Table 1 Summarizes pearls and pitfalls of currently reported technique of middle trapezius tendon transfer; EAU examination under anesthesia, GH gleno-humeral, LHB long head of biceps, ISP infraspinatus, RC rotator cuff, SSC subscapularis, SSP supraspinatus
Pearls: | |
*Setup -Beach-chair position with accessible back of the shoulder (notably, medially up to the dorsal spine) -EAU (for exclusion of frozen shoulder) | |
*Diagnostic arthroscopic GH examination | |
*Arthroscopic sub-acromial decompression | |
*Hamstring tendon autograft harvesting -Common insertion of harvested gracilis and semitendinosus tendons is detached with a part of related periosteum to get a tendon graft of about 22-24 cm in length. | |
*Hamstring tendon autograft fashioning -Each harvested tendon is folded over itself to have a quadruple sheet of a length not less than 12 cm. -For re-enforcement/sheet-fashioning, folded tendons are side-by-side sutured by # 2 absorbable sutures | |
*McKenzie approach -Remnant sub-acromial bursa is excised by to improve visualization during next steps -Footprint of RC is well-prepared to improve biology for healing of future tendon reconstruct. -Tension-free anatomic/partial/medialized RC (ISP+/−SSP) repair is performed -Free suture limbs of RC repair are left uncut for later suturing of the hamstring sheet to the repaired RC -When concurrently torn, SSC is anatomically repaired to its footprint -Soft-tissue tenodesis of tenotomized LHB to repaired RC | |
*Middle trapezius tendon release -Skin overlying medial half (5-6 cm) of the scapular spine is transversely incised -Medial portion (5-6 cm) of middle trapezius insertion is identified, stay-sutured, and released (with related periosteum) from scapular spine by diathermy in a lateral-to-medial direction till medial scapular border -To improve its excursion, undersurface of released tendon is bluntly dissected (by sweeping finger) from underlying atrophic SSP | |
*Sub-trapezius/sub-acromial passage of the hamstring sheet -A long straight artery clamp is passed via McKenzie approach deep to the acromion to the scapular wound to establish a sub-trapezius/sub-acromial corridor to retrieve hamstring sheet from the scapular to the humeral sides. | |
*Re-attachment of the hamstring sheet on the humeral side -Periosteal end of the hamstring sheet is trans-osseously sutured to anatomic footprint of RC (notably of SSP) by #5 non-absorbable sutures and to the repaired RC by uncut free suture limbs of suture anchors used for RC repair. | |
*Re-attachment of the hamstring sheet on the scapular side -While retracting the scapula and placing GH joint in 45O-abduction/45O-external rotation position, hamstring sheet is sutured (in Pulvertaft/ side-to-side fashion) to released middle trapezius tendon by #5 non-absorbable sutures | |
*Dynamic testing of the construct -For: integrity and smooth sub-acromial gliding motion of the tendon reconstruct -By: placing GH joint in different positions of range of motion and by axial loading of tendon reconstruct | |
Pitfalls: | |
-Suture-tagging of medial insertion of middle trapezius (prior to harvesting) is to facilitate its release and excursion testing -Medial insertion of middle trapezius should be released in a sub-periosteal fashion to harvest tendon stump able to withstand Pulvertaft/side-to-side suturing; otherwise; integrity of the tendon reconstruct is to be compromised -Release of medial portion of middle trapezius should not exceed medial scapular border to avoid spinal accessory nerve injury -Short harvested medial insertion of middle trapezius is to subject the tendon reconstruct to excessive tension -Capacious sub-trapezius/sub-acromial corridor is to ensure free smooth sub-acromial gliding motion of the tendon reconstruct -Adequate length (for future attachment on both humeral and scapular sided) of the hamstring sheet should be evaluated following its sub-trapezius/sub-acromial passage |