Allergy in total knee replacement surgery: Is it a real problem?

Total knee arthroplasty is a common procedure, with extremely good clinical results. Despite this success, it produces 20% unsatisfactory results. Among the causes of these failures is metal hypersensitivity. Metal sensitization is higher in patients with a knee arthroplasty than in the general population and is even higher in patients undergoing revision surgery. However, a clear correlation between metal sensitization and symptomatic knee after surgery has not been ascertained. Surely, patients with a clear history of metal allergy must be carefully examined through dermatological and laboratory testing before surgery. There is no globally accepted diagnostic algorithm or laboratory test to diagnose metal hypersensitivity or metal reactions. The patch test is the most common test to determine metal hypersensitivity, though presenting some limitations. Several laboratory assays have been developed, with a higher sensitivity compared to patch testing, yet their clinical availability is not widespread, due to high costs and technical complexity. Symptoms of a reaction to metal implants present across a wide spectrum, ranging from pain and cutaneous dermatitis to aseptic loosening of the arthroplasty. However, although cutaneous and systemic hypersensitivity reactions to metals have arisen, thereby increasing concern after joint arthroplasties, allergies against implant materials remain quite rare and not a well-known problem. The aim of the following paper is to provide an overview on diagnosis and management of metal hypersensitivity in patients who undergo a total knee arthroplasty in order clarify its real importance

Safety and effectiveness of monochloramine treatment for disinfecting hospital water networks

The formation of potentially carcinogenic N-nitrosamines, associated with monochloramine, requires further research due to the growing interest in using this biocide for the secondary disinfection of water in public and private buildings. The aim of our study was to evaluate the possible formation of N-nitrosamines and other toxic disinfection by-products (DBPs) in hospital hot water networks treated with monochloramine. The effectiveness of this biocide in controlling Legionella spp. contamination was also verified. For this purpose, four different monochloramine-treated networks, in terms of the duration of treatment and method of biocide injection, were investigated. Untreated hot water, municipal cold water and, limited to N-nitrosamines analysis, hot water treated with chlorine dioxide were analyzed for comparison. Legionella spp. contamination was successfully controlled without any formation of N-nitrosamines. No nitrification or formation of the regulated DBPs, such as chlorites and trihalomethanes, occurred in monochloramine-treated water networks. However, a stable formulation of hypochlorite, its frequent replacement with a fresh product, and the routine monitoring of free ammonia are recommended to ensure a proper disinfection. Our study confirms that monochloramine may be proposed as an effective and safe strategy for the continuous disinfection of building plumbing systems, preventing vulnerable individuals from being exposed to legionellae and dangerous DBPs

The role of adipose derived stem cells in the treatment of rotator cuff tears: From basic science to clinical application

Over the last decade, regenerative medicine has become increasingly popular throughout the scientific community. The poor healing capacity at the tendon-bone interface makes the rotator cuff an appealing target for biologic agents. Adipose derived stem cells are mesenchymalcells with the capacity for self-renewal and mul-tipotential differentiation. They have been recently proposed, both in isolation and as adjuvants to existing surgical therapies, for the treatment of rotator cuff tears. Several studies have been carried out in this research field, starting from the biological characteristics of adipose derived stem cells, their preparation and culture, up to the application in the experimental field on animal models and on humans. The purpose of this study was to provide a state of the art about the current basic science and clinical literature for the effectiveness of adipose derived stem cells in the treatment of rotator cuff tears

Arthroscopic treatment of an unusual distal clavicle ostheochondroma causing rotator cuff impingement: Case report and literature review

Chronic shoulder impingement is one of the most common causes of shoulder pain. Intrinsic, extrinsic and secondary factors play a role in this syndrome; however the etiology of the pathology is still under debate. In rare cases, it can be caused by tumors, such as an osteochondroma. In the present study, a 49-year-old patient presented with shoulder pain for 6 months. Initially he underwent conservative treatment, without relief of symptoms. X-rays and MRI were then performed and showed the presence of an exostotic formation on the undersurface of the lateral third of the clavicle. The formation was arthroscopically removed. Histologic examination confirmed the diagnosis of osteochondroma. After surgery, the patient resumed fully activities with no symptoms within 3 months. At 1 year follow up, there are still no clinical or radiological signs of recurrence. This is, to our knowledge, the first case where an arthroscopic approach was used to remove an ostochondroma of the distal third of the clavicle

Anatomic reconstruction of the acromioclavicular joint provides the best functional outcomes in the treatment of chronic instability

Purpose: To systematically review the outcomes of surgical treatments of chronic acromioclavicular joint dislocation. Methods: Studies were identified by electronic databases (Ovid, PubMed). All studies reporting functional and radiological outcomes of surgical treatments of chronic acromioclavicular joint dislocations were included. Following data were extracted: authors and year, study design, level of evidence, number of patients, age, classification of acromioclavicular joint dislocation, time to surgery, surgical technique, follow-up, clinical and imaging outcomes, complications and failures. Descriptive statistics was used, when a data pooling was not possible. Comparable outcomes were pooled to generate summary outcomes reported as frequency-weighted values. Quality appraisal was assessed through the MINORS checklist. Results: Fourty-four studies were included for a total of 1020 shoulders. Mean age of participants was 38 years. Mean follow-up was 32.9 months. Arthroscopic techniques showed better results than open approach (p < 0.0001). Synthetic reconstructions demonstrated better functional outcomes compared to internal fixation and biologic techniques (p < 0.0001). Among biologic techniques, combined coracoclavicular and acromioclavicular ligaments reconstruction showed better Constant (p = 0.0270) and ASES (p = 0.0113) scores compared to isolated coracoclavicular ligaments reconstruction; anatomic biologic non-augmented graft reconstruction showed better Constant (p < 0.0001), VAS (p < 0.0001) and SSV (p = 0.0177) results compared to augmented techniques. No differences in functional outcomes could be found between anatomic biologic non-augmented graft versus synthetic reconstructions. Overall, methodological quality of the included studies was low. Conclusion: Anatomic reconstructions, both synthetic and biologic, showed the best functional results. Level of evidence: IV

Effects of (-)-linalool in the acute hyperalgesia induced by carrageenan, L-glutamate and prostaglandin E2

A series of studies performed in our laboratory have shown that (-)-linalool, the natural occurring enantiomer in essential oils, possesses anti-inflammatory and antinociceptive effects in different animal models. The antinociceptive effect of (-)-linalool has been ascribed to the stimulation of the cholinergic, opioidergic and dopaminergic systems, to its local anesthetic activity and to the blockade of N-methyl-D-aspartate (NMDA) receptors. In this study, we investigated the effect of systemic administration of (-)-linalool in the paw withdrawal test in rats, a model of thermal hyperalgesia induced by monolateral subplantar injection of carrageenan, L-glutamate or prostaglandin E(2). Carrageenan and L-glutamate induced a hyperalgesic effect on the injection side. In contrast, prostaglandin E(2) induced hyperalgesia in both the injection side and the contralateral side. Pretreatment with (-)-linalool (50-150 mg/kg) inhibited the development of acute hyperalgesia induced by carrageenan in the injected paw, with no effect on the contralateral paw. Furthermore, (-)-linalool at the highest dose used (200 mg/kg), reduced and reverted the decrease in paw withdrawal latencies induced by L-glutamate on the ipsilateral side, showing antihyperalgesic and antinociceptive effects. An antinociceptive effect was apparent also in the contralateral paw. Finally, (-)-linalool (200 mg/kg) increased paw withdrawal latency on the side contralateral to prostaglandin E(2) injection, but not on the side of the injection. The efficacy of (-)-linalool in decreasing the hyperalgesia induced by carrageenan, L-glutamate and prostaglandin E(2) suggests that this compound might be useful in pain conditions sustained by the development of neuronal sensitization