The employer, Luoma Egg Ranch, Inc., and its insurer, American Compensation Insurance/RTW Group, appeal from the compensation judge’s determination that the employee, Mary K. Anwiler, sustained an injury to her cervical spine as a result a specific injury on May 8, 2009.^[1]  The employer and insurer also appeal the compensation judge’s determination that the employee sustained Gillette injuries to her left thumb, left middle finger, and left ring finger, culminating on April 15, 2010; and from the judge’s awards of 3.5 percent permanent partial disability related to the cervical spine and 3.5 percent permanent partial disability related to the lumbar spine.  The employer and insurer also appeal the compensation judge’s failure to consider the issues raised by the employer and insurer in their closing written argument.  We affirm.

On September 1, 1972, the employee was hired to perform multiple services for the egg-laying operations at Luoma Egg Ranch.  From 1972 to April 15, 2010, the employee worked at the ranch picking eggs, cleaning egg carriers with a pick, brush, or rag, cleaning break rooms, sweeping floors, mopping floors, washing walls, vacuuming rugs, cleaning bathrooms, packing eggs, removing debris from under belt holders, and cleaning and changing water cups.^[2]  The physical demands of the job required standing, walking, sweeping, and crawling. ^[3]  At times the employee worked the full-time job eight hours per day or more, seven days per week.  By the time of the hearing in March 2014, the employee was working eight hours per day or more, five days a week.^[4]

At the hearing, the employee testified that she injured her neck, mid back, hip and low back on May 8, 2009, when a raised walkway on which she was walking “gave way.”^[5]  The employee initially sought treatment with a chiropractor, Dr. Kyle Hams, on May 11, 2009.^[6]  At that time the employee filled out a patient health questionnaire listing neck pain, low back pain, shoulder pain, wrist pain, and hand pain as present conditions.  On examination, Dr. Hams noted trigger point and spasm in the cervical muscles, along with paraspinal muscle spasm in the low back from L1 to L5.  Dr. Hams performed a Kemps test and cervical compression tests.  The Kemps test caused low back pain.  Cervical compression tests caused neck pain.  Dr. Hams noted misalignment in the low back and neck, including L5 and C4, along with mild to moderate tenderness in those areas.  His diagnosed cervical and lumbar subluxations and cervical and lumbar sprain/strains.

On May 13, 2009, the employee returned to see Dr. Hams for low back, mid back, and neck pain.^[7]  Dr. Hams noted objective symptoms in her low back and neck, although he did not specifically describe those symptoms.  The employee continued to treat with Dr. Hams into mid-August 2009.  Dr. Hams continued to note objective symptoms in the neck at C2 and C4, primarily.  He also noted objective symptoms in the low back at L5, primarily.  He did not give a specific description of those symptoms.  The employee remained symptomatic, and by late July of 2009, the employee was still reporting ongoing neck, mid back, and low back pain.  She was improving overall, but she did experience an increase in symptoms after returning to full-time work.  On July 30, 2009, Dr. Hams sent a letter to the insurer requesting approval for additional treatment citing the employee’s increase in pain with her release to full duty and return to work.  On August 12, 2009, Dr. Hams again made note of the employee’s objective symptoms at C4 and L5, but did not provide a specific description.  He again commented on her overall improvement, but also determined the employee had not reached maximum medical improvement.  The insurer denied Dr. Hams’ request for further treatment.

The employee treated at Gateway Family Health Clinic in September and December 2009 for low back and left hip pain.^[8]  On September 8, 2009, the employee was noted to have tenderness with palpation.  On December 3, 2009, she was noted to be “tender over the left low back into the left hip.”  The employee underwent a course of physical therapy from September 2009 through January 2010 to treat her low back and left hip pain.^[9]  She underwent an SI joint injection at Gateway Family Health Clinic on June 23, 2010.  At that appointment she was noted to have pain and tenderness over the left hip/SI area, and tested positive for flexion, abduction, and external rotation (FABER) tests on the left side.  The employee noted some relief from the injection procedure.  In the summer of 2011, she experienced some additional pain with symptoms and underwent physical therapy at Mercy Hospital in July 2011.^[10]  Her diagnosis at that time was low back pain, piriformis syndrome, greater trochanteric bursitis, and right lumbar radiculopathy.

The employee alleged that she sustained a Gillette injury involving her left thumb, left middle finger, and left ring finger, culminating on April 15, 2010.  The employee testified that about 15 to 20 years before the claimed injury date, she began to notice symptoms in her hands and wrists, which progressed to include tingling, numbness, bending and crookedness in the fingers, difficulty moving her fingers, including the thumbs, decreased dexterity, an inability to make a fist, and weakness in her hands while lifting.^[11]  The employee testified that her symptoms became progressively worse over the years.  She testified to the difficulties in performing her day to day tasks such as grasping eggs, and how she had to modify her broom so that she could continue to try to grasp the broom and push it.^[12]

The employee also testified that her symptoms went on for many years, but they became “unbearable” in the spring of 2010.  She was eventually referred to a surgeon, Dr. Michael Momont with Orthopedic Associates of Duluth, on September 8, 2010.^[13]  Dr. Momont noted bilaterally positive Tinel’s signs and restricted range of motion of the left long finger and left ring finger, along with some hypertrophic changes in the digits.  Dr. Momont diagnosed the employee with carpal tunnel syndrome, and he performed carpal tunnel releases in December 2010 and January 2011.

Dr. D. M. Van Nostrand conducted an independent medical evaluation at the employee’s request on October 17, 2011.^[14]  Dr. Van Nostrand reviewed the employee’s medical records and conducted a physical examination of the employee.  On examination of the employee’s neck, he noted decreased lateral flexion, at 30/45 degrees right and left, as well as decreased rotation, 60/80 degrees right and 70/80 degrees on the left.  He also noted cervical compression positive for pain as well as a positive Spurling’s test.  Dr. Van Nostrand diagnosed the employee with cervical pain syndrome.  He opined that the employee met the requirements of Minn. R. 5223.0370, subp. 3.B., and he specifically stated that the employee had “symptoms of pain and stiffness in the region of the cervical spine substantiated by persistent objective clinical findings with muscle tightness and decreased passive range of motion.”

Dr. Van Nostrand’s examination of the employee’s low back appeared to be relatively normal, and he did not indicate that there was any decreased range of motion or spasm present at the time of the examination.^[15]  However, Dr. Van Nostrand did diagnose the employee with lumbar pain syndrome, and he also indicated that she had sacroiliac joint pain.  Dr. Van Nostrand opined that the employee met the requirements of Minn. R. 5223.0390, subp. 3.B. for lumbar pain syndrome, and he stated that the employee had “symptoms of pain and stiffness in the region of the lumbar spine substantiated by persistent objective physical findings and treatment, no radiographic abnormalities.”  He also stated that “in my opinion, this accounts for what she describes as hip pain as well.”

Dr. Van Nostrand also examined the employee’s hands and wrists, and he listed a number of diagnoses for the employee, including amputation of the left index finger^[16] and decreased range of motion in the left thumb, large finger, and ring finger.^[17]  He also gave a causation opinion as follows:

At the employer and insurer’s request, the employee underwent an independent medical examination with Dr. Scott McPherson on April 26, 2012.^[18]  On examination, Dr. McPherson noted the partial amputation of the employee’s left index finger and “diffuse osteoarthritic changes” in the middle, ring, and small fingers, including limited flexion to a midrange position.  “Examination of the neck revealed good range of motion with no signs of cervical radiculopathy,” although the employee noted that if she moved her neck to “an extreme level,” she would experience cracking.

Dr. McPherson assessed the employee with bilateral idiopathic carpal tunnel syndrome and diffuse osteoarthritis in her hands, mainly at the DIP and PIP levels, more so on the left than right.^[19]  He opined that these conditions were not work related.  Dr. McPherson also referred to “the history of a fall where she wrenched her left hip.”  He noted ongoing SI joint pain and symptoms in the left hip.  He opined, “I would anticipate that the prognosis for her low back, which includes the SI joint and her left hip, are stable conditions and I do not anticipate any immediate treatment.”  Dr. McPherson indicated that, by history, the employee injured her left hip and SI joint in her fall at work, and he stated that “this would be work related.”  Dr. McPherson also noted the employee’s history of cervical pain, and he opined that this “appears to be just a likely degenerative neck condition that she treats with occasional chiropractic treatment.”

The employee filed a claim petition in June 2013, and the case came on for hearing before a compensation judge on March 6, 2014.  The employer and insurer filed an answer that included a general denial of the employee’s claims in their entirety.  The employer and insurer did, however, stipulate that the employee sustained an injury to her low back arising out of and in the course and scope of her employment on May 8, 2009.  The employer and insurer further stipulated that the employee sustained a Gillette injury in the nature of bilateral carpal tunnel syndrome arising out of and in the course and scope of her employment, culminating on April 15, 2010.  The employer and insurer maintain, however, that the employee did not sustain injuries as alleged to her neck or her left thumb, middle, or ring fingers as a result of her employment.  The compensation judge summarized the issues for consideration at hearing as follows in her findings and order:

At hearing, the compensation judge heard testimony from the employee, and the parties submitted additional evidence, including a written job description, medical records from Dr. Hams, Mercy Hospital, Gateway Family Health Clinic, Orthopedic Associates of Duluth, and the independent medical reports from Dr. Van Nostrand and Dr. McPherson.  At hearing, the parties did not give opening statements.  They did submit written closing arguments after the conclusion of the hearing.  Ultimately, the compensation judge determined that the employee sustained injuries to both the cervical and lumbar spines as a result of the incident on May 8, 2009.  She awarded 3.5 percent permanent partial disability related to the cervical spine and 3.5 percent permanent partial disability related to the lumbar spine.  The compensation judge also determined that the employee’s work activities over the years were substantial contributing factors in the development of Gillette injuries to the employee’s left thumb, left middle finger, and left ring finger, culminating on April 15, 2010.  The compensation judge further found that the employee’s work-related personal injuries involving her left thumb, left middle finger, and left ring finger are permanent personal injuries.  However, the compensation judge indicated that permanent partial disability ratings could not be assigned for those body parts yet because there is insufficient information in the medical records with regard to degrees of extension, flexion, and other measurements necessary to ascertain the correct percentages of loss of motion as required by Minn. R. 5223.0480, subp. 4.B.(1)(b).  The compensation judge also explained that she did not consider the employer and insurer’s notice/statute of limitations defenses because they were not raised until the submission of written closing arguments.  The employer and insurer appeal.

Appellants raise five issues on appeal:  (1) whether the employee sustained a personal injury to her cervical spine arising out of and in the course of her employment on May 8, 2009; (2) whether the employee incurred a 3.5 percent whole body impairment related to her cervical spine injury; (3) whether the employee incurred a 3.5 percent whole body impairment related to her low back injury; (4) whether the employee sustained a Gillette-type injury to her left thumb, left middle finger, and left ring finger arising out of and in the course of her employment culminating on April 15, 2010; and (5) whether the compensation judge committed an error of law by refusing to address an issue raised in the employer and insurer’s written closing argument for the stated reason that opposing counsel was not given notice of the issue and a reasonable opportunity to be heard.

The Workers’ Compensation Court of Appeals will uphold the factual findings of the compensation judge if they are supported by substantial evidence and were reached through application of the correct legal standard.^[20]  Substantial evidence is such relevant evidence as a reasonable mind might accept as adequate to support a conclusion.^[21]  In reviewing for substantial evidence to support the compensation judge’s findings, we do not make credibility determinations.^[22]  Where oral evidence allows reasonable minds to differ as to whether the employee’s injuries are work related, the responsibility for that decision rests with the compensation judge.^[23] With this standard of review in mind, we consider the employer and insurer’s arguments.

The employer and insurer contend that the record lacks substantial evidence to support the compensation judge’s finding that the employee suffered a personal injury to her cervical spine on May 8, 2009.  We disagree for the reasons addressed below.

Factual findings, including determinations of credibility, may be implicit in the decision of a compensation judge and need not be expressed in order to meet the substantial evidence rule.^[24]  In the present case, the compensation judge reached her conclusions of law, in large part, on credibility-based findings.  She implicitly found the employee’s statements regarding her injury in 2009 to be credible and consistent with the medical treatment records from Dr. Hams, Mercy Hospital, Gateway Family Health Clinic, Orthopedic Associates of Duluth and with Dr. Van Nostrand’s expert medical opinions.  Generally, our review of witness credibility focuses on the compensation judge’s assessment of a witness and on the deference due to the judge who observes the demeanor of the witness and sees her testimony on direct, cross, and redirect examination.^[25]  Here, the compensation judge implicitly found the employee credible and considered her testimony reliable and accurate in determining what was factual and, ultimately, reaching conclusions about the nature and extent of the employee’s work-related injuries.  The weight given to the oral evidence, together with all the admissible evidence, established the causal link between the employee’s injury in May of 2009 and the cervical condition on which the permanency rating was based.

The Compensation Judge found that the employee sustained a 3.5 percent whole body impairment related to her 2009 cervical injury.  The compensation judge’s rating was based on Minn. R. 5223.0370, subp. 3.B., which provides a 3.5 percent permanency rating for cervical pain where there are symptoms substantiated by persistent objective clinical findings.^[26]  A compensation judge’s finding regarding the rating of permanent partial disability is one of ultimate fact and must be affirmed if it is supported by substantial evidence.^[27]  It is not the role of this court to choose from among possible inferences different from those drawn by the compensation judge.^[28]

The employer and insurer contend that the compensation judge’s award of 3.5 percent permanency is unsupported by substantial evidence.  They argue that while referencing the reports from the doctors, the judge actually made no findings concerning evidence of persistent objective clinical findings required by the rule at issue.  The employer and insurer assert that since there is no documentation of any objective clinical findings of involuntary muscle tightness or decreased range of motion, there is no substantial evidence as required by Minn. R. 5223.0370, subp. 3.B. to support a finding of 3.5 percent permanent partial disability.  We are not persuaded by the employer and insurer’s argument.

The records of Dr. Hams contain findings consistent with an injury to the left L5, T8, and C4 levels.  Dr. Hams’ records reference mid-back soreness and neck pain.  Dr. Van Nostrand reviewed the medical records from Dr. Hams, Mercy Hospital, Gateway Family Health Clinic, and Orthopedic Associates of Duluth, and his report contains firsthand observations on examination, which include findings of a decrease in the rotation of the cervical spine.  Specifically, Dr. Van Nostrand’s findings on examination included decreased lateral flexion at 30/45 degrees right and left, as well as decreased rotation 60/80 degrees right and 70/80 degrees on the left.  Dr. Van Nostrand also performed a cervical compression test and found it positive for pain.  Given these findings on examination and the employee’s medical history, Dr. Van Nostrand was of the opinion that the employee met the requirements of subpart 3.B. of the rule, and he cited “symptoms of pain and stiffness in the region of the cervical spine substantiated by persistent objective clinical findings with muscle tightness and decreased passive range of motion.”^[29]

The compensation judge was reasonably entitled to interpret these facts and observations from the employee’s medical records and medical expert as persistent objective clinical findings and conclude that the employee’s condition was most consistent with subpart 3.B. of the rule.  The clinical findings provide substantial support for the compensation judge’s finding of permanent partial disability to the cervical spine.

In addition to the rating for the cervical spine, the compensation judge found that the employee sustained a 3.5 percent whole body impairment related to her lumbar spine as a result of the 2009 injury.  The compensation judge based this rating on Minn. R. 5223.0390, subp. 3.B., which provides a rating for lumbar pain where there are symptoms substantiated by persistent objective clinical findings.^[30]

The employer and insurer stipulated that the employee sustained a work injury to her low back on May 8, 2009, but they contend that the compensation judge’s award of a 3.5 percent rating is unsupported by substantial evidence.  They argue that while referencing the medical reports, the compensation judge made no findings concerning evidence of persistent objective clinical findings as required by the rule.  The employer and insurer assert that because there is no documentation of any objective clinical findings of involuntary muscle tightness or decreased range of motion, there is no substantial evidence to support an award of 3.5 percent permanent partial disability pursuant to Minn. R. 5223.0390, subp. 3.B.  Given the evidence in the record, we are not persuaded by the employer and insurer’s arguments.

As with the neck, Dr. Hams continued to note objective symptoms in the low back through mid-August 2009.^[31]  Dr. Hams noted some improvement followed by an increase in the employee’s symptoms after she returned to work.  Additional medical treatment was denied by the insurer at a time when Dr. Hams was of the opinion that the employee was not at maximum medical improvement.  Physicians at Gateway Family Health Clinic also noted ongoing tenderness over the low back and left hip when the employee treated there in 2009 and 2010.^[32]  A sacroiliac joint injection in June 2010 provided some relief, but the employee continued to be symptomatic.^[33]  The employee also submitted to a flexion, abduction, and external rotation (FABER) test, which was positive and which identified the presence of musculoskeletal pathologies in the hip and lumbar spine to support a disability under the schedule.^[34]  More than a year after the 2009 injury, the employee followed up with Dr. Mark Petry at Gateway Family Health, complaining of continued left hip pain that she said was worse with crawling at work or pushing a squeegee.^[35]  Dr. Petry associated the employee’s symptoms to the May 8, 2009, incident, and he noted in his report the continued presence of left hip pain since the injury date.  The employee also underwent physical therapy in July 2011, at which time the records reflect low back pain and now reported radicular symptoms into her right leg.^[36]

Dr. McPherson and Dr. Van Nostrand provided medical opinions that the employee had sustained an injury to her left hip and SI joint at the time of her fall in 2009.  Dr. Van Nostrand was of the opinion that this condition accounted for what the employee noted as unremitting pain in the low back and left hip.^[37]  Dr. McPherson discussed the lumbar spine injury as an injury inclusive of the hip and SI joint.^[38]  Both doctors acknowledged the chronicity of pain associated with the lumbar injury.

The compensation judge analyzed the medical reports at length in her memorandum of law, and it is clear that she carefully reviewed all the admissible evidence.  The compensation judge was reasonably entitled to interpret these facts and observations from the employee’s medical records, including the expert opinions as persistent objective clinical findings and conclude that the employee’s low back condition was most consistent with Minn. R. 5223.0390, subp. 3.B.  As such, the clinical findings provide substantial support for the judge’s finding of permanent partial disability to the lumbar spine.

We conclude that the judge properly exercised her judgment in weighing all the evidence and making a determination on the disability ratings for the cervical and lumbar spine, and we affirm.

The employer and insurer stipulated that the employee sustained a Gillette-type work injury^[39] in the nature of bilateral carpal tunnel syndrome.^[40]  They contend, however, that the evidence was not adequate to sustain the finding that “[t]he employee suffered a Gillette-type personal injury to her left thumb, to her left middle finger, and to her left ring finger . . .”^[41]  The employer and insurer maintain that the finding was based on an inaccurate view of the medical evidence and made without foundation from any expert medical opinion.  To that end, they argue the finding was based on an erroneous application of law.  We are not persuaded by the employer and insurer’s arguments.

The compensation judge reached her conclusions of law largely on credibility-based findings.  In this case, the judge’s finding that the employee “suffered a Gillette-type injury to her left thumb, to her left middle finger, and to her left ring finger, arising out of and in the course of her employment with the employer . . .”^[42] is an implicit conclusion that the employee’s direct testimony regarding her day-to-day job duties and symptoms over a period of thirty-eight years was credible and consistent with the other evidence^[43] and facts in the case.  The compensation judge so much as stated such in her memorandum.

In addition, Dr. Van Nostrand reviewed medical records from Orthopedic Associates of Duluth, Dr. Hams, Gateway Family Health Clinic, and Mercy Hospital, and he discussed them in detail in his December 13, 2011, Independent Medical Evaluation report.^[44]  The employer and insurer argue that Dr. Van Nostrand was the only medical provider to diagnose a finger injury, and they argue that he did not give any causation opinion attributing the employee’s finger injury to her work activities.  We disagree.

Dr. Van Nostrand listed a number of diagnoses for the employee, including the amputation of the left index finger and subsequent gangrene.  On examination, Dr. Van Nostrand found the employee unable to make a fist and also found decreased range of motion in the left thumb, large finger, and ring finger consistent with osteoarthritis.^[45]  He also gave a causation opinion as follows:

The employer and insurer ask us to reverse the finding of a Gillette injury, claiming the facts do not support the judge’s conclusion.  We decline to do so.

Proof of a Gillette injury mainly depends on medical evidence,^[46] and it is the function of the compensation judge to determine the weight to be given any piece of medical evidence.^[47]  Here, the compensation judge accepted Dr. Van Nostrand’s causation opinions and properly analyzed this claim as a Gillette injury.^[48]  The weight given Dr. Van Nostrand’s medical opinions, together with all the admissible evidence,^[49] was adequate to establish that the thumb and finger conditions were caused by or “substantially contributed to or aggravated by” the cumulative finger movements, which were frequent and repetitive in the performance of the employee’s day-to-day work activities.  The findings made by the compensation judge were adequately supported by the record to conclude that the employee sustained a Gillette-type injury to her left thumb, left middle finger, and left ring finger,^[50] and we affirm the compensation judge on this issue.

The compensation judge noted the following in her memorandum:

The employer and insurer contend that the compensation judge erred as a matter of law in concluding that their notice and statute of limitations defenses were not properly raised at the hearing.  They contend that these defenses were initially presented in their answer to the employee’s claim petition^[51] and restated in written closing argument.  The employer and insurer also claim that the compensation judge did not allow opening statements at the beginning of the hearing and instructed the parties to submit their positions in written closing argument.  Given the compensation judge’s instructions, appellants maintain the issues raised were timely and fair.  We reject these arguments for the reasons stated below.

In reaching a decision, the compensation judge is subject to statutory and administrative procedural rules, including Minn. Stat. §§ 176.306 and 176.341 and Minn. R. 1420.2900.  Opening statements are not required but may be given at the request of the judge or any party in the proceeding.

At the beginning of the hearing in this matter, the compensation judge made an introductory statement summarizing the issues and stipulations agreed to by the parties, as follows:

Notice-type defenses are to be determined by the compensation judge based on the facts and evidence presented under oath and subject to cross-examination.^[53]  Closing argument is an opportunity for the parties to reiterate their positions and make recommendations based upon the evidence of record; it is not the time to present new issues for consideration.^[54]  Here, raising notice and statute of limitations defenses for determination in written closing argument is untimely.^[55]  The compensation judge’s decision to limit the issues raised by the parties at hearing was not an error of law and we affirm.