Medical Exhibits - Demonstrative Evidence Expert Blog - MediVisuals

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations,MediVisuals Incorporated

Long before science had advanced to allow imaging of the body in sectional views by computed tomography (CT) and magnetic resonance imaging (MRI), medical illustrators were illustrating the body in sectional views because these views are the best way to appreciate some anatomical relationships. 

Medical illustrators, physicians, and others who have studied anatomy are familiar with sectional views of the body and appreciate the value of these views in explaining the relationship of anatomical structures. However, accomplished and well respected jury consultants and non-medical illustrator legal graphics experts have expressed concerns that sectional views may be difficult for some jury members to understand. These individuals' opinions are valuable to those of us in the legal graphics business, and I agree with their opinions that, when other views can communicate a particular relationship message equally as well or better, sectional views should be avoided. I also believe most of these experts will agree that there are times and places in which sectional views of anatomy are the best way to appreciate some anatomical relationships. Granted, there have been times when we have been working on specific cases and experts have insisted that sectional views be absolutely and unconditionally avoided. Unfortunately, in these situations the experts were unable to suggest a more effective view to communicate the relevant anatomical relationships (at least in a way that was practical in terms of time and expense). That being the case, sometimes the sectional views were used despite the input of the experts, and at other times, the relationships of the structures had to be explained without the benefits of graphics.

A way to perhaps explain how sectional views help decision makers appreciate relevant anatomical and pathological relationships is to compare them to aerial views or photographs of the scene of a collision.  Space is defined in three planes. Only two of these planes can effectively be demonstrated in a two-dimensional rendering. For example, aerial views have long been used to help explain the positions of vehicles and structures that simply can't be appreciate from "street views". When viewing the scene of a collision from a "street view", one can appreciate vertical and horizontal distances, but not depth; distances close to and far from the viewer's perspective are very difficult to appreciate (see the below figures). By comparison, when viewing an operative site through a "surgeon's view", vertical and horizontal distances can be appreciated, but the depth of the incision and the relationships of the various structures within and around the incision are very difficult or impossible to appreciate.

The "aerial view" of the collision scene allows the viewer to appreciate distances in two geographical planes as well (distances right and left, and toward and away from the "street view," but the ability to appreciate up and down is lost). Also, the locations of relevant structures or vehicles that may have been obstructed by nearby structures (such as buildings trees, signs, or other vehicles) can now be appreciated. Similarly, a sectional view of anatomy can help decision makers appreciate depth relationships of structures. Or, a sectional view of a step in a surgical illustration can allow the viewer to appreciate the depth of the surgery as well as the additional structures that may have been injured (or at risk of injury) during the invasive procedure.  These specific depth  relationships could not be appreciated from the "surgeon's view" of the same surgery shown in the above illustration.

Exhibits developed to help explain the invasive nature of a surgery and the disruption of the soft tissues during operative procedures are critical. For that reason, sectional views are critical in aiding a testifying physician to explain these issues. For example, the exhibit panel that demonstrates an anterior cervical discectomy and fusion (ACDF) that does not include a cross-section through the neck fails to emphasize the depth of the incision and disruption of tissues (essentially all the way to the center of the neck). This depth simply cannot be appreciated in a "surgeon's view".

In order to appreciate cross-sections, orientation views that show the level and direction of the section are helpful (see below), or when time, budget, and presentation format (digital as opposed to a physical panel) allow, a short animation showing the sectional view actually coming out of the orientation view such as MediVisuals' "Scan Selector^TM" can be used.

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations, MediVisuals Incorporated

Individuals who develop new or suddenly worsening symptoms consistent with nerve root or spinal cord impingement following a traumatic event are sometimes diagnosed with “disc-osteophyte complexes”. The term “disc-osteophyte complex” generally refers to abnormal extension of intervertebral disc material that accompanies immediately adjacent osteophyte formation at the vertebral body margin (see the below figure). It is important to note (as shown in the illustrations) that the disc almost always extends further than the osteophytes into the neural foramen or spinal canal to irritate or impinge upon nerve roots or the spinal cord.

Occasionally, individuals who are evaluated shortly after a traumatic event are found to have disc-osteophyte complexes. Because a minimum of several weeks is required for osteophytes to form as a result of a traumatic event, defendant insurance companies may argue that the presence of osteophytes so soon after the traumatic event in question may prove that the plaintiff’s injuries preexisted the traumatic event. Since it is the disc pathology extending beyond the osteophytes that is the actual cause of the nerve root or spinal cord irritation and inflammation, the defense’s arguments are not valid. As shown in the illustrations below, the sequence of events that typically takes place in these cases is that the plaintiff had minimally symptomatic or asymptomatic disc osteophytes prior to the traumatic event in question. During the traumatic event, the disc sustains trauma that results in worsening of the disc pathology while the osteophyte portion of the osteophyte/disc complex remains essentially unchanged. This worsening of the disc pathology in turn results in new or increased irritation or impingement of the neural elements.

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations, MediVisuals Incorporated

The surgical trauma that a plaintiff has to undergo after the initial bodily injuries following a traumatic event are always major points of emphasis when arguing damages in a personal injury case.  This is certainly the situation with cases that involve broken bones that require invasive surgical procedures to realign broken bone fragments ("reduce") and secure ("fixate") the bones with hardware to keep them properly aligned during healing.  Too often, however, the emphasis is solely on the effects on the bones from these "Open Reduction and Internal Fixation" (ORIF) procedures, and very little emphasis is placed on the surgical disruption of the soft tissues that takes place during these procedures.

In a case involving ORIF of a distal fibula (a.k.a. lateral malleolus) fracture, in order to emphasize the surgical trauma endured by a plaintiff, an attorney may have a visual prepared of a postoperative X-ray.  The visual may consist of only a postoperative X-ray or a print of the X-ray with a corresponding illustration (see the below figure). 

The above images are certainly helpful, but fail to address the intra-operative trauma to the soft tissues that is required to gain access to the bone fragments.  For that purpose, intra-operative illustrations that truthfully depict the soft tissue disruption should be considered (see the below figure) or even an animation showing the procedures such as the one at this link: http://www.medivisuals.com/fibularplatingORIF.aspx

Illustrations or animations that at least touch on the soft tissue disruption allow testifying physicians the opportunity to explain the many tissues traumatized during the procedure and allow insurance adjustors, mediators, and jurors an opportunity to take these additional injuries into consideration when determining the severity of a plaintiff's entire injuries.

Many attorneys considering realistic illustrations such as the one above, express a concern that judges may not allow the images to be used because they are too "graphic" or "inflammatory".  Certainly, counsel should make themselves aware and consider the preferences of certain jurisdictions and specific judges before determining whether an illustration should be developed that realistically depicts injuries or whether diagrammatic (cartoon-like) illustrations should be developed instead.  There are a number of very good arguments to support the use of "realistic" illustrations over "cartoons".  Those arguments as well as other discussions regarding illustration styles will be addressed in future blogs.

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations, MediVisuals Incorporated

Intra-articular fractures are simply fractures that involve a joint space (see below figure). While intra-articular fractures appear very similar to those that do not involve a joint space (extra-articular fractures), intra-articular fractures are significantly more serious because they are associated with a much greater incidence of long-term complications.

In order to appreciate why intra-articular fractures can be so problematic, a fundamental understanding of a typical joint is helpful. The following images show a knee joint. With the exception of a meniscus, almost all moveable joints are similar to the knee joint in that the joints are lined with a thick, shock-absorbing articular cartilage adherent to smooth, bony surfaces that allow pain-free movement.




When a fracture involves the articular surface of one or more bones of a joint, the articular cartilage and smooth articular surface of the bone are disrupted. In order for joints to have the best chance of proper joint function after healing, physicians go to greater effort to make sure the bony surfaces are properly aligned and that the joint is properly immobilized than they would with a similar fracture that is extra-articular. Even with the best fracture alignment and joint immobilization, subtle disturbances in the joint surface and the natural bone reformation that take place during healing can result in uneven joint surfaces and injury to the overlying articular cartilage (see the below illustration). Because of the abnormalities of the injured and healed joint surface, natural movement of the joint can also damage the articular cartilage of the opposing joint surface. Over the course of time, these injuries self-perpetuate and may necessitate arthroscopic debridement, chondroplasty or even joint replacement.

It is also important to realize that a fracture needs not enter a joint to result in injury to the articular surfaces and begin the self-perpetuating post-traumatic breakdown of the joint surfaces (post-traumatic arthritis). As shown in the below illustrations, joint trauma without a diagnosable fracture of any type can injure the smooth, shock-absorbing articular cartilage, with or without microfractures of the underlying bone. This can result in partial or total loss of the articular cartilage and in uneven "bone-on-bone" articulation that severely decrease range of motion and result in debilitating joint pain.

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations, MediVisuals Incorporated

A traumatic event causing injury to an intervertebral disc may also cause subtle injuries to the bones around the disc. During an extreme lateral flexion injury (shown in the image below), the edges of the bone are driven together, injuring both the disc and the bone. As the bone/disc junction heals, overgrowths referred to as osteophytes may form.

Osteophytes take weeks or months to develop following a traumatic event; therefore, any osteophytes that are present soon after a traumatic event are likely pre-existing.

The osteophytes themselves may compress the neural elements as in the illustration above; however, in most situations, the osteophytes are a part of an OSTEOPHYTE/DISC COMPLEX. This is when the osteophytes and disc extend beyond their normal limits and compress the neural elements (spinal cord, nerve roots). In cases where osteophytes may have pre-existed a traumatic event, worsening of the disc bulge could occur following the trauma, resulting in new or aggravated symptoms.

Sometimes disc and ligament injuries occur on the same side as the force of impact. Other times, they occur on the opposite side. Injuries to the disc on the same side as the force are the result of stretching and tearing forces. On the opposite side, compression forces result in tears and micro fractures of the tissues and bones. (see illustration below). Osteophytes and facet hypertrophy can also form following injuries to intervertebral discs and ligaments. Injuries to the discs and ligaments result in instability and excessive motion of the joints that, in turn, results in constant trauma to the bone/disc and ligament junctions. This ongoing trauma results in overgrowth of the bones as it continually cycles through episodes of healing and reinjury.