Abstract
Background Amputees frequently suffer from chronic pain in both their residual limbs (RLP) and
phantom limbs (PLP) following their amputation. Targeted muscle reinnervation (TMR)
is a nerve transfer technique that has been demonstrated to improve pain secondarily
and at time of amputation. The goal of this study is to report on the efficacy of
primary TMR at time of above-knee level amputations in the setting of limb-threatening
ischemia or infection.
Methods This is a retrospective review of a single-surgeon experience with TMR in patients
undergoing through- or above-knee level amputations from January 2018 to June 2021.
Patient charts were reviewed for the comorbidities in the Charlson Comorbidity Index.
Postoperative notes were assayed for presence and absence of RLP and PLP, overall
pain severity, chronic narcotic use, ambulatory status, and complications. A control
group of patients undergoing lower limb amputation who did not receive TMR from January
2014 to December 2017 was used for comparison.
Results Forty-one patients with through- or above-knee level amputations and primary TMR
were included in this study. The tibial and common peroneal nerves were transferred
in all cases to motor branches to the gastrocnemius, semimembranosus, semitendinosus,
and biceps femoris. Fifty-eight patients with through- or above-knee level amputations
without TMR were included for comparison. The TMR group had significantly less overall
pain (41.5 vs. 67.2%, p = 0.01), RLP (26.8 vs. 44.8%, p = 0.04), and PLP (19.5 vs. 43.1%, p = 0.02). There were no significant differences in complication rates.
Conclusion TMR can safely and effectively be performed at time of a through- and above-knee
level amputation and improves pain outcomes.
Keywords
TMR - neuropathic pain - phantom limb pain
