Treatment of stage III-A-1 and III-B-1 periprosthetic knee infection with two-stage exchange arthroplasty and articulating spacer.

The incidence of periprosthetic knee infection is generally low, but the economic impact is great. Treatment should take into account the acuteness of the infection, the overall immune/medical status of the patient, and the local factors at the site of the infection. The aim of this study was to evaluate the two-phase exchange arthroplasty with the use of antibiotic-impregnated articulating spacer, as an alternative treatment of chronic periprosthetic knee infection in patients with minimum systemic and no local compromising factors. Staphylococcus aureus was the most common pathogen followed by Staphylococcus epidermidis and Pseudomonas aeruginosa. Twenty-four patients were treated with this regiment. All of them returned to normal everyday activity and no infection recurrence was noted over a 2- to 10-year follow-up. Excellent long-term results can be achieved for patients staged as III-A-1 and III-B-1 according to the Musculoskeletal Infection Society staging system, when treated with the aforementioned protocol and intravenous antibiotics.

Late postoperative infection following spinal instrumentation: stainless steel versus titanium implants.

Late postoperative infection following instrumented spinal surgery is a clinical entity that has emerged in recent years. The extended surface of the spinal instrumentation in combination with hematogenous seeding or intraoperative inoculation is the main predisposing factor. In order to investigate the contribution of the instrumentation material (stainless steel versus titanium implants) and mechanical loosening, two groups of patients are presented. The first group includes 50 idiopathic scoliotic patients who were treated with first-generation posterior stainless steel spinal segmental multihook instrumentation [Texas Scottish Rite Hospital (TSRH) instrumentation system], and the second group includes 45 similar patients who were treated with newer titanium implants (MOSS MIAMI, XIA, and CD). Follow-up ranged from 3 to 13 years. Six patients from the first group and one patient from the second group presented with late infections 1 to 7 years postoperatively. Common intraoperative findings were excessive inflammatory tissue and some degree of instrumentation loosening and corrosion (stainless steel). Removal of instrumentation in combination with appropriate antibiotics was an effective treatment. Further study with long-term follow-up is necessary in order to understand the exact incidence and pathology of such infections.

Distal leg wear debris mass from a rotating hinged knee prosthesis.

An 18-year-old woman presented with a gradually increasing distal leg mass 8 years after wide resection for an osteosarcoma and reconstruction of the proximal left tibia with a rotating hinged knee megaprosthesis. Open biopsy of the distal leg mass showed necrobiotic tissue, metallosis, fibroblasts, osteoblasts, histiocytes, and multinucleated giant cells. The patient underwent debridement of the distal leg mass, metallosis, and wear debris surrounding the tibial component, followed by revision of the destructed polyethylene-bearing components. At the latest follow-up, 4 years after the revision surgery, the patient is alive and tumor-free, asymptomatic, and has no clinical or imaging evidence of wear and metallosis.

Arthroscopic debridement and irrigation of periprosthetic total elbow infection.

We report on a case of arthroscopic treatment of septic arthritis of the elbow joint in a 65-year-old man with an elbow endoprosthesis. Two months after arthroplasty of the elbow joint, the patient developed acute septic arthritis of the right elbow. Methicillin-sensitive Staphylococcus aureus was identified as the causative organism. Six days after the onset of symptoms, the patient was treated with a single arthroscopic procedure of the infected periprosthetic joint, including irrigation with 5 L of Ringer's lactate solution, debridement, and partial synovectomy with a 4.5-mm curved shaver. Intravenous antibiotic therapy was also used for 3 months including rifampicine and fucidic acid according to the intraoperative cultures. The acutely infected total elbow arthroplasty could be cured without removal of the endoprosthesis of the elbow. Ten months postoperatively, the patient remains free of symptoms and his blood rates are within normal limits.