Granite City Roofing, National Fire Insurance Company of Hartford (CNA), and SFM, the appellants in this matter, appeal from the compensation judge’s finding that the employee’s right knee condition was a consequential injury that arose out of his work injuries on January 7, 1998, and November 17, 2000.  The employer and insurers also appealed the compensation judge’s finding that viscosupplementation injections were necessary and reasonable to cure and relieve the employee of the effects of those work injuries.  The employer and insurers maintained that the compensation judge erred in not making a finding regarding the nature and extent of the employee’s knee injury.  We affirm.

The employee was working as a roofer for the employer, Granite City Roofing, when he suffered admitted low back injuries from falls on January 7, 1998, and November 17, 2000.  CNA (National Fire) provided the employer’s workers’ compensation coverage for the January 7, 1998, injury.  SFM provided that coverage for the employer at the time of the employee’s November 17, 2000, work injury.

In 1998, the employee underwent a cervical fusion at C5-C6.  Subsequently, the employee underwent a two-level low back fusion surgery (L4-S1) in 2001.  The employee filed a claim petition in 2002 which was resolved by a full, final and complete stipulation between the parties.  Under the agreement, SFM was responsible for 60% of the employee’s low back injury and CNA the remaining 40%.  The stipulation left open medical expenses arising out of, among other things, the lumbar spine.  The stipulation closed out an earlier right knee injury incurred on August 11, 1997, as that injury was temporary and had resolved.

The employee continued to experience low back symptoms.  In 2003, the employee underwent further fusion surgery which extended the fusion to L3-L4.  In 2007, the fusion was extended to L2-L3.  The employee’s treating physician, Sunny Kim, M.D., noted that the employee exhibited “severe antalgic gait” during a follow-up examination on November 4, 2008.  The employee underwent further low back surgery on May 27, 2012, when a spinal cord stimulator was implanted.

The employee experienced several falls that resulted in a need for medical treatment.  On April 20, 2011, the employee fell on stairs, resulting in an emergency room visit.  At a follow-up examination by Dr. Kim, the fall is attributed to low back pain and the employee’s knee giving out.  On July 30, 2011, the employee was watching his sons install a sidewalk.  As the employee was going down steps toward the project, his right knee gave out and he fell, striking his right knee.

On September 26, 2011, the employee was examined by Joseph Nessler, M.D.  Dr. Nessler assessed the employee as having right knee prepatellar bursal swelling, but found the employee’s knee to be stable in ligamentous testing.

On October 3, 2011, the employee was examined by Mark Halstrom, M.D.  An MRI was taken which showed a partial ACL tear in the employee’s right knee.  Dr. Halstrom noted that the employee attributed the knee pain to his fall, which was caused by the employee’s instability walking due to the condition of his low back.  Dr. Halstrom diagnosed the employee as suffering from a torn ACL, a healing chronic MCL sprain, and mild prepatellar bursitis.  Subsequent chart notes indicate that the employee described his knees giving way frequently, sometimes resulting in falls.  In a chart note on October 17, 2011, Dr. Halstrom referenced the employee’s multiple surgeries and attributed the employee’s right knee condition to “the leg giving out on [the employee] because of his back condition . . . .”  (Joint Ex. A-5.)  Dr. Halstrom’s diagnosis was both a torn ACL and meniscus.  Dr. Halstrom directed that physical therapy be undertaken and ACL surgery be considered if the physical therapy did not address the employee’s symptoms.  Dr. Halstrom noted that Dr. Nessler had considered the possibility that the problem may have arisen from Mr. Holtslander’s low back (i.e. neurological), but subsequently concluded that the problem was in the right knee.

On January 16, 2012, the employee began a series of viscosupplementation injections and steroid injections.  When the employee did not respond to the initial viscosupplementation injections (Supartz), Dr. Halstrom substituted a different supplement (Orthovisc) due to Dr. Halstrom’s experiences with other patients.  Dr. Halstrom noted that the steroid injections reduced the employee’s right knee pain symptoms.  The viscosupplementation injections did not provide the employee with any relief of his right knee symptoms.

On October 31, 2013, Mr. Holtslander underwent an IME conducted by Dr. Paul Dworak.  Mr. Holtslander indicated that his legs started giving way after his first back surgery.  Dr. Dworak conducted a physical examination and noted that Mr. Holtslander had ROM in both knees from 0-140 degrees.  Dr. Dworak assessed the objective examination of the employee’s right knee as inconsistent with the reported instability and pain.  Dr. Dworak diagnosed the employee with resolved bursitis secondary to a fall.  Dr. Dworak opined that the employee was not experiencing knee instability or neurologic disorders arising from the employee’s low back condition.  Dr. Dworak relied in part on the absence of any mention of knee instability in the employee’s medical records in arriving at this opinion.  Dr. Dworak opined that none of the medical care received by the employee for treatment of his right knee was reasonable or necessary after Dr. Nessler’s examination on October 18, 2011.  Dr. Dworak also opined that any right knee injury arose out of the sidewalk incident rather than from Mr. Holtslander’s work injuries, relying on Dr. Nessler’s notes and the results of Dr. Nessler’s examination.

Mr. Holtslander filed a Claim Petition on July 18, 2011, and an Amended Claim Petition on August 11, 2014.  The employee sought approval of a cervical fusion, cervical CT scan, SI radiofrequency denervation, GERD treatment, and right knee treatment.

The matter was heard before a compensation judge at the Office of Administrative Hearings on January 23, 2015.  The parties stipulated to relative responsibility between the two insurers for various medical expenses.  The issues to be determined regarding the employee’s right knee were characterized by the compensation judge as “Whether the employee’s current right knee medical treatment constitutes medical treatment that is reasonable and necessary due to, and causally related to, the employee’s work-related back injuries of January 7, 1998 and November 17, 2000.”  Mr. Holtslander testified in support of his claim.  The employer and insurers relied upon the medical records of the employee introduced into evidence.  The compensation judge approved the request for SI joint RF treatment, the requested CT scan, and the treatment for the employee’s right knee condition.  The compensation judge denied the requested cervical fusion procedure and the requested treatment expenses for the employee’s GERD condition.  The employer and insurers appealed the award of right knee treatment expenses.

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 Products, 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.

Where an injury is determined to be compensable, the employer is responsible for any resulting medical treatment caused from the effects of the work injury unless there is a superseding, intervening cause that breaks the chain of causation.  Nelson v. American Lutheran Church, 420 N.W.2d 588, 590, 40 W.C.D. 849, 851 (Minn. 1988); Rohr v. Knutson Constr. Co., 305 Minn. 26, 29, 232 N.W.2d 233, 235, 28 W.C.D. 23, 26 (1975).  Liability continues despite an intervening, nonwork-related condition where the work-related injury is a substantial contributing cause of the ongoing disability.  Rogers v. Cedar Van Lines, 36 W.C.D. 125, 126-27 (W.C.C.A. 1983).  In this matter, the employee maintained that a result of his low back injuries was instability in his legs that caused them to give way on a frequent basis.  As a result of his legs giving way, the employee fell and suffered injuries to his right knee for which he seeks compensation.

The employer and insurers contend that the employee has not shown a causal connection between the admittedly compensable low back condition and a subsequent knee injury.  The employer and insurers rely on several notations in the employee’s treatment record and the IME opinion of Dr. Dworak in making this argument.  In addition, the employer and insurers maintain that the compensation judge relied on facts not in evidence when he made a finding that:

The employee responded that the treatment record, the employee’s testimony, and the express opinion of Dr. Halstrom amply demonstrated the connection between his low back condition and the weakness and instability resulting in a number of falls, ultimately resulting in the employee’s right knee injury.  As to the language indicated in Finding 20, the employee maintained that the compensation judge was only indicating that the number of back surgeries was consistent with employee’s description of instability leading to falls and the right knee injury.

Where the employee has support in the form of expert medical testimony and the compensation judge has found the employee’s testimony credible, this court has upheld the finding that the employee has suffered a consequential injury caused by the work injury.  Gora v. Winona Heating & Ventilation, slip op. (W.C.C.A. Jan. 27, 2003); see also Olson v. Executive Travel MSP, Inc., 437 N.W.2d 645, 41 W.C.D. 793 (Minn. 1989); Weston v. Univ. of Minn./Duluth, slip op. (W.C.C.A. May 20, 1999).  While the employer and insurers argue that Dr. Halstrom’s opinions lack foundation, the medical record demonstrates that there was a longstanding connection between the employee’s low back injuries and his unsteady gait, resulting in falls.  Mr. Holtslander’s testimony regarding the beneficial effects of the spinal cord stimulator, including improvement in both bilateral radicular pain and in gait, provided further evidence supporting the connection between the low back injuries and his knee injury.  Dr. Dworak based his opinion in part on a claimed lack of references to instability in Mr. Holtslander’s medical record.  That record contains a significant number of references to his knee instability linked to his low back condition.  Mr. Holtslander has met his burden to show that he suffered an injury to his right knee as a consequence of his work-related low back injuries.

The reference in finding 20 to five surgeries and the compensation judge’s inferred connection of the number of surgeries to the employee's knee injury is not supported by an explicit medical opinion.  There is a reference by Dr. Halstrom to the number of the employee’s back surgeries, but no explicit statement that the number of surgeries is in any way a demonstration of a connection.  This error does not change the outcome, however, as ample evidence independent of this perceived connection supports the compensation judge's award of benefits.

The employer and insurers maintain that the employee failed to demonstrate the reasonableness and necessity of the right knee treatment received by Mr. Holtslander.  They assert that the employee’s condition, as assessed by Dr. Dworak, did not support either the viscosupplementation treatment or steroid injections.  Further, the employer and insurers rely on the lack of benefit from the first round of viscosupplementation (Supartz) as demonstrating that second round (Orthovisc) was neither reasonable nor necessary to treat Mr. Holtslander’s right knee.  The employee contended that there is sufficient evidence in the record to support the compensation judge’s award of right knee treatment benefits.

The employee bears the burden of proof that medical treatment is reasonable and necessary to cure and relief from the effects of the work injury.  Adkins v. Univ. Health Care Ctr., 405 N.W.2d 233, 39 W.C.D. 898 (Minn. 1987).  In this matter there is a disagreement between the physicians as to whether the treatment received by Mr. Holtslander was appropriate to address the condition of his right knee.  The reasonableness and necessity of medical treatment sought under Minn. Stat. § 176.135 is a question of fact for the compensation judge.  Hopp v. Grist Mill, 499 N.W.2d 812, 48 W.C.D. 450 (Minn. 1993).  In arriving at a decision, the compensation judge must resolve conflicts in expert medical testimony, and the judge’s choice of expert opinion is usually upheld unless the facts assumed by the expert in rendering an opinion are not supported by the evidence.  Nord v. City of Cook, 360 N.W.2d 337, 37 W.C.D. 364 (Minn. 1985).  Where evidence is conflicting or more than one inference may reasonably be drawn from the evidence, the findings of the compensation judge are to be upheld.  Redgate v. Sroga’s Standard Serv., 421 N.W.2d 729, 40 W.C.D. 948 (Minn. 1988); Land v. Washington County Sheriff’s Dep’t, slip op. (W.C.C.A. Dec. 23, 2003).

In this matter, there were conflicts in the medical testimony regarding the condition of the Mr. Holtslander’s right knee.  These conflicts extended to what was shown on the imaging taken of that joint.  The compensation judge credited the opinion of Dr. Halstrom in awarding the requested medical treatment.  The testimony of Mr. Holtslander, accepted by the compensation judge, was that the steroid injections eased his right knee pain.  While the viscosupplementation treatment was ultimately not effective at addressing the employee’s right knee condition, there is an adequate basis in the record to support the compensation judge’s conclusion that the treatment was a reasonable and necessary effort to address the underlying cause of Mr. Holtslander’s ongoing right knee pain.  Since Dr. Halstrom had experienced differing results with other patients using a second viscosupplement after the initial trial was ineffective, there is a basis for concluding that the second round was also necessary and reasonable.

We conclude that substantial evidence supports the compensation judge’s determination that the viscosupplementation and steroid injections were necessary and reasonable to treat Mr. Holtslander’s right knee condition.  For that reason, we affirm the compensation judge’s decision.

The employer and insurers assert that the compensation judge erred by failing to make a finding regarding the nature and extent of Mr. Holtslander’s right knee injury.  They did not indicate why such a finding is necessary in this proceeding.  The employee responded that the nature and extent of the employee’s right knee condition was adequately identified in the compensation judge’s findings to the extent required to resolve the issues placed before him.

The compensation judge addressed the issues as they were presented to him by the parties.  A compensation judge is not free to address issues that were not presented and argued by the parties.  Ounasser v. Golden Living Ctr. Rochester W., No. WC13-5565 (W.C.C.A. Sept. 4, 2013); Dawson v. Univ. of Minn., slip op. (W.C.C.A. May 6, 1999) (citing Kulenkamp v. Timesavers, Inc., 420 N.W.2d 891, 40 W.C.D. 869 (Minn. 1988)).  A finding regarding the nature and extent of an injury is not required prior to approving medical treatment.  See, e.g., Ostertag v. Kottkes Bus Serv., slip op. (W.C.C.A. November 14, 2001) (prior order did not make findings regarding nature and extent of injury as treatment was ongoing).  Upon review of the record, this court notes that the compensation judge addressed the issues that were presented to him.  There is no error in failing to address an issue that was not before the compensation judge.

Mr. Holtslander bore the burden of proof to show that his right knee injury was the result of a fall caused by his low back injuries.  Mr. Holtslander presented evidence through an extensive medical record, his own testimony, and expert medical opinion that his falls were the result of instability and altered gait arising from his low back injuries.  The compensation judge found that this evidence was sufficient to meet the employee’s burden and awarded benefits.  Having carefully reviewed the record, we conclude that the compensation judge’s findings, except as noted above, are supported by substantial evidence and not clearly erroneous.  The single portion of a finding that was not supported by substantial evidence amounts to harmless error.  We therefore affirm the compensation judge’s award.