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Examination of Upper Extremity Length Discrepancy in Patients with Obstetric Brachial Plexus Paralysis
Murat Danisman1, Abdulsamet Emet2, Ismail Aykut Kocyigit2
1Department of Orthopedics and Traumatology, Faculty of Medicine, Giresun University, Giresun 28100, Turkey.
Insights
Obstetric brachial plexus palsy (OBPP) can cause arm length discrepancies. This study found significant differences in humerus, radius, and metacarpal lengths based on age and Narakas classification in affected limbs.
Area of Science:
- Orthopedics
- Pediatric Surgery
- Neurology
Background:
- Obstetric brachial plexus palsy (OBPP) presents variable natural courses and potential complications.
- Arm length discrepancies are a concern for children with OBPP managed in outpatient settings.
- Understanding limb length changes is crucial for effective OBPP management.
Purpose of the Study:
- To determine differences in the length of the affected upper extremity compared to the unaffected limb in children with OBPP.
- To analyze how age, Narakas classification, and surgical interventions influence limb length discrepancies.
Main Methods:
- A study included 45 patients aged 6 months to 18 years with unilateral obstetric brachial plexus palsy.
- Lengths of humerus, ulna, radius, 2nd metacarpal, and 5th metacarpal were measured on both affected and healthy sides.
- Data were analyzed based on gender, age, side, Narakas classification, and surgical history (primary and secondary).
Main Results:
- Statistically significant differences in affected/healthy length change rates were observed with age for humerus, radius, and metacarpals.
- Narakas classification significantly correlated with differing change rates in ulna, radius, and metacarpal lengths (p < 0.05).
- Secondary surgeries showed statistically significant differences in affected/healthy length change rates for ulna, radius, and metacarpals (p < 0.05).
Conclusions:
- Obstetric brachial plexus palsy can lead to joint/bone deformities and shortening during postnatal growth.
- Functional improvements in upper extremity musculature may help mitigate limb length discrepancies.
- Age and Narakas classification are key factors influencing limb length changes in OBPP patients.
Abstract:
Since the natural course of obstetric brachial plexus palsy is variable, several problems are encountered. One important question, in considering patients with OBPP under observation in outpatient clinical settings, is whether children will have length discrepancies in their arms. The aim of this study was to determine differences in the length of the affected extremity, in comparison to the opposite upper extremity. As such, 45 patients, aged 6 months to 18 years, with unilateral brachial plexus palsy developed due to obstetric reasons, were included in the study. Affected and healthy side humerus, ulna, radius, 2nd metacarpal and 5th metacarpal lengths were evaluated according to gender, age, side, Narakas classification, primary and secondary surgery. Statistically significant differences were found in the change rates of affected/healthy humerus, radius, 2nd metacarpal and 5th metacarpal lengths according to age (93%, 95%, 92%, 90% and 90%, respectively). Affected/healthy change rates of ulna, radius, 2nd metacarpal and 5th metacarpal lengths were found to differ statistically (p < 0.05) according to the Narakas classification variable (94%, 92%, 95%, 94% and 94%, respectively). There were no statistically significant differences in the ratios of affected/healthy change in the lengths of the humerus, ulna, radius and 5th metacarpal compared to the primary surgery (p > 0.05). The ratios of affected/healthy change in ulna, radius and 5th metacarpal lengths were found to differ statistically (p < 0.05) according to secondary surgeries (93%, 91%, 91% and 92%, respectively). Joint and bone deformities and bone shortening were observed after changes that occurred in the postnatal and growing periods due to obstetric brachial plexus palsy. Every increase in function to be gained in the upper extremity musculature was also potentially able to reduce problems, such as shortness.
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