Periarticular needle-based therapies can cause periprosthetic knee infections.

Periarticular needle-based therapies such as dry needling, acupuncture, and genicular nerve radiofrequency ablation are becoming more popular for treatment of knee osteoarthritis. These therapies are also being used after total knee arthroplasty for persistent postoperative pain. Although limited published evidence exists for the risk of periprosthetic joint infection after these procedures, we describe one case of periprosthetic joint infection developing shortly after dry needling and another case developing shortly after genicular nerve blocks. We present details of these 2 cases along with a review of the literature regarding the use of periarticular needle-based therapies after total knee arthroplasty.

Systemic Safety of Liposomal Bupivacaine in Simultaneous Bilateral Total Knee Arthroplasty.

BACKGROUND: Intraoperative periarticular injections (PAIs) with local anesthetic are an important component of multimodal pain control in total joint arthroplasty. Liposomal bupivacaine is an extended-release formulation of bupivacaine designed to provide extended pain relief, approved for use in a single surgical site. The systemic safety profile for use in simultaneous bilateral TKA (bTKA) with a full dose in each knee has not been evaluated. The purpose of this study was to determine the safety and pharmacokinetics of bilateral full-dose PAI liposomal bupivacaine in the blood collected in patients undergoing simultaneous bTKA. METHODS: In this prospective study, patients had an identical PAI consisting of 20 cc of liposomal bupivacaine (266 mg), 30 cc of 0.25% bupivacaine (75 mg) with epinephrine, and 10 cc of normal saline injected into each knee during bTKA. Blood samples were collected at predefined intervals until patient discharge. No exogenous bupivacaine was administered. Pharmacokinetic evaluations were subsequently performed and compared to bupivacaine toxicity levels. Patients were monitored for adverse events related to anesthetic toxicity (cardiac and neurologic). RESULTS: Fifteen patients (mean age, 60.7 years; range, 57-64 years) were enrolled in the study. The mean peak level (Cmax) was 0.8 µg/mL (range, 0.4-1.2 µg/mL). All patients were well below the reported systemic cardiac and toxicity levels reported as 2-4 µg/mL. There were no reported cardiac and neurotoxic events in any patients. CONCLUSION: The use of full-dose PAI with liposomal bupivacaine placed into each knee during simultaneous bTKA is safe with systemic bupivacaine levels well below reported cardiac and neurotoxic levels.

Poor Outcomes of Irrigation and Debridement in Acute Periprosthetic Joint Infection With Antibiotic-Impregnated Calcium Sulfate Beads.

BACKGROUND: One proposed strategy to increase the success of irrigation and debridement with implant retention for the treatment of acute periprosthetic joint infection (PJI) is the use of dissolvable antibiotic-impregnated calcium sulfate beads to provide a local depot of antibiotics. The purpose of this study was to evaluate the outcome of such an approach. METHODS: Thirty-two patients with acute hematogenous (18 patients; 1 bilateral) or acute postoperative (14 patients) PJIs who underwent irrigation and debridement with implant retention and addition of antibiotic-impregnated calcium sulfate beads were retrospectively reviewed. PJI followed 27 total knee arthroplasties and 6 total hip arthroplasties. The most common infecting organisms were methicillin-sensitive Staphylococcus aureus (13 of 33) and Streptococcus (9 of 33). The primary outcome parameter was recurrence of infection according to the Musculoskeletal Infection Society criteria. Patients were followed up for a minimum of 3 months or until failure. RESULTS: At a mean of 12.7 months (range, 3-30 months), 16 of the 33 patients failed (48%). Acute hematogenous and acute postoperative PJI had similar failure rates at 47% and 50%, respectively (P = .88). Seven failures required a 2-stage exchange, while 8 patients were treated with chronic antibiotic suppression, being unwilling or unable to undergo further surgical intervention. CONCLUSION: The addition of antibiotic-impregnated calcium sulfate beads does not appear to improve outcomes of irrigation and debridement with implant retention in the setting of acute hematogenous or acute postoperative PJI. Given the short follow-up in this report, this represents a best-case scenario and the overall failure rate may be higher with further follow-up.

What Is the Benefit of Tranexamic Acid vs Reinfusion Drains in Total Joint Arthroplasty?

We sought to compare the efficacy and cost of reinfusion drains vs tranexamic acid (TA) in primary total joint athroplasty (TJA) patients. We randomized 186 primary TJAs (71 hips, 115 knees) to standard drains (61/186), autologous reinfusion drains (60/186), or single dose (20 mg/kg) of TA (65/186). There was a statistically significant (P < .0001) less drop in hemoglobin levels (2.98 mg/dL; range, 0.5-6.10) in the TA group compared with standard drains (P < .0001) and reinfusion drains (P < .0061). There was no significant difference in transfusion rates. At $581.89, the unit cost of the reinfusion system is substantially higher than the standard drain ($7.56) and TA ($35.91/g). The results of this randomized controlled trial demonstrate that TA is more efficacious and provides cost savings compared with reinfusion drains as a blood management tool for TJA.

Unicompartmental knee arthroplasty in octogenarians: survival longer than the patient.

The unicompartmental knee arthroplasty continues to gain popularity as a viable treatment option for disease isolated to one compartment. It has been reported to provide decreased perioperative morbidity, faster recovery, and excellent long- term survival. We hypothesized that the unicompartmental knee arthroplasty is durable enough to benefit octogenarians, and may be a viable alternative to total knee arthroplasty as the definitive treatment of localized arthritis in this age group. From 1978 to 1990, 28 consecutive patients (38 knees) 80 years or older had unicompartmental knee arthroplasties. Knee Society knee and function scores improved at an average of 4 years followup (range, 2-9 years). Family members reported 90% patient satisfaction regarding expectations and desire to have the surgery again. The mean postoperative survival was 11.9 years, and only two of the 38 knees (5%) required surgical intervention. At final followup, 25 patients had died with all but one patient having the index unicompartmental knee arthroplasty in place and functioning well. Of the three living patients, one required surgery for femoral component fracture 10 years after the index procedure. The unicompartmental knee arthroplasty can be expected to provide reliable and durable results in certain octogenarians, and should be regarded as a definitive treatment option in appropriated selected patients of this age group.