The employee appeals from the compensation judge’s finding that the employee’s April 17, 2002, work injury resolved by November 6, 2002, and his corresponding denial of temporary total disability benefits after that date.  The employer and insurer cross-appeal from the compensation judge’s determination that the employee was entitled to benefits through November 6, 2002, arguing that the effects of the employee’s work injury resolved earlier than November 6, 2002.  We affirm.

In July 2001, Gerald Booth, the employee, began working as an over-the-road truck driver for DFW Enterprises, the employer.  On April 17, 2002, the employee sustained an admitted personal injury to his low back when he slipped and fell while at a truck stop.  The employer and insurer admitted primary liability for the employee’s injury, paid the employee 3.2 weeks of temporary total disability benefits, through May 27, 2002, and paid for two months of medical treatment.  The employer and insurer denied all claimed benefits after May 27, 2002.

Before he began working for DFW, the employee, who is a resident of Ohio, had held other truck driving positions with employers based in Ohio, and had sustained various work-related injuries to his low back, both shoulders, left ankle and left knee.^[1]  On September 19, 1978, while unloading a trailer for Great Plains Bag Corporation, the employee slipped on some paper on the floor and twisted his back.  He noted low back, right buttock, thigh and leg pain, and obtained medical treatment from his family physician.  He was diagnosed as having sustained a sprain of his low back and received conservative treatment for his low back over the following years.  In 1979, the employee underwent a U.S. Department of Transportation (DOT) physical examination, a type of examination required of drivers in the trucking industry, was re-certified for employment as a truck driver, and returned to work.

In December 1980, while driving truck for Great Plains Bag Corporation, the employee injured his left shoulder after slipping on ice as he climbed down from his truck.  He remained off work due to restrictions related to his left shoulder, and later was diagnosed with degenerative joint disease along with anterior shoulder impingement syndrome of the left shoulder.  In March 1982, he underwent left shoulder surgery in the nature of a resection of the distal left clavicle and resection of the coracoacromial ligament.

The employee continued to undergo treatments and consultations for his low back condition, including physical therapy.  In addition, the employee developed depression which was admitted to be a result of his September 1978 and December 1980 work injuries.  He received medical treatment for depression for many years, commencing in April 1983, and periodically has taken anti-depressant medication since then.  The employee has been assigned disability ratings for his depression, including a 25% assessment in January 1989 and a 50% disability rating in April.  Due to his work restrictions and inability to return to the same type of truck driving position that he earlier held, and also due to his treatment for depression and other medical conditions, the employee did not work for income between 1981 and March 1990, and received workers’ compensation benefits and/or social security disability income between 1981 and March 1990.  During that period, he worked as a paralegal for a law firm on a volunteer basis and also performed other volunteer work.
On December 19, 1986, the employee consulted his physician, complaining of stiffness in his low back and right leg.  Medical records reflect that he sought treatment again in 1987 for his low back symptoms and pain radiating into his right leg.  By August 1987, the employee’s treating physician referred him to Dr. Glenn Blakenhorn III, D.O., Massillon, Ohio, a specialist in physical medicine and rehabilitation.  Dr. Blakenhorn noted chronic low back and leg symptoms and suggested vocational rehabilitation due to the nature of the employee’s low back condition and difficulties he was experiencing with his attempts to return to work as a truck driver.

In May 1989, the employee fell, injuring his right arm and shoulder.  Even with conservative treatment and a strengthening program, the employee’s symptoms persisted.  By January 1990, he was diagnosed as having post-traumatic arthritis and synovitis of the right acromioclavicular joint, and later underwent surgical excision of his distal right clavicle.

In March 1990, after having been off work since 1981, the employee returned to work as an over-the-road truck driver, again for an Ohio-based employer, and worked for approximately 13 months.  On April 29, 1991, the employee injured his low back when he fell off a truck while unloading lumber, and also reported that he injured his left knee and ribs as a result of his fall.  He sought emergency medical treatment, complaining of low back and left flank pain, and was diagnosed with a back contusion and strain.  Although the employee underwent conservative treatment, including physical therapy, his symptoms persisted.  He was disabled from work following his 1991 injury, and remained off work until March 2000, again receiving workers’ compensation benefits or social security disability income for at least a portion of that time period.  He underwent extensive conservative medical care which, according to the employee, did not provide significant relief of his low back symptoms.

In 1994, while attending a work hardening program intended to rehabilitate his low back condition, the employee developed an acute worsening of his low back pain and bilateral radicular pain into his legs.  In addition, shortly after that aggravation of his low back symptoms, the employee noted symptoms in his cervical and thoracic spine areas, and later developed headaches.  Due to his ongoing low back symptoms, the employee was referred for evaluation to Dr. T. R. Detamore, a neurosurgeon in Canton, Ohio, who ultimately recommended and performed surgery on December 19, 1994.  That surgery was in the nature of bilateral laminectomy, facetectomy, foraminotomies with nerve root exploration and decompression at the L3, L4 and L5 levels.  By at least October 1995, the employee was diagnosed as having cervical degenerative osteoarthritis, and received treatment for his neck and upper back symptoms on 1995 and 1996.  The employee’s low back symptoms persisted, and by October 1996, he reported persistent and disabling low back, right buttock and lower extremity pain, and was referred to Dr. Jeffrey Cochran, D.O., of TriCounty Orthopedic Surgeons in Massillon, Ohio, for a second opinion and surgical evaluation.  Based on MRI findings and the employee’s reported symptoms, Dr. Cochran determined that the employee’s ongoing low back pain resulted from instability at the L5-S1 disc space, and recommended fusion surgery.  On December 3, 1996, the employee underwent surgery to his low back, performed by Dr. Cochran, in the nature of a revision decompression of the L3, L4 and L5 levels and fusion of the L3-4, L4-5 and L5-S1 vertebral levels.
The employee admittedly had a slow recovery from his 1996 surgery, and remained off work until March 2000, when he returned to work in the trucking industry.  On March 15, 2000, the employee underwent a DOT physical examination and was re-certified to return to work as a truck driver.  Between March 2000 and June 2001, the employee worked as an over-the-road truck driver for Webster Express.  He sustained a left knee injury in December 2000 but evidently was able to continue working following that injury.  In June 2001, the employee resigned from Webster Express and began working for the employer, DFW Enterprises, in mid-July 2001.

On April 17, 2002, while on a trucking run between Cleveland, Ohio, and Georgia, the employee lost his balance and slipped on fuel and water in a parking lot near his truck.  After returning to Ohio, the employee consulted Dr. Brad McKenney at an urgent care center, reporting difficulty walking, pain in his buttocks, and some pain with rotation of legs or hips.  Dr. McKenney initially diagnosed a right hip and buttock contusion, prescribed medication and rest, and released the employee to return to work with limitations related to walking, climbing stairs and climbing ladders.  The employee later followed up with Dr. Cochran, his treating surgeon from 1996.  Lumbar x-rays showed that the fusion from L3 to S1 was solid, and that his surgical hardware was intact.  Although Dr. McKenney originally had released the employee to return to work, Dr. Cochran later restricted him from working until May 28, 2002.  On that date, the employee returned to work at his usual position as an over-the-road trucker and worked until June 8, 2002.

On June 8, 2002, the employee resigned from his position with the employer.  The record contains conflicting evidence regarding the basis for the employee’s resignation.  He left a note for the employer advising that he no longer wished to work for the employer due to conflicts with his driving partner;^[2] the employee, however, testified that his resignation was also based on his ongoing low back symptoms and the physical difficulties he experienced while driving.

At Dr. Cochran’s referral, due to a flare-up of his symptoms, the employee was examined by Dr. Vladmir Djuric, Ohio Rehab Center, on July 15, 2002.  Dr. Djuric found the employee’s condition to be suggestive of sacroiliac joint-mediated pain, and he related that pain to the employee’s April 2002 injury.  Dr. Djuric provided trigger point injections and referred the employee for physical therapy.  Dr. Djuric performed additional injections on September 23 and October 21, 2002.  At his October 21, 2002, appointment, the employee reported that he felt that, overall, he had improved, and that he felt only occasional mild lateral calf discomfort and that his groin pain had decreased.  However, he also reported that his back and hip pain remained unchanged and that his lifting activities aggravated his back, hip and groin pain.

The employee initially attended physical therapy sessions at Tuscarawas Valley Physical Therapy, in Dover, Ohio, between August 30 and October 29, 2002.  According to a chart note written by his physical therapist on November 6, 2002, the employee had undergone 16 out of 24 recommended treatments, and, in spite of multiple contacts made by the physical therapist since October 29, he had not attended additional scheduled appointments. 

On November 14, 2002, the employee again consulted Dr. Djuric, reporting that although his hip and groin pain had improved, he still noted pain on the right side of his low back, along with intermittent bilateral leg pain.  By November 25, the employee reported that his lower extremity symptoms and groin pain had resolved, but that he still noted low back pain.  Dr. Djuric renewed his prescription for physical therapy, and the employee again attended physical therapy on December 6, 2002, but on December 30 was discharged from additional therapy for failure to attend his appointments.  However, Dr. Djuric renewed his prescription for physical therapy, and in January 2003 the employee resumed therapy treatment at Dr. Djuric’s clinic.  He received ongoing treatment in 2003, including physical therapy, trigger point injections, and pain management consultations, but his low back pain persisted.

In 2003, the employee filed a claim petition in Minnesota, seeking payment for temporary total disability benefits for the statutory maximum of 104 weeks, between June 9, 2002, and June 5, 2004.  He also sought benefits based on a rating of 13% permanent partial disability of the body as a whole.  In conjunction with litigation on that claim, Dr. Mark Friedland examined the employee on September 10, 2003, at the request of the employer and insurer.  He concluded that the employee sustained a right hip and/or gluteal contusion with lumbosacral and right SI joint strain/sprain injuries on April 17, 2002.  Based on his review of medical records and radiographic studies, Dr. Friedland concluded that the employee’s fusion was intact, and that there was no evidence of significant degeneration of the vertebral discs above the fusion site.  Dr. Friedland found that the employee’s subjective symptoms exceeded his objective findings on exam and on radiographic studies, and that the employee had reached maximum medical improvement from his April 2002, injury by June 17, 2002, which was a date when Dr. Cochran had again released the employee to return to work without restrictions.  Dr. Friedland assigned a rating of 28% permanent partial disability of the whole body, a rating that he believed would have been present long before the April 2002 injury.  The doctor also found that the employee had not required any further care or treatment for his low back condition since having reached MMI on June 17, 2002.

Dr. Robert Wengler also examined the employee on September 10, 2003, at the request of the employee’s attorney.  He concluded that the employee’s injury on April 17, 2002, resulted in a substantial aggravation of his pre-existing condition and led to his need for further medical treatment, restrictions, and an increase in his ratable impairment.  Dr. Wengler also concluded that the employee was totally disabled from gainful employment, and had been since June 2002.  Dr. Wengler assigned a Weber^[3] rating of 13% permanent partial disability to the body as a whole, explaining that the employee’s “functional impairment attributable to the April 17, 2002 injury is not defined in the Workers’ Compensation Schedule” and that the most plausible explanation for his present difficulties is that he has recurrent nerve root irritation and sciatica secondary to disruption of a fusion segment.  Dr. Wengler reexamined the employee on January 3, 2005, and outlined his findings from that examination in his deposition testimony taken in conjunction with the later hearing.

By December 2003, Dr. R. Douglas Orr, at the Cleveland Clinic, concluded that the employee’s fusion was solid from the L3 level to at least the L5 level, but noted that it was difficult to discern the condition at L5-S1.  In an attempt to alleviate the employee’s symptoms, Dr. Orr later recommended surgery for removal of the hardware inserted earlier; that procedure was accomplished on January 29, 2004.  The employee reported significant pain relief post-surgery, and he participated in a post-surgery exercise program, but by April 2004 the employee reported that his pain had worsened and that he felt periodic severe pain and numbness in both legs.  The employee was evaluated at the VA Hospital in Cleveland; diagnostic testing showed no abnormalities, including none in the areas treated by surgery.  The employee received lumbar facet blocks between May and July 2004.

An evidentiary hearing was held on January 7, 2005, to address the employee’s claim petition.  The hearing record closed on January 31, 2005.  In his findings and order served and filed March 31, 2005, the compensation judge found that the employee had sustained a temporary injury on April 17, 2002, which resolved by November 6, 2002, and that the injury did not represent a substantial contributing factor to any wage loss or medical expenses incurred after November 6, 2002.  The compensation judge also found that the employee’s injury of April 17, 2002, did not result in any permanent partial disability.  The compensation judge awarded payment of temporary total disability benefits and medical expenses from June 12, 2002, through November 6, 2002, and denied the claim for benefits thereafter.^[4]

The employee appeals from the finding that the injury was temporary in nature and from the corresponding denial of benefits after November 6, 2002.  The employer and insurer cross-appeal from the finding that the period of the temporary aggravation extended until November 6, 2002, arguing that it lasted no longer than June 17, 2002.

The compensation judge found that the employee’s work injury of April 17, 2002, was temporary in nature and that it fully resolved by November 6, 2002.  The employee appeals from that finding and from the denial of benefits after November 6, 2002.  He argues that in spite of his medical history, including his history of low back injuries and related medical treatment, he had made a nearly full recovery from his 1996 fusion surgery, as verified by two DOT examiners, and would have been able to continue working full-time as a truck driver, with minimal low back symptoms, if he had not slipped and fallen while at work on April 17, 2002.  The employee also argues that the evidence supports a finding that the employee’s 2002 injury was permanent, as the record contains no medical opinion, nor contemporaneous records,  that he had recovered from the effects of his April 17, 2002, injury by November 6, 2002.

The employer and insurer cross-appeal from the findings and order, arguing that although the employee’s injury resulted in a temporary aggravation of his pre-existing condition, that aggravation resolved by at least June 17, 2002.  They rely upon Dr. Friedland’s opinion and testimony in support of their cross-appeal.

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).  After his review of the extensive records in evidence, as well as testimony presented by the employee and one of the employer’s owners, the compensation judge found that the evidence in this case failed to show that the employee’s current low back complaints were causally related to his April 17, 2002, work injury.  Although the judge acknowledged the employee’s traumatic injury in April 2002 and the employee’s testimony about his ongoing low back complaints since 2002, the judge also noted the employee’s extensive pre-existing condition prior to 2001 when he began working for the employer.  In his findings, the compensation judge thoroughly outlined the employee’s medical and employment history, and it is obvious from the findings that the compensation judge carefully reviewed the record when evaluating the employee’s claims and when determining whether the employee’s aggravating injury in 2002 was temporary or permanent.

The record contained medical opinions from various treating physicians, and also from Drs. Robert Wengler and Mark Friedland, both of whom conducted independent medical examinations and presented deposition testimony.  When concluding that the employee sustained a temporary aggravation on April 17, 2002, the compensation judge relied in part, but not solely, on Dr. Friedland’s opinion.  The judge adopted Dr. Friedland’s opinion that the employee’s 2002 work injury no longer represents a substantial contributing cause of his low back condition or symptoms.  But he determined that the duration of the temporary aggravation was longer than was assessed by Dr. Friedland.  Whereas Dr. Friedland concluded that the temporary aggravation caused by the employee’s April 2002 injury resolved within two months, by June 17, 2002, the compensation judge concluded that the injury did not resolve until November 6, 2002.  A compensation judge generally may accept all or only part of any witness’s testimony, City of Minnetonka v. Carlson, 298 N.W. 2d 763, 767 (Minn. 1980), and the judge did not err by relying on a portion of Dr. Friedland’s opinion.  In addition, medical opinions are only one factor which the compensation judge may consider to determine whether an injury is a temporary or permanent aggravation.  See Burth v. St. Paul Collision Ctr., slip op. (W.C.C.A. Nov. 23, 1994).

Whether the employee’s injury of April 2002 aggravated his pre-existing condition is a question of fact.  Bender v. Dongo Tool Co., 509 N.W.2d 366, 367, 49 W.C.D. 511, 513 (Minn. 1993).  In addition to medical opinions, a judge may base his conclusions on other reliable evidence in the record.  See Reimer v. Minnit Tool/M.I.T. Tool Corp., 520 N.W.2d 397, 51 W.C.D. 153 (Minn. 1994).  The employee argues that the compensation judge misinterpreted the medical evidence and that the compensation judge’s findings are not consistent with the analysis presented in Wold v. Olinger, slip op. (W.C.C.A. Aug. 29, 1994).  In Wold, this court stated that:

Although there is evidence in this case that the employee’s low back condition did not return to his pre-injury condition, including evidence presented by the employee’s testimony, the issue on appeal is not whether substantial evidence would support an alternative finding, but whether substantial evidence supports the judge’s findings.  See Land v. Washington County Sheriff’s Dep’t, slip op. (W.C.C.A. Dec. 23, 2003); see also Ludford v. Honeywell, Inc., slip op. (W.C.C.A. Mar. 17, 2004); Moe v. Dr. Matthew A. Gahn, slip op. (W.C.C.A. Dec. 31, 2003).  In addition, “[w]here more than one inference may reasonably be drawn from the evidence, the compensation judge's findings shall be upheld."  Nord v. City of Cook, 360 N.W.2d 337, 342, 37 W.C.D. 364, 372 (Minn. 1985).  We conclude that there is substantial evidence in the record, including medical opinion and extensive medical records, supporting the compensation judge’s findings that the employee’s work injury caused a temporary aggravation of his pre-existing low back condition.  As the compensation judge’s determination is supported by substantial evidence and is not clearly erroneous, we must, under this court’s standard of review, affirm that decision.  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 37 W.C.D. 235 (Minn. 1984).  We accordingly affirm the findings and order and the denial of the employee’s claims for any disability benefits beyond November 6, 2002.

In their cross-appeal, the employer and insurer concur with the compensation judge’s conclusion that the employee’s 2002 low back injury no longer substantially contributes to his current condition and low back symptoms, but they also argue that the employee’s temporary aggravation had resolved at least by June 17, 2002, as determined by Dr. Friedland, or even by late May 2002, when the employee returned to work after being released to work by Dr. Cochran.  They assert that the employee was able to continue working until June 8, 2002, and that he resigned for reasons unrelated to his low back injury.  They further argue that there is no medical opinion in the record stating that the employee’s aggravation had resolved by November 6, 2002.

While it is true that the record does not contain a medical opinion specifying the date of November 6, 2002, as the date by which the employee’s aggravation had resolved, the record contains other evidence to support that conclusion.  The compensation judge noted that the employee stopped attending therapy at Tuscarawas Valley Physical Therapy in late October 2002, and the records from that provider showed a progression in his care during the early fall of 2002.  According to the physical therapist’s chart note of November 6, 2002, the employee had attended 16 out of 24 sessions but had not attended scheduled visits since October 29 despite attempted contacts with the employee.   The judge also noted that by November 25, 2002, the employee reported a resolution of his groin and lower extremity symptoms.  Based on this information and based on the entire evidence of record, the compensation judge could reasonably conclude that the employee’s temporary aggravation of his pre-existing condition had resolved by November 6, 2002.  We affirm the compensation judge’s finding that the employee’s temporary aggravation did not resolve until November 6, 2002.