Yuko Nakashima

HIGH-RESOLUTION ULTRASONOGRAPHIC EVALUATION OF ''HOURGLASS-LIKE FASCICULAR CONSTRICTION'' IN PERIPHERAL NERVES: A PRELIMINARY REPORT

An hourglass-like constriction is a focal fascicular lesion observed in one or a few places in one or a few fascicles of a peripheral nerve trunk, and usually affects the anterior interosseous (AIN) or posterior interosseous (PIN) nerve. Constrictions have previously been discovered only by surgical exploration, and have been unable to be recognized on pre-operative imaging. We encountered some cases in which the lesion was able to be diagnosed pre-operatively by high-resolution ultrasonography; these findings were then confirmed intra-operatively. Five consecutive cases were included in this study. In three cases with constrictions revealed on pre-operative ultrasound, the findings were confirmed intra-operatively. In the remaining two cases in which no constrictions were detected pre-operatively, no constriction was revealed intra-operatively. High-resolution ultrasonography may play a significant role in the diagnosis of hourglass-like constrictions, and may thus lead to significant changes in treatment strategies for AIN and PIN palsy.

Use of quantitative intra-operative electrodiagnosis during partial ulnar nerve transfer to restore elbow flexion: THE TREATMENT OF EIGHT PATIENTS FOLLOWING A BRACHIAL PLEXUS INJURY

The transfer of part of the ulnar nerve to the musculocutaneous nerve, first described by Oberlin, can restore flexion of the elbow following brachial plexus injury. In this study we evaluated the additional benefits and effectiveness of quantitative electrodiagnosis to select a donor fascicle. Eight patients who had undergone transfer of a simple fascicle of the ulnar nerve to the motor branch of the musculocutaneous nerve were evaluated. In two early patients electrodiagnosis had not been used. In the remaining six patients, however, all fascicles of the ulnar nerve were separated and electrodiagnosis was performed after stimulation with a commercially available electromyographic system. In these procedures, recording electrodes were placed in flexor carpi ulnaris and the first dorsal interosseous. A single fascicle in the flexor carpi ulnaris in which a high amplitude had been recorded was selected as a donor and transferred to the musculocutaneous nerve. In the two patients who had not undergone electrodiagnosis, the recovery of biceps proved insufficient for normal use. Conversely, in the six patients in whom quantitative electrodiagnosis was used, elbow flexion recovered to an M4 level. Quantitative intra-operative electrodiagnosis is an effective method of selecting a favourable donor fascicle during the Oberlin procedure. Moreover, fascicles showing a high-amplitude in reading flexor carpi ulnaris are donor nerves that can restore normal elbow flexion without intrinsic loss.

Comparative study on the effectiveness of corticosteroid injections between trigger fingers with and without proximal interphalangeal joint flexion contracture

Trigger fingers with proximal interphalangeal joint flexion contracture are suggested to have a poorer response to corticosteroid injection than those without contracture, though this has not been proven scientifically. We compared the clinical response to corticosteroid injection between trigger fingers with and without proximal interphalangeal joint contracture, and investigated the influence of the injection on the A1 pulley and flexor digitorum tendons using ultrasonography. One month after injection, pain was significantly reduced in the no contracture group, and 56% of trigger fingers with proximal interphalangeal joint contracture resolved. Before injection, relative thickening of the A1 pulley and flexor digitorum tendons, and a partial hypoechoic lesion of the flexor digitorum superficialis tendon were observed in the contracture group. One month after injection, the thickening of the tendons and the A1 pulley was reduced, but the partial hypoechoic lesion was still observed in significant numbers. We have demonstrated that the presence of a proximal interphalangeal joint contracture was associated with a reduced clinical response to corticosteroid injection, and we suggest that the pathologic change in the flexor digitorum superficialis tendon, represented by the partial hypoechoic lesion, contributed to corticosteroid injection resistance. Level of evidence: IV

Correlation between “hourglass‐like fascicular constriction” and idiopathic anterior interosseous nerve palsy

Introduction: In recent operative cases of anterior interosseous nerve palsy (AINP), hourglass‐like fascicular constrictions have been reported. We prospectively investigated the ultrasonographic history of these lesions to better understand the role of this lesion in AINP. Methods: Seven patients who were diagnosed with idiopathic AINP based on classic clinical findings and had hourglass‐like fascicular constrictions found on ultrasonography were included. All but 1 patient selected surgery, and we followed up all patients clinically and with ultrasonography. Results: In the 5 patients treated surgically in whom paralysis recovered to a level greater than M4, postoperative ultrasonography revealed less constriction. The other patient experienced little recovery after surgery, and the severe constriction remained. In a conservatively treated patient, the paralysis recovered completely, and upon ultrasonography, the constriction had lessened. Conclusions: Although the mechanism is still unknown, hourglass‐like fascicular constriction lessened with relief of motor weakness both in operatively and conservatively treated patients. Muscle Nerve 55: 508–512, 2017

Slow progressive popliteal artery insufficiency after neglected proximal tibial physeal fracture: a case report.

Popliteal artery injury is most commonly associated with high-energy trauma, which is easily diagnosed upon initial physical examination. However, in some situations, the diagnosis of arterial injury is delayed because of slow progression of arterial insufficiency, which may lead to limb amputation. We report a rare case of popliteal arterial occlusion with the presence of arterial pulses during initial assessment, resulting from a neglected proximal ibial physis fracture. This case shows that even in the presence of foot pulses, the surgeon must consider the possibility of a popliteal artery damage whenever trauma is seen near the knee joint.

Spontaneous recovery of a case with suspected hourglass-like fascicular constriction and anterior interosseous nerve palsy.

en neurofibroma by Lazarus and Trombetta in 1978. The aetiology and natural history of this nerve tumour remains unclear. Previous studies suggested that a perineurioma might be a reaction to compression or trauma. However, other studies suggest a neoplastic disease since a chromosomal 22 deletion was identified (Emory et al., 1995). Intraneural perineurioma usually presents as a painless mononeuropathy with progressive motor weakness. Sensory involvement is uncommon. Intraneural perineurioma is most prevalent in young adults and the upper extremities are affected most commonly (Cortes et al., 2005). However, there is only one case reported involving a digital nerve (Emory et al., 1995). Although magnetic resonance imaging is a valuable method in identifying soft tissue tumours and nerve sheath tumours, there is a lack of specificity. Magnetic resonance imaging findings of intraneural perineuriomas are nonspecific. Biopsy is necessary to establish a definitive diagnosis. The treatment of intraneural perineurioma remains controversial: a conservative approach is usually justified as these tumours are benign and slowly progressive, however surgery is recommended in patients with neurological or functional deficits. Resection with graft repair, intraneural neurolysis and nerve transfers have been described. Since there is a large variety in presentation and localization, each case needs to be discussed individually. In conclusion, an intraneural perineurioma is a benign peripheral nerve sheath tumour with an unknown natural history that is very rare in a digit. The type of treatment depends on clinical presentation and localization of the tumour. The radial digital nerve of the index finger has an important sensory function in pinch and tripod grip, which ideally should be preserved. However, in our opinion, resecting the entire digital nerve was the best treatment to solve the functional problems of the digit in this case. Conflict of interests

Comparison of sonography and MRI in the evaluation of stability of capitellar osteochondritis dissecans

To compare the diagnostic accuracies of ultrasonography (US) and magnetic resonance imaging (MRI) with intraoperative capitellar osteochondritis dissecans (COCD) fragment stability findings.

Novel sluggish speed signs on ultrasound is indicative of hemangiomas.

Background Hemangiomas are sometimes difficult to diagnose with current techniques. Sluggish speed signs (SSS) are a phenomenon that: (i) cannot be depicted as Doppler flow on Doppler ultrasound; (ii) can be observed as fluid movements on Doppler ultrasound; and (iii) cannot be depicted as waveforms on pulse Doppler mode. We hypothesized that SSS could be diagnostic indicators for hemangiomas. Purpose To evaluate whether ultrasound findings, in particular those relating to SSS, are a reliable tool for detecting hemangiomas compared to magnetic resonance imaging (MRI) and the gold standard for hemangioma diagnosis: pathological examination by biopsy or after surgical resection. Material and Methods Totally, 105 patients (mean age, 44.9 years) with soft-tissue tumors underwent MRI and ultrasound examination before biopsy or tumor resection. Ultrasound findings were compared with MRI as well as pathological findings, which were used as reference. Results Hemangiomas were identified in 16 (6.25%) of the 105 patients. On MRI, flow voids showed sensitivity and specificity values of 81.3% and 96.6%, respectively. On ultrasound examination, SSS was the only finding to show equally high sensitivity (93.8%) and specificity (96.6%) for diagnosing hemangiomas. There was no significant difference in the diagnostic capabilities between these two parameters (P = 0.479). Conclusion SSS showed a high sensitivity and specificity for diagnosing hemangiomas and therefore are useful diagnostic tools to supplement MRI.