Biomedical subjects

Dennis W Rivenburgh

Publications and source records attributed to Dennis W Rivenburgh.

2 recordsLinked to original sources

PubMed2004

Mobile superior glenoid labrum: a normal variant or pathologic condition?

BACKGROUND: Arthroscopic differentiation between a pathologic superior labrum anterior posterior lesion and a normal anatomic variant may be difficult. HYPOTHESIS: Various anatomic patterns exist that systematically characterize superior biceps-labral configurations. One variant involves a mobile superior labrum with exposed articular cartilage on the superior glenoid tubercle. The authors seek to demonstrate that this is nonpathologic. STUDY DESIGN: A prospective, consecutive descriptive anatomic study with 1-year clinical follow-up of a subgroup with an identified mobile superior labrum. METHODS: A total of 191 consecutive patients were prospectively evaluated arthroscopically to quantify the dimensions of the labrum and articular cartilage on the supraglenoid tubercle. RESULTS: A subgroup of 49 patients was identified with articular cartilage on the supraglenoid tubercle, a mobile labrum, and no fibrous tearing or evident injury in this region. In postoperative follow-up, only 1 (2.0%) of these patients was clinically symptomatic in the region of the superior labrum-biceps origin. CONCLUSIONS: Indication for repair of a mobile superior glenoid labrum must be carefully addressed in the context of normal anatomic morphologic variability. The labral and supraglenoid tubercle morphology was noted to be highly variable. CLINICAL RELEVANCE: Patients with mobile labral tissue overlying intact articular cartilage, and no evidence of trauma, are not candidates for repair.

Adult↗

PubMedDate not supplied

The 7-o'clock posteroinferior portal for shoulder arthroscopy.

BACKGROUND: Access to the inferior glenohumeral joint of the shoulder is very limited through the traditional 2- or 3-o'clock anterior portals. HYPOTHESIS: The 7-o'clock posteroinferior portal offers an excellent alternative approach. STUDY DESIGN: Descriptive anatomic study. METHODS: Six paired cadaveric shoulders were used to arthroscopically develop and test a 7-o'clock posteroinferior portal. The distances between the portal and the subscapular and axillary nerves were measured with the arm in six different positions, combining flexion, extension, abduction, and adduction. RESULTS: The distance from the 7-o'clock posteroinferior portal to the axillary nerve was 39 +/- 4 mm and to the suprascapular nerve was 28 +/- 2 mm. There was no statistically significant nerve-to-portal differential distance when the arm was placed in flexion, extension, abduction, or adduction. The inside-to-outside technique produced a 7-o'clock posteroinferior portal approximately 5 mm further from both the axillary and suprascapular nerves than did the outside-to-inside method. The angle of divergence from the 7-o'clock posterior portal skin incision to the axillary nerve was 47 degrees and to the suprascapular nerve was 33 degrees. CONCLUSIONS: The 7-o'clock portal affords safe, direct working access to the inferior capsular recess of the glenohumeral joint. CLINICAL RELEVANCE: The 7-o'clock portal is a safe and effective technique for use by shoulder surgeons.

Arthroscopy↗