No association between positive intraoperative allograft cultures and infection rates after reconstructive knee ligament surgery.

BACKGROUND: Several reports of severe infections associated with allograft tissue in knee reconstructive surgery have led many surgeons to consider routine intraoperative culture of allograft tissue before implantation. Thus, the purpose of this study was to determine the prevalence of positive soft tissue allograft cultures in reconstructive knee surgery, and evaluate its association with surgical site infection. METHODS: Retrospective study of 202 patients who underwent knee reconstructive ligament surgeries, including revisions, between January 2013 and July 2017. Intraoperative culture results were obtained and the report of a surgical site infection during follow-up was recorded. Patients without cultures were excluded. A priori power analysis was performed. The association between positive culture results and development of surgical site infection was evaluated using Fisher's Exact test (P < 0.05). RESULTS: A total of 300 allografts were implanted in 202 patients. Mean average follow-up was 32.9 ±â€¯12.5 (range 13 to 57.9) months. Sixteen patients had positive intraoperative allograft cultures (7.9%). The most frequently isolated organism was Bacillus species (six cultures); none of these patients presented with clinical signs of infection. Nine patients developed surgical site infections and were treated with oral antibiotics, and one patient developed septic arthritis that required surgical debridement of the implanted graft; all of these patients had a negative soft tissue allograft culture. No significant association was found between a positive culture and surgical site infection (P = 0.43). CONCLUSION: There was no apparent association between positive intraoperative irradiated soft tissue allograft cultures and surgical site infection in reconstructive knee surgery.

Presence of Bacteria in Spontaneous Achilles Tendon Ruptures.

BACKGROUND: The structural pathology of Achilles tendon (AT) ruptures resembles tendinopathy, but the causes remain unknown. Recently, a number of diseases were found to be attributed to bacterial infections, resulting in low-grade inflammation and progressive matrix disturbance. The authors speculate that spontaneous AT ruptures may also be influenced by the presence of bacteria. HYPOTHESIS: Bacteria are present in ruptured ATs but not in healthy tendons. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients with spontaneous AT ruptures and patients undergoing anterior cruciate ligament (ACL) reconstruction were recruited for this study. During AT surgical repair, excised tendinopathic tissue was collected, and healthy tendon samples were obtained as controls from hamstring tendon grafts used in ACL reconstruction. Half of every sample was reserved for DNA extraction and the other half for histology. Polymerase chain reaction (PCR) was conducted using 16S rRNA gene universal primers, and the PCR products were sequenced for the identification of bacterial species. A histological examination was performed to compare tendinopathic changes in the case and control samples. RESULTS: Five of 20 AT rupture samples were positive for the presence of bacterial DNA, while none of the 23 hamstring tendon samples were positive. Sterile operating and experimental conditions and tests on samples, controlling for harvesting and processing procedures, ruled out the chance of postoperative bacterial contamination. The species identified predominantly belonged to the Staphylococcus genus. AT rupture samples exhibited histopathological features characteristic of tendinopathy, and most healthy hamstring tendon samples displayed normal tendon features. There were no apparent differences in histopathology between the bacterial DNA-positive and bacterial DNA-negative AT rupture samples. CONCLUSION: The authors have demonstrated the presence of bacterial DNA in ruptured AT samples. It may suggest the potential involvement of bacteria in spontaneous AT ruptures.

Debridement and Functional Rehabilitation for Achilles Tendon Infection Following Tendon Repair.

BACKGROUND: An infected Achilles tendon after tendon repair is particularly difficult to treat because of the poor vascularity of the tendon as well as the thin surrounding soft tissue. For treatment of an infected Achilles tendon following tendon repair, we first focused on complete debridement and then promoted fibrous scar healing of the Achilles tendon using functional treatment. METHODS: We retrospectively reviewed all of the medical records of 15 tertiary referral patients with postoperative infection of the Achilles tendon occurring between 2007 and 2012. The mean follow-up time was 33 months (range, 22 to 97 months). The infected tissue and the necrotic tendon were debrided, and the ankle was placed in a short leg splint for 2 weeks. The splint was then replaced with an ankle brace for the next 4 weeks. Partial weight-bearing was allowed immediately, and full weight-bearing was allowed at 2 weeks postoperatively. We assessed and recorded the physical parameters such as the range of motion, calf circumference, ability to perform a single-limb heel rise, patient satisfaction, and Arner-Lindholm scale. Laboratory tests, postoperative ultrasonography, and isokinetic plantar flexion power tests were also performed. RESULTS: At a mean time of 17 days (range, 8 to 30 days) after debridement, infection signs such as discharge from the wound, redness, and local warmth resolved. The wound had healed and the stitches were removed at a mean of 17 days following the wound repair. At the time of the latest follow-up, there were no signs of active infection. Achilles tendon continuity recovered in all patients by fibrous scar healing. Compared with the contralateral side, there was no difference in the ankle range of motion in 8 patients. According to the Arner-Lindholm scale, 9 of the 15 results were excellent and 6 were good. Ten patients were able to perform a single-limb heel rise. Eleven of 15 patients returned to their pre-injury recreational activities. Diffuse homogeneous echotexture of the Achilles tendon with continuity was observed on the ultrasonographic examination. CONCLUSIONS: In this retrospective series, radical debridement, combined with antibiotic therapy and functional rehabilitation, was successful in eradicating infection and maintaining function in patients with postoperative infection following Achilles tendon repair. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Achilles tendon infection due to Mycobacterium chelonae.

Atypical tuberculous tenosynovitis of the foot and ankle is extremely rare. The determination of the Mycobacterium species is essential because resistance of atypical mycobacterial strains to antituberculous drugs is often encountered. We report a case of Mycobacterium chelonae paratendinous and intratendinous infection involving the Achilles tendon. Repeat aggressive irrigation and debridement procedures, coupled with removal of foreign materials and the appropriate use of prolonged antibiotic therapy, can result in a successful long-term outcome.

Qualitative analysis of substance P, NK1-receptor and nerve ingrowth in substance P-treated ruptured rat Achilles tendon.

Substance P has a stimulating effect on fibroblast proliferation, collagen organization, and angiogenesis in ruptured and subsequently sutured rat Achilles tendon. This effect is also reflected in the biomechanical properties of the tendon. The aim of this study was to substantiate the effect of exogenous substance P on endogenous substance P, NK-1 receptor, and nerve ingrowth in an in vivo tendon-healing setting. Ninety-six male Sprague-Dawley rats were randomly assigned to one of four groups and injected with saline, substance P (10(-6) micromol/kg BW and 10(-8) micromol/kg BW) associated with neutral endopeptidase inhibitors, or neutral endopeptidase inhibitors alone into the paratendinous region of the ruptured and subsequently sutured Achilles tendons from the second until the sixth day postoperatively. Substance P, NK-1 receptor, and nerve ingrowth (PGP 9.5) were analysed using immunofluorescence at four different time points: one, two, four and six weeks postoperatively. In all groups substance P was predominantly expressed in the extracellular matrix during the first two weeks, corresponding to fibroblast proliferation, and first disappeared from the saline group in the proliferative phase. In contrast, substance P was not expressed in the blood vessel wall during the first two weeks, when angiogenesis was most pronounced. NK-1 receptor was almost always expressed in the blood vessel wall and in the extracellular matrix during this period and disappeared progressively afterwards. No nerve ingrowth was identified. Exogenously administered substance P in sutured rat Achilles tendon rupture does not stimulate sensory nerve ingrowth, but seems to have a booster effect on endogenous substance P for fibroblast proliferation via autocrine/paracrine stimulation.

Intratendinous septic abscess of the Achilles tendon after local steroid injection.

UNLABELLED: In the treatment of pathological processes of the skeletal system, local injection of corticosteroid has become a common form of treatment. Although rare, pyogenic abscess can develop secondary to local corticosteroid injection. In this article, we describe the case of a patient who presented with pain, swelling, and hyperemia following local infiltration of corticosteroid about the Achilles tendon. Magnetic resonance image scanning of the Achilles tendon revealed a smoothly shaped intratendinous mass 3 x 1 cm in diameter, extending to the posterosuperior aspect of the calcaneus. A needle aspiration of the suspected abscess revealed S aureus, and subsequent surgical drainage and debridement revealed chronic inflammation secondary to infection at the site of previous local corticosteroid injection. Antibiotic therapy was used following incision and drainage, and recurrence of infection was not detected throughout the duration of follow-up. LEVEL OF CLINICAL EVIDENCE: 4.

Open infected Achilles tendon injury--reconstruction of tendon with fascia lata graft and soft tissue cover with a reverse flow sural flap.

We present a patient with an open, infected Achilles tendon injury with a soft tissue defect of 12 cm x 5 cm and a tendon defect of 10 cm. He underwent a two-stage procedure. A first stage debridement of tendon and soft tissue was followed by a second stage tendo Achilles reconstruction using fascia lata graft and soft tissue cover with a reverse flow sural flap. He had a good functional outcome with minimal donor site morbidity.

Achilles tendinitis in Vibrio vulnificus sepsis: a rare presentation.

Vibrio vulnificus infection commonly presents as sepsis or wound infection. A case of alcoholic liver cirrhosis developed acute left heel pain and swelling 2 days after ingesting raw fish. Two sets of blood cultures indicated V. vulnificus. HLA-B27 was negative. Ultrasonography revealed left Achilles tendinitis. Fluid aspirated from the left retrocalcaneal bursa was sterile. The patient recovered completely 3 weeks after treatment. To our knowledge, V. vulnificus septicaemia with Achilles tendinitis, which may be the only indication of reactive arthritis (ReA), has not been reported previously. Prompt recognition of this life-threatening infection and adequate treatment with antibiotics is vital.

Physiological Achilles' heels of enteropathogenic bacteria in livestock.

An elaborate feeding regimen of animals, which takes advantage of the Achilles' heels of enteropathogenic bacteria, can possibly enable prophylaxis in the intestinal tract, attenuate actual disease symptoms, accelerate recovery from a bacterial gastroenteritis or ensure food safety. There is a wide spectrum of conceivable weak spots in bacteria. Some pathogenic bacteria cannot use certain compounds, or use them less efficient than beneficial bacteria. By addition of such substances to animal feed, non-pathogenic bacteria can grow better than pathogens and competitively exclude the latter ones. Other compounds even have an inhibitory effect on pathogens. Calcium phosphate for example protects against Salmonella, Zn2+ has a prophylactic effect against Brachyspira, and Fe2+ has an inhibiting effect on the enterotoxin synthesis of Yersinia enterocolitica. Besides, there are antimicrobial substances as plant extracts, essential oils, organic acids and other compounds, which inhibit pathogens more than other bacteria. A simultaneous application of several anti-pathogen agents suggest an enhanced effect. Some countermeasures aim at a distinct group of bacteria, while others are more universal. General strategies to repel different pathogenic bacteria are the supply of health-stimulating milk components, antagonistic bacteria for competitive exclusion, and mucus-related attractants for misguidance of adhering and invasive bacteria. This paper gives an overview of Achilles' heels of enteropathogenic bacteria that can be exploited to develop strategies for keeping control over these pathogens in the gastrointestinal tract of livestock.