Which tests would the nurse perform to detect the presence of fluid inside the knee joint
|
Overview Show BackgroundAspiration of a joint (arthrocentesis) with subsequent analysis of the synovial fluid is a critical component in diagnosing arthritis. [1, 2] Analysis of the joint fluid can differentiate an inflammatory arthritis from a noninflammatory arthritis. A definitive diagnosis of crystalline arthritis or septic arthritis can be made only by means of joint aspiration. Joint aspiration is a relatively quick and inexpensive procedure to perform. It can be done in an office setting or in a hospital. No particular certification is required to perform arthrocentesis; it can be done by any physician, physician’s assistant, or advance practice nurse who has the appropriate training and equipment. Initial analysis of the fluid can be performed in the office with the use of a polarized light microscope.  IndicationsJoint aspiration should be considered for any patient with an inflamed joint or joints who does not have an established diagnosis. Inflamed joints are recognized by being red, warm, tender, swollen, and painful to bend. A joint presenting as acute monoarthritis should always be aspirated if infection is suspected upon clinical evaluation. Patients with preexisting arthritis (eg, rheumatoid arthritis or gout) are at increased risk for the development of septic arthritis. Therefore, aspiration must be performed whenever there is suspicion of an infected joint in patients with known arthritis. Repeated aspirations can be part of the management of a septic joint to relieve discomfort and prevent joint damage. Aspiration can be considered in cases of hemarthrosis to prevent adhesions. Aspiration can be performed immediately prior to injecting intra-articular medications such as corticosteroids to improve efficacy. As a rule, if joint aspiration is being considered, it should probably be performed. According to Infectious Diseases Society of America (IDSA) guidelines on management of prosthetic joint infection (PJI), diagnostic arthrocentesis should be performed for any suspected acute PJI unless the diagnosis is clinically evident, surgery is planned, and antibiotics can safely be withheld preoperatively. [3] It is also advised in patients with a chronic painful prosthesis who have unexplained elevations of erythrocyte sedimentation rate or C-reactive protein level or in whom PJI is clinically suspected (though it may not be necessary in all cases). In this setting, synovial fluid analysis should include a total cell count and differential leukocyte count, as well as culture for aerobic and anaerobic organisms. [3] A crystal analysis can also be performed if clinically indicated. Repeat aspiration may be warranted in joint-replacement patients with conflicting clinical data and a prior history of PJI, with suspected adverse local tissue reaction, or with high clinical suspicion of infection. [4, 5] ContraindicationsNo strict contraindications for arthrocentesis are recognized; however, caution is advised in certain situations. A needle should not be passed through an area of infection (eg, overlying cellulitis) before entering a joint, because seeding infection into the joint capsule may occur. Patients who are anticoagulated or have a bleeding diathesis (eg, hemophilia or thrombocytopenia) are at increased risk for hemarthrosis. It has been recommended that when possible, aspiration should be delayed until the coagulopathy is reversed, and that when a delay is not possible, the physician should be prepared to treat bleeding (eg, with appropriate factor concentrates in a hemophiliac patient). However, some studies have found arthrocentesis to be safe in patients receiving anticoagulant therapy. [6, 7, 8] When aspiration of artificial joints is necessary, it is generally handled by an orthopedic surgeon. When a clinical need to aspirate a joint is present in a patient with overlying infection or coagulopathy, the physician must weigh the risks and benefits of aspiration in their decision whether to proceed with arthrocentesis. Technical ConsiderationsAny joint can be aspirated; however, some joint aspirations require the use of ultrasonographic or fluoroscopic guidance. [9] Ultrasonography allows the clinician to confirm the presence of fluid before aspirating. It can also be helpful in aspirating deep or technically difficult joints. The hip joint should be aspirated under ultrasonographic guidance. Joints of the spine, including the sacroiliac joint, should be aspirated under fluoroscopic guidance. Guidance for aspiration is also recommended when blind attempts have failed to access any joint fluid.
Author Specialty Editor Board Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference Disclosure: Nothing to disclose. Chief Editor Vinod K Panchbhavi, MD, FACS, FAOA, FABOS, FAAOS Professor of Orthopedic Surgery, Chief, Division of Foot and Ankle Surgery, Director, Foot and Ankle Fellowship Program, Department of Orthopedic Surgery, University of Texas Medical Branch School of Medicine Vinod K Panchbhavi, MD, FACS, FAOA, FABOS, FAAOS is a member of the following medical societies: American Academy of Orthopaedic Surgeons, American College of Surgeons, American Orthopaedic Association, American Orthopaedic Foot and Ankle Society, Orthopaedic Trauma Association, Texas Orthopaedic Association Disclosure: Serve(d) as a speaker or a member of a speakers bureau for: Styker. Additional Contributors James D Fischkoff, MD Arthritis and Osteoporosis Associates Disclosure: Nothing to disclose. How to test for fluid in knee?Method 2: Assess for fluid by placing one hand superior to the patella and with slight downward pressure milk the suprapatellar pouch which emptys into the knee joint. Next use the other hand to push to push on the patella. If there is an effusion, the patellar will bounce off the underlying bone (patella tap test).
Which test would a nurse perform to confirm a torn meniscus?One of the main tests for meniscus tears is the McMurray test.
Which test would the nurse perform by firmly stroking the medial aspect of the knee three times and tapping the lateral aspect of the knee?Fluid displacement test
This is performed as above, by squeezing excess fluid out of the suprapatellar pouch and then stroking the medial side of the knee joint to displace any excess fluid in the main joint cavity to the lateral side of the joint.
|
