The longitudinal anatomy of the long head of the biceps tendon and implications on tenodesis

The morphometric parameters of the biceps brachii: cadaveric study

BACKGROUND

The biceps brachii (BB) is a fusiform muscle comprising of two muscular bellies located in the anterior compartment of the arm. Its primary function includes elbow flexion and forearm supination.

PURPOSE

The study aimed to examine the morphometric parameters of the BB in adult cadaveric specimens.

METHODS

This dissection-based study examined the anatomy of the BB in 40 arms taken from 20 Thiel embalmed European cadavers, including 13 males with an average age of 81 years and seven females with an average age of 84 years. The investigation included an observational inspection of the BB morphology and collected 19 parameters, comprising the lengths and widths of the short and long head tendons and muscle bellies.

RESULTS

The observation analysis showed that the anatomy of the BB consisted mainly of two muscle bellies: a short head and a long head. An additional third humeral head, originating from the anteromedial aspect of the mid of the humerus and inserted into the common biceps tendon, was observed in four (10%) specimens. The average lengths of the short head and long head were 35.98 ± 3.44 cm and 38.90 ± 3.40 cm, respectively. There was no difference in the BB parameters according to the arm sides. However, the male specimens showed greater BB parameters than the female specimens.

CONCLUSION

The short head had a greater muscle belly, while the long head had a longer origin and insertion tendons. The BB parameters were correlated positively with the humerus length.

Arthroscopic Evaluation of the Long Head of the Biceps Tendon: Traditional Versus Allis Clamp Techniques

Using a probe to retract the long head of the biceps tendon (LHBT) into the joint is common practice for visualizing the extra-articular portions during arthroscopy. However, extra-articular lesions may be missed in up to half of cases. Greater excursion of the LHBT may be achieved with an Allis clamp grasper. Our goal was to quantify portions of the extra-articular LHBT that could be visualized during shoulder arthroscopy with the Allis clamp and probe techniques. Shoulder arthroscopy was performed on 8 forequarter cadaveric specimens in the simulated beach chair position, and the most distal extent of the intra-articular LHBT was marked. The tendon was pulled into the joint with both techniques, and the additional exposed tendon portion was marked. An open approach was performed, and the locations of the 3 marks were assessed relative to total tendon length. Mean LHBT total length was 96.25 mm. Diagnostic arthroscopy allowed visualization of a mean of 21.75 mm of the intra-articular tendon (22.6% of the total length). The traditional probe technique provided visualization of 31.13 mm (32.8%). The Allis clamp technique provided visualization of 49.38 mm (52%) and increased visualization of the LHBT by 58.6% (P<.0001). A mean of 46.87 mm (48%) of the LHBT remained unvisualized. The Allis clamp technique maximizes arthroscopic visualization of extra-articular LHBT. The distal 48% eludes evaluation, but can be visualized when combined with an open technique without the need to divide the transverse humeral ligament. The Allis clamp technique facilitates additional identification of LHBT pathology that could otherwise remain hidden during shoulder arthroscopy. Because the LHBT is a major source of pain in the shoulder, this technique may improve outcomes of shoulder arthroscopy and reduce the need for revision because of remnant anterior shoulder pain. [Orthopedics. 2022;45(1):38-42.].

Superior Capsular Reconstruction using the Long Head of the Biceps Tendon: The Biceps Loop Technique

Irreparable rotator cuff tears can be treated in several ways. Superior capsular reconstruction has been reported as an excellent option, particularly for the young and active patients. We propose capsule reconstruction using the long head of the biceps tendon in a modified way. After its tenotomy at the musculotendinous junction, the long head is rerouted through a humeral bone tunnel and attached to a suture anchor in the posterior aspect of the superior glenoid rim. Further investigation is required, but this modified technique appears promising.

Characterization of the Proximal Long Head of Biceps Tendon Anatomy Using Magnetic Resonance Imaging: Implications for Biceps Tenodesis

BACKGROUND

Biceps tenodesis is a common treatment for proximal long head of biceps (LHB) tendon pathology. To maintain biceps strength and contour and minimize cramping, restoration of muscle-length tension and appropriate positioning of the tenodesis is key. Little is known about the biceps musculotendinous junction (MTJ) anatomy, especially in relation to the overlying pectoralis major tendon (PMT), which is a commonly used landmark for tenodesis positioning.

PURPOSE

To characterize the in vivo topographic anatomy of the LHB tendon, in particular the MTJ relative to the PMT, using a novel axial proton-density magnetic resonance imaging (MRI) sequence.

STUDY DESIGN

Descriptive laboratory study.

METHODS

In total, 45 patients having a shoulder MRI for symptoms unrelated to their biceps tendon or rotator cuff were prospectively recruited. There were 33 men and 12 women, with a mean age of 37 ± 13 years (range, 18-59 years). All patients underwent routine shoulder MRI scans with an additional axial proton density sequence examining the LHB tendon and its MTJ. Three independent observers reviewed each MRI scan, and measurements were obtained for (1) MTJ length, (2) the distance between the proximal MTJ and the superior border of the PMT (MTJ-S), (3) the distance between the distal MTJ to the inferior border of the PMT, and (4) the width of the PMT.

RESULTS

The average position of the MTJ-S was 5.9 ± 10.8 mm distal to the superior border of the PMT. The mean MTJ length was 32.5 ± 8.3 mm and the width of the PMT was 28.0 ± 7.3 mm. We found no significant correlation between patient age, height, sex, or body mass index and any of the biceps measurements. We observed wide variability of the MTJ-S position and identified 3 distinct types of biceps MTJ: type 1, MTJ-S above the PMT; type 2, MTJ-S between 0 and 10 mm below the superior border of the PMT; and type 3, MTJ-S >10 mm distal to the superior PMT.

CONCLUSION

In this study, the in vivo anatomy of the LHB tendon is characterized relative to the PMT using a novel MRI sequence. The results demonstrate wide variability in the position of the MTJ relative to the PMT, which can be classified into 3 distinct subtypes or zones relative to the superior border of the PMT. Understanding this potentially allows for accurate and anatomic placement of the biceps tendon for tenodesis.

CLINICAL RELEVANCE

To our knowledge, this is the first study to radiologically analyze the in vivo topographic anatomy of the LHB tendon and its MTJ. The results of this study provide more detailed understanding of the variability of the biceps MTJ, thus allowing for more accurate placement of the biceps tendon during tenodesis.

Clinical relevance of the anatomy of the long head bicipital groove, an evidence-based review

Pathology in the bicipital groove can be a source of anterior shoulder pain. Many studies have compared treatment techniques for the long head biceps tendon (LHBT) without showing any clinically significant differences. As the LHBT is closely related to the bicipital groove, anatomical aspects of this groove could also be implicated in surgical outcomes. The aim of this review is to contribute to developing the optimal surgical treatment of LHBT pathology based on clinically relevant aspects of the bicipital groove. Medline/PubMed was systematically searched using key words "bicipital" and "groove" and combinations of their synonyms. Studies reporting on evolution, embryonic development, morphometry, vascularization, innervation, and surgical treatment of the LHBT and the bicipital groove were included. The length of the bicipital groove reported in the included studies ranged from 81.00 mm to 87.33 mm, width from 7.74 mm to 11.60 mm, and depth from 3.70 mm to 6.00 mm. The anatomy of the bicipital groove shows a bottleneck narrowing approximately two-thirds from superior. The transverse humeral ligament can constrain the bicipital groove and could be involved in anterior shoulder pain. When either LHBT tenotomy or tenodesis is performed, routinely releasing the transverse ligament could decrease postoperative anterior shoulder pain, which has frequently been reported in the literature. To avoid the bottle neck narrowing, a location below the bicipital groove may be preferred for biceps tenodesis over a more proximal tenodesis site. Level of evidence: IV.

Surgical anatomy of the pectoralis major tendon insertion revisited: relationship to nearby structures and the pectoral eminence for defining the anatomic footprint

Background

Intraoperative identification of the normal pectoralis major (PM) footprint can be challenging to identify in the acute and chronic settings. The purpose of this study was to revisit the anatomic footprint of the PM tendon and to determine which nearby landmarks can be used to re-create the normal insertion site during anatomic repair or reconstruction.

Methods

Twenty-one fresh-frozen human cadaveric shoulder specimens were used to define the PM tendon width (ie, superior-to-inferior) and to determine the relationship between the superior aspect of the PM insertion and that of the latissimus dorsi (LD) and anterior deltoid (AD) tendons. An attempt was made to identify potential useful bony landmarks that can be used during anatomic repair or reconstruction of the PM tendon.

Results

The mean PM tendon width was 68.8 ± 4.4 mm. The superior margin of the LD insertion was 9.4 ± 5.9 mm above and the AD was 48.4 ± 7.1 mm below the superior margin of the PM tendon insertion, respectively. In 17 of 21 specimens (81%), the superior insertion of the PM tendon attached onto a bony prominence, named the pectoral eminence.

Conclusions

The LD and AD tendon insertions represent reliable soft tissue landmarks for identifying the superior extent of the PM tendon along its bony footprint. The pectoral eminence can also be used as an additional reference point in the majority of cases to facilitate anatomic restoration of the pectoralis tendon during repair and reconstruction. Surgeons should be familiar with the proximity of nearby neurovascular structures when performing PM repairs.

Biceps tenodesis versus biceps tenotomy for biceps tendinitis without rotator cuff tears

Disorders of the long head of the biceps tendon (LHB) are a well-recognised cause of shoulder pain despite the function of the long head of the biceps remaining poorly understood. There has been a dramatic rise in the number of biceps tenodesis procedures being performed in the last decade. This may partly be attributed to concerns regarding residual cosmetic deformity and pain after biceps tenotomy though there is little evidence to suggest that functional outcomes of tenodesis are superior to biceps tenotomy. Current literature focuses on LHB disorders with concomitant rotator cuff tears. The aim of this review is to discuss the anatomy of the LHB, the pathogenesis of tendinopathy of the LHB, indications of biceps tenodesis and tenotomy and compare the current literature on the functional outcomes of these procedures for LHB disorders in the absence of rotator cuff tears.

The modified Norwegian method of biceps tenodesis: how well does it work?

PURPOSE

The purpose of this study was to evaluate clinical outcomes and complications in a series of patients who underwent the modified Norwegian method (MNM) of biceps tenodesis by a single shoulder surgeon.

METHODS

A retrospective review of charts from all patients who underwent the modified Norwegian method of biceps tenodesis by the senior author during a 5-year period between 2008 and 2013 was performed. After all patients were identified, informed consent was obtained and DASH and ASES surveys were administered. Inclusion criteria for the study were a minimum 2-year follow-up after MNM tenodesis and appropriate adherence to DASH and ASES survey protocol. Data obtained included: demographic data, time to follow-up, hand dominance, concomitant procedures, workman's compensation (WC) status, DASH and ASES surveys, and complications. A complication was defined as rupture of the tenodesis or post-operative infection. Residual shoulder pain was considered as treatment failure. The data were then analysed using statistical software. In this time period, 94 biceps tenodeses using the MNM technique were performed. Follow-up rate was 75/94 patients (80 %). Of 75 patients, 15 (20 %) had an isolated tenodesis performed.

RESULTS

There was no statistically significant difference in DASH or ASES scores when comparing isolated tenodesis patients to those who had concomitant procedures. WC patients had worse DASH and ASES scores (p = 0.016; p = 0.002). The complication rate was 2/75 (3 %), which were both ruptured tenodeses. Of 75 patients, 3 (4 %) experienced treatment failure with residual anterior shoulder pain.

CONCLUSIONS

There is debate in the literature regarding the optimal method of biceps tenodesis. This paper demonstrates that the MNM tenodesis appears to be a simple, efficient, and effective alternative to other methods of biceps tenodesis with subjective outcome scores and complication rates that parallel other methods previously described in the literature.

LEVEL OF EVIDENCE

IV.

Biceps Tenodesis: Anatomic Tensioning

Biceps tenodesis is a commonly employed surgical intervention for refractory symptoms related to the biceps-labral complex, those intra-articular and those within the extra-articular bicipital tunnel. While a litany of surgical techniques exists, the optimal method for ensuring an anatomic length-tension relationship during tenodesis remains elusive. Appropriate tensioning may limit undesirable outcomes such as cramping or cosmetic deformity. We describe herein our technique as a simple and efficient means to establish patient-specific, anatomic tensioning of the long head of the biceps during tenodesis.

Qualitative Assessment and Quantitative Analysis of the Long Head of the Biceps Tendon in Relation to the Pectoralis Major Tendon Humeral Insertion: An Anatomic Study

PURPOSE

To qualitatively assess and to quantitatively analyze the long head of the biceps tendon (LHBT) in the region of the pectoralis major (PM).

METHODS

From 11 fresh cadaveric donors, 20 cadaveric shoulders without operative scars were dissected-mean age, 76.9 years (range, 61 to 93 years); male, 75%; left-sided, 55%; mean height, 67.8 inches (range, 61 to 71 inches); mean weight, 148.1 pounds (range, 106 to 176 pounds). Two specimens with discovered ruptures were excluded. The LHBT circumference was measured at the anterior edge of supraspinatus, suprapectorally, midpectorally, and subpectorally. The muscle was then removed from the LHBT and the circumference was again measured at the supra-, mid-, and subpectoral levels. These data were used to calculate the area of the tendon. All measurements were performed by 2 independent observers. Statistical analysis was performed to assess reliability of data and the difference between serial measurements.

RESULTS

The mean calculated percentage tendon decreased from 86.7% at the superior edge of the PM to 49.8% at the midpoint of the PM and to 17.5% at the inferior edge of the PM.

CONCLUSIONS

Distal to the PM, the LHBT was composed of a small percentage of tendon to muscle, which may have implications for the mechanical strength of fixation of tenodesis. The anatomic location of the musculotendinous junction of the LHBT began proximal to the superior edge of the PM tendon, which implies that restoration of anatomic tensioning may require a more proximal docking site than previously described. Tenodesis performed between the midpoint of the PM insertion and more distal points involves a significant portion of muscle, which may not be optimal.

CLINICAL RELEVANCE

Tenodesis performed between the midpoint of the PM insertion and more distal points involves a significant portion of muscle, which may affect the mechanical strength or optimal choice of fixation location.

All-Arthroscopic Suprapectoral Biceps Tenodesis

Biceps tenodesis is a common treatment for pathology of the long head of the biceps tendon. Several authors have described various arthroscopic and open techniques for biceps tenodesis. Open techniques have been associated with complications such as wound infection and nerve injury. Previously described arthroscopic techniques have placed the tenodesis site within the bicipital groove, which may lead to persistent pain. We describe an all-arthroscopic suprapectoral biceps tenodesis technique that places the tenodesis site distal to the bicipital groove. This technique potentially avoids the complications associated with open tenodesis surgery while still removing the biceps tendon from the bicipital groove.

Regional mechanical properties of the long head of the biceps tendon

BACKGROUND

Long head of the biceps tenodesis reliably relieves pain, and restores strength, stability, and normal appearance of the upper extremity in the event of biceps tendinopathies. Regional differences in tendon mechanics may provide surgeons with valuable guidance in the placement of the tenodesis repair construct. The purpose of this study was to compare the mechanical properties of the long head of the biceps tendon in three functional regions of the tendon: intra-articular (proximal), suprapectoral (middle), and subpectoral (distal).

METHODS

Uniaxial tensile tests were performed on the long head of the biceps tendon segments to quantify the material and structural properties of the tendon. Material properties were obtained using dogbone-shaped specimens while structural properties were obtained using intact specimens where the clamp boundary conditions simulated the common "gold standard" tenodesis, the interference screw.

FINDINGS

Elastic modulus for the supra- and subpectoral regions were significantly greater than the intra-articular region (P≤0.048). The tensile strength of the subpectoral region tended to be lower compared to all other functional regions (P=0.051). The failure mechanism for intact specimens was similar to that seen for interference screw fixation where tissue failure occurs due to tearing at the bone/tendon/screw interface.

INTERPRETATION

The higher tensile strength of the suprapectoral region compared to the subpectoral region may make this a more desirable location for tenodesis placement based on tissue strength. Similar elastic moduli and structural stiffness between the supra- and subpectoral regions indicate that the construct type may play a bigger role in functional outcomes in relation to construct deformation.