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Introduction:The present study compares the outcome of the long cemented stem and the revision uncemented stem used in periprosthetic femoral fractures. We propose that the revision with a long stem cemented prosthesis does not compromise fracture healing. Patients and Methods: A consecutive series of 37 patients, operated between 2010 and 2017, were enrolled in a retrospective analysis. A long cemented stem was implanted in 21 patients (study group; age at operation: 63 to 89 years). A distally tapered fluted uncemented stem was used in 16 patients (control group; age at operation: 35 to 77 years). The clinical outcome was evaluated with Merle d'Aubigné and Postel scoring system. Standard radiographs were taken before surgery, at 3, 6, and 12 months postoperatively, and last follow-up. Any and all complications during the follow-up period were recorded. Results: Although a significant difference (P = 0.006) was observed in the post-operative Merle d´Aubigné score over the 12-month follow-up period, no significant difference (P = 0.066) was found in the post-operative pain score between the study and control groups. Periodic radiographic assessments showed the disappearance of radiolucent lines and the diaphyseal part of the fracture was healed in all 34 followed-up cases during the first annual follow-up. Early surgical complications were seen in both groups, the medical complications were observed only in the study group. Conclusion: Based on our results, periprosthetic fractures of the femur after a total hip arthroplasty were associated with significant morbidity and increased mortality in elderly patients. Revision with a long-stem cemented prosthesis provided early pain-free weightbearing without compromising the healing of femoral fractures in elderly patients with osteoporotic bone, altered mobility, poor balance, and reduced cognitive capacity.

Although progress is evident in the effective treatment of joint replacement-related infections, it still remains a serious issue in orthopedics. As an example, the local application of antibiotics-impregnated bone grafts supplies the high drug levels without systemic side effects. However, antibiotics in the powder or solution form could be a risk for local toxicity and do not allow sustained drug release. The present study evaluated the use of an antibiotic gel, a water-in-oil emulsion, and a PLGA microparticulate solid dispersion as depot delivery systems impregnating bone grafts for the treatment of joint replacement-related infections. The results of rheological and bioadhesive tests revealed the suitability of these formulations for the impregnation of bone grafts. Moreover, no negative effect on proliferation and viability of bone marrow mesenchymal stem cells was detected. An ex vivo dissolution test of vancomycin hydrochloride and gentamicin sulphate from the impregnated bone grafts showed a reduced burst and prolonged drug release. The PLGA-based formulation proved to be particularly promising, as one-day burst release drugs was only 15% followed with sustained antibiotics release with zero-order kinetics. The results of this study will be the basis for the development of a new product in the Tissue Section of the University Hospital for the treatment of bone defects and infections of joint replacements.

Mycobacterium chelonae, a rapidly growing nontuberculous mycobacterium, is usually described as a causative agent of soft tissue infections (postsurgical, posttraumatic, posttransplantation, postinjection, catheter infection, etc.), but only rarely as a cause of osteomyelitis. The authors describe a case report of a 72-year-old man with osteomyelitis of the talus. Initially, the infection was assessed as a soft tissue infection, without any osteolytic changes on the X-ray. After cultivation with subsequent targeted molecular typing of the rpoB gene, M. chelonae was identified from the affected tissue. The bone involvement was subsequently detected on MRI and confirmed histologically with findings of the granulomatous tissue and acid-fast bacilli. The patient was initially treated intravenously with a combination of tigecycline, amikacin, and moxifloxacin for 4 weeks, after which the oral combination of doxycycline and moxifloxacin continued. Identification of the infecting pathogen using molecular typing thus helped to establish the correct diagnosis and represents a rarely described case of osteomyelitis caused by M. chelonae.