Massive Periprosthetic Osteolysis Spreads to the Soft Tissue and Pelvic Region after Primary Total Hip Replacement: A Case Report.

Introduction: Periprosthetic osteolysis (PPOL) is a serious complication after total hip replacement and requires immediate action to prevent further spread to nearby tissues and has the opportunity to restore hip function successfully. We present the case of PPOL of a patient with a challenging course of treatment. Case Report: We report a 75-year-old patient with PPOL that spreads to the soft tissues and pelvic region 14 years after primary total hip arthroplasty. At all stages of treatment, an elevated neutrophil-dominant cell count was detected in the analysis of synovial fluid aspiration of the left hip joint without detection of microbiological culture. Due to severe bone loss and general patient condition, no further surgical treatment was indicated, and there is no clear vision of future actions. Conclusion: Management of severe PPOL can be challenging, as there are limited surgical treatment options with a good long-term prognosis. If an osteolytic process is suspected, it should be treated as soon as possible to avoid more severe progression of the complications.

Vibration transmission in bone-anchored prosthesis under vertical load. Cadaver study.

BACKGROUND: Sensory feedback between a device and its user helps to improve the effectiveness of control and training processes. These improvements involve corrective actions and the accumulation of experience to accelerate patient training in device control. OBJECTIVES: Vibrations from rehabilitation devices are used as sensory feedback signals for improving rehabilitation outcomes. STUDY DESIGN: Variations in the bone-anchored prosthesis frequency responses and vibration transmissibility under compressive loading were studied. METHODS: Five laboratory samples consisting of the above-knee prosthesis, custom-made implant, and cadaver bone were first axially compressed using universal testing machine; preloaded construction vibrations were generated with a shaker to imitate external forces acting on these samples. The oscillations at the sample surface control points were tested with a laser vibrometer. For different values of axial loading, the frequency responses of the samples and indexes of vibration attenuation were obtained to examine the correlations between vibration transmissibility in the samples and axial loads. RESULTS: Increase in axial loading caused an increase in the resonance frequency and a simultaneous decrease in vibratory displacement within the sample. At low frequencies (40-80 Hz), increasing the axial load degraded transmissibility; at medium and high frequencies, transmissibility changes were unstable on increasing the axial load. CONCLUSIONS: The osseoperception phenomenon is because of perceived prosthesis vibration analysis by the user. Vibration transmissibility of a prosthesis sample depends on the axial compression and frequency of excitation. Decreasing the vibration amplitude while increasing axial load is the primary reason for reduced perception of vibration.

Proportion of the CD19-Positive and CD19-Negative Lymphocytes and Monocytes within the Peripheral Blood Mononuclear Cell Set is Characteristic for Rheumatoid Arthritis.

Background and objectives: Composition of the peripheral blood (PB) cell populations and their activation state reflect the immune status of a patient. Rheumatoid arthritis (RA) is characterized by abnormal B- and T-cell functions. The objective of this study was to assess the profiles of the PB mononuclear cell (PBMC) populations in patients with rheumatoid and osteoarthritis (OA) in comparison with healthy control (HC) subjects in order to evaluate the PBMC profiles as a potential diagnostic characteristic in RA. The second aim was to assess the CCR1 and CCR2 expression on PB lymphocytes and correlate it with the plasma levels of matrix metallopeptidase 9 (MMP-9), IL-17F, TNF-α, IL-6, and IL-10. Materials and Methods: The frequency and phenotype, including CCR1 and CCR2, of the PBMC populations (monocytes, CD19+B cells, and T/NK lymphocytes) in RA (n = 15) and OA (n = 10) patients and HC (n = 12) were analyzed by five-color flow cytometry. DNA of the viruses, HHV-6, HHV-7, and B19, in the whole blood and cell-free plasma, were assessed by nested-polymerase chain reaction (PCR). Results: Active persistent or acute infections, caused by HHV-6, HHV-7, or B19, were not detected in patients of this study. Both CCR1 and CCR2 were determined on the PB B and T/NK lymphocytes in several RA and OA patients and HCs. However, in patients, the frequency of the CCR1-positive T/NK lymphocytes showed a weak negative correlation with the IL-10 level, while the frequency of the CCR2-positive B cells correlated positively with the level of IL-6. Statistically significant differences in the proportions of the CD19-positive and CD19-negative lymphocyte and monocyte subsets within the PBMC set were determined between RA and OA patients and HC adults. Conclusions: We have shown in our pilot study with rather small cohorts of patients that the PBMC-population profiles were very consistent, and statistically significantly differed between RA and OA patients and HC subjects.

Resection Arthroplasty Treatment Possibility for a Patient with Fibrous Dysplasia, Chronic Osteomyelitis, and Recurrent Periprosthetic Hip Joint Infection: A Case Report.

INTRODUCTION: Fibrous dysplasia (FD) is a rare congenital abnormality, in which parts of bone are replaced with fibrous stroma and woven bone, making it susceptible to pathological fractures. Osteomyelitis following intramedullary nailing of such fractures of the femur and periprosthetic joint infection (PJI) after hip arthroplasty is one of the most devastating complications and a true challenge for the orthopedic surgeon. To the best of our knowledge, this is the 1st time, such complications are reported in a patient with monostotic FD. CASE REPORT: We present a 30-year-old male patient with FD of the left femur, chronic osteomyelitis, recurrent periprosthetic hip joint infection after multiple revision arthroplasties, and two episodes of axillary vein thrombosis. Due to the severe structural changes and a large medial wall defect in the proximal femur with impairment of a large soft tissue zone, it was decided during operation not to put any other implants in the hip joint and perform only a resection hip arthroplasty procedure. CONCLUSION: Managing a recurrent PJI in a patient with poor bone quality, severe bone defects, soft tissue compromise, and thromboembolic events is challenging even for the most experienced orthopedic surgeon. Resection arthroplasty is a salvage treatment option that should be considered in such complex cases.

Ten to fifteen-year clinical and radiographic follow-up with a third-generation cementless stem in a young patient population.

PURPOSE: Outcome data beyond 11 years of follow-up is not available for the third-generation Zweymüller femoral stem in combination with a polyethylene bearing. We report ten to 15-year results with this total hip arthroplasty (THA) combination in a young population. METHODS: A retrospective, observational, non-randomised, single-centre, clinical observational study was conducted in which 311 primary THAs were performed in 276 patients between 1996 and 2000 using a third-generation Zweymüller stem. The mean age of the patients at operation was 47.4 years (range 18-77 years). RESULTS: Stem survival for any reason was 93.5% after ten years and 89.6% after 13 years, and the probability of aseptic stem loosening was 98.7% at both ten and 13 years. The occurrence of femoral radiolucent lines was low, at just 17.2%. Minor femoral osteolysis was identified in 30% of patients and was attributed to polyethylene liner wear. Clinical and patient satisfaction outcomes were in line with previous investigations, and the rate of adverse events was low. CONCLUSIONS: The third-generation Zweymüller stem shows good radiographic and clinical results and good longevity, including in the younger osteoarthritic patient. The use of low-wear bearings may further reduce the rate of osteolysis and wear-related revision in young and active patients.