Faculty Bibliography

Purpose: To correlate quantitative shear wave velocities (SWV) in the supraspinatus muscle (SSM) with that of the tendon (SST), and to evaluate whether SSM SWV changes precede morphologic fatty atrophy. Materials and Methods: An IRB-approved, HIPAA-compliant study of 45 patients (22 men, 23 women) with mean age of 59 (range 39-84) was conducted. Grayscale ultrasound and shear wave elastography images of the SST and SSM were performed with a 9MHz linear transducer on a Siemens S3000 scanner with VTIQ software (Siemens). Sample volume SWV values were obtained of the proximal (PSST) and distal tendon (DSST). Mean SSM SWV was reported from the software region of interest or calculated from sample volumes. Exclusion criteria included history of rotator cuff repair and non-target measurements on bone or peribursal fat. Qualitative tendon pathology grading was as follows: 1=normal or mild tendinosis without tear, 2=moderate or severe tendinosis without tear or mild tendinosis with low-grade partial tear, 3=partial tear with at least moderate tendinosis, and 4=full-thickness tear. All patients demonstrated normal grayscale appearance of the SSM, without evidence of fatty atrophy. Pearson and Spearman rank correlations were used for statistical analysis. Results: No statistically significant correlation was found between mean SSM SWV and mean PSST, DSST, or overall tendon SWV (R=0.14, p=0.396; R=0.04, p=0.832; R=0.06, p=0.731, respectively). There was no statistically significant correlation between SSM SWV and tendon grade (R=0.13, p=0.435). Mean PSST, DSST, and overall tendon SWV demonstrated weak negative correlation with qualitative tendon grade (R=-0.22, p=0.183; R=-0.32, p=0.054; R=-0.30, p=0.045, respectively). Conclusion: Supraspinatus muscle SWV does not appear to vary with quantitative tendon SWVor qualitative tendon grading. Aweak negative correlation between supraspinatus tendon SWV and qualitative tendon grade is compatible with tendon softening with progressive tendinopathy

PURPOSE: To compare diagnostic performance of a 5-min knee MRI protocol to that of a standard knee MRI. MATERIALS AND METHODS: One hundred 3 T (100 patients, mean 38.8 years) and 50 1.5 T (46 patients, mean 46.4 years) MRIs, consisting of 5 fast, 2D multi-planar fast-spin-echo (FSE) sequences and five standard multiplanar FSE sequences, from two academic centers (1/2015-1/2016), were retrospectively reviewed by four musculoskeletal radiologists. Agreement between fast and standard (interprotocol agreement) and between standard (intraprotocol agreement) readings for meniscal, ligamentous, chondral, and bone pathology was compared for interchangeability. Frequency of major findings, sensitivity, and specificity was also tested for each protocol. RESULTS: Interprotocol agreement using fast MRI was similar to intraprotocol agreement with standard MRI (83.0-99.5%), with no excess disagreement (/= 0.215), except more ACL tears on fast MRI (p = 0.021) and more cartilage defects on standard MRI (p < 0.001). Sensitivities (59-100%) and specificities (73-99%) of fast and standard MRI were not significantly different for meniscal and ligament tears (95% CI for difference, -0.08-0.08). For cartilage defects, fast MRI was slightly less sensitive (95% CI for difference, -0.125 to -0.01) but slightly more specific (95% CI for difference, 0.01-0.5) than standard MRI. CONCLUSION: A fast 5-min MRI protocol is interchangeable with and has similar accuracy to a standard knee MRI for evaluating internal derangement of the knee.

The aim of this study was to assess changes in shear wave velocity within the pronator quadratus muscle in patients following volar plate fixation for distal radial fractures compared to the contralateral nonoperated side. Shear wave velocity values were obtained in the short and long axis of the pronator quadratus muscle, which were analyzed separately. Patients were also stratified by age below or above 66 years. Statistical analysis was performed using paired sample Wilcoxon signed rank and t tests. Pearson and Spearman rank correlations were also used. Seventeen patients (nine women and eigth men; age range 33-82, mean 62.4 years) were prospectively assessed following open reduction volar plate fixation of distal radial fracture. A statistically significant reduction in the velocities of the treated versus the nontreated side was observed in the long axis of the muscle (3.29 versus 3.59 m/second; t test p = 0.035). The data provide evidence for shear wave elastography as a quantitative measure to assess postoperative changes in muscle and a potential tool to monitor the efficacy of rehabilitation.

We study packings of bidispersed spherical particles on a spherical surface. The presence of curvature necessitates defects even for monodispersed particles; bidispersity either leads to a more disordered packing for nearly equal radii, or a higher fill fraction when the smaller particles are accommodated in the interstices of the larger spheres. Variation in the packing fraction is explained by a percolation transition, as chains of defects or scars previously discovered in the monodispersed case grow and eventually disconnect the neighbor graph.

PURPOSE: To correlate shoulder ultrasound and radiography with F-FDG PET-CT to establish FDG uptake and therefore range of metabolic activity, as defined by SUV analysis, in various symptomatic shoulder pathologies. METHODS: Retrospective database query was performed for shoulder ultrasound and PET-CT scans between January 2012 and January 2017. Patients who had both studies within 1 year were included. Age- and sex-matched control patients with PET-CT scans only were also included. Retrospective image review determined shoulder pathology, and F-FDG SUVmax was measured using regions of interest placed at the glenohumeral joint, rotator cuff/bursa, and bicipital groove. Glenohumeral and acromioclavicular osteoarthrosis was assessed by radiography using the Kellgren-Lawrence classification system. RESULTS: Thirty-three patients had both imaging studies within 1 year. Ten patients (11 cases) were included, ranging in age from 56 to 90 years (mean, 67.9 years). Control subjects were selected among patients receiving PET-CT within 1 week of symptomatic patients. Glenohumeral osteoarthrosis was mild in 3 (27%), moderate in 2 (18%), and severe in 2 (18%). Six full-thickness rotator cuff tears (55%) were identified. SUVmax means were compared between the pathologic and control groups and were significantly higher in the former: glenohumeral joint (1.96 vs 1.32; P = 0.016), rotator cuff/bursa (2.80 vs 2.0; P = 0.005), and bicipital groove (2.19 vs 1.48; P = 0.007). The highest values were seen in full-thickness rotator cuff tear and severe biceps tenosynovitis. CONCLUSIONS: Increased metabolic activity about the shoulder is associated with a spectrum of rotator cuff, glenohumeral joint, and other soft tissue pathology that can be correlated with diagnostic ultrasound findings.

Objectives: Continuous gradient-echo (GRE) acquisition or "dynamic magnetic resonance imaging", allows for high-speed examination of pathologies based on joint motion. We sought to assess the efficacy of a radial GRE sequence with in the characterization of patellofemoral maltracking. Methods: Patients with suspected patellofemoral maltracking and asymptomatic volunteers were scanned using GRE (Siemens LiveView WIP; Malvern, PA, USA) at 3T in the axial plane at the patella level through a range of flexion-extension (0-30degree). The mean time to perform the dynamic component ranged from 3-7 mins. Lateral maltracking (amount patella moved laterally through knee ranging) was measured. Patella lateralization was categorized as normal (<= 2mm), mild (2-5mm), moderate (5-10mm), or severe (>10mm). Tibial tuberosity: trochlear groove (TT: TG) distance, trochlea depth, Insall-Salvati ratio, and patellofemoral cartilage quality (according to the modified Outerbridge grading system) were also assessed. Results: Eighteen symptomatic (6 men; 12 women, age range 14-51 years) and 10 asymptomatic subjects (6 men; 4 women, age range 25-68 years) were included. Two symptomatic patients underwent bilateral examinations. Lateralization in the symptomatic group was normal (n=10), mild (n=2), moderate (n=5) and severe (n=3). There was no abnormal maltracking in the volunteer group. Lateral tracking significantly correlated with TT: TG distance (F=38.0; p<.0001), trochlea depth (F=5.8; p=.023), Insall-Salvati ratio (F=4.642; p=.04) and Outerbridge Patella score (F=6.6; p=.016). Lateral tracking did not correlate with Outerbridge Trochlear score. Conclusion: Lateral tracking measured on GRE was found to significantly correlate with current measures of patellar instability including, TT: TG, trochlea depth, and the Insall-Salvati ratio. GRE is a rapid and easily performed addition to the standard protocol for kinematic patellofemoral motion and can add dynamic information on patellofemoral tracking. This may be help determine if an isolated MPFL or an MPFL reconstruction and tibial tubercle osteotomy is needed to treat patella instability

OBJECTIVE: To describe a 4-year clinical experience with ultrasound-guided therapeutic perineural injections of peripheral nerves about the foot and ankle. MATERIALS AND METHODS: Retrospective analysis of foot and ankle perineural injections performed between January 2012 and August 2016. Demographics, clinical indications, presence of structural pathology, immediate and interval pain relief, as well as complications were recorded. RESULTS: Fifty-nine therapeutic injections were performed among 46 patients, accounting for multiple injections in a single visit or multiple visits [mean age = 43 years (range 18-75), 31 female (67%) and 15 male (33%)]. Most commonly, perineural injections involved the hallux branch of the medial plantar nerve (n = 17, 22%). Least commonly, perineural injections involved the saphenous nerve (n = 3, 4%). Other injections in our series include sural (10), superficial (11) and deep (7) peroneal, medial (5) and lateral (3) plantar nerves, and the posterior tibial nerve (3). Ultrasound evaluation revealed structural abnormality associated with the nerve in 30 cases (51%)-most commonly thickening with perineural scarring (n = 14). Of 45 injections with complete documentation, immediate relief of symptoms was reported in 43 (96%) cases. Interval symptom relief was achieved in 23 injections [short term (n = 12), intermediate (n = 6), and long term (n = 5)] out of 38 for which follow-up was available (61%). Complications are rare, occurring in only one case. CONCLUSION: Ultrasound-guided perineural injections about the foot and ankle are safe and provide lasting symptomatic relief for many indications. Concomitant sonographic evaluation identifies structural abnormalities that may contribute to neuropathic symptoms, allowing targeting of injection or clinical therapy.

Sonographic-guided tibial nerve block allows for rapid anesthetization of the heel and plantar regions of the foot. We describe a variant technique for tibial nerve regional anesthesia utilizing perineural injection of the medial plantar nerve proximal to the sustentaculum tali where the nerve is superficial and readily accessed, with resultant retrograde flow of local anesthetic proximally. Perineural injection of the medial plantar nerve at the inframalleolar level provides a simple, safe, and effective alternative method to achieve tibial nerve block for regional anesthesia in a variety of procedures. (c) 2017 Wiley Periodicals, Inc. J Clin Ultrasound, 2017.

Purpose: To evaluate the clinical impact of the introduction of MR neurographic imaging of the lumbosacral plexus at a large academic institution. Materials and Methods: A retrospective analysis of all MR lumbosacral neurograms performed at our institution between 2011 and 2016 was performed. For each neurogram, age, sex, reason for exam, imaging findings, and treatment was recorded. In addition, for cases in which treatment was noted, the follow up patient outcome (if present) was also noted. Results: A total of 142 lumbosacral plexus neurograms were performed (53 male, 89 female); the mean age was 47.2 years (range 19-79). 105 studies demonstrated positive findings. 35 scans demonstrated positive neural findings. 70 demonstrated positive non neural findings. 37 studies were negative for both neural and non-neural abnormalities. Regarding outcomes; 4 underwent surgery, 21 image-guided radiological treatments, 3 patients underwent non image-guided (trigger point) injections and the remainder were managed medically. Image-guided procedures included fluoroscopy guided facet joint injections (2), fluoroscopy guided sacroiliac joint injections (1), lumbosacral epidural steroid injection (6), hip joint injections (3), ultrasound-guided perineural injection of the sciatic nerve/ piriformis (7), pudendal nerve (1), and genitofermoral nerve (1). Conclusion: MR neurography of the lumbosacral plexus allows detailed evaluation of the neural structures but frequently demonstrates non neural pathology. While the majority of cases received medical or conservative treatment, a significant number went on to image-guided treatment. A familiarity with the neurogram imaging findings and possible treatment options may be of use to the MSK interventionalist

Purpose: To retrospectively correlate the MR imaging, arthroscopic and histopathologic appearance of resected long of biceps tendon samples following biceps tenodesis. Materials and Methods: Following IRB approval, a retrospective review of 63 cases between 2013 and 2016 was performed in patients who had undergone preoperative shoulder MRI, arthroscopy and long head of the biceps tenotomy and tenodesis followed by histopathologic inspection of the excised sample. Independently, two blinded radiologists reviewed the MRI appearance of the biceps tendon. Biceps tendon split tearing, subluxation and dislocation were described separately. A blinded shoulder orthopedist and a pathologist with bone and soft tissue specialization reviewed all operative imaging and pathologic slides respectively. Statistical analysis including inter-rater agreement was performed to assess concordance in the degree of agreement among pathologist, surgeon and radiologist. Results: Of the 63 samples of biceps tissue analyzed 59 demonstrated a histopathological abnormality pertaining to the tendon or tenosynovium. Four samples were reported as histopathologically normal.13/59 (22%) of samples with histopathological abnormality demonstrated normal appearance on MR imaging. Of these, the most common reported pathology finding was mild fibrosis and/or myxoid degeneration. Histopatholgical abnormalities of the tendon positively correlating with MRI and arthoscopic findings included intra-tendinous granulation tissue, severe myxoid degeneration and fibrocartilage tendinous tissue. Conclusion: A significant number of patients with histopathological evidence of tendinosis including mild fibrosis and myxoid degeneration demonstrate no abnormality on MRI