Ultrasound of the normal canine supraspinatus tendon: comparison with gross anatomy and histology

BackgroundThis study aimed to compare the ultrasonographic and histological features of the supraspinatus tendon (ST) and its peculiar appearance in contrast with the biceps brachii tendon.MethodsFor this purpose, 19 non-lame dog cadavers were subjected to an ultrasonographic and histologic evaluation of both shoulders after postmortem examination.ResultsClose to their insertion on the greater tubercle, all STs displayed a widened portion with a deep central hypoechoic area lacking a fibrillar pattern, when compared with its more proximal aspect and adjacent biceps brachii. Histologically this deep portion corresponded to poorly organised collagen bundles interspersed within a myxoid substance mainly composed of mucopolysaccharides. This central myxoid area with collagen disarray was responsible for the reduced echogenicity on ultrasound.ConclusionThe focal widening of the ST insertion and its central mucopolysaccharidic composition could be an anatomical adaptation to marked forces specifically applied to this tendon. However, the ultrasound and histological appearances are very similar to those described in tendinosis, which represents a confounding factor in diagnosing tendonitis at the insertion of the supraspinatus. In the absence of other ultrasonographic criteria of tendinopathy, a hypoechoic central area in the ST near its insertion should be considered normal.

Download Full-text

Feline shoulder arthroscopy using a caudolateral portal, a cadaveric study

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-08-10-0100 ◽

2009 ◽

Vol 22 (04) ◽

pp. 289-293 ◽

Cited By ~ 2

Author(s):

P. Ridge

Keyword(s):

Biceps Brachii ◽

Shoulder Arthroscopy ◽

Gross Anatomy ◽

Cadaveric Study ◽

Banded Structure ◽

Glenohumeral Ligament ◽

Subscapularis Muscle ◽

Iatrogenic Trauma ◽

Biceps Brachii Tendon

SummaryThe aim of this cadaveric study was to determine the normal arthroscopic anatomy of the feline shoulder from a caudolateral arthroscope portal, to compare this with the gross anatomy evident upon dissection, and to determine the degree of iatrogenic trauma caused by the arthroscopy. A 1.9 mm, 30° fore oblique arthroscope via a caudolateral portal, and a 21-gauge needle via a cranio-lateral egress portal were used to assess intra-articular structures in eight feline cadaveric shoulders. The medial glenohumeral ligament was shown to be a single banded structure in the craniomedial compartment, and the subscapularis muscle tendon of insertion was visible in all eight shoulders. The biceps brachii tendon and sheath could be examined, although the transverse humeral ligament was not evident arthroscopically from this portal. The lateral glenohumeral ligament was not demonstrated arthroscopically, although a well-defined capsular thickening was present on dissection. No significant neurovascular trauma was evident after arthroscopy.

Download Full-text

The Role of Deadlifts in Distal Biceps Brachii Tendon Ruptures: An Alternative Mechanism Described With YouTube Videos

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121991811 ◽

2021 ◽

Vol 9 (3) ◽

pp. 232596712199181

Author(s):

Mehmet Kapicioglu ◽

Emre Bilgin ◽

Necip Guven ◽

Anil Pulatkan ◽

Kerem Bilsel

Keyword(s):

Tendon Rupture ◽

Biceps Brachii ◽

Biceps Tendon ◽

Alternative Mechanism ◽

Distal Biceps Tendon ◽

Distal Biceps ◽

Biceps Tendon Rupture ◽

Significant Difference ◽

Biceps Brachii Tendon ◽

Youtube Videos

Background: The classic injury mechanism of a distal biceps brachii tendon rupture (DBBTR) is eccentric loading to the flexed elbow when the forearm is supinated. Purpose: To determine alternative mechanisms of a DBBTR in powerlifting sports, particularly in deadlift competitions, with the use of YouTube videos. Study Design: Descriptive epidemiology study. Methods: A search on YouTube was performed using the search terms “distal biceps tendon rupture” and “distal biceps tendon injury” combined with “competition,” “deadlift,” and “powerlifting.” The videos underwent an evaluation for accuracy by 3 surgeons according to predetermined criteria. Type of sports activity, participant sex, side of the injury, and arm positions at the time of the injury were recorded. Results: Among the videos reviewed, 35 injuries were found appropriate for an evaluation. All participants were male. The majority of the injuries (n = 25) were observed during the deadlift. Only in 1 deadlift injury were both forearms in supination. In the remaining deadlift injuries (n = 24), all elbows were in extension, with 1 forearm in supination and the other in pronation. Among the deadlift injuries in the mixed-grip position, all ruptures occurred in a supinated extremity: 25% (n = 6) of ruptures occurred on the right side, and 75% (n = 18) of ruptures occurred on the left side; this was a significant difference ( P = .014). Conclusion: We described an alternative mechanism for a DBBTR, namely, eccentric loading to an extended elbow when the forearm is supinated during the deadlift. As all the ruptures occurred in a supinated extremity, holding the bar with both forearms in pronation may prevent or decrease the risk of ruptures during the deadlift.

Download Full-text