Operative and Non-operative Treatment of Traumatic Arthrotomies: A Prospective Observational Study

Background and Rationale Soft tissue wounds around joints are common injuries that are carefully evaluated to identify intra-articular extension. Wound exploration, imaging, and intra-articular saline load injections are commonly utilized to diagnose the presence of a traumatic arthrotomy. The reason for such diligence is that the treatment is dramatically different for a wound that violates the joint compared to one that does not. As opposed to local wound care for simple soft tissue wounds, traumatic arthrotomies are thought to require formal irrigation and debridement in the operating room to minimize the risk of developing septic arthritis.

Septic Joints An injury that penetrates the joint capsule and synovium violates the body's natural barriers that protect the joint from external pathogens. Microorganisms from the environment may enter the joint by direct inoculation or by contiguous spread through the now perforated barrier. By bringing patients to the operating room for formal irrigation and debridement, orthopaedic surgeons are theoretically attempting to minimize the burden of contamination and repair the body's natural barriers to reduce the risk of developing an intra-articular infection. Septic arthritis is an orthopaedic emergency that can result in severe cartilage damage causing long-term joint pain, stiffness, and potentially auto-fusion. If not dealt with in a timely manner, intra-articular infections can result in significant long-term disability, and in extreme cases, can result in overwhelming sepsis and death.

Orthopaedic Dogma Clearly, minimizing the risk of developing septic arthritis is important to every orthopaedic surgeon. Over sixty years ago, observation of a high rate of septic complications in combat injuries that violated the joint. Since then, orthopaedic dogma has dictated that all injuries that violate the joint necessitate formal irrigation and debridement in order to minimize the risk of infectious complications. The literature on the topic is sparse and stems primarily from wartime observations in which the injuries sustained were commonly associated with high levels of contamination, intra-articular fractures, retained foreign bodies, and delayed treatment. The characteristics of these injuries may limit the generalizability of these observations to the civilian population, especially for small, mildly contaminated arthrotomies without associated fracture or retained foreign body.

To date, no studies have prospectively evaluated the benefits of operative irrigation and debridement of traumatic arthrotomies compared to non-operative observation with antibiotics. A single study published showed that patients with open joint injuries treated with operative irrigation and debridement had an infection rate of 2.1%, a value significantly lower than was previously observed in the non-operative cohort of combat injuries. There is little question that large and heavily contaminated arthrotomies benefit from formal irrigation and debridement, but it is unclear if this benefit can extrapolated to smaller, less contaminated injuries. Nevertheless, orthopaedic surgeons continue to debride and irrigate open joints regardless of the burden of contamination or size of arthrotomy.

Small Arthrotomies are Commonly Missed Injuries In an effort to identify and treat as many traumatic arthrotomies as possible, orthopaedic surgeons began looking for additional techniques to aid in their diagnosis. After it's introduction in 1975, saline arthrograms quickly became the gold standard for the diagnosis of small traumatic arthrotomies. This doctrine was called into question when they showed that saline load arthrograms, as they were commonly performed, had a sensitivity of only 43%. Two years later, it was recommended using 155-ml of saline to diagnose 95% of arthrotomies, a volume more than double what was previous used in clinical practice and not easily tolerated by most patients. Most recently, a study showed a false-negative rate of 67% when using 180-mL of saline for their arthrograms, a volume far beyond what would be tolerated in a conscious patient. Despite missing up to half of all small traumatic arthrotomies for the last 40 years, there has not been an outbreak in patients returning with septic arthritis from missed arthrotomies. The absence of such an occurrence raises the question if it is even necessary to formally debride and irrigate small traumatic arthrotomies in the operating room at a great cost to the patient.