Compression-Assisted Arthrocentesis of the Knee as a Quality Improvement Intervention

Abstract

ObjectiveThe present study reports the introduction of mechanical compression of the knee for arthrocentesis as quality improvement intervention in a procedure clinic.Methods430 consecutive symptomatic osteoarthritic knees underwent arthrocentesis followed by corticosteroid injection (1mg/kg of triamcinolone acetonide). The first 215 consecutive knees underwent conventional arthrocentesis and injection; the quality intervention of a mechanical compression brace was introduced, and the next 215 consecutive knees underwent mechanical compression-assisted arthrocentesis follow by injection. Pain scores, arthrocentesis success, fluid yield, time-to-next-intervention, injections/year, and medical costs were measured.ResultsNo serious adverse events occurred in 430 subjects. Diagnostic synovial fluid (≥2 ml) was obtained in 9.3% (20/215) without compression and 40.9% (88/215) with compression (p=0.00001, z for 95% CI= 1.96, Pierson). Mechanical compression was associated with a 231% increase in mean arthrocentesis volume: compression 5.3±11.2 ml, conventional 1.6±6.4 ml (CI of difference 2.0 <3.7< 5.4; p=0.00001). Time-to-next-intervention after compression-assisted arthrocentesis was longer: 6.9±3.5 months compared to conventional: 5.1±2.7 months (p<0.00001, 95% CI of difference 1.2 <1.8< 2.3). Mechanical compression was associated with a reduction in the number of corticosteroid injections administered per year: mechanical compression: 1.7±0.9 injections/year; conventional: 2.4±0.5 injections/year (p<0.00001, 95% CI of difference −0.83 < −0.70< −0.56). Mechanical compression did not increase overall yearly costs associated with management of the symptomatic knee (mechanical compression: $293.30/year/knee, conventional: $373.29/year/knee) (p<0.0001, 95% CI of difference 47 <80< 112).ConclusionsRoutine mechanical compression of the knee for arthrocentesis and injection is an effective bioengineering quality improvement intervention in a procedure clinic.

Extraction of Synovial Fluid from the Non-Effusive Pathologic Knee with Pneumatic Compression

“…Subsequently, the superior knee and suprapatellar bursa were compressed with a pneumatic blood pressure cuff to 100 mg Hg, arthrocentesis was again attempted with marked improved arthrocentesis success. Unlike previous reports that used a specialty compression cuff, the present study demonstrates that a widely available, inexpensive conventional thigh blood pressure cuff can be used to provide circumferential pressure to effectively extract fluid from the non-effusive knee [12,20,21,26,27].…”

“…Extraction of synovial fluid for crystal examination and cellular, immunologic, biomarker and metabolic analysis is presently an important area of clinical care and research integral to current and future joint preservation strategies and therapies [1][2][3][4][5][6][7][8][9][10]12,[22][23][24][25]. Thus, obtaining at least a minimal volume of synovial fluid from a painful or pathologic knee is important diagnostically, prognostically, for accurate injection of therapeutics, and scientifically, especially for research and development of precision arthritis therapies [20][21][22][23][24][25][26][27] In the current study we report significant improvement in terms of arthrocentesis fluid yield and diagnostic success from pneumatic compression of the non-effusive knee (Table 1, Figure 5).…”

“…), the anatomic approach, and technique including image-guidance . However, previous studies have demonstrated a high failure rate of 38% to 68% of conventional arthrocentesis in unselected pathologic knees [1,12,[20][21][22]. This high failure rate of arthrocentesis is primarily due to large proportion of "dry" or non-effusive knees; that is, knees without conventionally extractable fluid resulting in an arthrocentesis failure rate in non-effusive knees ranging between 82 -100% [1,10,19,20].…”

“…As reviewed by Pascual et al indications for aspirating the non-effusive knee are the following: 1) to diagnose crystal-associated disease (gout and pseudogout) during the intercritical period when there is no obvious effusion, 2) to confirm intraarticular needle positioning by synovial fluid return before injecting a joint with a medication, and 3) to obtain synovial fluid for biomarker analysis [1][2][3][4][5][6][7][8][9][10][11][12][22][23][24][25]. As recently reviewed by Kraus et al biomarkers to classify and monitor the pathologic joint are an important area of research and new therapeutics [25].…”

“…For the diagnosis of crystal disease often only a few drops of synovial fluid are required; however, special analyses may require 0.1 ml or more and conventional analysis usually requires at least 2 ml . To obtain adequate synovial fluid yield from the non-effusive knee, ultrasound guidance, stress maneuvers, joint lavage, and external compression may be used to obtain adequate synovial fluid volumes [12,[20][21][22][23][24][25][26][27][28][29].…”