THOMAS J. TROSSEN, Employee, v. CENTRAIRE, INC., and FEDERATED MUT. INS. CO., Employer-Insurer/Appellants, and CENTRAIRE, INC., and EVEREST NAT'L INS., adm'd by BERKLEY RISK SERVS., Employer-Insurer/Cross-appellants, and SHEET METAL #10 BENEFIT FUND, NORTH MEMORIAL HEALTH CARE, and INSTITUTE FOR ATHLETIC MEDICINE, Intervenors.

 

WORKERS= COMPENSATION COURT OF APPEALS

FEBRUARY 7, 2000

                                                                             

HEADNOTES

 

CAUSATION - SUBSTANTIAL EVIDENCE.  Where it was supported by expert medical opinion of proper foundation and by other evidence and testimony of record, the compensation judge=s conclusion that the employee sustained a permanent injury to his right arm, right shoulder and neck partly as a result of his work activities in September 1996, and that that injury substantially contributed to the employee=s need for chronic pain treatment, was not clearly erroneous and unsupported by substantial evidence.

 

APPORTIONMENT - EQUITABLE.  Where it was reasonably supported by occupational therapy records, expert medical opinion, and other evidence of record, the compensation judge=s equitable apportionment of liability for the employee=s temporary disability and need for medical and chronic pain treatment was not clearly erroneous and unsupported by substantial evidence.

 

Affirmed.

 

Determined by Pederson, J., Johnson, J., and Rykken, J.

Compensation Judge:  Catherine A. Dallner

 

 

OPINION

 

WILLIAM R. PEDERSON, Judge

 

The employer and Federated Mutual Insurance Company appeal from the compensation judge=s equitable apportionment of the employee=s disability from and after September 9, 1996.  The employer and Everest National Insurance Company cross-appeal, both from that apportionment and from the judge=s findings that the employee sustained a permanent injury to his right arm, right shoulder, and cervical spine on September 9, 1996, and that that injury is a substantial contributing cause of the employee=s diagnosed chronic pain syndrome and claim for benefits after September 9, 1996.  We affirm.

 

BACKGROUND

 

On June 26, 1996, Thomas J. Trossen sustained a work-related injury to his right hand in the course of his employment as a sheetmetal worker for Centraire, Inc. [the employer], for whom he had worked since about 1988.  On the date of his injury, Mr. Trossen [the employee] was forty-six years old and was earning an average weekly wage of $987.05.  The employer was insured at the time against workers= compensation liability by Federated Mutual Insurance Company [together with the employer, Federated].  Shortly after the injury, the employee underwent surgery performed by orthopedist Dr. Joseph Teynor, who repaired a rupture of the extensor tendon of the ring finger and lacerations on both that and the small finger of the right hand.  Following surgery, the employee was released to return to work on July 3, 1996, with prescriptions for splinting and physical therapy.  His hand was apparently in a splint and his arm in a sling from that time until about early September 1996.

 

From the date of his injury in June until September 9, 1996, the employee=s duties at work were primarily supervisory.  He was assisted by a student from Dunwoody Institute, whose activities he closely directed.  The employee evidently performed occasional manual tasks such as measuring or drawing layouts, but he performed these tasks with his left hand.  As of September 9, 1996, the employee was still in physical therapy for his right hand. 

 

On September 9, 1996, the employee worked alone for the first time since his injury of June 26, 1996.  He evidently felt weakness in his upper shoulder and back that day, due to his arm having been in a sling for the past two months.  On that date, he was working on his knees disassembling light diffusers from ceiling tile, using a battery drill to remove screws from the diffuser boxes.  He evidently noticed that his arm and upper body were getting tired and that he was having difficulty holding the drill steady on the screws.  While holding the drill in his right hand, he experienced a sudden, burning sensation in his right shoulder, and his right arm felt Aparalyzed.@  The pain extended from his neck down to his shoulder blade and into his back, and he could not move his fingers.  The employee notified his employer that he had hurt himself and did not complete his shift.  On the date of the incident, the employee was earning an average weekly wage of $1,016.20, and the employer was insured against workers= compensation liability by Everest National Insurance [together with the employer, Everest].

 

The employee did not seek medical treatment on September 9, 1996, because he already had an appointment scheduled with Dr. Teynor for September 11, 1996.  On the latter date, Dr. Teynor diagnosed mild impingement in the right shoulder and mild lateral epicondylitis of the elbow, reporting Ano evidence of any cervical problem.@  He recommended no repetitive use of the arm, especially above shoulder level, for six weeks.  The employee did not return to see Dr. Teynor after September 11, 1996.

 

During the remainder of September, the employee saw several doctors, including orthopedist Dr. George Osland, all of whom directed their diagnoses to the right shoulder.  On February 17, 1997, Dr. Osland noted that the employee Adoes have some radiation into the vertebral border of the scapula,@ and he ordered x-rays of the cervical spine.  The x-rays were interpreted as normal, and Dr. Osland referred the employee for a right shoulder MRI on March 7, 1997.  The MRI showed some evidence of acromial bursitis but no evidence of a rotator cuff tear.

 

Apparently Dr. Osland retired from practice, and the employee came under the care of Dr. Joseph Bocklage.  On August 7, 1997, Dr. Bocklage concluded that the employee=s complaints were consistent with a cervical radiculopathy, and he recommended an MRI of the cervical spine.  The employee=s MRI, performed on August 22, 1997, was interpreted as showing a right paracentral broad-based C5-6 disc herniation.  Dr. Bocklage referred the employee for a neurosurgical consultation with Dr. Terry Hood on October 15, 1997.  Dr. Hood diagnosed a right C6 radiculopathy secondary to the disc herniation.  When conservative measures did not relieve the employee=s symptoms, Dr. Hood performed a C5-6 anterior cervical diskectomy and fusion and plating on December 1, 1997.  The employee testified that he did not have any pain in the scapula or arm following surgery, and on February 23, 1998, Dr. Hood concluded that the employee was ready for a work hardening program.  The employee commenced his work hardening program on March 31, 1998, but subsequent to beginning his upper extremities reconditioning he developed a significant increase in pain and tingling in his arm and pain over his shoulder blade.  The employee indicated that the symptoms that returned after surgery were worse than the symptoms he had experienced prior to surgery.

 

On May 20, 1998, the employee underwent a cervical myelogram and CT scan of the cervical spine.  The study did not identify any evidence of nerve root compression, and Dr. Hood referred the employee to Dr. Alan Bensman, a specialist in physical medicine and rehabilitation.  On June 2, 1998, Dr. Bensman noted right upper trapezius and scalene myofascial involvement, as well as mild right median nerve conduction delay across the carpal tunnel area.  Dr. Bensman diagnosed deconditioning and referred the employee for physical therapy and a supervised reconditioning exercise program.  In an office note on July 16, 1998, Dr. Bensman noted that the employee=s pain complaints were complicated by a component of sleep alteration and situational depression.

 

On August 11, 1998, the employee saw Dr. Robert Clift, Ph.D., with regard to his psychological state and pain complaints.  After taking a detailed history from the employee and administering a battery of psychological tests, Dr. Clift diagnosed a chronic pain syndrome with depression and recommended a chronic pain rehabilitation program.  Meanwhile, Dr. Bensman continued the employee=s exercise program and referred the employee for biofeedback and relaxation training.

 

Following the incident of September 9, 1996, Federated commenced payment of wage replacement benefits, which it paid through October 21, 1996.  On October 29, 1998, the employee filed a Claim Petition against Federated, alleging entitlement to temporary total disability benefits continuing from December 1, 1997, as a result of injuries to his right hand, right arm, right shoulder, and cervical spine sustained on June 26, 1996, and September 9, 1996.  The employee also claimed entitlement to rehabilitation services and medical benefits, including payment for the cervical discectomy and fusion performed on December 1, 1997.  In an Answer filed February 17, 1998, Federated admitted liability for the employee=s right hand injury but specifically denied liability for the claimed right shoulder, right arm, and cervical spine injuries. 

 

On March 17, 1998, the employee was examined for Federated by Dr. Elmer Salovich.  Dr. Salovich related the lacerations of the right ring and little fingers to the work injury of June 26, 1996.  He concluded that the employee=s shoulder symptoms, which had first appeared on September 9, 1996, were a manifestation of a degenerative cervical disc.  He further opined that, while the employee did sustain a herniated disc at work on September 9, 1996, the herniation was due to the natural progression of degenerative disc disease and not to the employee=s work activities.

 

On July 20, 1998, Federated filed a Petition for Temporary Order, contending that benefits paid by Federated after September 9, 1996, were paid under a mistake of fact and that the employee=s disability since December 1, 1997, was due to the employee=s injury of September 9, 1996, or, in the alternative, to a combination of that and the employee=s June 26, 1996, injury.  Federated also filed a Petition for Joinder of Everest.  On August 20, 1998, Federated=s Petition for Temporary Order was granted, and on September 14, 1998, an Order for Joinder of Everest was issued.

 

On November 4, 1998, the employee was examined for Everest by Dr. Michael Smith.  In a report of that same date, Dr. Smith opined that the employee=s injury of June 26, 1996, was the cause of the employee=s need for tendon laceration repair.  He concluded that the employee had an excellent surgical result and that the hand injury had resolved without permanent disability.  He also found that the employee=s job duties on September 9, 1996, had caused a shoulder sprain/strain syndrome.  He believed that the employee=s posterior scapular pain, anterior and lateral shoulder pain, and arm pain were related to the shoulder complaints.  He related the employee=s cervical disc syndrome and consequential surgery to the employee=s long-standing degenerative disc disease and not to any work events in June or September of 1996.

 

On December 10, 1998, based on the reports of Drs. Salovich and Smith, Federated filed a Petition to Discontinue Workers= Compensation Benefits on the ground that the employee=s cervical spine condition was unrelated to either his June 26, 1996, or his September 9, 1996, injury.

 

The employee=s Claim Petition and Federated=s Petition to Discontinue were consolidated for hearing on April 2, 1999.  Evidence offered at hearing included the deposition testimony of Drs. Smith and Bensman.  Dr. Smith testified that the employee=s work activities on September 9, 1996, did not contribute to the degenerative cervical disc disease that prompted the employee=s need for surgery on December 1, 1997.  Dr. Smith diagnosed the employee=s September 9, 1996, injury as merely a strain/sprain of the right shoulder that should have resolved within six months of the onset of symptoms.  He further attributed the employee=s chronic pain syndrome to deconditioning and depression and not to the employee=s right shoulder injury.  Dr. Bensman, on the other hand, testified that the employee sustained an injury to his cervical spine, right shoulder, and right arm as a substantial result of his work activities on September 9, 1996.  Dr. Bensman opined that the employee sustained a cervical disc herniation on September 9, 1996, and that that injury was a substantial contributing cause of the employee=s need for surgery on December 1, 1997, and for chronic pain treatment.

 

In a Findings and Order dated July 21, 1999, the compensation judge found a specific personal injury to the employee=s right arm, shoulder, and cervical spine on September 9, 1996, that resulted in a permanent injury.  Further, the compensation judge concluded that both the June 26, 1996, and the September 9, 1996, injuries were substantial contributing causes of the employee=s chronic pain syndrome, temporary total disability, temporary partial disability, and need for rehabilitation services after September 9, 1996.  The judge apportioned 50% of the liability to the injury of June 26, 1996, and 50% of the liability to the September 9, 1996, injury and ordered Everest to reimburse Federated for 50% of all amounts it had paid since September 9, 1996.  Both Federated and Everest appealed.

 

STANDARD OF REVIEW

 

In reviewing cases on appeal, the Workers= Compensation Court of Appeals must determine whether Athe findings of fact and order [are] clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.@  Minn. Stat. ' 176.421, subd. 1 (1992).  Substantial evidence supports the findings if, in the context of the entire record, Athey are supported by evidence that a reasonable mind might accept as adequate.@  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 59, 37 W.C.D. 235, 239 (Minn. 1984).  Where evidence conflicts or more than one inference may reasonably be drawn from the evidence, the findings are to be affirmed.  Id. at 60, 37 W.C.D. at 240.  Similarly, A[f]actfindings are clearly erroneous only if the reviewing court on the entire evidence is left with a definite and firm conviction that a mistake has been committed.@  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).  Findings of fact should not be disturbed, even though the reviewing court might disagree with them, Aunless they are clearly erroneous in the sense that they are manifestly contrary to the weight of the evidence or not reasonably supported by the evidence as a whole.@  Id.

 

DECISION

 

Nature and Extent of the September 9, 1996, Injury

 

Everest contends that the compensation judge=s findings relative to the incident of September 9, 1996, are clearly erroneous and unsupported by substantial evidence.  They argue first that it is clear from the employee=s testimony that the symptoms the employee experienced on September 9, 1996, were a direct consequence of the earlier injury.  They argue that the employee=s activities on September 9, 1996, which he characterized as among the lightest of physical activities he had ever performed as a sheetmetal worker, would not have resulted in an onset of symptoms on that date but for the deconditioning and weakness of the right hand, arm, and shoulder area caused by immobilization following the employee=s surgery on June 26, 1996.  They assert that, had the employee been performing the same activities at home and developed the same symptoms, no one would question Federated=s ongoing responsibility for such a consequential injury.  We are not persuaded.

 

The compensation judge rejected Everest=s theory of a consequential injury in reliance on the opinions of Dr. Bensman.  Although he subscribed in part to the consequential injury theory, Dr. Bensman found that the positioning of the employee=s neck, head, and arm, compounded by the altered strength and function in the right hand due to the previous injury and the lack of full reconditioning, substantially contributed to the employee=s injury.^[1]  A trier of fact's choice between experts whose testimony conflicts is usually upheld unless the facts assumed by the expert in rendering his opinion are not supported by the evidence.  Nord v. City of Cook, 360 N.W.2d 337, 342-43, 37 W.C.D. 364, 372-73 (Minn. 1985).  The compensation judge=s determination that the injury of September 9, 1996, was a new and separate injury has more than adequate support in the record.

 

Everest=s second argument is that the employee did not sustain an injury to his neck at all on September 9, 1996, that all treating doctors diagnosed the employee=s condition as shoulder-related for nearly a year after the September incident, without even considering the neck until half way through that period.  They contend that Dr. Bensman=s opinions to the contrary were fluctuating, were contrary to medical reports made contemporaneous with the injury, and, because not based on direct observation, were without proper foundation.  We are not persuaded.

 

The employee testified to a traumatic onset of symptoms on September 9, 1996, that involved his right trapezius, right scapular area, right shoulder, and right arm.  Those symptoms persisted from the date of injury until the employee was seen by orthopedist Dr. Joseph Bocklage.  Dr. Bocklage felt that the employee=s symptoms were consistent with a pattern of cervical radiculopathy, and he arranged for an MRI scan.  The MRI documented a C5-6 lesion, and Dr. Bocklage sought the input of neurosurgeon Dr. Terry Hood, who performed a C5-6 anterior cervical diskectomy and fusion at that level of the employee=s cervical spine.  Drs. Bocklage, Hood, Salovich, and Bensman all agreed that the employee=s persistent shoulder and arm complaints following September 9, 1996, were consistent with radicular-type symptoms which would have resulted from a herniated disc.  In accepting Dr. Bensman=s opinion, the judge noted that Dr. Bensman had been the employee=s primary treating physician since June 2, 1998, and had examined and evaluated the employee on numerous occasions.  The doctor was clearly aware of the employee=s medical treatment subsequent to September 9, 1996, including the x-rays of his cervical spine on February 17, 1997, and the subsequent MRI scan.  He was familiar with the employee=s actual work activities performed on September 9, 1996, both from discussions with the employee and from hypotheticals posed by the employee=s attorney.  It was reasonable and within the compensation judge=s discretion to rely on the opinion of Dr. Bensman.  See Nord, 360 N.W.2d at 342-43, 37 W.C.D. at 372-73.

 

Everest also contends that the overwhelming evidence supports a finding that the injury of September 9, 1996, was, at most, a temporary right shoulder sprain/strain.  They again contend that all of the doctors who treated the employee prior to Dr. Bocklage=s examination diagnosed only a soft tissue injury to the right shoulder.  They contend that such an injury would be one that would resolve relatively quickly.  In addition to the opinions of the treating physicians, they rely upon Dr. Smith=s opinion that the events of September 9, 1996, involved such limited physical activity that they could account for no more than a sprain/strain of the shoulder.  Here, too, we are not persuaded.

 

The employee testified that except for a brief period of relief following his surgery on December 1, 1997, he experienced pain in his right arm and shoulder from the date of injury until the date of hearing.  The compensation judge did not accept Dr. Smith=s opinion that the employee=s injury of September 9, 1996, related only to the shoulder and should have resolved within a relatively short time.  The compensation judge=s conclusion that the employee=s injury of September 9, 1996, was permanent was supported by medical records and by the employee=s testimony.  Therefore the  compensation judge=s conclusion is affirmed.  See Hengemuhle, 358 N.W.2d at 59, 37 W.C.D. at 239; Nord, 360 N.W.2d at 342-43, 37 W.C.D. at 372-73.

 

Everest also argues that the injury of September 9, 1996, was not a substantial contributing factor in the employee=s diagnosed chronic pain syndrome.  They argue that the cause of that syndrome and the employee=s disability and continuing need for medical care beyond the four to six months suggested by Dr. Smith is the employee=s injury of June 26, 1996.  Everest points out that Dr. Karen Kane diagnosed signs of chronic pain in the form of depression and anger as early as September 24, 1996.  They emphasize that she suspected at that time already that there were psycho/social factors delaying the employee=s recovery and suggested that the employee may need a consultation with Dr. Clift.  They note that the employee testified that he was frustrated, angry, and depressed at the medical treatment that he had been receiving and that he believed that his return to unassisted work on September 9, 1996, had been premature because of the deconditioned state of his right upper extremity.  They point out that Dr. Clift, in his report of January 22, 1999, stated that, AThe work injury of June 26, 1996 is a substantial contributing cause of Mr. Trossen=s chronic pain syndrome.  There are, in fact, no competing causal explanations for his chronic pain syndrome.@  We are not persuaded.

 

In relating the employee=s chronic pain syndrome to his arm, shoulder, and neck injuries, it is evident that the compensation judge credited the employee=s testimony to persistent pain leading to symptoms of sleep deprivation, protection of the injured right upper extremity, diminished activity level, alteration of activities at home, and greater focus on pain as his primary concern.  Moreover, the employee began viewing his pain as a threat to his continued performance of his job as a sheetmetal worker.  Both Dr. Bensman and Dr. Clift opined that the employee=s symptoms very clearly fit the classic description of a chronic pain syndrome.  The compensation judge=s acceptance of the employee=s testimony and reliance on the opinions of his treating physicians is more than adequately supported by the record.

 

Equitable Apportionment

 

We note first of all that equitable apportionment determinations are based not on any precise formula but on an assessment of all of the facts and circumstances of the case.  Further, equitable apportionment is not purely a medical question but ultimately a question of fact for the compensation judge which does not necessarily require acceptance of any particular medical apportionment opinion.  Ringena v. Ramsey Action Programs, 40 W.C.D. 880, 883 (W.C.C.A. 1987); see also Goetz v. Bulk Commodity Carriers, 226 N.W.2d 888, 27 W.C.D. 797 (Minn. 1975).

 

In the instant case, the compensation judge concluded that the employee=s hand injury of June 26, 1996, and his neck, right shoulder, and right arm injuries of September 9, 1996, were both Asignificant and serious injuries.@  She determined that each injury contributes 50% to the employee=s temporary total disability, temporary partial disability, and need for rehabilitation assistance after September 9, 1996.  A significant component of the judge=s apportionment determination is her conclusion that both injuries are substantial contributing causes of the employee=s chronic pain syndrome.

 

Equitable apportionment is based on the principle that each employer or insurer should be responsible for its proportional share of the employee=s disability.  Goetz, 226 N.W.2d 888, 27 W.C.D. 797.  The liability of an employer or insurer for contribution is, however, dependent on a determination that the employee sustained a compensable injury with that employer or insurer and that that injury is a substantial contributing cause of the employee=s current disability.  Haverland v. Twin Cities Milk Producers Ass'n, 273 Minn. 481, 142 N.W.2d 274, 23 W.C.D. 764 (Minn. 1966); see also Peterson v. O.R. Anderberg Constr., 586 N.W.2d 269, 58 W.C.D. 595 (Minn. 1998).  Everest and Federated both contend that their injury is not a substantial contributing cause of the employee=s disability, as was found by the compensation judge. 

 

Federated argues that, since October of 1996, all of the employee=s symptoms and treatment have been related to the employee=s neck, shoulder, and arm condition.  Dr. Salovich stated that the laceration injury would have been healed nine weeks after it occurred.  At the time of his deposition on February 9, 1999, Dr. Bensman testified that the tendon repair had healed and that the employee=s current symptoms are all symptoms of scalene and trapezius muscle problems and radicular problems related to the employee=s neck.  Dr. Smith stated in his report of November 4, 1998, that the June 26, 1996, injury had resolved without permanent disability.  Dr. Smith testified that the employee=s hand injury was not a continuing factor when he saw him on November 4, 1998.  In his report of August 11, 1998, Dr. Clift reported that the employee=s right hand is sore but functional and that the employee Areports that he is bothered most by constant pain in his right scapular region which is readily aggravated by any repetitive use of his right upper extremity.@  Based on these factors and others, Federated argues that the record does not contain sufficient evidence to establish that the hand injury is a significant contributing cause to the employee=s current disability.  We are not persuaded.

 

In evaluating the severity of the employee=s injuries, it is evident that the compensation judge considered the employee=s physical symptoms following each injury and the length of the period of time between injuries.  In her memorandum, the judge noted that the employee suffered lacerations of tendons in two fingers of his dominant hand.  After surgery, the employee was in a splint and sling for approximately two months.  He was not able to perform any significant work in his trade from the date of his hand injury right up to the date of his second injury on September 9, 1996. The judge further noted that the employee=s right hand and arm were weak and deconditioned from lack of regular use at the time of his September 9, 1996 injury.  She noted that the employee was still undergoing hand therapy through September 1996, and that the hand condition was also a part of the employee=s work conditioning program through February 1997. 

 

The record does not support Federated=s contention that the employee=s hand injury has completely resolved.  As the compensation judge noted, when the employee commenced work hardening following his neck surgery, he experienced a recurrence of his symptoms, including pain and weakness in his right hand.  On March 31, 1998, his occupational therapist reported, AThe client=s main complaints are the decreased strength and instability of the PIP joints with forceful gripping activities.  These functionally limit his tolerance for the forceful tool use tasks and lifting required with his occupation.@

 

The compensation judge further found it important that Drs. Bensman and Clift both found the employee=s right hand injury to be a significant contributing cause of his diagnosed chronic pain syndrome.  Both doctors noted that none of the employee=s chronic pain symptoms existed prior to the work injury of June 26, 1996.  It is evident from the March 31, 1998, note quoted above that the employee=s hand injury continued to play a role in the employee=s ability to return to his occupation.

 

Everest=s contentions relative to the compensation judge=s equitable apportionment determination are essentially based on their previous arguments that any injury that occurred on September 9, 1996, was essentially a consequential injury directly related to the employee=s deconditioned state following his right hand injury of June 26, 1996; that the employee did not sustain a neck injury on September 9, 1996; and that the employee=s chronic pain syndrome was solely related to the employee=s injury of June 26, 1996.  As noted previously, the compensation judge has rejected Everest=s arguments of a consequential injury and has determined that the employee did in fact sustain an injury to his neck on September 9, 1996.  The employee has continued to experience problems with pain and weakness in his right hand, right arm, and right shoulder through the date of hearing on April 2, 1999.  Based on the opinions of Drs. Bensman and Clift, the judge has determined that the September 9, 1996, injury was a substantial contributing cause of the employee=s chronic pain syndrome.  This conclusion was reasonable.  See Nord, 360 N.W.2d at 342-43, 37 W.C.D. at 372-73.

 

We conclude that the compensation judge=s apportionment determination is adequately founded on the employee=s testimony, the mechanism and nature of his injuries, and the medical evidence of record.  While the evidence of record may also have supported the contentions of either Everest or Federated, our role is to determine whether substantial evidence supports the determination of the compensation judge.  We conclude that the compensation judge=s equitable apportionment opinion has reasonable support in the record, and we therefore affirm.  Hengemuhle, 358 N.W.2d at 59, 37 W.C.D. at 239.