Daniel Pérez-Prieto

Improved Diagnosis of Orthopedic Implant-Associated Infection by Inoculation of Sonication Fluid into Blood Culture Bottles

ABSTRACT Sonication improved the diagnosis of orthopedic implant-associated infections (OIAI). We investigated the diagnostic performance of sonication fluid inoculated into blood culture bottles in comparison with that of intraoperative tissue and sonication fluid cultures. Consecutive patients with removed orthopedic hardware were prospectively included and classified as having OIAI or aseptic failure (AF) according to standardized criteria. The diagnostic procedure included the collection of five intraoperative tissue cultures and sonication of the removed device, followed by conventional culture of the sonication fluid. Cultures were incubated for 7 days (aerobic) or 14 days (anaerobic). In addition, 10 ml of sonication fluid was inoculated into each aerobic and anaerobic BacT/Alert FAN blood culture bottle and incubated in the automated blood culture system for 5 days. Of 75 included patients, 39 had OIAI and 36 AF. The sensitivity of sonication fluid inoculated into blood culture bottles (100%) was higher than that of conventional sonication fluid (87%; P = 0.05) or intraoperative tissue cultures (59%; P < 0.01). Previous antibiotic therapy reduced the culture sensitivity of conventional sonication fluid to 77% and that of intraoperative tissue to 55%, while it remained 100% for blood culture-inoculated sonication fluid. The time to positivity was shorter in blood culture-inoculated sonication fluid, with detection of 72% of microorganisms after 1 day of incubation, than for intraoperative tissue and conventional sonication fluid cultures, with detection of 18% and 28% of microorganisms, respectively. In conclusion, compared to conventional sonication fluid and intraoperative tissue cultures, sonication fluid inoculated into blood culture bottles improved the diagnosis of OIAI and considerably reduced the time to culture positivity.

Influence of Depression on Total Knee Arthroplasty Outcomes

It is not clear whether indicating TKA-surgery is advisable in depressed patients. A prospective cohort of 716 patients undergoing TKA was designed. SF36, KSS, WOMAC and VAS plus 2 satisfaction questions were evaluated. There were 2 groups: 200 patients were depressed and 516 were not. Preoperative/postoperative results show better scores for non-depressed patients on almost every sub-scale. Nevertheless, net change results (improvement) were quite similar: 65.74 improvement in depressed-KSS and 74.58 in non-depressed (P=0.049); 8.93 net change in depressed-Physical Composite Score and 11.84 in non-depressed (P=0.003); 2.38 in depressed-Mental Composite Score and -0.61 in non-depressed (P=0.024). Depressed patients obtained great improvement from preoperative at one-year follow-up and even greater than non-depressed patients in some domains. Moreover, satisfaction was similar. Therefore, TKA can be recommended to depressed patients.

Preoperative antibiotic prophylaxis in prosthetic joint infections: not a concern for intraoperative cultures

BACKGROUND Culture negative prosthetic joint infections (PJI) still remain an issue even with the advantages of the new diagnostic tools for PJI. This is why some orthopedic surgeons have reservations relative to the use of preoperative antibiotic prophylaxis when a PJI is suspected. The purpose of the present study was to evaluate the influence of preoperative antibiotic prophylaxis on intraoperative cultures. MATERIAL AND METHODS An enhanced diagnostic protocol for PJI (Zimmerli criteria) was used for the inclusion criteria in order to collect all PJI that were seen in a university hospital. Patients were prospectively randomized into two groups. The control group received the classical preoperative antibiotic prophylaxis. The study group did not receive prophylaxis prior to surgery. RESULTS There were 14 patients in each group. They correspond to 13 total hip arthroplasty infections, 12 total knee arthroplasty infections and 3 reverse shoulder prosthesis infections. There were 10 patients in the study group and 10 patients in the control group with at least one positive microbiological criterion (P > 0.05). There were 4 patients in each group with a culture negative PJI (P > 0.05). CONCLUSIONS Preoperative antibiotic prophylaxis does not affect intraoperative cultures in suspected or confirmed PJI. Therefore it is essential to deliver antibiotic prophylaxis in any patient in which a prosthesis is to be implanted in order to protect the prosthesis from infection.

Sealing of the intramedullar femoral canal in a TKA does not reduce postoperative blood loss: A randomized prospective study

BACKGROUND Sealing of the femoral canal, usually with autologous bone, is a surgical procedure that is often performed during TKA surgery to decrease blood loss in the postoperative period. However, evidence as to the effectiveness of this surgical procedure is not conclusive. The objective of this study was to assess the effectiveness of this surgical action in reducing postoperative blood loss and the blood transfusion rate. METHODS A randomized prospective study that included 201 TKAs divided into three groups (67 in each one) was carried out. The three groups were; A) bone graft sealing, B) cement sealing and C) unsealed canal. All groups were comparable with regard to pre and intra-operative data. The haemoglobin decrease at 2, 24 and 72 h was compared to the preoperative haemoglobin value. Subsequently, blood drainage at 12 and 24h and the rate of blood transfusion were also assessed. The different complications that arose were reported. RESULTS No statistical differences were obtained with regard to blood drainage at 12h (p=0.102) and 24h (p=0.542), the haemoglobin value decrease at 72 h (p=0.95) and the number of blood transfusions (p=0.597) in the three groups studied. CONCLUSION There was no significant difference, whether sealing the femoral canal with a bone graft, cement or when it was left unsealed, in decreasing blood loss or blood transfusion requirements in the postoperative period. LEVEL OF EVIDENCE Therapeutic type I.

Managing septic arthritis after knee ligament reconstruction.

PurposeJoint infection after anterior cruciate ligament (ACL) reconstruction is uncommon but has potentially serious consequences for the graft and articular cartilage. Most recently published series are in agreement that an urgent arthroscopic washout and antibiotic treatment are mandatory to preserve both graft and cartilage. However, several questions have not as yet been touched upon.MethodsWe performed a literature review to assess the most interesting series published about this issue.ResultsIn this review, a management protocol is first presented that discusses the different diagnostic parameters to consider and surgical and antibiotic treatment suggested according to the literature. Outcomes published in different series are also discussed.

Influence of Hindfoot Malalignment on Hallux Valgus Operative Outcomes

Background: Hindfoot deformity has been described as a risk factor for poor hallux valgus (HV) surgery outcomes. However, there has been no study that demonstrates it. The purpose of this investigation was to evaluate the influence of hindfoot misalignment in HV surgery results. Methods: All patients operated on for HV during 2010 and 2011 at 3 university hospitals were included. The preoperative and 2-year postoperative radiologic data included the HV and the intermetatarsal (IM) angles, the naviculocuboid overlap (NC), the talonavicular coverage (TN) angle, the talus–first metatarsal (T-1MT) angle, as well as the calcaneal pitch (CP) angle. Additionally, the Short Form–36 questionnaire version 2.0 (SF-36) and the American Orthopaedic Foot & Ankle Society (AOFAS) score, satisfaction and recurrence were also analyzed. A total of 207 met the inclusion criteria. There were 26 patients (12.6%) who could not be assessed at the 2-year follow-up. Patients were allocated to a varus, normal, or a valgus hindfoot tertile using the values for the CP, NC, TN, and T-1MT angles. Results: No significant differences (P > .05) were found between the groups when the HV or IM angles, AOFAS, SF-36 Mental Composite Scale, SF-36 Physical Composite Scale, or satisfaction were compared. Similarly, no significant and strong correlations were observed (P > .05, ρ < 0.3) between any of the mentioned hindfoot measures and the outcomes scales. Conclusion: No influence of hindfoot misalignment on HV surgery outcomes was found in the present study in terms of correction, pain, function, satisfaction, or quality of life. Patients with hindfoot misalignment did not obtain worse outcomes in HV surgery. Level of Evidence: Level II, prognostic, comparative study.

Relationship of Plantar Fascia Thickness and Preoperative Pain, Function, and Quality of Life in Recalcitrant Plantar Fasciitis:

Background: The measurement of plantar fascia thickness has been advocated as a diagnostic and prognostic instrument in patients with plantar fasciitis, but there are no data relative to it in recalcitrant plantar fasciitis. The aim of the study is to evaluate the correlation between plantar fascia thickness and pain, functional score, and health perception in patients with this condition. Methods: Thirty-eight feet were studied with ultrasound and magnetic resonance imaging to measure plantar fascia thickness. The visual analogue scale (VAS), American Orthopaedic Foot & Ankle Society Hindfoot Score (AOFAS), and SF-36 were then recorded for each patient. The relationship between the fascia and these scores was analyzed to evaluate the correlation of thickness with pain, functional level, and health perception of patients. Results: In patients with recalcitrant plantar fasciitis, plantar fascia thickness did not correlate with pain (VAS), AOFAS, or any item of the SF-36. Conclusion: The thickness of the plantar fascia in patients with recalcitrant plantar fasciitis did not correlate with its clinical impact, and thus, we believe it should not be used in treatment planning. Level of Evidence: Level IV, case series.

Foot and ankle infections: Debridement, early fixation and rifampicin provide earlier recovery of function and quality of life

BACKGROUND Infection after foot and ankle fractures is a major concern for orthopedic surgeons. It is widely believed that final osteosynthesis should be delayed until the infection is cured. However, there is no literature that supports this practice. In addition, the delay impairs patient function and quality of life (QoL). METHODS In the present study, four cases of ankle infection treated with aggressive debridement, early fixation and antibiofilm antibiotics are described. It is thought that, like other implant related infections, ankle infections can be rapidly treated with the definitive fixation and by curing the infection to make for a fast recovery of QoL and function. RESULTS The infections were caused by MSSA and Pseudomonas aeruginosa in case 1, MSSA in case 2 and MRSA as well as K. pneumonia in case 3. Case 4 was a culture negative infection. They were susceptible to antibiofilm antibiotics (the gram-negative bacilli susceptible to ciprofloxacin and the gram-positive cocci susceptible to rifampicin). Cases 1, 3 and 4 were treated with a tibio-talo-calcaneal arthrodesis and case 2 was treated with a de-rotational fibular osteotomy and a medial closing wedge supramalleolar osteotomy. All cases improved at a median time of 4 weeks in terms of quality of life (SF-36) and function (AOFAS). At 2-years follow-up, no recurrence of infection was observed in any of the cases. All the cases achieved fusion or osteotomy healing at final follow-up. CONCLUSIONS Early fixation after debridement combined with antibiofilm antibiotics can be performed in foot and ankle inflections to provide early recovery of QoL and function in patients.

Corticosteroid Injection for the Treatment of Morton’s Neuroma: A Prospective, Double-Blinded, Randomized, Placebo-Controlled Trial

Background: The effectiveness of corticosteroid injection for the treatment of Morton’s neuroma is unclear. In addition, most of the studies related to it are case-control or retrospective case series. The purpose of this study was to compare the effectiveness between corticosteroid injection associated with local anesthetic and local anesthetic alone (placebo control group) for the treatment of Morton’s neuroma. Methods: Forty-one patients with a diagnosis of Morton’s neuroma were randomized to receive 3 injections of either a corticosteroid plus a local anesthetic or a local anesthetic alone. The patients and the researcher who collected data were blinded to the treatment groups. The visual analog scale for pain and the American Orthopaedic Foot & Ankle Score (metatarsophalangeal/interphalangeal score) were obtained at baseline, after each injection, and at 3 and 6 months after the last injection. Results: There were no significant between-group differences in terms of pain and function improvement at 3 and 6 months after treatment completion in comparison with baseline values. At the end of the study, 17 (48.5%) patients requested surgical excision of the neuroma: 7 (44%) in the experimental group and 10 (53%) in the control group (P = 1.0). Conclusion: The injection of a corticosteroid plus a local anesthetic was not superior to a local anesthetic alone in terms of pain and function improvement in patients with Morton’s neuroma. Level of Evidence: Level I, randomized controlled trial.