The employee appeals the compensation judge’s findings that the employee failed to prove that he sustained a work-related injury to his low back on October 13, 2008, and that he did not conduct an adequate job search.  We affirm in part, vacate in part, and remand.

Richard Drury, the employee, worked as a driver/dock worker for YRC International (formerly known as Roadway Express), the self-insured employer, on October 13, 2008.  He worked a fifteen hour day, loading, delivering, and picking up freight on his route.  The employee testified that at one stop, he used an electric pallet jack that was broken and was difficult to pull.  The employee also testified that he awoke very early the next morning with severe low back and leg pain and that he called in to report he was unable to work and had been injured while working the day before.

On October 14, 2008, the employee was treated at the St. Croix Regional Medical Center emergency room for low back pain radiating to his legs.^[1]  He reported that the pain was related to his work activities, including using a jack to lift and move freight, the day before.  A lumbar spine x-ray taken that day indicated slight anterolisthesis at L3 and L4, but no spondylolysis or fractures.  The employee was released to work with light duty restrictions, but the employer did not have light duty work available.  The employer initially terminated the employee’s position for calling in late on October 14 to report that he was unable to work.  The parties agreed, after a grievance proceeding, that the employee could return to work for the employer once he was released for work without restrictions.

The employee had undergone prior treatment for low back pain.  In January 1997, he sought treatment at the Apple Valley Medical Center for low back pain; x-rays indicated minimal spondylotic and osteoarthritic changes to the lumber spine.  In March 2000, the employee was treated for left-sided low back pain after a work-related lifting incident.  The employee again sought treatment in January 2006 at the Apple Valley Medical Center for right-sided mid-back and low back pain, which he reported was work-related.  X-rays taken at that time indicated minimal anterior osteophytes at L4 and L5 levels and minimal loss of disc height at L3 and L5 levels.  On May 28, 2008, the employee treated at the St. Croix Regional Medical Center for left leg pain, which he reported had been occurring intermittently for two weeks.  He did not report a cause of these symptoms.  The employee also underwent five chiropractic treatments at Holmquist Advanced Chiropractic in June 2008.

After his October 2008 injury, the employee continued his treatment with Dr. Thomas Hinck at the St. Croix Medical Center.  During an office visit on October 21, 2008, the employee reported that he had been “driving and pulling pallets with pallet jack for 15 hours on the day of injury.”  During a physical therapy evaluation on October 28, 2008, he indicated that he had pulled a “heavier-than-usual pallet” on the day of injury.  A January 2009 MRI scan indicated anterolithesis with facet arthropathy and a disc protrusion at L3-4 causing significant bilateral lateral recess encroachment affecting the L4 nerve roots, a shallow disc protrusion at L4-5 with facet arthropathy, facet arthropathy at L2-3 and shallow right-sided disc protrusion at L5-S1.

The employee filled out the employer’s injury report, dated November 4, 2008, which indicated that he was injured when he was “pulling pallet jacks and pushing pallet jacks and at one of my stops [with an] elec[tric] pallet jack the reverse on the pallet jack did not work and I pulled the elec[tric] pallet jack out from underneath the freight.”  The employer denied primary liability for the employee’s injury.

The employee filed a claim petition for temporary partial disability benefits, permanent partial disability benefits, medical expenses, and a vocational rehabilitation consultation.  The self-insured employer admitted that the employee’s medical treatment was reasonable and necessary, but denied that the employee’s injury was causally related to his work, or alternatively claimed that any injury was temporary and had resolved without any permanent partial disability.

On April 6, 2009, the employee was evaluated by Dr. Joseph Teynor at the employer’s request.  Dr. Teynor opined that the employee had not sustained a work injury on October 13, 2008, but that he had pre-existing chronic lumbar stenosis.  The employee’s treating physician, Dr. Hinck, opined in a report dated October 21, 2009, that the employee’s pre-existing back symptoms were exacerbated by his work activity.

A hearing was held on October 29, 2009.  The compensation judge found that the employee had failed to prove that he had sustained a work-related injury on October 13, 2008.  He noted that the degenerative changes shown on the employee’s January 2009 MRI scan had existed prior to his October 2008 injury.  He also noted that the employee had experienced low back symptoms in the past, similar to those he described since the October 2008 incident, most notably only five months prior to October 2008.  The compensation judge also found that although the employee had been medically released to light duty work, including driving, since October 2008, and although the employer had no available work until the employee was released without restrictions, the employee had not conducted a diligent job search for a light-duty position.  The employee appeals.

On appeal, the Workers' Compensation Court of Appeals must determine whether “the findings of fact and order [are] clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.”  Minn. Stat. § 176.421, subd. 1.  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).  Where evidence conflicts or more than one inference may reasonably be drawn from the evidence, the findings are to be affirmed.  Id. at 60, 37 W.C.D. at 240.  Similarly, findings of fact should not be disturbed, even though the reviewing 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.”  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).

Drs. Teynor and Hinck provided opposing opinions on the issue of whether the employee sustained an injury on October 13, 2008, as a result of his work.  The compensation judge specifically rejected Dr. Teynor’s opinion, stating that his comments in his reports suggested “a bias which raises significant doubt as to the foundation and medical support for his causation opinion.”  The employee claims that the compensation judge erred by not relying upon Dr. Hinck’s opinion, arguing that his opinion had adequate foundation.  Dr. Hinck opined that the employee’s pre-existing condition was exacerbated by his work activity.  Foundation goes to the competency of a witness to provide an expert opinion.  The competency of a medical expert depends both on the witness’s scientific knowledge and the witness’s practical experience with the subject matter of the offered testimony.  Drews v. Kohl’s, 55 W.C.D. 33 (W.C.C.A.1996) (citing Reinhardt v. Colton, 337 N.W.2d 88, 93 (Minn. 1983)).  Sufficient knowledge of the subject matter may be obtained by personal knowledge and experience, review of medical records, a hypothetical question or testimony at the hearing.  Scott v. Southview Chevrolet Co., 267 N.W.2d 185, 30 W.C.D. 426 (Minn. 1978).  Dr. Hinck was the employee’s treating physician; he took the employee’s history and examined him.  This level of knowledge and experience is sufficient to provide adequate foundation for the opinion of a medical expert, and Dr. Hinck’s opinion was adequately founded.  See Grunst v. Immanuel-St. Joseph’s Hosp., 424 N.W.2d 66, 40 W.C.D. 1130 (Minn. 1988).  While Dr. Hinck’s opinion had adequate foundation, however, the compensation judge was not required to rely on that opinion.

The judge dismissed Dr. Hinck’s opinion because the doctor did not discuss the employee’s previous treatment for similar low back symptoms or explain how the current need for treatment was different from the previous treatment.  We note that an expert medical opinion also does not lack foundation because the doctor fails to explain the mechanism of injury or the underlying reasons for his opinion, but that the presence or absence of such testimony goes to the weight that may be afforded the opinion by the compensation judge.  All that is required, under the facts of the case when considered as a whole, is that a competent medical witness opined that the injury causally contributed to the disabling condition.  See, e.g., Goss v. Ford Motor Co., 55 W.C.D. 316 (W.C.C.A. 1996); Darnick v. Swett & Crawford, slip op. (W.C.C.A. Oct. 29, 2002).  In this case, the compensation judge chose not to rely on Dr. Hinck’s medical opinion based on his inferences regarding the circumstances of the employee’s reporting of the injury in his medical records.

In denying the employee’s claim, the compensation judge specifically emphasized that the employee had not attributed his symptoms to pulling an electric pallet jack until three weeks after the injury, when he filled out the employer’s injury report, even though the compensation judge also noted that on October 28, 2008, the employee reported that he had pulled a “heavier-than-usual pallet” on the day of injury.  The judge ignored the medical records which indicated that on October 14, 2008, while at the emergency room, the employee had mentioned using a jack during his work activities the day before, and had also reported that he had been “driving and pulling pallets with pallet jack for 15 hours on the day of injury” when he was treated on October 21, 2008.

We note that generally “[w]here more than one inference may reasonably be drawn from the evidence,” the compensation judge's findings are upheld.  Nord v. City of Cook, 360 N.W.2d 337, 342, 37 W.C.D. 364, 371 (Minn. 1985).  In this case, the compensation judge stated that the employee “first attributed his symptoms to pulling the electric pallet jack at Division Stamping when he filled out an injury report for the employer on [November 4, 2008].”  (Memo. at 5.)  Since the compensation judge chose not to accept either of the medical opinions submitted by the parties, the judge’s inference regarding the employee’s medical records is more determinative than in the usual case.  While the injury report may be the first time that the record indicates the employee’s explanation of his injury in detail, it is not the first time that the employee referred to the use of a pallet jack in regard to his injury, as the judge’s statement implies.  The medical records do not contradict the employee’s testimony regarding his injury, and there was no other witness to the injury.  Under the circumstances of this case, we conclude that substantial evidence does not support the judge’s finding that the employee failed to prove that he sustained a work-related injury to his low back on October 13, 2008.  We therefore vacate this finding and the denial of the employee’s claims, and remand for reconsideration of the causation issue.

The employee also appeals the compensation judge’s finding that the employee did not conduct an adequate job search.  The employer did not have light-duty work available for the employee, so he could not return to work for the employer until he had been released to work without restrictions.  Although the employee had no rehabilitation assistance after his injury and his release to light-duty work, “the failure of the employer to provide rehabilitation services does not eliminate the responsibility of the employee to make a diligent search within his limitations.”  Brown v. Minneapolis Elec. Steel Castings, 39 W.C.D. 207, 209 (Minn. 1986); see also Priglmeier v. Steller Concrete & Masonry, 65 W.C.D. 384, 400 (W.C.C.A. 2005); Mattson v. State, Dep’t of Public Safety, 48 W.C.D. 77, 80 (W.C.C.A. 1992), rev’d on other grounds, 494 N.W.2d 884, 48 W.C.D. 84 (1993).  A diligent job search is one that is reasonable under all the facts and circumstances.  Bauer v. Winco/Energex, 42 W.C.D. 762, 768 (W.C.C.A. 1989).  In this case, employee testified that he looked in the paper for jobs and asked his friends about jobs.  “Whether an injured employee makes a reasonably diligent search for suitable employment is a question of fact,” and a compensation judge’s decision in that regard “must be upheld unless manifestly contrary to the evidence.”  Hanmer v. Wes Barrette Masonry, 403 N.W.2d 839, 841, 39 W.C.D. 758, 761 (Minn. 1987), citing McClish v. Pan-O-Gold Baking Co., 336 N.W.2d 538, 36 W.C.D. 133 (Minn. 1983).  Substantial evidence supports the compensation judge’s finding that the employee did not conduct a diligent job search within his restrictions.

The record indicates, however, that the parties agreed the employee could return to work with the employer when he was released to work without restrictions.  Where there is a reasonable possibility that an employee will return to work with the employer, it may not be necessary for the employee to conduct an immediate search for employment to be eligible for temporary total disability benefits.  Jacobson v. Seaboard Farms, slip op. (W.C.C.A. May 6, 1996); Glasow v. Gresser Concrete Masonry, slip op. (W.C.C.A. Apr. 18, 1995).  See also Nelson v. Quality Pork Processors, No. WC07-138 (W.C.C.A. Oct. 3, 2007).  The compensation judge did not address whether the employee had a reasonable expectation of returning to work for the employer, and therefore, at least for some period of time, whether he would not have been required to search for alternate work.  Under the circumstances of this case, we remand for further consideration of this issue.

Two evidentiary issues were raised by the employer on appeal.  In its brief, the employer argues that the compensation judge erred by refusing to admit certain documentary evidence into the record.  First, we note that pursuant to Minn. Stat. § 176.411, subd. 1, a “compensation judge is bound neither by the common law or statutory rules of evidence nor by technical or formal rules of pleading or procedure.”  Evidentiary rulings are generally within the discretion of the compensation judge.  Bey v. Oxford Properties, Inc., 481 N.W.2d 40, 42, 46 W.C.D. 198, 201 (Minn. 1992); Ziehl v. Vreeman Constr. Co., slip op. at 5 (W.C.C.A. Oct. 15, 1991).  Further, this court’s jurisdiction is “limited to the issues raised by the parties in the notice of appeal . . . .”  Minn. Stat. § 176.421, subd. 6.  Issues not raised in the notice of appeal may not be addressed in the brief.  Minn. R. 9800.0900, supb. 1.  The employer did not file a notice of appeal.  Therefore, we will not address this evidentiary issue.

The employer also objects to the employee’s submission of an additional exhibit with his appellate brief that had not been submitted to the compensation judge during the hearing.  A letter from the employee’s attorney to his treating physician was submitted by the employee with his appellate brief.  This court’s function is to review the record created at the hearing before the compensation judge and to determine whether substantial evidence supports the compensation judge’s decision.  In reviewing cases on appeal, this court is limited to examination of the transcript of the hearing and evidence submitted to and considered by the compensation judge.  See Minn. Stat. § 176.421, subd. 1.  On appeal, this court may not consider evidence that is not contained in the record below.  Gollop v. Shale H. Gollop, D.D.S., 389 N.W.2d 202, 38 W.C.D. 757 (Minn. 1986); Glasgow v. Franciscan Health Cmty., No. WC04-434 (W.C.C.A. May 2, 2005).  We therefore have not considered the submitted letter on appeal.