Radiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

DOI: 10.1148/radiol.2313021057
This Article
Right arrow Abstract Freely available
Right arrow Figures Only
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kon, D. S.
Right arrow Articles by Kosco, A. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kon, D. S.
Right arrow Articles by Kosco, A. E.
(Radiology 2004;231:791-795.)
© RSNA, 2004

Pediatric Imaging

Glenohumeral Deformity in Children with Internal Rotation Contractures Secondary to Brachial Plexus Birth Palsy: Intraoperative Arthrographic Classification1

Darissa S. Kon, MD, Ani B. Darakjian, MD, Michael L. Pearl, MD and Anne E. Kosco, MD

1 From the Department of Diagnostic Imaging, Kaiser Permanente Los Angeles Medical Center, Los Angeles, Calif. From the 1999 RSNA scientific assembly. Received August 26, 2002; revision requested October 24; final revision received November 17, 2003; accepted January 5, 2004. Address correspondence to D.S.K., Department of Radiology, USC Medical Center, 1200 N State St, Suite 3550, Los Angeles, CA 90033 (e-mail: darissa@juno.com).


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
PURPOSE: To evaluate, with intraoperative arthrography, joint morphology in children undergoing surgical treatment of residual paralysis of the shoulder resulting in brachial plexus birth palsy and to correlate the morphology with the degree of passive external rotation.

MATERIALS AND METHODS: In 64 children (age range, 7 months to 13 years 6 months), an orthopedic surgeon performed intraoperative arthrography and measured passive external rotation while the patient received a general anesthetic. The orthopedic surgeon and three radiologists reviewed arthrograms and in consensus classified glenohumeral joints in one of four categories: concentric, with the humeral head well centered on the glenoid fossa; flat, with flattening of the posterior glenoid; biconcave, with the humeral head in articulation with the posterior of two concavities, which were in the same plane; and pseudoglenoid, with the humeral head in articulation with the more posterior of two concavities, with retroversion and in a plane different from that of the anterior concavity. Kruskal-Wallis test was used to compare preoperative external rotation with four appearances of glenoid.

RESULTS: Twenty-one children had concentric glenohumeral joints; seven children, flat glenohumeral joints; 19 children, biconcave glenoid; and 17 children, pseudoglenoid. Median passive external rotation was –20° for patients with pseudoglenoid, –10° for those with flat or biconcave glenoids, and 0° for those with concentric glenoids. Presence and type of glenoid deformity were significantly associated with severity of internal rotation contracture (P < .001).

CONCLUSION: Consistent patterns of glenohumeral joint deformity in brachial plexus birth palsy were identified and correlated with severity of internal rotation contracture.

© RSNA, 2004

Index terms: Brachial plexus, 276.492 • Children, skeletal system, 41.42 • Infants, skeletal system, 41.42 • Shoulder, abnormalities, 41.42 • Shoulder, arthrography, 41.122


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
Approximately three of 1,000 births result in trauma to the brachial plexus and lead to brachial plexus birth palsy. Ninety percent of infants recover fully or attain near normal function (1,2). The majority of the remaining 10% of infants, however, have persistent paralysis, which leads to internal rotation contractures associated with deformity and subluxation of the glenohumeral joint. The internal rotation contracture is caused by an imbalance in muscle strength, and the external rotator muscles (most clinically important, the infraspinatus muscle) are weaker than the internal rotator muscles (most clinically important, the subscapularis muscle). There is no agreement about the timing and type of surgical treatment that is recommended, perhaps because of the lack of sufficient detail in regard to the anatomy of the glenoid. Types of procedures include the release of tight anterior structures, such as subscapularis muscle, pectoralis major and minor muscles, and/or anterior capsule with or without latissimus dorsi muscle transfer for augmentation of external rotation and for relocation of the humeral head (3,4).

Several authors (5–7) documented the presence of glenohumeral joint deformities in association with internal rotation contractures. The morphology of these deformities, however, has only recently been characterized and classified by using arthrography.

Further characterization of these deformities is important because in the past surgical intervention and decision making were based on only the existence of the deformity (8). Although radiography often has been used in the assessment of the glenohumeral joint, it does not accurately depict cartilaginous changes. Therefore, other modalities, such as arthrography or magnetic resonance (MR) imaging, are needed for more accurate visualization of the morphology of the unossified glenoid. The purpose of our study was to evaluate, with intraoperative arthrography, joint morphology in children who were undergoing surgical treatment of residual paralysis of the shoulder that resulted from brachial plexus birth palsy and to correlate the morphology with the degree of passive external rotation.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
Patients
Sixty-four consecutive children who had internal rotation contracture and residual paresis secondary to brachial plexus birth palsy underwent surgery between July 1992 and November 2000. There were 33 boys and 31 girls ranging in age from 7 months to 13 years 6 months, with a mean age of 3 years 11 months. There was no significant difference between the sexes in numbers of cases according to age. The goal of surgery was to release the contracture and restore external rotation strength. Preoperative radiographs did not adequately demonstrate the predominantly unossified glenohumeral joint. We chose intraoperative arthrography to evaluate the morphology of the joint to avoid a second sedation procedure, such as for MR imaging or computed tomographic (CT) arthrography.

The protocol for the study was approved by the institutional review board of the Southern California Permanente Medical Group. Informed consent was obtained from the parents of the children.

Intraoperative Arthrography
Intraoperative arthrography (Orca Mini; Lunar GE Medical, Madison, Wis) was performed by the orthopedic surgeon (M.L.P.) with the patient receiving a general anesthetic immediately prior to surgery. With image intensification, a 20-gauge needle was inserted into the glenohumeral joint, and 4–6 mL of 50% each of diatrizoate sodium and diatrizoate meglumine (Renografin 60; Bracco Diagnostics, Princton, NJ) was injected. Three arthrographic (one anteroposterior and two axillary) images were obtained. One axillary view was obtained with the shoulder in 90° abduction, and the other was obtained with it in 60° abduction and 45° flexion.

Image Evaluation
The position of the humeral head relative to the glenoid and the shape of the glenoid were evaluated on the axillary views. Three radiologists (D.S.K., A.B.D., A.E.K.) and an orthopedic surgeon reviewed the images, and in consensus, they classified joints in each patient in one of the following four glenohumeral joint categories: concentric, flat, biconcave, and pseudoglenoid, with the appearance ranging from normal to severely deformed. The glenohumeral joint was classified as concentric when the humeral head was round and well centered on a glenoid with a matching curve. The glenoid was classified as flat when it showed loss of the normal curvature, with the humeral head in articulation with the posterior aspect of the flattened surface. In some children, the glenoid appeared flat on one axillary view but biconcave on another; it was considered flat only if it appeared so in both axillary projections. The glenoid was classified as biconcave when there were two concavities in the same plane, with the humeral head in articulation with the more posterior of the two glenoid concavities. The glenoid was classified as pseudoglenoid when the humeral head was in articulation with a posterior concavity with retroversion and when it was in a different plane from that of the original articular surface.

Passive external rotation was also measured intraoperatively by the same orthopedic surgeon prior to arthrography. With the child in a supine position on the operating table, the elbow was placed in 90° flexion. The shoulder was then rotated externally, and the degree of rotation was assessed by using the following scale: score of +90, full external rotation; score of 0, position of a handshake (perpendicular to the plane of the body); and score of –90, complete absence of external rotation.

At surgery, the extraarticular subscapularis muscle was released, with or without transfer of the latissimus dorsi muscle. Therefore, there was no direct visualization of the shape of the glenoid during surgery, and comparison with the arthrographic findings was not possible.

Statistical Analysis
The relevant continuous variables were not normally distributed in this sample, so we used nonparametric methods to analyze the results. The demographic results are presented as the median and range for the continuous variables and as counts for the categoric variables unless otherwise stated. The Kruskal-Wallis test was used to compare the two continuous variables (age group of the patient and preoperative passive external rotation) with respect to the four categories of appearance of the glenoid (appearance ranged from a normal to a severely deformed glenoid). Association was tested by using the Kendall {tau}-b rank correlation. We used software (SAS, version 8.2; SAS Institute, Cary, NC) for our statistical analyses. All analyses were two-tailed. Type I error was set at the .05 level.


   RESULTS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
DISCUSSION
 REFERENCES
 
Four types of joints were identified: concentric (21 children) (Fig 1), flat (seven children), biconcave (19 children), and pseudoglenoid (17 children).



View larger version (95K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 1a. Normal concentric glenohumeral joint in 10-month-old boy. A = acromion, C = coracoid process, G = glenoid, H = humeral head. (a) Axillary radiograph shows that humeral head and glenoid consist mainly of unossified cartilage, which is not visualized. (b) Axillary arthrogram. Top: With line tracing. Bottom: Without line tracing.

 


View larger version (138K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 1b. Normal concentric glenohumeral joint in 10-month-old boy. A = acromion, C = coracoid process, G = glenoid, H = humeral head. (a) Axillary radiograph shows that humeral head and glenoid consist mainly of unossified cartilage, which is not visualized. (b) Axillary arthrogram. Top: With line tracing. Bottom: Without line tracing.

 
Forty-three children had a deformity of the posterior aspect of the glenoid. There were three consistent patterns of posterior glenoid deformities. Seven children had flattening of the posterior aspect of the glenoid, with the humeral head centered on the glenoid (Fig 2). Nineteen children had a biconcave glenoid (Fig 3) in which there were two concavities in the same plane. Seventeen children had a pseudoglenoid, the most severe deformity (Fig 4) in which there were two concavities in different planes with retroversion of the more posterior concavity. In both the biconcave and pseudoglenoid patterns, the humeral head was in articulation with the posterior concavity.



View larger version (87K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 2. Axillary arthrograms show flat glenoid in 8-month-old boy. Relative alignment of humerus and scapula suggest posterior positioning of humeral head (H) on flattened glenoid (G). Top: With line tracing. Bottom: Without line tracing.

 


View larger version (138K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 3. Axillary arthrograms show biconcave glenoid (G) in 16-month-old girl. Relative alignment of humerus and scapula suggests that humeral head (H) articulates with posterior of two concavities in same plane. Top: With line tracing. Bottom: Without line tracing.

 


View larger version (89K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 4a. Pseudoglenoid (PG) in 6-year-old boy. A = acromion, C = coracoid process, G = glenoid, H = humeral head. (a) Axillary radiograph shows humeral head in articulation with posterior of two concavities. Concavity shows retroversion and is in a different plane from that of anterior concavity. Child is old enough for anatomy to be visualized without injection of contrast material. (b) Axillary arthrograms show humeral head with articulation with pseudoglenoid, which shows retroversion. Top: With line tracing. Bottom: Without line tracing.

 


View larger version (106K):
[in this window]
[in a new window]
[Download PPT slide]
  		Figure 4b. Pseudoglenoid (PG) in 6-year-old boy. A = acromion, C = coracoid process, G = glenoid, H = humeral head. (a) Axillary radiograph shows humeral head in articulation with posterior of two concavities. Concavity shows retroversion and is in a different plane from that of anterior concavity. Child is old enough for anatomy to be visualized without injection of contrast material. (b) Axillary arthrograms show humeral head with articulation with pseudoglenoid, which shows retroversion. Top: With line tracing. Bottom: Without line tracing.

 
The presence and type of glenoid deformity was significantly associated with the severity of the internal rotation contracture (P < .001) (Table 1). No such association could be shown between the severity of the internal rotation contracture and age. No patient with a preoperative external rotation greater than 0° had a joint deformity, and none of the patients with a preoperative external rotation less than –30° had a normal joint (Table 2). Before surgery, the median passive external rotation in these patients was –20° for patients with a pseudoglenoid, –10° for those with a flat or biconcave glenoid, and 0° for those with a concentric glenoid.


View this table:
[in this window]
[in a new window]

  		TABLE 1. Nonparametric Analysis of Preoperative External Rotation according to Glenoid Type

 

View this table:
[in this window]
[in a new window]

  		TABLE 2. Glenohumeral Joint Type, Age, and Preoperative External Rotation

 

   DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
REFERENCES
 
To our knowledge, there are few studies in the literature in which glenohumeral joint morphology is documented in children with internal rotation contracture secondary to brachial plexus birth palsy. Investigators in one case report (9) described a 4-month-old infant who had posterior dislocation of the glenohumeral joint with internal rotation, which was depicted at arthrography. Researchers in another study (5,10) described changes in the posterior glenoid at MR imaging in five patients. The changes included damage to the posterior articular labrum, blunting of the posterior corner, thinning of the posterior articular cartilage, and subluxation of the joint.

In another study, Waters et al (11) used MR imaging and CT to classify and subcategorize glenohumeral joint deformities into seven types in patients with brachial plexus birth palsy.

In the present study, we used intraoperative arthrographic images obtained in children with brachial plexus birth palsy to classify glenohumeral joint morphology into four distinct groups: concentric glenoid, flat glenoid, biconcave glenoid, and pseudoglenoid. Findings of our study also reveal a significant association between the severity of the internal rotation contracture and the severity of the glenoid deformity (P < .001) (Table 1).

It is hypothesized that an internal rotation contracture would apply a posteriorly directed force on the humeral head, as the soft tissues tighten anteriorly, and would thus result in a posterior displacement of the humeral head (12). This would, in turn, affect the shape of the posterior glenoid by either eroding it or inhibiting its development. Ultimately, a pseudoglenoid might form, and this formation is analogous to the formation of a pseudoacetabulum in congenital hip dysplasia (13). This hypothesis is supported by the study findings of Harryman et al (14) who, with a cadaver model, showed that tightening of the glenohumeral joint capsule causes a force on the humeral head away from the capsule.

It should be noted, however, that the presence of an internal rotation contracture is not necessarily predictive of the presence of a glenoid deformity on images. Thirty-four percent (21 of 64) of patients in this study had concentric glenohumeral joints. This was also noted in the study of Waters et al (11), in which 14% of patients with internal rotation contractures had normal glenoids at radiography and 30% of patients had only minimal deformities. Therefore, factors other than the presence of a contracture must contribute to the development of the glenoid in these patients. These factors may include possible partial denervation of some of the rotator cuff muscles. The strength of these muscles is difficult to assess at physical examination in infants.

Various surgical procedures have been recommended for the treatment of children with brachial plexus birth palsy. These include neurolysis, end-to-end nerve repair, nerve grafting, muscle transfer and muscle lengthening for late deformity, and humeral derotational osteotomy (3,4,8,15–18). These recommendations often have been widely divergent. This divergence may in part be caused by the fact that sufficient detail in regard to the anatomy of the glenoid was unavailable on radiographs. In addition, without knowledge of the shape of the glenoid, it was difficult to compare the outcomes of the various surgical procedures.

We believe that clarification of the shape of the deformed glenoid at arthrography or MR imaging in patients with brachial plexus birth palsy will provide an anatomic basis for the planning of surgical procedures and for the performance of outcome comparisons. Further studies with arthrography or MR imaging are needed to correlate the extent of glenoid deformity on preoperative images with the ultimate outcome of surgical interventions. There is ongoing research in this area at our institution.


   ACKNOWLEDGMENTS
 
Raoul J. Burchette, MA, MS, senior data consultant (statistician), Research and Evaluation, Regional Offices, and Robert J. Turko, Multimedia Communications, Kaiser Permanente, provided assistance in the preparation of this manuscript.


   FOOTNOTES
 
Author contributions: Guarantors of integrity of entire study, D.S.K., A.B.D., A.E.K.; study concepts, M.L.P., D.S.K.; study design, D.S.K., M.L.P., A.B.D.; literature research, D.S.K., M.L.P., A.B.D.; clinical studies, M.L.P., D.S.K.; data acquisition, all authors; data analysis/interpretation, D.S.K., M.L.P.; statistical analysis, D.S.K., M.L.P.; manuscript preparation, D.S.K.; manuscript definition of intellectual content, editing, and revision/review, D.S.K., A.B.D., A.E.K.; manuscript final version approval, D.S.K.


   REFERENCES
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 

  1. Greenwald AG, Schute PC, Shiveley JL. Brachial plexus birth palsy: a 10-year report on the incidence and prognosis. J Pediatr Orthop 1984; 4:689-692.[Medline]
  2. Michelow BJ, Clarke HM, Curtis CG, Zuker RM, Seifu Y, Andrews DF. The natural history of obstetrical brachial plexus birth palsy. Plast Reconstr Surg 1994; 93:675-680.[Medline]
  3. Gilbert A, Brockman R, Carlioz H. Surgical treatment of brachial plexus birth palsy. Clin Orthop 1991; 264:39-47.
  4. Gilbert A, Romana C, Ayatti R. Tendon transfers for shoulder paralysis in children. Hand Clin 1988; 4:633-642.[Medline]
  5. Gudinchet F, Maeder P, Oberson JC, Schnyder P. Magnetic resonance imaging of the shoulder in children with brachial plexus birth palsy. Pediatr Radiol 1995; 25(suppl 1):S125-S128.
  6. Hernandez RJ, Dias L. CT evaluation of the shoulder in children with Erb’s palsy. Pediatr Radiol 1988; 18:333-336.[CrossRef][Medline]
  7. Troum S, Floyd WE, III, Waters PM. Posterior dislocation of the humeral head in infancy associated with obstetrical paralysis: a case report. J Bone Joint Surg Am 1993; 75:1370-1375.[Free Full Text]
  8. Zancolli EA, Zancolli ER, Jr. Palliative surgical procedures in sequelae of obstetrical palsy. Hand Clin 1988; 4:643-669.[Medline]
  9. White SJ, Blane CE, DiPietro MA, Kling TF, Jr, Hensinger RN. Arthrography in evaluation of birth injuries of the shoulder. Can Assoc Radiol J 1987; 38:113-115.[Medline]
  10. Gudinchet F, Naggar L, Ginalski JM, Dutoit M, Schnyder P. Magnetic resonance imaging of the shoulder in children. Skeletal Radiol 1992; 21:19-21.[Medline]
  11. Waters PM, Smith GR, Jaramillo D. Glenohumeral deformity secondary to brachial plexus birth palsy. J Bone Joint Surg Am 1998; 80:668-677.[Abstract/Free Full Text]
  12. Bigliani LU, Flatow EL, Kelkar R, et al. The effect of anterior capsular tightening on shoulder kinematics and contact (abstr). J Shoulder Elbow Surg 1994; 3:S65.
  13. Lafferty CM, Sartoris DJ, Tyson R, et al. Acetabular alterations in untreated congenital dysplasia of the hip: computed tomography with multiplanar reformation and three-dimensional analysis. J Comput Assist Tomogr 1986; 10:84-89.[Medline]
  14. Harryman DT, 2nd, Sidles JA, Clark JM, McQuade KJ, Gibb TD, Matsen FA, 3rd. Translation of the humeral head on the glenoid with passive glenohumeral motion. J Bone Joint Surg Am 1990; 72:1334-1343.[Abstract/Free Full Text]
  15. Gilbert A, Razaboni R, Amar-Khodja S. Indications and results of brachial plexus surgery in obstetrical palsy. Orthop Clin North Am 1988; 19:91-105.[Medline]
  16. Narakas AO. Muscle transpositions in the shoulder and upper arm from sequelae of brachial plexus birth palsy. Clin Neurol Neurosurg 1993; 95(suppl):S89-S91.
  17. Phipps GJ, Hoffer MM. Latissimus dorsi and teres major transfer to rotator cuff for Erb’s palsy. J Shoulder Elbow Surg 1995; 4:124-129.[CrossRef][Medline]
  18. Tachdjian MO. Pediatric orthopedics 2nd ed. Vol 3. Philadelphia, Pa: Saunders, 1990; 2027-2052.



This article has been cited by other articles:


Home page
 J Bone Joint Surg BrHome page
R. K. Nath and X. Liu
Nerve reconstruction in patients with obstetric brachial plexus injury results in worsening of glenohumeral deformity: A CASE-CONTROL STUDY OF 75 PATIENTS
J Bone Joint Surg Br, May 1, 2009; 91-B(5): 649 - 654.
[Abstract] [Full Text] [PDF]

Home page
 J Am Acad Orthop SurgHome page
M. L. Pearl
Shoulder Problems in Children With Brachial Plexus Birth Palsy: Evaluation and Management
J. Am. Acad. Ortho. Surg., April 1, 2009; 17(4): 242 - 254.
[Abstract] [Full Text] [PDF]

Home page
 JBJSHome page
M. L. Pearl, B. W. Edgerton, P. A. Kazimiroff, R. J. Burchette, and K. Wong
Arthroscopic Release and Latissimus Dorsi Transfer for Shoulder Internal Rotation Contractures and Glenohumeral Deformity Secondary to Brachial Plexus Birth Palsy
J. Bone Joint Surg. Am., March 1, 2006; 88(3): 564 - 574.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Figures Only
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kon, D. S.
Right arrow Articles by Kosco, A. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kon, D. S.
Right arrow Articles by Kosco, A. E.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
RADIOLOGY RADIOGRAPHICS RSNA JOURNALS ONLINE