Smith, Jay

Background: Lateral elbow tendinosis (epicondylitis) is a common condition both in primary care and specialty clinics. Purpose: To evaluate the natural history (ie, incidence, recurrence, and progression to surgery) of lateral elbow tendinosis in a large population. Study Design: Descriptive epidemiology study. Methods: The study population comprised a population-based incidence cohort of patients with new-onset lateral elbow tendinosis between January 1, 2000, and December 31, 2012. The medical records of a 10% random sample (n = 576) were reviewed to ascertain information on patient and disease characteristics, treatment modalities, recurrence, and progression to surgery. Age- and sex-specific incidence rates were calculated and adjusted to the 2010 US population. Results: The age- and sex-adjusted annual incidence of lateral elbow tendinosis decreased significantly over time from 4.5 per 1000 people in 2000 to 2.4 per 1000 in 2012 ( P < .001). The recurrence rate within 2 years was 8.5% and remained constant over time. The proportion of surgically treated cases within 2 years of diagnosis tripled over time, from 1.1% during the 2000-2002 time period to 3.2% after 2009 ( P < .00001). About 1 in 10 patients with persistent symptoms at 6 months required surgery. Conclusion: The decrease in incidence of lateral elbow tendinosis may represent changes in diagnosis patterns or a true decrease in disease incidence. Natural history data can be used to help guide patients and providers in determining the most appropriate course at a given time in the disease process. The study data suggest that patients without resolution after 6 months of onset may have a prolonged disease course and may need surgical intervention.

Background The use of diagnostic and interventional ultrasound has significantly increased over the past decade. A majority of the increased utilisation is by non-radiologists. In sports medicine, ultrasound is often used to guide interventions such as aspirations, diagnostic or therapeutic injections, tenotomies, releases and hydrodissections. Objective Critically review the literature related to the accuracy, efficacy and cost-effectiveness of ultrasound-guided injections (USGIs) in major, intermediate and small joints; and soft tissues. Design Systematic review of the literature. Results USGIs are more accurate than landmark-guided injections (LMGIs; strength of recommendation taxonomy (SORT) Evidence Rating=A). USGIs are more efficacious than LMGIs (SORT Evidence Rating=B). USGIs are more cost-effective than LMGIs (SORT Evidence Rating=B). Ultrasound guidance is required to perform many new procedures (SORT Evidence Rating=C). Conclusions The findings of this position statement indicate there is strong evidence that USGIs are more accurate than LMGI, moderate evidence that they are more efficacious and preliminary evidence that they are more cost-effective. Furthermore, ultrasound-guided (USG) is required to perform many new, advanced procedures and will likely enable the development of innovative USG surgical techniques in the future.

AbstractImproving the effectiveness of adipose‐tissue derived human mesenchymal stromal/stem cells (AMSCs) for skeletal therapies requires a detailed characterization of mechanisms supporting cell proliferation and multi‐potency. We investigated the molecular phenotype of AMSCs that were either actively proliferating in platelet lysate or in a basal non‐proliferative state. Flow cytometry combined with high‐throughput RNA sequencing (RNASeq) and RT‐qPCR analyses validate that AMSCs express classic mesenchymal cell surface markers (e.g., CD44, CD73/NT5E, CD90/THY1, and CD105/ENG). Expression of CD90 is selectively elevated at confluence. Self‐renewing AMSCs express a standard cell cycle program that successively mediates DNA replication, chromatin packaging, cyto‐architectural enlargement, and mitotic division. Confluent AMSCs preferentially express genes involved in extracellular matrix (ECM) formation and cellular communication. For example, cell cycle‐related biomarkers (e.g., cyclins E2 and B2, transcription factor E2F1) and histone‐related genes (e.g., H4, HINFP, NPAT) are elevated in proliferating AMSCs, while ECM genes are strongly upregulated (>10‐fold) in quiescent AMSCs. AMSCs also express pluripotency genes (e.g., POU5F1, NANOG, KLF4) and early mesenchymal markers (e.g., NES, ACTA2) consistent with their multipotent phenotype. Strikingly, AMSCs modulate expression of WNT signaling components and switch production of WNT ligands (from WNT5A/WNT5B/WNT7B to WNT2/WNT2B), while upregulating WNT‐related genes (WISP2, SFRP2, and SFRP4). Furthermore, post‐proliferative AMSCs spontaneously express fibroblastic, osteogenic, chondrogenic, and adipogenic biomarkers when maintained in confluent cultures. Our findings validate the biological properties of self‐renewing and multi‐potent AMSCs by providing high‐resolution quality control data that support their clinical versatility. J. Cell. Biochem. 115: 1816–1828, 2014. © 2014 Wiley Periodicals, Inc.

ABSTRACTIntroduction: The primary aim of this investigation was to determine whether use of write‐zoom magnification affects sonographically determined cross‐sectional area (CSA) of peripheral nerves. Methods: CSAs of the median (MN) and posterior interosseous (PIN) nerves were measured in 22 limbs from 11 asymptomatic volunteers using both standard imaging and write‐zoom magnification. CSA measurements were repeated on the same images 1 week later. Results: The average CSA of write‐zoomed images for the MN was significantly larger at both measurement sessions (week 1: 11.1 mm2 write‐zoom vs. 10.0 mm2 standard, P = 0.019; week 2: 11.8 mm2 vs. 10.4 mm2, P = 0.023). Similar differences were noted for the PIN (week 1: 2.3 mm2 vs. 1.9 mm2, P = 0.002; week 2: 2.5 mm2 vs. 1.9 mm2, P = 0.001). Conclusions: Write‐zoom magnification may significantly increase the measured CSA of peripheral nerves. These changes appear to be more substantial when smaller nerves are measured. Muscle Nerve 51: 30–34, 2015

A 63‐year‐old right‐handed office worker presented with acute right wrist pain after lifting a heavy file at work. Results of a clinical examination suggested flexor carpi radialis tendinopathy. Diagnostic ultrasound (US) not only detected a complete flexor carpi radialis tear but also revealed the presence of a concomitant flexor carpi radialis brevis (FCRB) tendon with associated tenosynovitis. The ability of US to correctly identify the FCRB has not been previously reported. Furthermore, the US appearance of FCRB tendinopathy and tenosynovitis has not been described. High‐resolution US can identify the FCRB muscle‐tendon in the wrist region. Sonologists and sonographers should be aware of the US appearance of the FCRB as well as the potential for the FCRB to contribute to radial wrist pain syndromes.

A 16‐year‐old high school football player presented with 4 months of anterior knee pain and small, mobile, prepatellar “lumps” after falling onto an opponent's cleat. He reported knee pain primarily during knee flexion and direct pressure during squatting and kneeling. Knee radiographs were unremarkable. Ultrasonography revealed multiple, freely mobile, subcutaneous nodules of variable size and echogenicity in the prepatellar region. Analysis of magnetic resonance imaging suggested possible fat necrosis but was nondiagnostic. The patient opted for surgical exploration, at which time multiple, opalescent subcutaneous nodules were removed. Pathology was consistent with encapsulated fat necrosis. After surgery, his symptoms resolved, and he returned to sports without restrictions.

ObjectivesTo 1) describe and validate an ultrasound‐guided ischial bursa injection technique in an unembalmed cadaveric model and 2) to compare the distance between the ischial tuberosity and the sciatic nerve in a hip neutral versus 90° flexed hip position in asymptomatic volunteers.DesignThe first part was a single‐blind prospective study. The second part was a prospective cohort study.SettingAn academic institution procedural skills laboratory and outpatient clinic.ParticipantsThe first part of the study involved 1 cadaveric specimen. The second part of the study involved 20 asymptomatic subjects. The mean age of the subjects was 28 years, and the mean (standard deviation) body mass index was 23.2 ± 2.8 kg/m2 (minimum, 18.3 kg/m2; maximum, 29.5 kg/m2).MethodsIn the first part of the study, a single operator completed bilateral ultrasound‐guided ischial bursa injections in an unembalmed cadaveric specimen by using diluted colored latex. In the second part of the study, ultrasound was used in 20 asymptomatic volunteer subjects (10 men and 10 women) to measure the distance from the lateral edge of the ischial tuberosity to the sciatic nerve.Main Outcome MeasurementsThe injections were graded for accuracy as follows: accurate (all injectate contained within the ischial bursa), accurate with overflow (injectate within the ischial bursa but also located in adjacent structures other than the needle track), or inaccurate (injectate not within the ischial bursa). The second part of the study measured the distance from the ischial tuberosity to the sciatic nerve with subjects in 2 different positions (prone and side lying with the tested hip flexed to 90°).ResultsPostinjection cadaveric dissections revealed that both ultrasound‐guided injections accurately placed liquid latex within the ischial bursae. There was no evidence of injury to surrounding neurovascular structures. Among asymptomatic volunteers, the average distance between the ischial tuberosity and the sciatic nerve increased from 28.4 mm (range, 20.5‐38.9 mm) in the neutral position to 41.9 mm (range, 30.9‐66.0 mm) with the hip flexed to 90° (average change, 13.5 mm away from the ischial tuberosity; P = .0001).ConclusionsUltrasound‐guided ischial bursa injections are technically feasible. Flexing the hip to 90° increases the distance between the ischial tuberosity and the sciatic nerve in asymptomatic volunteers, thus potentially resulting in a safer needle trajectory when ischial bursa injections are clinically indicated. Further investigation in clinical settings is warranted to validate these findings.

Background: Invasive leg compartment testing may be performed to diagnose chronic exertional compartment syndrome. No prior study has assessed the accuracy of leg compartment needle tip access. Purpose: This study was undertaken to describe and determine the accuracy of palpation-guided and ultrasound-guided techniques for needle tip placement into the deep and superficial posterior leg compartments by a less experienced clinician and a more experienced clinician using a cadaveric model. Study Design: Controlled laboratory study. Methods: Twenty unembalmed adult lower limb cadaveric specimens were used for the study. Two investigators, a sports medicine fellow with 10 months of musculoskeletal ultrasound experience and a staff physiatrist with 3 years of musculoskeletal ultrasound experience, each performed 1 palpation-guided and 1 ultrasound-guided colored latex dye injection into the deep and superficial posterior leg compartments of each cadaveric specimen. A blinded investigator dissected the specimens and graded them for accuracy. Results: The accuracy rates of palpation-guided (accuracy rate, 90%; 95% confidence interval [CI], 76%-97%) and ultrasound-guided (accuracy rate, 88%; 95% CI, 73%-95%) deep posterior compartment injections were statistically equivalent ( P = 1.000). All 80 injections performed into the superficial posterior compartment were accurate (accuracy rate, 100%; 95% CI, 89%-100%). The accuracy of the less experienced investigator (total injection accuracy rate, 88%; 95% CI, 73%-95%) and the more experienced investigator (total injection accuracy rate, 90%; 95% CI, 76%-97%) were not significantly different ( P = 1.000). Conclusion: Needle tip placement into the deep and superficial posterior leg compartments is relatively accurate with palpation guidance regardless of level of experience, and does not improve with the use of ultrasound guidance. Clinical Relevance: Ultrasound guidance does not appear to be indicated for routine deep or superficial posterior leg compartment pressure testing. However, this does not preclude the need for ultrasound guidance in selected clinical scenarios.