Incidence and risk factors for acute infection after proximal humeral fractures: a multicenter study

Analysis of the associated factors in postoperative wound infection following open reduction and internal fixation for elbow fracture

Postoperative wound infections (PWIs) following open reduction and internal fixation (ORIF) for elbow fractures can significantly affect patient outcomes. Identifying associated risk factors is crucial for improving clinical practices and patient care. A retrospective analysis (June 2020-June 2023) at our institution involved 90 patients who underwent elbow ORIF. Thirty patients developed PWIs (case group), compared to 60 who did not (control group). Variables like anaemia, operation duration, hospital stay, blood loss, body mass index (BMI), age, hypoalbuminemia, smoking status, diabetes mellitus and open fractures were examined. Univariate and multivariate analyses determined the impact of these variables on PWI incidence, with statistical significance set at p < 0.05. The main pathogens identified were Escherichia coli among Gram-negative bacteria (59.46%) and Staphylococcus aureus among Gram-positive bacteria (40.54%). In the univariate analysis, hypoalbuminemia, anaemia, and lifestyle factors such as smoking showed higher prevalence in patients with PWIs. However, age and length of hospital stay did not significantly influence infection rates. The multivariate analysis further elucidated that anaemia, smoking, diabetes mellitus and open fractures were independent, significant predictors of PWIs. These findings highlight the complexity of factors influencing infection risk post-ORIF, underscoring the importance of both individual health conditions and surgical complications in patient outcomes. Anaemia, smoking, diabetes mellitus and open fractures significantly increase the risk of PWI after elbow ORIF. Early identification and management of these risk factors are imperative to reduce infection rates and improve postoperative recovery.

Risk factors for surgical site infection after closed proximal humerus fractures

Proximal humerus fractures are common in clinical practice, and there are relatively a few studies on postoperative incision infections of such fractures. The purpose of this study was to explore the risk factors for surgical site infection (SSI) after internal fixation in patients with closed proximal humerus fractures. Patients with closed proximal humerus fractures who underwent surgery from January 2016 to January 2022 were retrospectively analysed. Cases with superficial or deep infections within 3 months after surgery were in the infection group and the remaining cases were in the non-infection group. The types of pathogenic bacteria in the infection group were analysed. The potential risk factors for SSI in all patients were recorded: (1) patient-related factors: gender, age, body mass index (BMI), smoking, comorbidities; (2) trauma-related factors: mechanism of injury, Injury Severity Score, visual analogue scale, fracture type, soft tissue condition and combined dislocation; (3) laboratory-related indexes: haemoglobin, albumin; (4) surgery-related factors: time from injury to surgery, American Society of Anesthesiologists anaesthesia classification, surgical time, fixation mode, intraoperative blood loss, suture method, bone graft and postoperative drainage. The risk factors for the occurrence of SSI were analysed using univariate analysis and multivariate logistic regression. The incidence of SSI was 15.7%. The most common bacterium in the infection group was Staphylococcus aureus. High BMI (p = 0.033), smoking (p = 0.030), an increase in mean time from injury to definitive surgery (p = 0.013), and prolonged surgical time (p = 0.044) were independent risk factors for the development of SSI after closed proximal humeral fractures. In patients with closed proximal humerus fractures, weight loss, perioperative smoking cessation, avoidance of delayed surgery, and shorter surgical time may be beneficial in reducing the incidence of SSI.

The Translated Proximal Humerus Fracture: A Comparison of Operative and Nonoperative Management

OBJECTIVES

To report on the long-term outcomes of the management of translated proximal humerus fractures.

DESIGN

A prospective cohort study was conducted from January 2010 to December 2018.

SETTING

Academic Level 1 trauma center.

PARTICIPANTS/PATIENTS

A total of 108 patients with a proximal humerus fracture with ≥100% translation, defined as no cortical bony contact between the shaft and humeral head fragments, were included.

INTERVENTION

Patients were managed nonoperatively with sling immobilization or with operative management as determined by the treating surgeon.

MAIN OUTCOME MEASURES

Outcome measures were the Oxford Shoulder Score, EQ-5D-5L, return to work, and radiological outcomes. Complications recorded included further surgery, loss of position/fixation, nonunion/malunion, and avascular necrosis.

RESULTS

Of the 108 patients, 76 underwent operative intervention and 32 were managed nonoperatively. The mean (SD) age in the operative group was 54.3 (±20.2) years and in the nonoperative group was 73.3 (±15.3) years ( P < 0.001). There was no association between Oxford Shoulder Score and management options (mean 38.5 [±9.5] operative versus mean 41.3 [±8.5] nonoperative, P = 0.48). Operative management was associated with improved health status outcomes; EQ-5D utility score adjusted mean difference was 0.16 (95% CI, 0.04-0.27; P = 0.008); EQ-5D VAS adjusted mean difference was 19.2 (95% CI, 5.2-33.2; P = 0.008). Operative management was associated with a lower odds of nonunion (adjusted OR 0.30; 95% CI, 0.09-0.97; P = 0.04), malunion (adjusted OR 0.14; 95% CI, 0.04-0.51; P = 0.003), and complications (adjusted OR 0.07; 95% CI, 0.02-0.32; P = 0.001).

CONCLUSION

Translated proximal humerus fractures with ≥100% displacement demonstrate improved health status and radiological outcomes after surgical fixation.

LEVEL OF EVIDENCE

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

The POSI study: gender differences in 94 cases of postoperative shoulder surgery infection: results of a 7-year retrospective multicenter study

BACKGROUND

Contrary to lower limb infection, POstoperative Shoulder surgery Infection (POSI) often involves Cutibacterium acnes. Our aim was to describe patient characteristics and pathogens retrieved in POSI to guide initial empiric antibiotic selection with suspected infection during revision. We also compared microorganisms in infection following trauma, arthroplasty (AP), and arthroscopy (AS).

METHODS

A multicenter retrospective study from 2010 to 2016 reviewed laboratory databases and medical records to identify patients with a previous shoulder surgery and a confirmed shoulder infection. The following procedures were included: AP, AS, fracture fixation (FF), and another open surgery (OS). A confirmed shoulder infection was defined as 2 positive cultures or more of the same microorganism, or clear clinical infection with 1 positive culture or more.

RESULTS

Among the 5 hospitals and 28 surgeons involved, 94 POSI cases were identified. Mean age was 59 years at index surgery (range: 22-91) with a majority of men (n = 70, 74%). Among POSI cases, AP was the most common index surgery (n = 41), followed by FF (n = 27), AS (n = 16), and OS (n = 10). The median time between index surgery and the first positive sample was 5 months and the mean was 23 months (minimum 6 days to maximum 27 years), illustrating a positively skewed distribution. Cutibacterium spp were identified in 64 patients (68%), including 59 C acnes patients (63%), which was the most frequent germ in all 4 surgical groups. In 86% of cases, C acnes was identified at the first revision. The other 2 most common germs were Staphylococcus epidermidis and Staphylococcus aureus, with 29% and 17%, respectively. Polymicrobial infection was present in 30% of patients. Gender analysis revealed that C acnes was twice as frequent in men (male = 52 of 70, female = 7 of 24; P < .001). S epidermidis was more prevalent in women (n = 11; 46%) compared with men (n = 16; 21%) (P = .032). C acnes infection was most frequent in arthroscopic surgery (n = 14; 70%, P = .049). S epidermidis was 3 times more prevalent in chronic than in acute cases.

CONCLUSION

Empiric antimicrobial therapy following POSI, while waiting for culture results, should cover C acnes, S epidermidis, and S aureus. There is a significant gender difference regarding POSI culture results. C acnes is more frequent in men, but should still be covered in women as it was found in 29% of cases.

Risk factors for fracture-related infection after open reduction and internal fixation of proximal humerus fractures: A multicenter retrospective study of 496 fractures (TRON group study)

INTRODUCTION

One of the complications of the surgical therapy for proximal humerus fractures is fracture-related infection (FRI). This multicenter study aimed to investigate the incidence of FRI and clarify the risk factors associated with FRI in patients receiving open reduction and internal fixation for proximal humerus fracture.

MATERIAL AND METHODS

Among 684 patients diagnosed as having proximal humerus fracture and who were treated by surgical therapy in 13 institutions (named TRON group) from 2015 through 2020, 496 patients (men, n = 134, women, n = 362; mean [SD] age, 68.5 [14.5] years; mean [SD] body mass index [BMI], 23.0 [4.4] kg/m²) were included as subjects. Excluded were 188 patients due to less than 12 month's follow-up, patients who underwent osteosynthesis using neither plate nor nail and those with open fracture. We extracted the following as risk factors of FRI: sex, BMI, smoking status, diabetes, glenohumeral fracture dislocation, fracture classification, approach, implant, waiting period, type of anesthesia, operative time and blood loss during surgery. We conducted logistic regression analysis to investigate the risk factors of FRI using these extracted items as explanatory variables and the presence or absence of FRI as the response variable.

RESULT

FRI occurred after surgery for proximal humerus fracture in 9 of the 496 patients (1.8%). The causative organism was methicillin-susceptible Staphylococcus aureus in 4 patients, Pseudomonas aeruginosa in one patient and Enterococcus faecalis in one patient. In the other 3 patients, causative organisms were not detected. The univariate analysis showed significant differences for present of glenohumeral fracture dislocation (p = 0.004). Logistic regression analysis showed glenohumeral fracture dislocation to be the significant explanatory factor for FRI (odds ratio 12.3, p = 0.0375).

CONCLUSION

This study revealed an infection rate following open reduction and internal fixation of proximal humerus fracture of 1.8% (9 patients) and that Staphylococcus was the most frequent causative organism. Glenohumeral fracture dislocation is a significant risk for postoperative FRI.

Effect of chronic kidney disease on outcomes following proximal humerus fragility fracture surgery in diabetic patients: A nationwide population-based cohort study

BACKGROUND

The proximal humerus fracture (PHF) is the third most common fragility fracture. Diabetes mellitus (DM) and chronic kidney disease (CKD) are both risks for fragility fractures; however, the interplay of DM and CKD makes treatment outcomes unpredictable. This study aimed to investigate and compare early and late outcomes following proximal humerus fracture fixation surgery in diabetic patients with different renal function conditions.

METHODS

DM patients receiving PHF fixation surgery during 1998-2013 were recruited from Taiwan's National Health Insurance Research Database. According to their renal function, patients were divided into three study groups: non-chronic kidney disease (CKD), non-dialysis CKD, and dialysis. Outcomes of interest were early and late perioperative outcomes. Early outcomes included in-hospital newly-onset morbidities. Late outcomes included infection, revision, readmission, and all-cause mortality.

RESULTS

This study included a total of 10,850 diabetic patients: 2152 had CKD (non-dialysis CKD group), 196 underwent permanent dialysis (dialysis group), and the remaining 8502 did not have CKD (non-CKD group). During a mean follow-up of 5.56 years, the dialysis group showed the highest risk of overall infection, all-cause revision, readmission, and mortality compared to the non-dialysis CKD group and non-CKD group. Furthermore, subgroup analysis showed that CKD patients had a higher risk of surgical infection following PHF surgery than non-CKD patients in cases with a traffic accident or fewer comorbidities (Charlson Comorbidity Index, CCI <3) (P for interaction: 0.086 and 0.096, respectively). Also, CKD patients had an even higher mortality risk after PHF surgery than non-CKD patients, in females, those living in higher urbanization areas, or with more comorbidities (CCI ≥3) (P for interaction: 0.011, 0.057, and 0.069, respectively).

CONCLUSION

CKD was associated with elevated risks for infection, revision, readmission, and mortality after PHF fixation surgery in diabetic patients. These findings should be taken into consideration when caring for diabetic patients.

The epidemiology of fracture-related infections in Germany

The epidemiology of fracture-related infection (FRI) is unknown, which makes it difficult to estimate future demands and evaluate progress in infection prevention. Therefore, we aimed to determine the nationwide burden’s development over the last decade as a function of age group and gender. FRI prevalence as a function of age group and gender was quantified based on annual ICD-10 diagnosis codes from German medical institutions between 2008 through 2018, provided by the Federal Statistical Office of Germany (Destatis). The prevalence of FRI increased by 0.28 from 8.4 cases per 100,000 inhabitants to 10.7 cases per 100,000 inhabitants between 2008 and 2018. The proportion of fractures resulting in FRI increased from 1.05 to 1.23%. Gender distribution was equal. Patients aged 60–69 years and 70–79 years comprised the largest internal proportion with 20.2% and 20.7%, respectively, whereby prevalence increased with age group. A trend towards more diagnoses in older patients was observed with a growth rate of 0.63 for patients older than 90 years. Increasing rates of fracture-related infection especially in older patients indicate an upcoming challenge for stakeholders in health care systems. Newly emerging treatment strategies, prevention methods and interdisciplinary approaches are strongly required.

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.

Single versus Double Skin Preparation for Infection Prevention in Proximal Humeral Fracture Surgery

Preoperative skin preparation plays a major role in preventing postoperative infections. This study aims to compare a single skin preparation (povidone iodine) with a double skin preparation (chlorhexidine gluconate followed by povidone iodine). Forty patients affected by proximal humeral fracture were included in the study. The day of surgery the two skin preparation strategies were performed in the same shoulder, divided into two areas, at the level of the deltopectoral approach. Skin swabs were collected from each area and subjected to microbiological analysis. Both skin preparations significantly reduced the positive culture rate. Coagulase-negative staphylococci (CoNS) dropped from 92.5% to 40% and to 7.5% after the single and double skin preparation (p<0.001), respectively. The positivity rate was reduced from 50% to 17.5% (p=0.002) and from 27.5% to 0% (p= 0.001) for Propionibacterium acnes and Staphylococcus aureus, respectively, with no difference between the two preparations. The double skin preparation had a more significant effect on bacterial load against CoNS compared to the single skin preparation (p<0.001 versus p= 0.015). In conclusion, both the approaches reduced S. aureus and P. acnes skin load, whereas the double skin preparation is more effective than the single one against CoNS. In light of our findings, preoperative strategies able to reduce bacterial load could potentially increase the final efficacy of perioperative traditional skin preparations.

Propionibacterium acnes Infection of the Shoulder After a Manipulation Under Anesthesia for Stiffness Status Post Open Reduction and Internal Fixation Proximal Humerus: A Case Report

Introduction

Propionibacterium acnes infection has been more frequently recognized as an important cause of post-operative shoulder infection. Infection by this organism is more frequently seen after total shoulder arthroplasty but can also be seen after an open reduction and internal fixation (ORIF) of the proximal humerus. We present a patient with P. acnes infection of the shoulder that only became apparent after he underwent a manipulation under anesthesia for stiffness of the shoulder after an ORIF.

Case Report

Our patient was a 64-year-old male who sustained a proximal humerus fracture after a motorcycle collision and underwent an ORIF of the proximal humerus with plate fixation. Postoperatively, the patient had stiffness of the shoulder so he underwent a manipulation under anesthesia of the shoulder. On post-operative day 5, the patient developed an erythematous area over the incision. This area opened up and began to drain by post-operative day 10. The patient underwent an irrigation and debridement of the shoulder with partial removal of hardware. He was also started on antibiotics and clinically cleared his infection.

Conclusion

Infection by P. acnes can be difficult to diagnose and may present with shoulder stiffness as the only initial symptom. This case is unique as there have not been any documented cases of a latent P. acnes infection presenting after a manipulation under anesthesia of the shoulder. There must be a high clinical suspicion for P. acnes infection in any patient presenting with post-operative stiffness.

Effect of surgical delay on bacterial colonization in proximal humeral fractures

Postoperative infection is a severe complication after proximal humeral fracture surgical treatment. The aim of this study was to determine if the surgical delay could modify the number and type of bacteria on the surgical site. A two stages study was set up. In the first stage the effect of delay was simulated in 20 patients affected by proximal humeral fracture treated conservatively. In a second stage, the effect of delay was measured in 20 patients that underwent surgery. In stage 1, three skin culture swabs were taken in correspondence of the deltopectoral approach, the day of the fracture (day 0), the day after (day 1), and five days after fracture (day 5). In stage 2, skin swab cultures were taken the day of trauma and immediately before surgery and cultured on various media suitable for aerobic and anaerobic bacteria. The number of bacteria increased over the course of the study, from day 0 to day 5, both considering the total number of colony-forming units and individual species of pathogen bacteria. The second stage of the study confirmed these data. An increasing number of bacteria was observed in patients that underwent surgery later than 2 days from trauma. The delay of surgery increased bacterial colonization of the skin in the deltopectoral approach area including common pathogenic bacteria such as Staphylococcus aureus, coagulase-negative staphylococci and Propionibacterium acnes. This might justify the correlation between delay to surgery and risk of infection. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:942-948, 2016.

What Factors are Associated With a Surgical Site Infection After Operative Treatment of an Elbow Fracture?

BACKGROUND

Surgical site infections are one of the more common major complications of elbow fracture surgery and can contribute to other adverse outcomes, prolonged hospital stays, and increased healthcare costs.

QUESTIONS/PURPOSES

We asked: (1) What are the factors associated with a surgical site infection after elbow fracture surgery? (2) When taking the subset of closed elbow fractures only, what are the factors associated with a surgical site infection? (3) What are the common organisms isolated from an elbow infection after open treatment?

METHODS

One thousand three hundred twenty adult patients underwent surgery for an elbow fracture between January 2002 and July 2014 and were included in our study. Forty-eight of 1320 patients (4%) had a surgical site infection develop. Thirty-four of 1113 patients with a closed fracture (3%) had a surgical site infection develop.

RESULTS

For all elbow fractures, use of plate and screw fixation (adjusted odds ratio [OR]= 2.2; 95% CI, 1.0-4.5; p = 0.041) and use of external fixation before surgery (adjusted OR = 4.7; 95% CI, 1.1-21; p = 0.035) were associated with higher infection rates. When subset analysis was performed for closed fractures, only smoking (adjusted OR = 2.2; 95% CI, 1.1-4.5; p = 0.023) was associated with higher infection rates. Staphylococcus aureus was the most common bacteria cultured (59%).

CONCLUSIONS

The only modifiable risk factor for a surgical site infection after open reduction and internal fixation was cigarette smoking. Plate fixation and temporary external fixation are likely surrogates for more complex injuries, therefore no recommendations should be inferred from this association. Surgeons should counsel patients who smoke.

LEVEL OF EVIDENCE

Level IV, prognostic study.

Trends in surgical site infections following orthopaedic surgery

PURPOSE OF REVIEW

This review presents an update on recent findings relating to the prevention, control and epidemiology of infections following orthopaedic surgery.

RECENT FINDINGS

Trends in population rates and characteristics of patients undergoing hip and knee replacement surgery, coupled with the reported excess infection risk in obese patients, emphasize the current and future impact of increasing population obesity on healthcare delivery.

SUMMARY

Prevention of orthopaedic infection is dependent on elimination or optimal management of documented risk factors. Guidelines and quality standards play a key role in translating this evidence base into a framework of practices for the prevention of surgical site infections. Increasing levels of orthopaedic infection due to Enterobacteriaceae, coupled with an increasingly obese surgical population may necessitate a reassessment of antimicrobial prophylaxis strategies.

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

BACKGROUND

Existing hardware may contribute to increased risk of bacterial contamination and subsequent periprosthetic joint infection (PJI) in conversion shoulder arthroplasty performed for failed fracture fixation.

QUESTIONS/PURPOSES

This study examined the incidence of positive pre-operative aspiration and inflammatory marker data, along with correlation of pre-operative positive aspiration or inflammatory markers and subsequent infection following conversion shoulder arthroplasty for failed open reduction and internal fixation (ORIF) and the need for re-operation at 4.6-year follow-up.

METHODS

Twenty-eight patients who underwent conversion to shoulder arthroplasty for any reason after fracture fixation were retrospectively reviewed in a single center. A pre-operative aspiration was done in 17 patients; all patients had intra-operative tissue sampling. All procedures were single-stage removal of hardware and performance of the arthroplasty. In cases of pre-operative positive bacterial growth, a single-stage procedure was performed according to the septic ENDO-Klinik protocol.

RESULTS

In 4 of 17 pre-operative joint aspirations, bacterial growth was detected; one pre-operative negative aspiration demonstrated bacterial growth in intra-operative sampling. In three of them, the infection has been validated through intra-operatively results. Pre-operative aspiration showed a sensitivity of 75% and specificity of 92% (p < 0.005) for infection. No post-operative PJIs were observed. Six revisions were performed, most commonly for aseptic loosening (two cases) and conversion of hemiarthroplasty to a reverse design (two cases).

CONCLUSIONS

In conclusion, the risk of low-grade shoulder infection after fracture osteosynthesis may be higher than in hip and knee joints, based on limited study data. Adequate pre-operative testing is recommended to rule out occult shoulder infection in this setting.

Geriatric proximal humeral fracture patients show similar clinical outcomes to non-geriatric patients after osteosynthesis with endosteal fibular strut allograft augmentation

BACKGROUND

Osteosynthesis of proximal humeral fractures is challenging in geriatric patients. The purpose of this investigation was to compare postoperative clinical outcomes between cohorts of geriatric (aged ≥65 years) and non-geriatric proximal humeral fracture patients treated via locked plating with endosteal fibular strut allograft augmentation.

METHODS

From March 2007 to January 2013, 71 adult patients with 2-, 3-, and 4-part proximal humeral fractures according to the Neer classification underwent osteosynthesis with locked plating and fibular allograft augmentation and had at least 12 months of clinical follow-up. All patients followed the same postoperative rehabilitation protocol. We compared the following between geriatric and non-geriatric patients: Disabilities of the Arm, Shoulder and Hand scores; University of California, Los Angeles shoulder ratings; Constant-Murley scores; and range of motion; as well as injury characteristics and radiographic outcomes.

RESULTS

Geriatric patients comprised 48% of the study cohort (34 of 71 patients). The mean age of the geriatric and non-geriatric cohorts was 74 years and 53 years, respectively. Geriatric patients showed significantly reduced forward flexion (147° vs 159°, P = .04) when compared with non-geriatric patients. There were no significant differences in functional scores, radiographic outcomes, or complication rates between the 2 cohorts, although in 1 geriatric patient, osteonecrosis developed and screw penetration through the collapsed head was present 3 years after surgery.

CONCLUSIONS

Osteosynthesis of proximal humeral fractures via locked plating with fibular strut allograft augmentation results in similar clinical outcomes between geriatric and non-geriatric patients. We believe that enhanced stability provided by this fixation construct allows early intensive postoperative therapy and results in excellent outcomes despite patient age.

Plate osteosynthesis versus hemiarthroplasty in proximal humerus fractures--does routine screening of systemic inflammatory biomarkers makes sense?

Background

Increases in C-reactive protein (CRP) and white blood cell (WBC) counts after orthopedic surgical procedures can give evidence of postoperative infection. However, there is a lack of knowledge about the kinetics of these biomarkers in cases with an uneventful clinical course after osteosynthesis of upper limb fractures. This study investigated CRP and WBC serum levels after osteosynthesis or hemiarthroplasty of humeral head fractures.

Methods

A retrospective study on patients with humeral head fractures who had open reduction and internal fixation via plate osteosynthesis (PO) (n = 64) or hemiarthroplasty (HA) (n = 28) without any complications in the postoperative clinical course. C-reactive protein serum levels (mg/l) and leukocyte counts (g/l) were assayed at several time points. Multiple regression analysis was performed to evaluate the influence of several confounding variables (the surgical procedure, duration of surgery, patient’s health status, and comorbidities) on the kinetics of CRP and WBC.

Results

Our data showed that CRP levels were statistically significantly higher in the HA cohort when compared to the PO cohort (p = 0.003). Moreover, daily measurement of CRP levels during the postoperative course showed that CRP peaked on the 2nd and 3rd days postoperatively in both cohorts and started to decrease afterward, reaching normal values on day 8 to 10. However, WBCs did not show any significant differences between the HA and PO cohorts. Finally, the choice of surgical procedure and the patient’s health status were associated with higher peak levels of CRP.

Conclusions

After osteosynthesis or hemiarthroplasty of humeral head fractures, CRP is a responsive serum parameter in the postoperative course of an uneventful inflammatory response. Abnormalities from these values should be interpreted carefully as they may give a hint as to postoperative complications such as infection.