Volumetric muscle loss/soft tissue loss
Immediate massive skin and soft tissue loss, and necrosis of crushed or ischemic tissue after injury requiring debridement(s), is not an absolute indication to perform early amputation. Loss of dynamic tissues such as muscle and tendon may compromise function, but anatomic redundancy, compensation, allografts, tendon transfers and bracing can maintain or restore function even in the face of major losses. Massive skin defects can also be managed with free tissue transfers, autografts and allografts and an increasing number of bioengineered membranes. Negative-pressure wound therapy provides temporizing capabilities, promotes intrinsic biologic healing processes and may improve surgical repair success.
Crush injury releasing products of necrosis into the circulatory system may cause renal compromise, multi-system organ failure, circulatory collapse, and death. Despite performing timely surgical intervention or amputation when these problems manifest clinically, irreversible organ damage or death may result. The decision to pursue limb salvage instead of immediate amputation at the time of severe crush injury will sometimes result in avoidable organ loss or death, but these negative outcomes cannot be predicted in an individual patient at the time of injury.
In 2005, MacKenzie et al (as a part of the LEAP study), analyzed 397 patients and showed volumetric muscle loss was associated with a worse Sickness Injury Profile (SIP) score at 84 months after injury, but did not adversely affect limb salvage.
Crush and/or blunt injury was investigated by SM Melton in 1997, TN Hutchison in 2014, and EE Low in 2017, and showed no impact on limb salvage versus amputation. There was a significantly increased risk of pulmonary embolism (PE) (Hutchison) and need for amputation revision (Low) in the 2014 and 2017 studies, which had 1003 and 2314 patients, respectively.
T. Melcer et al (2017) studied 625 patients with lower limb blast injury and showed no impact on limb salvage. Pain and subsequent osteoarthritis were more common in this type of injury, but they found no increases in PE, infection, or osteomyelitis. Penetrating injury did raise the risk of VTE (Hutchison, 2014)
A. Jain in 2013 looked at lower extremity de-gloving injuries in 40 patients who underwent amputation. This injury type had no significant impact on amputation infection rates.
BENEFITS & HARMS:
Massive muscle and soft tissue loss may complicate or prolong the limb salvage pathway. Ultimate functional outcome may be compromised by the loss of muscle/tendon units and other mechanically important structures.
Cost data clearly show a successful limb salvage patient incurs significantly lower lifetime medical costs compared to amputation.
Some patients with massive soft tissue injury who do not undergo immediate amputation will ultimately have permanent organ failure, septic shock, and/or death. At time zero, there are no factors which can prospectively identify these patients.
Patients who undergo successful limb salvage will retain a useful extremity, with significantly less lifetime medical expense.
COST EFFECTIVENESS/RESOURCE UTILIZATION:
Successful limb salvage in the setting of severe soft tissue injury may result in higher short-term costs related to multiple surgical procedures, wound management, and prolonged hospitalization. Lifetime medical expenses will be lower compared to amputation.
Pursuing limb salvage in cases of massive soft tissue loss/injury may strain resources at initial point of care, especially in mass-casualty scenarios. Temporizing measures for massive soft tissue injury may be unavailable. Time zero medical personnel may fear being judged retrospectively in cases of ultimate fatality or permanent organ damage in massive crush injuries.
Adequate resources for massive soft tissue injuries need to be available at initial point of care. These include temporizing coverage options (negative pressure dressings, allograft or engineered tissue coverings) and personnel skilled in wound management using these techniques.
Studies of attempted limb salvage patients who progress to septic shock, permanent organ damage, and death should focus on predictive tools and clinical and laboratory findings which identify failing limb salvage situations, where timely conversion to amputation prevents organ death and/or patient demise. Studies which look at mechanism of injury, specific and quantifiable anatomic structure soft tissue damage or loss in lower extremity injury, may allow identification of patients at initial presentation who have predictable bad outcomes.
- Hutchison, T. N., Krueger, C. A., Berry, J. S., Aden, J. K., Cohn, S. M., White, C. E. Venous thromboembolism during combat operations: a 10-y review. J Surg Res 2014; 2: 625-30
- Jain, A., Glass, G. E., Ahmadi, H., Mackey, S., Simmons, J., Hettiaratchy, S., Pearse, M., Nanchahal, J. Delayed amputation following trauma increases residual lower limb infection. J Plast Reconstr Aesthet Surg 2013; 4: 531-7
- Low, E. E., Inkellis, E., Morshed, S. Complications and revision amputation following trauma-related lower limb loss. Injury 2017; 2: 364-370
- MacKenzie, E. J., Bosse, M. J., Pollak, A. N., Webb, L. X., Swiontkowski, M. F., Kellam, J. F., Smith, D. G., Sanders, R. W., Jones, A. L., Starr, A. J., McAndrew, M. P., Patterson, B. M., Burgess, A. R., Castillo, R. C. Long-term persistence of disability following severe lower-limb trauma. Results of a seven-year follow-up. J Bone Joint Surg Am 2005; 8: 1801-9
- Melcer, T., Walker, J., Bhatnagar, V., Richard, E., Sechriest, V. F., 2nd, Galarneau, M. A Comparison of Four-Year Health Outcomes following Combat Amputation and Limb Salvage. PLoS One 2017; 1: e0170569
- Melton, S. M., Croce, M. A., Patton, J. H., Jr., Pritchard, F. E., Minard, G., Kudsk, K. A., Fabian, T. C. Popliteal artery trauma. Systemic anticoagulation and intraoperative thrombolysis improves limb salvage. Ann Surg 1997; 5: 518-27; discussion 527-9