What’s the Claim?
A case series describing patients with late-presenting brachial plexus injuries, those in whom prior reconstructive efforts did not work, and those in whom free functioning muscular transfer was contraindicated, found that a triceps-to-biceps transfer gave nine of 12 patients some (3/5) biceps function (of whom five had 4/5 strength), with generally excellent average elbow ROM in flexion and a mean extension deficit of 11°. Three of 12 were rated as unsatisfactory, achieving only 2/5 strength. Three others were lost to follow-up.
A stable shoulder with active external rotation or static external rotation positioning — and (obviously) a functioning triceps — is needed to make this work. Note that this transfer takes the whole triceps, and so shouldn’t be used in patients who need that muscle to get around, such as those who need wheelchairs, canes, or crutches to ambulate.
While on the face of it those results seem decidedly so-so and the indications narrow, recall that these were a tough subset of an already-tough diagnosis, and some CORRelations readers don’t have the luxury of sending patients to the big university down the street.
How’s It Stack Up?
Several tri-to-bi transfers have been described, with results in the ballpark of this one, though it’s hard to compare these things — the indications and techniques varied, and the numbers generally were quite small.
So let’s focus on the key points of the approach in this paper:
- Protect the radial and ulnar nerves
- Elevate the distal triceps tendon off the olecranon
- For patients undergoing triceps tenodesis to the radius, whipstitch and tubularize the distal tendon
- Create a short anterior incision distal to the elbow flexion crease over the radial tuberosity to expose the biceps tendon insertion, make a radial-sided subcutaneous tunnel, and pass the triceps anteriorly
- Weave the triceps tendon into the biceps tendon using a Pulvertaft weave or perform a tenodesis with a biceps button, with the elbow flexed at 90° to 100°
- When using a button tenodesis, the insertion point is radial to the biceps tendon insertion, and the biceps button is secured and deployed after tensioning with the elbow in 90° to 100°; side-to-side tenodesis of the biceps-to-triceps tendon is performed, and fluoroscopy confirms the position of the tenodesis button
- The elbow is maintained at 90° of flexion during closure, and a posterior long-arm splint maintaining 90° to 100° is applied
- Aftercare involves immobilization in that position for 6 weeks, followed by a hinged elbow brace for 6 weeks during which extension is increased 10° per week until 30° of passive extension is obtained; active elbow flexion is encouraged in the brace
What’s Our Take?
Case series and technique articles have their place in our specialty. That said, we usually avoid them here for reasons you’ve seen us write about before — selection bias, loss to follow-up, and assessment bias, among many other problems.
But sometimes, they’re just what you need and all you’re gonna get, particularly for uncommon and difficult problems. This is one of those times. CORRelations’ advisor in Hand, Desirae McKee, MD, describes this as a “good technique paper that even nonspecialty surgeons can use to help restore elbow flexion in patients who cannot get to a subspecialist, though it's important to recognize that good, attentive, expert therapy is essential after this procedure.”
Weber MB, Wu KY, Spinner RJ, Bishop AT, Shin AY. Triceps-to-Biceps Tendon Transfer for Restoration of Elbow Flexion in Brachial Plexus Injury. J Hand Surg Am. Published online August 2, 2023. DOI: 10.1016/j.jhsa.2023.06.020.