JOAN R. WITRY, Employee/Appellant, v. SACRED HEART CHURCH, SELF-INSURED, Employer, and BLUE CROSS/BLUE SHIELD OF MINN., MEDICARE, and MEDICA HEALTH PLANS/INGENIX, Intervenors.
WORKERS’ COMPENSATION COURT OF APPEALS
AUGUST 24, 2009
CAUSATION – TEMPORARY AGGRAVATION. Substantial evidence, including medical records and expert medical opinion, supports the compensation judge’s determination that the employee’s 2002 and 2005 work injuries were temporary aggravations to her pre-existing low back condition and did not contribute to her subsequent low back surgery or to an alleged consequential hip injury.
Determined by: Stofferahn, J., Wilson, J., and Pederson, J.
Compensation Judge: Catherine A. Dallner
Attorneys: John J. Horvei, Shoreview, MN, for the Appellant. Edward Q. Cassidy and Lori-Ann C. Jones, Fredrikson & Byron, Minneapolis, MN, for the Respondent.
DAVID A. STOFFERAHN, Judge
The employee appeals from the compensation judge’s determination that her work injuries on October 17, 2002, and March 30, 2005, were temporary in nature and did not contribute to her need for fusion surgery at L2-3 in 2005 or to a fall on January 3, 2006, resulting in a left hip injury. We affirm.
The employee, Joan Witry, was born in 1934 and is presently 75 years of age. After graduating from high school in 1952, the employee worked for about two years in the bookkeeping department at the Minneapolis Gas Company. She was at home raising her children from about 1954 to 1959, but did some sporadic part-time work as a supermarket cashier. In about June 1959, the employee returned to regular part-time employment, working both as a cashier and as an assistant to the bookkeeper for a small supermarket/food wholesaler business. From 1962 to 1972, she worked full-time as the business manager for this company, performing bookkeeping. When this job ended in 1972, she tried working as a realtor, but gave up that line of work in 1973.
She returned to school in 1974 at the University of Minnesota where she completed a two-year program in chemical dependency counseling. She then began working at Golden Valley Health Center as a counselor, eventually advancing to the position of assistant program director for the health center’s chemical dependency program. The employee left this job after she received an offer of employment as the program director of a new alcoholism treatment unit being opened at the Rosedale Community Hospital in Sacramento, California. After two years in that position, the employee accepted a one-year position assisting another Sacramento hospital in setting up its own program.
The employee then returned to Minnesota, where she partnered with another woman in setting up a residential treatment program for women. She continued working with that program for two years, but in 1984 sold her interest in the partnership and moved to Edina. In Edina, the employee received pastoral training to become employed as a Stephen minister with Our Lady of Grace Catholic Parish. Her duties in this ministry involved visiting homebound, hospitalized or newly widowed elderly parishioners to provide spiritual and emotional support. In June 1992, the employee began working in the same capacity for the employer, Sacred Heart Parish in Robbinsdale. In this job, she was also responsible for organizing bimonthly senior dinners at the church, for supervising senior craft-making activities including a semi-annual craft show, and for conducting a bible study program. Slightly over half of the employee’s work was done at the church, with the remainder being done at hospitals, hospices, nursing homes and parishioners’ houses.
The employee has a long history of back problems. Medical records in evidence reveal that she was admitted to St. Mary’s Hospital in Minneapolis in May 1975 for an acute exacerbation of low back pain. Straight leg raising was positive bilaterally and slight narrowing was apparent on x-ray studies at the L5-S1 level. The employee reported that she had a history of chronic low back pain since 1966. She was diagnosed with degenerative disc disease and treated with traction and physical therapy. After her acute symptoms had gradually resolved, she was released from the hospital with directions to use a lumbosacral corset and to perform home exercises.
Over the following decade the employee was also diagnosed with degenerative arthritis in both hips and knees, accompanied with osteoporosis. In May 1994, the employee was seen at Northwest Bone and Joint Associates (“Northwest”) for bilateral knee and hip pain. She reported having had bilateral knee and hip pain for several years, as well as back pain, recently accompanied with radicular pain in the left leg. On June 10, 1994, she underwent a total left hip replacement.
In follow up appointments after the surgery, the employee reported that her left leg was now a bit longer than the right, and that she was concerned this would worsen her back problems. In a chart note dated September 14, 1994, her doctor at Northwest also recorded that the employee “has had a back fusion in the past.” The doctor may have misunderstood the employee’s history, as no mention of fusion surgery performed prior to 1994 appears elsewhere in the medical records put into evidence. The employee decided to go ahead with a second hip replacement surgery, on the right. This procedure was performed on October 23, 1994.
On November 16, 1995, the employee returned to Northwest and reported increased back pain after prolonged standing. She was given a prescription for a back brace. When next seen there, on April 25, 1996, the employee noted having some left shoulder problems. She also reported intermittent sciatic nerve pain in the left leg when sitting. On examination, her low back had about 50 percent of normal motion. She was diagnosed with tendinitis and bursitis of the left shoulder and with a lumbar disc syndrome with radicular symptoms into the left lower extremity. The employee again returned to Northwest on July 25, 1996, for both her shoulder and left leg problems. Her ongoing lumbar disc syndrome was thought to be “seemingly worse.” She reported that she recently had experienced difficulty moving her left arm and left leg on awakening; her doctor speculated that this might be due to a positional type of paresthesia. The employee was continued on nonsteroidal anti-inflammatory medication.
The employee sought treatment at Northwest for hip pain in 1997; however, her prosthesis in the hips appeared sound, without evidence of loosening. On October 5, 1998, she returned complaining of low back pain radiating into her buttocks, along with numbness into her legs and feet, intermittent on the right and occasional on the left. Lumbar x-rays showed Grade I spondylosis at L4 on L5 and narrowing of the L5-S1 disc space. An MRI scan was recommended. The MRI was performed on October 6, 1998, and showed a moderate central canal stenosis at L4-5 due to spondylolisthesis, a bulky facet, and ligamentum flavum hypertrophy. There was mild multi-factorial central canal stenosis at L2-3 and L3-4, and a bilateral spondylolysis at L4. The employee was provided with a back brace and referred for a back stabilization program at the Institute for Athletic Medicine.
An initial evaluation was performed at the Institute for Athletic Medicine on October 26, 1998. The employee reported more than 15 years of back pain, which had slowly worsened to the point that it “feels like it is going to explode.” Her symptoms included central low back pain and occasional left leg pain, which the employee indicated prevented her from walking more than one block or standing more than 15 minutes, prevented vacuuming or scrubbing floors, and made it difficult for her to get up from the floor. Her lumbar range of motion was within normal limits and she did not report pain during ROM testing. The assessing therapist recommended a treatment plan consisting of three sessions involving progressive strengthening for back stabilization, and training in posture and body mechanics. At the end of the three sessions, the employee reported that she had perceived no significant improvement. She was discharged with the recommendation that she perform a program of home exercises and that she obtain a medical reevaluation from her physician for additional treatment recommendations.
Early in January 2000, the employee was seen at Northwest (now renamed “Northwest Orthopedic Surgeons”) for left knee pain, and was referred for physical therapy. She returned on January 28, 2000, to Dr. Daniel Borgen at Northwest, complaining that the physical therapy made her leg hurt and caused radiating pain down to her foot, but that it now seemed to be improving. Dr. Borgen thought that the employee had in fact had an episode of sciatica due to her spinal stenosis. He advised the employee to wait and see if the improvement she was seeing continued.
The employee returned to Dr. Borgen on February 11, 2000, for a follow up appointment. She told him that the leg pain was now persistent and seemed to be worsening. Dr. Borgen referred the employee for a lumbar MRI. The MRI was performed on February 14, 2000, and compared with the prior MRI done in 1998. It showed slight worsening of the L3-4 central canal stenosis, with the canal opening reduced to less than one centimeter. The employee was then seen for evaluation of the possibility of surgery by Dr. Paul J. Crowe at Northwest. Dr. Crowe thought a fusion might be required. The employee was uncertain how to proceed. Dr. Crowe recommended that the employee undergo an epidural steroid injection and obtain a second surgical opinion.
The employee made an appointment with Dr. David Holte at Orthopedic Consultants on the suggestion of a friend who was one of the doctor’s patients. Dr. Holte saw the employee on February 29, 2000, and also reviewed her MRI scan. She told him that while she had experienced back problems for more than 20 years, she had first experienced left leg pain after recent physical therapy for her knee. She was now having a burning sensation in her low back accompanied by sharp pain down the entire left leg and numbness and tingling in both calves and the toes of both feet. The doctor diagnosed severe spinal stenosis at L3-4 and L4-5, worse at L3-4, with pseudoclaudication and degenerative spondylolisthesis at L4-5. He suggested that the employee keep an existing appointment for an epidural injection, but return if that did not bring relief. He recorded the opinion, however, that the employee would likely need surgery in the form of a decompression and fusion.
The employee tried epidural steroid injections on March 6 and April 27, 2000, but they provided only brief relief. On May 31, 2000, she underwent surgery in the form of posterior fusion from L3 to L5 with bilateral decompression at L3-4 and L4-5 and instrumentation with screw fixation at L3, L4 and L5. Following her surgery, the employee began to use a cane for ambulation.
The employee was seen by Dr. Holte on June 12, 2000, and was noted to be doing well. She stated that while she continued to have a band of low back pain and some right buttock pain, the feeling of heaviness in her legs was gone. She rated her improvement at 80 percent. She was on disability status from work through July 31. On that date, she telephoned Dr. Holte’s office to state that her pre-surgical pain had returned, along with numbness in her left leg to the toes, and she was concerned about her scheduled return to work. Dr. Holte suggested that she might need to take frequent breaks and perhaps lie down if possible during her work day. He suggested she try working for the first week and follow up with him on Friday.
The employee thereafter arranged to permanently work a six hour per day schedule, with 30 hours per week, rather than the 40-hour work week she had customarily worked prior to the low back surgery.
On October 17, 2000, the employee returned to see Dr. Holte and reported that she had 100 percent improvement of her back pain. She was told to return for follow-up examination in about six months. The employee returned as scheduled on May 17, 2001. She complained of low back pain and burning on walking as little as one half block, and had tiredness in the legs similar to what she had prior to the surgery. She was also seeking an injection into her left knee, which was grinding as a result of a valgus deformity. Dr. Holte reviewed x-rays of the employee’s lumbar spine, and concluded that there was no sign of loosening in the position of her hardware. He recommended that she wait a week to see if the back and leg symptoms improved, and otherwise return for a steroid injection at the L5-S1 level.
The employee had an annual physical exam with Dr. Fabian at the North Clinic on April 24, 2001. Her history included lumbar disc syndrome with left lower extremity radiculopathy, treated by surgery in 2000. The employee told Dr. Fabian that she had continued to have leg pain since the surgery which was “at least as bad as it was, or perhaps even worse.” The employee intended to follow up for this with Dr. Holte.
The employee had an epidural injection on June 7, 2001, and noticed some improvement in the numbness in her left leg, but when seen for bilateral knee injections on June 12, 2001, still had numbness in the left foot and burning discomfort in the low back with walking more than one block. She had a second lumbar epidural injection on July 13, 2001.
Treatment records over the next six months focused on the employee’s knee problems, which continued to worsen to the point that she underwent a left total knee replacement on August 30, 2001, and a right total knee replacement on December 12, 2002.
On October 17, 2002, the employee was in charge of organizing a lunch meeting for the church office and school staff. Because the person who normally would be responsible for putting soft drinks, ice, utensils and cups on the tables was absent, the employee attempted to do this herself. She loaded a service cart with the necessary items, and then attempted to roll the cart out of the employer’s kitchen; however, the wheels of the cart became stuck in a perforated rubber floor mat. The employee tried to extricate the cart by simultaneously pushing and lifting while she was standing in a bent over position. She felt discomfort and in her back and had a sensation “like it had been squished.” The following morning, her back was painful and stiff and she had difficulty getting out of bed. The employee had apparently previously obtained a walker to help her in ambulation, but now also needed to use her walker to assist her in getting up out of bed.
The employee was seen at Orthopedic Consultants by Dr. Loren Vorlicky for a scheduled right knee injection on October 24, 2002. She told the doctor that she was now having some “upper [sic] back and abdominal pain,” worse over the last couple of weeks, and would like that evaluated along with the injection. Dr. Vorlicky found that the range of motion in the employee’s hips was symmetrical and painless, and that muscle strength and sensation was good in both lower extremities. Straight leg raising was negative, and the chart note does not indicate that any lumbar spasm or muscle tightness was noted. The employee did apparently mention low back complaints, as the doctor obtained x-rays of the lumbar spine, and also noted that “I think that her low back complaints are due to the degeneration of the motion segment above her fusion.” The employee also stated that Dr. Holte had asked her to refrain from bending, but that she had ignored that advice over the last year. Dr. Vorlicky did not provide any low back treatment other than to recommend that the employee resume her low back strengthening exercises and follow up with Dr. Holte.
On October 28, 2002, the employee telephoned Orthopedic Consultants and stated that she wanted to inform them that the lumbar spine pain she treated for on October 24 had been related to a work injury. The employee was advised to forward the workers’ compensation paperwork to the doctor’s office for them to fill out.
On November 14, 2002, the employee went to the emergency department at North Memorial Hospital for chest pain. She stated that she had tried to move a heavy cart at work on October 17, and then had severe left-sided pain in the lower chest and upper abdominal region, in a radicular band-type pattern. She related having seen an orthopedic physician who thought it was probably due to muscle strain from lifting the cart. That pain had been improving, but the employee had over the last five days begun experiencing a new type of pain around her left breast. The examining physician, Dr. Fabian, thought that the chest pain was likely due to muscle strain, but since the employee had a history of possible coronary artery disease, she was admitted for cardiac observation. She was discharged the next day with a diagnosis of probable non-cardiac chest pain.
The employee next saw Dr. Holte on January 14, 2003, for evaluation of back pain. She told the doctor that her problems had started at work on October 17 while lifting and pushing a cart with a loaded weight of 70 pounds, when she felt a pain in her back and had trouble standing up. She had continued to have back pain since then but it had diminished in severity. The employee’s “main problem” was now difficulty getting out of bed in the morning when “something makes a clunking noise in her low back and then she gets a sharp pain,” but after getting up and ambulating with the aid of a walker “it clunks into place [and] she is able to go the whole rest of the day without a significant problem.” Dr. Holte noted that he had reviewed the lumbar spine x-rays done on October 24, and that he “did not see anything on her x-rays that was worrisome.” On examination, the employee had no pain with extension or forward flexion; lateral bending was full and hip range of motion normal. The main finding was tenderness over the gluteal muscles on the left. Dr. Holte diagnosed a lumbar sprain/strain associated with lifting at work, complicated by previous fusion surgery. He recommended that the employee simply give this more time to improve, as it seemed already to have improved significantly. He suggested that, if the condition was not improved in two months, the employee could undergo manipulative therapy at the Institute for Athletic Medicine.
On March 20, 2003, the employee saw Dr. Garvey at the University of Minnesota Physicians Low Back Center for a second opinion about the pain in her lower back. The employee told Dr. Garvey that she had undergone fusion surgery in 2000, after which she had marked improvement in her lower extremity radicular symptoms, but continued to have low back pain. A few days after lifting 70 pounds on October 17, 2002, her back pain began to become more severe. The worsened pain was in the center of the lumbar back, and was mostly present during the first few minutes after getting out of bed, after which it typically would resolve and return to baseline. The employee expressed the fear that “things are settling in her back” and that “she could have further breakage, slippage or paralysis.” The employee had no back tenderness on palpation and straight leg raising was negative both in the sitting and supine positions. Dr. Garvey reviewed x-rays the employee brought with her and noted that although they showed a solid fusion, there was also significant degenerative disc disease at the L2-3 and L5-S1 levels. He opined that the employee’s back pain was originating from the degenerative changes at these levels. Dr. Garvey noted that it would require very invasive surgery using both anterior and posterior approaches to correct the problems at these levels, and recommended that she continue to live with the pain if possible.
The employee called Orthopedic Consultants on April 11, 2003, and spoke to a physician’s assistant. She stated that she had obtained a second opinion about her back and that an AP fusion had been recommended, but that she was not interested in that option. She requested that she be provided a prescription for physical therapy, as previously suggested by Dr. Holte. The physician’s assistant recorded that she would mail out the prescription. However, there is nothing in the medical records to suggest that the employee did follow through with the physical therapy.
There are some scattered mentions of her back diagnoses in medical records over the next year or so, but no significant treatment for back problems. In August 2004, the employee had a myocardial infarction and underwent left heart catheterization and a ventriculogram, with selective coronary artery angiography.
On March 30, 2005, the employee was performing her pastoral care duties for the employer and visiting two parishioners who were patients at the North Memorial Hospital, Catherine Ladvig and Helen Boisclair. At some point, Mrs. Ladvig fell asleep and the employee turned her attention to talking with Mrs. Boisclair and her husband, and with Mrs. Boisclair’s doctor, Dr. Susan Lyons. Suddenly, Mrs. Ladvig got up and went into the bathroom. The employee noticed that Mrs. Ladvig was having trouble finding the bathroom light, and went over to the door to turn it on for her. The employee testified that, just as she turned on the light, Mrs. Ladvig started to fall backwards, so the employee threw her arms around her and grabbed her under the arms to prevent her from falling. The employee called for help, but no one came. She then managed to inch over to the toilet and bend over to ease Mrs. Ladvig onto the seat. Some nurses arrived to assist Mrs. Ladvig and the employee then returned to the discussion with the Boisclair family and their doctor. About 20 minutes later, when the employee was going along the hospital corridor to leave, she noticed a pain in her back and down the side of her left leg.
The employee went home and was seen the following day at Orthopedic Consultants by Dr. Moser. Lumbar x-rays showed a solid fusion with no evidence of fracture, dislocation or subluxation. Examination findings suggested an absence of disc pathology. Dr. Moser diagnosed piriformis syndrome with mild sciatica down the left leg. He prescribed prednisone and recommended physical therapy to assist in strengthening around the employee’s pelvic girdle.
At the initial physical therapy evaluation on April 6, 2005, the employee reported that her symptoms included left leg cramping at night, left buttock pain, and occasional left leg numbness to the foot. She had difficulty sitting more than one hour at a time or standing for more than 10 minutes. She was given three physical therapy sessions with progressive strengthening and stretching exercises, manual therapy, and instruction in home exercise. On April 11, 2005, the employee was noted to now walk briskly without obvious discomfort; she understood her exercises and felt she could self manage. The employee was discharged from physical therapy.
The employee did not seek further treatment for her back and leg symptoms over the next three months; however, she testified that her symptoms did not go away and that she simply “toughed it out.” By some time in July 2005, the employee was having trouble walking in the afternoons and began borrowing a wheelchair at hospitals and nursing homes to use while going to patient’s rooms.
The employee telephoned Dr. Holte’s office on July 29, 2005. She spoke to a nurse and stated she had been doing well after physical therapy but about a week ago had a return of left leg symptoms. She had already called Dr. Vorlicky who referred her for a lumbar MRI and suggested she follow up with Dr. Holte.
Some time before mid-August the employee wrote a letter to the employer giving 30 days notice and stating that she needed to resign her position “due to continuing pain and complications from my workers’ comp injury of March 30th.” After receiving the letter, the employer waived the notice and the employee’s employment ended effective August 15, 2005. The employee was then 71 years of age, but testified that it was not her intention to retire.
Dr. Holte noted his review of the MRI scan on August 9, 2005. He concluded that the L5-S1 and L2-3 levels, above and below the employee’s fusion, showed no obvious herniations. Because the MRI was somewhat unclear, he suggested that the employee undergo a CT myelogram. The CT showed severe spinal stenosis at L2-3 thought to be secondary to hypertrophic facet joints. The employee was seen by Dr. Holte on September 19, 2005, for evaluation and discussion of possible surgery. X-rays on that date indicated advanced degeneration of the L-2 disc, the level just above the employee’s fusion, with lateral tipping of L2 on L3 and scoliosis at that level associated with loss of disc height. Dr. Holte recommended that the employee have a decompression and extension of her fusion at the L2-3 level.
Dr. Holte performed the employee’s surgery on September 19, 2005. His operative description indicates that he found large hypertrophic facet capsules and associated synovial cysts on the left side of the L2-3 level, with very severe stenosis. He did not see any disc herniations on moving the dura. Four weeks after the surgery, on October 18, Dr. Holte examined the employee. X-rays showed the new hardware in her back in good position. The employee reported that she still had some intermittent left lateral leg pain, but that it seemed to be improving. Dr. Holte wrote that she was doing well with good early improvement.
The employee was seen by Dr. Daniel Randa on December 21, 2005, for a medical examination on behalf of the self-insured employer. Dr. Randa took a history from the employee essentially consistent with that recited herein. He also reviewed the employee’s rather voluminous medical records. Dr. Randa noted that the records revealed longstanding degenerative spondylosis, chronic lumbar pain, and radiculopathy. Based upon the examination and the employee’s records and history, Dr. Randa opined that the employee’s October 17, 2002, work injury had resulted in a thoracolumbar musculoligamentous strain from which maximum medical improvement was reached by December 31, 2002, and which resolved without any permanent residual effects. He was of the opinion that the March 30, 2005, work incident had caused a temporary aggravation of the employee’s preexisting lumbar degenerative spondylosis with low back pain extending to the left leg, but that this resolved with a brief course of physical therapy treatment by April 11, 2005, when the employee was noted to be able to walk briskly without discomfort and was discharged from physical therapy. Dr. Randa noted particularly that neither the radiological studies and scans, nor any findings at the time of the 2005 surgery, suggested that an acute injury to the L2-3 interspace had occurred as a consequence of the March 30, 2005, work incident. He considered the employee’s later symptoms and need for surgery to be entirely caused by the preexisting degenerative processes aggravated by her prior L3-L5 fusion.
In early January 2006, the employee fell while at her bank when her walker got caught on a rubber floor mat. She was seen at the emergency room at Fairview Southdale Hospital on January 3 complaining of pain in the low back, right elbow, and knee after the fall. X-rays verified that her fusion had not been affected. The employee still had bruises from this fall on January 10, 2006, when she was seen by Dr. Holte in follow up for her fusion. The employee told him that her leg symptoms had diminished after the surgery but had now worsened since she fell. An MRI scan was recommended. The scan, performed on January 27, 2006, showed an apparently solid fusion. There was no herniation at L5-S1, though there was degenerative foraminal stenosis on the right without ganglionic compression. The employee was reporting right leg pain from her hip to her knee, but Dr. Holte could see nothing on the MRI to account for that.
In April 2006, it was discovered that the employee’s left hip replacement was loosening, with obvious osteolysis of the left femoral component. On May 8, 2006, the employee underwent a revision femoral arthroplasty to revise her left hip prosthesis. She developed a hip infection following the surgery, and required prolonged hospitalizations and procedures due to the infection and to recurrent hip dislocations.
As of February 20, 2007, the employee continued to have ongoing low back pain which had worsened following her hip surgeries, but her fusion was still solid. In a chart note dated March 20, 2008, Dr. Holte noted that he had reviewed a typewritten sheet the employee had prepared and agreed with her description of her limitations. He also offered the opinion that the employee’s work injury in 2005 “herniated her disc at the L2/3 level [and] caused severe stenosis and required extension of her fusion . . . in September of 2005.”
On February 7, 2008, the employee was seen by Dr. Robert Wengler for a medical examination at the request of her attorney. Dr. Wengler opined that the employee’s 2002 work injury resulted in destabilization of the employee’s L2-3 disc level and precipitated symptoms sufficient to lead to a recommendation, which the employee resisted, for the extension of her prior fusion to that level. He considered the March 30, 2005, work incident to have caused a significant aggravation which was followed by the development of intractable left lower extremity sciatica necessitating the L2-3 surgery. In deposition testimony, Dr. Wengler further opined that if the employee’s use of a walker was due to the recovery process from the 2005 back surgery, he would deem any injuries sustained as a result of her fall at her bank in January 2006, including her hip loosening and the subsequent hip revision surgery and her hip infections, to be consequential to her back injury.
The employee’s claims were heard before a compensation judge of the Office of Administrative Hearings on October 14, 2008. Following the hearing, the judge found that the 2002 and 2005 work injuries were temporary in nature, and did not contribute to the employee’s need for the 2005 L2-3 fusion or to a consequential hip injury. The employee appeals.
The primary issue in this case, and the central issue in this appeal, is whether the employee’s 2002 and 2005 work injuries were temporary aggravations to her pre-existing low back problems, as determined by the compensation judge, or whether they had permanent, ongoing effects which contributed to the employee’s need for an extension of her fusion to the L2-3 level in 2005 or which led to an alleged consequential hip injury, following a fall in 2006.
This court has identified a number of factors which a compensation judge may consider in determining whether an aggravation of a pre-existing condition is permanent or temporary. Those factors are: (1) the nature and severity of the pre-existing condition and the extent of restrictions and disability resulting therefrom; (2) the nature of the symptoms and extent of medical treatment prior to the aggravating incident; (3) the nature and severity of the aggravating incident and the extent of restrictions and disability resulting therefrom; (4) the nature of the symptoms and extent of medical treatment following the aggravating incident; (5) the nature and extent of the employee’s work duties and non-work activities during the relevant period; and (6) medical opinions on the issue. McClellan v. Up North Plastics, slip op. (W.C.C.A. Oct. 18, 1994). “Which of these factors are significant in a particular case and the weight to be given to any factor is generally a question of fact for the compensation judge.” Wold v. Olinger Trucking, Inc., slip op. (W.C.C.A. Aug. 29, 1994).
Questions of medical causation fall within the province of the compensation judge. Felton v. Anton Chevrolet, 513 N.W.2d 457, 50 W.C.D. 181 (Minn. 1994). In determining such questions, it is the compensation judge's responsibility, as trier of fact, to resolve conflicts in expert testimony, and this court generally must affirm findings that are based upon the judge’s choice between the divergent opinions of medical experts, unless the opinion chosen lacks adequate foundation. Nord v. City of Cook, 360 N.W.2d 337, 342, 37 W.C.D. 364, 372 (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, 734, 40 W.C.D. 948, 957 (Minn. 1988).
In the present case, the employee had a history of low back problems going back to 1966. She had been diagnosed with degenerative disc disease and had sciatica involving the left leg by 1978. MRI studies in 1998 showed stenosis at multiple levels of the employee’s low back, severe at L3-4 and L4-5, but also present at the L2-3 level. The progression of this condition led to worsening left leg pain and was treated in 2000 with a fusion from L3 to L5. The employee continued, however, to have some left leg sciatica, even following the fusion at the most severely stenotic levels.
Thus the compensation judge was confronted with the difficult task of determining whether the employee’s subsequent low back symptoms and treatment were due solely to the effects of her longstanding degenerative low back condition, or whether they were due to aggravation from the two work injuries in 2002 and 2005. The medical opinions in evidence reached opposing conclusions on the duration and effect of these two work injuries. Dr. Wengler opined that the employee’s 2002 work injury resulted in destabilization of the employee’s L2-3 disc level and that the March 30, 2005, work incident was followed by the development of intractable left lower extremity sciatica, both of which aggravated the natural degenerative processes in the employee’s low back sufficiently to necessitate the L2-3 surgery. Dr. Randa, on the other hand, offered the opinion that the 2002 and 2005 injuries each resulted only in relatively brief aggravations of the employee’s longstanding degenerative lumbar disease, both of which resolved fairly promptly without lasting effects, and that the subsequent extension of the prior fusion to the next adjacent level at L2-3 was the result solely of the continuing progression of the pre-existing non-work condition coupled with the effects of the employee’s prior fusion.
The compensation judge expressly found the opinion of Dr. Randa more persuasive and more consistent with the history of the employee’s symptoms as indicated from her review of the employee’s medical records. In her memorandum, the judge mentions several factors she found significant. Among these, she noted that the medical records made during the initial months immediately following both work incidents failed to show examination findings suggestive of an acute injury sufficient to result in permanent destabilization or damage to the employee’s lumbar spine. This was also consistent with the surgeon’s notes from the 2005 fusion, which indicated that he observed severe stenosis, but no visible disk injury or herniation. In addition, neither injury resulted in time off work for the employee or in new work restrictions.
Further, as the compensation judge notes in her memorandum, the employee’s medical records do not completely support her position that her low back condition was changed by the injuries in 2002 and 2005. After her 2002 injury, she received no medical care until October 24 when she saw Dr. Vorlicky for a knee injection which had been scheduled earlier. With regard to her back, Dr. Vorlicky noted, “She denies any trauma.” The employee missed no work after the 2002 injury and there was no change in her work restrictions. After the 2005 work incident, the employee saw Dr. Moser on March 31. The employee advised him about the incident in the hospital but, on examination, Dr. Moser noted active and equal reflexes, adequate motor strength, no sensory deficit, and no pain with internal/external rotation. Dr. Moser concluded the employee was not having any disc pathology. The employee was prescribed 10 sessions of physical therapy, but her improvement was deemed sufficient and she was discharged after only three sessions. Following this discharge from physical therapy, the employee did not seek further medical treatment for her back for about three months, and when she next sought treatment told the doctor that she had been doing well after the physical therapy and that she had started to experience left leg pain again only about a week earlier.
In her brief, the employee points to her testimony that her back pain changed permanently after the 2002 work injury pushing the cart, and that after the 2005 work injury there was a permanent aggravation to her leg pain, which did not resolve after physical therapy in April, and which gradually worsened by July 2005 causing her to resign her employment. The principal argument raised by the employee on appeal, although stated variously in different forms under several headings in her brief, involves the contention that Dr. Randa and the compensation judge both gave insufficient weight to her testimony as to the nature and duration of her symptoms.
First, she contends that her testimony constituted sufficient proof of a permanent injury, citing cases holding that the existence of a personal injury may be established on an employee’s subjective complaints coupled with the opinion of a medical expert. She argues that the compensation judge erred in failing to discuss her testimony in her findings or memorandum; that the failure to do so shows that the judge failed to consider that part of the evidence, denying her due process; and that the judge applied an erroneous standard of proof by focusing principally on the objective medical findings and the medical records.
We disagree. Although we agree that the compensation judge could have relied on the employee’s testimony to find one or both of the injuries here to have been permanent in nature, she was not required to accept that testimony where inconsistent with her reasonable interpretation of the other evidence in the case. The question on appeal is not whether there was evidence by which the judge might have reached a different conclusion, but whether the conclusion she did reach has sufficient support in the record. Nor was she required to discuss the testimony or make explicit finding about its credibility. See Regan v. VOA Nat’l Housing, 61 W.C.D. 142 (W.C.C.A. 2000) (a compensation judge is not required to refer to or discuss every piece of evidence introduced at the hearing). The judge’s memorandum specifically states that she did consider the employee’s testimony in reaching her determinations in the case. Although that testimony is not discussed in detail in the memorandum, she apparently considered it to be less reliable than the evidence of the medical records. A finding inconsistent with a party’s testimony on a matter will usually be viewed on appeal as an implicit finding as to that testimony’s credibility. Cf., e.g., Brennan v. Joseph D. Brennan, M.D., 425 N.W.2d 837, 41 W.C.D. 79 (Minn. 1988).
The employee contends that the compensation judge should have adopted the opinion of Dr. Wengler over that of Dr. Randa because Dr. Wengler was a surgeon and Dr. Randa was not; because Dr. Wengler pointed to a scientific study consistent with his opinions about destabilization of discs; because Dr. Wengler specifically discussed a radiological finding of retrolisthesis at L2-3; and because Dr. Randa failed to explain how he arrived at the date of December 31, 2002, as that by which the effects of the 2002 work injury would have ended. These are arguments which go to the weight to be afforded to Dr. Randa’s opinion, rather than its foundation. We do not find them to be of a sufficient weight to require us to overrule the judge’s adoption of Dr. Randa’s expert opinion.
The employee also argues that the compensation judge was led to adopt Dr. Randa’s opinion in part by her view, expressed in her memorandum, that the employee had “essentially” the same kinds of low back and lower extremity findings before and after the 2002 cart incident that she had before and after the May 31, 2000, fusion surgery. The employee contends this is not only contrary to her own testimony, but unsupported by the medical records. We note, however, that the medical records for at least a year following the employee’s surgery are replete with her complaints of low back and left leg pain which she indicated was “as bad” or sometimes “worse” than it had been prior to the surgery. We note also that the employee’s own testimony about that the effects of the 2002 injury was not of a new kind of pain, but that she “would have that pressure pain maybe more often than what I did before.” Subsequently, the employee’s renewed symptoms in July 2005, after which she went on to have an extension of her fusion, were low back pain with intractable sciatica in the left leg. We conclude that the compensation judge’s characterization of the employee’s symptoms, as “essentially” of the same kind both before and after the 2002 work injury, does not constitute a basis for us to reverse.
The judge’s decision and memorandum demonstrate that she fully considered the evidence relevant to whether the 2002 or 2005 work injuries were permanent or temporary in nature, and we find her rationale to be amply supported by the record. We therefore affirm.
 The employee’s testimony was somewhat less compelling on this issue than the employee’s summary suggests:
Q. Okay. Did the back revert to the way it was before this cart or not in your opinion or was there a permanent change?
A. I permanently have the walker by the side of my bed and always use it to get up to stand in the morning.
Q. Was there more pain?
A. Not because of the knee.
Q. I know, but I’m talking about your back after October of 2002?
A. I would have that pressure pain maybe more often than what I did before. I never really, you know, kept track of it, but I always had the pressure pain where I’d have to lean forward and lean on something all the time.
Q. So in your judgment did you go back after some time to the way you felt before the cart incident in October of ’02, did you ever get back to the way it was?
A. No, never.
 See, e.g., Brown v. State, Dep’t of Transp. 54 W.C.D. 60 (W.C.C.A. 1996).