Infection of total knee arthroplasty

Recommended as an option for severe knee osteoarthritis (OA) for patients who have not responded adequately to conservative treatment (exercise, NSAIDs, corticosteroid injections), in order to potentially delay total joint replacement. Higher quality studies have shown the magnitude of improvement to be modest at best. While medial and/or lateral compartment OA is a recommended indication, there is insufficient evidence for other conditions including patella-femoral arthritis, chondromalacia patella, patella-femoral syndrome (kneecap pain), or osteochondritis dissecans.

7. Painful failed total knee arthroplasty

- In patients with chronic joint infections that have led to severe knee damage.

ODG Indications for Surgery™ -- Knee arthroplasty:

Pollock M, Somerville L, Firth A, Lanting B. Total Hip , Total KneeArthroplasty, and Unicompartmental Knee Arthroplasty: A Systematic Review ofthe Literature. . 2016 Dec27; 4(12).

Criteria for knee joint replacement:

IssaK, Kapadia BH, Kester M, Khanuja HS, Delanois RE, Mont MA. Clinical, objective,and functional outcomes of to treat knee stiffness following arthroplasty. . 2014 Mar; 29(3):548-52.

- Patients with rheumatoid arthritis and multiple joint involvement tolerate knee fusions poorly.
(2) Revision total knee arthroplasty (TKA) would be a better indication than primary TKA, but either OK if #1 applies.

New trends in instrumented knee prostheses - …

Insoles can reduce pain among patients with knee OA. () See also ; and . Increased joint loading significantly increases the risk of osteoarthritis progression, but is amenable to change using insoles or footwear, and insoles and footwear offer great potential as simple, inexpensive treatment strategies for knee osteoarthritis. () Lateral wedge insoles can cause some discomfort and are effective primarily for patients with early stage OA. Lateral wedge insoles (a wedge inclined along the outside of the foot) reduce the knee adduction moment during walking. In patients with OA, the use of lateral wedge insoles of between 5° and 15° inclination reduce peak knee adduction moments by between 4% and 14% during walking compared with the corresponding values either without insoles or wearing even-thickness control insoles and also led to immediate reductions in pain during walking. Extension of the lateral wedge along the entire length of the foot is important, since the knee adduction moment is only reduced with a full-length insole, not with a lateral wedge covering just the heel region. Lateral wedge insoles reduce knee adduction moments in patients with early to mild OA ( grades 1-2), but not in patients with moderate-to-severe OA (grades 3-4), and these insoles were ineffective in patients with the most advanced stages of OA. Considering their immediate positive influence on the knee adduction moment and clinical utility, lateral wedge insoles should be considered as a potentially useful intervention, especially for patients with early OA. ()

Total knee arthroplasty (TKA)

Prosthetic-Joint Infections — NEJM

Diagnostic performance of MR imaging of the menisci and cruciate ligaments of the knee is different according to lesion type and is influenced by various study design characteristics. Higher magnetic field strength modestly improves diagnostic performance, but a significant effect was demonstrated only for anterior cruciate ligament tears. () () A systematic review of prospective cohort studies comparing MRI and clinical examination to arthroscopy to diagnose meniscus tears concluded that MRI is useful, but should be reserved for situations in which further information is required for a diagnosis, and indications for arthroscopy should be therapeutic, not diagnostic in nature. () This study concluded that, in patients with nonacute knee symptoms who are highly suspected clinically of having intraarticular knee abnormality, magnetic resonance imaging should be performed to exclude the need for arthroscopy. () In most cases, diagnosing osteoarthritis with an MRI is both unnecessary and costly. Although weight-bearing X-rays are sufficient to diagnose osteoarthritis of the knee, referring physicians and some orthopedic surgeons sometimes use magnetic resonance imaging (MRI) either with or instead of weight bearing X-rays for diagnosis. For total knee arthroplasty (TKA) patients, about 95% to 98% of the time they don't need an MRI. Osteoarthritis patients often expect to be diagnosed with MRIs, and this demand influences MRI use. Average worker's compensation reimbursement is also higher for the knee MRI ($664) than for the knee X-rays ($136). () Repeat MRIs are recommended if need to assess knee cartilage repair tissue. In determining whether the repair tissue was of good or poor quality, MRI had a sensitivity of 80% and specificity of 82% using arthroscopy as the standard. ()

(3) Open reduction and internal fixation of tibial plateau or distal femur fractures involving the knee joint ()

Optimization of an instrumented knee implant …

The knee adduction moment has an integral role in the development and progression of knee OA. A number of conservative biomechanics-based interventions can reduce the knee adduction moment effectively via different mechanisms. Many of these conservative biomechanical strategies could be employed in early stage OA and might help to prevent and/or delay disease progression. Valgus knee braces secured around the thigh and lower leg and worn throughout the day are a conservative treatment strategy for patients with medial knee OA. The underlying rationale for use of a valgus knee brace is the application of a valgus moment (knee abduction moment) to the knee joint, which could reduce the knee adduction moment during walking and unload the medial compartment of the knee. Valgus knee braces reduce the net knee adduction moment during walking in healthy young adults and in patients with medial knee OA. Pain is a symptom of knee joint OA, and a valgus knee brace substantially reduces pain immediately upon use, and after continuous wear for durations ranging between 2 weeks and 12 months. Improvements in function have also been reported in patients with OA following valgus knee bracing for durations of between 6 months and 12 months. Although valgus bracing achieves effective unloading of the medial compartment of the knee and offers potential for improving the clinical outcome in patients with knee OA, the success of this intervention relies upon the patient being prepared to wear the knee brace continually. Valgus knee braces are bulky, potentially uncomfortable and might not be a practical daily solution for many patients. () Knee bracing after ACL reconstruction appears to be largely useless, according to a systematic review. Postoperative bracing did not protect against re-injury, decrease pain, or improve stability. ()