These guidelines are intended for use by infectious disease specialists, orthopedists, and other healthcare professionals who care for patients with prosthetic joint infection (PJI). They include evidence-based and opinion-based recommendations for the diagnosis and management of patients with PJI treated with debridement and retention of the prosthesis, resection arthroplasty with or without subsequent staged reimplantation, 1-stage reimplantation, and amputation.

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Diagnosis and Management of Prosthetic Joint Infection: Clinical Practice Guidelines by the Infectious Diseases Society of America

Prosthetic joint infection (PJI) is a tremendous burden for individual patients as well as the global health care industry. While a small minority of joint arthroplasties will become infected, appropriate recognition and management are critical to preserve or restore adequate function and prevent excess morbidity. In this review, we describe the reported risk factors for and clinical manifestations of PJI. We discuss the pathogenesis of PJI and the numerous microorganisms that can cause this devastating infection. The recently proposed consensus definitions of PJI and approaches to accurate diagnosis are reviewed in detail. An overview of the treatment and prevention of this challenging condition is provided.

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Prosthetic Joint Infection

Critical-sized defects in bone, whether induced by primary tumor resection, trauma, or selective surgery have in many cases presented insurmountable challenges to the current gold standard treatment for bone repair. The primary purpose of a tissue-engineered scaffold is to use engineering principles to incite and promote the natural healing process of bone which does not occur in critical-sized defects. A synthetic bone scaffold must be biocompatible, biodegradable to allow native tissue integration, and mimic the multidimensional hierarchical structure of native bone. In addition to being physically and chemically biomimetic, an ideal scaffold is capable of eluting bioactive molecules (e.g., BMPs, TGF-betas, etc., to accelerate extracellular matrix production and tissue integration) or drugs (e.g., antibiotics, cisplatin, etc., to prevent undesired biological response such as sepsis or cancer recurrence) in a temporally and spatially controlled manner. Various biomaterials including ceramics, metals, polymers, and composites have been investigated for their potential as bone scaffold materials. However, due to their tunable physiochemical properties, biocompatibility, and controllable biodegradability, polymers have emerged as the principal material in bone tissue engineering. This article briefly reviews the physiological and anatomical characteristics of native bone, describes key technologies in mimicking the physical and chemical environment of bone using synthetic materials, and provides an overview of local drug delivery as it pertains to bone tissue engineering is included.

https://aiche.onlinelibrary.wiley.com/doi/pdf/10.1002/btpr.246

Bone tissue engineering: A review in bone biomimetics and drug delivery strategies

BackgroundPlatelet-rich fibrin matrices release a natural mixture of growth factors that play central roles in the complex processes of tendon healing.HypothesisApplication of autologous platelet-rich matrices during Achilles tendon surgery may promote healing and functional recovery.Study DesignCase-control study and descriptive laboratory study; Level of evidence, 3.MethodsTwelve athletes underwent open suture repair after complete Achilles tendon tear. Open suture repair in conjunction with a preparation rich in growth factors (PRGF) was performed in 6 athletes and retrospectively compared with a matched group that followed conventional surgical procedure. The outcomes were evaluated on the basis of range of motion, functional recovery, and complications. Achilles tendons were examined by ultrasound at 50 ± 11 months in retrospective controls and 32 ± 10 months in the PRGF group. In the laboratory portion of the study, PRGF treatment was characterized by the number of platelets and concentration of ins...

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Comparison of Surgically Repaired Achilles Tendon Tears Using Platelet-Rich Fibrin Matrices

https://www.eng.tau.ac.il/~meitalz/Articles/E4.pdf

Antibiotic-eluting medical devices for various applications

Background: There is a paucity of data on the treatment of femoral neck fractures in young patients. The purpose of the present study was to review the results and complications associated with the treatment of femoral neck fractures with internal fixation in a large consecutive series of young patients.

Methods: Between 1975 and 2000, eighty-three femoral neck fractures in eighty-two consecutive patients who were between fifteen and fifty years old were treated with internal fixation at our institution. Two patients died, and eight were lost to follow-up. Seventy-three fractures were followed until union, until conversion to hip arthroplasty, or for a minimum of two years; the mean duration of follow-up was 6.6 years. Fifty-one of the seventy-three fractures were displaced, and twenty-two were nondisplaced. The results and complications of treatment were retrospectively reviewed, and the effects of fracture displacement, reduction quality, and capsular decompression on outcome were evaluated. Function was assessed by evaluating pain, walking capacity, and the need for gait aids. The mean duration of follow-up for the fifty-seven patients (fifty-eight fractures) who had not undergone early conversion to arthroplasty was 8.1 years.

Results: Fifty-three (73%) of the seventy-three fractures healed after one operation and were associated with no evidence of osteonecrosis of the femoral head. Osteonecrosis developed in association with seventeen fractures (23%), and a nonunion developed in association with six (8%). Four of the six nonunions later healed after a secondary procedure. At the time of the final follow-up, thirteen patients had had a conversion to a total hip arthroplasty because of osteonecrosis (eleven), nonunion (one), or both (one). Five (9.8%) of the fifty-one displaced fractures were associated with the development of nonunion, and fourteen (27%) were associated with the development of osteonecrosis. Three (14%) of the twenty-two nondisplaced fractures were associated with the development of osteonecrosis, and one (4.5%) was associated with the development of nonunion. Eleven (24%) of the forty-six displaced fractures with a good to excellent reduction were associated with the development of osteonecrosis, and two (4%) were associated with the development of nonunion. Four of the five displaced fractures with a fair or poor reduction were associated with the development of osteonecrosis, nonunion, or both.

Conclusions: The ten-year survival rate of the native femoral head free of conversion to total hip arthroplasty was 85%. Osteonecrosis was the main reason for conversion to total hip arthroplasty, but not all patients with osteonecrosis required further surgery. The results of treatment were influenced by fracture displacement and the quality of reduction.

Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Operative treatment of femoral neck fractures in patients between the ages of fifteen and fifty years.

Robotic-assisted orthopedic surgery has been available clinically in some form for over 2 decades, claiming to improve total joint arthroplasty by enhancing the surgeon's ability to reproduce alignment and therefore better restore normal kinematics. Various current systems include a robotic arm, robotic-guided cutting jigs, and robotic milling systems with a diversity of different navigation strategies using active, semiactive, or passive control systems. Semiactive systems have become dominant, providing a haptic window through which the surgeon is able to consistently prepare an arthroplasty based on preoperative planning. A review of previous designs and clinical studies demonstrate that these robotic systems decrease variability and increase precision, primarily focusing on component positioning and alignment. Some early clinical results indicate decreased revision rates and improved patient satisfaction with robotic-assisted arthroplasty. The future design objectives include precise planning and even further improved consistent intraoperative execution. Despite this cautious optimism, many still wonder whether robotics will ultimately increase cost and operative time without objectively improving outcomes. Over the long term, every industry that has seen robotic technology be introduced, ultimately has shown an increase in production capacity, improved accuracy and precision, and lower cost. A new generation of robotic systems is now being introduced into the arthroplasty arena, and early results with unicompartmental knee arthroplasty and total hip arthroplasty have demonstrated improved accuracy of placement, improved satisfaction, and reduced complications. Further studies are needed to confirm the cost effectiveness of these technologies.

Robotics in Arthroplasty: A Comprehensive Review.

The purpose of this study was to assess the systemic safety and potential adverse effects of using a high-dose antibiotic-impregnated cement spacer after resection arthroplasty of an infected total knee replacement. Between October 2000 and December 2002, 36 knees (34 patients) had a resection arthroplasty of an infected total knee prosthesis with placement of a high-dose antibiotic impregnated cement spacer. There were 24 men and 10 women with a mean age of 66.5 years (range, 48-84 years). All spacers placed contained an average of 3.4 batches of cement with an average total dose of 10.5 g of vancomycin (range, 3-16 g) and 12.5 g of gentamicin (range, 3.6-19.2 g). All patients were followed up post-operatively until reimplantation for evidence of renal failure. The preoperative creatinine ranged from 0.7 to 1.8 mg/dL. All patients were concomitantly treated with 6 weeks of intravenous organism-specific antibiotics. One patient with normal preoperative renal function (Cr 0.7 mg/dL) had a perioperative 1-day transient rise in serum creatinine (1.7 mg/dL) postoperatively that subsequently normalized. No patients showed any clinical evidence of acute renal insufficiency, failure, or other systemic side effects of the antibiotics. Treatment of patients with an infected total knee arthroplasty with high-dose vancomycin and gentamicin antibiotic spacers seems to be clinically safe.

Systemic safety of high-dose antibiotic-loaded cement spacers after resection of an infected total knee arthroplasty.

The orthopedic community has seen the COVID-19 pandemic decimate elective surgical volumes in most geographies. Patients and essential workers, such as health care providers, remain rightfully concerned about how to appropriately begin to return to work and community activity in a safe and responsible manner. Many believe that testing for the presence of antibodies on a widespread scale could help drive evidence-based decision-making, both on an individual and societal scale. Much information, and an equal amount of misinformation, has been produced on antibody testing. Education about the role and science of such testing is critically important for programs to be effectively understood and managed.

Understanding Antibody Testing for COVID-19.

This study determined if robotic-arm assisted total knee arthroplasty (RATKA) allows for more accurate and precise bone cuts and component position to plan compared with manual total knee arthroplasty (MTKA). Specifically, we assessed the following: (1) final bone cuts, (2) final component position, and (3) a potential learning curve for RATKA. On six cadaver specimens (12 knees), a MTKA and RATKA were performed on the left and right knees, respectively. Bone-cut and final-component positioning errors relative to preoperative plans were compared. Median errors and standard deviations (SDs) in the sagittal, coronal, and axial planes were compared. Median values of the absolute deviation from plan defined the accuracy to plan. SDs described the precision to plan. RATKA bone cuts were as or more accurate to plan based on nominal median values in 11 out of 12 measurements. RATKA bone cuts were more precise to plan in 8 out of 12 measurements (p ≤ 0.05). RATKA final component positions were as or more accurate to plan based on median values in five out of five measurements. RATKA final component positions were more precise to plan in four out of five measurements (p ≤ 0.05). Stacked error results from all cuts and implant positions for each specimen in procedural order showed that RATKA error was less than MTKA error. Although this study analyzed a small number of cadaver specimens, there were clear differences that separated these two groups. When compared with MTKA, RATKA demonstrated more accurate and precise bone cuts and implant positioning to plan.

/pdf/robotic-arm-assisted-total-knee-arthroplasty-demonstrated-2iwqknntpk.pdf

David J. Jacofsky

Papers

Operative treatment of femoral neck fractures in patients between the ages of fifteen and fifty years.

Robotics in Arthroplasty: A Comprehensive Review.

Systemic safety of high-dose antibiotic-loaded cement spacers after resection of an infected total knee arthroplasty.

Understanding Antibody Testing for COVID-19.

Robotic-Arm Assisted Total Knee Arthroplasty Demonstrated Greater Accuracy and Precision to Plan Compared with Manual Techniques.