Marnix van Holsbeeck

DIAGNOSIS OF CARPAL TUNNEL SYNDROME: Ultrasound Versus Electromyography

This article presents a new technique for diagnosing carpal tunnel syndrome using ultrasound. The ultrasound characteristics of the normal and abnormal median nerve are discussed in relation to carpal tunnel syndrome. The development of ultrasound as a new diagnostic modality for carpal tunnel syndrome is presented in a three-part study correlating the ultrasound measurements of the median nerve and electromyogram of the median nerve. A new algorithm for evaluating patients with carpal tunnel syndrome is presented.

Evidence of Subclinical Medial Collateral Ligament Injury and Posteromedial Impingement in Professional Baseball Players

Background Recognition and treatment of elbow conditions such as medial collateral ligament injury and posteromedial impingement are increasing in throwing athletes. Magnetic resonance imaging may provide pivotal information in the management of these athletes. Knowledge of the utility of magnetic resonance imaging has become widespread throughout the baseball community. However, data on the frequency and extent of asymptomatic magnetic resonance imaging findings in the elbows of this throwing population are lacking. Hypothesis Abnormalities in the throwing elbows of asymptomatic professional baseball players compared to the nonthrowing elbows are frequently seen in magnetic resonance images. Study Design Descriptive anatomical study. Methods Sixteen asymptomatic professional baseball players with no history of injury underwent bilateral elbow magnetic resonance imaging using a standardized sequencing protocol. The magnetic resonance images were reviewed, in a blinded fashion, by 2 musculoskeletal radiologists and 1 orthopaedic surgeon. Results Medial collateral ligament abnormalities (including thickening, signal heterogeneity, or discontinuity) were present in 87% of players’ dominant elbows. Findings consistent with posteromedial impingement were present in 13 of 16 subjects. There was a significant correlation between medial collateral ligament thickening and posteromedial subchondral sclerosis (P = .04). The throwing elbow was correctly identified in all 16 subjects. No significant correlation between magnetic resonance imaging findings and age could be detected. Conclusions This study demonstrates a high rate of abnormal magnetic resonance imaging findings in asymptomatic throwers’ elbows. These baseline findings must be considered when magnetic resonance imaging is being used as a factor in treatment decisions.

Ultrasound for the early diagnosis of fracture healing after interlocking nailing of the tibia without reaming.

Fourteen fractures (8 open, 6 closed) were treated with small-diameter interlocking tibial nails and observed for at least 1 year. Radiographs were obtained to monitor the maintenance of reduction and fracture healing. The treating orthopaedic surgeon was blinded to the results of ultrasound studies, which were obtained at 2-week intervals for 10 weeks postoperatively and read by a radiologist who was blinded to the clinical and radio-graphic progress. Ultrasound correctly predicted fracture healing in all 9 fractures that subsequently progressed to fracture union. Of the 5 fractures that did not heal and required secondary procedures, ultrasound predicted delayed healing in 4 fractures. Overall, ultrasound was able to predict fracture healing before it was radiographically evident. Ultrasound may provide important prognostic information concerning tibial fracture healing after treatment using interlocking nails without reaming. Additional study is warranted.

Sonography of tendons

Musculoskeletal ultrasonography (MSUS) has been refined by improved examination techniques and higher frequency transducer technology. Sonography is the modality of choice in the screening of tendon disorders. The accuracy in diagnosing tendon lesions has improved with better understanding of the sonographic anatomy and the pathophysiology of tendons. The sonographic appearance of tears, tendon dislocations, tendinitis, tenosynovitis, insertion tendinopathy, ganglion cysts, and bursitis is described. Normal variants that mimic tendon disease are shown. The tendons of the shoulder, elbow, wrist, hand, knee, ankle, and foot are considered.

In Vivo Shoulder Function After Surgical Repair of a Torn Rotator Cuff Glenohumeral Joint Mechanics, Shoulder Strength, Clinical Outcomes, and Their Interaction

Background: Surgical repair of a torn rotator cuff is based on the belief that repairing the tear is necessary to restore normal glenohumeral joint (GHJ) mechanics and achieve a satisfactory clinical outcome. Hypothesis: Dynamic joint function is not completely restored by rotator cuff repair, thus compromising shoulder function and potentially leading to long-term disability. Study Design: Controlled laboratory study and Case series; Level of evidence, 4. Methods: Twenty-one rotator cuff patients and 35 control participants enrolled in the study. Biplane radiographic images were acquired bilaterally from each patient during coronal-plane abduction. Rotator cuff patients were tested at 3, 12, and 24 months after repair of a supraspinatus tendon tear. Control participants were tested once. Glenohumeral joint kinematics and joint contact patterns were accurately determined from the biplane radiographic images. Isometric shoulder strength and patient-reported outcomes were measured at each time point. Ultrasound imaging assessed rotator cuff integrity at 24 months after surgery. Results: Twenty of 21 rotator cuff repairs appeared intact at 24 months after surgery. The humerus of the patients’ repaired shoulder was positioned more superiorly on the glenoid than both the patients’ contralateral shoulder and the dominant shoulder of control participants. Patient-reported outcomes improved significantly over time. Shoulder strength also increased over time, although strength deficits persisted at 24 months for most patients. Changes over time in GHJ mechanics were not detected for either the rotator cuff patients’ repaired or contralateral shoulders. Clinical outcome was associated with shoulder strength but not GHJ mechanics. Conclusion: Surgical repair of an isolated supraspinatus tear may be sufficient to keep the torn rotator cuff intact and achieve satisfactory patient-reported outcomes, but GHJ mechanics and shoulder strength are not fully restored with current repair techniques. Clinical Relevance: The study suggests that current surgical repair techniques may be effective for reducing pain but have not yet been optimized for restoring long-term shoulder function.

Entrapment of the Posterior Interosseous Nerve at the Arcade of Frohse With Sonographic, Magnetic Resonance Imaging, and Intraoperative Confirmation

Entrapment of the radial nerve, specifically the deep branch of the radial nerve (DBRN) in the arcade of Frohse, was first described in 1963. 1 Prolonged entrapment may lead to a constellation of symptoms described in posterior interosseous nerve (PIN) paralysis. 2 Reported attempts at diagnosis using imaging have mostly involved magnetic resonance imaging (MRI), with a limited number of studies characterizing the utility of sonography. Confirmation of entrapment via MRI, sonography, and gross specimens obtained intraoperatively during surgical decompression is presented.

Pre- and Postseason Dynamic Ultrasound Evaluation of the Pitching Elbow

PURPOSE To use ultrasound imaging to document changes over time (i.e., preseason v postseason) in the pitching elbow of high school baseball pitchers. METHODS Twenty-two high school pitchers were prospectively followed. Pitchers were evaluated after a 2-month period of relative arm rest via preseason physical exams, dynamic ultrasound imaging of their throwing elbow, and the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) assessment. Players were reevaluated within 1 week of their last game. Dynamic ultrasound images were then randomized, blinded to testing time point, and evaluated by 2 fellowship-trained musculoskeletal radiologists. RESULTS Average pitcher age was 16.9 years. Average pitches thrown was 456.5, maximum velocity 77.7 mph, games pitched 7.3, and days off between starts 6.6. From preseason to postseason, there were significant increases in ulnar collateral ligament (UCL) thickness (P = .02), ulnar nerve cross-sectional area (P = .001), UCL substance heterogeneity (P = .001), and QuickDASH scores (P = .03). In addition, there was a nonsignificant increase in loaded ulnohumeral joint space (P = .10). No pitchers had loose bodies on preseason exam, while 3 demonstrated loose bodies postseason. The increase in UCL thickness was significantly associated with the number of bullpen sessions per week (P = .01). The increase in ulnar nerve cross-sectional area was significantly associated with the number of pitches (P = .04), innings pitched (P = .01), and games pitched (P = .04). CONCLUSIONS The stresses placed on the elbow during only one season of pitching create adaptive changes to multiple structures about the elbow including UCL heterogeneity and thickening, increased ulnohumeral joint space laxity, and enlarged ulnar nerve cross-sectional area. LEVEL OF EVIDENCE Level II prospective observational study.

Educational benefits of fusing magnetic resonance imaging with sonograms

To investigate whether providing sonographic (US)/MRI fusion images will enhance the ability of medical students and radiology residents to identify MSK anatomy on sonograms alone.

Sonographic Depiction of Trigger Fingers in Acromegaly

Objective. The purpose of this study was to compare the prevalence of trigger fingers in patients with acromegaly versus an unaffected control group. Methods. This study was performed with Institutional Review Board approval, and informed written consent was obtained from each patient and control participant. The diagnosis was made by a combination of clinical symptoms and sonographically measured thickening of the first annular (A1) pulley. The A1 pulley thickness was measured in 40 patients and 40 control participants by means of a 17–5 MHz high‐resolution transducer. Thickening of the A1 pulley and abnormalities of the underlying flexor tendons associated with the clinical sign were diagnostic for a trigger finger. The acromegalic patients were divided into groups according to disease activity and therapy. The study was performed at the baseline and at a follow‐up after 1 year. Results. At the baseline, clinical and sonographic findings were consistent with trigger fingers in 25% of patients (6 at presentation and 4 with uncontrolled disease). After 1 year, the trigger fingers recovered in the patients who were not receiving any treatment at the beginning of the study. In patients with uncontrolled disease, the condition remained unchanged. The A1 pulley thickness was greater in the acromegalic patients than control participants (mean ± SD, 0.44 ± 0.19 versus 0.24 ± 0.05 mm; P < .05). In the patients treated for acromegaly, the trigger fingers disappeared, and a reduction in the A1 pulley thickness was noted (P < .05) at the follow‐up. Conclusions. Trigger fingers were observed in 25% of the acromegalic patients but in none of the control participants. The A1 pulley was significantly thicker in the acromegalic patients and normalized after 1 year in some who were treated for the disease.

Gonococcal Arthritis of the Shoulder and Septic Extensor Tenosynovitis of the Wrist Sonographic Appearances

Gonococcal infection may disseminate systemically, including involvement of the musculoskeletal system. 1-7 It has been estimated that gonococcal arthritis occurs in about 1% of patients with gonococcal infection. 6 Clinical manifestations of disseminated gonococcal infection include skin lesions, arthritis affecting 1 or more joints, and tenosynovitis or periarthritis particularly affecting the dorsum of the wrist and hand and also the ankles. 1 The primary site of infection may be asymptomatic. 1 We present a case of a young female patient with septic wrist extensor tenosynovitis and shoulder arthritis that was diagnosed after sonographic examination.