Mechanical complications of hip spacers: a systematic review of the literature.

INTRODUCTION: Temporary spacers used in the staged revision of a hip prosthetic joint infection (PJI) have been associated with several mechanical complications with very variable reported general complications rates up to 73%. The aim of this systematic review was to assess the mechanical complications associated with hip antibiotic-loaded spacers when treating periprosthetic hip PJI. METHODS: Through an electronic systematic search of PubMed, articles reporting mechanical complications of spacers used in the treatment of hip PJI were reviewed. Dislocations, spacer fracture, femoral fractures, and acetabular lysis rates were evaluated. RESULTS: Forty studies were included. Standardized molded spacers had a significantly higher weighted mean of total mechanical complication rates (37.2%) when compared to standardized preformed spacers (13.8%, p = 0.039), while no significant difference was found between molded spacers and manually shaped spacers. Spacer dislocation was the most frequent complication. No significant difference in mechanical complication rate was found between spacers with and without any metallic component. CONCLUSIONS: Spacer placement in chronic PJI of the hip with bone and soft-tissue defects is challenging and bears a high risk of mechanical failures and progressive bone loss during the interim period. A careful patient selection for spacer implantation is mandatory.

Risk factors for postoperative coronal imbalance after surgical correction of adult spinal deformities: a systematic review with pooled analysis.

OBJECTIVE: The aim of this study was to identify preoperative risk factors for postoperative coronal imbalance (CIB) in patients undergoing surgical correction for adult spinal deformity (ASD). METHODS: A systematic search of articles about risk factors for postoperative CIB was conducted on electronic databases (PubMed, EMBASE, and Cochrane Library) according to the PRISMA guidelines. The methodological quality of the included articles was assessed using the Institute of Health Economics Quality Appraisal Checklist for Case Series Studies. Data regarding the patient population (demographics, diagnosis, and follow-up), pre- and postoperative radiographic and clinical data, surgical procedure details, and complications were extracted and summarized. Meta-analyses were performed when possible. RESULTS: Nine studies comprising 838 patients were included. The pooled incidence of postoperative CIB was 26%; preoperative sagittal vertical axis (SVA) and type C imbalance (trunk shifted toward the convexity) were found to be the only primary risk factors for iatrogenic CIB (p < 0.001 and p = 0.012, respectively). CONCLUSIONS: Baseline evaluation of a patient's global alignment is of outmost importance when planning surgery for ASD. Type C coronal imbalance (trunk shifted toward the convexity of the main curve) and increased preoperative SVA put the patient at risk of postoperative CIB. Intraoperatively, care should be taken to properly correct the lumbosacral fractional curve.

Functional Outcome after Reimplantation in Patients Treated with and without an Antibiotic-Loaded Cement Spacers for Hip Prosthetic Joint Infections.

Purpose: A staged revision with placement of a temporary antibiotic-loaded cement spacer after removal of the implant is the "gold standard" for treatment of chronic prosthetic joint infection (PJI). It enables local delivery of antibiotics, maintenance of limb-length and mobility, easier reimplantation. However, bacterial colonization of spacers and mechanical complications can also occur. The aim of this study is to evaluate functional results and infection control in two-stage treatment of total hip arthroplasty (THA) PJI with and without a spacer. Materials and Methods: A retrospective review of 64 consecutive patients was conducted: 34 underwent two-stage revision using a cement spacer (group A), 30 underwent two-stage revision without a spacer (group B). At the final follow-up, functional evaluation of patients with a THA in site, without PJI recurrence, was performed using the Harris hip score (HHS). Measurement of limb-length and off-set discrepancies was performed using anteroposterior pelvic X-rays. Results: Most patients in group B were older with more comorbidities preoperatively. Thirty-three patients (97.1%) in group A underwent THA reimplantation versus 22 patients (73.3%) in group B (P<0.001). No significant differences in limb-length and off-set were observed. The results of functional evaluation performed during the final follow-up (mean, 41 months) showed better function in patients in group A (mean HHS, 76.3 vs. 55.9; P<0.001). Conclusion: The use of antibiotic-loaded cement spacer seems superior in terms of functional outcomes and reimplantation rate. Resection arthroplasty might be reserved as a first-stage procedure in patients who are unfit, who might benefit from a definitive procedure.

Independent Risk Factors of Postoperative Coronal Imbalance after Adult Spinal Deformity Surgery.

The aim of the present study is to elucidate preoperative risk factors for inadequate correction of coronal imbalance and/or creation of new postoperative coronal imbalance (iatrogenic CIB) in patients who undergo surgery for Adult Spinal Deformity (ASD). A retrospective review of adults who underwent posterior spinal fusion (>5 levels) for ASD was performed. Patients were divided into groups according to the Nanjing classification: type A (CSVL < 3 cm), type B (CSVL > 3 cm and C7 plumb line shifted to major curve concavity), and type C (CSVL > 3 cm and C7 plumb line shifted to major curve convexity). They were also divided according to postoperative coronal balance in balanced (CB) vs. imbalanced (CIB) and according to iatrogenic coronal imbalance (iCIB). Preoperative, postoperative, and last follow-up radiographical parameters and intraoperative data were recorded. A multivariate analysis was performed to identify independent risk factors for CIB. A total of 127 patients were included (85 type A, 30 type B, 12 type C). They all underwent long (average levels fused 13.3 ± 2.7) all-posterior fusion. Type C patients were more at risk of developing postoperative CIB (p = 0.04). Multivariate regression analysis indicated L5 tilt angle as a preoperative risk factor for CIB (p = 0.007) and indicated L5 tilt angle and age as a preoperative independent risk factors for iatrogenic CIB (p = 0.01 and p = 0.008). Patients with a preoperative trunk shift towards the convexity of the main curve (type C) are more prone to postoperative CIB and leveling the L4 and L5 vertebrae is the key to achieve coronal alignment preventing the "takeoff phenomenon".

Are Static Spacers Superior to Articulated Spacers in the Staged Treatment of Infected Primary Knee Arthroplasty? A Systematic Review and Meta-Analysis.

In the treatment of knee periprosthetic joint infection with a two-stage protocol, static spacers allow for the local delivery of high doses of antibiotics and help to preserve soft tissue tension. Articulated spacers were introduced to better preserve flexion after the reimplantation. The aim of this systematic review is to provide a comprehensive data collection of the results of these different spacers. An in-depth search on the main clinical databases was performed concerning the studies reporting data on the topic. A total of 87 studies and 4250 spacers were included. No significant differences were found both in pooling data analysis and meta-analysis of comparative studies about infection recurrences, complications, and clinical scores. Mean active knee flexion at last follow-up after total knee reimplantation was found to be significantly higher using articulated spacers (91.6° ± 7° for static spacers vs. 100.3° ± 9.9° for articulated spacers; p < 0.001). Meta-analysis also recognized this strong significant difference (p < 0.001). This review has confirmed that articulated spacers do not appear to be inferior to static spacers regarding all clinical outcomes, while they are superior in terms of active flexion. However, the low quality of the studies and the risk for selection bias with complex patients preferentially treated with static spacers need to be accounted for.

Epidemiology of Fungal Periprosthetic Joint Infection: A Systematic Review of the Literature.

Fungal prosthetic joint infection (fPJI) is a rare complication; nonetheless, it represents a significant diagnostic and therapeutic challenge. There are no official guidelines on the most effective approach to identify and treat fPJIs. This systematic review aims to review the current literature on fPJI management and provide a comprehensive overview of this topic, especially from an epidemiologic point of view. Studies eligible for this systematic review were identified through an electronic systematic search of PubMed, Scopus, and Web of Science until 30 September 2022. Further references were obtained by cross-referencing. Sixty-three studies met the inclusion criteria, reporting on 372 cases of fPJI; such cases were described mostly in case reports and small case series with only a few larger cohort studies. Diagnosis of fPJI is challenging because of its chronic and indolent clinical course; it is further complicated by the technical difficulty of harvesting fungal cultures. A two-stage revision was the primary procedure in 239 (64.2%) patients whereas DAIR and one-stage approaches were reported in 30 (8.0%) and 18 (4.8 %) cases. In conclusion, our study highlights the heterogeneity of the reported treatments of fPJI, particularly in terms of medical management. With concern to a surgical approach, a two-stage revision arthroplasty is generally suggested, considering fPJI a delayed or late infection. The need for multicenter, prospective studies to provide standardized protocols and improve the treatment of fungal PJI clearly emerges.