Antibiotic cement coating in orthopedic surgery: a systematic review of reported clinical techniques.

BACKGROUND: Antibiotic-containing cement and bone graft substitute-coated orthopedic implants provide the advantages of simultaneous local antibiotic delivery and internal stable fixation, aiding in both infection eradication and osseous healing. Standardized protocols pertaining to implant coating techniques in various clinical and particularly intraoperative settings are scarce, and available literature is limited. This systematic review aims to provide a summary of the available current literature reporting on custom-made coating techniques of orthopedic implants, indications, outcomes, and associated complications in clinical use. METHODS: A systematic search of the literature in PubMed, Medline, Embase, and Cochrane Library databases was performed in accordance with PRISMA guidelines. Articles reporting specifically on custom-made coating techniques of orthopedic implants in a clinical setting were eligible. RESULTS: A total of 41 articles with a cumulative total number of 607 cases were included. Indications for treatment mostly involved intramedullary infections after previous plate osteosynthesis or nailing. A variety of implants ranging from intramedullary nails, plates, wires, and rods served as metal cores for coating. Polymethylmethacrylate (PMMA) bone cement was most commonly used, with vancomycin as the most frequently added antibiotic additive. Chest tubes and silicone tubes were most often used to mold. Common complications are cement debonding and breakage of the metallic implant. CONCLUSION: Adequate coating techniques can reduce the burden of treatment and be associated with favorable outcomes. Lack of general consensus and heterogeneity in the reported literature indicate that the perfect all-in-one implant coating method is yet to be found. Further efforts to improve implant coating techniques are warranted. LEVEL OF EVIDENCE: III.

[Polymethyl methacrylate cement coating of intramedullary implants : A new technique for revision surgery with the example of a temporary knee arthrodesis. Video article]. / Polymethylmethacrylat-Zementbeschichtung intramedullärer Implantate : Eine neue Technik für die Revisionschirurgie am Beispiel einer temporären Kniegelenkarthrodese. Videobeitrag.

BACKGROUND: The coating of intramedullary rods with polymethyl methacrylate (PMMA) bone cement containing antibiotics ensures a high concentration of antibiotics locally and stability in fractures that are not yet consolidated. However, bone cement can detach when the implant is removed and remain in the medullary cavity of the long bones. CASE REPORT: After a periprosthetic knee infection, a 56-year-old patient suffered from a painful reinfection of Staphylococcus epidermidis. This was an indication for removal of the prosthesis. OPERATION: After soft-tissue debridement and synovectomy, rotating hinge prosthesis that had been inserted was removed. Humeral nails coated with PMMA cement containing antibiotics were used as temporary intramedullary implants. To prevent the bone cement from detaching when the implant was removed and cement residue from remaining in the bone, the humeral nails were reinforced with cerclage wire. The coated implant was then press fit into the medullary cavity.

Treatment of proximal fifth metatarsal fractures with an ulna hook plate.

INTRODUCTION: Fractures of the base of the fifth metatarsal bone present one of the commonest fractures of the metatarsal bones. Conventionally intramedullary screws and tension band wiring have been used as internal fixation methods. Lately hook plates have also served as an alternative fixation method. We hereby report on our experience with the hook plate used in treating fractures of the proximal fifth metatarsal. METHODS: 21 patients treated with the hook plate for proximal fifth metatarsal fractures were assessed clinically and radiologically. RESULTS: Average time to union in primarily treated fractures (n=18) was 7.7 weeks (range 4.5-16 weeks). Average time to return of activities of daily living (ADLs) was 10.3 weeks (range 4.5-37 weeks). The average AOFAS midfoot score was 30.4 preoperatively and 95.2 postoperatively (p<0.01). CONCLUSION: The ulna hook plate presents a suitable and adequate method of osteosynthesis used to primarily treat proximal fifth metatarsal fractures requiring surgical intervention with satisfactory post-operative outcomes.

Limb-saving Knee Arthrodesis with a Silver-coated Arthrodesis Rod in a Patient with Aspergillus Osteomyelitis of the Knee.

Aspergillus osteomyelitis can be a very debilitating disease with an associated mortality of up to 25%. Silver is well known for its broad antimicrobial properties including activity against fungi and the coating of orthopaedic implants with silver has been reported to be successful in complex cases. We report for the first time on a complicated case of Aspergillus osteomyelitis affecting the left knee in a patient with a chronic lymphoid leukaemia treated with appropriate surgical debridement, local and systemic antibiotic and antimycotic therapy, as well as staged surgical treatment with final limb-saving arthrodesis by using a custom-made microsilver coated arthrodesis rod. How to cite this article: Ismat A, Alt V, Heiss C, et al. Limb-saving Knee Arthrodesis with a Silver-coated Arthrodesis Rod in a Patient with Aspergillus Osteomyelitis of the Knee. Strategies Trauma Limb Reconstr 2020;15(2):121-125.

Computed tomography for managing periprosthetic femoral fractures. A retrospective analysis.

BACKGROUND: Periprosthetic fractures (PPF) present a common cause for revision surgery after arthroplasty. The choice of performing either an osteosynthesis or revision arthroplasty depends on the orthopedic implant anchored and loosening. Standard diagnostics include x-ray imaging. CT is usually performed to confirm implant loosening in case of ambiguous diagnosis on standard x-ray imaging. This study aimed to examine the role of CT as a diagnostic modality and its implications for treatment planning and outcome. METHODS: Patients treated for PPF from January 2010 to February 2018 were included. X-ray and CT reports were analyzed to assess implant loosening. The planning for surgery and the final surgical treatment were evaluated. In addition, patient characteristics were analyzed and compared between patients with and without additional CT as a preoperative diagnostic procedure. RESULTS: Seventy-five patients were eligible for the study. X-ray imaging was performed in 90.7% of cases. CT was performed in 60% of the cases as part of the preoperative diagnostic. A clear statement on implant stability or loosening could not be made in 69.1% after X-ray imaging and in 84.4% following CT imaging. Revision arthroplasty for loosened femoral prosthesis components was necessary in 40% of cases. No difference could be determined comparing patients with X-ray imaging to those with X-ray and additional CT. In both groups, operative treatment did not deviate from the preoperative planning. DISCUSSION: In two thirds of the conventional radiographic findings, no reliable evaluation of implant loosening was possible in femoral PPFs. Intriguingly, additional CT did not improve the evaluation of implant loosening. Nonetheless, CT scans are often performed if loosening assessment is unclear on regular radiographs. This fact can explain the bias CT results in comparison to regular radiography. However, software-supported CT diagnosis could help to adequately answer the question of loosened implants in PPF in the near future. Since the diagnosis of fracture and their morphology assessment is currently adequately performed using X-rays, CT shall not be considered as the gold standard.

Do Systemic Factors Influence the Fate of Nonunions to Become Atrophic? A Retrospective Analysis of 162 Cases.

INTRODUCTION: Nonunions are a challenge for orthopedic surgeons. In hypertrophic nonunions, improvement of mechanical stability usually is the satisfactory treatment, whereas in atrophic nonunions improvement of the biological environment is most important. However, scientific evidence revealed that "avital" nonunions are not avascular and fibrous tissue contains cells with osteogenic potential. To find out if systemic factors suppress this intrinsic potential in atrophic nonunions, this study compares characteristics of hypertrophic with atrophic nonunion patients. METHODS: We analyzed medical records of 162 surgically treated patients suffering from aseptic long bone nonunions. Atrophic and hypertrophic nonunions were distinguished by absence or presence of callus and calcification in the fracture gap. Mechanical implant loosening and patient characteristics such as age, gender, and body mass index were assessed. Fracture classification according to AO/OTA, open and closed fractures, and osteosynthesis were recorded. In addition, comorbidities and allergies between both groups were compared. RESULTS: A higher number of hypertrophic nonunion patients were male with often allergies. Hypertrophic nonunion occurred more often after intramedullary nailing compared to atrophic nonunions. Atrophic nonunion patients being nonallergic were significantly older than nonallergic patients suffering from hypertrophic nonunions. In both atrophic and hypertrophic nonunion patients, age was lower in patients with accompanying injuries compared with age of patients with isolated fractures. CONCLUSION: Systemic factors influence development of nonunion types. In nonallergic patients, atrophic nonunions occur more often in the elderly. This manuscript is a first step to identify different factors which might influence the nature of nonunion. To enable nonunion treatment which is tailored to individual patient characteristics, further prospective studies with more sophisticated research methods are necessary.