Replantation



Replantation


Michael S. Gart



INTRODUCTION



  • The first upper extremity replantation was performed in Boston, MA by Dr Ronald Malt in 1962.1


  • Three years later, Komatsu and Tamai reported the first successful digital replantation.2


  • In order to be truly “successful,” a replanted part must function as well as or better than the available prosthetic technology.


  • Although surgeons can now technically replant nearly any severed part, recent focus has been on identifying patients who will have excellent functional outcomes following replantation.3


Pathoanatomy



  • An amputation in the upper extremity severs soft tissue, muscle/tendon, nerve, blood vessels, and bone.


  • The status of each of these structures will dictate the functional outcome of the replanted part(s).



    • In particular, severe nerve injury may preclude replantation, particularly with proximal upper extremity amputations, because an insensate extremity without motor function will ultimately be less useful than a prosthetic.


  • In digital amputations, the neurovascular bundles run volar to the mid-axis of the digit, between Grayson’s (volar) and Cleland’s (dorsal) ligaments.


  • Digital veins can be reliably located in the dorsal subcutaneous tissue.


  • Knowledge of the flexor tendon anatomy is critical because amputations through zone II will often have poor functional outcomes due to a high incidence of postoperative adhesions.


  • The thumb is responsible for nearly half of all hand function and, even with poor range of motion, a replanted thumb will provide the best functional outcome.4



Mechanism of Injury



  • Mechanism of injury is among the most important determinants of replantation success rates and ultimate functional outcomes.


  • Tool injuries (saws, agricultural machinery) are a common source of digital or hand/wrist level amputations.



    • New table-saw technology can stop a saw blade immediately upon contact with skin to reduce the potential for amputation.5


  • Polytrauma patients may present with crush or avulsion amputations.


  • Sharply amputated parts have higher rates of replantation success than crush or avulsion injuries.6,7,8 Ring avulsion injuries present a particular spectrum of injury and will be discussed elsewhere.


Epidemiology



  • In the United States, digits and thumbs account for the vast majority of upper extremity amputations; however, several hundred patients suffer more proximal amputations each year.


  • More than 45 000 traumatic digital amputations occur each year in the United States.9


  • Most patients suffering amputation are males, with a mean age of 40 years.10


  • Patients treated at large urban hospitals and/or academic medical centers are more likely to undergo replantation.10


  • African-American patients and uninsured patients are less likely to undergo replantation than Caucasian or privately insured patients.11


EVALUATION




Physical Examination



  • Every effort should be made to minimize the time from injury to definitive treatment.


  • The amputated parts and distal stump should be photographed and x-rays obtained prior to any attempted replantation (Figure 54.1).


ACUTE MANAGEMENT


Acute Patient Management



  • Patients presenting with traumatic amputations must be thoroughly evaluated by a trauma service for other life-threatening injuries, which take treatment priority.



    • Replantation is only considered in medically stable patients after appropriate resuscitation.


  • Any ongoing hemorrhage from the proximal stump should be controlled with external compression because vessel ligation or clamping can cause additional vessel damage.


  • Patients should be started on prophylactic antibiotics and given tetanus prophylaxis preoperatively.






FIGURE 54.1 Preoperative radiographs (A, B) and intraoperative photos (C, D) of multilevel hand and multiple digit amputation. Photos courtesy of Jason H. Ko, MD.







FIGURE 54.1 (continued)


Acute Management of the Amputated Part(s)

May 7, 2019 | Posted by in ORTHOPEDIC | Comments Off on Replantation
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