Faculty Bibliography

BACKGROUND: Altered biomechanics from repetitive microtrauma, such as long practice hours in en pointe (tip of the toes) or demi pointe (balls of the feet) predispose ballet dancers to a multitude of musculoskeletal pathologies particularly in the lower extremities. Both ultrasound and magnetic resonance imaging (MRI) are radiation-sparing modalities which can be used to confidently evaluate these injuries, with ultrasound (US) offering the added utility of therapeutic intervention at the same time in experienced hands. QUESTIONS/PURPOSES: The purposes of this paper were: (1) to illustrate the US and MRI features of lower extremity injury patterns in ballet dancers, focusing on pathologies commonly encountered at a single orthopedic hospital; (2) to present complementary roles of both ultrasound and MRI in the evaluation of these injuries whenever possible; (3) to review and present our institutional approach towards therapeutic ultrasound-guided interventions by presenting explicit cases. METHODS: Online searches were performed using the search criteria of "ballet biomechanics" and "ballet injuries." The results were then further narrowed down by limiting articles published in the past 15 years, modality (US and MRI), anatomical region (foot and ankle, hip and knee) and to major radiology, orthopedics, and sports medicine journals. RESULTS: Performing ballet poses major stress to lower extremities and predisposes dancer to several musculoskeletal injuries. These can be adequately evaluated by both US and MRI. US is useful for evaluating superficial structures such as soft tissues, tendons, and ligaments, particularly in the foot and ankle. MRI provides superior resolution of deeper structures such as joints, bone marrow, and cartilage. In addition, US can be used as a therapeutic tool for providing quick symptomatic improvement in these athletes for who "time is money". CONCLUSION: Performing ballet may cause major stress to the lower extremities, predominantly affecting the foot and ankle, followed by the knee and hip. US and MRI play complementary roles in evaluating various orthopedic conditions in ballet dancers, with US allowing for dynamic evaluation and guidance for interventions.

This retrospective study evaluated the technical success rate of a novel injection into the long head of the biceps tendon sheath by a rotator interval approach in 26 patients. A 25-gauge, 1.5-in needle was positioned into the rotator interval from a lateral approach, where a therapeutic injection was performed. Postinjection sonograms images were reviewed to assess for fluid within the sheath to calculate the technical success rate. Fluid distention of the biceps tendon sheath was shown in all 26 cases, corresponding to a 100% technical success rate. In addition, postinjection ultrasound imaging of the anterior shoulder provided additional diagnostic findings in 6 of 26 patients (23%).

Purpose To determine whether quantitative differences in shear-wave velocity (SWV) exist between normal skeletal muscle and those affected by GNE-related myopathy and to examine the effects of muscle anisotropy, depth, and axial preload on SWV in a healthy control group. Materials and Methods This study was approved by the institutional review board and compliant with HIPAA. Informed consent was obtained from all study volunteers. Eight patients (four women and four men aged 30-50 years) with genetically and biopsy-proved GNE-related myopathy and five healthy volunteers (three women and two men aged 27-33 years) underwent SWV imaging with use of a 9-MHz linear transducer. The gastrocnemius muscles were evaluated in the patients with GNE-related myopathy, and the gastrocnemius, vastus lateralis, and rectus femoris muscles were evaluated in the healthy cohort. The effect of muscle anisotropy, axial preload, and sample volume depth were examined in the healthy cohort. The effect of anisotropy at a fixed depth and preload were examined in the patients with GNE-related myopathy. Results Irrespective of the muscle, the mean SWV was significantly higher with the transverse orientation than with the longitudinal orientation (P < .001). In the healthy cohort, the mean SWV for superficial measurements was significantly lower than that for deep measurements (P < .02). The mean SWV with preload was significantly higher with compression (P < .001) for the rectus femoris only. The mean SWV was significantly lower in patients with GNE-related myopathy than in control subjects (P < .02). Conclusion SWV parametric imaging may provide a useful quantitative adjunct in the assessment of disease activity in patients with GNE-related myopathy. There is diminished SWV and muscle anisotropy in GNE-related myopathy. ((c)) RSNA, 2015.

OBJECTIVE: The purpose of this article is to review the normal anatomy and pathologic conditions of the shoulder on the basis of the appearance on MR and ultrasound images obtained during performance of abduction external rotation and flexion adduction internal rotation positional maneuvers. CONCLUSION: Positional MRI and ultrasound are highly useful in evaluation of the shoulder. Knowledge of the normal appearance of anatomic structures and pathologic changes in nontraditional imaging planes is necessary to avoid pitfalls in interpretation.

OBJECTIVES: To compare the effects of ultrasound-guided platelet-rich plasma (PRP) and whole blood (WB) injections in patients with chronic hamstring tendinopathy. METHODS: In a prospective double-blind randomized controlled trial, PRP or WB was injected under ultrasound guidance into the proximal hamstring tendon in a cohort of patients with clinically suspected hamstring tendinosis. Questionnaires were administered before injection and 2, 6, and 12 weeks and 6 months after injection. Pain and function outcomes were measured via the Modified Harris Hip Score (MHHS), Hip Outcome Scores for activities of daily living (ADL) and sport-specific function, and International Hip Outcome Tool 33 (IHOT-33). Diagnostic ultrasound was used to compare preinjection and 6-month postinjection tendon appearances. RESULTS: The WB group showed greater improvements in pain and function over the PRP group before 12 weeks, whereas the PRP group showed improved outcomes over WB at 6 months. None of these between-group outcome measures, except 6-week IHOT-33, showed statistical significance. Comparing preinjection and 6-month scores, the PRP group showed significant improvements in ADL (P = .018) and IHOT-33 (P = .28) scores, whereas the WB group showed no significant improvements from baseline. The WB group showed significantly decreased pain with 15-minute sitting (P= .008) at 6 months. Ultrasound imaging showed no significant differences between PRP and WB group tendon appearances. CONCLUSIONS: Both PRP and WB groups showed improvements in all outcome measures at 6 months. The PRP group showed significant improvements in 6-month ADL and IHOT-33 scores. The WB group reached significance in 15-minute sitting pain. No significant between-group differences were observed at any time point.

Substantial cost, morbidity, and mortality are associated with acute proximal femoral fracture and may be reduced through an optimized diagnostic imaging workup. Radiography represents the primary diagnostic test of choice for the evaluation of acute hip pain. In middle aged and elderly patients with negative radiographs, the evidence indicates MRI to be the next diagnostic imaging study to exclude a proximal femoral fracture. CT, because of its relative decreased sensitivity, is only indicated in patients with MRI contraindications. Bone densitometry (DXA) should be obtained in patients with fragility fractures. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

This article provides a brief overview of the current state of ultrasound (US) imaging of rotator cuff repairs with emphasis on current morphological assessment and development of newer techniques in which US may play an important role in assessing healing response. Emphasis is on the supraspinatus tendon inasmuch as it is the most commonly affected tendon in rotator cuff disease. Assessment of the tendon repair following joint replacement is also commented on in which the standard anterior approach may be associated with dehiscence of the subscapularis tendon.

OBJECTIVE: To investigate the efficacy of using contrast-enhanced ultrasound to assess the relationship of altered vascularity and tendon morphology following injection of platelet-rich plasma (PRP) for lateral epicondylitis. MATERIALS AND METHODS: This study prospectively evaluated six patients who had a baseline ultrasound confirming tendinosis of the common extensor tendon. Patients received a single 3-ml PRP injection under ultrasound guidance. Grayscale images of the injected elbow were obtained at baseline and were repeated at 1 and 6 months after injection. DEFINITY(R) contrast was also injected after by 2 sets of wrist-extension exercises in order to obtain contrast-enhanced images of the elbow. Qualitative and quantitative analyses of the level of enhancement to the regions of interest were performed using off-line quantitative analysis software. RESULTS: All patients had either moderate or severe common extensor tendinosis as determined on clinical examination and baseline imaging. Five patients demonstrated improved tendon morphology using ultrasound imaging 6 months after PRP injection (one patient was lost to follow-up). At baseline, there was evidence of increased vascularity at the myotendinous junction (MT) of the common extensor tendon when compared to its footprint (FP). There was a trend towards no change in FP vascularity between baseline and 6 months (p = 0.062) and between 1 and 6 months (p = 0.288). There was a trend for increased vascularity to the MT region from baseline to 6 months (p = 0.433) and from 1 to 6 months (p = 0.783). CONCLUSIONS: Contrast-enhanced ultrasound provides a sensitive method the display alterations in vascularity in the common extensor tendon of the elbow. PRP therapy for lateral epicondylitis can improve extensor tendon morphology. Corresponding increased extensor tendon FP vascularity, however, was not seen. There is a trend for increased vascularity at the MT up to 6 months following PRP injection, based on limited pilot data.

Chronic peripheral nerve pain is a common problem that can arise from numerous causes, for which neurolysis is a therapeutic option. It is postulated that cryotherapy will have less adverse events than other methods of nerve ablation. A retrospective case series review was performed in patients who had undergone sonographically guided cryoneurolysis for Morton neuromas, postsurgical and posttraumatic neuromas, and idiopathic neuralgia. Fifteen of 20 patients had a positive response to cryoneurolysis, as did 2 of 4 patients with borderline symptoms for chronic regional pain syndrome. In view of our positive results, we believe that cryoneurolysis should be considered a reasonable option in performing neurolytic therapy.

OBJECTIVE: Characterization of the distribution and imaging characteristics of platelet-rich plasma (PRP) and autologous blood after injection is currently limited despite the growing use. We sought to improve understanding of the distribution of PRP or autologous blood after it has been injected into a tendon to evaluate whether injected materials truly stayed within the local region of injection. MATERIALS AND METHODS: Fifty ultrasound-guided PRP or autologous blood injections performed for tendinopathy were retrospectively reviewed. Consensus review of the imaging data was performed by two radiologists to characterize the distribution of the injectate (i.e., within the tendon, along the tendon sheath, along the paratenon, or leakage into the adjacent joint or surrounding soft tissues). The presence of fluid and microbubbles from the injectate served as an indicator of material distribution. RESULTS: Image review verified the injectate within the tendon in 100% of cases. In 98% of reviewed cases, injected PRP or autologous blood dissected beyond the local injection site (defined as > 2 cm from the site of injection) and was identified in adjacent soft tissues in 51% of cases. Visualization of injectate along a paratenon or tendon sheath (when applicable) was seen in 86% and 100% of cases respectively; however, intraarticular extension was uncommon (8%). CONCLUSION: Our study showed that postinjection imaging may be of value in assessing the anatomic distribution of injectate after intratendinous therapy. Furthermore, our initial review found that in the majority of cases injected blood products tended to distribute beyond the local area of injection.