When a veteran has a disability that affects both arms, both legs, or paired skeletal muscles, their overall combined rating must reflect what’s known as the bilateral factor. Specifically, the bilateral factor is defined by statute as existing when “a partial disability results from disease or injury of both arms, or of both legs, or of paired skeletal muscles, the ratings for the disabilities of the right and left sides will be combined as usual, and 10% of this value will be added before proceeding with further combinations.”
What is the reason behind the bilateral factor? The law recognizes that these situations are much more limiting on a veteran. If a veteran has a disability affecting his right arm, and then his left arm becomes disabled, he is severely limited in his ability to function. A veteran with a disability affecting only his left arm has his right arm to use for daily tasks. However, a veteran with a disability in both arms is able to do far less. The bilateral factor’s purpose is to compensate a veteran for the additional loss of their ability to function as a result of both sides of their body being affected.
It is important to note that a veteran does not have to have the same disability on both sides in order for the bilateral factor to apply. VA disability ratings look at whether an upper extremity (such as the arm), or a lower extremity (such as the leg) are affected by a disability. The bilateral factor will apply as long as the veteran has disabilities affecting the left and right upper extremities or the left and right lower extremities. For example, the bilateral factor will still apply if a veteran has a right knee condition and a left hip condition because there is a disability affecting the right lower extremity and a disability affecting the left lower extremity. However, the bilateral factor would NOT apply if a veteran has a right shoulder condition and left knee condition.
VA math is a complicated process, and throwing the bilateral factor into the mix can further complicate things. The 10% rating associated with the bilateral factor isn’t treated as though the veteran has another condition rated at 10%. Instead, the 10% is applied to the veteran’s combined rating for their service-connected disabilities, with the resulting number added to the combined rating. Let’s look at this step by step with an example. A veteran with a right foot condition and a left foot condition has a combined rating of 60%. In this example, the veteran would have a bilateral factor of 6% (60% multiplied by 10%). This 6% is then added to the 60% for an overall combined rating of 66%. The 66% is then rounded up to 70%. This example shows how powerful the bilateral rating can be. With the bilateral factor applied, the veteran now meets the schedular rating requirements for individual unemployability.
The math gets even more complicated when a veteran has service-connected conditions that are bilateral in addition to service-connected disabilities that aren’t bilateral. When a veteran has bilateral service conditions (for example, a left foot condition and a right knee condition) and also has service conditions that aren’t bilateral (for example, a back condition) the bilateral factor is calculated based on the combined rating of the bilateral conditions only. Once the bilateral factor is calculated it is added to the combined rating of the bilateral conditions. The resulting number is then combined with the non-bilateral condition to get the veteran’s final combined rating. Let’s break this down step by step by looking at another example Now, let’s say the veteran has a back condition (rated at 40%), a right foot condition (rated at 20%) and left knee condition (rated at 10%). The following steps illustrate how this veteran’s final combined rating will be calculated taking the bilateral factor into account:
- The combined rating of the veteran’s bilateral conditions (right foot and left knee) is 28%. For more information on how to calculate this number click here.
- To get the bilateral factor we take 28% and multiply it by 10%. This gives the veteran a bilateral factor of 2.8%.
- We take the 2.8% and add it to the combined rating of the veteran’s bilateral conditions (2.8% + 28%). This gives us a combined rating of 31% for the veteran’s bilateral conditions. The 31% is the result of rounding 30.8% to the nearest whole number.
- To get the veteran’s final combined rating we combine the 31% with the veteran’s back condition rated at 40%. This gives us 58.6, or 60%.
Overall, the bilateral factor has the effect of increasing a veteran’s combined rating. The steps are complicated, but the reasoning is simple: veteran’s with bilateral conditions are severely limited in their ability to function. Luckily, the math behind bilateral factors and combined ratings can be done easily by using our disability calculator. By typing in the percentages and extremities affected, the disability calculator automatically applies the bilateral factor when applicable.