Muscle elasticity in patients with neonatal brachial plexus palsy using shear-wave ultrasound elastography. Preliminary results.

Ultrasound shear wave elastography (SWE) is a noninvasive, reliable and reproducible method, used for the qualitative and quantitative evaluation of tissues. The aim of this study was to compare muscle elasticity between the healthy and the involved sides in children with neonatal brachial plexus palsy (NBPP) using the elastography tool and to assess whether the difference was correlated with the Mallet grading system. We repeatedly measured the shear modulus coefficient of several muscles around the shoulder in stretched or passively relaxed positions on 14 patients. We evaluated the abductor muscles (supraspinatus and deltoid), the infraspinatus, the pectoralis major and the latissimus dorsi. We found a mean shear modulus significantly higher in most studied muscles in the pathologic side (P < 0.001), especially in the stretched position (P < 0.001). Moreover, the shear modulus increases with the degradation of the Mallet score for the abduction and external rotation tasks. SWE seems to be a reliable and reproducible tool to assess muscle elasticity in NBPP.

Screw Removal Can Resolve Unexplained Anterior Pain Without Recurrence of Shoulder Instability After Open Latarjet Procedures.

BACKGROUND: Anterior shoulder instability can be successfully treated using Latarjet procedures, although a small proportion of patients report unexplained pain. PURPOSE/HYPOTHESIS: The purpose was to report the prevalence and characteristics of patients with unexplained pain without recurrent instability after open Latarjet procedures and to determine whether screw removal can alleviate pain. The hypothesis was that unexplained pain without recurrent instability might be due to soft tissue impingements against the screw heads and that the removal of screws would alleviate or reduce pain. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We retrospectively reviewed the clinical and radiographic records of 461 consecutive shoulders treated by open Latarjet procedures for anterior instability between 2002 and 2014. Unexplained anterior pain was present in 21 shoulders (4.6%) and treated by screw removal at 29 ± 37 months (mean ± SD). Postoperative assessment at >12 months after screw removal included complications, visual analog scale for pain (pVAS), subjective shoulder value, Rowe score, Walch-Duplay score, and ranges of motion. The study cohort comprised the shoulders of 20 patients (9 women, 11 men) aged 25 ± 6 years (median, 25 years; range, 16-34 years) at screw removal and involved the dominant arm in 13 (62%) shoulders. RESULTS: Screw removal alleviated pain completely in 14 shoulders (67%; pVAS improvement, 6.4 ± 1.8; median, 6; range, 3-8) and reduced pain in the remaining 7 (33%; pVAS improvement, 2.4 ± 1.4; median, 2; range, 1-5). At 38 ± 23 months after screw removal, 2 recurrences of instability unrelated to screw removal occurred. The subjective shoulder value was 79% ± 22% (median, 90%; range, 0%-95%); Rowe score, 85 ± 20 (median, 95; range, 30-100); and Walch-Duplay score, 82 ± 19 (median, 85; range, 25-100). Mobility improved in active forward elevation (171°± 14°), external rotation with the elbow at the side (61°± 12°), and external rotation with the arm at 90° of abduction (67°± 13°) and especially in internal rotation, with only 2 shoulders (10%) limited to T12 spine segment. CONCLUSION: The present findings confirm that unexplained anterior pain after Latarjet procedures can be related to the screws used to fix bone blocks, which can safely be alleviated or reduced by screw removal.

Shoulder and elbow kinematics during the Mallet score in obstetrical brachial plexus palsy.

BACKGROUND: The physical signs of obstetrical brachial plexus palsy range from temporary upper-limb dysfunction to a lifelong impairment and deformity in one arm. The aim of this study was to analyze the kinematics of the upper limb and to evaluate the contribution of glenohumeral and scapulothoracic joints of obstetrical brachial plexus palsy children. METHODS: Six children participated in this study: 2 males and 4 females with a mean age of 11.7years. Three patients had a C5, C6 lesion and 3 had a C5, C6, C7 lesion. They were asked to perform five tasks based on the Mallet scale and the kinematic data were collected using the Fastrak electromagnetic tracking device. FINDINGS: The scapulothoracic protraction and posterior tilt were significantly increased in the involved limb during the hand to mouth task (p=0.006 and p=0.015 respectively). The scapulothoracic Protraction/glenohumeral Elevation ratio was significantly increased in the involved limb during the hand to neck task (p=0.041) and the elevation task (p=0.015). The ratios of scapulothoracic Tilt on the three glenohumeral excursion angles were significantly increased during the hand to mouth task (p≤0.041). The scapulothoracic Mediolateral/glenohumeral Elevation ratio was significantly increased in the involved limb during the elevation task (p=0.038). The glenohumeral elevation excursion was significantly decreased in the involved limb during the hand to neck task (p<0.001) and the elevation task (p=0.0003). INTERPRETATION: This study gives us information about the greater contribution of the scapulothoracic joint to shoulder motion for affected arm of obstetrical brachial plexus palsy patients compared to their unaffected arm. Kinematic analysis could be useful in shoulder motion evaluation during the Mallet score and to evaluate outcomes after surgery.