Outcomes of hip arthroplasty with concomitant hardware removal: influence of the type of implant retrieved and impact of positive intraoperative cultures

Unexpected positive cultures in conversion hip and knee arthroplasty

PURPOSE

Total hip and knee arthroplasty in patients with previous history of periarticular surgery, such as osteosynthesis, can be surprisingly complex. This type of procedure is known as conversion arthroplasty (cTHA or cTKA) and has a higher risk of complications. The rates of unexpected positive cultures (UPC) and the risk of periprosthetic joint infection (PJI) compared to primary arthroplasty is unclear. The main purpose of this study was to evaluate rates of Unexpected Positive Cultures (UPC) in a series of conversion arthroplasty patients. The main questions to answer are: 1. Are the patients with conversion arthroplasties more susceptible to UPC than other causes of revision arthroplasties? 2. Are the conversion patients with UPC more susceptible to developing PJI?

METHODS

This was a retrospective review of patients submitted to cTHA and cTKA from January 2012 to September 2018. Patients with history of previous infection or with missing intraoperative cultures were excluded. The UPC was defined as a single positive culture obtained during a procedure previously considered aseptic and PJI was defined according to the 2018 ICM criteria. After excluding 141 cases, 205 patients were analyzed, 160 hips and 45 knees.

RESULTS

Nine (4.4%) UPC were identified, five (3.1%) in the hip group and four (8,9%) in the knee group. Staphylococcal species were the most common isolated bacteria (n = 7, 77.7%). During the study period, four (1,9%) patients were diagnosed with PJI. Only one case had an UPC and a different germ was identified during revision arthroplasty workup.

CONCLUSIONS

While UPC are more prevalent in conversion knee arthroplasties compared to conversion hip arthroplasties, the rates are similar to those observed in revision arthroplasty for other indications. Importantly, the presence of a UPC in conversion arthroplasty does not appear to elevate the risk of subsequent periprosthetic joint infection, provided a thorough PJI workup has been conducted preoperatively. Therefore, in such cases, UPCs may be safely disregarded.

Surgical Time and Complication Risk in Conversion Total Hip Arthroplasty With Implant Removal: Finding an Optimal Surgical Duration

BACKGROUND

Although longer surgical times in primary total hip arthroplasty (THA) are associated with higher complication rates, this has yet to be explored in conversion THA. The purpose of this study is to investigate the relationship between surgical time and complications in the setting of conversion THA with implant removal. We aim to establish a length of surgery after which the risk of complications increases.

METHODS

This was a retrospective study conducted at a single institution. A total of 260 conversion THAs performed between 2015 and 2021 were included. An area under the curve (AUC) was constructed to determine a surgery time that increased the likelihood of complications. Logistic regressions were run to determine predictors for longer surgical times and complications.

RESULTS

The overall complication rate of conversion THA involving implant removal was 25.8% (67 patients). Surgical times greater than 114 minutes were found to be a predictor of complications (AUC: 0.700, 95% Confidence Interval [CI]: 0.630 to 0.771), with complications 6 times as likely in these cases (9.57% vs. 34.9%, P < 0.001). Regression analysis revealed that index implants of cephalomedullary nails ( P < 0.001, odds ratio [OR]: 17.47) and dynamic hip screw plates ( P < 0.001, OR: 10.9) were notable predictors of surgical times greater than 114 minutes along with higher body mass index ( P = 0.005, OR: 1.10). Higher body mass index and surgical times greater than 114 minutes were also found to be predictors of complications ( P = 0.035, OR: 0.93; P < 0.001, 6.37).

CONCLUSION

Conversion THA cases involving implant removal that are longer than 114 minutes are associated with higher complication rates and revision surgeries. Conversion THA requiring implant removal of cephalomedullary nails or dynamic hip screw plates were predictors for longer surgical times. Improved surgical planning and perioperative patient optimization may be viable options to limit surgical times. This information can be used to counsel patients on the risk of complications and the possibility of a staged procedure if appropriate.

Dynamic hip screw in proximal femoral fractures followed by "single-stage" hip arthroplasty-retrospective analysis

The aim of this study is to present the results of single-stage total hip arthroplasty (THA) after Dynamic Hip Screw (DHS) failure, or secondary posttraumatic osteoarthrosis. From 2003 to 2020, 15 THAs were performed in group of 15 patients for the treatment of DHS failure, or for late complications following femoral neck and pertrochanteric fractures. The mean follow-up period after arthroplasty was 46.9 months (range 7-139). The patients were evaluated retrospectively-both clinically and radiographically, focussing on the demography, infection rate and other complications (revision surgery), during the year 2023. 9 males and 6 females were included in the study, with a mean age of 56.5 years (range 29-93) at the time of primary osteosynthesis. Each of them had proximal femoral fracture treated primarily with a DHS and then late one-stage revision surgery, with hardware removal and THA implantation. The median time between DHS osteosynthesis and THA was 41.2 months (range 4-114). Four patients (26.6%) had complications after THA, with the need for revision in two cases (13.3%). Dislocation rate was 6.6% (one case), with the need for repeated-revision of THA. The infection rate was 6.6% (one patient) with the need for revision of THA. Peroperative periprosthetic femoral fracture was observed in 13.3% (two patients) without any other problems. Six patients (40%) died during the follow-up period. Single-stage total hip arthroplasty with concomitant hardware removal bears a high- mortality rate, with a higher incidence of postoperative complications compared to elective THA.

Decreased Risk of Periprosthetic Joint Infection with Concurrent Hardware Removal During Conversion Total Hip Arthroplasty Compared to Staged Removal: A Matched Cohort Analysis

INTRODUCTION

Hardware removal before conversion total hip arthroplasty (cTHA) is a challenging task for the orthopaedic surgeon, although there is little consensus on the timing of hardware removal to mitigate risk of surgery-related complication following cTHA.

METHODS

Using a national insurance database, we evaluated patients who underwent hardware removal either on the same day or within 1 year before cTHA, resulting in a total of 7,756 patients. After matching based on demographic factors and comorbidities, both staged and concurrent groups consisted of 2,752 patients. The 90-day and 1-year risk of revision surgery, periprosthetic joint infection (PJI), periprosthetic fracture, and aseptic loosening were calculated and compared. Demographic factors and comorbidities were further evaluated as risk factors for PJI.

RESULTS

The rates of infection were 1.85% and 3.05% at 90 days postoperatively and 2.94% and 4.14% at 1 year postoperatively for concurrent versus staged cohorts, respectively (P = 0.004 and P = 0.02). No difference was observed at 90 days or 1 year between the two cohorts in risk of fracture, revision surgery, or aseptic loosening. Diabetes (P = 0.002 and P < 0.001), tobacco use (P < 0.001 and P < 0.001), and obesity (P = 0.026 and P = 0.025) were identified as risk factors for PJI at both 90 days and 1 year postoperatively.

DISCUSSION

The timing of hardware removal is associated with an increased risk of PJI, although no difference was observed in revision surgery, fracture, or loosening among staged versus concurrent cohorts. These findings are important to consider when surgeons are evaluating patients with periarticular implants surrounding their hip.

Clinical Outcomes and Complication Rate after Single-Stage Hardware Removal and Total Hip Arthroplasty: A Matched-Pair Controlled Study

BACKGROUND

Single-stage hardware removal and total hip arthroplasty is a complex surgical procedure, comparable to revision surgery. The purpose of the current study is to evaluate single-stage hardware removal and THA outcomes, compare this technique with a matched control group that has undergone primary THA and assess the risk of periprosthetic joint infection with a 24-month minimum follow-up.

METHODS

This study included all those cases treated with THA and concomitant hardware removal from 2008 to 2018. The control group was selected on a 1:1 ratio among patients who underwent THA for primary OA. The Harris Hip (HHS) and University of California at Los Angeles Activity (UCLA) scores, infection rate and early and delayed surgical complications were recorded.

RESULTS

One hundred and twenty-three consecutive patients (127 hips) were included, and the same number of patients was assigned to the control group. The final functional scores were comparable between the two groups; a longer operative time and transfusion rate were recorded in the study group. Finally, an increased incidence of overall complications was reported (13.8% versus 2.4%), but no cases of early or delayed infection were found.

CONCLUSIONS

Single-stage hardware removal and THA is a safe and effective but technically demanding technique, with a higher incidence of overall complications, making it more similar to revision THA than to primary THA.