General Information

Rehabilitation Following Peripheral Nerve Surgery
There is growing awareness of the importance of rehabilitation for nerve transfer surgery. Even with proper surgical candidate selection and successful recipient muscle reinnervation after surgery, the desired outcome may not be achieved without targeted rehabilitation. There are issues that are unique to patients undergoing nerve transfer rehabilitation. Accordingly, several groups have developed frameworks for structured rehabilitation.66–70 Although each of these frameworks have their nuances, they are similar in defining the trajectory and individual phases of rehabilitation. The time course and general phases of rehabilitation are presented in Figure 4. The following is a discussion of several key considerations in rehabilitation following nerve transfer. 

“Prehabilitation” 
One of the most important aspects of nerve transfer rehabilitation is preoperative preparation or “prehabilitation.” Individuals with peripheral nerve injury (PNI) and SCI often develop secondary complications that could negatively impact rehabilitation, if not adequately addressed. Notably, PNI and SCI are associated with a high prevalence of neuropathic pain, mood disturbance, contracture, and edema.71–74 These complications should be serially addressed and mitigated prior to surgery. Another major consideration is patient education regarding the procedures being proposed and the expected time course of recovery. Patients should be made aware of the unique anatomical considerations of the procedure (see section on Donor Activation below), so they understand the muscle actions that will be required to facilitate rehabilitation. Patient expectations about recovery should also be addressed. This includes discussion of the lengthy recovery period (2-3 years after surgery), as well as the long delay until reinnervation and observable movement. Prehabilitation considerations carryover into the early postoperative period, where mitigation of edema, contracture, and pain are critical, before reinnervation takes place at approximately 6 to 9 months after surgery.68 

Donor Activation 
A unique aspect of nerve transfer rehabilitation is the goal of “repurposing” a donor nerve/fascicle toward a new recipient action (see Figure 3). This is known as donor activation.74 Donor activation requires substantial cortical plasticity, and it has been proposed that the effectiveness of nerve transfer surgery may be dependent on the success of cortical remodeling.75,76 

Donor activation strategies are required during the entire course of rehabilitation in order to achieve the end goal of activation of the recipient muscle group against resistance independent of donor action. In the prehabilitation and early rehabilitation periods, the emphasis should be on visualization of recipient actions, in conjunction with the performance of the donor action. “Flooding the donor” to strengthen the cortical representation and reduce donor morbidity has also been suggested.69 Once reinnervation occurs, a patient should begin to co-contract the donor and recipient together, with gravity eliminated. As reinnervation continues, the goal is to perform the recipient actions against gravity/resistance, independent of the donor action. Adjunctive techniques to facilitate cortical plasticity in the early phases of rehabilitation, including biofeedback, electrical stimulation, and mirror therapy have been described, although they lack high-level evidence at present.68,69 

Interdisciplinary Care 
Due to the complex needs of the patient populations undergoing nerve transfer surgery, rehabilitation should be undertaken in an interdisciplinary setting. Many Canadian centers have adopted an interdisciplinary care model whereby patients are seen by their peripheral nerve surgeon, neurologist, physiatrist, and physio/occupational therapist in a single encounter.77,78 Our recommended care pathway includes serial postoperative follow-up with the entire healthcare team, typically at 3- to 6-month intervals, depending on individual needs. This can include postoperative electrodiagnostic testing to demonstrate the extent of reinnervation and inform prognosis.

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