The outcomes of acute periprosthetic joint infection following unicompartmental knee replacement managed with early debridement, Antibiotics, and implant retention.

BACKGROUND: Periprosthetic joint infection (PJI) following unicompartmental knee replacement (UKR) is an uncommon, yet serious, complication. There is a paucity of evidence regarding the effectiveness of Debridement-Antibiotics-and-Implant-Retention (DAIR) in this setting. The aim of this study is to investigate the effectiveness of DAIR for acute UKR PJI. METHOD: Between 2006 and 2019, 5195 UKR were performed at our institution. Over this period, sixteen patients underwent DAIR for early, acute PJI. All patients met MSIS PJI diagnostic criteria. The median age at DAIR was 67 years (range 40-73) and 12 patients were male (75.0%). The median time to DAIR was 24 days (range 6-60). Patients were followed up for a median of 6.5 years (range1.4-10.5) following DAIR. RESULTS: 0.3% (16/5195) of UKR in our institution had a DAIR within 3 months. 15 of 16 patients (93.8%) were culture positive, with the most common organism MSSA (n = 8, 50.0%). Patients were treated with an organism-specific intravenous antibiotic regime for a median of 6 weeks, followed by oral antibiotics for a median duration of 6 months. The Kaplan-Meier survivor estimate for revision for PJI was 57% (95%CI: 28-78%) at five years, and survivor estimate for all cause revision 52% (95%CI: 25-74%).The median Oxford Knee Score for patients with a viable implant at final follow-up was 45 points (range 39-46). CONCLUSION: Early, acute PJI after UKR is rare. DAIR had a moderate success rate, with infection-free survivorship of 57% at 5 years. Those successfully treated with DAIR had excellent functional outcome and implant survival.

In-plasma analysis of plasma-surface interactions.

During deposition, modification, and etching of thin films and nanomaterials in reactive plasmas, many active species can interact with the sample simultaneously. This includes reactive neutrals formed by fragmentation of the feed gas, positive ions, and electrons generated by electron-impact ionization of the feed gas and fragments, excited states (in particular, long-lived metastable species), and photons produced by spontaneous de-excitation of excited atoms and molecules. Notably, some of these species can be transiently present during the different phases of plasma processing, such as etching of thin layer deposition. To monitor plasma-surface interactions during materials processing, a new system combining beams of neutral atoms, positive ions, UV photons, and a magnetron plasma source has been developed. This system is equipped with a unique ensemble of in-plasma surface characterization tools, including (1) a Rutherford Backscattering Spectrometer (RBS), (2) an Elastic Recoil Detector (ERD), and (3) a Raman spectroscopy system. RBS and ERD analyses are carried out using a differentially pumped 1.7 MV ion beam line Tandetron accelerator generating a beam at grazing incidence. The ERD system is equipped with an absorber and is specifically used to detect H initially bonded to the surface; higher resolution of surface H is also available through nuclear reaction analysis. In parallel, an optical port facing the substrate is used to perform Raman spectroscopy analysis of the samples during plasma processing. This system enables fast monitoring of a few Raman peaks over nine points scattered on a 1.6 × 1.6 mm2 surface without interference from the inherent light emitted by the plasma. Coupled to the various plasma and beam sources, the unique set of in-plasma surface characterization tools detailed in this study can provide unique time-resolved information on the modification induced by plasma. By using the ion beam analysis capability, the atomic concentrations of various elements in the near-surface (e.g., stoichiometry and impurity content) can be monitored in real-time during plasma deposition or etching. On the other hand, the evolution of Raman peaks as a function of plasma processing time can contribute to a better understanding of the role of low-energy ions in defect generation in irradiation-sensitive materials, such as monolayer graphene.

Severe tardy ulnar nerve palsy caused by traumatic cubitus valgus deformity: functional outcome of subcutaneous anterior transposition.

Ten male patients with McGowan's grade III ulnar neuropathy due to traumatic cubitus valgus deformity underwent anterior subcutaneous ulnar transposition. Evaluation was performed using subjective and objective measures, and a modified Bishop score. After operation, subjective sensory and motor disturbances were improved or resolved in most of the patients, while objective measures improved less well. Improvement in two-point discrimination (2PD) was consistently associated with symptom relief. All of the patients reported satisfaction with the operation. There were no complications or recurrences. The results of ulnar nerve transposition in our patients were comparable to the results of this operation in patients with severe idiopathic cubital tunnel syndrome. Although the outcome of surgery is not always satisfactory in severe ulnar neuropathy, symptom relief may justify performing the operation.

(32)P colloid radiosynovectomy in treatment of chronic haemophilic synovitis: Iran experience.

Repeated intra-articular bleeding with subsequent development of chronic synovitis and cartilage changes, leading to haemophilic arthropathy, is one the most debilitating problems in haemophilic patients. Radiosynovectomy is a familiar therapeutic choice in management of chronic synovitis in haemophilia. We report the treatments results of synoviorthesis with (32)P chromic phosphate with emphasis on clinical aspects. Between 2002 and 2006 we performed 66 procedures in 53 patients. Seven patients were excluded. The remaining 46 patients were followed for an average of 31 months. The mean age of patients at the time of injection was 15.9 years (range: 6-28). There were three repeat injections. According to Fernandez-pallazi and Cavilgia clinical classification (Table 1) [23], nine joints were Stage II and 46 were Stage III. In latest follow-up, 77% of patients reported at least a 50% decrease in bleeding frequency after treatment (P < 0.0001). The need for antihaemophilic factor consumption dropped by about 74% postradiosynovectomy (P < 0.0001). In most of the injected joints, the range of motion remained stable or improved. A trend was found for the number of haemarthrosis to increase after a period of considerable improvement. Synoviorthesis using (32)P effectively reduces the intra-articular bleeding rate and factor concentrate use. Durability of the response seems to be unpredictable, perhaps attributable to the late intervention. An early radiosynovectomy might be more helpful in terms of stability of response to treatment.

Operative treatment of anterior heterotopic bone formation of the elbow in a patient with severe haemophilia A.

There is no statistical data on the incidence of heterotopic ossification among patients with haemophilia, and a few reports documenting this entity in haemophilia are available. Although post-traumatic heterotopic ossification about the elbow is a well-recognized complication, we are not aware of any previously reported case in haemophiliacs. An 8-year-old boy with severe haemophilia A presented with fixed elbow in 80 degrees of flexion. Radiographs disclosed a mature anterior heterotopic ossification in the form of complete ulnohumeral bony bridge. Surgical excision of the heterotopic bone was performed. A full elbow range of motion was obtained after long-term physiotherapy. We conclude that this surgery is safe and successful in haemophilic patients, if performed at the right time under optimal situation.