. As pain improves, your surgeon may recommend switching to over-the-counter acetaminophen or ibuprofen. Do not stop medication abruptly — taper it gradually as directed by your surgeon.

Some swelling and mild discomfort can persist for months, especially after activity. This is normal. If pain suddenly worsens, or if you develop sharp pain in the calf or behind the knee, contact your surgeon — these can be signs of complications.

Physical Therapy: What Happens and Why It Matters

Physical therapy is not optional — it is the main tool that determines how well your knee works after surgery. You will start in the hospital and continue either at an outpatient clinic or at home, depending on your surgeon's recommendation and your insurance. Most people attend therapy two to three times per week for six to twelve weeks.

Early therapy focuses on reducing swelling, restoring the ability to straighten your leg fully, and building enough strength to walk without information. Your therapist will teach you exercises to do at home — typically 20 to 30 minutes, once or twice daily. These exercises are not optional; they are as important as the surgery itself. People who skip home exercises or miss appointments often develop stiffness and weakness that takes months longer to overcome.

As weeks pass, therapy progresses to walking longer distances, climbing stairs, and eventually light strengthening work. By three months, most people can walk a mile and climb stairs normally. By six months, many return to activities like golf, swimming, or light hiking. Full recovery — including return to high-impact activities like running — typically takes nine to twelve months.

Walking, Stairs, and Daily Activities

You will use crutches or a walker for the first week or two. Most people can put weight on the leg when ready after surgery, but you will not feel confident doing so at first. By the end of week one, many people walk short distances with a walker or one crutch. By week three to four, most people walk without information, though they may still move slowly or favor the leg.

Stairs are harder than walking on flat ground. You will learn the technique in the hospital: step up with your good leg first, then bring the surgical leg up to meet it. Coming down, lead with the surgical leg. Use a handrail and take your time. Most people can manage stairs by week two to three, but some take longer. Do not rush this — a fall can set back your recovery significantly.

Avoid high-impact activities like running, jumping, or contact sports for at least three to six months. Swimming and stationary cycling are usually safe by week six to eight, once the incision is fully healed. Driving is typically safe once you stop taking prescription pain medication and feel confident controlling the leg — usually two to four weeks after surgery, but check with your surgeon first.

Wound Care and Signs of Infection

Your incision will be closed with stitches or staples, which are usually removed around two weeks after surgery. Until then, keep the area clean and dry. You can shower once the surgeon says the incision is sealed — usually a few days after surgery — but do not soak the knee in a bath or pool. Pat the incision dry gently after showering.

Some oozing, redness, and warmth around the incision are normal for the first week or two. However, call your surgeon when ready if you see pus, if the redness spreads, if the incision opens, or if you develop fever. These are signs of infection, which requires prompt treatment. Also call if you notice increasing warmth, swelling, or redness in the calf — this can signal a blood clot.

Once the incision is fully healed and stitches are removed, you can resume normal bathing and swimming. Scar tissue will continue to soften and fade over several months to a year.

Sleep, Positioning, and Comfort

Sleep is difficult in the first few weeks because of pain and the need to keep your leg elevated and protected. Sleep on your back with a pillow under your calf, or on your non-surgical side with a pillow between your knees. Do not sleep on your surgical side for at least the first few weeks — this puts pressure on the incision and can increase swelling.

Many people find that pain medication taken 30 minutes before bed helps them sleep. Some also use ice before bed to reduce swelling and discomfort. A bed rail or trapeze bar can help you move in and out of bed without putting stress on your knee. By week three to four, most people sleep more normally, though some continue to prefer sleeping on their back.

During the day, change positions frequently. Sitting in the same position for hours can increase stiffness. Get up and walk short distances every hour or two, even if it is just to the kitchen and back.

When to Call Your Surgeon

Contact your surgeon when ready if you experience fever above 101°F, increasing redness or warmth around the incision, pus or drainage from the incision, sudden increase in swelling or pain, calf pain or swelling, inability to straighten your leg, or chest pain or shortness of breath. These can signal infection, blood clots, or other serious complications.

Also call if you have questions about your medications, if pain is not controlled by your current medication, or if you are unsure whether an activity is safe. Your surgeon's office expects these calls and would rather hear from you than have you guess and cause a setback.

Frequently Asked Questions

How long before I can drive?

Most surgeons clear you to drive once you stop taking prescription pain medication and feel confident controlling the leg — usually two to four weeks after surgery. However, check with your surgeon first, as the timeline depends on which leg was operated on and how quickly you are recovering. If your right knee was replaced, you may need to wait longer.

Can I go back to work?

This depends on your job. If you have a desk job, you may return within two to four weeks. If your job requires standing, walking, or physical labor, you will likely need four to twelve weeks off. Talk to your surgeon about your specific job duties — they can give you a realistic timeline and may provide a note for your employer.

Is it normal to feel like the knee is not stable?

Yes, especially in the first few weeks. This feeling usually improves as swelling decreases and strength returns. By six to eight weeks, most people feel much more confident. If the feeling of instability persists beyond three months, mention it to your physical therapist or surgeon — they may adjust your therapy.

What if I am not making progress in physical therapy?

Progress is not always steady. Some weeks you will feel stronger, other weeks you may feel stuck. If you have not seen improvement over several weeks, or if pain is worsening, tell your surgeon or therapist. They may adjust your therapy plan, check for complications, or recommend a different approach.

When can I return to sports or exercise?

Low-impact activities like swimming and stationary cycling are usually safe by six to eight weeks. Walking and golf typically resume by three to four months. High-impact activities like running or tennis usually require six to twelve months of recovery. Your physical therapist can guide you on when each activity is safe based on your strength and range of motion.