Medical causation
Section 287.020.3(1) RSMo sets forth the standard for medical causation applicable to this claim and provides, in relevant part, as follows:
An injury by accident is compensable only if the accident was the prevailing factor in causing both the resulting medical condition and disability. "The prevailing factor" is defined to be the primary factor, in relation to any other factor, causing both the resulting medical condition and disability.
In her award, the administrative law judge expressly credited the opinion from employer's expert, Dr. Michael Chabot, with respect to the issue of medical causation. Yet, implicit in the administrative law judge's award of permanent partial disability benefits is a rejection of the ultimate opinion from Dr. Chabot that employee suffered a mere lumbar strain that did not result in any permanent disability. We agree with the administrative law judge's (implied) finding that Dr. Chabot's ultimate opinion is not persuasive.
Much has been made of employee's statements in July 2011 to the treating physician Dr. Laurie Womack. Employer urges that because employee downplayed his low back symptoms to Dr. Womack, he is a "liar" who is not deserving of workers' compensation benefits. We are not persuaded. Employee's expert, Dr. Robert Poetz, persuasively testified that symptoms from a herniated disc vary widely and can wax and wane in severity. As of the July 1, 2011, visit with Dr. Womack, employee had been restricted from heavy lifting at work for over a week, and had been taking muscle relaxers to treat his pain complaints. Especially in this context, we cannot adopt employer's rather hyperbolic characterization of employee as someone "unwilling to speak the truth." Rather, as employee forthrightly admits, he minimized his symptoms when he saw Dr. Womack in July 2011 because he was eager to get back to work in order to provide for his family. We find that employee wanted to get back to work and simply overestimated his ability to return to his normal daily work duties of continually lifting 100 pound bags of sugar. In our view, the fact that employee was ultimately unable to do so without further medical treatment is persuasive evidence that employee suffered more than the mere lumbar strain identified by Dr. Chabot.
In any event, where the issue of medical causation turns on the question whether the accident caused employee to suffer complex internal pathology affecting the discs in his lumbar spine, we do not view employee's lay testimony as dispositive of the issue of medical causation. Rather, our analysis turns on weighing the persuasive value of the competing expert medical opinions. After careful consideration, we are more persuaded by the opinions from Dr. Poetz.
As noted by the administrative law judge, Dr. Poetz explained that employee's symptoms, which included the sudden onset of severe low back and radiating left leg pain, indicate that he suffered traumatic disc herniations in his lumbar spine, as opposed to herniations resulting from degenerative changes, which would not be consistent with the sudden onset of symptoms employee experienced. We find this testimony from Dr. Poetz persuasive. Notably, Dr. Chabot testified that "everything that's noted other than the disk changes at
L5-S1 are chronic and degenerative." Transcript, page 996 (emphasis added). In light of this tacit concession from Dr. Chabot, it appears to us that the uncontradicted evidence in this case compels a finding that, at the very least, the accident of June 21, 2011, caused employee to suffer a herniated L5-S1 disc in his lumbar spine.
Employer argues that the MRI taken on October 24, 2011, shows an objective change in pathology contrasted with the earlier MRI of August 22, 2011, because one radiologist, Dr. John Markle, described "herniations" at L3-4 and L4-5 in October where another, Dr. Gaspar Fernandez, described "bulges" at the same levels in August. But employer did not solicit an opinion from Dr. Chabot or Dr. Womack in this regard, and does not direct us to any other expert medical testimony that would support a finding that the October MRI shows an objective change in pathology. Absent such evidence, we are not persuaded to make a finding that the October MRI reflects a clear change in pathology, as there are many possible reasons (e.g. differences in the quality of the study, differences in training, differences in terminology) why one radiologist might describe an MRI study differently from another.
Importantly, all three physicians deposed in this case, Drs. Womack, Chabot, and Poetz, agree there is no record that employee was having any symptoms in his back or left leg leading up to the accident of June 21, 2011. In our view, Dr. Poetz's opinions more persuasively track employee's history of immediate radicular symptoms following the accident, contrasted with Dr. Chabot's assumption that all of employee's current low back problems must be the product of preexisting conditions that were asymptomatic prior to June 2011. As noted above, where employee had the benefit of light duty and prescription muscle relaxers to manage his symptoms, and was minimizing the severity of his symptoms because of an understandable desire to get back to work, we do not read the July 2011 Dr. Womack treatment notes as persuasively establishing employee's work injury as resolved at that time. Nor do we find evidence of any intervening injury or other event to explain employee's need for additional treatment after he returned to lifting 100 pound bags for employer. Rather, it is quite clear to us that employee's symptoms referable to the work injury worsened in August 2011 because his low back injury was more serious than he thought, and would not permit him to return to such heavy duty work absent additional treatment.
Accordingly, we adopt Dr. Poetz's causation opinion and find that the accident of June 21, 2011, was the prevailing factor causing employee to suffer the resulting medical conditions of lumbar disc herniations at L3-4, L4-5, and L5-S1, exacerbation of employee's preexisting degenerative disc disease, and attendant disability. Dr. Poetz rated employee's permanent partial disability referable to the accident at 45 % of the body as a whole. As noted above, Dr. Chabot did not provide a competing permanent partial disability rating. Employee credibly endorses complaints of continuing severe low back pain, for which he daily takes the prescription pain medications morphine, Tramadol, Hydrocodone, and the muscle relaxer Tizanidine. When he is not at work, employee spends his time lying down, and he needs his wife's help to get dressed. Although employee continues to work for employer, it is in a substantially accommodated fashion. In light of this evidence, we find that employee suffered a 40 % permanent partial disability of the body as a whole as a result of the accident.