This is the second appeal in this case. The employee was involved in a motor vehicle accident while operating a truck within the course and scope of her employment. As a result of medical evaluations following the accident, the employee was diagnosed with severe “end stage” tricompartmental osteoarthritis in both knees. The authorized treating physician selected from an employer-provided panel opined that, although the truck accident exacerbated the employee’s pre-existing condition, the primary need for total knee replacements was the underlying osteoarthritis, not the work accident. Another physician who evaluated the employee concluded that the truck accident made the employee’s previously asymptomatic condition symptomatic, and the resulting symptoms primarily caused the need for total knee replacements. Following an expedited hearing, the trial court ordered the employer to: (1) pay past medical expenses related to the left total knee replacement; (2) authorize the right total knee replacement; (3) authorize the physician the employee had selected to perform her surgery for her medical care moving forward; and (4) pay temporary total disability benefits and mileage expenses. That order was appealed, and we affirmed the trial court’s determination that the employee was likely to prevail at trial in proving she suffered a compensable aggravation of her pre-existing condition primarily caused by the truck accident. However, we reversed the trial court’s conclusion that the employee was likely to prevail in proving that the truck accident was the primary cause of her need for bilateral total knee replacements. Thereafter, the parties obtained additional proof and submitted additional evidence at a compensation hearing, after which the trial court issued a compensation order: (1) awarding the employee medical expenses related to her left total knee replacement; (2) ordering the employer to authorize all reasonable and necessary future medical benefits, including a right total knee replacement; (3) ordering the employer to authorize the employee’s physician to provide future medical treatment; and (4) awarding total disability benefits, permanent total disability benefits, and discretionary costs. The employer has appealed. Upon careful consideration of the record and arguments of counsel, we affirm in part, reverse in part, and certify as final the trial court’s order as modified.