Total Knee Replacement: Your Preoperative Guide

Knee replacement may be considered when usual treatment does not relieve pain and stiffness and walking, sleep, or everyday tasks are limited. The aim is less pain and better function; results and recovery speed vary. This guide explains the decision, preparation for surgery, and planning the return home and to daily life. It focuses on primary total replacement of one knee.

🦴 What is knee osteoarthritis, and when does it need surgery?

Cartilage covers the end of the thigh bone, the top of the shin bone, and the back of the kneecap. This smooth surface helps the joint move with little friction. In osteoarthritis, cartilage and other joint tissues change, and the knee may become painful, stiff, or swollen. Pain on standing and walking, difficulty with stairs, and reduced bending and straightening are common complaints.

Pain severity does not always match the X-ray appearance. Therefore, surgery is not chosen from joint-space narrowing alone; examination, limitations, and your response to treatment matter too. Leg deformity or night pain may add to the problems. Do not automatically attribute sudden pain, marked redness or fever to osteoarthritis. If knee pain suddenly becomes very severe, or fever occurs with redness or warmth around the knee, seek urgent assessment at a medical centre now.

Suitable exercise, weight management if overweight, and appropriate medicines can help control symptoms. A cane or certain injections may also help in particular circumstances. These treatments do not rebuild lost cartilage, but may allow an acceptable quality of life and delay surgery. Continuing useful treatment is reasonable; endlessly repeating ineffective treatment is unnecessary.

Replacement becomes an option when pain and limitations seriously impair quality of life and non-surgical treatment is insufficient. The surgeon weighs benefits and risks alongside other illnesses, skin and bone condition, and your goals. Surgery does not restore the natural knee of your youth; some pain or movement limitation may remain. Walking to shop or sleeping better is a more realistic goal than a promise of a completely pain-free knee.

⏳ What happens if you do not have surgery?

Knee replacement for osteoarthritis is usually elective. If non-surgical treatment keeps pain manageable and life acceptable, an X-ray alone is no reason to have surgery. Arthritis progresses at different rates; not every short delay harms the surgical result. Follow-up helps track changes in pain, movement, and daily ability.

For some patients, increasing pain leads to less activity, weaker muscles, and reduced movement. Severe deformity or stiffness may also complicate treatment and rehabilitation. These possibilities justify discussing timing, rather than fear or an immediate obligation to operate. If sleep, walking, and independence remain impaired despite appropriate treatment, do not wait for complete disability before reassessment.

Do not spend the waiting period in complete rest. Tolerable low-impact activity, maintaining strength, and correct use of a walking aid can help preserve current ability. Discuss treatments that worsen pain or no longer help. The final decision should account for your treatment needs, time to prepare, and support at home.

🏋️ Preparing for surgery

Preparation includes maintaining movement, suitable strengthening, and learning tasks you will need after surgery. Evidence supports improvements in some strength and function measures with preoperative programmes, but the size and duration of benefit vary. The aim is to start from a better position; intense exercise to compensate for arthritis is not the goal.

Reduce activity and assess the cause if exercise causes sharp pain or more swelling. Short walks on level ground and low-impact activity, when tolerable, are preferable to prolonged immobility. Strength training should match your current ability. Before surgery, learn how to rise from a chair, walk with a walker, and use stairs.

Managing blood glucose, checking anaemia, and treating active infection are part of preparation. Make a full list of medicines and supplements and obtain clear instructions about changes. Smoking affects wound healing; seek help to stop. Weight loss may help when needed, but weight or age alone does not replace an individual surgical assessment.

Prepare a firm chair with arms, a suitable walking aid, and a well-lit route to the toilet. Arrange shopping, meals, transport, and help for the first days. Stairs at home are not necessarily always forbidden; you will practise safe use before discharge. Keep frequently used items within reach to avoid unnecessary bending and trips.

🏥 The day before surgery and the day of surgery

The sequence is similar in most centres: admission and changing into theatre clothing, checking vital signs and inserting an IV line, meeting the anaesthetist and signing consent, and the surgeon marking the correct leg. Site marking is a standard safety step; remind the team if it has not happened. You then go to the operating room. Your family waits during this time, and the surgeon tells them the outcome after surgery.

• Fasting: For healthy adults having scheduled, non-emergency surgery, allow at least 2 hours between the last clear liquid, such as water, and anaesthesia, 6 hours after a light meal, and at least 8 hours after fatty food or meat. Milk is not a clear liquid. Diabetes, delayed stomach emptying, and some medicines may change the plan; your anaesthetist’s written instructions take priority.
• Medicines: Bring a complete list of the medicines, supplements, and herbal products you take. Daily medicines, particularly blood thinners and diabetes medicines, must be discussed with the surgeon and anaesthesia team beforehand; do not stop or add any medicine on your own.
• Bathing: Shower the night before or on the morning of surgery according to hospital instructions. Do not shave the surgical area at home with a razor; small cuts can provide an entry point for infection.
• Bring: Identification and insurance documents, recent X-rays and tests, a medicine list, a walker or cane, comfortable loose clothing, and shoes with a closed back, low heel, and non-slip sole.
• Remove nail polish and jewellery, and arrange a companion for the day of surgery and the first days at home.

⚕️ How is knee replacement performed?

Both spinal and general anaesthesia are possible. The anaesthetist chooses according to your illnesses, medicines, and circumstances. Spinal anaesthesia numbs the lower body, and you may also receive sedation. Postoperative pain control is explained before you enter the operating room.

The surgeon reaches the joint from the front of the knee and prepares the damaged thigh-bone and shin-bone surfaces. Metal components cover those surfaces, with a durable plastic piece between them allowing smooth movement. The knee bones are not removed in their entirety; the aim is to replace damaged joint surfaces and achieve appropriate balance.

In this clinic, resurfacing the back of the kneecap is selective. The surgeon decides whether to retain or replace its surface according to cartilage and joint condition. “Total knee replacement” does not mean every patient must have the kneecap resurfaced. Partial replacement may be an option when damage affects only a particular part of the knee; this guide concerns total replacement.

Component type and fixation match the bone condition and the design of the artificial joint, or prosthesis. Once installed, the surgeon checks leg alignment, ligament balance, and knee movement. Tissues are then closed and dressed, and you go to the recovery area for monitoring after anaesthesia. These steps help explain the operation; prosthesis brand or price alone does not determine outcome quality.

Consent discussions cover risks such as infection, clots, stiffness, persistent pain, and possible further surgery. Most patients benefit from less pain and improved daily tasks, but results are not guaranteed. Muscle ability, preoperative condition, and rehabilitation participation affect recovery. High-impact activities are usually not the main goal of knee replacement.

🗓️ Recovery at a glance

The usual stay in this clinic is 1 to 2 nights, with weight bearing as tolerated using a walker from the day of surgery. A walker is usually needed for 2–4 weeks, followed by a cane until walking without a limp. If you cannot yet lift a straight leg without the knee bending, use the prescribed splint while walking. A brace and a continuous passive motion machine are not routinely prescribed.

Rehabilitation begins with pain and swelling control, knee movement, and walking practice, then progresses with strength. Pain and swelling after activity may persist for a while; a continuous increase needs assessment. Read the guide to care and rehabilitation after knee replacement for the complete dressing, medicine, and exercise plan and for warning signs.

🎯 Returning to everyday life: answers to 20 questions

🤕 1) How much pain will I have, and how long will it last?

Pain and swelling are greatest during the first days to weeks; mild to moderate swelling may last 3–6 months. The overall trend should be improvement. Contact the clinic for assessment if pain is new, increasing, or not controlled by your prescription.

🏥 2) How many nights will I stay in hospital?

The usual stay in this clinic is 1 to 2 nights. Pain control, moving with a walker, and general health affect discharge. Arrange help at home before surgery; a short stay does not mean you will need no help.

🚶 3) When can I put weight on the operated leg?

You start weight bearing as tolerated with a walker on the day of surgery. This does not mean long walks or pushing through severe pain; start with short, safe routes. Keep the walker for balance and to reduce extra strain.

🩼 4) How long will I need a walker or cane?

A walker is usually needed for 2–4 weeks, then a cane until you walk without a limp; this stage often lasts to around 6 weeks. Do not stop too early if you still lean heavily on the aid or the knee gives way. Hold the cane in the hand opposite the operated leg.

🧵 5) When are stitches or staples removed?

Stitches or staples are usually removed around two weeks (14 days) after surgery. The dressing stays until the first visit unless it becomes wet, dirty, loose, or blood-stained earlier. The wound and need for continued covering are checked at that visit.

🧑‍⚕️ 6) When does physiotherapy start, and how long does it continue?

Simple exercises begin on day 1 and formal physiotherapy on day 2. For planning, early rehabilitation takes place in the first 6 weeks, with strengthening and gait improvement continuing during months 3–6. The number and duration of in-person sessions depend on progress; not everyone needs prolonged sessions. Report stalled movement recovery or increasing pain and swelling for assessment.

🚗 7) When can I drive?

Driving is usually considered around 6 weeks after surgery for either knee. You must perform an emergency stop without pain or delay and take no opioid painkiller or sedating medicine. Safe entry and exit and full control of the car are also needed.

💻 8) When can I return to desk or seated work?

Desk work usually resumes 4–6 weeks after surgery. Start with shorter hours and opportunities to get up and move briefly. Adjust the workload gradually if commuting, sitting, or work increases swelling.

🏭 9) What about standing or heavy work?

Heavy work is usually considered around 3 months. Standing work is usually considered 6–12 weeks after surgery, once you no longer need a cane and can walk without a limp; the duration of standing and the surface matter, and it should increase gradually. Ladders, carrying loads, and uneven surfaces require more strength and balance than office work.

🪜 10) How should I use stairs?

At first, take stairs one step at a time: lead with the unaffected leg going up, and with the walking aid followed by the operated leg going down. Hold the handrail and have someone with you until your strength and balance are adequate. Practise stairs in hospital; do not carry the walker onto a step while relying on it for support.

🛌 11) How should I sleep?

Sleep on your back or in a comfortable position that does not keep the knee bent for long periods. Do not put a pillow directly under the knee; support the calf and heel to elevate the leg. A pillow between the legs may reduce pressure when sleeping on your side.

🚿 12) When can I shower?

A short shower may be possible from 48 hours after surgery if the wound is dry and the waterproof dressing is intact and firmly attached. Do not direct a strong stream of water onto the dressing; if water gets underneath it, change it the same day. A shower chair and a helper reduce the risk of a fall during the first showers.

🕌 13) How should I pray?

Pray on a chair through the first 3 months. After the end of month 3, bowing and prostration on the floor may be considered if kneeling on a soft mat is comfortable; continue using a chair for prolonged sitting during tashahhud. Ask your religious authority about permissible alternatives.

❤️ 14) When can I resume sexual activity?

Once the wound is closed, sexual activity in a comfortable position can usually resume during weeks 3–6. Avoid deep knee bending or placing body weight on it. Stop the movement and change position if pain occurs.

🧳 15) When can I travel or fly?

During prescribed clot-prevention treatment, usually the first 4–5 weeks, postpone long flights and journeys lasting several hours if possible. If travel is essential, plan stops to walk, ankle movements, and continued prescribed medication. Do not start extra medicine for travel on your own.

🚲 16) Which sports are suitable after knee replacement?

Walking and stationary cycling, increased gradually with comfortable knee movement, are suitable low-impact activities. For more activity, the wound should be closed and exercise should not increase pain and swelling. The aim is activity you can repeat; a hard start followed by a long pause because of swelling is not progress.

🏀 17) What about running, football, and impact sports?

Regular running, jumping, and contact sports are usually not recommended after knee replacement. They place more load and impact on the artificial joint. Maintain fitness with a low-impact activity that suits your movement and balance.

🧎 18) Can I kneel or sit on the floor?

Kneeling may be possible after the end of month 3 if a soft surface feels comfortable. Sitting cross-legged, prolonged kneeling, and squat toilets are not recommended in this clinic; a chair and seated toilet are more suitable. Do not force the knee to the end of its range to gain more bending.

📐 19) How far will the artificial knee bend?

The American Academy of Orthopaedic Surgeons (AAOS) patient guide describes an average range of motion of around 115 degrees as a usual expectation after total knee replacement. Your bending depends on preoperative movement, tissues, and rehabilitation; very deep bending is not guaranteed. Regular exercise and swelling control help, but painful forced stretching is not the way to improve the range.

🔧 20) How many years does an artificial joint last?

A review published in 2019 found that about 82% of primary total knee replacements in Finnish registry data had not needed revision by 25 years. These are results from operations performed in earlier years, rather than a guarantee for your current prosthesis or freedom from pain. Age, activity, infection, and component loosening affect durability. Regular follow-up and reporting new pain remain important even after years without problems.

✅ Your next step

Pain, limitations, and response to treatment determine when knee replacement is appropriate, rather than an X-ray or age alone. If non-surgical treatment is insufficient, discuss expected benefits, risks, and readiness. Maintaining strength, learning walker use, and arranging help at home ease the start of rehabilitation. Clear goals and realistic expectations help match treatment to your daily needs.

📚 Scientific references

View scientific references

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