The first published case of an injection injury to the hand was in the German literature in 1925 by E. Hesse1. High-pressure delivery systems had followed the increasing mechanization of industry at the beginning of the 20th century. Although these systems are an essential part of today's industry, they are associated with rare but severe injuries. A pressure of 100 pounds per square inch is required to penetrate the skin2. Modern high-pressure equipment can easily surpass this pressure and deliver material into the body.
Small case series of high-pressure injection injuries have accumulated in the literature since the first report in the English literature by Rees in 19373. Although none of these provide statistically significant data, there is agreement among the majority of authors that the standard of care is early surgical decompression, debridement, and broad-spectrum antibiotics. This article will provide an overview of the mechanism of injury and treatment recommendations for patients with high-pressure injection injuries.
High-pressure injection injuries involving substances that contain organic solvents have a much worse prognosis than those involving substances that are more inert. Oil-based paint and paint thinner have been commonly considered the worst offenders; they have an amputation rate of over 50%. Conversely, grease is much less toxic and can have a more indolent course4. There have also been instances of high-pressure injection with water and air in which amputations were not reported5,6.
Mason and Queen7 described three stages to the inflammatory process resulting from an injection injury: acute inflammatory, intermediate granulomatous, and chronic ulcerative.
- In the acute phase, mechanical compression and chemical irritation contribute to the pain, swelling, and vascular compromise of the affected body part.
- As the body reacts to the foreign material retained after an injection injury, granulomas and late fibrosis can cause contracture. This intermediate granulomatous phase can also produce oleomata that may persist unchanged for many years.
- In developed countries, patients seek medical attention before the late phase of chronic ulcers. These are a result of oleomata that erode through the covering skin and create ulcers and sinuses. Secondary infection increases inflammation and skin loss.
A narrow, high-pressure stream of injectate produces a small punctate lesion in the skin, which can appear innocuous initially. Injection into a finger usually causes very little pain, but the finger will be edematous and passive and active motion will be impaired. Frequently a small amount of injected material can be expressed from the wound upon manipulation of the finger. These injuries initially produce little pain and do not appear severe. Victims will often delay seeking medical assessment, and these injuries can be underestimated by emergency department personnel.
Injuries with oil-based paint, paint thinner, or other organic solvents will typically produce severe pain within the first several hours. Victims may return to work for some time after the injury but will present to an emergency department with increasing pain and swelling.
Grease or diesel fuel may produce very few symptoms. There have been reports of victims delaying care for months after injection injuries with grease, at which time an intense chronic inflammatory reaction has developed. These patients often have severe fibrosis and contractions of their hands. Retained grease can also produce foreign body reactions resulting in oleomas that are often adherent to tendons and neurovascular bundles7.
As with any trauma, a full history and physical should be performed. These patients can develop a systemic reaction to the solvent8. Therefore, any signs of shock should be addressed. After life-threatening trauma has been ruled out, careful attention should be directed toward the material injected, the mechanism of injection (ie, paint gun, ruptured pressurized hydraulic line, high-pressure water sprayer), and time of injury. The patient should be asked about the pressure of the machinery, although this is often unknown.
A proper hand injury history also includes hand dominance, occupation, hobbies, and other pertinent comorbidities (ie, diabetes, vascular disease, smoking). The material safety data sheet (MSD sheet) should be obtained from the work site if possible. Radiographs can provide information on the extent of proximal spread of the injected material or air. Even in injuries with radiolucent material, injected air can often be seen and aid planning of appropriate treatment.
Motor and sensory examination should be performed to assess damage to neurovascular structures in the digits. Mottled, cool skin can provide evidence of vascular compromise. If the patient has delayed seeking treatment for an extended period after injury, the entire limb should be closely examined for compartment syndrome. The intrinsic compartments of the hand and the anterior compartment of the forearm are especially susceptible to produce secondary vascular compromise.
Early recognition is one of the most important factor in the management of this condition. The time to treatment is one of the few variables that can be controlled by the physician. It has been reported that the amputation rate for oil-based paint or paint thinner is 58% if time between injury and debridement exceeds 6 hours4. The amputation rate when surgery was fewer than 6 hours after injury was 38%. Paradoxically, Lewis9 reported higher amputation rates for injuries with a shorter time to the operating room. This is possible because trips to the OR were expedited for injuries that appeared grossly severe. We recommend that the patient be taken to surgery as quickly as possible.
A high-pressure injection injury of the hand is a surgical emergency. Emergency room staff should provide tetanus prophylaxis, broad-spectrum antibiotic coverage, obtain radiographs, and elevate the hand. Ideally, a hand surgeon should be contacted immediately. In hospitals without a hand service, the on-call surgeon should be notified immediately. Local anesthesia and warm compresses or soaks are contraindicated because they can exacerbate the inflammatory and ischemic effects of the injected material. The patient should be counseled on the severe nature of this injury. He should be informed of the risk of amputation and the likelihood of functional loss, thus stressing patient motivation and cooperation in the post-operative course.
The role of steroids in the treatment of high-pressure injection injuries remains controversial10,4. Intuitively, anything that can reduce the inflammatory reaction would help the patient, and animal studies confirm that steroids reduce inflammation associated with injection injuries. Some authors cite the increased risk of infection as a reason to avoid their use. Schoo et al11, reported that immediate high-dose steroids were routinely given to their patients and infection was not a problem in their series. Hogan and Ruland report that animal models support the use of steroids.
Operative intervention should be performed under general or regional anesthesia. Digital blocks are contraindicated12. Exsanguination of the extremity should be done with elevation for at least 4 minutes, followed by tourniquet. Esmarch's wrap is contraindicated because of the risk of driving the injected material further throughout the tissues. Full exposure of the injected tissues is crucial to adequately treating these injuries. Digits should be opened with Bruner's incision or a modification that can be extended into the palm, wrist, and forearm if necessary. Tendon sheaths, if involved, should be opened while preserving the critical A2 and A4 flexor pulleys.
The importance of meticulous removal of all injected material and devitalized tissue cannot be overstated. Injected materials can continue to cause deleterious reactions as long as they are in contact with tissue. Beckler13 suggests that the operating microscope be utilized in all cases of injection injury debridement. We recommend magnification with loupes.
After removal of all visible foreign material and necrotic tissue, the wound should be copiously irrigated with normal saline or lactated Ringer's solution. Irrigation with another solvent would prolong irritation of the tissues and is contraindicated. The wound should be closed loosely or left open. A continuous irrigation system can be used. Interval debridement of the digit and hand should continue until complete cleansing of the tissue has occurred. In severe injuries, this process may take days or weeks.
Once the surgeon is confident that the wound is clean and tissue viable, closure can be performed. Because of the tenuous nature of the remaining tissue, rotational flaps from adjacent parts of the hand have become a favored technique to cover the injured area14. This provides a more secure blood supply to the injured area than partial thickness skin grafts. Skin grafting may be necessary in some cases with large defects.
Rehabilitation should begin early15. It is essentially impossible to remove all material that was injected. Mobilization within 48 hours will reduce contracture and fibrosis stimulated by retained foreign body. The tendon and nerve bundles are usually intact despite the widespread soft tissue damage and early passive motion is tolerated by patients. As the suture lines heal, passive movement and hydrotherapy can be added.
Four Cases of High-Pressure Injection Injury of the Hand
- Hesse. Die chirurgische und gerichtichmedizinische bedeutung der kunstlich hervogerufenen erkrankungen. Arch Klin Chir. 1925;136:277-291.
- Scott AR. Occupational high-pressure injection injuries: pathogenesis and prevention. J Soc Occup Med. 1983;33:2:56-59.
- Rees CE. Penetration of tissue by fuel oil under high pressure from diesel engine. JAMA. 1937;109:866-867
- Hogan CJ, Ruland RT. High-pressure injection injuries to the upper extremity: a review of the literature. J Orthop Trauma. 2006;20:7:503-511.
- Christodoulou L, Melikyan EY, Woodbridge S, Burke FD. Functional outcome high-pressure injuries of the hand. J Trauma. 2001;50:4:717-710.
- Peters W. High-pressure injection injuries. Can J Surg. Oct 1991;34(5):511-513.
- Mason ML, Queen FB. Grease gun injuries to the hand:pathology and treatment of injuries (oleomas) following injection of grease under presssure. Quart Bull Northwestern Med Sch. 1941;15:122-132
- Kaufman HD, Williams HO. Systemic absorption from high-pressure spray gun injuries. Br J Surg. 1966;53:1:57-58.
- Lewis HG, Clarke P, Kneafsey B, Brennen MD. A 10 year review of high-pressure injection injuries to the hand. _J Hand Surg (Br)_. 1998;23B:4:479-481.
- Wong TC, Ip FK, Wu WC. High-pressure injection injuries of the hand in a Chinese population. J Hand Surg (Br) 2005;30:588-592.
- Schoo MJ, Scott FA, Boswick JA. High-pressure injection injuries of the hand. J of Trauma. 1980;20:3:229-238.
- Stark HH, Ashworth CR, Boyes JH, Mirzayan R, Schnall SB, Chon JH, Holtom PD, Patzakis MJ, Stevanovic MV. Culture results and amputation rates in high-pressure paint gun injuries of the hand. _J Bone Joint Surg Am_. 1967;49:4:637-647.
- Bekler H, Gokce A, Beyzadeoglu T, Parmaksizoglu F. The surgical treatment and outcomes of high-pressure injection injuries of the hand. _J of Hand Surg (Eur)_ 2007;32E:4:394-399
- Puhaindran ME, Chong AKS, Chew WYC. Flap recontruction following high pressure injection injuries of the hand: A report of three cases. _Hand Surg_. 2004;9:2:211-219.
- Palmieri TJ. High-pressure injection injuries of the hand, treatment by early mobilization. Bull Hosp Joint Dis. 1974;35:18-35.