Does Scapular Stabilization Benefit Children with Obstetric Brachial Plexus Palsy?
A retrospective review suggests scapular stabilization procedures can improve range of motion and scapular dimensions. However, the clinical significance of improved scapular dimensions is yet to be determined.
Surya Mundluru, MD, and Alice Chu, MD
Terzis JK, Karypidis D, Mendoza R, Kokkalis ZT, Diawara N. Morphometric analysis of the effect of scapula stabilization on obstetric brachial plexus paralysis patients. HAND. 2014;9(3):303-314. doi:10.1007/s11552-014-9640-z.
The authors of this article sought to determine whether scapular stabilization in patients with obstetric brachial plexus paralysis truly restores anatomic position and enhances shoulder function.
The paper is a retrospective chart review from 1979 to 2007. Sixty-eight patients (41 female, 27 male) were included in the study. Of those patients, 38 had global paralysis, 13 had Erb’s paralysis with C7 involvement, and 18 patients the lesion was limited to C5 and C6. Mean age at presentation was 6.3 +/- 3.72 years.
X-ray dimensions were manually measured at several stages; outcomes of shoulder abduction and shoulder external rotation were also recorded. Group A included patients who underwent scapular stabilization procedure with or without adjunct shoulder procedure, and Group B included patients who underwent only secondary shoulder procedures with no stabilization component.
Scapular stabilization procedures included contralateral trapezius and/or rhomboid/ latissimus dorsi transfer. Secondary/adjunct surgeries included:
- Pedicle muscle transfers
- Free muscle transfers
- Joint contracture releases
- Latissimus dorsi/teres major rerouting
- Rotational osteotomies
Four dimensions of both scapulae in each patient were manually measured in posteroanterior and lateral X-rays using a standard protocol for all patients. These measurements – including scapular lateral border height (H), medial border length (O), large width (including acromion to lateral margin: W), and small width (glenoid to the lateral edge: w) – were converted into ratios. The ratio was created by dividing the dimensions of the paralyzed side by the dimensions of the unaffected side.
Shoulder abduction and external rotation were measured for each patient as well. All parameters were assessed before and after surgery.
Mean overall improvement was 85.68° for shoulder abduction and 36.74° for external rotation of the shoulder. Shoulder abduction and external rotation were significantly improved in patients who underwent scapular stabilization (mean of 9.15° more abduction, and 8.54° more external rotation) compared with those that did not undergo scapular stabilization (P < 0.05).
Improvement was noted in all scapular dimensions in all groups postoperatively. However, the mean improvements in H, W, w, and O were 4.92%, 14.04%, 12.66%, and 13.89% higher, respectively, in patients who underwent scapular stabilization than in those who did not undergo the procedure.
Obstetric brachial plexus palsy occurs in 0.1% to 0.4% of live births. Although the initial mainstay of treatment after birth is observation, once it is determined that the condition will not resolve, operative interventions have been utilized to augment and supplement patient function.
This study not only shows that scapular stabilization procedures are efficacious from the standpoint of functional range of motion, but that they are also correlated with improvement in scapular dimensions in the post-surgical period. Although the clinical relevance of this is yet to be determined, there is some literature to support that normal scapular dimensions correlate with optimum functional results.
There are limitations to this study, including heterogeneity of the patient population (global paralysis, Erb’s palsy, C5 and C6 lesions) and in the types of secondary surgeries performed. As mentioned before, scapular dimension and its exact clinical significance is yet to be determined. The patient population in this study is mostly female, thus questioning the generalizability of the results to the typical practice population.
Additionally, one assumes that the surgeons involved in the study have improved their surgical skill over time. Improved technology in the operating room or other cofounders may also have played a role in the findings.
Overall, scapular stabilization procedures appear to be an effective strategy in the treatment of obstetric brachial plexus paralysis. Future prospective-randomized studies will be needed to clarify its utility.
Surya Mundluru, MD, is a Resident, Division of Orthopedics, at NYU Langone Medical Center – Hospital for Joint Diseases, New York, New York. Alice Chu, MD, is an Assistant Professor of Orthopaedic Surgery, Division of Pediatric Orthopaedics, at NYU Langone Medical Center – Hospital for Joint Diseases, New York, New York.