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California: Common Mistakes Physicians Make in Their MMI Reports

October 17, 2019 (20 min read)

By Hon. Robert G. Rassp

The opinions expressed in this article are those of the individual author and are not those of the Department of Industrial Relations, Division of Workers’ Compensation or of the WCAB.

The following are three examples of reports from treating and evaluating physicians whose conclusions did not constitute substantial medical evidence. Each flawed MMI report resulted in a workers’ compensation judge’s rejection of a settlement and the requirement that the record be further developed in accordance with McDuffie v. Los Angeles Metropolitan Transportation Authority [(2002) 67 Cal. Comp. Cases 138 (Appeals Board en banc decision)]. These examples are excerpted from the upcoming 2020 Edition of The Lawyers’ Guide to the AMA Guides and California Workers’ Compensation, where a total of ten examples are given. You can pre-order the 2020 Edition today on the LexisNexis Store.

EXAMPLE #1: A long-term assembly worker trips and falls on the employer’s multi-building campus and injured her right arm and shoulder. The diagnosis is right humeral head, proximal humeral head four-part fracture. She has two surgeries: the first one is a SLAP debridement (superior labrum from anterior to posterior, and then a release for adhesive capsulitis or a frozen shoulder. There is no MMI report from a treating physician, so a panel QME is selected through her counsel.

In his physical examination section of the MMI report, the QME states: “Upper extremity motor function shows that deltoid 3 to 4/5, biceps 4/5, triceps 4/5.” He then correctly provides the six ranges of motion of the right injured shoulder. Under his examination section, the QME writes: “Right shoulder strength is 3/5 throughout shoulder girdle.”

Under the section “Impairment Rating,” the QME states: “Flexion 80 degrees, 7% UE Fig. 16-40; Extension 25 degrees, 3% UE, Fig. 16-43, Abduction 80 degrees, 5% UE, Fig. 16-43, Adduction 0% UE, External rotation 1% UE, Fig 16-46; Total 16% UE, conversion table; Table 16-3 10% WPI; chronic pain, add 3% WPI; Grand Total = 13% WPI.”

The QME then states under Future Medical: “Claimant’s right shoulder joint condition is likely beyond the remedial capability of arthroscopic technique. Right shoulder joint pathology may require total shoulder replacement.”

What mistake did this QME make? First of all, the value of the glenohumeral joint is 36% WPI pursuant to Table 16-18. This Applicant is a candidate for a total shoulder replacement based on the QME’s findings. Therefore, a 13% WPI rating empirically is inadequate and inaccurate. What this means is that the panel QME failed to apply Table 16-35, which is manual muscle strength testing along with the range of motion measurements he did find later in his report. He provided the raw data needed to rate the manual muscle strength loss, but he did not carry those objective findings forward to his discussion of permanent impairment. The raw data was provided by the physician and Table 16-35 is easily applied.

The AMA Guides indicate that loss of motion combined with loss of strength should not be combined unless there is a pathophysiological reason to do so that is explained by a physician and the patient is not inhibited from using maximum effort.

In this case, both range of motion and strength loss are applicable because of the severe degeneration of the Applicant’s entire right shoulder joint four years after her specific injury of April 16, 2010. She was examined by the QME in August 2014 by which time the devastating effect of the four-part proximal humeral head fracture with two shoulder surgeries including a SLAP debridement and release of adhesive capsulitis after a frozen shoulder joint had occurred. The Applicant had multiple fractures of her humeral head with post-traumatic arthritis and changes to her glenohumeral joint. This involves separate pathophysiological causes that resulted in her loss of strength and loss of shoulder motion.

Accordingly, the Applicant has the following permanent disability based on a review of the entirety of the QME report:

Based on the conclusions of the QME as to loss of range of motion:

Right shoulder Flexion 80 degrees: 7% UE

Extension 25 degrees: 3% UE

Abduction 80 degrees: 5% UE

Adduction normal: 0% UE

External Rotation: 1% UE

Internal Rotation: 0% UE

Total UE for loss of motion: 16% UE

Grade 3/5 muscle strength testing Table 16-35:

Flexion: 30% of 24 UE = 7% UE

Extension: 30% of 6 UE = 2% UE

Abduction: 30% of 12 UE = 4% UE

Adduction: 30% of 6 UE = 2% UE

Internal Rotation: 30% of 6 UE = 2% UE

External Rotation: 30% of 6 UE = 2% UE

Total UE for muscle strength loss: 19% UE

19% UE strength loss combined 16% UE range of motion = 32% UE = 19% WPI plus 3% for pain related impairment = 22% WPI.

The final rating is as follows: – 19 + 3% pain = 22 – [7] 30 – 221F – 30 – 35% Final PD

The original rating was only 10% WPI for the range of motion loss, plus 3% WPI for pain related impairment. The more accurate rating is 22% WPI that includes the 3% WPI pain add-on. Counsel should be aware that the loss of motion and manual muscle strength ratings are in UE and then combined using the CVC, then converted to WPI, then the 3% WPI pain add-on is added to the 19% WPI. This rating is based on the 2005 permanent disability rating schedule instructions on page 1-11, which states in part:

Multiple impairments such as those involving a single part of an extremity e.g. two impairments involving a shoulder such as shoulder instability and limited range of motion, are combined at the upper extremity level, then converted to whole person impairment and adjusted before being combined with other parts of the same extremity.

The justification of the 3% WPI pain add-on included consideration for the fact that the Applicant was severely restricted by the QME to the use of her right dominant arm. He stated she is limited to: “semi-sedentary work; Right arm usage limited to light lift, less than 10 pounds and elevate shoulder to less than 80 degrees.”

There are multiple takeaways in this example since shoulder impairments are complex and physicians do not carry over many objective ratable findings to the discussion of permanent impairment. Also, make sure physicians use upper extremity measurements for the range of motion and other upper extremity disorders and do not mix them up with WPI ratings for the same part of body.

EXAMPLE #2: 55-year-old packer for a glass manufacturer had a 3400-pound steel frame loaded with glass panels run over his left foot, resulting in a dislocated great toe. The Applicant had surgery to fuse the great toe’s first interphalangeal joint [IPJ] with a reconstruction of the metatarsophalangeal joint [MPJ]. One year after the surgery, he returned to work, wearing an orthotic device on his left foot. In the MMI report from the treating podiatrist, it is noted that the Applicant walks with an “antalgic gait.” A walk-through Stipulations With Request for Award was submitted to a judge for approval with a 0% permanent disability.

In his rejection of the 0% permanent disability proposed settlement, the judge indicated in the Order Suspending Action on the settlement that the treating physician’s report “does not provide an evaluation for the gait impairment pursuant to Table 17-5 or any other alternative rating for a dislocated great toe on the left foot that has a surgically fused joint.” The judge recommended that the Applicant obtain an opinion from a panel qualified medical evaluator in accordance with Labor Code § 4062.1, the procedure for an unrepresented injured worker to obtain such an evaluation,

In fact, the Applicant did select a panel QME in podiatry and the QME listed the following objective findings on examination: “Ankylosis and arthritis 1st IPJ, hallux limitus 1st MPJ, muscle weakness, atrophy calf, and gait derangement.” The QME report has a very detailed description of the Applicant’s residual left foot conditions as a result of this very serious injury. The report constitutes substantial medical evidence and can be a model for any foot or ankle injury case. The QME’s description of how and why he came up with a 10% WPI overall impairment rating is worth reading:

The Applicant has paresthesia beginning at the anterior left ankle to the dorsum of his toes. Furthermore, he states he has paresthesia from the proximal 1st through 5th MPJ region distal to the tips of 1st through 5th toes. There was no pain with range of motion to the left 1st IPJ but there is complete ankylosis to the joint with no motion, There was mild pain with range of motion with dorsiflexion to the right 1st MPJ but the joint motion is limited. That does not coincide with an arthritic joint causing pain to the 1st IPJ necessitating a fusion, But it is reasonable why he would be having pain at the 1st MPJ due to hallux limitus and jamming of the MPJ with dorsiflexion of the joint. It also makes sense why he had a steppage gait and avoids a normal heel to toe gait, therefore avoiding dorsiflexion of the 1st MPJ. His left foot is supinated and inverted because he is avoiding pressure to the medial forefoot. Therefore, he may have a nerve compression injury to the dorsal digital (superficial dorsal cutaneous) and plantar digital (medical plantar) nerves. His gait is altered secondarily because of muscle weakness, limited range of motion to the 1st MPJ, no motion to the 1st IPJ, and possible nerve pain.

Under objective factors, the QME stated: “Ankylosis and arthritis 1st IPJ, hallux limitus 1st MPJ, muscle weakness, atrophy calf, and gait derangement.” The QME utilized range of motion, ankylosis, and atrophy from pages 530-552 and Tables 17-14, 17-30, 17-6 and 17-37 as follows:

Pages 533-538 and Table 17-14, range of motion toe impairment. The left 1st MPJ has mild limited range of motion rated at 1% WPI and the 1st IPJ (moderate to severe) o degrees range of motion rated at 2% WPI.

Pages 538-543 and Table 17-30, joint ankylosis toe. The 1st MPJ and IPJ have ankylosis with rating of 4% WPI.

Pages 530-531 and Table 17-6, muscle atrophy as measured to the calf with the right larger by 1 cm, rated at 1% WPI.

Pages 550-551 and Table 17-37, peripheral nerve injury, the medical plantar nerve to the great toe with rating 2% WPI.

Therefore, the total impairment rating is summed to (1+2+4+1+2) = 10% WPI, all based on the objective findings on examination.

The DWC Disability Evaluation Unit (DEU) rated the above factors as follows:

Left Greater Toe ROM/Ankylosis 10 C5 C 2 = 17 LE = 7% WPI – 7 – [1.4] 10 – 460H – 13 – 16 PD (A)

Left Calf Atrophy: 3 LE = 1% WPI – 1 – [1.4] 1 – 460F - 1 – 1 PD (A)

Left Medical Plantar Nerve – Peripheral Nerve: 5 LE = 2% WPI – 2 – [1.4] 3 – 460H – 5 – 6 PD (A)

(A) 16 combined 6 combined 1 = 22% Final Permanent Disability

This case illustrates a number of things. Number one, it raises the question of how many cases like this slipped through the cracks and resulted in a 0% or extremely low permanent disability award if the judge was not paying attention to the medical evidence behind a proposed Award? This case was presented for approval by a judge on a walk-through basis. Number two, this case also illustrates that physicians are reluctant to use Table 17-2, the cross-usage chart that prevents pyramiding impairments such as “diagnosis based” with “atrophy.” The QME in this case simply stated that using the cross-usage chart was not accurate in describing the devastating effect this injury has on the Applicant’s ability to ambulate. Number three, this QME did not use station and gait impairments from Table 13-15 in Chapter 13, nor antalgic gait of up to 7% WPI from Table 17-5 since he felt the objective findings added up to more specific and more accurate impairment ratings. This case, after all, is a great toe injury and does not involve the entire foot or ankle.

EXAMPLE #3: A 27-year-old dishwasher at a restaurant on 11/14/13 lifts a heavy bin of dishes and has the acute onset of low back pain. Within one week, he retains counsel who sends him for treatment with a chiropractor. The chiropractor’s MMI report rates 47% WPI while a panel QME in orthopedic surgery rates a 5% WPI. Both physician reports are wrong. Why?

The Chiropractor’s MMI report includes some of the following factors:

The Applicant has normal gait; Sensation is decreased in the right lower extremity over the L4-S1 dermatome; Motor strength is decreased in the left quadriceps, hamstrings, tibialis anterior, peroneus longus, and extensor hallucis muscles (L4-S1 dermatomes); motor strength is decreased in the right peroneus longus and extensor hallucis muscles (L5-S1 dermatomes); Knee jerk and Achilles reflexes are decreased bilaterally.

Left Straight Leg Raise ranges to 10 degrees with pain radiating to the buttock; Right Straight Leg Raise ranges to 12 degrees with pain radiating to the buttock. Range of motion measurements are:

Lumbar Flexion: 12 degrees (Normal is 60+ degrees) WPI = 8%

Lumbar Extension: 9 degrees (Normal is 25 degrees) WPI = 5%

Lumbar Left lateral bend: 12 degrees (Normal is 25 degrees) WPI = 3%

Lumbar right lateral bend: 15 degrees (Normal is 25 degrees) WPI = 2%


Under Table 15-7 spinal disorders, he has disc herniations at two levels with degenerative changes and radiculopathy which is 7% plus 2% WPI under Sections IIC and IIF of Table 15-7.


He has radiculopathy in both lower extremities at multiple levels, under Tables 15-15-, 15-16, 15-18 he has Grade 4, 25% sensory and motor deficits at each level of L4, L5 and S1; with 9% LE, 9% LE, 5% LE for the left lower extremity; and a 25% sensory and motor deficits at each level of L4, 5, and S1 with 1% LE, 1% LE, 9% LE, and 5% LE for the right lower extremity. This totals 17% LE which is a 7% WPI.



L3-L4 broad based disc protrusion which causes stenosis of the canal; disc measurements are neutral 5.4 mm, flexion 2.7 mm, extension 2.7 mm;

L4-L5: Broad based disc protrusion which causes stenosis of the spinal canal

There is associated stenosis of the bilateral lateral recess with deviation of the visualized bilateral L5 transiting nerve roots. Neutral 4.0 mm, flexion 5.4 mm, extension 5.4 mm.

L4-L5 (sic) Broad-based disc protrusion which causes stenosis of the spinal canal. There is associated stenosis of the bilateral lateral recess with deviation of the visualized bilateral S1 transiting nerve roots. Neutral 4.0 mm, flexion 5.4 mm, extension 5.4 mm.

2/5/14 X-ray of the lumbar spine [by a reputable radiologist] reveals “Normal lumbar spine examination with no subluxation on flexion and extension.

3/10/13 CT of the lumbar spine [also from a reputable radiologist]:

L3-4: 1-2 mm posterior disc bulge without evidence of canal stenosis or neural foraminal narrowing;

L4-5: 2-3 mm posterior disc bulge resulting in mild left neural foraminal narrowing; left facet joint has vacuum effect;

L5-S1: 3-4 mm posterior disc bulge resulting in mild right and mild to moderate left neural foraminal narrowing, mild canal stenosis,

4/4/14 EMG/NCV: Normal studies of the lower extremities with no acute or chronic denervation; no electrophysiological evidence of peripheral nerve entrapment.

The chiropractor then goes through two pages of his report applying the pain related impairment criteria in chapter 18 of the AMA Guides and goes through all of the activities of daily living criteria in Table 1-2 of the Guides and concludes there should be a 3% WPI pain add-on. The chiropractor goes on to apply an Epworth Sleep Study and puts the Applicant into a Class I of Table 13-4 and assigns a 5% WPI rating for a sleep disorder. He also adds another 8% WPI for emotional and behavioral impairments based on Table 13-4 of the Guides. He justifies doing the foregoing based on the “Almaraz Guzman case for a more accurate WPI rating.” The chiropractor also concluded there is no apportionment of permanent disability to non-industrial factors.

The chiropractor’s summary of impairments is:

Lumbar disc herniations at L4-5 and L5-S1 with degenerative changes: 9%

Lumbar spine loss of motion: 18%

Left lumbar radiculopathy (decreased motor strength): 8%

Right lumbar radiculopathy (decreased motor and sensation): 7%

Limitation of daily social and interpersonal functioning: 8%

Sleep impairment: 5%

Pain related impairment: 3%


This example is valuable because it assists counsel in finding the red flags that indicate specific problems with medical reports and to more closely scrutinize a physician’s conclusions. The context of this report is that it was submitted to a trial judge at trial. A report from a panel QME in orthopedic surgery was also submitted into evidence, and this doctor concluded that the Applicant’s lumbar spine injury is MMI with a DRE Category II 5% WPI and no apportionment of permanent disability to non-industrial factor. The trial judge asked another judge to read the treating physician’s report because the trial judge felt there was “something fishy” about the chiropractor’s report. What are the telltales of the red flags?

There are a number of factors that caught the attention of the reviewing judge. At the time of the MMI exam by his chiropractor, the Applicant was 28 years old (he was 27 on the date of injury), 5’11” and 266 pounds, which is about 70 pounds overweight. The second red flag was the physical examination section of the MMI report. The chiropractor indicated that the straight leg raising (SLR) test was positive at 10 degrees with the left leg and 12 degrees with the right leg. This is pure nonsense. A straight leg raise test is a very reliable test to determine if there is irritation of the sciatic nerve distribution from a herniated disc or other nerve compression phenomenon. Usually, with a frank disc herniation, the SLR is strongly positive at 60 degrees or more. A proper SLR test will follow the illustration on page 405 of the Guides. In addition, a proper examination would include both a supine SLR test and a sitting SLR test where the patient is sitting on the edge of an examination table and the physician brings the patient’s leg from a gravity assisted level (the legs dangling off the table with the knees bent) to 90 degrees of extension for each leg. This result should be the exact same as for the supine SLR. SLR testing is a gold standard to prove the existence of nerve root irritation in clinical medicine and in social security disability cases involving the lumbar spine.

The next red flag in this case was the chiropractor’s finding of muscle weakness and motor strength deficits for lower extremity dermatomes. The nerve conduction and EMG studies were normal. When there is a sensory and motor deficit as bad as this doctor claims there is, the electrophysiological testing would also be positive, especially when there is motor function impairment. The rule with nerve compression phenomenon is that sensory deficits occur first, then motor deficits if there is nerve damage. Once there are motor function deficits, then the nerve damage is permanent. An example of this is a person who has developed “drop foot”, which is evidence of permanent nerve damage along the sciatic-tibial-peroneal nerve distribution.

The next red flag is the MRI scan results for the lumbar spine. The MMI report “summarizes” the findings of the radiologist who purportedly read the MRI for the lumbar spine. What indicates that the MRI conclusions are bogus are the results of the CT scan that is discussed later in the MMI report. The MRI scan was performed less than 90 days from the date of injury. There is no way the degenerative changes mentioned in the MRI report is post traumatic. Usually with an acute injury such as what occurred in this case (the Applicant lifting a heavy bin of dishes), there would be one level of the spine, usually L4-L5 or L5-S1 that would show a herniation or disc bulge. There was nothing like that in this MRI.

The other problem with the MRI report is the radiologist indicating how many millimeters the “disc measurements” are. This is pure nonsense as well. The average diameter of the lumbar spinal canal is 13 mm. The statement for example that at L4-L5 the disc measurements are “neutral 4.0 mm, flexion 5.4 mm and extension 5.4 mm” is utter nonsense. It is hard to believe that flexion-extension MRI scanning was even performed. In fact, the gold standard to see if a patient has spondylolisthesis is to perform flexion-extension x-rays and not an MRI scan. A credible x-ray of the lumbar spine by another radiologist found no evidence of subluxation on flexion and extension x-rays. If the MRI radiologist is referring to what diameter of the lumbar spinal canal is remaining due to spinal stenosis, anyone with 4.0 mm or 5.4 mm left in the spinal canal space would have extreme difficulty to walk or bend. That type of spinal canal stenosis would require an emergent neural foraminal and central canal decompression surgery.

What gives this case away the most is the result of the CT scan of the lumbar spine which was conducted by a credible radiologist. The CT scan indicates that the Applicant has a 1-2 mm bulge at L3-L4, a 2-3 mm at L4-L5, and a 3-4 mm bulge at L5-S1. There is no frank nerve root impingement phenomenon. These findings are not unusual for a 27-year-old man who engages in heavy work and who is 70 pounds overweight. Expressed a different way, these findings are within normal limits for a man of this body habitus and age. The reference to “vacuum phenomenon at the facet joint” means the facet joint is degenerating, but the Faber test for

sacroiliac pain was negative.

Another red flag for this report is the fact that the chiropractor claimed to utilize Almaraz-Guzman to include ratings for a sleep disorder using Table 13-4 and for a psychiatric impairment using Table 13-8. What the chiropractor did not mention is that the date of injury in this case is in 2013, which makes this case subject to the restrictions of Labor Code § 4660.1(c)(1) and there is no evidence that the injury was from a violent act or a catastrophic injury. The only catastrophe is the lack of credibility of this MMI report.

Of major concern about this MMI report is that the chiropractor made the report look very authoritative, authentic, and comprehensive. It is clear that the doctor has a significant knowledge of the AMA Guides, but he dishonestly applies them in a case that may rate at the most a 13% WPI if the Applicant falls within a DRE III lumbar spinal impairment rating, which is most likely.

On the other hand, the trial judge is faced with a panel QME report that rates a DRE Category II 5% WPI, which is actually the equivalent of a severe back sprain with some positive findings on the imaging testing, probably the CT scan at L5-S1 for the 3-4 mm disc bulge. The PQME opined that the Applicant does not have a radiculopathy at the time of his MMI examination, which places the case within a DRE Category II. The PQME did not perform a range of motion analysis of the case, probably because he does not know how to. This is because of language he used in his report, that says the DRE method rates higher in this case than the Range of Motion method. Remember, that is a red flag, that the PQME does not know how to perform the 12 steps of the ROM method for the lumbar spine.

Therefore, is this case a 47% WPI or a 5% WPI? The best friend of a workers’ compensation trial judge is McDuffie v. Los Angeles Metropolitan Transportation Authority [(2002) 67 Cal. Comp. Cases 138 (Appeals Board en banc decision)]. In many cases including this one, the trial judge has to develop the record. In this case, the trial judge vacated submission of the case for decision, ordered the parties to a further hearing, and requested that the parties agree to an agreed medical examiner in orthopedic surgery. Failing an agreement to use an AME, the judge will order a regular physician pursuant to Labor Code § 5701, which will result in an agreed medical examiner quality physician to sort this case out.

The other glaring problem with the treating physician’s MMI report is that this Applicant is not a surgical candidate. How can a low back injury result in a 47% WPI rating when there was no surgery? That red flag can be seen by anyone who reviews this report.

© Copyright 2019 LexisNexis. All rights reserved. This article is excerpted from The Lawyer’s Guide to the AMA Guides and California Workers’ Compensation, 2020 Edition. Pre-order the 2020 Edition today on the LexisNexis Store.