Management of irreparable subscapularis tendon tears

Habilitationsschrift

zur Erlangung der Lehrbefähigung
für das Fach


Orthopädie

vorgelegt der Medizinischen Fakultät der Charité - Universitätsmedizin Berlin

von

Dr. med. Ariane Gerber Popp


geboren am 7. Juli 1965 in Porrentruy, Schweiz

Dekane:
Prof. Dr. med. J. W. Dudenhausen
Prof. Dr. med. M. Paul

Eingereicht: April/ 2004

Öffentlich-wissenschaftlicher Vortrag: 21.11.2004

Gutachter:
1. Prof. Dr. med. A. Imhoff, München
2. Prof. Dr. med. P. Hoffmeyer, Genf

I grew up with an ambition and determination without which I would have been a good deal happier. I thought a lot and developed the far-away look of a dreamer, for it was always the distant heights which fascinated me and drew me to them in spirit. I was not sure what could be accomplished by means of tenacity and little else, but the target was set high and each rebuff only saw me more determined to see at least one major dream through to its fulfillment.

Earl Denman, Alone to Everest

Table of contents

• 1 INTRODUCTION
  • 1.1 Irreparable rotator cuff tears: definitions and therapeutical principles
    • 1.1.1 Fatty degeneration and atrophy of the rotator cuff muscles
    • 1.1.2 Patterns of chronic rotator cuff tears
    • 1.1.3 Surgical approaches to irreparable rotator cuff lesions
  • 1.2 Structural fundamentals of skeletal muscle
    • 1.2.1 Structural models
    • 1.2.2 Contractile mechanism
    • 1.2.3 Relevance of muscle capabilities in tendon transfer surgery
  • 1.3 Tendon transfer procedures around the shoulder
    • 1.3.1 Overview on clinical experience
      • 1.3.1.1 Tendon transfer procedures for irreparable subscapularis and anterosuperior tears
  • 1.4 Scientific objectives of the monograph
  • 1.5 References
• 2 ANATOMY
  • 2.1 The subscapular nerves are anatomical constraints to circumferential release of the subscapularis muscle
    • 2.1.1 Introduction
    • 2.1.2 Material and Methods
    • 2.1.3 Results
    • 2.1.4 Discussion
    • 2.1.5 References
  • 2.2 Selective reconstruction of the lower subscapularis with the teres major. Anatomical basis for a new tendon transfer
    • 2.2.1 Introduction
    • 2.2.2 Material and Methods
    • 2.2.3 Results
      • 2.2.3.1 Vascular supply
      • 2.2.3.2 Neural supply
      • 2.2.3.3 Description of the latissimus dorsi and teres major tendons
      • 2.2.3.4 Transfer of the teres major to the lesser tuberosity
    • 2.2.4 Discussion
    • 2.2.5 References
• 3 BIOMECHANICS
  • 3.1 Three-dimensional anatomy of the rotator cuff
    • 3.1.1 Introduction
    • 3.1.2 Material and Methods
      • 3.1.2.1 Specimen preparation
      • 3.1.2.2  Data collection
      • 3.1.2.3 Computer modelling and calculation
    • 3.1.3 Results
    • 3.1.4 Discussion
    • 3.1.5 References
  • 3.2 Tendon transfer procedures for irreparable subscapularis tears. A three-dimensional vector analysis
    • 3.2.1 Introduction
    • 3.2.2 Material and Methods
      • 3.2.2.1 Specimen preparation
      • 3.2.2.2 Data collection, modelling and calculation
    • 3.2.3 Results
      • 3.2.3.1 Pectoralis major transfer according to Wirth and Rockwood (PM-I)
      • 3.2.3.2 Pectoralis major transfer by Warner (PM-II)
      • 3.2.3.3 Pectoralis major transfer by Resch (PM-III)
      • 3.2.3.4 Combined teres major-split pectoralis major transfer (TM-sPM transfer)
    • 3.2.4 Discussion
    • 3.2.5 References
• 4 CLINICAL APPLICATIONS
  • 4.1 The combined teres major and spilt pectoralis major transfer for selective reconstruction of irreparable subscapularis tears
    • 4.1.1 Introduction
    • 4.1.2 Material and Methods
      • 4.1.2.1 Concept of selective subscapularis reconstruction (Fig.1)
      • 4.1.2.2 Patients
      • 4.1.2.3 Structural lesions, indication for transfer surgery (Table II)
      • 4.1.2.4 Surgical technique
      • 4.1.2.5 Evaluation
    • 4.1.3 Results
      • 4.1.3.1 Clinical outcome (Table III)
      • 4.1.3.2 Radiographic outcome
      • 4.1.3.3 Complications
    • 4.1.4 Discussion
    • 4.1.5 References
• 5 CONCLUSIONS
• EIDESSTATTLICHE VERSICHERUNG
• REFERENCES
• ACKNOWLEDGEMENTS

Tables

• TABLE I: Overview of the mean horizontal and vertical distances between the lateral border of the coracoid and the entry point of the subscapularis nerve branches into the suscapularis muscle
• TABLE I: Vector orientation with the arm in position 1
• TABLE II: Vector orientation with the arm in position 2
• TABLE III: Vector orientation with the arm in position 3
• TABLE IV: Vector orientation with the arm in position 4
• TABLE I : Comparision of the subscapularis vector and PM-I transfer vector
• TABLE II : Comparision of the subscapularis vector and the PM–II transfer vector
• TABLE III: Comparision of the subscapularis vector and the PM-III vector
• TABLE IV : Comparision of the subscapualris vectors and the TM-PM transfer vectors
• TABLE I : Demographic data and history of first seven patients treated with a combined TM-sPM transfer
• TABLE II : Structural lesions
• TABLE III: Relevant preoperative and postoperative clinical data

Images

• Figure 1: The tension-length curve
• Figure 2a: Distribution of the nerve entry points before release of the subscapularis with the arm in neutral rotation. Red points: upper subscapular nerve branches; green points middle subscapular nerve branches; blue points lower subscapular nerve branches. Star:base of the coracoid process.
• Figure 2b: Distribution of the nerve entry points after release of the subscapularis and lateral traction on the tendon. Red points: upper subscapular nerve branches; green points middle subscapular nerve branches; blue points lower subscapular nerve branches. Star:base of the coracoid process.
• Figure 1: Anterior view of a right shoulder showing the neurovascular pedicle(1) to the teres major(*). The main artery is emerging from the thoracodorsal artery(2) and the innervation comes from the lower subscapular nerve(4). The latissimus dorsi tendon(5) has been detached from the humerus. Thoracodorsal nerve(3).
• Figure 2: Type II pattern where the superior edge of the latissimus dorsi tendon(1) inserts at the same level as the superior edge of the teres major(2), whereas the lower edge inserts more cranially. The lower picture shows the complete teres major insertion(2) after detachment of the latissimus dorsi tendon(1).
• Figure 3: Note the proximity of the radial nerve(1) to the lower border of the teres major tendon(3), when the latissimus dorsi is retracted medially(2). Subscapularis(4), axillary nerve and circumflex vessels(5).
• Fig 1a: Experimental set-up showing positionning of the specimen and the arm before data collection
• Fig1b: Superior view of th especimen. Plexiglas cubes were used to create multiple coordinate systems.
• Fig 1c: The scapula was rigidly fixed to the thorax with an external fixator.
• Figure 2: A Microscribe 3D-X digitizer (Immersion Corp., San Jose, CA) was used to register the three-dimensional anatomy of the joint and the above described muscles. The device was fixed rigidly to the custom built jig which was used to stabilize the specimens.
• Figure 3a. Example of a model. Left shoulder from the anterior view. Humeral head(1), humeral shaft(2), clavicular head of the pectoralis major(3), sternal head of the pectoralis major(4), teres major(5).
• Figure 3a. Superior view. Humeral head(1), glenoid(2), clavicular head of the pectoralis major(3), sternal head of the pectoralis major(4), teres major(5).
• Figure 4: Definition of the reference system to calculate the angles α and β
• Figure 1: Two planes of reference were used to defined the vector orientation.
• Figure 3: Anterior view of a right shoulder after PM-II tansfer. The sternal head (1) has been rerouted underneath the clavicular head and attached to the greater tuberosity.
• Figure 4: Anterior view of a right shoulder after TM-PM tansfer. The teres major(1) has been transferred to the lower part of the lesser tuberosity, whereas the sternal head of the pectoralis major(2) has been rerouted underneath its clavicular head(3) and attached to the superior part of the lesser tuberosity. Conjoined tendon (4)
• Figure 1: Schematic representation of the transfer illustrating the principle of selective reconstruction of the subscapularis muscle. The teres major muscle is transferred to the lower lesser tuberosity whereas the sternal part of the pectoralis major is rerouted underneath its clavicular head and fixed to the upper tuberosity.
• Figure 2: The pectoralis major tendon is identified at its humeral insertion. The tendon of the sternal head, which inserts to the humerus underneath the clavicular head, is carefully dissected and sharply released from the bone humerus. Number 2, braided, nonabsorbable sutures are placed through the end of the pectoralis tendon using modified Mason-Allen stiches. The sternal head of the pectoralis major muscle is dissected medially so that it can be oriented laterally and cranially. Medial dissection should not exceed 10 cm to avoid denervation of the sternal head¹¹.
• Figure 3: After dissection the sternal head is rerouted underneath the clavicular portion of the muscle.
• Figure 4: With the arm in maximal external rotation, the tendon of the latissimus dorsi ist exposed. The upper and the lower border are dissected before the tendon is released from the humerus.To allow refixation of the latissimus tendon at the end of the procedure, a 1 cm large cuff of tendon is left at the humeral shaft. The release tendon is reflected medially after 3 pairs of number 2 braided non-absorbable sutures have been placed in the tendon.
• Figure 5: The plane between the latissimus dorsi and the teres major tendons is well defined laterally, closed to their humeral insertion. Medially the plane becomes less clear and dissection must be meticulous to avoid any damage to the short tendon of the teres major muscle. After exposure of the upper and lower border of the teres major muscle, the tendon is elevated subperiosteally from the humeral shaft and three sets of number 2 braided non-absorbable sutures are placed through the tendon in a modified Mason-Allen configuration.
• Figure 6: The teres major tendon is then mobilized by releasing adhesions to the latissimus dorsi. Dissection at the upper border of the teres major should be performed carefully to avoid any damage to the axillary nerve and the posterior circumflex vessels. Furthermore medial dissection between latissimus dorsi and teres major should not exceed 5 cm from the humeral end of the teres major tendon to save the main pedicle of the transfer. Usually adhesions limiting cranial mobilisation are found between the lower edge of the teres major and the latissimus dorsi and must be released. Before doing so, the surgeon should be aware of the exact location of the radial nerve and the deep brachial artery. Finally the tendon is transferred to the lower portion of the lesser tuberosity. The latissimus is repaired to the humeral shaft.
• Figure 7: The lesser tuberosity and the bicipital groove are decorticated. Both transferred tendons are fixed to the lesser tuberosity using transosseous sutures. The teres major is fixed first to the lower part of the lesser tuberosity. As a rule the transfer should already be tight in neutral rotation, but still allowing 20°-30° of passive external rotation.Then the sternal head of the pectoralis major is fixed to the upper part of the lesser tuberosity with the arm held in 30° of external rotation. The rotator interval between the leading edges of the supraspinatus and the split pectoralis major transfer is closed.
• Figure 8: Intraoperative view of a right shoulder after completion of the combined teres major and split major transfer. Teres major(1), sternal part of the pectoralis major(2), supraspinatus tendon(3), deltoideus(4), conjoined tendon(5), clavicular part of the pectoralis major(6).
• Figure 9a: Clinical outcome (18 months postoperatively) of 65 years old women treated for irreparable anterosuperior tear after total shoulder arthroplasty with total shoulder revision and TM-sPM transfer. Before surgery she had a painful pseudoparalysis of the right arm.
• Figure 9 b: The preoperative axillary view of the shoulder of patient of Figure 9a shows a clear anterior subluxation of the prosthetic head (upper picture). After revision of the prosthesis and TM-sPM transfer the shoulder is centered (lower picture).