Domenico Albano1,2, Carmelo Messina1,3, Luigi Zagra4, Mauro Andreata4, Elena De Vecchi5, Salvatore Gitto3, Luca M Sconfienza1,3. 1. IRCCS Istituto Ortopedico Galeazzi, Unità Operativa di Radiologia Diagnostica ed Interventistica, Milan, Italy. 2. Sezione di Scienze Radiologiche, Dipartimento di Biomedicina, Neuroscienze e Diagnostica Avanzata, Università degli Studi di Palermo, Palermo, Italy. 3. Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Milan, Italy. 4. IRCCS Istituto Ortopedico Galeazzi, Hip Department, Milan, Italy. 5. IRCCS Istituto Ortopedico Galeazzi, Laboratory of Clinical Chemistry and Microbiology, Milan, Italy.
Abstract
BACKGROUND: Very little has been published about the diagnostic performance of MRI in total hip arthroplasty (THA) infection. PURPOSE: To determine the diagnostic performance of conventional MRI features and of new lymph nodal indices to identify infection in patients with failed THA. STUDY TYPE: Retrospective. POPULATION: In all, 119 patients (66 females; age 66.9 ± 12.4 years) with failed THA. FIELD STRENGTH/SEQUENCES: Metal artifact reduction sequence (MARS) protocol including short tau inversion recovery and turbo spin-echo T1 - and T2 -weighted sequences at 1.5T. ASSESSMENT: Patients underwent pelvis MRI prior to failed THA revision. MRIs were reviewed to identify periprosthetic bone destruction, soft-tissue mass, effusion, synovitis, lamellated synovitis, extracapsular edema, fibrous periprosthetic membrane, bone edema, and extracapsular collection/sinus tract. The number and maximum diameter of inguinal, obturator and iliac lymph nodes of the affected hip were assessed and normalized to those of the unaffected hip to calculate the ratio of nodal size (RNS), ratio of node number (RNN), difference of nodal size (DNS), and difference of node number (DNN). STATISTICAL TESTS: The Mann-Whitney U-and chi-square test were used. Diagnostic performance of indices and odds ratios (OR) were calculated. RESULTS: RNS, RNN, DNS, and DNN indices were significantly different (P = 0.000) between infected and noninfected THA, with accuracies ranging from 84.8% (RNS) and 93.1% (RNN). All other MRI features were significantly more prevalent in infected THA (P ≤ 0.002), except bone destruction, periarticular soft-tissue mass, and fibrous membrane (P ≥ 0.031). Sensitivities ranged from 7.9% (soft-tissue mass) to 76.3% (effusion/bone edema), specificity from 45.7% (bone destruction) to 97.5% (synovitis/lamellated synovitis), accuracy from 49.6% (bone destruction) to 81.5% (synovitis), OR from 0.261 (soft-tissue mass) to 35.550 (synovitis). DATA CONCLUSION: Conventional MRI features have limited accuracy to differentiate septic and aseptic THA failure. Lymph nodal indices, particularly those related to nodal number, may represent biomarkers of THA infection. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY STAGE: 2.
BACKGROUND: Very little has been published about the diagnostic performance of MRI in total hip arthroplasty (THA) infection. PURPOSE: To determine the diagnostic performance of conventional MRI features and of new lymph nodal indices to identify infection in patients with failed THA. STUDY TYPE: Retrospective. POPULATION: In all, 119 patients (66 females; age 66.9 ± 12.4 years) with failed THA. FIELD STRENGTH/SEQUENCES: Metal artifact reduction sequence (MARS) protocol including short tau inversion recovery and turbo spin-echo T1 - and T2 -weighted sequences at 1.5T. ASSESSMENT: Patients underwent pelvis MRI prior to failed THA revision. MRIs were reviewed to identify periprosthetic bone destruction, soft-tissue mass, effusion, synovitis, lamellated synovitis, extracapsular edema, fibrous periprosthetic membrane, bone edema, and extracapsular collection/sinus tract. The number and maximum diameter of inguinal, obturator and iliac lymph nodes of the affected hip were assessed and normalized to those of the unaffected hip to calculate the ratio of nodal size (RNS), ratio of node number (RNN), difference of nodal size (DNS), and difference of node number (DNN). STATISTICAL TESTS: The Mann-Whitney U-and chi-square test were used. Diagnostic performance of indices and odds ratios (OR) were calculated. RESULTS: RNS, RNN, DNS, and DNN indices were significantly different (P = 0.000) between infected and noninfected THA, with accuracies ranging from 84.8% (RNS) and 93.1% (RNN). All other MRI features were significantly more prevalent in infected THA (P ≤ 0.002), except bone destruction, periarticular soft-tissue mass, and fibrous membrane (P ≥ 0.031). Sensitivities ranged from 7.9% (soft-tissue mass) to 76.3% (effusion/bone edema), specificity from 45.7% (bone destruction) to 97.5% (synovitis/lamellated synovitis), accuracy from 49.6% (bone destruction) to 81.5% (synovitis), OR from 0.261 (soft-tissue mass) to 35.550 (synovitis). DATA CONCLUSION: Conventional MRI features have limited accuracy to differentiate septic and aseptic THA failure. Lymph nodal indices, particularly those related to nodal number, may represent biomarkers of THA infection. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY STAGE: 2.
Authors: André Busch; Marcus Jäger; Sascha Beck; Alexander Wegner; Erik Portegys; Dennis Wassenaar; Jens Theysohn; Johannes Haubold Journal: BMC Musculoskelet Disord Date: 2022-06-28 Impact factor: 2.562