Quantification of Humeral Head Deformity Following Neonatal Brachial Plexus Palsy
ABSTRACT Neonatal brachial plexus palsy frequently leads to glenohumeral dysplasia if neurological recovery is incomplete. Although glenoid retroversion and glenohumeral subluxation have been well characterized, humeral head deformity has not previously been quantified. Nonetheless, humeral head flattening is described as a contraindication to joint contracture release and external rotation tendon transfers. This study describes a novel technique for objectively quantifying humeral head deformity with use of magnetic resonance (MR) imaging and correlates the humeral head deformity with clinical and radiographic outcomes following joint rebalancing surgery.
Magnetic resonance images of thirty-two children (age, 0.7 to 11.5 years) with neonatal brachial plexus palsy were retrospectively reviewed. Passive shoulder external rotation and Mallet scores were reviewed before joint rebalancing surgery and at a minimum clinical follow-up interval of two years. The humeral head skewness ratio on preoperative and postoperative axial MR images was defined as the ratio of anterior to posterior humeral head area, and this ratio was compared between affected and unaffected shoulders and with the glenoid version angle, posterior subluxation of the humeral head, and clinical parameters before and after surgery with use of paired t tests and Spearman correlation. Intraobserver and interobserver reliability of MR image measurements was determined.
Measurements of the skewness ratio on the affected side had moderate to substantial intraobserver reliability (0.53 to 0.72) and substantial interobserver reliability (0.65 to 0.71). Preoperatively, the skewness ratio of the affected humeral head (mean, 0.76; range, 0.54 to 1.03) differed significantly from the ratio in the contralateral shoulder (p < 0.05) and was significantly associated with the glenoid version angle (p < 0.05) and posterior subluxation of the humeral head (p < 0.05). Remodeling of the affected humeral head was observed postoperatively, with a significant improvement in the skewness ratio (p < 0.05). However, there were no significant correlations between the preoperative skewness ratio and postoperative clinical outcomes.
Humeral head deformity in neonatal brachial plexus palsy correlated with other measures of glenohumeral dysplasia and could be reliably and objectively quantified on MR imaging with use of the skewness ratio. The humeral head deformity can remodel following joint rebalancing surgery, and such a deformity alone does not preclude a successful outcome after surgical attempts to restore glenohumeral congruity.
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ABSTRACT: Obstetrical brachial plexus palsy (OBPP) is a common birth injury, resulting in severe functional losses. Yet, little is known about how OBPP affects the 3-dimensional (3D) humeral morphology. Thus, the purpose of this study was to measure the 3D humeral architecture in children with unilateral OBPP. Thirteen individuals (4 female and 9 male patients; mean age, 11.8 ± 3.3 years; mean Mallet score, 15.1 ± 3.0) participated in this institutional review board approved study. A 3D T1-weighted gradient-recalled echo magnetic resonance image set was acquired for both upper limbs (involved and noninvolved). Humeral size, version, and inclination were quantified from 3D humeral models derived from these images. The involved humeral head was significantly less retroverted and in declination (medial humeral head pointed anteriorly and inferiorly) relative to the noninvolved side. Osseous atrophy was present in all 3 dimensions and affected the entire humerus. The inter-rater reliability was excellent (intraclass correlation coefficient, 0.96-1.00). This study showed that both humeral atrophy and bone shape deformities associated with OBPP are not limited to the axial plane but are 3D phenomena. Incorporating information related to these multi-planar, 3D humeral deformities into surgical planning could potentially improve functional outcomes after surgery. The documented reduction in retroversion is an osseous adaptation, which may help maintain glenohumeral congruency by partially compensating for the internal rotation of the arm. The humeral head declination is a novel finding and may be an important factor to consider when one is developing OBPP management strategies because it has been shown to lead to significant supraspinatus inefficiencies and increased required elevation forces.Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.] 11/2013; 23(5). DOI:10.1016/j.jse.2013.08.014 · 2.37 Impact Factor
Chapter: The Pediatric Upper Extremity[Show abstract] [Hide abstract]
ABSTRACT: The most common nerve injury in children is neonatal brachial plexus palsy (NBPP). NBPP is associated with significant upper extremity impairment and carries with it quality of life impact on the child as well as the entire family. The occurrence of NBPP in the United States is close to 1.5 per 1,000 live births. Thirty to forty percent of these children will suffer permanent upper extremity functional insufficiencies. NBPP is not a new finding. In the mid-1700s, a physician named William Smellie wrote about a child that presented face-first for delivery. Smellie carefully delivered the child using forceps and noted that the long time spent in the birth canal had rendered the child’s arms paralyzed for several days. By the mid-1800s, NBPP had become known as obstetrical palsy, relating the palsy to delivery. In the late 1800s, a physician named Wilhelm Heinrich Erb posed a significant breakthrough when he described the C5–C6 junction as a common area of injury for NBPP patients. This chapter reviews what might be accepted as the high points of the history and epidemiology of NBPP. Understanding the past allows us to appreciate where we are in the present, and it gives us greater ability to focus on the future. Great strides have been made in just the last decade. There have been significant advances made in virtually all facets of this injury, understanding its incidence and risk factors, basic science insight to bone and muscle growth abnormalities following nerve injury, as well as both primary and secondary surgical reconstructive treatment approaches. The multidimensional physical and psychological challenges of this patient population will continue to merit coordinated multispecialty care for some time to come.The Pediatric Upper Extremity, 01/2015: pages 589-605; , ISBN: 978-1-4614-8513-1