Dithiotreitol pre-treatment of synovial fluid samples improves microbiological counts in peri-prosthetic joint infection.

PURPOSE: Synovial fluid cultures of periprosthetic joint infections (PJI) may be limited by bacteria living in the fluids as biofilm-aggregates. The antibiofilm pre-treatment of synovial fluids with dithiotreitol (DTT) could improve bacterial counts and microbiological early stage diagnosis in patients with suspected PJI. METHODS: Synovial fluids collected from 57 subjects, affected by painful total hip or knee replacement, were divided into two aliquots, one pre-treated with DTT and one with normal saline. All samples were plated for microbial counts. Sensitivity of cultural examination and bacterial counts of pre-treated and control samples were then calculated and statistically compared. RESULTS: Dithiothreitol pre-treatment led to a higher number of positive samples, compared to controls (27 vs 19), leading to a statistically significant increase in the sensitivity of the microbiological count examination from 54.3 to 77.1% and in colony-forming units count from 1884 ± 2.129 CFU/mL with saline pre-treatment to 20.442 ± 19.270 with DTT pre-treatment (P = 0.02). CONCLUSIONS: To our knowledge, this is the first report showing the ability of a chemical antibiofilm pre-treatment to increase the sensitivity of microbiological examination in the synovial fluid of patients with peri-prosthetic joint infection. If confirmed by larger studies, this finding may have a significant impact on routine microbiological procedures applied to synovial fluids and brings further support to the key role of bacteria living in biofilm-formed aggregates in joint infections.

Is debridement really the best we can do for periprosthetic joint infections following total ankle replacements? A systematic review and meta-analysis.

BACKGROUND: Ankle periprosthetic joint infections are rising in number, but an evidence-based gold standard treatment has not been defined yet. METHODS: We made a systematic review about the operative treatment of infections following total ankle arthroplasty. Proportional meta-analysis was used to summarize effects of the surgical techniques included. Primary outcome of this study was infection eradication, followed by complications, re-interventions, amputation rates and functions. RESULTS: We included six studies(113 patients) reporting 6 types of surgical interventions, mostly irrigation and debridement (35.4%) and two-stage revisions (24.8%). No differences among all analyzed techniques were found in the infection eradication outcome as well as in the secondary outcomes. Patients receiving a permanent spacer are most likely to end up with amputation. CONCLUSIONS: Literature dealing with infections after total ankle replacement is currently composed by few low-quality articles. The overlapping of confidence intervals related to all analyzed interventions showed no superiority of either technique. LEVEL OF EVIDENCE: III.

Two-stage cementless hip revision for peri-prosthetic infection with an antibacterial hydrogel coating: results of a comparative series.

PURPOSE: The aim of this study was to investigate the hypothesis that a two-stage exchange procedure, performed with an antibiotic-loaded, fast-resorbable hydrogel coating, may provide better infection cure rate than a two-stage procedure without the coating, in patients affected by peri-prosthetic hip infection. METHODS: In this case-control study, 27 patients, treated with a two-stage procedure, using cementless implants coated with an antibiotic-loaded hydrogel (DAC®, "Defensive Antibacterial Coating"), were compared with 27 matched controls, treated with a two-stage cementless revision procedure, without the coating. RESULTS: At a mean follow-up of 2.7 (minimum 2.1-maximum 3.5) years, no evidence of infection, implant loosening, or adverse events were observed in the DAC-treated group, compared to four cases of infection recurrence in the control group. CONCLUSIONS: Although in a relatively limited series of patients our data show that cementless two-stage hip revision, performed with an antibacterial hydrogel coating, may provide better infection control than two-stage without the coating, with reduced hospitalization time, these findings warrant further studies in the possible applications of antibacterial coating technologies to treat implant-related infections.

ICS classification system of infected osteosynthesis: Long-term results.

The best treatment strategy for infected osteosyntheses is still debated. While hardware removal or eventually early device exchange may be necessary in most of the cases, temporary hardware retention until fracture healing can be a valid alternative option in others. Aim of the present study is to report the long-term results of 215 patients with infected osteosyntheses, treated according to the ICS (Infection, Callus, Stability) classification in two Italian hospitals. Patients classified as ICS Type 1 (N = 83) feature callus progression and hardware stability, in spite of the presence of infection; these patients were treated with suppressive antibiotic therapy coupled with local debridement in 18.1% of the cases, and no hardware removal until bone healing. Type 2 patients (N = 75) are characterized by the presence of infection and hardware stability, but no callus progression; these patients were treated as Type 1 patients, but with additional callus stimulation therapies. Type 3 patients (N = 57), showing infection, no callus progression and loss of hardware stability, underwent removal and exchange of the fixation device. Considering only the initial treatment, performed according to the ICS classification, at a minimum 5 years follow up, 89.3% achieved bone healing and 93.5% did not show infection recurrence. The ICS classification appears as a useful and reliable tool to help standardizing the decision-making process in treating infected osteosynthesis with the most conservative approach.

Managing large bone defects in children: a systematic review of the 'induced membrane technique'.

Thirty years after its description by Masquelet in 1986, this is the first systematic review aiming to critically evaluate the 'induced membrane technique' effectiveness in achieving bone union in children. Only six papers fulfilled our inclusion criteria (54 patients). The relatively small number of reported cases did not allow a formal meta-analysis. The tibia was the most involved bone. Most frequent aetiologies were congenital pseudoarthrosis and tumour resections. Although effective in achieving bone healing in ∼91% of the patients (bone defects ≤24 cm long), the induced membrane technique was associated with a high rate of complications (54% of patients). LEVEL OF EVIDENCE: IV.

The Concept of Biofilm-Related Implant Malfunction and "Low-Grade Infection".

Biofilms have a tremendous impact on industrial machines working in moist environments, while in biological systems their effect is further complicated by the host's response.Implant-related infections are a complex process, starting with bacterial adhesion and biofilm formation, followed by the variable interaction between host, implant, microorganisms and their by-products. Depending on the balance of these factors, different clinical presentations are observed, which may eventually, at times, shift from one into the other.-"Implant malfunction" displays only mild clinical signs/symptoms - light pain and/or slight soft tissue contracture or functional impairment - with negative infection/inflammatory markers; it requires prolonged cultures, antibiofilm and eventually genomic investigations for pathogen detection;-"Low-grade infection" features recurrent or persistent pain and/or soft tissue contracture with various functional impairment and mixed positive/negative markers of infection/inflammation; pathogen identification requires prolonged cultures and antibiofilm techniques;-"High-grade infection" displays classical signs/symptoms of infection/inflammation with positive tests; pathogen identification is often possible with traditional microbiological techniques, but is better achieved with prolonged cultures and antibiofilm processing.Understanding biofilms-related clinical presentations is crucial for physicians, to implement the best diagnostic and therapeutic measures, and for regulatory bodies, to define the evaluation process of technologies aimed at reducing implants' malfunctions and infections, like anti-adhesive and antibiofilm coatings, that should be regulated as (part of) medical devices, requiring a suitable post-marketing surveillance.Only an effective antibiofilm-targeted approach from all players will hopefully allow the medical community to mitigate the current unacceptable social and economical burden of implant-related infections and malfunctions.

Antibacterial coating of implants in orthopaedics and trauma: a classification proposal in an evolving panorama.

Implanted biomaterials play a key role in current success of orthopedic and trauma surgery. However, implant-related infections remain among the leading reasons for failure with high economical and social associated costs. According to the current knowledge, probably the most critical pathogenic event in the development of implant-related infection is biofilm formation, which starts immediately after bacterial adhesion on an implant and effectively protects the microorganisms from the immune system and systemic antibiotics. A rationale, modern prevention of biomaterial-associated infections should then specifically focus on inhibition of both bacterial adhesion and biofilm formation. Nonetheless, currently available prophylactic measures, although partially effective in reducing surgical site infections, are not based on the pathogenesis of biofilm-related infections and unacceptable high rates of septic complications, especially in high-risk patients and procedures, are still reported.In the last decade, several studies have investigated the ability of implant surface modifications to minimize bacterial adhesion, inhibit biofilm formation, and provide effective bacterial killing to protect implanted biomaterials, even if there still is a great discrepancy between proposed and clinically implemented strategies and a lack of a common language to evaluate them.To move a step forward towards a more systematic approach in this promising but complicated field, here we provide a detailed overview and an original classification of the various technologies under study or already in the market. We may distinguish the following: 1. Passive surface finishing/modification (PSM): passive coatings that do not release bactericidal agents to the surrounding tissues, but are aimed at preventing or reducing bacterial adhesion through surface chemistry and/or structure modifications; 2. Active surface finishing/modification (ASM): active coatings that feature pharmacologically active pre-incorporated bactericidal agents; and 3. Local carriers or coatings (LCC): local antibacterial carriers or coatings, biodegradable or not, applied at the time of the surgical procedure, immediately prior or at the same time of the implant and around it. Classifying different technologies may be useful in order to better compare different solutions, to improve the design of validation tests and, hopefully, to improve and speed up the regulatory process in this rapidly evolving field.

Does a thrombin-based topical haemostatic agent reduce blood loss and transfusion requirements after total knee revision surgery? A randomized, controlled trial.

PURPOSE: The aim of the present study was to assess the efficacy of a thrombin-based topical haemostatic in reducing blood requirements after total knee replacement (TKR) revision surgery. METHODS: This prospective, randomized, controlled study was designed to evaluate the haemostatic efficacy and safety of a thrombin-based topical haemostatic (Floseal) versus standard treatment in patients receiving total knee revision arthroplasty. The decrease in haemoglobin values postsurgery and the blood units transfused were recorded. The decision to transfuse was made by a surgeon blinded to the patient's group allocation. RESULTS: Forty-eight patients were enroled in the study; twenty-four patients each were randomized to the treatment and control groups, respectively. The median decrease in haemoglobin concentration on the first postoperative day was 2.2 g/dL in the treatment group and 2.7 g/dL in the control group. A significant reduction in units of blood transfused was also observed in the treatment group compared with the control group [1.1 ± 1.13 (range 0-4) vs. 1.9 ± 1.41 (range 0-5) blood units; P = 0.04]. No major treatment-related adverse events were recorded in the study. CONCLUSIONS: This study shows that a thrombin-based topical haemostatic reduces the need for blood transfusion in TKR revision surgery. CLINICAL RELEVANCE: A thrombin-based topical haemostatic agent can be an appropriate solution to enhance haemostasis and vessel sealing at the operative site in TKR revision surgery, in order to reduce the need for blood transfusion after surgery. LEVEL OF EVIDENCE: II.

Role for irrigation and debridement in periprosthetic infections.

Irrigation and debridement (I&D) has been described as a possible option to eradicate early postoperative periprosthetic hip and knee infections, as well as late, acute, and hematogenous ones. Still, the literature fails to uniquely assess the effectiveness of this procedure and often provides conflicting evidence. To reconcile this difference, a systematic review of the available literature from 1970 to 2013 was undertaken. Fifteen articles, for a total of 796 patients, met the inclusion criteria; the average success rate was 44.9 and 52% after a single or repeated I&D procedures, respectively, at an average of 4 years follow-up. Despite the methodological differences and the heterogeneity of the material reviewed, this study demonstrates that this procedure only attains a relatively low success rate of infection eradication, depending on when patients are selected for surgical intervention according to the timeframe of their symptoms.

Cementless modular intramedullary nail without bone-on-bone fusion as a salvage procedure in chronically infected total knee prosthesis: long-term results.

PURPOSE: Our purpose was to evaluate long-term results of two-stage cementless intramedullary nailing without achieving bone-to-bone fusion for treating chronically infected total knee arthroplasty (TKA). METHODS: Thirty-eight patients treated according to the same protocol were retrospectively evaluated for clinical, functional, laboratory and radiological outcomes. RESULTS: Spacer exchange was necessary for infection persistence in one case. At a minimum two year follow-up, 34 patients (89.5%) showed no infection recurrence; among these 34 patients, 29 (85.3%) reported no or moderate pain [visual analogue scale (VAS) ≤3]; mild to moderate handicap (Lequesne Algofunctional Index < 7.5) was observed in 18 patients (52.9%). No patient underwent revision for aseptic loosening, and no nail breakage was observed. CONCLUSIONS: Two-stage cementless intramedullary nailing without achieving bone-to-bone fusion is a viable option for treating chronically infected TKA in selected, complex cases.

Bioactive glass BAG-S53P4 for the adjunctive treatment of chronic osteomyelitis of the long bones: an in vitro and prospective clinical study.

BACKGROUND: This study aimed to explore the in vitro antibacterial activity of the bioglass BAG S53P4 against multi-resistant microorganisms commonly involved in osteomyelitis and to evaluate its use in surgical adjunctive treatment of osteomyelitis. METHODS: In vitro antibacterial activity of BAG-S53P4 against methicillin resistant Staphylococcus aureus and Staphylococcus epidermidis, Pseudomonas aeruginosa and Acinetobacter baumannii isolates was evaluated by means of time kill curves, with colony counts performed after 24, 48 and 72 hours of incubation. In vivo evaluation was performed by prospectively studying a cohort of 27 patients with a clinically and radiologically diagnosed osteomyelitis of the long bones in an observational study. Endpoints were the absence of infection recurrence/persistence at follow-up, no need for further surgery whenever during follow-up and absence of local or systemic side effects connected with the BAG use. RESULTS: In vitro tests regarding the antibacterial activity of BAG S53P4 showed a marked bactericidal activity after 24 hrs against all the tested species. This activity continued in the subsequent 24 hrs and no growth was observed for all strains after 72 hrs. Results of the clinical study evidenced no signs of infection in 24 patients (88.9%) at the follow-up, while 2 subjects showed infection recurrence at 6 months from index operation and one more needed further surgical procedures. BAG-S53P4 was generally well tolerated. CONCLUSIONS: The in vitro and in vivo findings reinforce previous observations on the efficacy of BAG-S53P4 for the treatment of chronic osteomyelitis of the long bones, also in the presence of multi-resistant strains and in immunocompromised hosts, without relevant side effects and without the need for locally adding antibiotics. TRIAL REGISTRATION: Deutschen Register Klinischer Studien (DRKS) unique identifier: DRKS00005332.

Use of dithiothreitol to improve the diagnosis of prosthetic joint infections.

Diagnosis of prosthetic joint infections (PJIs) remains a challenge for microbiologists, despite new techniques for bacteria isolation have been developed in recent years. A widely recognized standard method has not yet been indicated mainly because of limitations due difficult procedures and need of dedicated instrumentation. We evaluated the ability of a sulfhydryl compound routinely used in microbiology laboratories, dithiothreitol (DTT), to dislodge bacteria from biofilm, keeping them alive and cultivable for identification and antibiotic susceptibility testing. We compared DTT treatment against sonication of prosthesis and culture of periprosthetic tissues, in order to establish if it could be introduced in routine microbiological diagnosis of PJIs. The study was conducted on 76 patients, 34 with aseptic loosening of their prosthesis and 42 who were diagnosed for PJI. DTT treatment gave results similar to sonication in terms of bacterial yielding. Sonication provided higher sensitivity (71.4%) and specificity (94.1%) respect to periprosthetic tissue culture, while DTT showed the same specificity of sonication but a better sensitivity (85.7%), especially when the causative microorganism was Staphylococcus epidermidis. In conclusion, we demonstrated that DTT could be used for PJIs diagnosis, thanks to its ease of use and its high sensitivity and specificity.

Antibiofilm agents and implant-related infections in orthopaedics: where are we?

Orthopaedics is currently the largest market of biomaterials worldwide and implant-related infections, although relatively rare, remain among the first reasons for joint arthroplasty and osteosynthesis failure. Bacteria start implant infection by adhering to biomaterials and producing biofilms, which represent a major reason for bacterial persistence, in spite of antibiotic treatment and host's defence. In the last two decades, a number of different antibiofilm agents have been studied and both in vitro and in vivo results appear now promising, even if their effective role in orthopaedics remains to be assessed. In this review, we introduce an original classification of antibiofilm agents, based on their mechanism of action and examine the available data concerning their possible application to orthopaedic implant-related infections. Molecules that interfere with biofilm production (biofilm prevention agents) include anti-adhesion compounds, quorum sensing inhibitors, non-steroideal anti-inflammatory drugs, and antimicrobial peptides; N-acetylcysteine and specific enzymes promise the greatest therapeutic possibilities by disrupting established biofilms (biofilm disrupting agents). The identification of antimicrobials able to bypass the biofilm barrier (biofilm bypassing agents), and antibiofilm vaccines are further strategies aimed to reduce the impact of biofilm-related infections, opening new pathways in controlling implant-related infections. However, this review shows that still insufficient knowledge is currently available as to regard the efficacy and safety of the investigated antibiofilm strategies to treat infection that involve bone tissue and biomaterials commonly implanted in orthopaedics, pointing out the need for further research in this promising field.

Value of digital telethermography for the diagnosis of septic knee prosthesis: a prospective cohort study.

BACKGROUND: Diagnosis of peri-prosthetic infection remains challenging, often requiring a combination of different tests. METHODS: In this prospective, case-control study, the diagnostic accuracy of telethermography was evaluated in a group of seventy patients who had had a total knee replacement and were undergoing a reoperation because of infection or another implant-related problem, after a minimum of one year from implant. RESULTS: An average differential temperature of the affected versus not affected knee of 1.9 °C was observed in infected prosthesis, compared to 0.3 °C in aseptic failures. Considering a normal reference value equal or less than 1.0 °C, telethermography showed an accuracy, sensitivity, specificity, positive and negative predictive value of, respectively: 0.90, 0.89, 0.91, 0.91, 0.88. CONCLUSIONS: Digital telethermography is a reliable option for diagnosing peri-prosthetic knee infection.

Preformed antibiotic-loaded cement spacers for two-stage revision of infected total hip arthroplasty. Long-term results.

Two-stage revision is the most widely accepted and performed intervention for chronically infected hip prosthesis and different interim spacers have been proposed. In recent years, antibiotic-loaded preformed spacers have become available on the market. The aim of this retrospective study was to assess the long-term results of two-stage revision with preformed spacers and uncemented hip prosthesis for the treatment of septic hip prosthesis. From 2000 to 2010, 183 consecutive patients underwent two-stage revision of septic hip prosthesis, with a same protocol, including preformed antibiotic-loaded cement spacer and a cementless modular hip revision prosthesis and four to six weeks antibiotic administration. Clinical and radiologic assessment at a minimum follow-up of two years was performed. At a minimum two years follow-up, 10 patients (5.4%) had had an infection recurrence, four (2.2%) an aseptic loosening and four more required partial revision of the modular components of the prosthesis, because of hip instability/dislocation; 21 patients died or were lost to follow-up. Considering all the reasons for revision, survivorship at eleven years was 93.9%. Harris Hip Score improved from 29.1 ± 14.6 pre-operatively to 41.1 ± 15.9 after spacer implant and 81.7 ± 17.6 after hip revision. The main complications after spacer implant included: spacer dislocation (16.4%), intra-operative femoral fractures (2.7%), and thromboembolism (2.1%). Complications after hip revision were: instability/dislocation (4,3%), intra-operative femoral fractures (1.6%), and thromboembolism (3.3%). Two-stage revision of septic hip prosthesis with preformed antibiotic-loaded spacers and cementless hip prosthesis provides satisfactory long-term results, with reduced complications.

Value of debridement and irrigation for the treatment of peri-prosthetic infections. A systematic review.

Debridement and irrigation has been proposed as a salvage procedure for early post-operative and late acute haematogenous periprosthetic hip and knee infections, however the effective ability of this procedure to avoid recurrent infection is still debated. In this systematic review of the literature we reviewed full-text papers published from 1970 through 2011, that reported the success rate of infection eradication after debridement and irrigation with prosthesis retention for the treatment of early septic complications (within six weeks from surgery) or late acute haematogenous infections after hip or knee prosthesis. In all, 14 original articles, reporting the results of 710 patients were retrieved. The average success rate has been, respectively, 45.9% and 52% after a single or repeated debridement and irrigation procedures, at a mean follow-up of 53.3 months. The methodological limitations of this study and the heterogeneous material in the reviewed papers notwithstanding, this systematic review shows that debridement and irrigation procedure is associated with a rather poor outcome, even in a population of patients selected on the basis of symptoms' duration and patients should be adequately informed prior to undergo this salvage procedure.

Antineuropathic and antinociceptive drugs combination in patients with chronic low back pain: a systematic review.

Purpose. Chronic low back pain (LBP) is often characterized by both nociceptive and neuropathic components. While various monotherapies have been reported of only limited efficacy, combining drugs with different mechanisms of action and targets appears a rational approach. Aim of this systematic review is to assess the efficacy and safety of different combined pharmacological treatments, compared to monotherapy or placebo, for the pharmacological treatment of chronic LBP. Methods. Published papers, written or abstracted in English from 1990 through 2011, comparing combined pharmacological treatments of chronic LBP to monotherapy or placebo were reviewed. Results. Six articles met the inclusion criteria. Pregabalin combined with celecoxib or opioids was shown to be more effective than either monotherapy. Oxycodone-paracetamol versus previous treatments and tramadol-paracetamol versus placebo were also reported as effective, while morphine-nortriptyline did not show any benefit over any single agent. Conclusions. In spite of theoretical advantages of combined pharmacological treatments of chronic LBP, clinical studies are remarkably few. Available data show that combined therapy, including antinociceptive and antineuropathic agents is more effective than monotherapy, with similar side effects.

Successful staged hip replacement in septic hip osteoarthritis in osteopetrosis: a case report.

BACKGROUND: Osteopetrosis is a rare, inherited, bone disorder, characterized by osteosclerosis, obliteration of the medullary cavity and calcified cartilage. The autosomal dominant form is compatible with a normal life span, although fractures often result from minimal trauma, due to the pathologic nature of bone. Osteomyelitis is common in patients with osteopetrosis because of a reduced resistance to infection, attributed to the lack of marrow vascularity and impairment of white cell function. Only one case of osteomyelitis of the proximal third of the femur has been previously reported, treated with several repeated debridements and finally with femoral head resection. Here we present for the first time a case of a staged implant of a cementless total hip prosthesis for the treatment of a septic hip in femoral neck nonunion in osteopetrosis. CASE PRESENTATION: A 36-years-old woman, affected by autosomal dominant osteopetrosis was referred to our department because of a septic hip arthritis associated with femoral neck septic non-union, with draining fistulas. The infection occurred early after a plate osteosynthesis for a closed perthrocanteric fracture of the femur and persisted in spite of osteosynthesis removal, surgical debridement and external fixation. In our hospital the patient underwent accurate debridement, femoral head and greater trochanter resection, preparation of the diaphyseal intramedullary canal and implant of an antibiotic-loaded cement spacer. The spacer was exchanged after one month, due to infection recurrence and four months later, a cementless total hip arthroplasty was implanted, with no clinical and laboratory signs of infection recurrence at two years follow-up. CONCLUSIONS: In case of hip septic arthritis and proximal femur septic non-union, femoral head resection may not be the only option available and staged total hip arthroplasty can be considered.

Bone and joint infections in adults: a comprehensive classification proposal.

INTRODUCTION AND METHODS: Ten currently available classifications were tested for their ability to describe a continuous cohort of 300 adult patients affected by bone and joint infections. Each classification only focused, on the average, on 1.3 ± 0.4 features of a single clinical condition (osteomyelitis, implant-related infections, or septic arthritis), being able to classify 34.8 ± 24.7% of the patients, while a comprehensive classification system could describe all the patients considered in the study. RESULT AND CONCLUSION: A comprehensive classification system permits more accurate classification of bone and joint infections in adults than any single classification available and may serve for didactic, scientific, and clinical purposes.

Healing of surgical site after total hip and knee replacements show similar telethermographic patterns.

BACKGROUND: Isolated reports indicate the efficacy of infrared thermography for monitoring wound healing and septic complications, but no long-term analysis has ever been performed on this, and there are no data on the telethermographic patterns of surgical site healing after uncomplicated total hip prosthesis and after knee prosthesis. MATERIALS AND METHODS: In this prospective, observational, nonrandomized cohort study, two groups with forty consecutive patients each, who were operated on respectively for total hip and for total knee replacements, underwent telethermographic examination of the operated and contralateral joints prior to and at fixed intervals for up to 1 year after uncomplicated surgery. A digital, portable telethermocamera and dedicated software were used for data acquisition and processing. RESULTS: No thermographic difference was observed preoperatively between the affected side and the contralateral side in both groups. After the intervention, a steep increase in the temperature of the operated joint was recorded after total hip replacement and after knee replacement, with a peak mean differential temperature measured three days postoperatively between the operated and unoperated joint of 3.1 ± 0.8°C after total hip replacement, and 3.4 ± 0.7°C after total knee replacement. Thereafter, the mean differential temperature declined slowly to 0.7 ± 1.1°C and to 0.5 ± 1.3°C at 60 days, and to 0.0 ± 1.0°C and -0.1 ± 1.1°C 90 days post-operatively, respectively. No further changes were observed for up to 1 year after surgery. Results were similar when comparing the average telethermographic values of an elliptical area where the main axis corresponded to the surgical wound. CONCLUSIONS: The surgical sites after uncomplicated total hip or total knee replacement show similar telethermographic patterns for up to 1 year from surgery, and can easily be monitored using a portable, digital, telethermocamera.