Publications by authors named "Hollis G Potter"

224 Publications

Clinical Feasibility of Multi-Acquisition Variable-Resonance Image Combination-Based T2 Mapping near Hip Arthroplasty.

HSS J 2021 Jul 25;17(2):165-173. Epub 2021 Feb 25.

MRI Laboratory, Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA.

Hip arthroplasty is increasingly prevalent, and early detection of complications can improve outcomes. Quantitative magnetic resonance imaging (qMRI) methods using multi-acquisition variable-resonance image combination (MAVRIC) may allow for the assessment of soft tissues in close proximity to hip arthroplasty devices. : We sought to determine the clinical feasibility of MAVRIC-based T2 mapping as a qMRI approach for assessing synovial reactions in patients with a hip arthroplasty device. We hypothesized that there would be differences in T2 metrics by synovial type, clinical impression, and clinical findings related to synovitis. : We conducted a cross-sectional study of 141 subjects with 171 hip arthroplasties with greater than 1 year post-implantation. We enrolled subjects who had had a primary total hip arthroplasty or hip resurfacing arthroplasty between May 2019 and March 2020, excluding those with a revision hip arthroplasty and those with standard safety contraindications for receiving an MRI. Institutional standard 2D fast spin echo (FSE), short-tau inversion recovery (STIR), and susceptibility-reduced MAVRIC morphological MR images were acquired for each hip and followed by a dual-echo acquisition MAVRIC T2 mapping sequence. : While 131 subjects (81%) were classified as having a "normal" synovial reaction, significantly longer T2 values were found for fluid synovial reactions compared with mixed reactions. In addition, subjects with synovial dehiscence and decompression present had T2 prolongation. Larger synovial volumes were found in subjects with low-signal intensity deposits. : MAVRIC-based T2 mapping is clinically feasible and there are significant quantitative differences based on type of synovial reaction. Patients undergoing hip arthroscopy revision surgery will warrant comparison of T2 values with direct histologic assessment of a tissue sample obtained intraoperatively. The approach used in this study may be used for a quantitative evaluation and monitoring of soft tissues around metal implants.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/1556331621994801DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8361595PMC
July 2021

Stretchable self-tuning MRI receive coils based on liquid metal technology (LiquiTune).

Sci Rep 2021 Aug 10;11(1):16228. Epub 2021 Aug 10.

Department of Radiology, Weill Cornell Medicine, New York, NY, 10065, USA.

Magnetic resonance imaging systems rely on signal detection via radiofrequency coil arrays which, ideally, need to provide both bendability and form-fitting stretchability to conform to the imaging volume. However, most commercial coils are rigid and of fixed size with a substantial mean offset distance of the coil from the anatomy, which compromises the spatial resolution and diagnostic image quality as well as patient comfort. Here, we propose a soft and stretchable receive coil concept based on liquid metal and ultra-stretchable polymer that conforms closely to a desired anatomy. Moreover, its smart geometry provides a self-tuning mechanism to maintain a stable resonance frequency over a wide range of elongation levels. Theoretical analysis and numerical simulations were experimentally confirmed and demonstrated that the proposed coil withstood the unwanted frequency detuning typically observed with other stretchable coils (0.4% for the proposed coil as compared to 4% for a comparable control coil). Moreover, the signal-to-noise ratio of the proposed coil increased by more than 60% as compared to a typical, rigid, commercial coil.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-95335-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8355233PMC
August 2021

Adverse Local Tissue Reactions are Common in Asymptomatic Individuals After Hip Resurfacing Arthroplasty: Interim Report from a Prospective Longitudinal Study.

Clin Orthop Relat Res 2021 07 7. Epub 2021 Jul 7.

MRI Research Laboratory, Hospital for Special Surgery, New York, NY, USA.

Background: The evaluation of the natural history prevalence of adverse local tissue reactions (ALTRs) using MRI has focused only on metal-on-metal (MoM) bearing surfaces without comparison to nonMoM bearing surfaces.

Questions/purposes: To determine (1) the longitudinal changes and differences in blood metal ion levels in patients with hip resurfacing arthroplasty (HRA), ceramic-on-ceramic (CoC) THA, and metal-on-polyethylene (MoP) THA compared with those undergoing ceramic-on-polyethylene (CoP) THA; (2) how the longitudinal change of synovial reaction classification in patients with HRA, CoC THA, and MoP THA compares with those undergoing CoP THA, and whether there is an association between the presence of an ALTR or metallosis on MRI with corresponding patient-reported outcomes, or the presence of capsular dehiscence; and (3) differences in blood metal ion levels between patients undergoing HRA with an ALTR or metallosis on MRI and those with HRA without these conditions.

Methods: Between March 2014 and February 2019, 22,723 patients underwent primary HRA and THA at one center. Patients received an HRA based on their desired athletic level after surgery and the presence of normal acetabular and proximal femoral bone morphology without osteopenia or osteoporosis. Two percent (342 of 22,723) of patients were contacted to participate, and 71% (243 of 342 hips in 206 patients) were enrolled for analysis at baseline. The patients underwent arthroplasty for degenerative joint disease, and 25 patients withdrew over the course of the study. We included patients who were more than 1 year postarthroplasty. All participants had an MRI examination and blood serum ion testing and completed a Hip Disability and Osteoarthritis Outcome Score survey annually for four years (baseline, year 1, year 2, year 3). Morphologic and susceptibility-reduced MR images were evaluated by a single radiologist not involved in the care of patients for the presence and classification of synovitis (Gwet AC1: 0.65 to 0.97), synovial thickness, and volume (coefficient of repeatability: 1.8 cm3). Linear mixed-effects models were used to compare the mean synovial thickness, synovial volume, and Hip Disability and Osteoarthritis Outcome Score subscales between bearing surfaces at each timepoint and within each bearing surface over time. Marginal Cox proportional hazards models were used to compare the time to and the risk of developing ALTR only, metallosis only, and ALTR or metallosis between bearing surfaces. All models were adjusted for age, sex, BMI, and length of implantation based on known confounders for hip arthroplasty. Adjustment for multiple comparisons was performed using the Dunnett-Hsu method.

Results: Patients with unilateral HRA had higher cobalt and chromium serum ion levels (baseline: 1.8 ± 0.8 ppb, year 1: 2.0 ± 1.5 ppb, year 2: 2.1 ± 1.2 ppb, year 3: 1.6 ± 0.7 ppb) than those with unilateral CoP bearings (baseline: 0.0 ± 0.1 ppb, year 1: 0.1 ± 0.3 ppb, year 2: 0.0 ± 0.2 ppb, year 3: 0.0 ± 0.0 ppb) at all timepoints (p < 0.001 for each time point). More patients who received an HRA developed ALTR or metallosis on MRI than did patients with CoP bearings (hazard ratio 4.8 [95% confidence interval 1.2 to 18.4]; p = 0.02). There was no association between the longitudinal change of synovial reaction to ALTR or metallosis on MRI with patient-reported outcomes. In addition, there was no association between the presence of dehiscence at baseline and the subsequent development of ALTR or metallosis, as seen on MRI. There were elevated cobalt (4.7 ± 3.5 ppb) and chromium (4.7 ± 2.6 ppb) serum levels in patients with unilateral HRA who had an ALTR or metallosis present on MRI at year 1 compared with patients without an ALTR or metallosis on MRI (cobalt: 1.8 ± 1.0 ppb, mean difference 4.7 ppb [95% CI 3.3 to 6.0]; p < 0.001; chromium: 2.3 ± 0.5 ppb, mean difference 3.6 ppb [95% CI 2.2 to 5.0]; p < 0.001) as well as for chromium at year 3 (3.9 ± 2.4 ppb versus 2.2 ± 1.1 ppb, mean difference 1.3 ppb [95% CI 0.3 to 2.4]; p = 0.01).

Conclusion: We found a higher proportion of ALTR or metallosis on MRI in patients with HRA compared with patients with CoP, even when patient self-assessed symptomatology of those with an ALTR or metallosis on MRI was not different than the absence of these features. MRI detected ALTRs in high-function patients, emphasizing that an annual clinical assessment dependent on survey or blood ion testing alone may not detect soft tissue complications. The results of this study are in line with prior consensus recommendations of using MRI as part of a routine follow-up protocol for this patient population.

Level Of Evidence: Level III, therapeutic study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/CORR.0000000000001882DOI Listing
July 2021

CORR Insights®: What Is the Best Way for Patients to Take Photographs of Medical Images (Radiographs, CT, and MRI) Using a Smartphone?

Authors:
Hollis G Potter

Clin Orthop Relat Res 2021 10;479(10):2236-2238

H. G. Potter, Chair, Department of Radiology and Imaging, Hospital for Special Surgery, Professor of Radiology, Weill Medical College of Cornell University, New York, NY, USA.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/CORR.0000000000001786DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8445551PMC
October 2021

Genicular Artery Embolization for Refractory Hemarthrosis following Total Knee Arthroplasty: Technique, Safety, Efficacy, and Patient-Reported Outcomes.

J Vasc Interv Radiol 2021 Aug 5;32(8):1128-1135. Epub 2021 May 5.

Department of Radiology, Division of Interventional Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.

Purpose: To investigate the safety and efficacy of genicular artery embolization for treatment of refractory hemarthrosis following total knee arthroplasty.

Material And Methods: Patients who underwent genicular artery embolization with spherical embolics between January 2010 and March 2020 at a single institution were included if they had undergone total knee arthroplasty and subsequently experienced recurrent hemarthrosis. Technical success was defined as the significant reduction or elimination of the hyperemic blush. Clinical success was defined as the absence of clinical evidence of further hemarthrosis. Clinical follow-up was performed 7-14 days after the procedure and at 3-month intervals thereafter via a telephone interview. A total of 117 embolizations, comprising 82 initial, 28 first repeat, and 7 second repeat, were performed.

Results: An average of 2.5 arteries was treated per procedure. The superior lateral genicular artery was the most frequently embolized. The most utilized embolic size was 100-300 μm. Follow-up was available for all patients, with a median duration of 21.5 months. 65.9%, 25.6%, and 8.5% of patients underwent 1, 2, and 3 treatments, respectively. Complications occurred following 12.8% of treatments, of which the most common was transient cutaneous ischemia. Technical success was achieved in all cases. Clinical success was achieved in 56%, 79%, and 85% of patients following the first, second, and third treatment, respectively. 83% of patients reported being either satisfied or very satisfied with the overall result.

Conclusions: Targeted genicular artery embolization with spherical embolics is an effective treatment for recurrent hemarthrosis with infrequent serious complications. Repeat embolization should be considered in cases of recurrence following initial therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jvir.2021.04.020DOI Listing
August 2021

Differences in the magnetic resonance imaging parameter T2* may be identified during the course of canine patellar tendon healing: a pilot study.

Quant Imaging Med Surg 2021 Apr;11(4):1234-1246

MRI Laboratory, Hospital for Special Surgery, New York, NY, USA.

Background: Previous studies have utilized ultrashort echo (UTE) magnetic resonance imaging (MRI), and derived T2* maps, to evaluate structures with highly ordered collagen structures such as tendon. T2* maps may provide a noninvasive means to assess tendon damage and healing. This pilot study evaluated the longitudinal relationship of an induced mechanical strain on the patellar tendon with corresponding UTE T2* metrics, histologic and biomechanical evaluation at two post-operative time points.

Methods: A total of 27 patellar tendons in male Beagles were surgically subjected to stretching by a small diameter (SmD) or a large diameter (LgD) diameter rod to induce damage due to strain, and evaluated at 4- and 8-week intervals using quantitative MRI (qMRI), biomechanical testing, and histology. A separate set of 16 limbs were used as controls.

Results: The tendons experienced a 67% and 17% prolongation of short T2* values as compared to controls at 4 and 8 weeks post-operatively, respectively. Histologic analysis displayed a trend of increased collagen disruption at 4 weeks followed by presence of greater organization at 8 weeks. Biomechanical evaluation found a reduction of tendon modulus and failure strain at both time points, and an increase in cross-sectional area at 4 weeks as compared to controls.

Conclusions: These findings display tendon healing in response to an imposed strain and present the utility of qMRI to evaluate longitudinal differences of patellar tendon T2* values in a model of induced subclinical tendon damage. The qMRI technique of UTE provides a means to non-invasively evaluate the healing process of a mechanically damaged tendon.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/qims-20-684DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7930665PMC
April 2021

Knee cartilage T relaxation times 3 months after ACL reconstruction are associated with knee gait variables linked to knee osteoarthritis.

J Orthop Res 2021 Mar 30. Epub 2021 Mar 30.

Department of Mechanical Engineering, University of Delaware, Newark, Delaware, USA.

Osteoarthritis development after ACL reconstruction (ACLR) is not well understood. Investigators have examined associations between knee biomechanical alterations and quantitative MRI (qMRI) variables, reflective of cartilage health, 12-60 months following ACLR; however, none have done so early after surgery. As part of an exploratory study, 45 individuals (age, 23 ± 7 years) underwent motion analysis during walking and qMRI 3 months after ACLR. For each limb, peak knee adduction moment (pKAM) and peak knee flexion moment (pKFM) were determined using inverse dynamics and peak medial compartment force was calculated using a neuromusculoskeletal model. T relaxation times in the medial compartment and linear regressions were used to determine the associations between gait variables and deep and superficial cartilage T relaxation times in six regions. pKAM was positively associated with deep layer T relaxation times within the femoral central and posterior regions when examined in the involved limb and from an interlimb difference perspective (involved limb - uninvolved limb). After adjusting for age, the association between interlimb difference of pKAM and interlimb difference of deep layer T relaxation times in the tibial central region became significant (p = .043). Interlimb difference of pKFM was negatively associated with interlimb difference of deep layer T relaxation times within the femoral central and posterior regions. These associations suggest that degenerative pathways leading to osteoarthritis may be detectable as early as 3 months after reconstruction. Preventative therapeutic techniques may need to be employed early in the rehabilitation process to prevent cartilage degradation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jor.25043DOI Listing
March 2021

Effects of the Competitive Season and Off-Season on Knee Articular Cartilage in Collegiate Basketball Players Using Quantitative MRI: A Multicenter Study.

J Magn Reson Imaging 2021 09 24;54(3):840-851. Epub 2021 Mar 24.

Department of Radiology, Stanford University, Stanford, California, USA.

Background: Injuries to the articular cartilage in the knee are common in jumping athletes, particularly high-level basketball players. Unfortunately, these are often diagnosed at a late stage of the disease process, after tissue loss has already occurred.

Purpose/hypothesis: To evaluate longitudinal changes in knee articular cartilage and knee function in National Collegiate Athletic Association (NCAA) basketball players and their evolution over the competitive season and off-season.

Study Type: Longitudinal, multisite cohort study.

Population: Thirty-two NCAA Division 1 athletes: 22 basketball players and 10 swimmers.

Field Strength/sequence: Bilateral magnetic resonance imaging (MRI) using a combined T and T magnetization-prepared angle-modulated portioned k-space spoiled gradient-echo snapshots (MAPSS) sequence at 3T.

Assessment: We calculated T and T relaxation times to compare compositional cartilage changes between three timepoints: preseason 1, postseason 1, and preseason 2. Knee Osteoarthritis Outcome Scores (KOOS) were used to assess knee health.

Statistical Tests: One-way variance model hypothesis test, general linear model, and chi-squared test.

Results: In the femoral articular cartilage of all athletes, we saw a global decrease in T and T relaxation times during the competitive season (all P < 0.05) and an increase in T and T relaxation times during the off-season (all P < 0.05). In the basketball players' femoral cartilage, the anterior and central compartments respectively had the highest T and T relaxation times following the competitive season and off-season. The basketball players had significantly lower KOOS measures in every domain compared with the swimmers: Pain (P < 0.05), Symptoms (P < 0.05), Function in Daily Living (P < 0.05), Function in Sport/Recreation (P < 0.05), and Quality of Life (P < 0.05).

Conclusion: Our results indicate that T and T MRI can detect significant seasonal changes in the articular cartilage of basketball players and that there are regional differences in the articular cartilage that are indicative of basketball-specific stress on the femoral cartilage. This study demonstrates the potential of quantitative MRI to monitor global and regional cartilage health in athletes at risk of developing cartilage problems.

Level Of Evidence: 2 Technical Efficacy Stage: 2.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jmri.27610DOI Listing
September 2021

MRI Visualization of Polyethylene Post Fractures in Posterior Stabilized Total Knee Arthroplasty.

AJR Am J Roentgenol 2021 Oct 24;217(4):957-958. Epub 2021 Mar 24.

Department of Radiology and Imaging, Hospital for Special Surgery, 535 E 70th St, New York, NY 10021.

Polyethylene post fracture is a recognized complication of posterior stabilized total knee arthroplasty. Two radiologists retrospectively reviewed MRI examinations of 19 reported post fractures in 18 patients; all fractures were subsequently confirmed surgically with no false-positive cases. All post fractures were visualized as a combination of post deformity and signal-void fragment in a joint recess. A metal artifact reduction 3D multispectral imaging sequence improved fracture visualization versus conventional sequences in 47% of cases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2214/AJR.21.25669DOI Listing
October 2021

Improved nerve conspicuity with water-weighting and denoising in two-point Dixon magnetic resonance neurography.

Magn Reson Imaging 2021 06 20;79:103-111. Epub 2021 Mar 20.

Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA.

Background: T-weighted, two-point Dixon fast-spin-echo (FSE) is an effective technique for magnetic resonance neurography (MRN) that can provide quantitative assessment of muscle denervation. Low signal-to-noise ratio and inadequate fat suppression, however, can impede accurate interpretation.

Purpose: To quantify effects of principal component analysis (PCA) denoising on tissue signal intensities and fat fraction (FF) and to determine qualitative image quality improvements from both denoising and water-weighting (WW) algorithms to improve nerve conspicuity and fat suppression.

Study Type: Prospective.

Subjects: Twenty-one subjects undergoing MR neurography evaluation (11/10 male/female, mean age = 46.3±13.7 years) with 60 image volumes. Twelve subjects (23 image volumes) were determined to have muscle denervation based on diffusely elevated T signal intensity.

Field Strength/sequence: 3 T, 2D, two-point Dixon FSE.

Assessment: Qualitative assessment included overall image quality, nerve conspicuity, fat suppression, pulsation and ringing artifacts by 3 radiologists separately on a three-point scale (1 = poor, 2 = average, 3 = excellent). Quantitative measurements for FF and signal intensity relative to normal muscle were made for nerve, abnormal muscle and subcutaneous fat.

Statistical Tests: Linear and ordinal regression models were used for quantitative and qualitative comparisons, respectively; 95% confidence intervals (CIs) and p-values for pairwise comparisons were adjusted using the Holm-Bonferroni method. Inter-rater agreement was assessed using Gwet's agreement coefficient (AC).

Results: Simulations showed PCA-denoising reduced FF error from 2.0% to 1.0%, and from 7.6% to 3.1% at noise levels of 10% and 30%, respectively. In human subjects, PCA-denoising did not change signal levels and FF quantitatively. WW decreased fat signal significantly (-83.6%, p < 0.001). Nerve conspicuity was improved by WW (odds ratio, OR = 5.8, p < 0.001). Fat suppression was improved by both PCA (OR = 3.6, p < 0.001) and WW (OR = 2.2, p < 0.001). Overall image quality was improved by PCA + WW (OR = 1.7, p = 0.04).

Conclusions: WW and PCA-denoising improved nerve conspicuity and fat suppression in MR neurography. Denoising can potentially provide improved accuracy of FF maps for assessing fat-infiltrated muscle.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mri.2021.03.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8107136PMC
June 2021

CORR Insights®: What Is the Correlation Among dGEMRIC, T1p, and T2* Quantitative MRI Cartilage Mapping Techniques in Developmental Hip Dysplasia?

Authors:
Hollis G Potter

Clin Orthop Relat Res 2021 05;479(5):1025-1027

H. G. Potter, Chairman, Department of Radiology and Imaging, Professor of Radiology, Hospital for Special Surgery, New York, NY, USA.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/CORR.0000000000001645DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8083799PMC
May 2021

Pre-operative Static Anterior Tibial Translation Assessed on MRI Does Not Influence Return to Sport or Satisfaction After Anterior Cruciate Ligament Reconstruction.

HSS J 2020 Dec 17;16(Suppl 2):475-481. Epub 2019 Oct 17.

Hospital for Special Surgery, 535 E. 70th St., New York, NY 10021 USA.

Background: It has been suggested that the degree of anterior tibial translation (ATT) as measured passively on imaging studies (static ATT) after an anterior cruciate ligament (ACL) injury may influence outcomes after ACL reconstruction. However, there is a lack of evidence supporting these suggestions.

Questions/purposes: The purpose of this retrospective prognostic study was to assess the predictive value of pre-operative static ATT in knees with ACL injury on return to sport and in satisfaction after ACL reconstruction. Our hypothesis was that greater static ATT would be associated with lower rates of return to sport and lower levels of satisfaction.

Methods: Patients treated with ACL reconstruction were identified from an institutional registry and assigned to one of three groups according to their ACL injury type: acute ACL injury, chronic ACL injury, and failed ACL reconstruction. ATT in each knee compartment was measured using magnetic resonance imaging, and a retrospective telephone questionnaire was used to investigate post-ACL reconstruction return to sport and subjects' satisfaction.

Results: One hundred thirty patients (52 acute with ACL injury, 29 with chronic ACL injury, and 49 with failed ACL reconstruction) completed the questionnaire, with a mean follow-up of 5.67 years. Ninety-seven patients (74.6%) returned to their primary sport, of whom 63 (65%) returned to the same level of sport. The mean time to return to sport was 10.1 months (range, 2 to 24 months). Overall, 113 patients (87%) were either very satisfied or satisfied with their outcomes. No difference in medial or lateral ATT was found between patients who returned to sport and those who did not. The failed-ACL reconstruction group had significantly lower rates of return to sport than did acutely and chronically injured patients (60.4% versus 88.5% and 75.9%, respectively).

Conclusion: The degree of pre-operative ATT in an ACL-deficient knee was not correlated with return to sport or satisfaction after ACL reconstruction. In this study cohort, only failed-ACL reconstruction patients undergoing revision ACL reconstruction were significantly less likely to return to their main sport. They were also less likely to return to sport at their pre-operative level, if they did return to sport.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11420-019-09724-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7749907PMC
December 2020

Assessment of a deep-learning system for fracture detection in musculoskeletal radiographs.

NPJ Digit Med 2020 30;3:144. Epub 2020 Oct 30.

Imagen Technologies, Inc., 151 West 26th Street, Suite 1001, New York, NY 10001 USA.

Missed fractures are the most common diagnostic error in emergency departments and can lead to treatment delays and long-term disability. Here we show through a multi-site study that a deep-learning system can accurately identify fractures throughout the adult musculoskeletal system. This approach may have the potential to reduce future diagnostic errors in radiograph interpretation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41746-020-00352-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7599208PMC
October 2020

Clinical outcomes and reoperation rates of stable and unstable ramp lesions in the setting of ACL rupture.

Knee Surg Sports Traumatol Arthrosc 2020 12 10;28(12):4034-4036. Epub 2020 Oct 10.

Sports Medicine and Shoulder Service, Hospital for Special Surgery, New York, USA.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00167-020-06315-8DOI Listing
December 2020

Multiacquisition Variable-Resonance Image Combination Magnetic Resonance Imaging Used to Study Detailed Bone Apposition and Fixation of an Additively Manufactured Cementless Acetabular Shell.

Arthroplast Today 2020 Dec 26;6(4):694-698. Epub 2020 Aug 26.

Department of Orthopedic Surgery, Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, NY, USA.

Background: The ability to utilize magnetic resonance imaging (MRI) to assess bony fixation in 3 dimensions may allow a better understanding of the implant design and bony integration. We hypothesized that a new 3-dimensionally printed cementless highly porous acetabular component (Stryker Trident II Tritanium) would show better fixation than an earlier cup from the same manufacturer as assessed by the noninvasive technique of multispectral MRI.

Methods: Multiacquisition variable-resonance image combination selective metal suppression MRI was performed in 19 patients implanted with a new 3-dimensionally printed cup and 20 patients who had received a previous-generation cup from the same manufacturer at 1-year follow-up. Each cup was graded globally as well as by 9 specific zones. Integration grades were performed for each zone: 0, full bone integration; 1, fibrous membrane present; 2, osteolysis; and 3, fluid present. A mixed-effects logistic regression model was used to compare fixation between the 2 groups.

Results: All cups in both cohorts showed greater than 90% estimated global bony integration (3-dimensionally printed cups, 99.4%; regular cups 91.6%) with no osteolysis or fluid observed in any cup. The 3-dimensionally printed cup had 1 of 171 zones (0.6%) graded as fibrous membrane present, while the 2-dimensional group had 15 of 180 zones (8.3%) graded as fibrous. Of note, screw hole regions were omitted but may be read as fibrous membrane areas.

Conclusion: Using multiacquisition variable-resonance image combination selective MRI, our analysis showed greater osteointegration and less fibrous membrane formation in the 3-dimensionally printed cups than the control group at 1-year follow-up.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.artd.2020.07.019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7475047PMC
December 2020

Multiparametric MRI characterization of knee articular cartilage and subchondral bone shape in collegiate basketball players.

J Orthop Res 2021 07 17;39(7):1512-1522. Epub 2020 Sep 17.

Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.

Magnetic resonance imaging (MRI) is commonly used to evaluate the morphology of the knee in athletes with high-knee impact; however, complex repeated loading of the joint can lead to biochemical and structural degeneration that occurs before visible morphological changes. In this study, we utilized multiparametric quantitative MRI to compare morphology and composition of articular cartilage and subchondral bone shape between young athletes with high-knee impact (basketball players; n = 40) and non-knee impact (swimmers; n = 25). We implemented voxel-based relaxometry to register all cases to a single reference space and performed a localized compositional analysis of T - and T -relaxation times on a voxel-by-voxel basis. Additionally, statistical shape modeling was employed to extract differences in subchondral bone shape between the two groups. Evaluation of cartilage composition demonstrated a significant prolongation of relaxation times in the medial femoral and tibial compartments and in the posterolateral femur of basketball players in comparison to relaxation times in the same cartilage compartments of swimmers. The compositional analysis also showed depth-dependent differences with prolongation of the superficial layer in basketball players. For subchondral bone shape, three total modes were found to be significantly different between groups and related to the relative sizes of the tibial plateaus, intercondylar eminences, and the curvature and concavity of the patellar lateral facet. In summary, this study identified several characteristics associated with a high-knee impact which may expand our understanding of local degenerative patterns in this population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jor.24851DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8359246PMC
July 2021

Non-treatment of stable ramp lesions does not degrade clinical outcomes in the setting of primary ACL reconstruction.

Knee Surg Sports Traumatol Arthrosc 2020 Nov 1;28(11):3576-3586. Epub 2020 May 1.

Sports Medicine and Shoulder Service, Hospital for Special Surgery, New York, NY, USA.

Purpose: The purpose of this study was to evaluate the clinical outcomes of various methods of treatment of stable and unstable ramp lesions compared to patients with no meniscal pathology at the time of primary ACL reconstruction.

Methods: All patients with a preoperative MRI performed at our facility who were enrolled in an institutional ACL registry and 1-year clinical follow-up were identified. A musculoskeletal radiologist reviewed preoperative MRI scans for evidence of a ramp lesion. Ramp lesions were classified as stable if a peripheral tear of the posterior horn of the medial meniscus was identified by MRI, but did not displace into the medial compartment with anteriorly directed probing at the time of surgery. Ramp lesions were classified as unstable if a tear was identified by preoperative MRI at the meniscocapsular junction and the meniscus was displaceable into the medial compartment with probing. Reoperation rates for ACL graft failure or recurrent medial meniscus pathology were collected. Patient-reported outcome scores (IKDC, SF12 PCS, SF12 MCS, and Marx Activity scale) were recorded at baseline and final follow-up.

Results: A total of 162 patients were included in the analysis with median 2-year (range 1-5 years) clinical follow-up. Patients with a repaired unstable ramp lesion had a significantly higher likelihood of reoperation for recurrent medial meniscus pathology than patients without meniscal pathology at the time of index surgery. Patients with an untreated stable ramp lesion had a similar rate of reoperation when compared to patients without meniscal pathology. At final follow-up, there was no difference between groups in IKDC score, SF12 PCS/MCS, or Marx activity score or change in any score.

Conclusions: Patients with untreated stable ramp lesions have similar clinical outcomes at median 2-year (range 1-5 years) follow-up when compared to patients without a ramp lesion. Treatment of stable ramp lesions at the time of ACL reconstruction does not have clinical benefit.

Level Of Evidence: III.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00167-020-06017-1DOI Listing
November 2020

Multivariate use of MRI biomarkers to classify histologically confirmed necrosis in symptomatic total hip arthroplasty.

J Orthop Res 2020 07 23;38(7):1506-1514. Epub 2020 Mar 23.

Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin.

The failure of total hip arthroplasty (THA) is commonly associated with the necrosis of the periprosthetic tissue. To date, there is no established method to noninvasively quantify the progression of such necrosis. Magnetic resonance imaging (MRI) of soft tissues near implants has undergone a recent renaissance due to the development of multispectral metal-artifact reduction techniques. Advanced analysis of multispectral MRI has been shown capable of detecting small magnetism effects of metallic debris in periprosthetic tissue. The purpose of this study is to demonstrate the diagnostic utility of these MRI-based tissue-magnetism signatures. Together with morphological MRI metrics, such as synovial volume and thickness, these measurements are utilized as biomarkers to noninvasively detect soft-tissue necrosis in symptomatic THA patients ( ). All subjects underwent an advanced MRI scan before revision surgery and tissue biopsies utilized for necrosis grading. Statistical analyses demonstrated a weak, but significant positive correlation (P = .04) between MRI magnetism signatures and necrosis scores, while indicating no meaningful association between the latter and serum cobalt and chromium ion levels. Receiver-operating characteristic (ROC) analyses were then performed based on uni- and multivariate logistic regression models utilizing the measured MRI biomarkers as predictors of severe necrosis. The area under the curve of the ROC plots for MRI biomarkers as combined predictors were found to be 0.70 and 0.84 for cross-validation and precision-recall tests, respectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jor.24654DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8100875PMC
July 2020

Understanding the undulating pattern of the distal femoral growth plate: Implications for surgical procedures involving the pediatric knee: A descriptive MRI study.

Knee 2020 Mar 29;27(2):315-323. Epub 2020 Feb 29.

Hospital for Special Surgery, Weill Cornell Medical University, Department of Pediatric Orthopedic Surgery, 535 East 70th Street, New York, NY 10021, United States of America. Electronic address:

Introduction: Operative procedures near the distal femoral physis can result in iatrogenic damage if one is not familiar with the complex anatomy of the growth plate. The purpose of this study was to use physeal-specific MRI sequences to delineate the anatomic dimensions of the distal femoral physis.

Materials And Methods: Sixty patients underwent physeal-specific spoiled gradient 3-D fat saturated (SPGR) MRI analysis of a single knee. Three age groups (eight to 10, 11-13, and 14-16 years) comprised of equal numbers (n = 20) of boys and girls were evaluated. Using the SPGR coronal sequence, the distance of the physis to the femoral articular cartilage was recorded at the medial, mid-medial, notch, mid-lateral and lateral margins of the knee. Coronal measurements were recorded at four locations along the sagittal sequence, as the anteroposterior dimension of the knee was divided into equal quartiles.

Results: While little variation in shape was observed in the anterior quartile, the remaining quartiles demonstrated significant variability that increased moving posteriorly (p < .001), therefore reflecting a more concave shape in the posterior aspect of the femur. These observations were statistically significant for age at the posterior two quartiles.

Conclusion: These MRI data suggest that while the physis is linear in the anterior part of the femur, it possesses a more concave shape in the posterior aspect of the medial and lateral condyles. Findings were preserved across gender and age. Ultimately, these data can aid in preoperative planning and should be considered when performing operative procedures in the skeletally immature knee.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.knee.2020.02.003DOI Listing
March 2020

Synthetic Biphasic Scaffolds versus Microfracture for Articular Cartilage Defects of the Knee: A Retrospective Comparative Study.

Cartilage 2020 Feb 11:1947603520903418. Epub 2020 Feb 11.

Sports Medicine Service, Hospital for Special Surgery, New York, NY, USA.

Objective: The purpose of this study was to compare the results of a biphasic synthetic scaffold (TruFit, Smith & Nephew) to microfracture for the treatment of knee cartilage defects and identify patient- and lesion-specific factors that influence outcomes.

Design: Prospectively collected data from 132 patients (mean age, 41.8 years; 69% male) with isolated chondral or osteochondral femoral defects treated with biphasic synthetic scaffolds ( = 66) or microfracture ( = 66) were reviewed. Clinical outcomes were evaluated longitudinally over 5 years with the Short Form-36 (SF-36), Activities of Daily Living of the Knee Outcome Survey (KOS-ADL), International Knee Documentation Committee (IKDC), and Marx Activity Scale. Cartilage-sensitive magnetic resonance imaging (MRI) was performed to evaluate osseous integration and cartilage fill in a subgroup of patients. Multivariate regression analysis was used to identify predictors of clinical outcomes within the scaffold group.

Results: Both groups demonstrated clinically significant improvements in knee clinical scores over 5 years ( < 0.01). There were no significant differences in KOS-ADL and IKDC scores between groups up to 5 years postoperatively. Marx activity level scores in the microfracture group declined over time, while significant improvements in activity level scores were observed in the scaffold group over 5 years ( < 0.01). Good-quality tissue fill and cartilage isointensity were more often observed in the scaffold group compared with the microfracture group, particularly with longer time intervals. Increasing age, high body mass index, prior microfracture, and traumatic etiology were predictors for inferior outcomes in the scaffold group.

Conclusions: Activity level and MRI appearance following treatment of cartilage lesions with the biphasic synthetic scaffold were superior to microfracture over time in this nonrandomized, retrospective comparison.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/1947603520903418DOI Listing
February 2020

How Useful Is Magnetic Resonance Imaging in Evaluating Adverse Local Tissue Reaction?

J Arthroplasty 2020 06 15;35(6S):S63-S67. Epub 2020 Jan 15.

Department of Radiology, Hospital for Special Surgery, New York, NY.

Biologic failures of hip arthroplasty have emerged as an increasing threat to the longevity of the prosthesis. While wear of modern-day bearings has been greatly reduced with the advent of cross-linked polyethylene, local reaction to metal particles either from the bearing itself or to any of the modular tapers appears to be on the rise. Monitoring of these reactions by the use of plain radiographs or serum markers appears to be insufficient to gauge the gravity of the response. Over the past decade, the use of magnetic resonance imaging (MRI) techniques has emerged as the superior noninvasive instrument to assess the extent of soft tissue reaction around hip implants. The use of MRI around implants was initially challenging due to the presence of relatively high ferrous metals especially cobalt which causes local distortion of the magnetic fields. Novel changes in pulse sequencing have greatly improved the sensitivity and specificity of MRI so that at this time, MR is the most predictive diagnostic tool in evaluating the extent of tissue destruction. We feel strongly that modern MRI techniques are the most important tool in the workup of the patient suspected of having an adverse tissue reaction after hip arthroplasty.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.arth.2020.01.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7239755PMC
June 2020

Clinical magnetic resonance imaging of arthroplasty at 1.5 T.

J Orthop Res 2020 07 4;38(7):1455-1464. Epub 2020 Feb 4.

Department of Radiology and Imaging, Hospital for Special Surgery, New York, New York.

Magnetic resonance imaging (MRI) has historically been avoided for the routine clinical evaluation of metal implants at many clinical centers due to the presence of artifact that creates in-plane and through-plane distortions and signal intensity voids in generated images. However, when the image acquisition parameters are appropriately modified and advanced multi-spectral pulse sequences are used, high-quality diagnostic images can be generated and may be used for diagnosing patients with suspected periprosthetic pathology. MRI provides superior soft-tissue contrast and excellent sensitivity for mobile water and is, therefore, a valuable tool in the evaluation of these patients, given the increasing prevalence of arthroplasty within the general population. Knowledge of expected normal postoperative appearance in patients with total hip arthroplasty, total knee arthroplasty, and total shoulder arthroplasty facilitates the detection of abnormal findings in this population, as does familiarity with common pathologic conditions encountered in the periprosthetic region. This review article will provide background information regarding the presence of image artifacts, methods to reduce the artifacts, and application of MRI at 1.5 T for evaluating common complications in subjects with total knee arthroplasty, total hip arthroplasty, and total shoulder arthroplasty.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jor.24606DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7293946PMC
July 2020

Evaluation of Osseous Morphology of the Hip Using Zero Echo Time Magnetic Resonance Imaging.

Am J Sports Med 2019 12 21;47(14):3460-3468. Epub 2019 Oct 21.

Department of Radiology and Imaging, Hospital for Special Surgery, New York, New York, USA.

Background: Femoroacetabular impingement syndrome (FAIS) is a common disorder of the hip resulting in groin pain and ultimately osteoarthritis. Radiologic assessment of FAI morphologies, which may present with overlapping radiologic features of hip dysplasia, often requires the use of computed tomography (CT) for evaluation of osseous abnormality, owing to the difficulty of direct visualization of cortical and subchondral bone with conventional magnetic resonance imaging (MRI). The use of a zero echo time (ZTE) MRI pulse sequence may obviate the need for CT by rendering bone directly from MRI.

Purpose/hypothesis: The purpose was to explore the application of ZTE MRI to the assessment of osseous FAI and dysplasia morphologies of the hip. It was hypothesized that angular measurements from ZTE images would show significant agreement with measurements obtained from CT images.

Study Design: Cohort study (diagnosis); Level of evidence, 2.

Methods: Thirty-eight hips from 23 patients were imaged with ZTE MRI and CT. Clinically relevant angular measurements of hip morphology were made in both modalities and compared to assess agreement. Measurements included coronal and sagittal center-edge angles, femoral neck-shaft angle, acetabular version (at 1-, 2-, and 3-o'clock positions), Tönnis angle, alpha angle, and modified-beta angle. Interrater agreement was assessed for a subset of 10 hips by 2 raters. Intermodal agreement was assessed on the complete cohort and a single rater.

Results: Interrater agreement was demonstrated in both CT and ZTE, with intraclass correlation coefficient values ranging from 0.636 to 0.990 for ZTE and 0.747 to 0.983 for CT, indicating "good" to "excellent" agreement. Intermodal agreement was also shown to be significant, with intraclass correlation coefficients ranging from 0.618 to 0.904.

Conclusion: Significant agreement of angular measurements for hip morphology exists between ZTE MRI and CT imaging. ZTE MRI may be an effective method to quantitatively evaluate osseous hip morphology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/0363546519878170DOI Listing
December 2019

Nonoperative Treatment of Elbow Ulnar Collateral Ligament Injuries With and Without Platelet-Rich Plasma in Professional Baseball Players: A Comparative and Matched Cohort Analysis.

Am J Sports Med 2019 11 7;47(13):3107-3119. Epub 2019 Oct 7.

Investigation performed at Division of Sports Medicine, Department of Orthopaedic Surgery, Scripps Clinic, La Jolla, California, USA.

Background: Recent studies evaluating nonoperative treatment of elbow ulnar collateral ligament (UCL) injuries augmented with platelet-rich plasma (PRP) have shown promising results. To date, no comparative studies have been performed on professional baseball players who have undergone nonoperative treatment with or without PRP injections for UCL injuries.

Hypothesis: Players who received PRP injections would have better outcomes than those who did not receive PRP.

Study Design: Cohort study; Level of evidence, 3.

Methods: The Major League Baseball (MLB) Health and Injury Tracking System identified 544 professional baseball players who were treated nonoperatively for elbow UCL injuries between 2011 and 2015. Of these, 133 received PRP injections (PRP group) before starting their nonoperative treatment program, and 411 did not (no-PRP group). Player outcomes and a Kaplan-Meier survival analysis were compared between groups. In addition, to reduce selection bias, a 1:1 matched comparison of the PRP group versus the no-PRP group was performed. Players were matched by age, position, throwing side, and league status: major (MLB) and minor (Minor League Baseball [MiLB]). A single radiologist with extensive experience in magnetic resonance imaging (MRI) interpretation of elbow injuries in elite athletes analyzed 243 MRI scans for which images were accessible for tear location and grade interpretation.

Results: Nonoperative treatment of UCL injuries resulted in an overall 54% rate of return to play (RTP). Players who received PRP had a significantly longer delay in return to throwing ( < .001) and RTP ( = .012). The matched cohort analysis showed that MLB and MiLB pitchers in the no-PRP group had a significantly faster return to throwing ( < .05) and the MiLB pitchers in the no-PRP group had a significantly faster RTP ( = .045). The survival analysis did not reveal significant differences between groups over time. The use of PRP, MRI grade, and tear location were not statistically significant predictors for RTP or progression to surgery.

Conclusion: In this retrospective matched comparison of MLB and MiLB pitchers and position players treated nonoperatively for a UCL tear, PRP did not improve RTP outcomes or ligament survivorship, although there was variability with respect to PRP preparations, injection protocols, time from injury to injection, and rehabilitation programs. MRI grade and tear location also did not significantly affect RTP outcomes or progression to surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/0363546519876305DOI Listing
November 2019

Erratum to: What is the Diagnostic Accuracy of MRI for Component Loosening in THA?

Clin Orthop Relat Res 2019 Oct;477(10):2387

A.J. Burge, G.P. Konin, J.L. Berkowitz, B. Lin, M.F. Koff, H.G. Potter, Departments of Radiology and Imaging, Biostatistics, and MRI Laboratory, Hospital for Special Surgery, New York, NY, USA.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/CORR.0000000000000920DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6999940PMC
October 2019

Magnetic Resonance Imaging Grading System for Tears of the Latissimus Dorsi and Teres Major.

Orthop J Sports Med 2019 Mar 4;7(3):2325967119826548. Epub 2019 Mar 4.

Hospital for Special Surgery, New York, New York, USA.

Background: Recent awareness of latissimus dorsi/teres major (LD/TM) injuries has led to an increase in diagnoses. No magnetic resonance imaging (MRI) classification system specific to the LD/TM exists, nor has tear severity been correlated with ability to return to sport (RTS).

Purpose/hypothesis: The purpose of this study was to report a novel MRI classification system for LD/TM tears as well as to correlate tear grade with performance and RTS. We hypothesized that the new MRI classification system would have high intra- and interobserver reliabilities and that players with higher grade tears would require operative management.

Study Design: Cohort study (diagnosis); Level of evidence, 3.

Methods: All patients with LD/TM tears diagnosed by MRI who were under the care of 2 orthopaedic surgeons were included. On 2 occasions 60 days apart, MRIs were reviewed and graded by 2 authors using a new classification system. Intra- and interobserver reliabilities were calculated. Timing from injury to RTS was recorded, and performance upon RTS was analyzed.

Results: The proposed grading system had excellent intra- and interrater reliabilities (Cohen kappa >0.850). A total of 20 male patients (mean ± SD age, 26 ± 9.3 years) with LD/TM tears were included (80% were baseball pitchers). Of the 16 players treated operatively, 5 were initially treated nonoperatively by an outside physician but could not RTS (all professional baseball pitchers); 2 of these players had grade IIIA tears and 3 of the players had grade IVA tears. Regardless of initial treatment, ultimately 100% of the professional baseball players were able to RTS at a mean of 8.7 ± 3.3 months, although the initial nonoperative management failed for some of these players and they needed surgical intervention. No statistically significant differences were found between pre- versus postoperative performance in those professional players who were treated surgically.

Conclusion: The proposed MRI-based grading system for LD/TM tears had excellent reliability. This system may allow physicians to better advise patients and all involved health care providers. Consideration should be given to acutely treat grade III and IV tears with operative repair.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/2325967119826548DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6700928PMC
March 2019

MRI of Hip Arthroplasties: Comparison of Isotropic Multiacquisition Variable-Resonance Image Combination Selective (MAVRIC SL) Acquisitions With a Conventional MAVRIC SL Acquisition.

AJR Am J Roentgenol 2019 12 15;213(6):W277-W286. Epub 2019 Aug 15.

Department of Radiology and Imaging, Hospital for Special Surgery, 535 E 70th St, New York, NY 10021.

The objective of our study was to compare the quality and diagnostic utility of the following three metal artifact reduction sequences in evaluating hip arthroplasties: conventional multiacquisition variable-resonance image combination selective (MAVRIC SL), isotropic MAVRIC SL, and reduced-TR isotropic MAVRIC SL. Ninety-three hip arthroplasties (85 total hip replacements and eight hip resurfacings [nine bilateral hips]) in 84 patients (38 men and 46 women; mean age ± SD, 69.1 ± 9.7 years old) were imaged and evaluated. A calibration scan determined the number of spectral bins needed for each implant, and isotropic and conventional MAVRIC SL images were acquired. Reduced-TR isotropic MAVRIC SL scans were acquired for 40 arthroplasties. Two board-certified radiologists blinded to MRI acquisition evaluated images for clinical and image quality features and compared images using a mixed-effects ordinal logistic regression model and odds ratios. Rater agreement was assessed with Gwet agreement coefficients. Scanning times were compared using mixed-effects linear regression. Significance was set at < 0.05. Calibration scans decreased the number of bins needed (median, 12 bins; interquartile range, 10-16 bins). Isotropic MAVRIC SL (mean scanning time, 7 minutes 16 seconds; 95% CI, 7 minutes 7 seconds-7 minutes 25 seconds) acquisitions had the longest scanning time, and conventional (mean, 5 minutes 46 seconds; 95% CI, 5 minutes 37 seconds-5 minutes 55 seconds) and reduced-TR isotropic (5 minutes 28 seconds; 95% CI, 5 minutes 15 seconds-5 minutes 41 seconds) MAVRIC SL acquisitions had scanning times that were similar. Both isotropic and reduced-TR isotropic MAVRIC SL images showed decreased blurring and improved visualization of the synovium and periprosthetic bone compared with conventional MAVRIC SL images ( < 0.001). Isotropic MAVRIC SL acquisitions more effectively improved signal-to-noise ratio (SNR), visualization of the synovium and periprosthetic bone, and lesion conspicuity and decreased blurring compared with reduced-TR isotropic MAVRIC SL acquisitions ( < 0.032). Isotropic MAVRIC SL acquisitions improve SNR, conspicuity of lesions, and visualization of synovium and periprosthetic bone and decrease blurring compared with conventional MAVRIC SL acquisitions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2214/AJR.19.21606DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7020767PMC
December 2019

Long-term Evaluation of Meniscal Tissue Formation in 3-dimensional-Printed Scaffolds With Sequential Release of Connective Tissue Growth Factor and TGF-β3 in an Ovine Model.

Am J Sports Med 2019 09 6;47(11):2596-2607. Epub 2019 Aug 6.

Laboratory for Joint Tissue Repair and Regeneration, Orthopedic Soft Tissue Research Program, Hospital for Special Surgery, New York, New York, USA.

Background: Artificial meniscal scaffolds are being developed to prevent development of osteoarthritis after meniscectomy. Previously, it was reported that 3-dimensional (3D) anatomic scaffolds loaded with connective tissue growth factor (CTGF) and transforming growth factor β3 (TGF-β3) achieved meniscal regeneration in an ovine model. This was a relatively short-term study (3 months postoperative), and outcome analyses did not include magnetic resonance imaging (MRI).

Purpose: To evaluate long-term outcome of meniscal replacement with growth factor-laden poly-ε-caprolactone (PCL) scaffolds.

Study Design: Controlled laboratory study.

Methods: Anatomically shaped ovine meniscal scaffolds were fabricated from PCL with a 3D printer based on MRI data. Skeletally mature sheep (N = 34) were randomly allocated to 3 groups: scaffold without growth factor (0-µg group), scaffold with CTGF microspheres (µS) (5 µg) + TGF-β3 µS (5 µg) (5-µg group), and scaffold with CTGF µS (10 µg) + TGF-β3 µS (10 µg) (10-µg group). Unilateral medial meniscal replacement was performed. Animals were euthanized at 6 or 12 months. Regenerated meniscus, articular cartilage status, and synovial reaction were evaluated quantitatively with gross inspection, histology, and MRI. Kruskal-Wallis and Dunn tests were used to compare the 3 groups.

Results: Remnants of the PCL scaffold were evident in the 6-month specimens and were decreased but still present at 12 months in most animals. There were no significant differences among groups in gross inspection, histology, or MRI for either meniscal regeneration or articular cartilage protection. All experimental groups exhibited articular cartilage degeneration as compared with control (nonoperated). In terms of synovitis, there were no clear differences among groups, suggesting that growth factors did not increase inflammation and fibrosis. MRI revealed that meniscal extrusion was observed in most animals (82.7%).

Conclusion: Previously, the combination of CTGF and TGF-β3 was shown to stimulate mesenchymal stem cells into a fibrochondrocyte lineage. CTGF and TGF-β3 did not aggravate synovitis, suggesting no adverse response to the combination of 3D-printed PCL scaffold combined with CTGF and TGF-β3. Further work will be required to improve scaffold fixation to avoid meniscal extrusion.

Clinical Relevance: A significant advantage of this technique is the ability to print custom-fit scaffolds from MRI-generated templates. In addition, average-size menisci could be printed and available for off-the-shelf applications. Based on the 1-year duration of the study, the approach appears to be promising for meniscal regeneration in humans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/0363546519865513DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7422478PMC
September 2019

Reverse total shoulder arthroplasty: an imaging overview.

Skeletal Radiol 2020 Jan 18;49(1):19-30. Epub 2019 Jul 18.

Department of Diagnostic Radiology, Eulji University Medical Center, 68 Hangeulbiseok-ro, Nowon-gu, Seoul, 01830, South Korea.

Although not as common as hip or knee arthroplasty, shoulder arthroplasty is becoming a more common procedure. Reverse total shoulder arthroplasty (RTSA) is known to be an effective surgical procedure for massive irreparable rotator cuff tears, comminuted proximal humerus fractures, and revision shoulder arthroplasty. The utilization of RTSA has been increasing, and although complications following reverse arthroplasty have been reported, there are few reports in the literature that focus on the imaging features of RTSA. Herein, we demonstrate the biomechanics of RTSA, prosthesis components, indications, and imaging features of the normal postoperative appearance and various complications after RTSA. Familiarization with the normal and abnormal imaging appearances after RTSA can be helpful for appropriate management of patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00256-019-03275-0DOI Listing
January 2020
-->