The employee appeals from the compensation judge’s determination that the employee’s work injury of May 5, 2012, was temporary in nature and that the employee’s claims for payment of medical expenses beyond August 6, 2012, including expenses for a right knee arthroplasty, were not causally related to a work-related injury.  We affirm.

The employee, Zachary Burns, worked as an overnight stocker for the employer herein, Wal-Mart.  On May 5, 2012, the employee was “zoning,” meaning organizing and straightening products on shelves, when he bent down to the bottom shelf to pull a product forward.  As he bent down, he felt a pop in his right knee.  He felt immediate shooting pain and had difficulty standing back up.

The employee reported the incident the next day, and he presented to the Stillwater Medical Group on May 6, 2012.  The employee was initially diagnosed with a right knee strain.  He was taken off work for two days and told to rest, use ice, and elevate his knee.  The employee followed up with Dr. Nicole Vik at Entira Family Clinics on May 7, 2012.  He was complaining of moderate to severe right knee pain.  Doctor Vik recommended an MRI for the right knee.  Doctor Vik reviewed the MRI with the employee on May 14, 2012.  She noted that the MRI showed a lateral femoral condyle irregularity, which she stated was likely related to an area of osteochondral injury.

The employee continued to treat with Dr. Vik and the Entira Clinic group in June and July 2012.  He was eventually referred to Dr. Jeffrey Furmanek at Summit Orthopedics, and he saw Dr. Furmanek on July 27, 2012.  At that time, the employee was continuing to complain of right knee pain with an inability to bear weight.  Doctor Furmanek noted an antalgic gait with general tenderness.  He opined that the MRI showed a chondral irregularity with underlying bone marrow edema without ligament or meniscal tearing.  Doctor Furmanek diagnosed the employee with right knee chondromalacia.  Doctor Furmanek also gave the employee an injection of Marcaine in his right knee.

The employee began a course of physical therapy through Summit Orthopedics on August 6, 2012.  During his intake for physical therapy, the employee filled out a questionnaire.  He indicated that his pain, at worst, would be 2 out of 10.  His current pain was listed at 1 out of 10.  When he was at his best, he indicated that he had “no pain.”  The initial physical therapy evaluation indicated that the employee was complaining “of resolving right knee pain.”  The employee reported that his injection had “helped significantly” and that “[h]e now has minimal to no pain and states that he feels just some ‘pressure’ [i]n the knee and it will crack at times.”  The employee said that he was not restricted in any of his daily activities and was able to do stairs normally without pain.  He informed the physical therapist that he was scheduled to return to full duty work on August 7, 2012.  The physical therapist recommended four to eight additional physical therapy sessions.  The employee, however, did not return to physical therapy, and he was later discharged on September 26, 2012.

The employee returned to see Dr. Furmanek on August 29, 2012.  At that time, he reported an episode, about four days earlier, where his knee locked up at work.  The employee indicated that he had to sit down for a half an hour, and he said he had cracking, popping, and pain.  On examination, Dr. Furmanek noted that there was generalized joint pain and some crepitus to the patellofemoral joint, with stable ligament.  Doctor Furmanek diagnosed the employee with right knee trochlear chondromalacia, along with failed outpatient non-operative therapies.  Doctor Furmanek recommended a right knee arthroscopy.

In describing the August 25, 2012, incident, the compensation judge found that the employee “was walking to the end of an aisle to get freight off of a pallet when his right knee locked.”  The compensation judge also noted that the employee “testified to feeling a grinding sensation in his knee after it unlocked.”

At the request of the employer and insurer, the employee underwent an independent medical examination with Dr. Thomas Nelson on October 4, 2012.  Doctor Nelson opined that the employee did sustain an osteochondral injury on May 5, 2012, while working at the employer.  The injury was consistent with the mechanism of injury described.  Doctor Nelson also indicated that the employee had “marrow edema in the lateral femoral condyle, which is consistent with an acute injury,” which was noted on the May 2012 MRI scan.  Doctor Nelson then opined that the May 5, 2012, work injury “resolved as of August 6, 2012, when Mr. Burns was seen by the physical therapist and had full range of motion with no complaints of pain.”  Doctor Nelson indicated that at the time of the October 2012 examination, there was no medical evidence to suggest chondromalacia patella.  Doctor Nelson did not agree that surgery would be medically necessary to address the work injury, and he noted that the employee’s current clinical findings might suggest a medial meniscus tear.  However, he opined that the tear was not evidenced on the MRI scan done in May 2012.  Doctor Nelson recommended a new MRI scan to address the employee’s current examination, consistent with a medial meniscus injury, but stated that the MRI scan would be “entirely unrelated to the work injury of May 5, 2012.”

The employee returned to see Dr. Furmanek on December 7, 2012.  Doctor Furmanek noted a separate incident in August 2012 that caused “recurrent” symptoms, and he recommended a second MRI as well.

The employee underwent a second MRI on January 17, 2013.  On January 23, 2013, Dr. Furmanek noted that the new MRI showed a full-thickness articular cartilage defect that persisted over the most posterior aspect of the lateral femoral condyle and evidence of lateral riding patella with chondromalacia lateral facet.  Doctor Furmanek planned surgery, and the employee underwent a right knee arthroplasty on February 11, 2013.

Doctor Nelson also reviewed the employee’s January 2013 MRI and issued a supplemental report dated March 18, 2013.  Doctor Nelson indicated that “there is really no evidence of significant bone marrow edema like there was on the previous MRI.”  Doctor Nelson indicated that the change in the January 2013 MRI “suggests lateral patellar tracking as evidenced by chondromalacia along the lateral patellar facet and lateral patellar subluxation.”  Doctor Nelson indicated that this finding on the new MRI scan did not change his opinions from the previous IME in any way.  He did not attribute the lateral patellar tracking issues to the employee’s May 2012 injury.  Rather, he opined that the employee’s current issues were personal to the employee due to his anatomy.

Doctor Furmanek also wrote a follow-up report dated May 9, 2013.  He indicated that the employee had sustained an injury in the nature of right knee chondromalacia as a result of the May 5, 2012, incident.  He opined that the employee’s May 5, 2012, injury was a substantial contributing factor to his right knee condition and subsequent disability, as well as his need for medical treatment and restrictions.  He also opined that the August 25, 2012, incident was a re-aggravation of the May 5, 2012, injury.  Doctor Furmanek indicated that the first MRI of the employee’s right knee, which was taken shortly after the May 5, 2012 injury, showed a full-thickness cartilage injury with bone marrow edema, suggesting an acute osteochondral injury.

The parties eventually proceeded to hearing before Compensation Judge William Marshall on May 29, 2013.  The compensation judge was asked to determine whether the surgery in February 2013 was causally related to either the May 5, 2012, or August 25, 2012, incidents.  The compensation judge was also asked to determine whether the intervention claims for medical treatment after August 6, 2012, were compensable.  The compensation judge noted that as of August 6, 2012, the employee was reporting being pain free as a result of his May 5, 2012, work injury.  He returned to full-duty work the next day and continued until his knee locking incident on August 25, 2012.  In his memorandum of law, the compensation judge found that Dr. Nelson’s opinion was more persuasive than Dr. Furmanek’s given the evidence and testimony presented.  The compensation judge determined that the employee’s surgery and medical treatment beyond August 6, 2012, were not causally related to either a May 5, 2012, or an August 25, 2012, work injury.  The employee appeals.

In reviewing cases 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, “[f]actfindings 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 Foods Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).  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.”  Id.

On appeal, the employee argues that substantial evidence does not support the compensation judge’s denial of medical expenses after August 6, 2012.

Here, the compensation judge credited Dr. Nelson’s opinion and found that “the employee’s injury resolved as of 8/6/2012 when the employee had no complaints of pain and a full range of motion.”  It is the role of the compensation judge to resolve conflicts in expert medical testimony, and his or her choice of expert opinion is generally upheld on appeal unless the facts assumed by the expert in rendering his opinion are insufficient or not supported by the evidence.  See Nord v. City of Cook, 360 N.W.2d 337, 37 W.C.D. 364 (Minn. 1985).

The employee argues that the compensation judge and Dr. Nelson improperly indicated that the employee did not have any pain at the time of his physical therapy evaluation on August 6, 2012.  We acknowledge that the employee did indicate in his physical therapy intake form on August 6, 2012, that his pain level was 1 out of 10.  However, he also indicated that he had periods of time with “no pain.”  The employee said his injection had “helped significantly” and that “[h]e now has minimal to no pain.”  The employee also said that he was not restricted in any of his daily activities and was able to do stairs normally without pain.

The employee argues that the August 6, 2012, evaluation took place within ten days of a cortisone injection, which may have masked the pain but not the ongoing pressure and “cracking” sensations the employee was reportedly experiencing.  However, on August 6, 2012, the physical therapist indicated that the employee’s right knee pain was “resolving.”  At the conclusion of the visit on August 6, 2012, the physical therapist recommended four to eight additional physical therapy sessions.  However, the employee returned to full-duty work on August 7, 2012, and he did not return for additional physical therapy or any other treatment until he saw Dr. Furmanek again on August 29, 2012, and reported the August 25, 2012 incident.

Ultimately, the medical records indicate that as of August 6, 2012, the employee had periods with “no pain,” he was not restricted in any of his daily activities, he was once again able to do stairs normally without pain, and the physical therapist described his pain as “resolving.”  The employee returned to full-duty work on August 7, 2012, and he did not return for treatment until after the August 25, 2012, incident.  Therefore, it was reasonable for the compensation judge to rely upon Dr. Nelson’s opinions and determine that the employee’s May 5, 2012 injury had resolved as of August 6, 2012.

The employee then argues that the August 25, 2012, incident was a continuation of the May 5, 2012, injury.  The employee cites a number of purported similarities in the medical records from before and after the August 2012 incident.  He also cites the two MRI reports and argues that Dr. Furmanek indicated that no new pathology had been shown following the January 2013 MRI.  In addition, the employee argues that during the surgery, Dr. Furmanek did not do anything to address the patellar maltracking diagnosed by Dr. Nelson.

Doctor Nelson, however, related the ongoing treatment after August 6, 2012, to the employee’s personal anatomy.  The employee concedes that he is not challenging the foundation for Dr. Nelson’s opinions.  Rather, his arguments at hearing focused on the experts’ opinions and the weight to be afforded those opinions.  Again, the compensation judge is given discretion to assess the weight and sufficiency of a medical expert’s opinion and to resolve any conflicting medical opinions.  Nord, 360 N.W.2d 337, 37 W.C.D. 364; see also Ruether v. State, Mankato State Univ., 455 N.W.2d 475, 477-48, 42 W.C.D. 1118, 1121-22 (Minn. 1990).

The compensation judge analyzed the employee’s testimony regarding his symptoms, the medical records, and the well-founded causation opinions of Dr. Furmanek and Dr. Nelson regarding the ongoing treatment at issue and its relation to the work injuries.  We acknowledge that the employee presented evidence that may support his arguments, including Dr. Furmanek’s opinions.  The employer and insurer, however, presented evidence to support their position that the employee’s injuries resolved as of August 6, 2012, including Dr. Nelson’s opinions.  It is not the role of this court to evaluate the credibility and probative value of witness testimony and choose different inferences from the evidence than the compensation judge.  See Krotzer v. Browning-Ferris/Woodlake Sanitation Serv., 459 N.W.2d 509, 512-13, 43 W.C.D. 254, 260-61 (Minn. 1990); Redgate v. Sroga’s Standard Serv., 421 N.W.2d 729, 734, 40 W.C.D. 948, 957 (Minn. 1988).  Because there is substantial evidence to support the compensation judge’s denial of medical treatment after August 6, 2012, we affirm.