Injury to R hand
51yo right hand dominant man presents one hour after high-pressure epoxy paint gun accidental injury to right hand. Patient states that while testing a paint gun, a stream of paint hit his hand causing 2 puncture wounds to his palm. Denies paresthesias, weakness. Patient complains of swelling to area of puncture with mild bleeding.
VS: BP 151/98 HR 88 RR 16 SpO2 99%RA Tc 98.0
– Two 2mm puncture wounds over volar aspect between 2nd and 3rd MCP joints at level of A1 pulley
– Radial pulse palpable, all digits warm and well perfused with
– SILT r/u/m
– FDS/FDP intact in digits 2-5
– AIN/PIN/U intact
– No extensor lag
– Compartments of hand are soft, no pain on passive extension
What are the important physical exam features of this injury?
A non-impressive physical exam such as the patient in the case is not uncommon with high-pressure injection injuries. Look out for any obvious signs of neurovascular compromise and compartment syndrome. However, the absence of significant exam findings does not suggest a benign injury.
What are the most likely complications of this injury?
Complications from this type of injury range from decreased long-term functionality to required amputation of the area of injury (finger or limb) due to vascular thrombosis, tissue necrosis, and compartment syndrome.
What is the best management of this patient?
High-pressure injection injuries require broad-spectrum antibiotics and urgent surgical debridement.
High-pressure injection hand injuries from paint, fuel, or hydraulic fluid guns can result in devastating consequences. However, its benign appearance on presentation often fools patients and physicians alike to dismiss its clinical significance. Patients frequently present with unassuming small puncture wounds with minimal or no pain1-4. On average, patients take up to 9 hours prior to seeking medical attention and one study found some patients will see up to seven physicians before receiving appropriate management4. Fortunately, these injuries occur rarely and only found in about one in six hundred hand traumas4.
Injected substances travel along paths of least resistance usually along tissue planes, around neurovascular bundles and can penetrate much deeper than what appears on physical exam. One case report found a man with pneumomediastinum caused by high-pressure injection injury to the hypothenar region where injected material had traveled along the ulnar artery to the brachiocephalic artery to the aortic arch and ultimately to the posterior mediastinum4.
Damage to the affected tissue is two fold: mechanical and chemical1-2,4. Once a substance is injected into a potential space, there is mechanical compression of the neurovascular bundle causing venous hypertension and decreased perfusion, which can cause leaking from capillaries that cause more edema and compression in a self-perpetuating destructive cycle1-2,4. Compression of the vasculature can lead to eventual vasospasm, vascular thrombosis and tissue necrosis. Substances other than air and water have inherent cytotoxic properties that cause local and sometimes systemic inflammation, which synergistically induce edema with mechanical compression that can result in compartment syndrome1-2,4. Oil based paint appears to be one of the most cytotoxic substances, so much so that some authors recommend primary amputation as first line of treatment4. Tissue necrosis and the general ischemic environment create a nidus for secondary infection. In a recent metaanalysis, it was found that 42% of intraoperative samples grew positive cultures despite initiation of early broad-spectrum antibiotics3. Most cultures grew polymicrobial organisms1-4.
Amputation rates can be as high as 88% depending on location of injury and time to surgical debridement3. Injuries to the index finger result in higher amputation rates when compared to thumb and more proximal aspects of the hand3. In a review of 435 cases, Hogan et al found that amputation rate is proportionate to time to surgical debridement. The amputation rate for injection injuries to the upper extremity undergoing surgical debridement within 6 hours of initial injury averaged 38% when compared to an amputation rate of 58% when surgical debridement is delayed more than 6 hours and a devastating 88% when debridement did not occur for more than one week3. Surprisingly, concomitant infection did not affect amputation rates3.
Due to ethical considerations, no randomized controlled trials exist to guide treatment of this injury. All data obtained are derived from case studies and case series3. In the Emergency Department, initial management includes elevation of the limb, tetanus vaccination, analgesia, and initiation of broad-spectrum antibiotics covering both gram positive and gram negatives. Plain films can be helpful to track spread of injected material if the substance injected is radiopaque4. However, do not be reassured if no radiopaque tracking is elucidated on plain film as plain film may not reveal the degree of tracking and the substance injected may be radiolucent4. Of note, to prevent further damage to the injured limb, avoid digital blocks that may increase vasospasm, ice that can decrease perfusion, and primary closure of the wound4. Conservative management of high-pressure injection injuries can be pursued in injection of air or water as there are case reports of return to normal function without surgical debridement3,4. If the patient suffered injection of anything else other than air or water, timely surgical debridement must occur in order to assure the best possible functional outcome3,4. Urgent surgical debridement and exploration has been the standard of care since the original case report in 19374.
- Patients presenting with high-pressure injection injuries can have essentially a normal exam. Physical exam is not a reliable measure of the degree of injury.
- High Pressure injection injuries can result in high amputation rate if not treated appropriately in a timely manner.
- Urgent surgical debridement and exploration is the standard of care. Patients should also receive tetanus vaccination and broad-spectrum antibiotics.
- Amsdell SL, Hammert WC, High-pressure injection injuries in the hand: current treatment concepts, Plast Reconstr Surg, 2013 Oct;132(4):586e-591e.
- Chaudhry S, Gould S, Gupta S, High-pressure paint gun injection injury to the palm, Am J Orthop (Belle Mead NJ), 2013 Aug;42(8):379-82.
- Hogan CJ, Ruland RT, High-pressure injection injuries to the upper extremity: a review of literature, J Orthop Trauma, 2006 Jul;20(7):503-11.
- Rosenwasser MP, Wei DH, High-pressure injection injuries to the hand, J Am Acad Orthop Surg, 2014 Jan;22(1):38-45.