# Total Knee Replacement > Citation bundle for Total Knee Replacement on The Treatment Registry. > URL: https://thetreatmentregistry.com/procedures/knee-replacement > Bundle URL: https://thetreatmentregistry.com/api/citations/procedures/knee-replacement - Category: orthopaedic - Average recovery: 42 days - Typical sessions: 1 - Price range (USD international): $5,000–$20,000 ## Description Total knee replacement (total knee arthroplasty) involves replacing damaged cartilage and bone in the knee joint with metal and plastic components. It is typically performed for severe osteoarthritis or rheumatoid arthritis that has not responded to conservative treatment. The procedure requires significant physiotherapy during recovery. ## Overview Total knee arthroplasty is a major orthopaedic procedure performed under spinal or general anaesthesia, lasting approximately ninety minutes to two hours. The surgeon removes the damaged articular surfaces of the femur and tibia and resurfaces them with metal components fixed to the bone with bone cement or press-fit techniques. A plastic (polyethylene) tibial insert provides the bearing surface, and the patella may be resurfaced depending on the surgeon's preference and the extent of patellar involvement. Alignment is achieved using conventional mechanical guides, computer navigation, or robotic-assisted systems. Candidacy is based on radiographic evidence of severe joint space narrowing with corresponding functional limitation unresponsive to weight loss, physiotherapy, analgesics, and intra-articular injections. Age and activity level influence implant selection: highly active patients may place excessive demands on bearing surfaces, whereas very elderly or low-demand patients may be suitable candidates at lower symptom thresholds. Patients with significant comorbidities (poorly controlled diabetes, severe cardiac disease, active infection) require optimisation before surgery. Ambulation begins on the day of or the day after surgery, and the focus of in-patient physiotherapy is restoring range of motion and safe independent mobility. Discharge to a rehabilitation facility or home typically occurs at three to five days. Achieving ninety degrees of flexion by six weeks is a commonly used milestone. Full recovery — including return to comfortable walking on most surfaces — typically takes three to six months, with ongoing improvement possible over twelve months. Patients with poor pre-operative flexibility or significant stiffness face more challenging rehabilitation. ## Peer-reviewed outcome rates - **Complication rate:** 5.00% (range 2.00–8.00%) — from 2 cited sources - **Revision rate:** 5.00% (range 2.00–10.00%) — from 1 cited source - **Mortality rate:** 0.50% (range 0.20–1.00%) — from 1 cited source ## Common risks - Deep vein thrombosis or pulmonary embolism - Infection (prosthetic joint infection is serious and may require revision) - Stiffness or limited range of motion - Implant loosening over time - Nerve or blood vessel damage - Persistent pain despite technically successful surgery ## FAQs ### How long does a knee replacement last? Modern knee implants are designed to last fifteen to twenty-five years in most patients, with published data showing survival rates above ninety per cent at fifteen years. Factors that reduce longevity include high activity levels, obesity, and younger age at the time of surgery. ### Will I be able to kneel after a knee replacement? Many patients can kneel after a knee replacement, though it often feels uncomfortable due to the altered sensation from the implant. Most implant designs are compatible with kneeling, but it is advisable to confirm with the surgeon and to use a cushion to reduce pressure on the implant surface. ### What are the alternatives to knee replacement? For patients not yet ready for replacement surgery, alternatives include physiotherapy and exercise programmes, weight loss, anti-inflammatory medications, corticosteroid or hyaluronic acid injections, and partial knee replacement for isolated compartment disease. These delay rather than eliminate the eventual need for replacement in severe arthritis. ### How painful is recovery from knee replacement? Pain in the first few days is managed with a combination of spinal anaesthesia, nerve blocks, and analgesics. Most patients describe the recovery as challenging but manageable. By six weeks, the majority report that their pain level is significantly lower than before surgery. ### Will I set off airport security with a knee implant? Metal knee implants frequently trigger airport security scanners. Patients are advised to inform security staff and carry documentation of the implant — most manufacturers provide an implant identification card. Body scanners in modern airports may not trigger an alarm, but metal detectors generally will. ### Can I have both knees replaced at the same time? Simultaneous bilateral knee replacement is technically feasible and reduces overall recovery time, but carries higher rates of blood transfusion, cardiovascular complications, and mortality compared with staged procedures. Most surgeons recommend replacing one knee at a time, spacing the operations by three to six months. ### Is physiotherapy really necessary after knee replacement? Yes — physiotherapy is a critical determinant of the final range of motion and functional outcome. Patients who do not engage with rehabilitation consistently achieve poorer results in terms of knee flexion, strength, and satisfaction. Regular physiotherapy for at least three months post-operatively is strongly recommended. ### What sports can I do after a knee replacement? Low-impact activities such as walking, swimming, cycling, and golf are generally well tolerated and encouraged. High-impact sports such as running, football, and skiing place excessive stress on the implant and are generally advised against to preserve implant longevity. Most patients significantly increase their activity level compared with before surgery. ## Alternative treatments - **Partial knee replacement (unicompartmental)** — When osteoarthritis is confined to a single compartment, preserves more bone and ACL. - **High tibial osteotomy** — Joint-preserving realignment for younger active patients with isolated medial-compartment disease. - **Hyaluronic acid or corticosteroid injection** — Conservative symptomatic management; modest and time-limited relief. - **Physiotherapy + weight management** — Evidence-based first-line management; can defer surgery by years in some patients. ## Sources - [AAOS — Surgical Management of Osteoarthritis of the Knee Clinical Practice Guideline](https://www.aaos.org/quality/quality-programs/lower-extremity-programs/surgical-management-of-osteoarthritis-of-the-knee/) — American Academy of Orthopaedic Surgeons (accessed 2026-05-09) - [National Joint Registry for England, Wales, Northern Ireland and the Isle of Man — Annual Report](https://www.njrcentre.org.uk/njrcentre/Reports-Publications-and-Minutes/Annual-reports) — National Joint Registry (accessed 2026-05-09) - [RCoA — Guidelines for the Provision of Anaesthetic Services (GPAS)](https://www.rcoa.ac.uk/standards-of-clinical-practice) — Royal College of Anaesthetists (accessed 2026-05-09) - [NICE NG89 — Venous thromboembolism in over 16s: reducing the risk of hospital-acquired DVT and PE](https://www.nice.org.uk/guidance/ng89) — National Institute for Health and Care Excellence (accessed 2026-05-09)