The employee appeals from the compensation judge’s finding that her work injury was not a substantial contributing factor in her wage loss and need for medical treatment. We affirm.

Sheri L. Meyers began working for Minnesota Electric Supply Company in January 2005.  By June 2005, she was employed in the warehouse in Coon Rapids in the receiving department.  Her primary duties in that position were to place incoming orders in inventory storage.  Her employer sells electrical parts and equipment to contractors and electricians.

The employee sustained an admitted injury on June 3, 2005.  She was moving boxes from a pallet when she felt sharp pain in her low back and left hip.  The injury was on Friday and the employee reported the injury on Monday.  The next day, June 7, she sought care for her injury.

The employee saw Dr. Jo Theisen at Family Chiropractic on June 7.  She reported pain in the low back and left hip from lifting a heavy box at work.  She rated her pain as nine on a 10-point scale.  Dr. Theisen’s assessment was a lumbosacral sprain/strain, myospasm, hip derangement and thoracic segmental restriction.  Dr. Theisen provided chiropractic adjustments on June 7 and four other dates.  According to the records, the employee did not see Dr. Theisen after June 13.  The chiropractic records indicate the employee had no improvement in her condition and reported low back pain at 9/10 at each visit.

The employee also consulted a medical doctor on June 7, 2005.  She went to Park Nicollet Clinic and saw Dr. Carol Featherstone in the occupational medicine clinic.  The employee reported she was lifting between 150 to 200 pounds when she had the onset of low back pain on the left side.  Examination showed tenderness in the low lumbar spine. No other findings were noted. The employee was provided with medication, work restrictions, and advised to return in one week.  Dr. Featherstone assessed low back pain.^[1]

On June 14, the employee returned and saw Dr. Constance Pries.  She advised Dr. Pries that she had received no improvement from chiropractic care and continued to have low back pain, primarily into the left buttock and left thigh. Examination showed straightening of the lumbar curve. Forward flexion caused increased pain and straight leg raising was positive. Dr. Pries assessed bilateral acute L5 radiculopathy. She took the employee off work and prescribed Percocet to be taken twice daily. An MRI was also recommended.

The employer and its insurer Zurich North America, accepted liability for the June 3 work injury and began paying temporary total disability benefits to the employee.

On June 24, the employee returned to the clinic and saw Dr. John Dunne.  The MRI had been done since the previous visit with Dr. Pries, and Dr. Dunne interpreted the results as showing “desiccation of the disc with minimal diffuse bulges and mildly degenerative disc disease at L2-3.  L5-S1 had desiccation but no herniation or significant mass effect on neural structures.”   Dr. Dunne concluded “this is mostly an acute inflammatory condition.”  He diagnosed “low back pain, mild ligamentous problems” and recommended physical therapy, home exercises and medication.  Dr. Dunne also took the employee off work from June 24 to June 30.  On June 24, the employee also met with a QRC from Zurich who initiated statutory rehabilitation services and accompanied the employee to the appointment with Dr. Dunne.

The employee saw Dr. Pries again on July 1 and reported “no material improvement” in her condition.  Dr. Pries reviewed the MRI and read it as showing no significant abnormalities.  She assessed “low back pain in excess of objective findings.”  Dr. Pries also indicated she would release the employee to part-time light duty.  The employee apparently returned to work for one week and then stopped because she felt too uncomfortable at work.

The employee reported her employment status to Dr. Pries when she returned to see her on July 13.  The employee had been using a TENS unit that helped a little but she had trouble sleeping because of the pain. Examination showed “hypersensitivity to light touch, even of the skin with some centralization in her SI joint.” Dr. Pries assessed “dramatic pain behavior and frustration in the face of a benign examination.  Left S1 strain is likely.”  Dr. Pries recommended an SI joint injection and changed the pain medication to Darvocet.

The employee had the injection on July 18 and went to urgent care on July 24 where she saw Dr. Edwin Funk.  The employee reported that after the injection, the pain got worse and she had nausea and vomiting.  She reported that she had pain into her left leg and foot and that Oxycodone was the only medication that helped.  Dr. Funk did not provide Oxycodone, however, but instead recommended she try Darvocet again.  He also gave her Neurontin and recommended she return to the occupational medicine clinic.

The employee returned to Dr. Funk the next day and stated that the Darvocet had not helped, the pain was worse, and she continued to vomit.  On exam, Dr. Funk found diffuse tenderness in the mid to lower lumbar area of the back and in the left SI joint into the sciatic joint.  He noted the employee did not appear to be in acute distress and had no trouble getting on and off the table. There was no limitation on forward flexion. Dr. Funk gave her Toradol as well as medicine for the vomiting.

Dr. Pries saw the employee again on July 29, 2005.  At that time, the employee said she had not improved from any treatment and was not able to work at all because of her pain.  The exam on that date noted subjective pain with no objective findings.  Dr. Pries stated “I continue to feel that she is not disabled from all work on the basis of her low back complaint, but I increasingly feel that her anxiety disorder may be disabling at this time.”  Dr. Pries recommended a CT scan of the SI joint and asked the employee to return after that procedure.

The CT scan was reported by Dr. Pries, in her August 5 chart notes as showing no acute changes. Bilateral degenerative changes were found.  Dr. Pries stated that the employee’s exam “continues benign” and that “there is no indication for restricted activities once the mental health issues are resolved.”  The employee did not return to Dr. Pries after this visit.

The employee changed QRC’s at this point and began working with Steven Hollander.  The employee also arranged to see a new physician, Dr. Anne Brutlag, in the physical medicine and rehabilitation department.  The employee saw Dr. Brutlag on September 21, 2005.  Dr. Brutlag took a history that the employee had the onset of low back pain at work while lifting a box weighing between 80 to 100 pounds.  The employee identified her pain as being in the low back, right sacroiliac, left buttock, and right thigh.  She said her pain was at eight on a 10-point scale and was worsening.  Dr. Brutlag identified treatment provided previously to the employee as being chiropractic care, heat application, home exercise, cold packs, joint injections, medication, physical therapy, TENS unit, ultrasound, and restriction of activity.  The employee was taking five Percocets per day.  Examination on September 21 showed tenderness in the lumbar spine and bilateral buttock muscles as well as limitation in the range of motion of the lumbar spine.  The employee complained of severe pain with lumbar range of motion.  Dr. Brutlag assessed “low back pain, sacroiliac mechanic dysfunction, possible chip fracture right SI joint.”  Dr. Brutlag recommended physical therapy and kept the employee off work.

At the return visit in October, Dr. Brutlag continued the TENS unit and pain medication and initiated anti-inflammatory medication.  The employee was not released to return to work.  At the time of the November appointment, the employee was noted to have started pool therapy just the day before because of paperwork problems.  Because of the delay in beginning pool therapy, the employee was not released to return to work, and Dr. Brutlag recommended a trial of acupuncture and a pain management consultation.  The employee and her QRC returned to Dr. Brutlag on December 21.  Dr. Brutlag wanted the employee to continue pool therapy despite the flare ups the employee was experiencing.  Dr. Brutlag released the employee to return to work two hours a day for three non-consecutive days per week.  The employee was limited to lifting 10 pounds or less rarely. The employee returned to light duty with the employer on December 23, 2005, and has remained employed on a restricted basis since then.

The employee was seen by Dr. David Boxall on behalf of the employer and insurer on December 28, 2005.  Dr. Boxall concluded that the employee had strained her low back on June 3, 2005.  He deferred much of his opinion until he had received and reviewed medical records.  He noted “evidence of functional overlay manifested by discrepancies on examination.”  He found no evidence of any SI joint injury, since the SI joint injections had not been of any assistance to the employee’s symptoms.

In a subsequent report of April 4, 2006, after he had reviewed the medical records, Dr. Boxall concluded there was no objective basis to place any restrictions on the employee’s work.  It was his opinion that the “history and medical records are consistent with a mild strain of the low back area, which has gone on to be augmented by her, based on the functional overlay and what appears to be seeking of prescription narcotics.”  Based on this report, the employer and insurer filed an NOID to discontinue temporary partial disability benefits.

The employee was evaluated at Park Nicollet in February for consideration of a diagnosis of deep venous thrombosis.  An ultrasound of the right leg appeared to rule out this condition.  An MRI of the lumbar spine was done on March 7, and was interpreted as:

The employee saw Dr. Brutlag again on March 8 with complaints of low back, right buttock and leg pain. She reported that her symptoms had escalated over the past two weeks and were now at a level of eight out of 10.  She had constant pain in her leg with flare ups in the low back and buttocks.  She remained on six Percocet per day and was unable to work more than four to four and one half hours per day.  Dr. Brutlag recommended continued aquatic exercise and continued use of Percocet.  Dr. Brutlag also performed Lidocaine injections in the buttock and in the right trochanteric bursa.  Work restrictions were unchanged.

The employee returned on April 26 and noted no improvement in her condition.  Previous treatment recommendations were continued.  Similar complaints, exam results, and conclusions were noted in the June and August visits with Dr. Brutlag.  On August 2, Dr. Brutlag also stated in her treatment plan that the employee would be referred for possible surgery consideration.  The QRC report of the same date indicated the referral was to Dr. Schwender at Twin Cities Spine Clinic to determine if a fusion of the SI joint was a viable option.

The dispute in this matter was heard by Compensation Judge Harold Schultz II on August 25, 2006.  In his findings and order of September 14, 2006, the compensation judge found that it could not be determined from the record if the employee had sustained more than a low back strain on June 3, 2005, that the lumbosacral strain/sprain suffered on that date had resolved, and that the preponderance of the evidence was that the June 3, 2005, injury was not a substantial contributing factor in the employee’s wage loss and need for medical treatment.  The employee appeals.

On appeal, the employee argues that the compensation judge erred in his decision.  The employee contends that the compensation judge went beyond the record in adopting an opinion that was not supported either by Dr. Boxall or the treating doctors.  We disagree.

The question to be determined in this case by the compensation judge was whether the admitted work injury was a substantial contributing factor in the employee’s wage loss and need for medical care.  While the answer to this question has a medical component, the question is one of fact to be determined by the compensation judge.  The issue is ultimately one of causation.  It is the obligation of the employee to establish by a preponderance of the evidence that there is a causal relationship between the work injury and the claimed benefits.  Fisher v. Saga 463 N.W.2d 501, 43 W.C.D. 559 (Minn. 1990); Trettel v. Cambridge Reg. Ctr., slip op. No. WC04-155 (W.C.C.A. Aug. 5, 2004).  Here, after considering all of the evidence, the compensation judge concluded that the employee failed to establish a causal relationship.  The question for this court is whether substantial evidence exists to support that conclusion.

The employee’s position is that the requisite causal relationship was established by the employee’s treating doctors who “have always listed her injury as work related.”  It is true, as the employee notes in her brief, that on various forms setting out work restrictions, the doctors have marked a box labeling the injury as “work-related.”  Further, in a number of the chart notes form Park Nicollet, the employee’s history that her symptoms began with the work injury is restated.

We agree with the compensation judge that these brief references in the medical records are not persuasive when considering the evidence as a whole.  The question here is not whether there was a work-related physical injury - the employer and insurer agree that there was - or what the diagnosis of that injury might be.  The issue is whether that work-related physical injury continues to be a substantial contributing factor in the claimed wage loss and need for medical treatment.

In this regard, we note that the employee’s first treating doctor, Dr. Pries, concluded on a number of occasions that the employee’s complaints were out of proportion to what were described as “benign” examinations.  Dr. Pries even determined on July 29, 2005, that the employee was not disabled from the work injury and stated in her August 5, 2005, office note that there was no need for restricted activities in the absence of the employee’s anxiety.  Dr. Brutlag, who apparently had a different conclusion, provided no basis for her opinion.  There is no explanation for the difference in opinion between Dr. Brutlag and Dr. Pries and no indication that Dr. Brutlag was aware of the findings and conclusions of Dr. Boxall.

Dr. Boxall’s opinion that the employee needed no restrictions as the result of her work injury also supports the decision of the compensation judge.  While the compensation judge did not accept Dr. Boxall’s diagnosis, a compensation judge need not accept the entire medical opinion in order to rely on part of the opinion.  Proffit v Minnesota Harvest Apple Orchard, 48 W.C.D. 215 (W.C.C.A. 1992); Cloud v Leech Lake Housing Auth., 63 W.C.D. 226 (W.C.C.A. 2002).  Further, as we stated previously, the question is not the diagnosis but the causal relationship between the injury and the claimed disability.  Given the evidence presented by the parties, the determination by the compensation judge that the employee failed to establish a causal relationship between her work injury and her present wage loss and medical treatment is amply supported.

The decision of the compensation judge is affirmed.