This month is the 20th anniversary of the MESS score, a system that helps predict salvageability of mangled extremities (Mangled Extremity Scoring System). Obviously, the acronym was chosen to help describe the clinical problem.
The system was originated at the Harborview Medical Center in Seattle. The development was not very scientific; the authors put their heads together and made a list of the four things that they observed predicted limb salvage:
- Degree of skeletal and soft tissue injury
- Presence of limb ischemia
- Presence of shock
The system was used retrospectively in a group of 25 patients(!) and the authors found a nice breakpoint at 7. Any mangled extremities with a MESS of 7 or more required amputation. They then applied this to 26 patients prospectively(!) and got the same result.
As you can see, the numbers were small, and there was no followup information. Nevertheless, MESS still stands today, and the critical MESS score has not changed much. It has been validated by a number of other studies during the past 20 years. It is conceivable that the critical score will slowly creep upward with advancements in flap coverage and surgical technique, but it hasn’t done so yet.
Reference: Objective Criteria Accurately Predict Amputation Following Lower Extremity Trauma. Johansen, et al. J Trauma 30(5): 568, 1990.
Centers that take care of blunt trauma are familiar with the spectrum on injury that is directly attributable to seat belt use. Although proper restraint significantly decreases mortality and serious head injury, seat belts can cause visceral injury, especially to small bowel.
Lap belt use has been associated with Chance fracture (flexion distraction injury to the lumbar spine) since 1982. The association between seat belts and intra-abdominal injury, especially with an obvious “seat belt sign” was first described in 1987.
Twenty years ago, orthopedic surgeons in Manitoba finally put two and two together and reported a series of 7 cases of Chance fractures. They noted that 6 of the fractures were associated with restraint use. Seat belt sign was also present in 5 of the 6 patients with fractures and three of the six had bowel injuries.
The authors noted that many provinces were mandating seatbelt use at the time, and they predicted that the number of Chance fractures, seat belt signs and hollow viscus injuries would increase. On the positive side, the number of deaths and serious head injuries would be expected to decline.
Although this was a small series, it finally cemented the unusual Chance fracture, seat belt sign, and bowel injury after motor vehicle trauma.
Reference: Pediatric Chance Fractures: Association with Intra-abdominal Injuries and Seatbelt Use. Reid et al. J Trauma 30(4) 384-91, 1990.
Through the 1970’s and 80’s, a colon injury was automatically managed by repair/resection coupled with a diverting colostomy. This technique became commonplace due to bad experiences with repair attempts during earlier decades.
During the late 70’s, a few trauma centers began dabbling in primary repair. At Wayne State University in Detroit, John Kirkpatrick had popularized an exteriorization technique. This involved repairing the colon and bringing the area of repair to the outside of the body. The area was watched for several days and if no breakdown was noted, it could be dropped back into the abdomen with a relatively minor procedure.
After the success of exteriorization, some of the surgeons at Receiving began repairing colon injuries and leaving them in the abdomen. They retrospectively looked at their experience with this radical idea from 1980 to 1987. Injuries were predominantly penetrating. From 1980 to 1983, 29% of patients were managed in this way. During the final years, the use of this technique increased to 56%.
Interestingly, Injury Severity Score in patients who did not get colostomy was higher, but the number of complications (leaks, intra-abdominal abscesses) was lower! Colostomy patients had 15 abscesses, while those without colostomy had 1 leak and only 5 abscesses.
This paper represents one of the first reports on colon injury management without colostomy, and set the stage for additional trials. It has led to the nearly routine use of this technique in current times.
Reference: Management of the Injured Colon: Evolving Practice at an Urban Trauma Center. Levison, Thomas, Wiencek and Wilson. J Trauma 30(3): 247-253, 1980.
We take for granted that the so-called seatbelt sign is a harbinger of bad things in the abdomen. One of the first papers on this topic appeared in the February 1990 issue of the Journal of Trauma, entitled “Intra-abdominal Seatbelt Injury.”
The paper presents 8 cases who presented to the ED with a seatbelt sign after a motor vehicle crash. They found that serious injuries to the bowel and mesentery might be present without early symptoms or physical signs, and that CT scan and peritoneal lavage were not fully reliable in finding the injuries. Their conclusion was that the always wise “high index of suspicion” should be used in these patients.
Current day thinking has not changed much. During the last two decades, sentiment has swung from always operating based on these finding to being more selective. We recommend using good judgment. Seatbelt sign should always arouse a healthy suspicion for injury. A CT scan is now mandatory. If anything unusual is found (free fluid, bowel wall or mesenteric thickening or stranding) then a trip to the OR is indicated. Small bowel injuries may not become symptomatic for 12-72 hours, increasing the eventual complication rate if treatment is delayed.
It’s always interesting to review the trauma literature of days gone by to see where we’ve been and how it impacts where we are today in trauma care. Here are a few articles from the Jan 1990 Journal of Trauma (Volume 30 Number 1) worth commenting on:
Efficacy of Liver Wound Healing by Secondary Intent. Dulchavsky et al, page 44-48. This paper compared wound healing using tensile strength in pigs and dogs. The authors compared primary operative closure, closure with an omental buttress, and healing by secondary intention. They found that the strength of secondary healing equaled or exceeded that in both types of operative repair by 6 weeks post-injury. This paper and several similar ones laid the groundwork for our understanding of solid organ healing and lend weight to the somewhat arbitrary guidelines of resuming full physical activity after 6 weeks.
Intestinal Injuries Missed by Computed Tomography. Sherck et al, page 1-7. The authors retrospectively looked at 10 CT scans done over a 9 year period that were done in patients who eventually were found to have an intestinal injury. The injury became apparent in 2 hours to 3 days after the traumatic event. Even when the authors knew that a bowel injury was present, they could definitively diagnose the problem on the initial CT in only 2. The authors concluded that CT could not reliably detect these injuries. Little has changed since this paper was published, even though the scan technology has improved greatly (1 or 2 slice scanners in 1990, 16-64 slices now). We have gotten better at detecting bowel injury with better resolutions, but the diagnosis still remains a clinical one.
Techniques of Splenic Preservation Using Fibrin Glue. Shoemaker et al, page 97-101. The senior author first described the use of fibrin glue in splenic injury in 1983, and continued to investigate it over the next 7 years. This paper was the largest human series at the time. The authors found that it limited blood loss and transfusions, although there was no actual control group. They found that it increased splenic salvage rates to 86% in operative cases, and repeat CT did not show rebleeding or abscess formation. This study added a new technique to the trauma surgeon’s armamentarium in dealing with solid organ injury. Although later studies did find a modest increase in abscess formation, the technique remains a viable alternative when operatively managing solid organ injury. Overall, it is not used as much now because nonoperative management has become quite refined, with a success rate of about 93%.