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Surgical normalization of the shoulder joint in obstetric brachial plexus injury
Rahul K Nath1, Abdelouahed Amrani, Sonya E Melcher
1Texas Nerve and Paralysis Institute, Houston, USA. drnath@drnathmedical.com
Insights
Triangle tilt surgery significantly improves shoulder anatomy in obstetric brachial plexus injuries (OBPI) patients. This procedure corrects bony derangements, reducing posterior subluxation and improving glenoid shape for better shoulder function.
Area of Science:
- Orthopedic surgery
- Pediatric orthopedics
- Brachial plexus injury research
Background:
- Obstetric brachial plexus injuries (OBPI) cause significant bony derangements, including posterior humeral head subluxation, glenoid retroversion, and incongruity.
- Scapular deformities like hypoplasia and abnormal rotation often accompany OBPI, worsening shoulder dysfunction.
Purpose of the Study:
- To evaluate the anatomical effects of triangle tilt surgery on the glenohumeral joint in patients with OBPI.
- To assess improvements in posterior subluxation, glenoid version, and glenoid shape following the surgical intervention.
Main Methods:
- The study analyzed 100 OBPI patients undergoing triangle tilt surgery.
- Pre- and post-operative imaging (CT and MRI) were used to measure anatomical changes over 12–38 months.
- The triangle tilt surgery aims to restore the distal acromioclavicular triangle to a neutral position.
Main Results:
- Significant improvements were observed in posterior subluxation and glenoid version post-surgery.
- The rate of complete posterior glenohumeral dislocation decreased from 19% preoperatively to 11% postoperatively.
- Glenoid shape improved, with 81% of patients showing concave or flat shapes after surgery compared to 53% before.
Conclusions:
- Triangle tilt surgery effectively repositions and remodels the glenohumeral joint in OBPI patients.
- The observed anatomical improvements suggest potential for enhanced shoulder function and quality of life.
Abstract:
Obstetric brachial plexus injuries (OBPI) result in bony derangements that include posterior humeral head subluxation, glenoid retroversion, and joint incongruity. Often these deformities are accompanied by scapular hypoplasia, elevation, and rotation, which further exacerbate shoulder dysfunction. The purpose of the current study was to investigate the effects of triangle tilt surgery on glenohumeral joint anatomy in 100 OBPI patients. The triangle tilt surgery restores the distal acromioclavicular triangle from an abnormal superiorly angled position to a neutral position, thereby restoring normal glenohumeral anatomic relationships.Axial computed tomography and magnetic resonance images taken before and 12- to 38-months after surgery showed significant improvements in both posterior subluxation and glenoid version. Patients with complete posterior glenohumeral dislocation improved from 19% preoperatively, to 11% postoperatively. Glenoid shape was also improved, with 81% of patients classified as concave or flat after surgery compared with 53% before surgery.Triangle tilt surgery allows for both repositioning and remodeling of the glenohumeral joint. These anatomic improvements after triangle tilt surgery hold promise for improving shoulder function and quality of life for OBPI patients.
