The self-insured employer appeals the compensation judge’s award of permanent partial disability benefits and medical expenses, arguing that some of the claimed benefits are not causally related to the employee’s work injuries.  The employer also argues that the judge erred by not barring a right foot injury as being claimed beyond the statute of limitations.  We affirm as modified in part and vacate in part.

On the date of the hearing, John DeNoma, the employee, was 61 years old and lived in Vadnais Heights, Minnesota.  The employee began working in the police department of the City of St. Paul, the employer, on January 21, 1971.  The employer was self-insured for workers’ compensation liability.  The employee worked as a patrol officer, a sergeant, an investigator, and a lieutenant in several different positions for the department until he retired in September 2000.

Over the years, the employee sustained several work-related injuries which required treatment.  The employer provided an overview of the employee’s work history and medical treatment history in its brief.  The employee adopted this overview, with the exception of citations to some medical records and documents which he claimed were not included in the record on appeal.  We note that some of these citations were simply incorrect exhibit numbers and that the medical records and documents were included in the exhibits submitted at the hearing.  We have relied on the overview agreed upon by the parties and the exhibits in the record for our review.

On March 14, 1976, the employee was injured in a motor vehicle accident while driving a squad car.  The employee recalled having injuries to his head, neck, upper back and lower back, right hand, and right knee.  The ambulance records dated March 14, 1976, indicated the employee sustained an injury to his upper back and neck as a result of an auto accident.  The St. Paul Ramsey Hospital record indicated the employee was treated in the emergency room for a whiplash injury to the neck, with an expected disability of three days to possibly three weeks.  The employee was off work for approximately one week.  There are no other records contained in the hearing record from 1976.

The employee testified that when he returned to work he was still having problems and that his neck, upper back, lower back, and right hand pain, discomfort and symptoms that developed after this injury never completely resolved but that his right knee pain and symptoms did improve.  The employee was able to continue working despite the ongoing pain and symptoms through use of physical therapy and home exercise, which he has performed for his neck and back conditions ever since 1976.

The employee treated with Dr. Donald Smiley at Central Orthopedics, P.A., on May 3, 1978, reporting that he had experienced pain in his neck, shoulders, and arms since the 1976 accident.  Dr. Smiley diagnosed residuals of cervical strain and recommended therapy.  Dr. Smiley opined that this was primarily a myofascial injury.  On April 3, 1979, the employee treated with Dr. Donald Lannin, also at Central Orthopedics, P.A., reporting weakness of the neck, clicking and snapping sensations on twisting motions, and neck tightness.  Dr. Lannin stated that the employee had a neck sprain and that he would not benefit from any type of therapy, and recommended the employee remain active and change positions.  The employee returned to Dr. Smiley on May 17, 1979, reporting ongoing neck pain.  In a letter dated June 4, 1979, Dr. Smiley indicated that the employee had sustained a 2.5% permanent partial disability of the spine as a whole.  On August 3, 1979, the employee treated with Dr. Lannin, reporting the same stiffness of the neck, tightness of the neck, and pulling sensation on twisting motions.  Dr. Lannin had no treatment recommendations.  The employee treated with Dr. Smiley on July 22, 1981, for ongoing complaints with his neck.  Dr. Smiley prescribed medication.

On August 6, 1981, the employee underwent a functional evaluation with Dr. Michael Kosiak.  Dr. Kosiak diagnosed neck pain, chronic, secondary to degenerative joint disease and tension neck syndrome, and opined that the employee did not require any formal treatment measures or require any restrictions on his activity.

On August 22, 1981, the employee was injured when a perpetrator assaulted him by slamming his head through a ceiling.  The employee then fell through a glass coffee table and sustained injuries to his neck, back and right hand.  The employee remained off work for several weeks following this incident and continued to have symptoms which were different from the symptoms he had prior to the assault.  The employee had symptoms in the right hand, including numbness, and felt his finger healed in a rotated fashion.  The numbness in the hand had been ongoing since the 1976 injury, but the August 1981 assault worsened this condition.  The employee testified that these symptoms have never returned to their pre-1981 assault level and have progressively worsened over the years.  The employee also testified that his low back symptoms also never returned to their pre-1981 assault level.

The employee treated with Dr. Smiley again on June 15, 1983, for complaints of neck pain.  Examination revealed a stiff neck with tenderness across the C6-7 area in the trapezius and supraspinatus area.  Dr. Smiley recommended the employee continue with physical therapy and prescribed medication.

In February 1984, the employee injured his left foot at work when he tripped on rolled-up carpet.  This injury was reported to the employer.  The employee continued to have symptoms until 2001, at which time he underwent surgery on his left foot.  The employee testified that following the surgery he had some improvement, but that he continued to have pain.

On April 17, 1985, the employee presented to Dr. Tim Rumsey, reporting occasional numbness of hands, mid-thoracic back pain radiating to the anterior chest wall, and almost daily neck discomfort with exacerbations of significant pain at times.  Dr. Rumsey diagnosed recurrent neck strain secondary to whiplash injury from a work-related incident, and recommended an orthopedic evaluation and physical therapy.

On September 17, 1985, the employee treated with Dr. Jonathan Biebl at Associated Orthopedic Consultants.  The employee reported neck pain with associated headaches and occasional pain into his arm.  Examination revealed slight diminution of his rotation right and left and significant loss of extension, crepitus in his neck, and some tightness of his parascapular and paracervical musculature.  Dr. Biebl recommended continued physical therapy for the neck and a TENS unit trial.  On January 17, 1989, the employee presented to Dr. Biebl at Summit Orthopedic Associates, P.A., for recheck of his cervical spine.  The employee reported pain in the mid-cervical/thoracic area with radiation down the right proximal arm.  Dr. Biebl assessed chronic cervical/thoracic strain with aggravation and recommended a course of physiotherapy.

On January 18, 1989, the employee was injured while skiing with the St. Paul Police ski team.  At the emergency department at St. John's Hospital, the doctor assessed a low back strain and rib contusion and prescribed medications, use of ice packs, and a heating pad.  X-rays revealed a fracture involving the anterior superior portion of the L1 vertebrae with minimal displacement of the fragment.  The employee did not receive any further treatment for the fracture and to the best of his knowledge, the bone healed, and he denied any continuing problems or symptoms as a result of this ski incident.

On August 22, 1991, the employee treated with Dr. Biebl for significant ongoing problems with his upper back and neck.  Dr. Biebl recommended an MRI of the employee's spine.  The employee underwent physical therapy at Physicians Neck and Back Clinic between August 28, 1991 and January 31, 1992.  At the time of his discharge in January 1992, the employee showed increased strength and work capacity for both the back and neck.  In a May 12, 1992, letter, Dr. Biebl opined the employee had an 18% disability of the spine with regard to his cervical spine injury.  The employer paid the employee 18% permanent partial disability that month.

The employee alleges that he sustained a right foot injury while training in May 1992, and that there is a first report of injury with a date of injury of May 27, 1992, for this incident.  The employee claims the date of injury was mistakenly reported as June 7, 1992.  At hearing, the employer asserted the statute of limitations barred the employee's claims regarding an alleged right foot injury of June 7, 1992.  The employer argued that the employee did not provide any testimony regarding the alleged right foot injury and that there is no first report of injury for that injury.  The employee treated with Dr. Biebl on June 9, 1992, and reported injuring his foot while training.  Dr. Biebl diagnosed tenosynovitis and a spur over the first metatarsal joint, prescribed medication, and provided some padding to protect the injured area of the foot.

The employee presented to Dr. Biebl on September 22, 1992, for evaluation of neck pain.  Dr. Biebl recommended a short course of physical therapy.  Between September 22 and November 25, 1992, the employee underwent physical therapy at Spectrum Therapy Centers.  At his initial visit, the employee described sudden onset of right-sided cervical and interscapular pain, constant headache, and constant cervical pain.  The employee's condition improved and he continued with a home exercise program and stretching.

In March 1993, the employee saw Dr. Biebl and reported back spasms after taking an accident reconstruction class.  The employee had developed significant interscapular pain radiating to his neck.  Examination revealed right paraspinal musculature spasm from the lumbar spine up to the interscapular area.  Dr. Biebl recommended physical therapy and prescribed medication.  Between April 1 and May 7, 1993, the employee underwent 14 physical therapy sessions at Spectrum Therapy Centers.  At the time of his final treatment, the employee reported some improvement.

The employee presented to Dr. Biebl on March 7, 1994, for follow up of his back.  The employee had a palpable spasm in the right paraspinal musculature from the upper lumbar to the cervical area, tenderness in both levator rhombi and scapular levators, and reduced range of motion in his neck and back.  The record appears to be missing medical records from the employee’s physical therapy treatment and his treatment with Dr. Biebl from March 1994 through May 1998.  The employee asserts that he had physical therapy from May to June 1994, from February to March 1995, and for three sessions in May 1995, and that he also continued treating with Dr. Biebl for neck pain during that time.

On November 10, 1995, the employee underwent a CT scan of the cervical spine at St. Paul Radiology, which indicated minimal midline bulging at C4-5, and no evidence of a herniated disc.  The scan could not exclude a herniated disc at C7-T1.

On January 25, 1996, the employee was evaluated by Dr. Mark Agre at United Hospital's Rehabilitation Clinic.  Dr. Agre assessed chronic cervical thoracic pain for over 20 years and recommended continued physical therapy, a cervical pillow, and an aerobic program.

On March 12, 1997, the employee was treated in an emergency room for a severe pain on the right side of his head and received an occipital nerve injection.  He followed up with Dr. Biebl on April 7, 1997, reporting persistent neck pain and shooting pain into his arms.  Dr. Biebl recommended an MRI.  The April 10, 1997, cervical spine MRI indicated some changes of cervical spondylosis, most prominent at C6-7 where interbody and uncinate spurring was asymmetrically prominent posterolaterally on the left, no evidence for disc protrusion, central canal stenosis or high grade bony foraminal encroachment in the cervical region, and no evident change compared with CT scan of November 10, 1995.  On May 16, 1997, Dr. Biebl reviewed the MRI scan and assessed multiple level degenerative disc disease from T5 to T9.  Dr. Biebl recommended physical therapy and renewed the employee's medications.

On December 29, 1997, the employee was evaluated by Dr. Kent Wilson for increasing difficulty with hearing.  He told the doctor that he had a strong noise exposure history working in the police department, since hearing protection was not available or required on the pistol range when he started working for the employer, but that later he wore hearing protection.  The employee had decreased hearing in both ears since 1993, and at this time he had a 6% hearing loss in the right ear and 9% in the left.  Dr. Wilson encouraged the employee to use ear plugs, consider amplification, and to have routine audiograms.

In January 1998, the employee testified that he was injured at work when an individual attacked him.  The employee sustained multiple kicks and punches to the head, and reported stiffness in his neck and upper back.  He was treated at United Hospital for contusions and abrasions.  The employee was off work for a period of time.

The employee treated with Dr. Stephen Wagner at United Pain Center in 1998, including trigger point injections, nerve blocks, or epidural steroid injections.  Between May 8 and September 29, 1998, the employee underwent 31 physical therapy sessions at Spectrum Therapy Centers for complaints of neck and back pain, inability to focus at times due to pain, irritability, poor sleep patterns, difficulty putting on shoes and socks, and inability to get comfortable.  The employee indicated he was able to self-manage his symptoms with his home program for a day and a half at a tolerable level following therapy treatments.

The employee returned to Dr. Biebl on June 16, 1998, for follow up, reporting numbness and tingling in his right foot medial border and great toe for the past six to seven weeks and back pain.  Examination revealed tenderness over the sciatic notch and positive straight leg raising at 80 degrees.  Dr. Biebl assessed right L5 or possible L4 radiculopathy. Dr. Biebl recommended an MRI.  A July 23, 1998, lumbar spine MRI indicated small central disc protrusion at L4-5 with associated slight interspace narrowing, mild to moderate loss of disc hydration, partial annular tear posteriorly at the lumbosacral interspace with central annular bulging, and mild annular bulging slightly more prominent on the right at L3-4 without neural impingement.  On August 5, 1998, Dr. Biebl read the MRI as indicating a significant neural impingement at L4-5 on the right side and recommended a selective nerve root injection, increased physiotherapy and an EMG, and also that the employee use a light-weight gun belt.

On August 21, 1998, the employee was evaluated by Dr. Richard Foreman at Neurological Associates.  He reported experiencing periodic pain and numbness down the right leg towards the medial portion of the foot and at the first and second toes, and off and on low back pain.  Dr. Foreman read the employee’s EMG as normal and found no focal neurologic impairments.

The employee returned to Dr. Biebl on October 16, 1998, for follow up, reporting mid-lumbar, mid-back, neck, leg, and left arm pain. Dr. Biebl recommended continued physical therapy and referred him to Dr. Paul Hartleben for surgical consultation.  After examination on November 16, 1998, and review of MRI images, Dr. Hartleben diagnosed multiple level cervical and lumbar degenerative disc disease with chronic history of regional pain and recent onset of right leg radiculopathy and most likely a large spur or acute disc herniation.  Dr. Hartleben recommended a CT myelogram and consideration of a transforaminal nerve block and an epidural steroid injection.

On December 10, 1998, the employee was evaluated by Dr. P. Thienprasit at Millennium Neurosurgery, P.A.  Dr. Thienprasit suggested consideration of an anterior cervical fusion at the C6-7 level and possibly an anterior lumbar interbody fusion at the L4-5 level.  The employee underwent a lumbar myelogram on December 29, 1998, at United Hospital.  The myelogram suggested a right lateral disc protrusion at L4-5 with non-filling of the root sleeve.  A lumbar CT scan revealed moderate sized disc protrusion with an extruded fragment at the L4-5 interspace level with the extruded fragment extending into the lateral recess of L5 on the right, abutting and displacing the traversing right L5 nerve root, which corresponded to the employee's clinical symptoms.  Dr. Hartleben reviewed the CT scan and opined that the employee was a candidate for a focal laminotomy and decompression procedure.  He referred the employee for a transforaminal L5 root epidural or a very focal L4-5 epidural.

On January 21, 1999, Dr. Thienprasit recommended a hemilaminectomy at the L4-5 level, and indicated that the employee was a candidate for an interbody fusion if his back pain did not improve after the laminectomy.  Dr. Thienprasit, in correspondence to the employer on January 25, 1999, also stated it was his opinion that the employee's disc herniation at L4-5 was the result of the employee's March 1976 work-related motor vehicle accident.

The employee treated with Dr. Biebl on April 26, 1999, for evaluation, reporting some improvement in symptoms since he started wearing plain clothes at work and stopped wearing a gun belt.  He also reported that chiropractic treatment, which started in September 1998, seemed to be working, but that he still had mid back, cervical spine and interscapular pain.  Dr. Biebl prescribed medication and indicated that the employee was not capable of working as a watch commander on tour or wearing his gun belt.

On July 23, 1999, the employee presented to Allina Medical Clinic for an exacerbation of his neck.  He had more acute pain and felt nauseated with discomfort any time he tried to sit up or move his neck.  Dr. Richard Glasgow assessed exacerbation of underlying chronic neck pain and administered a Demerol shot, and recommended the employee follow up with the pain clinic.

The employee treated with Dr. Hartleben on August 10, 1999, for follow up of his cervical and lumbar condition.  The employee stated that chiropractic treatment had reduced his nerve pain down the right leg but that he had low back and neck pain with radiating skull symptoms associated with headaches.  Dr. Hartleben did not advise an aggressive surgical approach for either cervical or lumbar conditions at that time, and recommended a repeat course of physical therapy focusing on the neck.

In December 1999, the employee was involved in a work-related motor vehicle accident and experienced a recurrence of his neck and back complaints as a result of this incident.  The employee treated with Dr. Steven Bergeson at Allina Medical Clinic on January 18, 2000, for upper neck and back pain, low back pain, and pain down his arms.  Dr. Bergeson assessed chronic cervical and upper back pain and recommended he remain off of work until he followed up at the United Pain Clinic, and also recommended treatment with a physiatrist or at Physicians Neck and Back Clinic.  Between February 3 and June 5, 2000, the employee underwent 31 physical therapy sessions at Physicians Neck and Back Clinic.  At the time of his discharge from physical therapy in June 2000, the employee continued to make steady objective gains.

The employee retired from his job with the police department in September 2000, claiming that his low back, upper back, neck, right arm and right leg pain would not allow him to continue working as a police officer.

The employee testified that he had a hearing loss at the time of his retirement.  He did not wear hearing aids then, but had limited hearing with difficulty in certain sound ranges.  The employee has also continued to treat for his neck and back since retiring, including medication and injections at United Pain Center and an exercise program at the Courage Center.  For about five months, the employee was able to work part time for Ramsey County at home as a consultant regarding training of dispatchers and operators.  The employee also worked a temporary job as a chauffeur for a few days, involving about four hours of driving.  The employee denied having any other employment since his retirement.

The employee has continued to receive medical treatment.  He treated with Dr. Biebl for lower back and neck pain and right arm symptoms and with Dr. Steven Kiester at Aspen Medical Group for foot pain.  On October 26, 2001, the employee underwent enclavement osteotomy of the left foot for degenerative joint disease of the first metatarsophalangeal joint in the left foot and hallux limitus, performed by Dr. Kiester at United Hospital.  The employee presented to Dr. Biebl on October 30, 2001, for follow up of his right mid foot.  X-rays showed some mild degenerative changes at the keystone joint of the second metatarsal tarsal joint of the foot, but Dr. Biebl stated it was not a flagrant change and recommended no further treatment.

The employee underwent a lumbosacral MRI at St. Paul Radiology on December 11, 2001.  The MRI revealed no significant change when compared to the July 23, 1998, study.  The employee treated with Dr. Hartleben on February 8, 2002, for follow up of his chronic regional neck and low back pain.  Dr. Hartleben recommended a right-sided L4-5 transforaminal injection.

On February 27, 2002, the employee was evaluated by Dr. Richard Gregory at Neurosurgery Associates for back pain.  An MRI revealed lateral recess stenosis at L4-5, possibly causing right L5 root compression. Dr. Gregory assessed lateral recess stenosis at L4-5 on the right and recommended lumbar spine films, a neurology consultation, and an EMG of the right leg to consider a possible laminectomy.  The employee was evaluated by Dr. Richard Foreman at Neurological Associates of St. Paul on March 26, 2002.  Dr. Foreman read both a 1998 EMG and a current EMG of the right leg as normal and concluded that the employee had no specific neurologic deficits.  The employee presented to Dr. Biebl on February 7, 2003, for follow up of his neck and back symptoms.  Dr. Biebl recommended a functional capacity evaluation and a vocational assessment.

The employee treated with Dr. Manuel Pinto at Twin Cities Spine Center on May 1, 2003, complaining of low back pain radiating to the right leg, ankle, and foot, as well as thoracic and cervical pain.  Dr. Pinto assessed discogenic pain with signs of multi-level lumbar and thoracic disc degeneration and juvenile discogenic disease changes.  Dr. Pinto recommended a discography, updated MRIs, and a brace.  The employee underwent a lumbar spine MRI on May 12, 2003.  The MRI indicated multilevel degenerative lower thoracic and lumbar spondylosis.^[1]  Dr. Pinto did not have any surgical recommendations for the employee.

On October 28, 2003, the employee underwent a two-level lumbar facet nerve block at the L1 and L2 levels. The employee described 70% improvement in pain symptoms 30 minutes post injection.  A November 10, 2003, cervical spine MRI revealed multi-level degenerative disc disease of the cervical spine predominantly involving the C5-6 through C7-T1 levels with multi-level lateral spinal stenosis.  There was also a small central and left paramidline disc herniation at the C5-6 level with mild impingement on the ventral aspect of the cord.

On January 27, 2004, the employee underwent an orthopedic consultation with Dr. Michael Smith, who assessed cervical, thoracic and lumbar pain, chronic pain syndrome, and degenerative disc disease.  Dr. Smith discussed possible low back fusion.

The employee presented to Dr. Kent Wilson on February 13, 2004, for follow up regarding his hearing loss.  Dr. Wilson stated the employee had a clear documented history of noise-induced hearing loss related to his former employment as a police officer with gunfire exposure on the shooting range.

The employee presented to Dr. Biebl on July 26, 2004, for evaluation and overall check-up.  Regarding the relationship of the employee’s overall spine symptoms to his 1976 work injury, Dr. Biebl indicated that the employee injured his mid back and neck and then, while rehabilitating the mid back and neck, he threw out the low back.  Therefore, Dr. Biebl considered the employee's entire spine condition to be related to the 1976 injury.

On July 27, 2005, the employee underwent an MRI of the lumbar spine.^[2]  On August 18, 2005, the employee returned to Dr. Pinto, reporting persistent low back, right buttock, and lower extremity pain.  Dr. Pinto opined the employee had morphologically abnormal discs involving the entire lumbar spine and also into the thoracic spine, and advised the employee to continue with conservative care as long as possible and that a lumbar decompression might be a surgical option later on.

The employee returned to Dr. Biebl on September 20, 2005, for evaluation.  He stated that the employee’s neck pain stemmed from the 1976 car accident, while the low back pain stemmed from 1996, that the employee also sustained a thoracic injury in 1990, and had progressive deterioration and almost a Gillette-type injury over the course of his nearly 30 years of employment.  Dr. Biebl opined that the present symptoms and level of disease were a natural progression of the injury sustained at work.

The employee continued with occasional physical therapy and medical treatment as needed.  He returned to Dr. Pinto on September 20, 2007, for an acute flare up of low back pain over the past six weeks.  Dr. Pinto recommended proceeding with pool therapy, medication, and a brace.  The employee testified that he underwent surgery at the C6 level for right arm symptoms in October 2007.  Following surgery, the employee experienced some relief to his right arm and neck symptoms.  The employee underwent an MRI of the lumbar spine on March 5, 2009, which indicated multilevel degenerative disc disease involving all lumbar levels.^[3]  On April 30, 2009, the employee reported persistent thoracic, low back, and lower extremity pain.  Dr. Pinto discussed treatment options, including a simple laminotomy at L4-5 and L5-S1.

On October 13, 2009, the employee underwent a right C6-7 micro-foraminotomy performed by Dr. Mary Dunn at United Hospital.  Following surgery, the employee continued to follow up with Dr. Dunn and also at the United Pain Clinic, where he underwent various injection therapies for both his lumbar, thoracic, and cervical spine.

The employee was evaluated at the Institute for Low Back and Neck Care (ILBNC) on March 3, 2010, for cervical pain and right leg pain, and continued to treat at ILBNC through April 28, 2010, undergoing injections in the lumbar and cervical spine.  The employee's current low back symptoms include pain down the right leg and into his foot.  At times the employee will lose mobility in his right foot and fall.  He also has pain down the left leg and will miss the left foot too.  The employee described numbness in his right foot, heel, and toes.  The employee testified that he is on a number of medications for his pain, and that he is unable to help much around the house with chores.

The employee underwent an orthopedic consultation with Dr. Robert Wengler on November 20, 1979.  Dr. Wengler diagnosed cervical disc syndrome, the onset of which he related to the car accident of March 1976.  Dr. Wengler opined that the employee would be able to return to general duty patrol work, and estimated the employee's present difficulty represented about a 25% permanent partial impairment of function of the employee's spine.

The employee underwent an independent medical examination with Dr. Joseph Tambornino on April 28, 1999.  The employee reported his neck and upper back pain began after his 1976 accident and that he was working out and performing exercises for his neck and upper back when his lower back started bothering him about a year before this evaluation.  After an examination, history and review of the records, Dr. Tambornino diagnosed a soft tissue strain of the neck and upper back, which had healed.  Dr. Tambornino opined that the ongoing back and neck problems were no longer related to the work injury of March 14, 1976, and that the employee had reached maximum medical improvement for his neck and upper back injuries within six months following the 1976 accident and for the low back injury in the early part of 1999.  He also opined that chiropractic care was not appropriate or indicated, but that the employee's treatment to date had been reasonable and necessary, that further medical treatment was not necessary or related to the March 14, 1976, injury, and that the March 14, 1976, accident did not cause the employee to be unable to work.

On June 3, 1999, Dr. Tambornino prepared a supplemental report regarding his examination of the employee on April 28, 1999.  In his supplemental report, Dr. Tambornino opined that the employee required restrictions including:  avoiding strenuous physical labor, lifting more than 40 pounds occasionally and 20 pounds frequently, and avoiding bending, lifting, and stooping frequently.  Dr. Tambornino opined that the wear and tear of daily living and some incidents other than the 1976 motor vehicle accident were the cause of the employee's ongoing problems and not his work or the accident of March 14, 1976.  Dr. Tambornino also opined that the employee did not have objective findings that indicated he had an ongoing problem with his lower back as a result of the exercising activity a year prior.

On April 18, 2000, the employee underwent an independent medical examination with Dr. Scott O'Connor.  Dr. O'Connor diagnosed chronic neck and back pain dating back to the accident in 1976, with a temporary aggravation of the employee's preexisting condition based on the motor vehicle accident of December 1, 1999.  Dr. O'Connor opined that the employee’s medical and chiropractic treatment for the first month to six weeks following the accident was reasonable, that the employee did not require physical restrictions or limitations due to the December 1999 motor vehicle accident, and that the employee should follow the recommendations of the Physicians Neck and Back Center.

In October 2001, Dr. Biebl diagnosed the employee with degenerative disc disease of the cervical, thoracic, and lumbar spine with myofascial pain, herniated disc at L4-5 with radiculopathy, degenerative arthrosis, left great toe, right shoulder tendinitis, and right foot pain.  Dr. Biebl indicated that the employee underwent a scan in 1991 for his low back, “but it was really after the assault in 1998 that the symptoms seemed to accelerate.”^[4]  Dr. Biebl opined the employee had a permanency rating of 9% for the cervical spine and that the employee did not have a ratable disability for the thoracic spine.  Dr. Biebl provided a 4% permanency rating for the employee's left great toe under Minn. R. 5223.0170, subps. 9.A and B.  He also opined that the employee was disabled from any gainful employment of more than sedentary duty with frequent change of position and freedom to move and stretch, and that future medical treatment could include a decompressive laminectomy for the L4-5 disc and possible cervical fusion if his symptoms continued to worsen and a fusion arthrodesis of his left great toe.  Dr. Biebl further opined that the employee's lumbar spine condition was the result of a Gillette-type injury, that there was an initial injury for the employee's neck and thoracic spine, and that the employee's employment was a substantial contributing cause of the employee’s lumbar spine degeneration.

Dr. Kiester issued a report dated August 1, 2004, addressing the status of the employee's foot problems.  The diagnosis for the left foot was severe degenerative arthritis of the left great toe.  The employee had a joint clean up surgery with osteotomy of the first metatarsophaiangeal joint, but continued to have pain and disability.  Dr. Kiester opined that the employee's work and continued duties as a police officer contributed to his worsened condition, ultimately resulting in surgical correction.  Dr. Kiester rated the left foot and toe on the 1982 disability schedules, which were concerned with loss of function and rated in terms of weeks of disability.  Dr. Kiester admitted the employee did not lose a portion of his foot or toe, but did lose function in the left great toe joint.  The actual disability would be a percentage of total loss.  Dr. Kiester rated that based on 40% of the total loss of the great toe joint, and rated the left foot as 10% total loss.  Dr. Kiester rated the employee’s right foot at 1% for ongoing problems in the dorsum, even though the employee did not have surgery or significant treatment on this foot.

On August 30, 2005, Dr. Kent Wilson issued a report addressing the employee's permanency related to his hearing loss.  Dr. Wilson reviewed the employee's audiograms from 2000 and 2004 and assigned a 2% permanency rating for the 2000 audiogram and 8% for the 2004 audiogram.

Dr. Biebl provided another report dated August 15, 2006, addressing the employee's ability to work and his medical treatment.  Dr. Biebl diagnosed an L4-5 disc herniation with multilevel lumbar disc degeneration, cervical disc degeneration, arthritis of the right big toe, tendonitis of the right shoulder, and chronic pain syndrome and opined that the employee was completely disabled and could not perform his duties as a police officer.  Regarding a Gillette-type injury, Dr. Biebl opined the employee had sustained multiple documented injuries while at work and believed that day-to-day traumas also aggravated the underlying condition.  Dr. Biebl opined that the employee's employment, therefore, was a substantial contributing cause to the degeneration.  Dr. Biebl provided restrictions of 10 pounds lifting maximum, change of position, no prolonged standing or sitting, and no working in a stooped position.

The employee underwent an independent medical examination with Dr. Nolan Segal on July 12, 2006.  After an examination, history and review of extensive radiologic studies and medical records dating back to March 14, 1976, Dr. Segal opined the employee sustained cervical and thoracic strains as a result of the 1976 work-related injury.  Dr. Segal also diagnosed Scheuermann's juvenile disc disease affecting the employee's thoracic and lumbar spine and multilevel degenerative disease of the cervical and lumbar spine.  Dr. Segal opined the employee reached maximum medical improvement regarding all of the alleged musculoskeletal conditions as of the date of his evaluation.  Based upon the examination of the employee and his limited range of motion in the cervical spine, Dr. Segal opined the employee sustained a 5% disability to the spine relative to the 1976 injury.  Dr. Segal opined the employee did not have any other work-related permanent partial disability as a result of any alleged work injuries or as a result of his employment activities.

Dr. Segal also was of the opinion that none of the chiropractic care rendered was reasonable or necessary and none of the employee's lumbar spine or lower extremity treatment was reasonable or necessary relative to his work activities or alleged work injuries, but that some limited passive therapy with institution of an active home exercise program would be appropriate.  Dr. Segal apportioned 10% of the cervical spine treatment to the 1976 injury.  Dr. Segal opined the employee did not require any further treatment from any health care providers to cure and/or relieve any work-related abnormalities.  Dr. Segal opined the employee was not a surgical candidate for any of his diagnosed musculoskeletal conditions and advised against any ongoing chiropractic adjustments to the cervical, thoracic or lumbar spine.

Dr. Biebl issued another report in March 2007, and opined that the L1 compression fracture resulted in a 4% permanency rating, that the multiple levels of degenerative disc disease resulted in a 10% rating, and that the herniation at L4-5 resulted in a 9% rating.  Overall, Dr. Biebl opined the employee was totally disabled.

The employee underwent another independent medical examination with Dr. Segal on February 15, 2010.  Dr. Segal opined that the employee had juvenile disc disease with multilevel degenerative disease of the cervical, thoracic, and lumbar spines and required permanent restrictions including no lifting or carrying over 30 pounds, avoidance of repetitive bending, lifting and twisting, the ability to change positions between sitting, standing and walking periodically, and no overhead work or use of his neck in awkward positions, but that the restrictions were not related to the 1976 work injury.  Dr. Segal opined there was no evidence that the employee was unable to continue working from an objective musculoskeletal standpoint between March 14, 1976, and the present.  Dr. Segal found no evidence the employee sustained structural injuries to his musculoskeletal system as a result of the apparent work injuries, with the exception of possibly some hallux rigidus in his left great toe, which did not require any particular restrictions.  Dr. Segal opined the need for the employee's restrictions was due to his underlying degenerative condition.  Dr. Segal again opined the employee reached maximum medical improvement by July 12, 2006, and that the employee qualified for a 10% permanent partial disability rating for his cervical spine.  Dr. Segal noted all the treatment and expenses incurred from the time of the 2006 independent medical examination up to and including the current time were due to the employee's degenerative conditions and not due to his employment-related injuries.

The employee underwent an independent medical examination with Dr. Barry Kimberley on November 18, 2011.  After an examination, history and review of the records, Dr. Kimberley opined that the alleged history of noise exposure at work along with the medical records allowed him to conclude that the work-related noise exposure was a significant contributing factor in the employee's bilateral hearing loss.  Dr. Kimberley assessed a 2% permanent partial disability rating related to the hearing loss in 2000.  Dr. Kimberley opined that the additional 6% permanency, occurring between 2000 and 2004, was unrelated to the employee's work with the employer since the employee had retired from the employer in 2000 and was no longer experiencing work-related noise exposure.

On January 31, 2006, the employee filed a claim petition alleging a March 14, 1976, injury to the neck and back, a 1984 left foot injury, a 1992 right foot injury, and a 2000 Gillette injury for hearing loss.  The employee claimed additional permanent partial disability for his cervical spine, 10% permanent partial disability for his left foot, 1% permanent partial disability for his right foot, and 10% permanent partial disability for his hearing loss.  He also claimed medical expenses and rehabilitation benefits.  The employer denied the claim.

The employee filed an amended claim petition on August 24, 2009, for essentially the same claims plus permanent total disability benefits from September 2000.  The employer, in response, admitted a 2% permanent partial disability rating for the employee’s hearing loss but denied any additional hearing loss claim.  A hearing was held on January 25, 2012.  The compensation judge awarded permanent total disability benefits, medical expenses, and permanent partial disability for the employee’s cervical spine, his left foot, his right foot, and his hearing loss.  The self-insured employer appeals.

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.^[5]  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.^[6]  Fact findings are clearly erroneous if the reviewing court, looking at the entire evidence, is left with a definite and firm conviction that a mistake has been committed.^[7]  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.”^[8]  A decision which rests upon the application of a statute or rule to essentially undisputed facts generally involves a question of law which the Workers' Compensation Court of Appeals may consider de novo.^[9]

The employer presents seven issues for determination on appeal.  First, whether the employee sustained a permanent injury to the lumbar spine as a result of a March 14, 1976, work injury; second, whether the employee sustained 25% permanent partial disability of the cervical spine as a result of a March 14, 1976, work injury; third, whether the employee sustained a permanent injury to his left foot as a result of the February 23, 1984, injury resulting in a 10% permanent partial disability; fourth, whether the employee sustained 1% permanent partial disability of the right foot due to a June 7, 1992, injury; fifth, whether the employee sustained additional permanent partial disability for hearing loss beyond the 2% admitted; sixth, whether the intervention claims for medical treatment were reasonable, necessary and causally related to compensable work injuries; and seventh, whether the judge erred by failing to apply the statute of limitations to bar the employee’s claims related to a June 7, 1992, right foot injury.  The employer did not appeal the award of permanent total disability benefits.

The employer argues that substantial evidence does not support the compensation judge’s finding that the employee sustained a permanent injury to his lumbar spine as a result of the 1976 accident.  The employer claims that the employee only injured his neck and upper back in that accident and lists numerous medical records where the employee complained of neck and upper back symptoms after the accident but not low back symptoms and also where he reported to medical providers that he injured his neck and upper back in the accident and that he experienced lower back symptoms later.  The employer contends that the evidence shows that the employee sustained a Gillette-type^[10] injury to the low back rather than a specific injury related to the 1976 accident.  We are not persuaded.

The employee testified that he injured his low back in the 1976 accident and that he never fully recovered after that accident.  He also testified that his low back condition worsened as a result of various work incidents over the years, after an aggravation while rehabilitating his neck, and from wearing his gun belt at work.  The record contains expert medical opinions, including those of Dr. Biebl, Dr. O’Conner, and Dr. Thienprasit, which support the compensation judge’s finding that the employee’s lower back was injured in the 1976 accident.  Although the record contains conflicting medical opinions on the extent of the employee’s injuries after the 1976 accident, it is the compensation judge's responsibility, as trier of fact, to resolve conflicts in expert testimony.^[11]  Substantial evidence supports the compensation judge’s finding that the employee sustained a permanent injury to his lumbar spine as a result of the 1976 accident, and we affirm.

The employer contends that substantial evidence does not support the compensation judge’s finding of a 25% permanent partial disability rating for the employee’s cervical spine.  The compensation judge relied on Dr. Wengler’s opinion for this rating.  The employer contends that Dr. Wengler lacked foundation for his opinion.  The competency of a medical expert to provide an expert opinion depends upon both the extent of the expert’s scientific knowledge and the expert’s practical experience with the matter that is the subject of the opinion.^[12]  Dr. Wengler obtained a history from the employee, reviewed the relevant medical records, and performed a physical examination.  As a general rule, this level of knowledge is sufficient to afford foundation for the opinion of a medical expert.^[13]  We conclude that Dr. Wengler had adequate foundation to render a competent opinion, and that substantial evidence supports the compensation judge’s finding regarding the employee’s cervical spine permanent partial disability.

The employer also contends that substantial evidence does not support the compensation judge’s finding that the employee sustained a permanent left foot injury and a 10% permanent partial disability rating for that injury.  The employer argues that Dr. Kiester found that the employee sustained a Gillette-type injury to his left foot, not a specific injury.  We note that Dr. Kiester’s report does not state that the employee sustained a Gillette-type injury, but that he injured his left foot in 1984 which worsened over the years.  He had surgery on the foot in 2001, but still had pain and disability after the surgery.  Substantial evidence supports the compensation judge’s finding that the employee sustained a permanent injury to his left foot.

The finding of permanent partial disability to the left foot is one of “ultimate fact” for the compensation judge, based on the judge’s interpretation of the medical evidence.^[14]  The compensation judge relied on Dr. Kiester’s opinion that the employee had sustained a 40% loss of the great toe joint under the 1982 schedule, which he would rate as a 10% loss of the left foot.  Based on Dr. Segal’s report, the employer argues that under Minn. R. 5223.0530, subp. 3.A., the employee is not entitled to any permanent partial disability for his toe since he had no ankylosis of the great toe, which is required under that rule.  We note that Minn. R. 5223.0530 did not go into effect until 1993.  The employee testified that he was injured in February 1984, which was after the temporary permanent partial disability schedules went into effect on January 1, 1984.  That schedule contains ratings for toes with complete ankylosis.^[15]  The employee does not have ankylosis.  The compensation judge could reasonably conclude that there is no rating for the employee’s condition in the appropriate schedule.

Where a non-scheduled injury falls outside the permanent disability schedules, there is no requirement that the injury meet the specific requirements of any given category.^[16]  Permanent partial disability for a condition not rated by the disability schedules may be rated for functional loss, as stated by the Minnesota Supreme Court in Weber v. City of Inver Grove Heights.^[17]  Dr. Kiester reported that the employee had loss of function after his left foot surgery and opined that the employee had sustained a 10% loss of the left foot.  The employee continued to treat for his left foot and underwent surgery in 2001, but continued to have pain and disability, as reported by Dr. Kiester.  Substantial evidence supports the compensation judge’s finding that the employee had sustained a 10% permanent partial disability for his left foot, and we affirm.

The compensation judge also awarded a 1% permanent partial disability rating for the employee’s right foot.  The employee claimed that he injured his right foot while training in 1992.  The employer argues that this claim should be barred by the statute of limitations since there is no first report of injury for the alleged injury.^[18]  In his brief, the employee cites a first report of injury for the right foot, but that report is not included in the record.  There is a medical record indicating that the employee was treated for this injury, but there is no indication in the record that the employer was notified of this injury until the employee’s claim petition in 2006.  We therefore vacate the compensation judge’s award of permanent partial disability for the employee’s right foot and any medical expenses awarded relating to this injury.

The compensation judge awarded the employee 10% permanent partial disability for his hearing loss based on Dr. Wilson’s report indicating a 2% loss in 2000 and an 8% loss in 2004.  The employer admits a 2% permanent partial disability rating for the 2% loss.  The employee concedes that the ratings were cumulative and claims that 8% permanent partial disability represents the employee’s total hearing loss.  The employer claims that substantial evidence does not support an award of 8% permanent partial disability, citing Dr. Kimberly’s opinion that the additional 6% hearing loss from 2000 to 2004 cannot be related to the employee’s work activities since he was not working for the employer at that time.

Dr. Wilson’s records indicate that the employee’s hearing loss has progressively worsened since 1997.  The judge relied on Dr. Wilson’s opinion that the employee had a history of noise-induced hearing loss that was causally related to his work for the employer.  The compensation judge could reasonably conclude that the employee’s exposure to noise while he was working continued to contribute to his progressive hearing loss after he retired.  We affirm the compensation judge’s award of permanent partial disability for the employee’s hearing loss, modified to 8% permanent partial disability, less the 1% rating which the employer already paid to the employee.

The employer also argues that the compensation judge awarded the intervenors medical expenses which were not related to the employee’s work injuries, based on arguments that some treatment was not related to permanent conditions resulting from work injuries.  Other than the right foot injury, we have affirmed the compensation judge’s findings regarding the employee’s injuries.  We therefore affirm the compensation judge’s award of medical expenses other than those related to the employee’s right foot injury, which are vacated.