The employer and insurer appeal from the compensation judge’s determination that the employee’s November 25, 2009, work injury is a substantial contributing factor in the employee’s current low back condition.  We affirm.

Thomas Sexton sustained a work injury on November 25, 2009, while he was employed by Alan Ritchey, Inc., and was unloading pallets from a semi trailer.  As he pulled on a strap which held down the pallets, it came loose suddenly and he fell backward, landing on his buttocks and striking his head against the side of the trailer.  He had a small cut to the back of his head and a sore neck but he decided not to seek immediate medical treatment.

The employee went to see a chiropractor, Dr. Allan Riesgraf, on November 30, 2009, for low back pain which he testified had developed shortly after the injury.  Dr. Riesgraf’s handwritten records are in evidence but are unreadable.  He saw Dr. Riesgraf on a number of occasions and stated that he stopped going there because there was no improvement in his condition.  On January 6, 2010, Dr. Riesgraf released the employee to return to work with no restrictions but treated the employee on four more occasions.

The employee had treated with Dr. Riesgraf previously for low back problems.  The treatment notes before the work injury are unreadable also so treatment details are not known.  The employee saw Dr. Riesgraf six times in September 1999, six times in September and October 2007, and five times in April 2008 for cervical and lumbar complaints.  He also saw Dr. Riesgraf eleven times for low back problems between May and July 2009.  The employee testified that it was his practice to go for treatments when “my back felt it was out of whack a little bit.”

The employee’s medical records in evidence disclose that before his 2009 work injury, he was treated for two work-related rotator cuff injuries that required surgery.  He also saw his family doctor at Crossroads Medical Clinic, Dr. Joseph Kandiko, for a variety of non-work-related medical conditions.  There is no record of the employee having any restrictions for his low back at the time of his injury in November 2009.

The employee started treating with Dr. Kandiko for his low back on January 21, 2010.  In his history, the employee related the onset of his low back pain to the work injury of November 25, 2009.  On exam, Dr. Kandiko found limited flexion, extension, and rotation, as well as positive straight leg raising on the right.  Dr. Kandiko provided the employee with work restrictions, referred him to physical therapy, and provided prescriptions for hydrocodone and flexeril.

Physical therapy did not relieve the employee’s symptoms, so Dr. Kandiko prescribed a Medrol Dose Pak and ordered a lumbar MRI, which was done on February 2, 2010.  The MRI was read as showing multilevel degenerative disc disease in the lumbar spine with moderate stenosis at L4-5, moderate to severe stenosis at L3-4, and foraminal narrowing with compression of the traversing L4 nerve root and the exiting L3 nerve root.  There was also some impingement in the L5 nerve root.  Dr. Kandiko referred the employee to Dr. Kevin Mullaney, an orthopedist at Twin Cities Spine Center.

The employee first saw Dr. Mullaney on February 25, 2010.  Dr. Mullaney noted the history of the work injury and also stated that the employee “had back pain in the past but nothing to this degree.”  Dr. Mullaney’s assessment was “back and leg pain consistent with neurogenic claudication secondary to spinal stenosis as above described, multilevel L2-3, L3-4, L4-5, and L5-S1.”  He recommended further physical therapy and a “left side L3-4 transforaminal epidural steroid injection.”  The employee was to return after these recommended procedures were done.

The employee returned on April 21 with complaints of significant back pain and leg pain.  The epidural steroid injection had helped for a few days but the symptoms had then returned.  Dr. Mullaney reviewed the MRI and examined the employee.  He noted significant dysfunction with no signs of symptom magnification.  Dr. Mullaney concluded

The employer and insurer sent the employee to Dr. David Florence on June 7, 2010.  In his report of June 15, Dr. Florence agreed with the diagnostic conclusions reached by the employee’s treating doctor although he stated the radiculopathy was not “definitive.”  Dr. Florence’s opinion was that the work injury represented a “temporary aggravation of his pre-existing condition.”  Dr. Florence also stated that the work injury was not a factor in the employee’s current low back symptoms.

In a letter to the employee’s attorney dated August 16, 2010, Dr. Mullaney responded to Dr. Florence’s report.  He stated he agreed that the majority of the employee’s symptoms were the result of a pre-existing condition but he noted that if the pre-existing condition was the only cause of the symptoms, the employee should have returned to a base line within three months of his injury and that had not happened.  He described the proposed surgery as a “complete salvage procedure in an effort to hopefully alleviate a portion of his pain in hopes of an improvement in his quality of life for potentially 10-15 years.”

Dr. Florence’s deposition was taken on December 9, 2010.  He restated his opinion as to causation and also testified that the surgery was not reasonable, at least in part due to the employee’s severe cardiac condition.

The employee filed a claim petition in August 2010, seeking approval of the surgery recommended by Dr. Mullaney.  The claim petition was heard by Compensation Judge William R. Johnson on December 14, 2010.  In his Findings and Order of January 4, 2011, the compensation judge found the work injury was a permanent aggravation of the employee’s pre-existing condition.  He determined that the surgery was not reasonable or necessary, adopting Dr. Florence’s opinion on this issue.  The employee’s request for surgery was denied.  The employer and insurer have appealed the determination of causation.  The employee has not appealed the denial of the surgery.

In his claim at the hearing, the employee contended that the November 2009 work injury was a substantial contributing factor in his low back condition and need for treatment.  His claim was supported by the opinion of his treating doctor, Dr. Mullaney.  The response of the employer and insurer was that the work injury was temporary and that current symptoms were due to a pre-existing condition.  That response was based on the opinion of Dr. Florence, the independent medical examiner [IME].

The compensation judge was given two conflicting medical opinions and the compensation judge’s choice between those opinions was the central issue of the case.  The compensation judge accepted the employee’s testimony that he had never had back pain to the extent he had after the work injury and that his low back pain never resolved after the work injury.  This testimony was a factor in Dr. Mullaney’s opinion.  The compensation judge also noted that Dr. Florence stated in his deposition that he had no reason to dispute that testimony.  The compensation judge adopted the opinion of Dr Mullaney on the question of causation.

This court has often cited to Nord v. City of Cook, 360 N.W.2d 337, 37 W.C.D. 364 (Minn. 1985), for the proposition that a decision based on a compensation judge’s choice between competing medical opinions is generally upheld where the opinion relied upon has adequate foundation.  We see no reason why that proposition should not be applied in the present case.

On appeal, however, the employer and insurer argue that the compensation judge’s adoption of Dr. Mullaney’s opinion was erroneous because it was based in substantial part on the employee’s testimony and, according to this argument, the employee’s testimony was unreliable because it was “inconsistent” with his medical records.  The alleged inconsistency cited by the employer and insurer is with regards to Dr. Riesgraf’s records.

The employer and insurer contend that Dr. Riesgraf’s records show that the employee’s condition improved during treatment so that the employee was released to work without restrictions as of January 6, 2010.  Therefore, it is argued that the work injury must have resolved by that time.  The evidence did not require the compensation judge to reach that conclusion.

It is true that Dr. Riesgraf released the employee to return to work without restrictions on January 6, 2010.  However, because Dr. Riesgraf’s handwritten treatment notes are unreadable, it is impossible to determine what Dr. Riesgraf’s conclusion as to the employee’s low back condition might have been as of that date.  Since Dr. Riesgraf saw the employee four more times after he had released the employee to work, including an appointment on the day before the employee saw his family doctor, the compensation judge was not required to accept the interpretation argued by the employer and insurer.  The employee’s treatment is consistent with his testimony that his back pain did not resolve after the work injury.

Ultimately, this case turned on the employee’s credibility.  Determination of the credibility of a witness is uniquely within the province of a compensation judge.  Brennan v. Joseph G. Brennan, M.D., 425 N.W.2d 837, 41 W.C.D. 79 (Minn. 1988); McLafferty v. R.S. Eden, No. WC07-218 (W.C.C.A. Feb. 4, 2008).  In the present case the compensation judge clearly found the employee’s testimony credible as to the nature and extent of his symptoms after the work injury.  The employer and insurer’s argument does not provide us with a basis to reverse that finding.

We conclude the compensation judge’s decision is supported by substantial evidence.  We affirm.