Normal hip joint fluid volumes in healthy children of different ages, based on MRI volumetric quantitative measurement

Postoperative Effusion-Synovitis is Associated With Poor Clinical Outcomes in Patients With Femoroacetabular Impingement Syndrome: a Consecutive Magnetic Resonance Imaging Study

PURPOSE

(1) to investigate the consecutive changes in effusion-synovitis following primary arthroscopic treatment for patients with femoroacetabular impingement syndrome (FAIS), and (2) to determine the effect of postoperative effusion-synovitis on clinical outcomes.

METHODS

Data between March 2021 and January 2022 was reviewed. Patients diagnosed with FAIS and undergoing hip arthroscopic treatment were included. Exclusion criteria were incomplete magnetic resonance imaging (MRI) data, prior history of hip surgery, labral reconstruction, and concomitant hip conditions. MRI (non-contrast 3.0 T) was performed preoperatively and 3, 6, 12-month postoperatively, and the measurement of the largest femoral neck fluid thickness (FTM) and cross-sectional area (CSA) of the effusion-synovitis were collected. Preoperative and a minimum of 2-year postoperative patient-reported outcome (PRO) scores including Visual Analog pain Scale (VAS), modified Harris Hip Score (mHHS), and international Hip Outcome Tool, 12-component form (iHOT-12) were collected and compared. Postoperative Tegner activity scale was also collected. The PROs and achievements of minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were compared between patients with and without postoperative effusion-synovitis. Multivariate linear regression analysis was performed to determine the effect of the effusion-synovitis size on PROs.

RESULTS

A total of 61 patients (61 hips) were included in the study. The 3-month postoperative FTM, CSA and grade of effusion-synovitis presented a significant increase compared to the preoperative values (all with P < .05). No significant differences were observed in the 6-month postoperative measurements compared to the preoperative values (all with P > .05). At the 12-month follow-up, although there was a significant decrease in all measurements compared to the preoperative values (all with P < .001), 39 patients (63.9%) still presented effusion-synovitis. Compared to the other 22 patients (36.1%) without effusion-synovitis, these patients presented inferior mHHS, iHOT-12 (all with P < .05), as well as lower achievement of PASS of mHHS (82.1% vs 100%, P = .035) and iHOT-12 (38.5% vs 81.8%, P = .001). The achievement of MCID of mHHS (79.5% vs 77.3%, P = .839) and iHOT-12 (89.7% vs 95.5%, P = .839) were comparable between patients with and without effusion-synovitis. The postoperative sagittal CSA (Beta = -.302, P = .039) were negatively related to mHHS in the regression analysis.

CONCLUSION

After arthroscopic treatment for FAIS, the level of effusion-synovitis presented an initial increase, then followed by a subsequent decrease. Effusion-synovitis was significantly alleviated at 12 months compared to the preoperative level. Patients with postoperative effusion-synovitis had inferior clinical outcomes and lower achievement of PASS compared to those without.

LEVEL OF EVIDENCE

Level IV; retrospective case series.

Automatic Assessment Of Hip Effusion From MRI

Joint effusion is a hallmark of osteoarthritis (OA) associated with stiffness, and may relate to pain, disability, and long-term outcomes. However, it is difficult to quantify accurately. We propose a new Deep Learning (DL) approach for automatic effusion assessment from Magnetic Resonance Imaging (MRI) using volumetric quantification measures (VQM). We developed a new multiplane ensemble convolutional neural network (CNN) approach for 1) localizing bony anatomy and 2) detecting effusion regions. CNNs were trained on femoral head and effusion regions manually segmented from 3856 images (63 patients). Upon validation on a non-overlapping set of 2040 images (34 patients) DL showed high agreement with ground-truth in terms of Dice score (0.85), sensitivity (0.86) and precision (0.83). Agreement of VQM per-patient was high for DL vs experts in term of Intraclass correlation coefficient (ICC)= 0.88[0.80,0.93]. We expect this technique to reduce inter-observer variability in effusion assessment, reducing expert time and potentially improving the quality of OA care.Clinical Relevance- Our technique for automatic assessment of hip MRI can be used for volumetric measurement of effusion. We expect this to reduce variability in OA biomarker assessment and provide more reliable indicators for disease progression.

Volumetric quantitative measurement of hip effusions by manual versus automated artificial intelligence techniques: An OMERACT preliminary validation study

OBJECTIVE

Preliminary assessment, via OMERACT filter, of manual and automated MRI hip effusion Volumetric Quantitative Measurement (VQM).

METHODS

For 358 hips (93 osteoarthritis subjects, bilateral, 2 time points), 2 radiologists performed manual VQM using custom Matlab software. A Mask R-CNN artificial-intelligence (AI) tool was trained to automatically compute joint fluid volumes.

RESULTS

Manual VQM had excellent inter-observer reliability (ICC 0.96). AI predicted hip fluid volumes with ICC 0.86 (status), 0.58 (change) vs. 2 human readers.

CONCLUSION

Hip joint fluid volumes are reliably assessed by VQM. It is feasible to automate this approach using AI, with promising initial reliability.