High Rates of Occult Infection After Shoulder Fracture Fixation: Considerations for Conversion Shoulder Arthroplasty

High Rate of Undetected Infections in Failed Osteosynthesis of Pertrochanteric Fractures

OBJECTIVE

The objective of this study was to assess the incidence of infection in patients with cutout after proximal femur fracture (PFF) osteosynthesis.

METHODS

DESIGN

Retrospective cohort study.

SETTING

Third-level trauma center.

PATIENT SELECTION CRITERIA

Patients presenting with a cutout following PFF (OTA/AO 31A) osteosynthesis, between January 2007 and December 2020.

OUTCOME MEASUREMENTS AND COMPARISONS

The primary outcome was infection according to the European Bone and Joint Infection Society criteria.

RESULTS

Sixty-seven patients presenting with a cutout were included, with mean age of 83.3 years (range 63-96), and 51 (76.1%) were women. Of all cases, 16 (24.7%) presented a concomitant infection. The presence of concomitant infection was suspected preoperatively in only 3 of the cases. A subgroup analysis was performed between the cases with infection and those without infection, the groups being comparable in terms of demographic data and postoperative radiological criteria. Patients with underlying infection had a higher rate of surgical wound complication (56.3% vs. 22%, P = 0.014) and higher rates of leukocytosis (11.560 vs. 7.890, P = 0.023).

CONCLUSION

Faced with a cutout after osteosynthesis of a PFF, underlying infection should be considered as a possible etiological factor.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Implant survival of total elbow arthroplasty: analysis of 514 cases from the Dutch Arthroplasty Registry

The aim of this study is to report the implant survival and factors associated with revision of total elbow arthroplasty (TEA) using data from the Dutch national registry. All TEAs recorded in the Dutch national registry between 2014 and 2020 were included. The Kaplan-Meier method was used for survival analysis, and a logistic regression model was used to assess the factors associated with revision. A total of 514 TEAs were included, of which 35 were revised. The five-year implant survival was 91%. Male sex, a higher BMI, and previous surgery to the same elbow showed a statistically significant association with revision (p < 0.036). Of the 35 revised implants, ten (29%) underwent a second revision. This study reports a five-year implant survival of TEA of 91%. Patient factors associated with revision are defined and can be used to optimize informed consent and shared decision-making. There was a high rate of secondary revisions.

Conversion total hip arthroplasty following proximal femur fracture: A retrospective analysis

BACKGROUND

The incidence of conversion total hip arthroplasty (cTHA) following reduction and fixation for proximal femur fractures will increase in parallel to the aging population worldwide.

OBJECTIVE

The goal of this study is to report the frequency of bacterial detection and the outcome of cTHA at the authors' institution and to analyze preoperative factors that correlate with higher rates of bacterial growth and septic revision.

METHODS

48 patients who had been converted to THA after osteosynthesis of a proximal femur fracture either by a one- or two-stage procedure were included. Septic failure rate and the frequency of bacterial detection at the time of fixation device removal were calculated. The influence of different preoperative factors was examined by the odds ratio. A receiver operating characteristic curve of c-reactive protein (CRP) for detection of bacterial growth at the time of fixation device removal was calculated.

RESULTS

18.8% patients showed positive bacterial cultures, with Staph. epidermidis being the most frequent pathogen (33.3%). Septic failure after cTHA occurred in 4.2%. Fixation with cephalomedullary nails and complications with the internal fixation showed higher odds for bacterial growth at time of cTHA. CRP for predicting bacterial growth had an area under the curve of 0.661. Implant survival was worse when temporary spacers were used.

CONCLUSION

Bacterial detection rate at the time of cTHA is high, whereas septic failure rates are low. Isolated evaluation of inflammatory blood markers without other diagnostic modalities for infection is not decisive and does not justify a two-stage approach with implantation of a temporary spacer.

Better diagnostic value of tissue cultures obtained during mini-open and arthroscopic procedures compared with sterile punctures to identify periprosthetic shoulder infections: a retrospective cohort study

BACKGROUND

This study aimed to determine the sensitivity and specificity of sterile shoulder needle aspiration and cultures obtained during arthroscopic and mini-open procedures for detecting periprosthetic shoulder infections using tissue cultures from revision surgery as the gold standard.

METHODS

All shoulder arthroplasty patients who underwent a synovial fluid puncture between August 2012 and February 2018 were selected. In addition, arthroplasty patients with cultures obtained during arthroscopic or mini-open procedures between May 2014 and May 2021 were selected. When sterile punctures or biopsy procedures were followed by revision surgery with collection of 6 tissue cultures, patients were included in the study and efficacy measures were calculated.

RESULTS

Fifty-six patients were included in this study (with 57 punctures) and underwent analysis of puncture results after exclusions. Positive puncture results were found for Cutibacterium acnes, Staphylococcus aureus, Staphylococcus hominis, Actinomyces neuii, and Proteus mirabilis. These puncture cultures showed a sensitivity of 20.0% and specificity of 90.6%. From May 2014 to May 2021, 51 biopsy procedures were performed (15 arthroscopic and 36 mini-open); 37 biopsy procedures were included in this study (12 arthroscopic and 25 mini-open) for analysis after exclusions. Positive culture results were found for C acnes, Staphylococcus epidermidis, Staphylococcus saccharolyticus, and Streptococcus species. Arthroscopic biopsy cultures showed a sensitivity of 60.0% and specificity of 85.7%. For the mini-open biopsy cultures, the sensitivity and specificity were 66.7% and 85.7%, respectively.

CONCLUSIONS

Sterile punctures for culture have a low sensitivity and a high specificity for diagnosing periprosthetic shoulder infections. Tissue cultures obtained during mini-open and arthroscopic procedures have a higher sensitivity for detecting periprosthetic shoulder infections.

High rate of unexpected positive cultures in presumed aseptic revision of stiff shoulders after proximal humerus osteosynthesis

BACKGROUND

The aim of this study was to investigate the prevalence of positive microbiology samples after osteosynthesis of proximal humerus fractures at the time of revision surgery and evaluate clinical characteristics of patients with positive culture results.

METHODS

All patients, who underwent revision surgery after locked platting, medullary nailing or screw osteosynthesis of proximal humeral fractures between April 2013 and July 2018 were retrospectively evaluated. Patients with acute postoperative infections, those with apparent clinical signs of infection and those with ≤1 tissue or only sonication sample obtained at the time of implant removal were excluded. Positive culture results of revision surgery and its correlation with postoperative shoulder stiffness was analyzed in patients with an interval of ≥6 months between the index osteosynthesis and revision surgery.

RESULTS

Intraoperatively obtained cultures were positive in 31 patients (50%). Cutibacterium acnes was the most commonly isolated microorganism, observed in 21 patients (67.7%), followed by coagulase negative staphylococci in 12 patients (38.7%). There were significantly more stiff patients in the culture positive group compared to the culture-negative group (19/21, 91% vs. 15/26, 58%, p = 0.02). Furthermore, 11 of 12 (91.7%) patients with growth of the same microorganism in at least two samples had a stiff shoulder compared to 23 of 35 (65.7%) patients with only one positive culture or negative culture results (p = 0.14).

CONCLUSION

Infection must always be considered as a possibility in the setting of revision surgery after proximal humerus osteosynthesis, especially in patients with postoperative stiffness.

Propionibacterium acnes Infection in Disc Material and Different Antibiotic Susceptibility in Patients With Lumbar Disc Herniation

BACKGROUND

Low back pain is an important, worldwide clinical problem from which human populations are suffering. It has been suggested that Propionibacterium acnes is associated with low back pain. The objective of this clinical study is to evaluate the P. acnes infection in the disc material and antibiotic susceptibility in patients with disc herniation.

METHODS

A total of 120 patients with disc herniation surgery were enrolled in the study. The samples were excited during discectomy and then cultured in both anaerobic and aerobic incubations. Minimum inhibitory concentration (MIC) was performed for determination of antibiotic susceptibility.

RESULTS

Of 120 samples, 60 (50%) samples were positive for microorganisms. Disc herniation was at the level of L4-L5 in 63 cases and L5-S1 in 57 cases.

CONCLUSIONS

According to the results and presence of P. acnes in more than 35% of the cultured samples, the presence of P. acnes in lumbar disc herniation is a suspected element leading to this condition. After analysis of the antibiotics, the lowest MIC value was identified for amoxicillin, ciprofloxacin, erythromycin, rifampicin, tetracycline, vancomycin; the moderate MIC value was for fusidic acid; and the highest MIC value was for gentamicin and trimethoprim.

The distribution of infection with Propionibacterium acnes is equal in patients with cervical and lumbar disc herniation

BACKGROUND

Cervical and back pains are important clinical problems affecting human populations globally. It is suggested that Propionibacterium acnes (P. acnes) is associated with disc herniation. The aim of this study is to evaluate the distribution of P. acnes infection in the cervical and lumbar disc material obtained from patients with disc herniation.

METHODS AND MATERIAL

A total of 145 patients with mean age of 45.21 ± 11.24 years who underwent micro-discectomy in cervical and lumbar regions were enrolled into the study. The samples were excited during the operation and then cultured in the anaerobic incubations. The cultured P. acnes were detected by 16S rRNA-based polymerase chain reaction.

RESULTS

In this study, 145 patients including 25 cases with cervical and 120 cases with lumbar disc herniation were enrolled to the study. There was no significant difference in the age of male and female patients (p = 0.123). P. acnes infection was detected in nine patients (36%) with cervical disc herniation and 46 patients (38.3%) with lumbar disc herniation and no significant differences were reported in P. acnes presence according to the disc regions (p = 0.508.). Moreover, there was a significant difference in the presence of P. acnes infection according to the level of lumbar disc herniation (p = 0.028).

CONCLUSION

According to the results, the presence of P. acnes is equal in patients with cervical and lumbar disc herniation. There was a significant difference in the distribution of P. acnes infection according to level of lumbar disc herniation.

LEVEL OF EVIDENCE

II.