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Measurement of the tendon of the biceps brachii after tenotomy: study on cadavers 2 ☆ Work performed within the Shoulder and Elbow Group, Orthopedics and Traumatology Service, Hospital do Servidor Público Estadual, São Paulo, SP, Brazil.

ABSTRACT

OBJECTIVE:

To evaluate the influence of elbow and forearm range of motion on the distal excursion of the long head of the biceps (LHB). METHODS: The distal excursion of the LHB after tenotomy of the shoulders of eight cadavers was ascertained by measuring the distance between a point marked out on the LHB, 3 cm from the anterolateral border of the acromion, and its position at different degrees of elbow flexion, using a digital pachymeter. The measurements at elbow flexion of 135°, 90°, 45° and 0° were noted: these angles were established using a goniometer. The measurements were made with the forearm in neutral, supination and pronation positions. RESULTS: Differences between the mean measurements of the distal excursion of the LHB (total sample) were observed between the degrees of elbow flexion ( p< 0.01). However, no statistical differences were observed between the different forearm positions, between the sides, genders and ages of the cadavers studied. CONCLUSION: Progressive extension of the elbow caused progressive distal excursion of the LHB, but without interference in the forearm position, gender, side or age of the cadavers studied.

Keywords:
Shoulder joint; Glenoid cavity; Tenotomy

RESUMO

OBJETIVO:

Avaliar a influência da amplitude de movimento do cotovelo e do antebraço na excursão distal da cabeça longa do bíceps (CLB). MÉTODOS: Verificou-se a excursão distal da cabeça longa do bíceps (CLB) após tenotomia em ombros de oito cadáveres, por meio da aferição da distância entre um ponto demarcado na cabeça longa do bíceps (CLB) a 3 cm da borda anterolateral do acrômio em flexão máxima e sua posição em diferentes graus de flexão do cotovelo, com o uso de um paquímetro digital. Foram anotadas as medidas nos graus de flexão do cotovelo 135°, 90°, 45° e 0°, estabelecidas com o uso de um goniômetro. As medidas foram tomadas com o antebraço em posição neutra, supinação e pronação. RESULTADOS: Observou-se diferença entre as médias das medidas da excursão distal da cabeça longa do bíceps (CLB) (amostra total) entre os graus de flexão do cotovelo (p < 0,01). Todavia, não foi encontrada diferença estatística entre diferentes posições do antebraço, entre os lados, gêneros e idades dos cadáveres estudados. CONCLUSÃO: A extensão progressiva do cotovelo ocasionou a excursão distal progressiva da cabeça longa do bíceps (CLB), mas sem interferência da posição do antebraço, gênero, lado e idade dos cadáveres estudados.

Palavras-chave:
Articulação do ombro; Cavidade glenoide; Tenotomia

Introduction

The long head of the tendon of the biceps brachii muscle (LHB) is developed at around the seventh to eighth week of gestation and it becomes differentiated starting from the mesoderm. It is described as continuous with the labrum of the glenoid and the supraglenoid tubercle, and it passes anteriorly and superiorly to the head of the humerus before entering the bicipital groove. 1. Gardner E, Gray DJ. Prenatal development of the human shoulder and acromioclavicular joints. Am J Anat. 1953;92(2):219-76. and 2. Jobe C. Gross anatomy of the shoulder. In: Rockwood C, editor. The shoulder. Philadelphia: Elsevier; 2009.It is intra-articular and extrasynovial and slides passively over the head of humerus during abduction or rotation. Its length is 9 cm and its diameter is 5-6 mm. It innervation is through a network of sensory fibers of the sympathetic nervous system. 3. Hitchcock HH, Bechtol CO. Painful shoulder: observations on the role of the tendon of the long head of the biceps brachii in its causation. J Bone Joint Surg Am. 1948;30(2):263-73. 4. Alpantaki K, McLaughlin D, Karagogeos D, Hadjipavlou A, Kontakis G. Sympathetic and sensory neural elements in the tendon of the long head of the biceps. J Bone Joint Surg Am. 2005;87(7):1580-3. and 5. Bey MJ, Elders GJ, Huston LJ, Kuhn JE, Blasier RB, Soslowsky LJ. The mechanism of creation of superior labrum, anterior, and posterior lesions in a dynamic biomechanical model of the shoulder: the role of inferior subluxation. J Shoulder Elbow Surg. 1998;7(4):397-401.

The biceps extends from the scapula to the forearm and has functions relating to the shoulder and elbow. Its function relating to the elbow has been well established and includes both flexion and supination. On the other hand, in relation to the shoulder, although several functions have been attributed, the exact role of the LHB remains a matter of controversy. 6. Sethi N, Wright R, Yamaguchi K. Disorders of the long head of the biceps tendon. J Shoulder Elbow Surg. 1999;8(6):644-54.Electromyographic analyses have shown that the LHB serves as a stabilizer in unstable joints, but not in stable shoulders. 7. Kim SH, Ha KI, Kim HS, Kim SW. Electromyographic activity of the biceps brachii muscle in shoulders with anterior instability. Arthroscopy. 2001;17(8):864-8.Biomechanical studies have demonstrated that the tendon acts as a dynamic depressor of the head of the humerus, but this has not been proven clinically. 8. Kumar VP, Satku K, Balasubramaniam P. The role of the long head of biceps brachii in the stabilization of the head of the humerus. Clin Orthop Relat Res. 1989;244:172-5. and 9. Warner JJ, McMahon PJ. The role of the long head of the biceps brachii in superior stability of the glenohumeral joint. J Bone Joint Surg Am. 1995;77(3):366-72.Kuhn et al. 1010 . Kuhn JE, Huston LJ, Soslowsky LJ, Shyr Y, Blasier RB. External rotation of the glenohumeral joint: ligament restraints and muscle effects in the neutral and abducted positions. J Shoulder Elbow Surg. 2005;14 1 Suppl S:39S-48S.demonstrated its importance as a restrictor of external rotation of the abducted arm.

Lesions of the superior glenoid that involve the LHB are called SLAP lesions (superior labrum, anterior and posterior). They were first described at the beginning of the 1990s by Snyder et al. 1111 . Snyder SJ, Karzel RP, Del Pizzo W, Ferkel RD, Friedman MJ. SLAP lesions of the shoulder. Arthroscopy. 1990;6(4):274-9.The conservative or surgical treatment for these lesions has been well established, but there has never been a consensus regarding the postoperative rehabilitation treatment. There are protocols described in the current literature, 1212 . Andrews JR, Carson WG, McLeod WD. Glenoid labrum tears related to the long head of the biceps. Am J Sports Med. 1985;13(5):337-41. and 1313 . Wilk KE, Reinold MM, Dugas JR, Arrigo CA, Moser MW, Andrews JR. Current concepts in the recognition and treatment of superior labral (SLAP) lesions. J Orthop Sports Phys Ther. 2005;35(5):273-91.in which early mobility of the extended elbow is avoided because of doubts regarding the consequent tensioning of the proximal LHB and superior glenoid labrum, which were reinserted during the operation. These actions could cause failure of healing and a new injury. 1212 . Andrews JR, Carson WG, McLeod WD. Glenoid labrum tears related to the long head of the biceps. Am J Sports Med. 1985;13(5):337-41. and 1313 . Wilk KE, Reinold MM, Dugas JR, Arrigo CA, Moser MW, Andrews JR. Current concepts in the recognition and treatment of superior labral (SLAP) lesions. J Orthop Sports Phys Ther. 2005;35(5):273-91.

The objective of this study was to evaluate the influence of the range of motion of the elbow and forearm on the distal excursion of the LHB.

Methods

This study was approved by our institution's research ethics committee (number: CAAE 19893114.6.0000.5463). Sixteen shoulders of eight cadavers obtained from the Death Verification Service of the University of São Paulo (SVOC-USP) were dissected. None of these cadavers presented any fractures of the upper limbs, local deformities or scarring. The dissections were performed by means of an anterolateral access measuring 10 cm ( Fig. 1A), followed by dissection between the anterior and lateral deltoid muscle ( Fig. 1B) so as to approach and dissect the LHB ( Fig. 1C).

Fig. 1
Tenotomy procedure on a cadaver. (A) Marking out the bone anatomical parameters and access route; (B) access via anterolateral route; (C) dissection of the LHB from its groove to its origin in the glenoid; (D) measurement of the excursion of the LHB after proximal tenotomy, with elbow flexion at 135°, 90°, 45° and 0°.

Using a surgical pen, a line perpendicular to the LHB was marked out, 3 cm distally to the anterolateral border of the acromion. Tenotomy of the LHB was performed at its origin in the supraglenoid tubercle, with the elbow at maximum flexion. The distal excursion of the LHB was verified by measuring the distance between the line marked out on the bicipital tendon and needles placed at the edge of the line previously established on the LHB, using a digital pachymeter (Lee Tools, Houston, USA) ( Fig. 1D), as the elbow was extended. Measurements were noted at the following degrees of elbow flexion: 135°, 90°, 45° and 0°, which were established using a goniometer. The measurements were made with the forearm in the neutral, supination and pronation positions.

Statistical analysis

To compare the results from the measurements on the distal excursion of the LHB, the Friedman test was used. To determine the measurements between which statistically significant differences occurred, the Wilcoxon test was used. For all the tests, the rejection level for the hypothesis of nullity was 0.05 (significance level of 95%).

The Friedman and Wilcoxon tests were also used to compare the results from the measurements on the excursion of the LHB separately and on the entire sample. To compare the results from the measurements according to sex and side studied, the Mann-Whitney test was used. To evaluate the relationship between age and the results from the measurements made, the Spearman correlation was used.

Results

Among the eight cadavers dissected, five were female and three were male. There were eight right shoulders and eight left shoulders ( Table 1). The mean value for the distal excursion of the LHB with the forearm in the neutral position and at 135° of elbow flexion was 1.41 mm; at 90°, 13.97 mm; at 45°, 18.01 mm; and at 0°, 22.53 mm ( Table 2). When these measurements were made with the forearm moved into pronation and supination positions, there were no differences in relation to the above measurements.

Table. 1
Measurements (in mm, using a digital pachymeter) of the distal excursion at elbow flexions of 135°, 90°, 45° and 0° (angles obtained by means of a goniometer).

Table. 2
Statistical analysis on the measurements of the distal excursion of the LHB in relation to the total sample.

Comparisons between the measurements on the distal excursion of the LHB showed significant differences ( p< 0.001), considering the entire sample, at all degrees of elbow flexion ( Table 2). On the other hand, there were no statistical differences between the right and left sides ( Table 3), between the male and female sexes ( Table 4) or between the ages ( Table 5), among the cadavers studied.

Table. 3
Statistical analysis on the measurements of the distal excursion of the LHB in relation to the sides.

Table. 4
Statistical analysis on the measurements of the distal excursion of the LHB in relation to sex.

Table. 5
Statistical analysis on the measurements of the distal excursion of the LHB in relation to age.

Discussion

This study is in agreement with the study conducted by Gramstad et al., 1414 . Gramstad GG, Sears BW, Marra G. Variation of tension in the long head of the biceps tendon as a function of limb position with simulated biceps contraction. Int J Shoulder Surg. 2010;4(1):8-14.with evidence of increasing distal excursion of the LHB as the elbow is extended. On the other hand, according to those authors, not only elbow extension but also pronation of the forearm was associated with increased tension on the LHB, and on the superior labrum of the glenoid. In our observations, no differences in distal excursion of the LHB were seen with regard to the positioning of the forearm (pronation or supination). This difference in results can possibly be explained by the fact that those authors made their measurements with the shoulder abducted at 60°, whereas in our study, the measurements were made with the shoulder adducted against the body.

According to Wilk et al., 1313 . Wilk KE, Reinold MM, Dugas JR, Arrigo CA, Moser MW, Andrews JR. Current concepts in the recognition and treatment of superior labral (SLAP) lesions. J Orthop Sports Phys Ther. 2005;35(5):273-91.in postoperative treatment for SLAP lesions, active and passive elbow extension exercises are indicated starting in the first ten days after the operation, only for patients who underwent simple debridement (types I and III of Snyder's classification). However, among patients who underwent repairs to SLAP lesions (types II and IV of Snyder's classification), early complete extension of the elbow and the consequent proximal bicipital tensioning should be avoided. This guidance is concordant with the findings from our study, since greater distal excursion of the LHB after tenotomy at its origin was demonstrated as the elbow was progressively extended.

Conclusions

After tenotomy at the origin of the LHB, progressive extension of the elbow caused progressive distal excursion of the LHB, but without interference from the position of the forearm or from the sex, side or age of the cadavers studied.

Acknowledgements

The authors thank the orthopedics team at Hospital do Servidor Público Estadual, São Paulo, and the team of the Death Verification Service for their support in carrying out this study.

References

  • 1
    Gardner E, Gray DJ. Prenatal development of the human shoulder and acromioclavicular joints. Am J Anat. 1953;92(2):219-76.
  • 2
    Jobe C. Gross anatomy of the shoulder. In: Rockwood C, editor. The shoulder. Philadelphia: Elsevier; 2009.
  • 3
    Hitchcock HH, Bechtol CO. Painful shoulder: observations on the role of the tendon of the long head of the biceps brachii in its causation. J Bone Joint Surg Am. 1948;30(2):263-73.
  • 4
    Alpantaki K, McLaughlin D, Karagogeos D, Hadjipavlou A, Kontakis G. Sympathetic and sensory neural elements in the tendon of the long head of the biceps. J Bone Joint Surg Am. 2005;87(7):1580-3.
  • 5
    Bey MJ, Elders GJ, Huston LJ, Kuhn JE, Blasier RB, Soslowsky LJ. The mechanism of creation of superior labrum, anterior, and posterior lesions in a dynamic biomechanical model of the shoulder: the role of inferior subluxation. J Shoulder Elbow Surg. 1998;7(4):397-401.
  • 6
    Sethi N, Wright R, Yamaguchi K. Disorders of the long head of the biceps tendon. J Shoulder Elbow Surg. 1999;8(6):644-54.
  • 7
    Kim SH, Ha KI, Kim HS, Kim SW. Electromyographic activity of the biceps brachii muscle in shoulders with anterior instability. Arthroscopy. 2001;17(8):864-8.
  • 8
    Kumar VP, Satku K, Balasubramaniam P. The role of the long head of biceps brachii in the stabilization of the head of the humerus. Clin Orthop Relat Res. 1989;244:172-5.
  • 9
    Warner JJ, McMahon PJ. The role of the long head of the biceps brachii in superior stability of the glenohumeral joint. J Bone Joint Surg Am. 1995;77(3):366-72.
  • 10
    Kuhn JE, Huston LJ, Soslowsky LJ, Shyr Y, Blasier RB. External rotation of the glenohumeral joint: ligament restraints and muscle effects in the neutral and abducted positions. J Shoulder Elbow Surg. 2005;14 1 Suppl S:39S-48S.
  • 11
    Snyder SJ, Karzel RP, Del Pizzo W, Ferkel RD, Friedman MJ. SLAP lesions of the shoulder. Arthroscopy. 1990;6(4):274-9.
  • 12
    Andrews JR, Carson WG, McLeod WD. Glenoid labrum tears related to the long head of the biceps. Am J Sports Med. 1985;13(5):337-41.
  • 13
    Wilk KE, Reinold MM, Dugas JR, Arrigo CA, Moser MW, Andrews JR. Current concepts in the recognition and treatment of superior labral (SLAP) lesions. J Orthop Sports Phys Ther. 2005;35(5):273-91.
  • 14
    Gramstad GG, Sears BW, Marra G. Variation of tension in the long head of the biceps tendon as a function of limb position with simulated biceps contraction. Int J Shoulder Surg. 2010;4(1):8-14.
  • 2
    ☆ Work performed within the Shoulder and Elbow Group, Orthopedics and Traumatology Service, Hospital do Servidor Público Estadual, São Paulo, SP, Brazil.

Publication Dates

  • Publication in this collection
    Aug 2015

History

  • Received
    28 Apr 2014
  • Accepted
    29 July 2014
Sociedade Brasileira de Ortopedia e Traumatologia Al. Lorena, 427 14º andar, 01424-000 São Paulo - SP - Brasil, Tel.: 55 11 2137-5400 - São Paulo - SP - Brazil
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