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Page 2 of 22 Vakhshori et al. Plast Aesthet Res 2023;10:36 https://dx.doi.org/10.20517/2347-9264.2022.78

or congenital loss of elbow motion, as in arthrogryposis. When muscles required for elbow flexion
(specifically biceps brachii and brachialis) are viable, nerve transfers or grafts may be an option for
[1,2]
restoration of elbow flexion . However, in cases of chronic injuries, muscle loss, atrophy, fibrosis, or
extensive brachial plexus injury, nerve transfer or graft may not be sufficient to restore elbow flexion. In
these cases, muscle transfer options should be considered . Restoration of elbow flexion should be
[1]
[3]
prioritized to restore function to the upper extremity, followed by finger flexion and finger extension . In
general, a single transferred muscle should provide a single function, though in the case of severe brachial
[3]
plexus injury, this may be impossible due to limited numbers of donor nerves .
INDICATIONS
A pedicled latissimus transfer for restoration of elbow function was first described by Schottstaedt et al. in
1955 and Hovnanian in 1956 . Since that time, numerous studies have examined various options for
[4,5]
functional muscle transfers. Free muscle functional muscle transfers were used by Manktelow and McKee in
1978 and Zuker et al. in 1991 to restore upper extremity function . As techniques have progressed,
[6,7]
functional muscle transfers can now be used for restoration of shoulder flexion, elbow flexion, elbow
extension, finger flexion, finger extension, and thumb motion, either in isolation or in combination to
restore muscle functions [8-10]

Patients who are being considered for functional muscle transfer must be motivated and willing to perform
the extensive postoperative therapy and rehabilitation required for maximizing function. The recipient site
requires full passive motion at the joint the transfer will move, in addition to a soft tissue bed conducive to
muscle and tendon gliding. Healthy donor nerves and vessels are required. Functional muscle transfer
should be used when no nerve or tendon transfer options are available. Patient age is an additional factor to
consider -- while children are more likely to have successful restoration of motor function, there may be a
mismatch in growth between the transferred muscle and the humerus, potentially leading to elbow
[9]
contracture as the child reaches skeletal maturity . Stevanovic and Sharpe recommend an age limit of 45
years old for free functional muscle transfers to optimize recovery of motor function However, Doi et al.
[9]
showed success after free functional muscle transfer in patients aged 62 years old and younger, while
Ihara et al. had successful outcomes up to age 65 [11,12] . Additional factors that are detrimental to outcomes,
especially in free muscle transfers, include diabetes, vascular disease, cardiac disease, autoimmune
conditions, smoking, and obesity .
[9]

DONOR MUSCLES
Several donor muscle options are available for restoration of elbow flexion. In the setting of vascular
compromise from trauma or irradiation, a pedicled latissimus is preferred to restore elbow flexion without
the need for an arterial anastomosis. The pedicled transfer is technically less challenging as it does not
require a microvascular anastomosis. When a free flap is required, such as in the case of poor ipsilateral
latissimus function, the gracilis is the most commonly used donor muscle. The gracilis has a redundant
function in the lower extremity, making it more suitable for transfer than other lower extremity donor
muscles. Its size and excursion make it ideal for restoration of upper extremity function, where it may be
used in the forearm for restoring wrist or digit flexion or extension, or in the upper arm for restoring elbow
flexion.

Latissimus dorsi (pedicled)
The latissimus dorsi muscle is a versatile option for restoring elbow flexion. It can be performed as a
rotational muscle transfer or free functional muscle transfer from either the ipsilateral or contralateral side.
Prior to surgery, the function of the latissimus muscle must be tested to ensure the transferred muscle can