Upper Extremities Peripheral Nerve Disorders

¬Impairment & Disability Rating Specialists®

California Workers Compensation

Craig Andrew Lange

A P&S Report Checklist

[L.C. 139.2 (J)-(2)&(3), (k)-(5), 4060(b)(1), 4062 (d)(2), 4068,8 CCR WCAB 10606) 8 CCR 9785]

Upper Extremities Peripheral Nerve Disorders Impairments (PND)

For Article in Adobe Format Click Here: UEPND.pdf

It is the purpose of the AMA Guides to be used for the consistent and reliable acquisition of medical information, through a single set of standards. When clinical findings are fully described, any knowledgeable observer may check the findings with the Guides criteria and determine the proper calculation of impairment. - AMA 5th Ed, Chapter 1, pages 10 & 11.

Rating Carpal Tunnel Syndrome- AMA 5th Ed, p 495.

1. Impairment Rating of Entrapment/Compression Neuropathies - AMA 5th Ed., pages 493 to 495

1.1. Proper clinical examination and calculation of impairment for post-surgical carpal tunnel syndrome is addressed is this section.

2. AMA 5th Ed., page 495: “...following surgical decompression 3 following scenarios can be present:

2.1. Positive clinical findings of median nerve dysfunction and electrical conduction delays(s) are rated according to sensory/motor deficits. Peripheral Nerve Disorders Impairment: - AMA 5th Ed., pg 480.

2.2. Residual Carpal tunnel syndrome is still present – impairment of 05% UEI may be justified.

2.3. Normal clinical findings, including 2-point discrimination – no objective basis for an impairment rating.

2.3.1. Evaluating Physician is warned not to combine Section 16.5 Impairments with grip and pinch Impairment values from Section 16.8 - AMA 5th Ed., pg 507.

3. AMA Guides requires that physician, before estimating the extent of an impairment, establish an accurate diagnosis. The primary requirement is the confirmation of the presence or absence of specific pathology or loss of organ function. Neurodiagnostic studies are an integral part of this process. Neurodiagnostic testing is essential as an adjunct to the clinical examination in order to determine the diagnosis on which the impairment is based. Electrodiagnostic tests can be necessary to localize neurologic lesions affecting the peripheral nerves. AMA, Disability Evaluation, pages 442 - 445. AMA 5th Ed, pg 480.

3.1. The simple determination of a diagnosis is not sufficient to assess the level of impairment or disability. Electrodiagnostic Testing is necessary in order to document the degree of neurologic deficit.

Board Certified Technician In Electromyography.

4. The AMA Guides requires objective verification and confirmation of subjective complaints and that neurodiagnostic testing has been advocated to confirm these subjective complaints. The Guides recommends that technician be certified by The American Board of Electrodiagnostic Medicine and that the testing be done in an environment, meeting the guidelines of the American Association of Electrodiagnostic Medicine. Unequivocal electrodiagnostic evidence of acute nerve root pathology includes the presence of multiple positive sharp waves or fibrillation potentials in muscles innervated by one nerve root. However, the quality of the person performing and interpreting the study is critical. Only a licensed physician qualified by reason of education, training and experience in these procedures should perform electromyography. AMA Disability Evaluation pg. 459: - AMA Guides, pgs. 18, 307, 382 & 493

4.1. “Nerve conduction and needle electromyography (EMG) studies help to determine which nerves are involved and their anatomic location. Also evident will be whether sensory, motor, or both fibers are predominantly involved and whether axonal degeneration, deymelination, or a combination of both is present. Skillful differentiation of peripheral neuropathy and neuromuscular disorders may also be possible. Expert neuromuscular knowledge and understanding of pathologic manifestations of disease processes are necessary for the appropriate application and performance of these tests, particularly the EMG. These tests are objective and require minimal cooperation from the individual being tested. They reflect pathology in the largest, fastest-conducting nerve fibers. The interpretation of these tests must be correlated with a detailed neurologic evaluation. AMA Guides, pg. 307.

4.2. “It must be remembered that many abnormalities found on neurologic examination are subjective. Except in the most obvious cases, the task of delineating the presence and extent of a suspected abnormality is heavily dependent on electrodiagnostic procedures. Electromyography and nerve conduction studies provide objective evidence of nerve injury. Electromyography demonstrates objective evidence of denervation in conditions affecting motor nerves. Nerve Conduction Studies reveal abnormalities in conditions causing significant axonal loss or demyelination of the peripheral nerves. As with most tests, (Clinical studies -AMA 5th Ed, pg 378 & 382) obtained results must be correlated with the findings from clinical examination. Once the exact anatomic location, type of tissue involved and severity of the neuropathy is determined, the maximum percentage of lost function due to weakness or loss of sensation can be estimated.”

4.3. Quantitative sensory tests are portable tests, easily conducted in the clinician's office, which provide a quantitative assessment of sensation. These tests can provide information about nerve fibers not examined by nerve conduction studies. . For Entrapment Neuropathies, ‘slowing of conduction’ is the chief finding of The Nerve Conduction Studies. - – AMA Disability Evaluation, page 466

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Upper Extremity PND Impairments: P&S Report Checklist

Luis Pérez-Cordero

¬Impairment & Disability Rating Specialists®

California Workers Compensation

Craig Andrew Lange

AMA 5th Ed, pg 488, Figure 16-48 / AMA Disability Evaluation, pg 488, Figure 35-2

5. In order to give an impairment rating, objective, reproducible physical findings or objective abnormalities on needle electrodiagnostic testing have to be present in the clinical examination. Complaints of pain, loss of sensation or loss of strength in the defined pathway of a nerve, without objective evidence of an injury to the peripheral nervous system (PNS), do not receive any impairment. AMA Disability Evaluation, page 482.

5.1. In order to receive a permanent impairment, the complaints of pain and loss of sensation have to be consistent, reproducible, and in the defined anatomic pathway of the spinal nerve, brachial plexus or major peripheral nerve that is diseased. AMA 5th Ed, Impairment Determination Method, pg 481

5.2. “The pathology that affects the PNS produces signs and symptoms in the extremities that are specific to the level of area of injury.” Only unequivocal and permanent sensory deficits are given permanent impairment ratings. Lesions of an individual nerve produce symptoms and signs in the distribution of the involved nerve. AMA 5th Ed – Section 16.3 pgs 445, 446 & Section 16.5. pg 480 & AMA Disability Evaluation, pg. 481

Click link below to see Upper Extremity Peripheral Nerve Distribution

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Upper Extremity PND Impairments: P&S Report Checklist

Luis Pérez-Cordero

¬Impairment & Disability Rating Specialists®

Craig Andrew Lange

To Rate Impairment, Neuropathy needs to be present On The Date Of Examination For The MMI/P&S Report.

ü Entrapment/compression neuropathies are rated when an objective verifiable diagnosis is present, supported by positive clinical findings and loss of function. AMA 5th Ed., 493

1. Upper extremity impairments due to sensory deficits or pain resulting from peripheral nerve disorders are determined according to the grade of severity in diminution or loss of function and the relative maximum upper extremity impairment value of the nerve structure involved, as shown in the classification (a) and procedural (b) steps described in Table 16-10 and the impairment determination method detailed in Section 16.5b. Table 16-10 is to be used for pain that is due to nerve injury or disease that has been documented with objective physical findings and/or Electrodiagnostic abnormalities. AMA 5th Ed, pg 482:

2. Nerve conduction and needle electromyography (EMG) studies help to determine which nerves are involved and their anatomic location. Skillful differentiation of peripheral neuropathy and neuromuscular disorders may also be possible. Expert neuromuscular knowledge and understanding of pathologic manifestations of disease processes are necessary for the appropriate application and performance of these tests, particularly the EMG. These tests are objective and require minimal cooperation from the individual being tested. They reflect pathology in the largest, fastest-conducting nerve fibers. The interpretation of these tests must be correlated with a detailed neurologic evaluation. AMA 5th Ed, pg 307

Median Nerve Neuropathy – Carpal Tunnel Syndrome
AMA Guides Clinical & Rating Criteria (Substantial Medical Evidence Standards)	Yes Ö	No Ö	Reported Medical Findings Med Rpt., pgs.
1. For maximal recovery of nerve function of nerve lesions at the wrist, have 6-9 months past?
2. Have Physician commented on employee’s demeanor, general behavior, mannerisms during interview/history taking?
3. Any indications of abnormal movements?
4. Does the examination include observations of muscle bulk (looking for atrophy), muscle tone, deep tendon reflexes and strength?
5. Are prior symptoms and complaints corresponding to the sensory and motor distribution of the median nerve?
6. Testing Standards: AMA 5th Ed, pg. 10, 307, 493 & AMA Disability Evaluation page 459
6.1. Diagnosis confirmed by electrodiagnostic studies (needle & cutaneous) as well as sensory and motor nerve conduction studies conducted by a Board Certified Neurologist (with appropriate training)?
6.2. Testing Area has met required standards?
7. Nerve Conduction Velocity Test (Nerve Conduction Study) measures how quickly electrical impulses move along a nerve. It is often done at the same time as an electromyogram, in order to exclude or detect muscle disorders.
7.1. Were motor and sensory latencies, conduction velocities, H reflex & F wave properly evaluated?
7.2. Decreased Amplitudes?
7.3. Results of Sensory NCS?
7.4. Results of Motor NCS?
8. Has physician tested all the muscles of the upper extremities, tested sensation and reflexes?

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Upper Extremity PND Impairments: P&S Report Checklist

	Luis Pérez-Cordero pdrating@pacbell.net	¬Impairment & Disability Rating Specialists® http://www.pdratings.com/				Craig Andrew Lange craigalange@pacbell.net
Median Nerve Neuropathy – Carpal Tunnel Syndrome
AMA Guides Clinical & Rating Criteria (Substantial Medical Evidence Standards)			Yes Ö	No Ö	Reported Medical Findings Med Rpt., pgs.
9. Electromyogram (EMG) is a test that measures the electrical activity of a muscle. It detects any signs of blocking or slowing down of responses to nerve stimulation. The test provides information about the muscle itself and shows how well it receives stimulation from the nerve. (A nerve conduction velocity (NCV) test is often done at the same time as an EMG.)
9.1. Is EMG indicative of median neuropathy?
9.2. Is the contralateral asymptomatic or symptomatic for median neuropathy?
9.3. Does the EMG provide objective evidence to support the symptoms and findings- confirmation of carpal tunnel syndrome?
9.4. Degree of median nerve involvement identified as per the electrodiagnostic studies?
9.5. Is the injury to the nerve complete or partial?
10. Have both the Nerve Conduction Studies / EMG tests ruled out other pathologic nerve compression?
10.1. Is the EMG indicative of non-vocational underlying polyneuropathy?
10.2. Cervical radiculopathy?
11. Evaluator properly addressed predisposing (pre-existing) non-vocational causation factors?
11.1. Evaluator apportions to pre-existing/predisposing or associated conditions such as diabetes, arthritis, alcoholism, renal disease, hormonal changes, malnutrition, obesity, alcohol abuse, systematic neurologic disorders/diseases or hypothyroidism? AMA 5th Ed, pgs 480 & 491)
Impairment Determination Method – AMA 5th Ed, pg 481
12. Evaluator properly Identifies the portion of the (injured) medial nerve involved (anatomic distribution) if sensory deficits/pain is present?
13. Evaluator examined all muscle groups, identifying which are weak If motor deficits or loss of power is present?
14. Are symptoms (numbness, tingling, etc.) present on the palmar surface of the 3½ radial digits innervated by the median nerve? (See Chart on Page 2)
15. Clinical Neurological Evaluation and ancillary clinical testing have been correlated to the electromyographic studies? (One or more of the tests used to reproduce symptoms is positive.)
15.1. Tinel Sign?
15.2. Phalen’s Test?
15.3. Median Nerve Compression Test
16. Evaluation of 2-Point Discrimination Testing on the pulp of all the digits for both hands? AMA 5th Ed, pg 449
17. Type of sensory loss for innervated median nerve fingers?
17.1. (£) 6^mm (Normal)
17.2. 7-15^mm (50% Loss) Abnormal
17.3. Greater than (>) 15^mm (100% Loss) Abnormal
18. Physician addresses the type of sensory loss for other digits?

Page 4 of 6

Upper Extremity PND Impairments: P&S Report Checklist

Luis Pérez-Cordero

¬Impairment & Disability Rating Specialists®

Craig Andrew Lange