Surgical site infection in spinal surgery: detection and management based on serial C-reactive protein measurements

Epidural spread of surgical site infection from spinal cord stimulation trial

We present a case of deep surgical site infection (SSI) at a spinal cord stimulator (SCS) trial implantation site, resulting from an allergic reaction to an unknown agent. A 38-year-old female with complex regional pain syndrome began an SCS trial, noting 100% pain relief for 5 days. Fluid drainage from the surgical site was reported on POD6 and trial leads were removed the following day. The patient was hospitalized with sepsis. Blood cultures revealed Staphylococcus aureus. MRIs showed skin breakdown and cellulitis of the paraspinal musculature extending into the epidural space. The patient was maintained with antibiotics and rigorous wound care for 9 days and the surgical site infection resolved. The patient proceeded to SCS implantation, and reported good pain relief with the implanted device.

Logistic regression model predicts early surgical site infection after spinal fusion: a retrospective cohort study

OBJECTIVE

This study aimed to develop a diagnostic model for predicting early surgical site infection (SSI) based on postoperative inflammatory markers after spinal fusion surgery.

METHODS

In this retrospective study, we analysed the trends of inflammatory markers between SSI and non-SSI groups. The data were randomly divided into training cohort and validation cohort (ratio 7:3). The variables for SSI were analysed using stepwise logistic regression to develop the prediction model. To evaluate the model, we analysed its sensitivity, specificity, positive predictive value, negative predictive value, as well as the area under the curve in the validation cohort. Calibration plots and decision curve analysis were employed to assess the calibration and clinical usefulness of the model.

FINDINGS

We observed significant changes in inflammatory markers on the seventh day after surgery. The prediction model included four variables on the seventh day after surgery: body temperature, C-reactive protein, erythrocyte sedimentation rate and neutrophil counts. After binary processing of these data, the simplified model achieved an area under the curve of 0.86 (95% confidence interval (CI): 0.81-0.92) in the training cohort and 0.9 (95% CI: 0.82-0.98) in the validation cohort. Calibration plots and decision curve analysis demonstrated that the proposed model was effective for the diagnosis of SSI.

CONCLUSION

We developed and validated a prediction model for diagnosing early infection after spinal fusion.

Is an Elevated Preoperative CRP Level a Predictive Factor for Wound Healing Disorders following Lumbar Spine Surgery?

Postoperative wound infections are a prevalent concern among the hospital-associated infections in Europe, leading to prolonged hospital stays, increased morbidity and mortality, and substantial patient burdens. Addressing the root causes of this complication is crucial, especially given the rising number of spine surgeries due to aging populations.

METHODS

A retrospective analysis was conducted on a cohort of 3019 patients who underwent lumbar spine surgery over a decade in our department. The study aimed to assess the predictors of wound healing disorders, focusing on laboratory values, particularly inflammatory parameters.

RESULTS

Of the 3019 patients, 2.5% (N = 74) experienced deep or superficial wound healing disorders, showing the significant correlation between C-reactive protein (CRP) levels and these disorders (p = 0.004). A multivariate analysis identified several factors, including age, sex, hypertension, diabetes, cardiac comorbidity, surgical duration, dural injury, and blood loss, as being correlated with wound healing disorders.

CONCLUSION

Demographic factors, pre-existing conditions, and perioperative variables play a role in the occurrence of adverse effects related to wound healing disorders. Elevated CRP levels serve as an indicator of increased infection risk, though they are not a definitive diagnostic tool for wound healing disorders.

Post-Discectomy Infection: A Critical Review and Suggestion of a Management Algorithm

Postoperative discitis (POD) accounts for 20% to 30% of all cases of pyogenic spondylodiscitis, while POD may be mis-or-under-diagnosed, due to the vague related symptomatology and the non-specific imaging findings. Most studies report infection rate of less than 1%, which increases with the addition of non-instrumented fusion to 2.4% to 6.2%. It remains controversial whether POD is caused by an aseptic or infectious process. Positive cultures are presented only in 42-73% of patients with Staphylococcus species being the most common invading organisms, while Staphylococcus aureus is isolated in almost 50% of cases. The onset of POD symptoms usually occurs at 2-4 weeks after an apparently uneventful operation. Back pain and muscle spasms are usually refractory to bed rest and analgesics. Magnetic Resonance Imaging (MRI) is the most sensitive and specific imaging diagnostic technique. Antimicrobial therapy depends on the results of tissue cultures, and along with bracing represents the mainstay of management. Surgical intervention is necessary in patients failing conservative treatment. For the majority of cases, extensive surgical debridement, antibiotic therapy, and orthosis immobilization are effective in eliminating the infection. According to this, we recommend an Algorithmic approach for the management of POD. Postoperative infections after spinal surgery pose a certain clinical challenge, and in most cases can be treated conservatively. Nevertheless, disability may be persistent, and surgery could be necessary. The purpose of this concise review is to describe the manifestation of post-discectomy infection, its pathogenesis and particularly a rational approach for its management.

Risk Factors for Postoperative Surgical Site Infection in Patients Undergoing Spinal Tumor Surgery

STUDY DESIGN

A retrospective comparative case-control study.

OBJECTIVE

The aim of this study was to determine the risk factors for postoperative surgical site infection (SSI) in patients with spinal tumors requiring reoperation during the perioperative period.

SUMMARY OF BACKGROUND DATA

SSI is a common postoperative complication of spinal surgery. The occurrence of SSI not only increases the mortality rate but prolongs the patient's hospital stay and increases the medical cost.

METHODS

Included in this study were 202 patients with spinal tumors who received surgical treatment between January 2008 and December 2018, of whom 101 patients who developed SSI and underwent secondary surgery were used as the SSI group, and the other 101 patients with no SSI who were matched with the SSI group by age (±10), pathologic diagnosis (malignant/no-malignant), tumor site (C/T/L/S), surgical approach (anterior/posterior/combined), and surgical team were used as the control group. The clinical data of the 202 patients in both groups were analyzed by logistic regression modeling to identify SSI-associated risk factors.

RESULTS

Multivariate logistic regression analysis showed that the revision status ( B =1.430, P =0.028), the number of spinal levels fused ≥4 ( B =0.963, P =0.006), and the use of bone cement ( B =0.739, P =0.046) were significantly associated with the increased risk of developing postoperative SSI.

CONCLUSIONS

This study identified the revision status, the number of spinal levels fused ≥4, and the use of bone cement as independent risk factors for SSI in patients with spinal tumors who underwent reoperation during the perioperative period.

Instrument shank-assisted ovariohysterectomy: a randomized clinical trial of surgical and pain alleviation efficiency of a single-person modified technique

Objectives

To evaluate a modified ovariohysterectomy (OHE) technique performed by a single person and compare it with the conventional method based on time efficiency, trauma, and postoperative pain.

Methods

In a prospective, randomized, experimental study, 18 healthy, large, deep-chested, mixed-breed intact female dogs were randomly allocated to conventional (n = 9) and instrument shank-assisted (n = 9) groups. On the basis of video recordings, the various surgical step durations were analyzed: total surgery time (TST), pedicle intervention time (PIT), suspensory release time (SRT), shanking time (ShT), clamping time (ClpT), ligating time (LigT), and closure time (CT). The Glasgow composite pain scale short-form (GCMPS-SF), university of Melbourne pain scale (UMPS), and Visual Analogue Scales (VAS) were used to measure pain. C-reactive protein (CRP) fluctuation was also investigated. These evaluations were completed before and 6, 24, 48, and 72 h postoperatively.

Results

Instrument shank-assisted OHE was less time-consuming than conventional OHE (p = 0.005), improved PIT by 30.7% (6.44 min for both pedicles, p = 0.014), and correlated strongly with TST (ρ = 0.862, p = 0.003 and ρ = 0.955, p = 0.000, respectively). The two method's surgical step durations were also TST = 47.40 ± 9.9 vs. 34.70 ± 6.7 min, PIT = 20.96 ± 5.78 vs. 14.52 ± 3.73 min, SRT = 78.97 ± 69.10 vs. ShT = 20.39 ± 8.18 s (p = 0.035), ClpT = 50.66 ± 45.04 vs. 63.55 ± 37.15 s (p = 0.662), LigT = 12.82 ± 3.37 vs. 8.02 ± 3.11 min (p = 0.005), and CT = 16.40 ± 4.5 vs. 11.60 ± 2.5 min (p = 0.013), respectively. While both techniques inflicted pain on the animals, the novel approach resulted in a reduction of pain at T6 (GCMPS-SF, p = 0.015 and VAS, p = 0.002), T24 (UMPS, p = 0.003), and T48 (GCMPS-SF, p = 0.015 and UMPS, p = 0.050). Both methods exhibited a peak in CRP level after 24 h, which subsequently returned to baseline after 48 h. However, the shank-assisted method demonstrated a significantly lower reduction in CRP level at the 48-h compared to the other group (p = 0.032).

Conclusion

Instrument shank-assisted technique permitted ovarian removal without an assistant, less damage to animals and reducing its time when compared to a conventional technique, and resulting in an alternative that causes less surgical stress and fatigue. Further research with a larger population size is required to determine the serum CRP levels as an alternative pain biomarker.

Cervical spine spondylodiscitis: Review of literature on current treatment strategies

Infections of the spine are an ever-increasing health concern requiring an often complex and prolonged treatment that can lead to significant morbidity. Of particular interest is the cervical spine where there is an increase rate of post-infectious deformity, secondary neurological deficits and substantially higher rates of associated morbidity and mortality than the thoracic or lumbar spine. In this review, we explore the diagnosis and treatment of spondylodiscitis with particular focus on the cervical spine.

A prospective study to identify preoperative serum parameters for spinal implant infection detected by sonication fluid culture

PURPOSE

Low-virulent microorganisms identified on pedicle screws by sonication fluid culture (SFC) are an important cause of implant loosening. While sonication of explanted material improves the detection rate, the risk of contamination exists and no standardized diagnostic criteria for chronic low-grade spinal implant-related infection (CLGSII) are stablished. Besides, the role of serum C-reactive protein (CRP) and procalcitonin (PCT) in CLGSII has not been adequately investigated.

METHODS

Blood samples were collected prior to implant removal. To increase sensitivity, the explanted screws were sonicated and processed separately. Patients exhibiting at least one positive SFC were classified in the infection group (loose criteria). To increase specificity, the strict criteria only considered multiple positive SFC (≥ 3 implants and/or ≥ 50% of explanted devices) as meaningful for CLGSII. Factors which might promote implant infection were also recorded.

RESULTS

Thirty-six patients and 200 screws were included. Among them, 18 (50%) patients had any positive SFCs (loose criteria), whereas 11 (31%) patients fulfilled the strict criteria for CLGSII. Higher serum protein level was the most accurate marker for the preoperative detection of CLGSSI, exhibiting an area under the curve of 0.702 (loose criteria) and 0.819 (strict criteria) for the diagnosis of CLGSII. CRP only exhibited a modest accuracy, whereas PCT was not a reliable biomarker. Patient history (spinal trauma, ICU hospitalization and/or previous wound-related complications) increased the likelihood of CLGSII.

CONCLUSION

Markers of systemic inflammation (serum protein level) and patient history should be employed to stratify preoperative risk of CLGSII and decide the best treatment strategy.

Spondylodiscitis-a cohort analysis of its identification and management

PURPOSE

Discitis represents infection of the intervertebral disc and osteomyelitis of the adjacent end plates. Classically, patients present with fever and back pain. Varied presentations and lack of adherence to guidelines lead to great variation in its identification and management. The primary objective of this study was to conduct a cohort analysis, assessing the identification and management of discitis, in a busy secondary orthopaedic centre.

METHODS

A retrospective study was conducted, of cases diagnosed and treated for discitis, in a secondary orthopaedic department, within the UK from January 2017 to October 2019. During this time period, all patients who underwent magnetic resonance imaging (MRI) spine were identified. Patients with MRI-proven discitis were then added into the study.

RESULTS

A total of 152 MRIs showed radiographic features of discitis. Of these, only 38 had a clear clinical correlation. Back pain was the most common presenting complaint followed by fever. The commonest site of involvement was vertebral levels L5 and S1. All patients had baseline bloods, and most, but not all, had blood cultures taken. Staphylococcus aureus was the most frequently isolated, causative organism. The mainstay of treatment was intravenous flucloxacillin, with most patients requiring a minimum of six weeks.

CONCLUSION

Our study has helped define the population of patients presenting with discitis, in a busy secondary orthopedic center. Analyzing over two years of data has provided us with valuable insight into the most appropriate diagnostics and management for discitis.

Risk Factors and Outcomes of Central Nervous System Infection After Spinal Surgery: A Retrospective Cohort Study

OBJECTIVE

To investigate the risk factor associated with central nervous system infection, a rare and dire complication after spinal surgery.

METHODS

Univariate and multivariate logistic regression analyses were performed to screen for the independent risk factors. According to the different administration methods of antibiotics, patients were divided into intravenous and intrathecal groups. The differences in time needed for body temperature, white blood cells (WBC), and C-reactive protein (CRP) to return to normal and the time of antibiotic application were compared between the 2 groups. In addition, the differences in WBC, neutrophil ratio, CRP, procalcitonin in blood, and WBC in cerebrospinal fluid were compared before intrathecal injection, after the first one, and the last one. The incidence of complications in the 2 groups was observed.

RESULTS

Dural tears, laminectomy, and operation time >3 hours were identified as independent risk factors. The time needed for body temperature, WBC, and CRP to return to normal and the antibiotic application time were significantly different between the 2 groups (all P < 0.05). Before and after the first intrathecal injection and after the last intrathecal injection, the differences in WBCs, neutrophil ratios, CRP, procalcitonin in blood, and cerebrospinal fluid-WBC were statistically significant in overall and pairwise comparisons (P < 0.05). Complications occurred in 2 and 14 cases, respectively.

CONCLUSIONS

The independent risk factors for central nervous system infection after spinal surgery were a dural tear, laminectomy, and operation time > 3 hours. Combined intravenous and intrathecal injections of antibiotics led to a better effect than intravenous injection alone; however, this approach was associated with more complications.

Clinical safety study of photobiomodulation in acute spinal cord injury by scattering fiber

The study aimed to design a reliable and straightforward PBM method by implanting a medical scattering fiber above surgically exposed spinal cord in SCI patients. Moreover, the safety of this method was examined. Twelve patients with acute SCI (ASIA B) requiring posterior decompression were recruited. The medical scattering fiber was implanted above the spinal cord, and was continuously irradiated at 810 nm, 300 mW, 30 min/day, once per day for 7 days. The vital signs (temperature, blood pressure, respiratory rate, heart rate, and oxygen saturation), infection indicators (WBC, NEUT, hs-CRP, and PCT), photo-allergic reaction indicators (Eosinophil and Basophil), coagulation function indicators (PT, APTT, TT) and neurological stability indicators (ASIA sensory and motor scores) were recorded to evaluate the safety of PBM. Three months after surgery, 12 patients completed follow-up. In our study, direct PBM on SCI site did not cause clinically pathologic changes in vital signs of the patients. All patients had higher WBC, NEUT, and hs-CRP at day 3 during irradiation than those before surgery, and returned to normal at day 7. The changes in Eosinophil and Basophil that were closely associated with allergic reactions were within normal limits throughout the course of irradiation. The coagulation function (PT, APTT, and TT) of patients were also in the normal range. The ASIA sensory and motor scores of all patients had no changes throughout the irradiation process. However, in the follow-up, both ASIA sensory and motor scores of all patients had minor improvement than those in pre-irradiation, and 7 patients had adverse events, but they were not considered to be related to PBM. Our study might firstly employ direct PBM in the SCI by using scattered optical fibers. In a limited sample size, our study concluded that direct PBM at the site of SCI would not produce adverse effects within the appropriate irradiation parameters. The method is safe, feasible, and does not add additional trauma to the patient. Our preliminary study might provide a new methodology for the clinical PBM treatment of acute SCI.

Establishment of a suitable combination of serological markers to diagnose surgical site infection following spine surgery: A novel surgical site infection scoring system

BACKGROUND

The accuracy rates of several effective serological markers of surgical site infection following spine surgery are unclear. We aimed to verify the accuracy of each significant marker and identify the most suitable and effective combination of these markers for the diagnosis of surgical site infection following spine surgery.

METHODS

This retrospective study enrolled 329 patients who underwent spine surgery for causes other than infectious spondylitis, including 9 patients with surgical site infection. Complete blood cell count, differential counts, and C-reactive protein levels were measured preoperatively and postoperatively (days 2 and 7). Serological data were compared among non-surgical site infection and surgical site infection cases. Cutoff values for items presenting significant differences were determined using receiver operating characteristic curves. Ratios in each serological factor at each time-point were compared. Combinations of these factors on postoperative day 7 and ratio items were investigated to determine the most suitable combination comprising the least number of items.

RESULTS

Significant differences were noted among four factors on postoperative day 7, except for the lymphocyte count. For the ratio items, significant differences were observed among 6 items. The combination of these ten markers was examined; each factor was assigned 1 point. The most suitable combination comprising 4 items, including neutrophil count, neutrophil-to-lymphocyte ratio, lymphocyte count ratio, and C-reactive protein ratio, presented an AUC of 0.95, with a cutoff value, sensitivity, and specificity of 3 points, 0.89, and 0.92, respectively.

CONCLUSION

The combination of four markers is the most suitable criterion for the surgical site infection scoring system following spine surgery, where scores of ≥3 points strongly indicate surgical site infection. This criterion may be a strong tool for detecting surgical site infection.

Pyogenic and Non-Pyogenic Spinal Infections: Diagnosis and Treatment

Spinal infection (SI) is an infection of vertebral bodies, intervening disc, and/or adjoining para-spinal tissue. It represents less than 10 % of all skeletal infections. There are numerous factors that predispose to developing a SI. Due to the low specificity of signs, delayed diagnosis is common. Hence, SI may be associated with poor outcomes. Diagnosis of SI must be supported by clinicopathological and radiological findings. MRI is a reliable modality of choice. Treatment options vary according to the site of the infection, disease progression, neurology, presence of instability, and general condition of the subject. Conservative treatment (orthosis/ bed-rest + antibiotics) is recommended during the early course with no/ lesser degree of neurological involvement and to medically unfit patients. Nevertheless, when conservative measures alone fail, surgical interventions must be considered. The use of concomitant antimicrobial drugs intravenously during initial duration followed by oral administration is a necessity. Controversies exist regarding the optimal duration of antimicrobial therapy, yet never given less than six weeks. Heterogeneity in clinical picture and associated co-morbidities with a range of treatment modalities are available; however, a common applicable guideline for SI does not exist. Managing SI must be tailored on a case-to-case basis.

A Novel Technique for Treating Early Deep Surgical Site Infection After Posterior Lumbar Fusion with Instrumentation

OBJECTIVE

To introduce a novel technique of using incisional vacuum-assisted closure (VAC) after 1-stage incision suture combined with closed suction irrigation system (CSIS) for treating early deep surgical site infection (SSI) after posterior lumbar fusion with instrumentation and to compare it with traditional CSIS.

METHODS

This was a retrospective study. Patients with early deep SSI after posterior lumbar fusion with instrumentation from January 2013 to May 2020 who were treated by meticulous debridement followed by either CSIS or incisional VAC after 1-stage incision suture combined with CSIS were identified. The demographic characteristics, treatment features, and outcomes were analyzed and compared between the 2 treatment methods.

RESULTS

A total of 48 patients (48/5016, 0.96%) developed early deep SSI, 46 of whom were enrolled in this study. This included 24 patients in the CSIS group (group 1) and 22 patients in the incisional VAC after 1-stage incision suture combined with CSIS group (group 2). All patients received follow-up, with an average of 19.7 months (range, 13-30 months). There were no significant differences in demographic characteristics in both groups (P > 0.05). The number of VAC foam dressing or ordinary dressing changes (P < 0.001), number of debridements (P = 0.028), intravenous antibiotic duration (P = 0.042), oral antibiotic duration (P = 0.019), and hospital stay (P = 0.029) in group 1 were significantly higher than those in group 2. The irrigation duration in group 1 was significantly shorter than that in group 2 (P = 0.007). All patients were eventually cured with satisfactory outcomes.

CONCLUSIONS

Compared with CSIS, incisional VAC after 1-stage incision suture combined with CSIS may be recommended considering that it has fewer dressing changes, fewer debridements, longer irrigation duration, shorter duration of antibiotic use, shorter hospital stay, and more convenient nursing care.

Interleukin-6 as inflammatory marker of surgical site infection following spinal surgery

BACKGROUND

In order to elucidate whether serum inflammatory markers identify patients with local surgical site infection(SSI) as underlying disease for recurrent or new symptomatology following spine surgery, we evaluated the diagnostic potential of interleukin-6(IL-6) as a marker of SSI. The diagnostic significance of IL-6 was compared to the standard serum inflammatory markers C-reactive protein(CRP) and white blood cell count (WBCC).

METHOD

Ninety-eight consecutive patients with readmission due to recurrent or new symptomology after spinal surgery of degenerative spine disorders entered the study. Baseline patients' characteristics and the abovementioned inflammatory markers were collected, and arithmetical means with standard deviation, area under the curve (AUC), thresholds, sensitivity, specificity, positive(+)likelihood ratio (LR), and negative(-)LR with corresponding 95% confidence interval(95%CI) were calculated and correlated with presence or absence of SSI.

RESULTS

Nine patients suffered from a SSI, whereas the remaining 89 patients had a recurrent/adjacent-segment degenerative disorder without evidence of infection. The most significant parameter for diagnosing a SSI was serum IL-6 (cut-off value > 15.3 pg/ml, AUC = 0.954, SE = 85.7%, SP = 97.3%), followed by CRP (cut-off value = 0.8 mg/dl, AUC = 0.916, SE = 88.9%, SP = 84.5%) CONCLUSIONS: In the case of recurrent or new symptomatology following spinal surgery, serum IL-6 has the highest diagnostic potential for diagnosing spinal SSI.

Iatrogenic postoperative spondylodiscitis attributed to Burkholderia cepacia infection in an immunocompetent patient

Background

Pyogenic spondylodiscitis (PS) is a rare infection involving the intervertebral disk space, adjacent vertebral endplates, and vertebral bodies. PS occurs in the elderly and immunocompromised patients, and is an uncommon cause of initial and/or postoperative PS. There are only seven cases involving this organism reported in literature.

Case Description

Here, we present a 35-year-old male who following a lumbar discectomy developed a postoperative iatrogenic PS uniquely attributed to Burkholderia cepacia. The patient was successfully managed with postoperative surgical debridement and antibiotic therapy.

Conclusion

Rarely, B. cepacia may be the offending organism resulting in a postoperative lumbar PS.

Predicting the disaster - The role of CRP in acetabular surgery

OBJECTIVES

Acetabular fractures represent a complex surgical challenge. Given the heterogenous fracture pattern, the patient characteristics and spectrum of complications demand individual solutions. Surgical site infections (SSI) threaten osteosynthesis, and early detection of them and treatment remain crucial. What is the value of postoperative C-reactive protein (CRP) in this group of patients as well as its normal course?

DESIGN & METHODS

115 patients with isolated fractures of the acetabulum were retrospectively evaluated. CRP, white blood cell count (WBC) and fracture patterns as well as patient characteristics were assessed for 20 days following operative fixation of the acetabular fracture (n = 71) and in fractures that were managed conservatively (n = 44).

RESULTS

Twelve patients suffered an infectious complication. With a one-phase decay, 70.55% of the variance of postoperative CRP kinetics was predicted. To anticipate maximum CRP as well as an infection, the preoperative CRP represented the best prognostic parameter. To predict an infection, the single variable "peak CRP value above 100 mg/l" resulted in a sensitivity and specificity of 91.67% and 36.21%, respectively. Combining a second peak of CRP with maximum CRP and day 5 CRP value for receiver-operating characteristic (ROC) analysis resulted in 83.3% and 88.1%, respectively.

CONCLUSIONS

Predicting surgical site infections after an acetabular fracture is most predictive when analyzing the maximum overall CRP, the second peak and the CRP after day 5. With a combination of these parameters, a sensitivity and specificity of 83.3% and 88.1% to detect an infection was achieved.

Dynamic changes in the systemic immune responses of spinal cord injury model mice

Intraspinal inflammatory and immune responses are considered to play central roles in the pathological development of spinal cord injury. This study aimed to decipher the dynamics of systemic immune responses, initiated by spinal cord injury. The spinal cord in mice was completely transected at T8. Changes in the in vivo inflammatory response, between the acute and subacute stages, were observed. A rapid decrease in C-reactive protein levels, circulating leukocytes and lymphocytes, spleen-derived CD4⁺ interferon-γ⁺ T-helper cells, and inflammatory cytokines, and a marked increase in neutrophils, monocytes, and CD4⁺CD25⁺FOXP3⁺ regulatory T-cells were observed during the acute phase. These systemic immune alterations were gradually restored to basal levels during the sub-acute phase. During the acute phase of spinal cord injury, systemic immune cells and factors showed significant inhibition; however, this inhibition was transient, and the indicators of these serious disorders gradually returned to baseline levels during the subacute phase. All experiments were performed in accordance with the institutional animal care guidelines, approved by the Institutional Animal Care and Use Committee of Experimental Animal Center of Drum Tower Hospital, China (approval No. 2019AE01040) on June 25, 2019.

Routine Histopathological Analysis of the Synovium in Patients with Primary Total Knee Arthroplasty

Although there are numerous studies about routine histopathological analysis during arthroplasty surgeries, most of them showed that new diagnoses have rarely been obtained as a result. The aim of this study was to evaluate the efficacy of routine pathological analyses of synovia resected during primary total knee arthroplasty in patients with osteoarthritis and its relevance in the treatment process. Of the 47 included patients who were followed up prospectively, 26 patients had clinical and histopathological concordant diagnoses and 21 patients had discrepant diagnoses. Oxford knee score and visual analogue score were performed for all the patients. Kallgren-Lawrence score was used for radiological analyses. The Mann-Whitney U test was used to examine the differences between the abnormally distributed variables. Mean age was 65.9 ± 4.3 years (range, 50-89 years) and mean follow-up time was 19 ± 7.8 months (range, 6-39 months). Grade IV gonarthrosis was found to be statistically lower in the discrepant group (p = 0.046). The mean preoperative Oxford knee score was 16.8 ± 2.3 (range, 2-23) and the mean postoperative Oxford knee score was 44.6 ± 1.8 (range, 27-48; p = 0.016). Postoperative Oxford knee scores and VAS were significantly increased in both the concordant and discrepant groups (p = 0.026 and p = 0.035, p = 0.019 and p = 0.039, respectively). Resection and histopathologic analyses of the hypertrophied and inflamed synovium encountered during primary arthroplasty procedure should be performed. This examination not only could provide crucial information that may influence the postoperative follow-up guidelines but also could help us to expand our knowledge and awareness of rare diseases that might yield osteoarthritis. The level of evidence for the study is level II.

Usefulness of inflammatory markers and clinical manifestation for an earlier method to diagnosis surgical site infection after spinal surgery

PURPOSE

To put forward a method for earlier diagnosis of surgical site infection (SSI) after spinal surgery and identify the best cut-offs of the selective signs.

METHODS

Ninety cases were prospectively collected in consecutive patients who underwent spinal surgery. The patients were divided into the SSI group and the normal group. White blood cell (WBC) count, lymphocyte count, serum amyloid A (SAA), procalcitonin (PCT) and C-reactive protein (CRP) were collected pre-operatively and at three andsix days post-operatively. Erythrocyte sedimentation rates (ESR) were acquired pre-operatively and at six days post-operatively. Body temperature (BT) was measured every day during hospitalisation. The conditions of the surgical sites were recorded at three and six days post-operatively. Differences of BT, the conditions of the wound and the values of the inflammatory markers between the two groups were studied. Finally, we used the receiver operating characteristic curve (ROC curve) to determine the best cut-offs of the selected signs.

RESULTS

Of the 90 patients, SSI occurred in seven and five of them reached a definite diagnosis of SSI as their bacterial cultures were positive. Significant differences were found in CRP levels at three and six days post-operatively with a cut-off of > 59.4 mg/L and > 34.9 mg/L, respectively; ESR level at six days post-operatively with a cut-off of > 51.5 mm/h; PCT at three days post-operatively with a cut-off of > 0.11 ng/mL; and BT at three days post-operatively with a cut-off of > 37 °C. Also, examination of the wound is also an important sign of SSI.

CONCLUSION

CRP, ESR and PCT are considered useful markers for earlier diagnosis of SSI. Combining the above markers with BT and the wound condition yields more accurate results.

Stenotrophomonas maltophilia spondylodiscitis following lumbar microdiscectomy mimicking a cotton granuloma: A case report and literature review

Background:

Vertebral osteomyelitis caused by Stenotrophomonas maltophilia is very rare. There are only two cases reported in literature. Here, we present a 48-year-old immunocompetent male who, following a lumbar microdiscectomy, developed postoperative spondylodiscitis due to S. maltophilia that mimicked a cotton granuloma.

Case Report:

Two months ago, a 48-year-old male underwent a lumbar L4-L5 microdiscectomy, he newly presented with the left thigh and leg pain of 4 weeks duration. Laboratory studies revealed a CRP of 26 mg/l, an ESR of 6 mm (1^st h), and total leukocyte count of 7.85 thousand/ul. The MRI T2 images showed a focal hyperintense lesion in the left lateral recesses at the L4-L5 level; the accompanying hypointense-smooth margin resembled a cotton granuloma. At surgery, we found a localized epidural collection of pus; S. maltophilia was isolated from the culture. His symptoms gradually improved, and symptoms fully resolved with 3 months of subsequent antibiotic therapy.

Conclusion:

S. maltophilia causing vertebral osteomyelitis is extremely rare and can sometimes mimic a cotton granuloma. MR diagnosis, surgical decompression, and obtaining cultures are requisite to direct appropriate antibiotic therapy.

Retrospective study to evaluate the clinical significance of a second rise in C-reactive protein level following instrumented spinal fusion surgery

BACKGROUND

This study aimed to identify the incidence and causes of a second rise in C-reactive protein (CRP) levels following spinal instrumentation surgery and to help determine how an abnormal CRP response should be interpreted and managed during postoperative care.

METHODS

The medical records of 948 patients who underwent instrumented spine fusion surgery and met the inclusion criteria were retrospectively reviewed to assess the frequency and causes of a second rise (SR) of CRP. A SR of CRP was defined when the CRP level after postoperative day 7 increased by more than 0.5 mg/dl from that at the previous time-point. The diagnostic cut-off value of CRP elevation for detection of surgical site infection (SSI) was determined. Cut-off values were analyzed using receiver operating characteristic (ROC) curves. Bayes' theorem was used to determine blood test posterior probabilities for SSI-positive cases using cutoff values of re-evaluated CRP levels.

RESULTS

SR of CRP occurred in 107 of the 948 patients. Of the patients with SR of CRP, 38 (35%) patients had developed SSI, 33 (31%) patients had causes other than SSI, and the remaining 36 patients had unidentified causes. Among the patients with SR, excluding those with causes other than SSI, the best diagnostic cut-off value of SR for detection of SSI was 3.04 mg/dl (area under the curve was 0.74). The posterior test probability was 84.4%.

CONCLUSIONS

For patients with SR of CRP, who had no causes other than SSI, an SR value of 3.04 mg/dl correlated with a high probability of developing SSI.

Spontaneous spondylodiscitis: review, incidence, management, and clinical outcome in 44 patients

OBJECTIVESpontaneous spondylodiscitis remains uncommon but is a serious complication of the vertebral column. Risk factors include diabetes, hemodialysis, intravenous drug abuse, and chronic steroid use, and pain is the most common presenting symptom. This study aims to review the literature and report on the incidence, management, and clinical outcome of spontaneous spondylodiscitis in 44 patients.METHODSThis is a prospective study including 44 patients with spontaneous spondylodiscitis managed in the neurosurgery department of Cairo University Hospitals during the period between January 2012 and October 2017. All patients had a full clinical assessment, laboratory tests, radiological studies in the form of MRI with and without contrast, and a postoperative follow-up of up to 12 months.RESULTSTwelve cases underwent conservative treatment in the form of complete bed rest, intravenous antibiotics, and a spinal brace. Ten cases underwent surgical intervention in the form of laminectomy, debridement, and open biopsy. Twenty-two cases underwent laminectomy and surgical stabilization with fusion. There were 15 cases of tuberculous spondylodiscitis, 6 cases of brucellosis, 6 cases of pyogenic infection, and 17 cases in which no organism could be detected.CONCLUSIONSOnce the primary diagnosis is confirmed, early and adequately prolonged antibiotic therapy is recommended for spontaneous spondylodiscitis. Some cases can be successfully treated with conservative treatment alone, whereas surgery may be needed in other cases such as severe destruction of endplates, spinal abscess formation, mechanical instability, neurological deficits, and severe pain that have failed to respond to conservative treatment.

Strategies for the Prevention and Treatment of Surgical Site Infection in the Lumbar Spine

Surgical site infection (SSI) following spine surgery can be devastating for both the patient and the surgeon. It leads to significant morbidity and associated health care costs, from readmissions, reoperations, and subsequent poor clinical outcomes. Complications associated with SSI following spine surgery include pseudarthrosis, neurological deterioration, sepsis, and death. Its management can be very challenging. The diagnosis of SSI involves the interpretation of combined clinical, laboratory, and occasionally radiologic findings. Most infections can be treated with an appropriate course of antibiotics and bracing if required. Surgical intervention is usually reserved for infections resistant to medical management, the need for open biopsy/culture, evolving spinal instability or deformity, and neurologic deficit or deterioration. A thorough knowledge of associated risk factors is required and patients should be stratified for risk preoperatively. The multifaceted approach of risk stratification, early diagnosis and effective treatment, is essential for successful prevention and effective treatment and crucial for a satisfactory outcome.

Impact of MSSA screening on rates of surgical site infection following lumbar spine surgery

PURPOSE

Methicillin-sensitive Staphylococcus aureus (MSSA) carriage may confer a significant risk of surgical site infection (SSI) and is common amongst the UK population. Screening for MSSA is not routinely offered to patients in the UK. Primary aim was to review the impact of introducing a MSSA screening programme, in addition to established Methicillin-resistant Staphylococcus aureus (MRSA) screening, on the incidence of SSIs following lumbar spine surgery.

METHODS

A consecutive group of 1307 patients during 12 months before (phase 1: n = 716) and after (phase 2: n = 591) introduction of the MSSA screening programme were compared. Analysis was restricted to those with inpatient stay greater than 4 days, readmission within 6 weeks and a rising CRP 7 or more days following the procedure. Diagnosis of SSI was based around the CDC guidelines for wound surveillance. Patients were excluded where the primary surgery was to treat infection, or the procedure was percutaneous. Chi-squared test was used to compare the two groups.

RESULTS

Seven hundred and sixteen patients were in phase 1. Rate of infection was 2.65%. Rate of MRSA colonisation was 0%. Five hundred and ninety-one patients were in phase 2. Rate of infection was 1.02%. Rate of MRSA colonisation was 0%, and rate of MSSA colonisation was 26%. Reduction in incidence of SSIs was 62% (p = 0.0409).

CONCLUSION

MSSA colonisation is common, although wound infection following lumbar spinal surgery remains a rare event. A screening programme for MSSA can significantly reduce incidence of SSIs in this patient group. These findings may be applicable to wider elective orthopaedic practice. These slides can be retrieved under Electronic Supplementary Material.

Implementation of an infection prevention bundle and increased physician awareness improves surgical outcomes and reduces costs associated with spine surgery

OBJECTIVE

Previous studies have demonstrated the efficacy of infection prevention protocols in reducing infection rates. This study investigated the effects of the development and implementation of an infection prevention protocol that was augmented by increased physician awareness of spinal fusion surgical site infection (SSI) rates and resultant cost savings.

METHODS

A cohort clinical investigation over a 10-year period was performed at a single tertiary spine care academic institution. Preoperative infection control measures (chlorohexidine gluconate bathing, Staphylococcus aureus nasal screening and decolonization) followed by postoperative infection control measures (surgical dressing care) were implemented. After the implementation of these infection control measures, an awareness intervention was instituted in which all attending and resident neurosurgeons were informed of their individual, independently adjudicated spinal fusion surgery infection rates and rankings among their peers. During the course of these interventions, the overall infection rate was tracked as well as the rates for those neurosurgeons who complied with the preoperative and postoperative infection control measures (protocol group) and those who did not (control group).

RESULTS

With the implementation of postoperative surgical dressing infection control measures and physician awareness, the postoperative spine surgery infection rate decreased by 45% from 3.8% to 2.1% (risk ratio 0.55; 95% CI 0.32–0.93; p = 0.03) for those in the protocol cohort, resulting in an estimated annual cost savings of $291,000. This reduction in infection rate was not observed for neurosurgeons in the control group, although the overall infection rate among all neurosurgeons decreased by 54% from 3.3% to 1.5% (risk ratio 0.46; 95% CI 0.28–0.73; p = 0.0013).

CONCLUSIONS

A novel paradigm for spine surgery infection control combined with physician awareness methods resulted in significantly decreased SSI rates and an associated cost reduction. Thus, information sharing and physician engagement as a supplement to formal infection control measures result in improvements in surgical outcomes and costs.

Management of Postoperative Discitis: A Review of 31 Patients

BACKGROUND

The aim of the study was to retrospectively evaluate the outcome of medical management of postoperative discitis (POD).

MATERIALS AND METHODS

A total of 31 patients treated for POD were included in the study. Clinical, radiological, and laboratory data of all patients were collected and evaluated. All patients were treated initially with bed rest and antibiotic therapy after radiological diagnosis. Surgical management was undertaken after failure of 4 weeks of conservative management. All cases were followed clinically with laboratory and radiological investigations.

RESULTS

Five cases failed to respond to medical management and were treated surgically with debridement and transpedicular fixation. All patients showed clinical recovery till the last follow-up.

CONCLUSION

Early diagnosis and proper management are the keys to successful outcome of postoperative spndylodiscitis. Surgical debridement and fusion are required when conservative treatment fails.

Diagnostics and antibiotic therapy for spondylodiscitis

Purpose. Spondylodiscitis as a rare disease has increased in recent years; there are only a few recommendations regarding the diagnostics and treatment. The objective of this retrospective study was to characterise these patients and identify factors for a favourable healing process - with an emphasis on antibiotic therapy.Methodology. Findings/treatment regimens for all patients with spondylodiscitis treated at a tertiary care hospital in 2012/2013 were recorded. The patients were classified into two groups, depending on the healing process.Results. Fifty-seven patients met the clinical/radiological criteria for spondylodiscitis. The main symptom was massive back pain, combined with a moderate CRP elevation (median 96 mg l^-1), and occasionally fever (39 %). CT-guided aspiration - in addition to blood cultures - improved the detection rate for the causative pathogen from 49 to 82 %. Thirty patients had a favourable clinical course; 25 had an unfavourable clinical course (prolonged clinical course, recurrence, death). Pathogen-specific antibiotic therapy had a decisive effect on the clinical course: initial high-dose intravenous therapy for at least 14 days was associated significantly more often with a favourable clinical course (90 vs 30 % after 24 months, P<0.001). Fourteen days after the start of treatment, marked pain reduction and a CRP reduction of at least 50 % were good prognostic parameters and markers of effective antibiotic therapy.Conclusion. Pathogen detection and establishment of an optimal antibiotic regimen are cornerstones of successful conservative therapy for spondylodiscitis. Targeted initial intravenous therapy for at least 14 days with a bactericidal antibiotic leads to a better clinical course.

Postoperative Changes in Presepsin Level and Values Predictive of Surgical Site Infection After Spinal Surgery: A Single-Center, Prospective Observational Study

STUDY DESIGN

Single-institutional, prospective observational study.

OBJECTIVE

To elucidate the perioperative kinetics of presepsin (PSEP) in patients undergoing spinal surgery, and to evaluate the possibility of PSEP in the early diagnosis of surgical site infection (SSI).

SUMMARY OF BACKGROUND DATA

Early diagnosis of SSI after spinal surgery is important. Although several biomarkers have been used as early indicators of SSI, the specificity of these markers in SSI diagnosis was not high. PSEP was found as a novel diagnostic marker for bacterial sepsis in 2004. However, its kinetics after spinal surgery and its usefulness in early diagnosis of SSI have never been evaluated.

METHODS

A total of 118 patients who underwent elective spinal surgery were enrolled. PSEP was measured before, immediately after, 1 day after, and 1 week after surgery. In patients without postoperative infection, perioperative kinetics of PSEP were analyzed. PSEP levels in patients with postoperative infection were also recorded separately, and their utility in SSI diagnosis was evaluated.

RESULTS

In the 115 patients without postoperative infection, the median PSEP value was 126, 171, 194, and 147 pg/mL before, immediately after, 1 day after, and 1 week after surgery, respectively. Compared with the preoperative value, PSEP was significantly higher immediately after surgery and the next day, and return to the preoperative level 1 week after surgery. The estimated reference value for 95 percentile in patients without postoperative infection was 297 pg/mL 1 week after surgery. In three patients with postoperative infection, higher levels (>300 pg/mL) were observed 1 week after surgery.

CONCLUSION

In patients after spinal surgery without infectious complications, blood levels of PSEP may immediately increase and return to preoperative levels 1 week after surgery. The PSEP value of 300 pg/mL 1 week after surgery might be used as a novel indicator for suspected SSI.

LEVEL OF EVIDENCE

4.

One-stage posterior approaches for treatment of thoracic spinal infection: Transforaminal and costotransversectomy, compared with anterior approach with posterior instrumentation

Treating thoracic infective spondylodiscitis with anterior surgical approaches carry a relatively high risk of perioperative and postoperative complications. Posterior approaches have been reported to result in lower complication rates than anterior procedures, but more evidence is needed to demonstrate the safety and efficacy of 1-stage posterior approaches for treating infectious thoracic spondylodiscitis.Preoperative and postoperative clinical data, of 18 patients who underwent 2 types of 1-stage posterior procedures, costotransversectomy and transforaminal thoracic interbody debridement and fusion and 7 patients who underwent anterior debridement and reconstruction with posterior instrumentation, were retrospectively assessed.The clinical outcomes of patients treated with 1-stage posterior approaches were generally good, with good infection control, back pain relief, kyphotic angle correction, and either partial or solid union for fusion status. Furthermore, they achieved shorter surgical time, fewer postoperative complications, and shorter hospital stay than the patients underwent anterior debridement with posterior instrumentation.The results suggested that treating thoracic spondylodiscitis with a single-stage posterior approach might prevent postoperative complications and avoid respiratory problems associated with anterior approaches. Single-stage posterior approaches would be recommended for thoracic spine infection, especially for patients with medical comorbidities.

Postoperative Kinetics of C-Reactive Protein and Erythrocyte Sediment Rate in One-, Two-, and Multilevel Posterior Spinal Decompressions and Instrumentations

STUDY DESIGN

Prospective study.

OBJECTIVE

To characterize the normal pattern of kinetics of postoperative C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) after decompression, spinal instrumentation, and posterolateral fusion in 1, 2, and more than 2 levels.

METHODS

Blood specimens were obtained from patients who underwent posterior decompression, instrumentation with pedicular screws, and posterolateral fusion from June 2009 to January 2011. CRP and ESR levels were measured on the day before surgery and on postoperative days 1, 3, 7, 11, 14, 28, and 42.

RESULTS

Mean CRP levels peaked on the third day postoperatively in all groups. By day 7 postoperatively, it had dropped rapidly. At the 14th and 28th postoperative days, decreases to normal CRP levels were found in 16% and 80% of all patients, respectively. The pattern of decline in CRP was similar among groups. Values of ESR increased and peaked between the third and seventh postoperative days. ESR values gradually decreased. At the 42 day postoperatively, ESR level still remain above normal values in all groups.

CONCLUSIONS

We compared conventional operation groups of 1-, 2-, and more than 2-level posterior instrumentation and found no statistically significant differences in the peak of CRP level, the ESR value, and the pattern of decline. CRP levels of 80% of the patients returned to normal within 4 weeks.

Multidisciplinary management of spontaneous spinal infections: is there a correlation between timing, type of treatment and outcome?

BACKGROUND

Spontaneous spinal infections (SSIs) represent a rare and serious pathological entity. We tried to study a correlation between type of treatment, timing of treatment and clinical outcome through a multivariate analysis of an observational cohort study with the aim to define what is the optimal clinico-therapeutic management.

METHODS

We performed a retrospective observational cohort study on all consecutive patients observed in our Institute in a period of 13 years; from 2001 to 2014 we enrolled 50 consecutive patients with symptomatic spontaneous spinal infections (no previous surgery or recent infection in other site), confirmed with diagnostic imaging. The inclusion parameters were: diagnostic imaging, signs and symptoms positive for SSI, no history of recent infection or surgery. Of each parameter analyzed, we calculated mean and standard deviation and when necessary correlation (ρ), covariance (σ) and relation coefficient between type of treatment, timing of treatment and clinical outcome.

RESULTS

Our results suggest that an increase of one day from the onset of symptoms and the start of therapy leads to an increase in the Oswestry Disability Index Scale both at 6 months than at 1 year, with a statistical relevance, so our experience shows a statistically significant correlation and a positive co-variance between timing and outcome at 6 months and 1 year.

CONCLUSIONS

SSI are rare, very difficult to diagnose and represent a significant clinical problem. If not properly managed, they may lead to significant impact in the quality of life. The most relevant problem is not the treatment, conservative or surgical, but early diagnosis, so a careful physical, laboratory and imaging examination is fundamental, with an important help provided by isolation of the pathogen and histology. In our experience early diagnosis has a fundamental role. In the light of this, current treatment protocols may require a prompt and multidisciplinary management including infectivologists, neuroradiologists and spine surgeons.

Lymphopenia and Elevated Blood C-Reactive Protein Levels at Four Days Postoperatively Are Useful Markers for Early Detection of Surgical Site Infection Following Posterior Lumbar Instrumentation Surgery

STUDY DESIGN

Case-control study.

PURPOSE

To identify the characteristics of candidate indexes for early detection of surgical site infection (SSI).

OVERVIEW OF LITERATURE

SSI is a serious complication of spinal instrumentation surgery. Early diagnosis and treatment are crucial for the welfare of the patient postoperation.

METHODS

We retrospectively reviewed laboratory data of patients who underwent posterior lumbar instrumentation surgery for degenerative spine disease. The sensitivity and specificity of six laboratory markers for early detection of SSI were calculated: greater elevation of the white blood cell count at day 7 than at day 4 postoperatively, greater elevation of the C-reactive protein (CRP) level at day 7 than at day 4 postoperatively, a CRP level of >10 mg/dL at 4 days postoperatively, neutrophil percentage of >75% at 4 days postoperatively, a lymphocyte percentage of <10% at 4 days postoperatively, and a lymphocyte count of <1,000/µL at 4 days postoperatively. Statistical analysis was via Fisher's exact test and a p-value of <0.05 was considered significant.

RESULTS

In total, 85 patients were enrolled. Of these, five patients developed deep SSI. The sensitivity and specificity of each index were as follows: index 1, 20.0% and 77.5%; index 2, 20.0% and 83.8%; index 3, 40.0% and 97.5%; index 4, 40.0% and 86.3%; index 5, 0% and 96.3%; and index 6, 80.0% and 80.0%. A significant difference was noted for indexes 3 and 6.

CONCLUSIONS

A CRP level of >10 mg/dL at 4 days postoperatively would be useful for definitive diagnosis of SSI, and a lymphocyte count of <1,000/µL at 4 days postoperatively would be a useful screening test for SSI. Although laboratory markers for early detection of SSI have been frequently reported, we believe that it is important to understand the characteristics of each index for a precise diagnosis.

A threshold for concern? C-reactive protein levels following operatively managed neck of femur fractures can detect infectious complications with a simple formula

INTRODUCTION

C-reactive protein (CRP) rises in response to multiple stimuli, including surgical procedures and infections. Deviations from the predicted CRP response to a given procedure may be an early indication of a postoperative complication.

METHODS

Three hundred and fifty-four patients with an operatively managed neck of femur fracture admitted over a 1-year period to an NHS Hospital Trust were included. CRP values collected during the postoperative period were retrospectively examined, and objective evidence of postoperative complications was sought. Data analysis explored daily CRP thresholds that maximised sensitivity and specificity for the detection of patients with a postoperative complication.

RESULTS

From the 5th to the 30th postoperative day, a CRP value in excess of the threshold defined by the formula 500/d (where d represents the number of postoperative days) retrospectively detected patients with a postoperative complication with a sensitivity of 0.97 and specificity of 0.82. Patients with a CRP value above the 500/d threshold during this period had a significantly increased 30-day mortality (10.0% vs. 3.9%, RR=2.74, p=0.03).

CONCLUSION

Following operatively managed neck of femur fractures, a CRP value in excess of the threshold defined by the formula 500/d may indicate the presence of a postoperative complication and defines a group with increased mortality. In this context, a prompt wound review and septic screen could promote the early detection and management of infectious postoperative complications.

Efficacy of Antibiotics Sprayed into Surgical Site for Prevention of the Contamination in the Spinal Surgery

Study Design

Retrospective study.

Purpose

To evaluate the effect of intraoperative wound application of vancomycin on preventing surgical wound contamination during instrumented lumbar spinal surgery.

Overview of Literature

Postoperative infection is the one of the most devastating complications of lumbar surgery. There are a few reports showing the benefits of intraoperative wound application of vancomycin during spinal surgery. However, there is no report about the effectiveness of local vancomycin instillation in prevention of surgical wound contamination.

Methods

Eighty-six patients underwent instrumented lumbar spinal surgery. Mean patient age was 65.19 years (range, 23-83 years). There were 67 females and 19 males. During surgery, vancomycin powder was applied into the surgical site before closure in 43 patients (antibiotic group) and vancomycin powder was not applied into the surgical site before closure in 43 patients (control group). The tip of the surgical drain was cultured to evaluate surgical wound contamination. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured on the first, third, seventh, and fourteenth day after the operation.

Results

We found two patients with a positive culture from the tip of surgical drains in the antibiotic group, and one patient with a positive culture from the tip of the surgical drain in the control group. Postoperative ESR and CRP levels did not show significant differences between the two groups. On the third postoperative day, ESR in patients of the antibiotic group was more significantly decreased than that in patients of the control group, while CRP level did not show a significant difference between the two groups.

Conclusions

There was no evidence to suggest that intraoperative vancomycin application is effective in decreasing the risk of postoperative wound infection after instrumented posterior lumbar fusion surgery.

Management of wound infection after lumbar arthrodesis maintaining the instrumentation

<sec><title>OBJECTIVE:</title><p> To determinate whether a surgical protocol with immediate extensive debridement, closed irrigation system and antibiotic therapy would be effective to achieve healing of deep wound infection without removing the instrumentation.</p></sec><sec><title>METHODS:</title><p> Prospective cohort study with 19 patients presenting degenerative spinal stenosis or degenerative spondylolisthesis, who developed infection after posterior lumbar arthrodesis. The diagnosis was confirmed by a microbial culture from subfascial lumbar fluid and/or blood. Patients were treated with a protocol of wound exploration, extensive flushing and debridement, placement of a closed irrigation system that was maintained for five days and intravenous antibiotics. The instrumentation system was not removed.</p></sec><sec><title>RESULTS:</title><p> Mean age was 59.31 (±13.17) years old and most patients were female (94.7%; 18/19). The mean period for the identification of the infection was 2 weeks and 57.9% underwent a single wound exploration. White blood count, erythrocyte sedimentation rate and C-reactive protein showed a significant decrease post-treatment when compared to pre-treatment values. A significant reduction of erythrocyte sedimentation rate and C-reactive protein was also observed at the final evaluation. No laboratory test was useful to predict the need for more than one debridement.</p></sec><sec><title>CONCLUSION:</title><p> Patients with wound infection after instrumentation can be treated without removal of the instrumentation through wound exploration, extensive flushing, debridement of necrotic tissue, closed irrigation system during 5 days and proper antibiotic therapy. The blood tests were not useful to predict surgical re-interventions.</p></sec>

Postoperative abnormal response of C-reactive protein as an indicator for infectious complications after oral oncologic surgery with primary reconstruction

Background

C-reactive protein (CRP) screening has been reported to be reliable for detection of infectious complications. Postoperative abnormal response of CRP can predict wound infection in colorectal surgery. This study aimed to determine the efficacy of CRP monitoring to detect infectious complications in oral oncologic surgery.

Methods

One hundred patients who underwent oral cancer resection with primary reconstruction were enrolled. Postoperative kinetics of CRP were classified into a normal or abnormal response.

Results

A normal CRP response after surgery was observed in 61 patients and an abnormal response was observed in 39. There were postoperative infectious complications in 21 patients, with surgical site infections in 13 patients (early onset in six and late onset in seven). Non-wound infections were found in nine patients. Sensitivity, specificity, the positive predictive value, and the negative predictive value for abnormal CRP response as a predictor for early infectious complications were 100%, 70.1%, 35.9%, and 100%, respectively.

Conclusion

Postoperative serial CRP screening is a useful test as an indicator of infectious complications in oral oncologic surgery. Normal CRP responses can rule out almost all early infectious complications.

What is new in the diagnosis and prevention of spine surgical site infections

BACKGROUND CONTEXT

Surgical site infection (SSI) after spinal surgery can result in several serious secondary complications, such as pseudoarthrosis, neurological injury, paralysis, sepsis, and death. There is an increasing body of literature on risk factors, diagnosis, and specific intraoperative interventions, including attention to sterility of instrumentation, application of minimally invasive fusion techniques, intraoperative irrigation, and application of topical antibiotics, that hold the most promise for reduction of SSI.

PURPOSE

The purpose of this review is to identify and summarize the recent literature on the incidence, risk factors, diagnosis, prevention, and treatment of SSIs after adult spine surgery.

STUDY DESIGN

The study design included systematic review and literature synthesis.

METHODS

For the systematic reviews, a search was performed in Medline and Scopus using keywords derived from a preliminary review of the literature and Medline MeSH terms. These studies were then manually filtered to meet the study criteria outlined in each section. Studies were excluded via predetermined criteria, and the majority of articles reviewed were excluded.

RESULTS

There are a number of patient- and procedure-specific risk factors for SSI. Surgical site infection appears to have significant implications from the patients' perspective on outcome of care. Diagnosis of SSI appears to rely primarily on clinical factors, while laboratory values such as C-reactive protein are not universally sensitive. Similarly, novel methods of perioperative infection prophylaxis such as local antibiotic administration appear to be modestly effective.

CONCLUSIONS

Surgical site infections are a common multifactorial problem after spine surgery. There is compelling evidence that improved risk stratification, detection, and prevention will reduce SSIs.

Surgical site infections following spine surgery: eliminating the controversies in the diagnosis

Surgical site infection (SSI) following spine surgery is a dreaded complication with significant morbidity and economic burden. SSIs following spine surgery can be superficial, characterized by obvious wound drainage or deep-seated with a healed wound. Staphylococcus aureus remains the principal causal agent. There are certain pre-operative risk factors that increase the risk of SSI, mainly diabetes, smoking, steroids, and peri-operative transfusions. Additionally, intra-operative risk factors include surgical invasiveness, type of fusion, implant use, and traditional instead of minimally invasive approach. A high level of suspicion is crucial to attaining an early definitive diagnosis and initiating appropriate management. The most common presenting symptom is back pain, usually manifesting 2–4 weeks and up to 3 months after a spinal procedure. Scheduling a follow-up visit between weeks 2 and 4 after surgery is therefore necessary for early detection. Inflammatory markers are important diagnostic tools, and comparing pre-operative with post-operative levels should be done when suspecting SSIs following spine surgery. Particularly, serum amyloid A is a novel inflammatory marker that can expedite the diagnosis of SSIs. Magnetic resonance imaging remains the diagnostic modality of choice when suspecting a SSI following spine surgery. While 18F-fluorodeoxyglucose-positron emission tomography is not widely used, it may be useful in challenging cases. Despite their low yield, blood cultures should be collected before initiating antibiotic therapy. Samples from wound drainage should be sent for Gram stain and cultures. When there is a high clinical suspicion of SSI and in the absence of superficial wound drainage, computed tomography-guided aspiration of paraspinal collections is warranted. Unless the patient is hemodynamically compromised, antibiotics should be deferred until proper specimens for culture are secured.

Surgical site infection in spinal surgery: a comparative study between 2-octyl-cyanoacrylate and staples for wound closure

BACKGROUND

Surgical site infection (SSI) after spinal surgery is a devastating complication. Various methods of skin closure are used in spinal surgery, but the optimal skin-closure method remains unclear. A recent report recommended against the use of metal staples for skin closure in orthopedic surgery. 2-Octyl-cyanoacrylate (Dermabond; Ethicon, NJ, USA) has been widely applied for wound closure in various surgeries. In this cohort study, we assessed the rate of SSI in spinal surgery using metal staples and 2-octyl-cyanoacrylate for wound closure.

METHODS

This study enrolled 609 consecutive patients undergoing spinal surgery in our hospital. From April 2007 to March 2010 surgical wounds were closed with metal staples (group 1, n = 294). From April 2010 to February 2012 skin closure was performed using 2-octyl-cyanoacrylate (group 2, n = 315). We assessed the rate of SSI using these two different methods of wound closure. Prospective study of the time and cost evaluation of wound closure was performed between two groups.

RESULTS

Patients in the 2-octyl-cyanoacrylate group had more risk factors for SSI than those in the metal-staple group. Nonetheless, eight patients in the metal-staple group compared with none in the 2-octyl-cyanoacrylate group acquired SSIs (p < 0.01). The closure of the wound in length of 10 cm with 2-octyl-cyanoacrylate could save 28 s and $13.5.

CONCLUSIONS

This study reveals that in spinal surgery, wound closure using 2-octyl-cyanoacrylate was associated with a lower rate of SSI than wound closure with staples. Moreover, the use of 2-octyl-cyanoacrylate has a more time saving effect and cost-effectiveness than the use of staples in wound closure of 10 cm in length.

Admission inflammatory markers and isolation of a causative organism in patients with spontaneous spinal infection

INTRODUCTION

The purpose of this study was to investigate the significance of the inflammatory markers on admission in the isolation of a causative pathogen in patients with spinal infection. Spinal infection is treated frequently at spinal units and can encompass a broad range of clinical entities. Its diagnosis is often delayed because of the difficulty of identifying the responsible pathogen.

METHODS

Patients with spinal infection treated in our institution over a period of eight years were identified and their notes studied retrospectively. Admission C-reactive protein (CRP), white cell count (WCC) as well as co-morbidities and mode of pathogen identification were recorded. Overall, 96 patients were included in the study.

RESULTS

The CRP levels on admission were correlated significantly with the overall potential for isolation of a pathogen (p<0.0001) and positive biopsy cultures (p=0.0016). Admission WCC levels were associated significantly with the overall potential for isolation of a pathogen (p=0.0003) and positive biopsy cultures (p=0.0023). Both CRP and WCC levels were significantly negatively correlated with the duration of the preceding symptoms (p=0.0003 and p<0.0001 respectively). Delay in presentation was significantly negatively correlated with organism isolation (p=0.0001). Multivariate analyses identified the delay in presentation as the strongest independent variable for organism isolation (p=0.014) in cases of spontaneous spinal infection when compared with the admission CRP level (p=0.031) and WCC (p=0.056).

CONCLUSIONS

In spontaneous spinal infection, delay in presentation is the strongest independent variable for organism isolation. High inflammatory marker levels on admission are a useful prognostic marker for the overall potential of isolating a causative organism either by blood cultures or by biopsy in patients with negative blood cultures. Furthermore, the admission inflammatory marker levels allow for treating surgeons to counsel their patients of the likelihood of achieving a positive microbiological yield from biopsy.

Elevated serum lactoferrin and neopterin are associated with postoperative infectious complications in patients with acute traumatic spinal cord injury

INTRODUCTION

Several studies have shown that lactoferrin (LF) and neopterin (NT) are correlated with infection. The aim of this study is to determine whether serum levels of LF and NT are associated with postoperative infectious complications in patients with acute traumatic spinal cord injury.

MATERIAL AND METHODS

A total of 268 patients with acute traumatic spinal cord injury who underwent spinal surgery were enrolled in this study. Serum levels of LF, NT, and C-reactive protein (CRP), in addition to white blood cell count (WBC) and erythrocyte sedimentation rate (ESR), were measured preoperatively and 24 h postoperatively.

RESULTS

In total, 22 of 268 patients (8.2%) developed postoperative infectious complications. The levels of serum LF, NT, and CRP were significantly higher in the infected patients than in the non-infected patients. No significant differences were observed in postoperative WBC count and ESR between the two groups. Multivariate logistic regression revealed that LF (OR: 1.004 (1.002-1.007)), NT (OR: 1.137 (1.054-1.227)), and CRP (OR: 1.023 (1.002-1.044)) were significantly associated with the presence of postoperative infectious complications. The area under receiver operating characteristic curves for LF, NT, and CRP was 0.709, 0.779, and 0.629, respectively.

CONCLUSIONS

Elevated serum concentrations of LF and NT are associated with early infection after surgery. Compared to CRP, elevated levels of LF and NT are better indicators for predicting postoperative infectious complications in patients with acute traumatic spinal cord injury.

Infection with spinal instrumentation: Review of pathogenesis, diagnosis, prevention, and management

Background:

Instrumentation has become an integral component in the management of various spinal pathologies. The rate of infection varies from 2% to 20% of all instrumented spinal procedures. Every occurrence produces patient morbidity, which may adversely affect long-term outcome and increases health care costs.

Methods:

A comprehensive review of the literature from 1990 to 2012 was performed utilizing PubMed and several key words: Infection, spine, instrumentation, implant, management, and biofilms. Articles that provided a current review of the pathogenesis, diagnosis, prevention, and management of instrumented spinal infections over the years were reviewed.

Results:

There are multiple risk factors for postoperative spinal infections. Infections in the setting of instrumentation are more difficult to diagnose and treat due to biofilm. Infections may be early or delayed. C Reactive Protein (CRP) and Magnetic Resonance Imaging (MRI) are important diagnostic tools. Optimal results are obtained with surgical debridement followed by parenteral antibiotics. Removal or replacement of hardware should be considered in delayed infections.

Conclusions:

An improved understanding of the role of biofilm and the development of newer spinal implants has provided insight in the pathogenesis and management of infected spinal implants. This literature review highlights the mechanism, pathogenesis, prevention, and management of infection after spinal instrumentation. It is important to accurately identify and treat postoperative spinal infections. The treatment is often multimodal and prolonged.