Pedicle island flaps of latissimus dorsi. Applications in surgical repair of ruptures of the rotator cuff

Anatomic study of pedicled bipolar teres major transfer for irreparable posterosuperior rotator cuff tears

BACKGROUND

Treatment of rotator cuff (RC) tears has not included bipolar muscle-tendon transfers to date. The objective of this study was to verify the feasibility of pedicled bipolar teres major (TM) transfer over and under the long head of the triceps brachii (LHT) and compare its versatility with monopolar transfer in a model of supraspinatus (SS) tears in cadavers.

METHODS

In 6 shoulders of cryopreserved cadavers, we re-created complete SS tears, conducting monopolar and bipolar TM transfers over and under LHT. We compared the morphology of the SS and TM, defect coverage, angle between the transferred TM and major SS axis, and axillary nerve overlap with each technique.

RESULTS

The TM and SS were morphologically similar. Defect coverage was significantly lower with monopolar transfer (12 ± 4 mm) than with bipolar transfer (39 ± 9 mm under the LHT, P = .003, and 38 ± 8 mm over the LHT, P = .004). The bipolar transfer course over the LHT was the nearest to the SS axis (39° ± 11°, P = .005). We found a greater axillary nerve overlap with bipolar transfer under the LHT (27 ± 8 mm) than with bipolar transfer over the LHT (1 ± 2 mm, P = .005) or monopolar transfer (0 mm, P < .001).

CONCLUSION

Bipolar TM transfer is possible without neurovascular pedicle interference, obtaining greater RC defect coverage and the closest path to the SS axis when conducted over the LHT compared with monopolar or bipolar transfer under the LHT. Accordingly, it can be considered an alternative option for the treatment of posterosuperior RC defects.

Surgical technique and anatomic study of latissimus dorsi and teres major transfers

BACKGROUND

Combined latissimus dorsi and teres major musculotendinous transfer has been described for the treatment of massive rotator cuff deficits. The procedure is technically complex because of the proximity of the radial nerve, the axillary nerve and its posterior branches, and the neurovascular bundles to the muscles. The purpose of the present cadaveric study was to examine surgically relevant relationships for latissimus dorsi and teres major tendon transfers.

METHODS

Twelve cadaveric shoulder girdles were dissected, and the latissimus dorsi, the teres major, and the posterior cord of the brachial plexus and its branches were identified. The relationships between the tendons and local neurologic structures were measured during various steps of the latissimus dorsi/teres major transfer procedure. The effect of humeral rotation on the exposure of the latissimus dorsi and teres major tendons through the posterior approach was quantified, and relevant surgical landmarks were described.

RESULTS

The radial nerve passed directly anterior to the tendons at an average of 2.9 cm medial to the superior aspect and 2.3 cm medial to the inferior aspect of the humeral insertions. From the posterior axillary approach, maximal internal rotation facilitated exposure for tenotomy by delivering the tendon insertions on the humerus into the surgical field. During axial mobilization of the musculotendinous units, the neurovascular pedicles to the latissimus dorsi and teres major were identified at an average of 13.1 and 7.4 cm axial to the humeral insertions, respectively. The posterior branch of the axillary nerve was noted to cross superficially over the transferred tendons as they were tunneled under the posterior deltoid.

CONCLUSIONS

Multiple steps of the combined latissimus dorsi and teres major musculotendinous transfer place local neurologic structures at risk. These steps include tendon release, musculotendinous axial mobilization, and tendon tunneling in the plane between the infraspinatus-teres minor and the posterior deltoid. We have quantified and described the relationship of the axillary and radial nerves to the tendons during tenotomy, the distance from the tendons' insertions to their neurovascular bundle that must be identified during axial mobilization, and the course of the posterior branch of the axillary nerve in relation to the tunneled path of the tendons.

CLINICAL RELEVANCE

The present study provides important anatomic findings for the safe mobilization and transfer of the latissimus dorsi and teres major tendons during the surgical treatment of irreparable rotator cuff tears.

A study for evaluating the effect of the deltoid-flap repair in massive rotator cuff defects

The repair of massive cuff defects by direct suture often is impossible. In these cases, a repair by musculo-tendineous flaps (latissimus-dorsi, pectoralis or deltoideus) is required. It was the goal of this study to evaluate the result of delta-flap repair in case of massive cuff defects with a diameter of 5 cm or more. Between 1998 and 2000 for all patients who were suffering from a massive rotator cuff tear more than 5 cm a deltoid transfer was performed. A total of 20 patients (14 male, 6 female; age: 60.9+/-8.7 years) were available for a follow-up after 47.2+/-8.0 (range, 36 to 60) month. The operation included an arthroscopic evaluation, acromioplasty with resection of the lateral clavicular end, and biceps tenodesis. The cuff defect was repaired by transfer a muscular flap from the anterior part of the deltoid (about 2 x 6 cm) into the defect. The patients subjectively rated their result-10 excellent, 9 good, and 1 poor. Preoperatively, the Constant amounted 26.3+/-5.1 points. At follow-up, the score significantly increased to 74.5+/-8.5 points. The acromiohumeral distance increased from 4.9+/-1.1 to 9.2+/-1.7 mm. In MRI examination of 11 patients all had an intact flap. Two complications (a wound hematoma and a deep infection) did not influence the result. The repair of massive rotator cuff tears by a deltoid transfer produces acceptable clinical and radiological results.

Elevator muscle of the tendon of latissimus dorsi muscle

Muscular dispositions in the axilla acquire importance under certain surgical procedures that involve the axillary artery ligature. These supernumerary muscles make the approach to the axillary fossa and their content difficult. We dissected 108 formalized corpses from adult male individuals. The specimens belong to the topographic Anatomy Unit of the Faculty of Medicine, Universidad de La Frontera, Chile. In all dissections, a rare and infrequent muscular variation attributed to the presence of a elevator muscle at the dorsal part of the latissimus muscle on the right upper limb from an adult individual was found. This muscle was fusiform and originated at the coracoid process by a short tendon of cylindrical form inserted in the dorsal superior part of the tendon of the latissimus dorsi muscle. Muscular belly and tendons of origin and insertion were closely related to the brachial plexus and the axillar vessels that they crossed.