Outcomes of primary total hip arthroplasty following septic arthritis of the hip : a case-control study

Should treatment decisions in septic arthritis of the native hip joint be based on the route of infection?

Background: Surgical management of septic arthritis (SA) of the hip aims at treating the infection by either preserving, resecting or replacing the joint. In some cases, joint preservation should be attempted, whereas other cases would benefit from immediate joint resection or replacement. Prognostic factors have been proposed to guide decision-making. We hypothesized that most of these factors can be simplified to three subgroups based on the route of infection: contiguous spreading, direct inoculation or hematogenous seeding. Methods: A total of 41 patients have been treated surgically for SA of the native hip at our tertiary hospital during the last 16 years. Medical records were studied, and various patient and disease characteristics were collated. Results: Significant differences between (1) level of fitness, (2) condition of the hip joint, (3) micro-organisms and (4) chance of femoral head preservation were found for patients with SA of the native hip resulting from the three aforementioned subgroups. Femoral head resection was necessary at one point in 85 % of patients. Patients with hematogenous infections of undamaged hips had a reasonable chance (53 %) of avoiding joint resection or replacement. Hip arthroplasty was performed on 46.3 % of patients, with an infection rate of 10.5 %. Conclusion: Patients with SA of the native hip resulting from contiguous spreading, hematogenous seeding or direct inoculation differ significantly and should be considered distinct clinical entities. Route of infection is directly related to the chance of femoral head preservation and should, therefore, guide decision-making. Only patients with hematogenous infection to a previously healthy hip had the possibility of femoral head preservation.

Contemporary outcomes of primary total hip arthroplasty in patients with inflammatory arthritis

Aims

Contemporary outcomes of primary total hip arthroplasties (THAs) with highly cross-linked polyethylene (HXLPE) liners in patients with inflammatory arthritis have not been well studied. This study examined the implant survivorship, complications, radiological results, and clinical outcomes of THA in patients with inflammatory arthritis.

Methods

We identified 418 hips (350 patients) with a primary diagnosis of inflammatory arthritis who underwent primary THA with HXLPE liners from January 2000 to December 2017. Of these hips, 68% had rheumatoid arthritis (n = 286), 13% ankylosing spondylitis (n = 53), 7% juvenile rheumatoid arthritis (n = 29), 6% psoriatic arthritis (n = 24), 5% systemic lupus erythematosus (n = 23), and 1% scleroderma (n = 3). Mean age was 58 years (SD 14.8), 66.3% were female (n = 277), and mean BMI was 29 kg/m² (SD 7). Uncemented femoral components were used in 77% of cases (n = 320). Uncemented acetabular components were used in all patients. Competing risk analysis was used accounting for death. Mean follow-up was 4.5 years (2 to 18).

Results

The ten-year cumulative incidence of any revision was 3%, and was highest in psoriatic arthritis patients (16%). The most common indications for the 15 revisions were dislocations (n = 8) and periprosthetic joint infections (PJI; n = 4, all on disease-modifying antirheumatic drugs (DMARDs)). The ten-year cumulative incidence of reoperation was 6.1%, with the most common indications being wound infections (six cases, four on DMARDs) and postoperative periprosthetic femur fractures (two cases, both uncemented femoral components). The ten-year cumulative incidence of complications not requiring reoperation was 13.1%, with the most common being intraoperative periprosthetic femur fracture (15 cases, 14 uncemented femoral components; p = 0.13). Radiological evidence of early femoral component subsidence was observed in six cases (all uncemented). Only one femoral component ultimately developed aseptic loosening. Harris Hip Scores substantially improved (p < 0.001).

Conclusion

Contemporary primary THAs with HXLPE in patients with inflammatory arthritis had excellent survivorship and good functional outcomes regardless of fixation method. Dislocation, PJI, and periprosthetic fracture were the most common complications in this cohort with inflammatory arthritis.

Less Than 1-Year Quiescent Period After Septic Arthritis of the Hip is Associated With High Risk of Periprosthetic Joint Infection Following Total Hip Arthroplasty

BACKGROUND

Approximately 20,000 patients are diagnosed with septic arthritis annually, with 15% specifically affecting the hip joint. These cases exacerbate arthritic changes, often warranting a total hip arthroplasty (THA). Given their prior history of infection, these patients are predisposed to subsequent periprosthetic joint infections (PJIs). Multiple studies suggest delaying THA after a native septic hip, but no study utilizing a large cohort examined the specific timing to mitigate post-THA PJI risk within a short (<1 year) quiescent period after septic arthritis. We sought to compare patients who were diagnosed with septic hip arthritis at time intervals (0-6, or 6-12 months) prior to an ipsilateral primary THA to a cohort of THA patients who never had a septic hip history. Specifically, we assessed: from 90 days to 2 years (1) revisions due to PJI and (2) associated risk factors for PJI at 2-years.

METHODS

A national, all-payer database was queried to identify all patients who underwent a primary THA between 2010 and 2021 and patients who had prior ipsilateral septic hip arthritis were characterized using International Classification of Disease and Current Practice Terminology codes (n = 1,052). A randomized sample of patients who never had a history of septic arthritis prior to undergoing THA was used as a nonseptic group comparison (n = 5,000). The incidences of PJI at 90 days through two years were then identified and compared using bivariate chi-square analyses. Risk factors for post-THA PJIs were then analyzed using multivariate regression models.

RESULTS

The septic arthritis cohorts were more likely to require revisions due to PJIs, as compared to the non-septic group at 90 days, 1 year, and 2 years (all P < .0001). Patients who were diagnosed with septic arthritis between 0 and 6 months prior to THA were at greater PJI risk at both one-year (odds ratio (OR) of 43.1 versus 29.6, P < .0001) and two years (OR of 38.3 versus 22.1, P < .0001) compared to patients who had diagnoses between 6 and 12 months. Diabetes mellitus, obesity, and tobacco use were associated risk factors for PJIs at 2 years in the septic hip cohort in comparison to the cohort without a septic hip history.

CONCLUSION

Less than a 1-year quiescent period after septic arthritis is associated with a 38 times increased risk and a 22 times risk for post-THA PJI, at 0 and 6 months and 6 and 12 months, respectively. Though patients who undergo THA greater than 6 months after their septic arthritis treatment have a decreased risk compared to those between 0 and 6 months the risks are still high. Orthopaedic surgeons should be aware of the increased risks of PJIs when considering performing a THA in patients with a history of septic arthritis.

Arthroplasty after septic arthritis of the native hip and knee: retrospective analysis of 49 joints

Abstract. Background: Arthroplasty after septic arthritis (SA) treatment raises diagnostic and therapeutic questions. The main objective was to evaluate infection-free survival of patients undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA) post-SA. Other objectives were to describe the population's characteristics, surgical strategies, results of preoperative examinations and cultures of intraoperative samples taken at implantation, and postoperative antibiotic therapy. Methods: This is a retrospective, observational, monocenter study, from January 2005 to May 2019, including all patients undergoing TKA or THA with prior or ongoing SA in the same joint. Infection–free survival was analyzed and reported. Results: Forty-seven patients, 29 men, 49 joints operated on (30 knees, 19 hips), were included. Median SA-to-arthroplasty interval was 32 [1–216] weeks. It was <2 years for 43 joints and <6 months for 19 joints. Six patients underwent arthroplasty while still on SA treatment. One-stage arthroplasty was done for 43 joints and two-stage arthroplasty for 6 joints. Eight (16 %) cultures of intraoperative specimens were positive. Median durations of postoperative antibiotic therapy were 10 d for sterile cultures and 82 d for those that were positive. At 2 years, infection-free survival rate was 95.9 % (±0.02). After a median follow-up of 47 [18–142] months, no SA relapse was observed, but five patients developed new periprosthetic joint infections (PJIs) with a different microorganism. Conclusion: Arthroplasty may be a post-SA option, even within a short period of time. One-stage arthroplasty can be done if synovectomy is thorough, intraoperative samples are taken and antibiotics are administered until those culture results become available. We observed no SA relapse, but new PJIs occurred.