The employee appeals the compensation judge’s finding on remand that the employee’s work-related right shoulder injury was not a substantial contributing cause of the employee’s decreased earning capacity from and after June 12, 2005, and from the corresponding denial of temporary partial disability benefits between June 12, 2005, and June 22, 2006.  We affirm.

The facts of this case are detailed in this court’s original decision remanding the matter to the compensation judge.  Westphall v. Honeywell, Inc., No. WC05-220 (W.C.C.A. Feb. 23, 2006).  In summary, on August 8, 2003, Deborah Westphall, the employee, sustained an admitted work-related injury to her right shoulder after she tripped and fell on her right shoulder while working as a technician for Honeywell, the self-insured employer.  At the time of her injury, the employee’s weekly wage was $1,583.36, which included 18 to 30 or 35 hours of overtime per week on a regular basis.

The employee was diagnosed with rotator cuff tear and underwent surgery on her right shoulder, which involved an arthroscopy with subacromial decompression, an open rotator cuff reconstruction and a bicep tenodesis, performed by Dr. Frank Norberg.  The employee was released to return to work in December 2003 with restrictions, at first working two hours per day.  On March 1, 2004, Dr. Norberg limited the employee to working seven hours per day.  By April 2004, she had worked her way up to 40 hours per week.  Dr. Norberg continued to assign work restrictions but did not specifically limit the number of hours she could work each week.  Overtime was available for the employee when she returned to full-time work, but she did not work over 40 hours per week because of her symptoms and her concerns about potential re-injury.  After the employee returned to work in December 2003, the employer paid temporary partial disability benefits based upon the difference in her weekly wage at the time of the injury and her reduced weekly wage.

The employee worked in a testing position which was repetitive in nature, and noted an increase in her right shoulder symptoms toward the end of each shift and the end of each week.  Starting on March 15, 2004, the employee worked a few days in a different work station which was more cramped than her other station.  The employee claimed that she sustained a left shoulder injury while working in this station.  The employee indicated that she had to hold a part more tightly in this station and that she began to experience symptoms in her left shoulder and arm, which she described as an aching on the top of her left shoulder and in the left biceps area.  The employee reported her left shoulder symptoms to Dr. Norberg at an examination on March 24, 2004.  Following a re-examination on May 5, 2004, Dr. Norberg assigned restrictions relating to both the employee’s right and left shoulders.

In August 2004, the employee transferred to a new position as an electrician technician.  The employee testified that this position caused increased pain in both shoulders.  She limited herself to 40 hours per week because of the increased pain in both shoulders.  Since the employee’s restrictions did not include a restriction on the number of hours worked, the employer asked her to discuss the limitation of hours, or the extent that she could work, with her treating physician.  In a report dated November 22, 2004, Dr. Norberg limited the employee to working 40 hours per week at least until after her right shoulder had healed from surgery and after she had undergone a functional capacities evaluation.

On December 14, 2004, the employee was evaluated by Dr. Michael D’Amato at the employer’s request.  Dr. D’Amato concluded that the employee’s left shoulder condition was unrelated to her work activities, determined that the employee had reached maximum medical improvement (MMI) from her right shoulder injury, and assigned a rating of 6% permanent partial disability to the body as a whole relative to her right shoulder.^[1]  Dr. D’Amato recommended permanent physical work restrictions for the employee’s right shoulder.  Following a later review of the employee’s job description, he expressed his opinion that the employee could work overtime hours performing the described work tasks.

On January 5, 2005, the employer filed a Notice of Intention to Discontinue Benefits (NOID), asserting that the employee was able to work overtime hours and no longer was entitled to payment of temporary partial disability benefits.  Dr. Norberg re-examined the employee on January 27, 2005, concluded that she had not yet reached maximum medical improvement, and again recommended that she work only 40 hours per week.  On January 28, 2005, an administrative conference was held to address the NOID.  In her order on discontinuance filed on February 7, 2005, a compensation judge determined that the employee’s treating physician had restricted her due to both her shoulders, and found that no reasonable grounds existed to discontinue the employee’s benefits.

On April 5, 2005, the employer filed a petition to discontinue the employee’s temporary partial disability benefits, alleging that her loss of earnings was not causally related to her August 8, 2003, right shoulder injury.  In its petition, the employer asserted that overtime hours were available to the employee, that her current job duties were light in nature and within her work restrictions, and that there was no medical reason that she could not return to her full pre-injury overtime hours.

In the meantime, on February 18, 2005, the employee filed a claim petition, listing two dates of injury: August 8, 2003, the date of her admitted injury to her right shoulder, and March 18, 2004, the date on which the employee claimed she had sustained a Gillette^[2] injury to her left shoulder.  In that claim petition, the employee sought permanent partial disability benefits, rehabilitation assistance, and surgery to her left shoulder.  The employer denied primary liability for the employee’s left shoulder injury.

On May 19, 2005, a hearing was held before a compensation judge to address the employer’s petition to discontinue temporary partial disability benefits.  The employee’s pending claim regarding her left shoulder injury was postponed and therefore was not addressed at this hearing.  In her findings and order served and filed June 20, 2005, the judge granted the petition to discontinue temporary partial disability benefits.  The employee appealed from the compensation judge’s finding that the employee’s reduced earning capacity was not causally related to her work injury to her right shoulder and from the discontinuance of her temporary partial disability benefits.

In July 2005, the employee underwent a functional capacities evaluation.  The physical therapist who performed the evaluation testified that the employee would be unable to work more than 40 hours per week based on a position that met the maximum abilities for the employee.  The physical therapist later testified that, in her opinion, the employee should not work over 40 hours per week based on the employee’s medical history of a surgically repaired torn rotator cuff and on the employee’s reports that her pain built as the work week progressed, and that “she needs time off to rest her shoulders and prevent further injury.”

On August 11, 2005, the employee filed another claim petition, seeking temporary partial disability benefits since April 5, 2005, due to her right shoulder injury.  On September 30, 2005, the employee filed a petition to vacate the June 20, 2005, findings and order, alleging newly discovered evidence based on the results of the functional capacities evaluation; the employer objected to the petition to vacate.  In an Order served and filed February 26, 2006, this court granted the employee’s petition to vacate, dismissed the appeal, and ordered that all pending claims be consolidated for hearing, on the bases that the admitted right shoulder condition and the denied left shoulder condition, which had not been litigated, were intertwined, that the functional capacity evaluation had been delayed due to the employee’s left shoulder condition, and that because both medical experts had recommended a functional capacity evaluation, the results of that evaluation should be considered by the compensation judge on remand.

A hearing was held on June 22, 2006, and a Findings and Order issued on August 23, 2006.  The compensation judge found that the employee’s work activities for the employer were not a substantial contributing factor in the employee’s left shoulder condition.  That finding was not appealed.  The judge also found that the employee’s work-related right shoulder injury was not a substantial contributing factor in her claimed wage loss, and denied the employee’s claim for temporary partial disability from August 8, 2003 through October 16, 2003, and from June 12, 2005 to the present and continuing.  The compensation judge also dismissed the April 5, 2005, petition to discontinue, which the employer had withdrawn.  The employee appeals from the denial of temporary partial disability benefits.^[3]

Temporary partial disability benefits are paid based on the difference between the weekly wage of the employee at the time of the injury and the wage the employee is able to earn in the employee’s partially disabled condition.  Minn. Stat. § 176.101, subd. 2.  To demonstrate entitlement to temporary partial disability benefits, an employee must show a work-related physical disability, an ability to work subject to the disability, and an actual loss of earning capacity that is causally related to the disability.  Krotzer v. Browning-Ferris/Woodlake Sanitation Serv., 459 N.W.2d 509, 43 W.C.D. 254 (Minn. 1990); Dorn v. A.J. Chromy Constr. Co., 310 Minn. 42, 245 N.W.2d 451, 29 W.C.D. 86 (1976).  The employee has the burden of establishing a diminution in earning capacity that is causally related to the disability.  Arouni v. Kelleher Constr., Inc., 426 N.W.2d 860, 864, 41 W.C.D. 42, 48-49 (Minn. 1988).  An employee’s post-injury wage is presumed to be representative of the employee’s reduced earning capacity.  Roberts v. Motor Cargo, Inc., 258 Minn. 425, 104 N.W.2d 546, 21 W.C.D. 314 (1960); Einberger v. 3M Co., 41 W.C.D. 727 (W.C.C.A. 1989).  In appropriate circumstances, this presumption can be rebutted with evidence indicating that the employee's ability to earn is different than the post-injury wage, Patterson v. Denny's Restaurant, 42 W.C.D. 868, 874 (W.C.C.A. 1989), and that presumption may also be rebutted by evidence establishing that the reduction in the employee’s earning capacity is unrelated to the employee’s disability.  Borchert v. American Spirits Graphics, 582 N.W.2d 214, 215, 58 W.C.D. 316, 318 (Minn. 1998).

In this case, the compensation judge found that the employee’s loss of earning capacity was not causally related to her work injury.  The issue of earning capacity is factual in nature and is determined by the compensation judge as the trier of fact.  Mathison v. Thermal Co., Inc., 308 Minn. 471, 243 N.W.2d 110, 28 W.C.D. 406 (1976); Noll v. Ceco Corp., 42 W.C.D. 553 (W.C.C.A. 1989); see Hanmer v. Wes Barrette Masonry, 403 N.W.2d 839, 39 W.C.D. 758 (Minn. 1987); see also Serra v. Hanna Mining Co., slip op. (W.C.C.A. Apr. 12, 2005), summarily aff’d (Minn. Aug. 23, 2005).  The question for this court on appeal is whether substantial evidence supports the decision of the compensation judge.

When an appeal is taken from a compensation judge’s factual findings, this court’s review on appeal is limited to a determination of whether the compensation judge's findings and order are "clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted."  Minn. Stat. § 176.421, subd. 1(3).  Where the judge’s factual determinations are adequately supported by substantial evidence, and not clearly erroneous, we must affirm.  Substantial evidence supports the findings if, in the context of the entire record, “they are supported by evidence that a reasonable mind might accept as adequate.”  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 59, 37 W.C.D. 235, 239 (Minn. 1984).  “Factfindings are clearly erroneous only if the reviewing court on the entire evidence is left with a definite and firm conviction that a mistake has been committed.”  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).  Findings of fact should not be disturbed, even though this court might disagree with them, “unless they are clearly erroneous in the sense that they are manifestly contrary to the weight of the evidence or not reasonably supported by the evidence as a whole.”  Id.

The employee argues that Dr. Norberg opined that the employee should only work 40 hours per week and that the physical therapist who conducted the functional capacities evaluation recommended that the employee should only work 40 hours per week.  Dr. Norberg testified in his deposition that any limitation on overtime hours was based on both the employee’s subjective complaints of pain as well as on her medical and surgical history.  Dr. D’Amato opined that, based upon the functional capacities evaluation, that there was nothing in the employee’s current job description that she could not do, and that the employee was capable of working overtime.  The compensation judge noted that the results of the functional capacities evaluation, which indicated that the employee should only work 40 hours per week, were based on the employee’s performance of various job duties not specifically involving those she performed with her current job.  The judge found the physical therapist’s opinion and limitation of hours to be unpersuasive.  It is the compensation judge's responsibility, as trier of fact, to resolve conflicts in expert testimony, Nord v. City of Cook, 360 N.W.2d 337, 342, 37 W.C.D. 364, 372 (Minn. 1985), and the compensation judge found Dr. D’Amato’s opinion to be the most persuasive of the medical opinions submitted into evidence.

The compensation judge noted that the employee was initially able to work overtime after her right shoulder injury.  At the first hearing, the employee testified that her work activities affected both shoulders, but that she hoped to work overtime in the future if her left shoulder condition resolved.  At the second hearing, she testified that the difficulty in both shoulders caused by vibrations at her current job was the reason she could not work overtime.  The compensation judge concluded that the employee’s testimony about, and her realization of, the work activity that limited her ability to work overtime was inconsistent with Dr. Norberg’s explanation of his basis for a 40-hour per week restriction.  The judge explained in her memorandum that Dr. Norberg did not consider the vibrating activity as a factor requiring a 40-hour per week restriction.  The judge concluded that the employee’s testimony concerning her symptoms was unreliable, and therefore rejected Dr. Norberg’s opinion since it was based, in part, on the employee’s reported symptoms.  It is the trier of fact's responsibility to assess the credibility of a witness, and a finding based on credibility of a witness will not be disturbed on appeal unless there is clear evidence to the contrary.  Tolzmann v. McCombs-Knutson Associates, 447 N.W.2d 196, 198, 42 W.C.D. 421, 424 (Minn. 1989) (citing Even v. Kraft, Inc., 445 N.W.2d 831, 835, 42 W.C.D. 220, 225 (Minn. 1989)).  It is not the role of this court to evaluate the credibility and probative value of witness testimony and to choose different inferences from the evidence than the compensation judge.  Krotzer v. Browning-Ferris/Woodlake Sanitation Serv., 459 N.W.2d 509, 513, 43 W.C.D. 254, 260-61 (Minn. 1990).

Substantial evidence, including medical records and expert medical opinion and testimony, supports the compensation judge’s finding that the employee’s work-related right shoulder injury was not a substantial contributing cause of the employee’s inability to work overtime hours and resulting decreased earning capacity.  Accordingly, we affirm.