Thankfully high-pressure injection injuries to the hand are uncommon because they have the potential to cause devastating consequences. To complicate things, these injuries often look innocuous with their initial presentation. Despite this innocuous looking injury, these accidents should be treated as limb-threatening injuries and immediately referred to a hand surgeon.
The three most common devices responsible for these injuries are:
Mason and Queen in 1941 divided the clinical findings into three states:
- The immediate symptoms result from the injection of the foreign material are swelling, numbness, and vascular insufficiency.
- This distention of the tissues may cause a pressure buildup that exceeds hydrostatic pressure, limiting tissue perfusion similar to that in compartment syndrome.
- The chemical injury caused by the substance itself may result in tissue destruction and an inflammatory reaction (which leads to more swelling, which may further compromise the tissue perfusion)
- Infection may occur in the necrotic tissue or from contamination from the substance injected.
- Initially, the patient may complain only of mild pain and may even continue working, leading to a delay of care. The injured area may at first seem inconspicuous, presenting as a small pinprick, and caregivers who may not be familiar with this injury may regard it as insignificant. The finger eventually becomes painful, numb, bloated, edematous, tense, pale, and cold.
- Radiographs may help assess the extent of the spread of the injected material, which may present as air in the soft tissue, or as radiopaque material in other cases.
- Oleomas often develop following the acute phase. These are nodular "tumors" that develop as a result of a foreign body reaction to the injected material.
- Oleomas may remain unchanged for years, but fibrosis often occurs with them, leading to loss of function. Because of this, oleomas should be excised completely along with any fibrosis associated with them.
- Skin overlying the untreated oleoma may breakdown. This may lead to ulcer and draining sinus formation.
- The skin becomes thick and pitted.
- The ulcers and draining sinuses may become infected.
- Development of squamous epithelioma in the sinuses have been reported.
The following guidelines are suggested for optimal treatment:
1. Early medical evaluation, including radiographic studies.
8. Wound cultures when appropriate to direct antibiotic therapy.
13. Early postoperative hand therapy to maximize functional outcome.
Prevention of these injuries is the best.