ADJ10247229 · September 13, 2022

Dr. Angerman's apportionment opinion was not substantial evidence because it lacked explanation of the nature and causation of the pre-existing condition; the record lacked substantial evidence for final determination; the case was remanded for further development and supplemental report from Dr. Angerman.

From the decision · page 5As noted above, in his reports. Dr. Angerman discussed apportionment in the context of "the subtraction method." He concluded that if the subtraction method (i.e. the section 4664(b) presumption) was not applicable, then, "... [I]n all medical probability, 80% of the patient's left ankle disability/impairment would be attributable to her prior stipulated injuries." (Joint Exh. AA, p. 42.) Dr. Angerman did not describe the nature of the pre-existing condition. Nor did he explain how and why the prior injuries were causing permanent disability at the time of the evaluation, or how and why the prior injuries were responsible for 80% of applicant's left ankle disability. Therefore, his opinions do not comply with the requirements of the applicable case law and they do not constitute substantial evidence as to the issue of apportionment. (Acme Steel v. Workers' Comp. Appeals Bd. (Borman), supra; Escobedo v. Marshalls, supra.)

Dr. Angerman's apportionment opinion lacked explanation of the nature and causation of the pre-existing condition and did not comply with case law requirements for substantial evidence.

Favours Applicant prevailed

This led to rejection of the apportionment opinion and remand for further proceedings to develop the record and obtain a proper medical opinion.

From the decision · page 5As noted above, in his reports. Dr. Angerman discussed apportionment in the context of "the subtraction method." He concluded that if the subtraction method (i.e. the section 4664(b) presumption) was not applicable, then, "... [I]n all medical probability, 80% of the patient's left ankle disability/impairment would be attributable to her prior stipulated injuries." (Joint Exh. AA, p. 42.) Dr. Angerman did not describe the nature of the pre-existing condition. Nor did he explain how and why the prior injuries were causing permanent disability at the time of the evaluation, or how and why the prior injuries were responsible for 80% of applicant's left ankle disability. Therefore, his opinions do not comply with the requirements of the applicable case law and they do not constitute substantial evidence as to the issue of apportionment. (Acme Steel v. Workers' Comp. Appeals Bd. (Borman), supra; Escobedo v. Marshalls, supra.)

Applicant had 12% whole person impairment from left ankle ankylosis; apportionment opinion that 80% of left ankle disability was from prior injuries was not substantial evidence due to lack of explanation.

Dr. Angerman did not describe the nature of the pre-existing condition or explain how it caused disability or why it was responsible for 80% of the disability, failing to meet case law requirements for substantial evidence on apportionment.

From the decision · page 2Dr. Angerman was provided additional medical records and in his supplemental report he concluded that applicant had 12% whole person impairment (WPI) as a result of her left ankle ankylosis [stiffness or fixation of the joint]. (Joint Exh. AA, Dr. Angerman, April 11, 2018, pp. 43 § 44.) Regarding apportionment, Dr. Angerman stated:

Kopping v. Workers' Comp. Appeals Bd. (2006) 142 Cal.App.4th 1099

Labor Code 4664(b) conclusive presumption affecting burden of proof for apportionment

Employer must prove prior permanent disability exists and overlaps with current disability to avoid liability for overlapping disability.

From the decision · page 3Regarding the section 4664 presumption, the Third District Court of Appeals explained:

Acme Steel v. Workers' Comp. Appeals Bd. (Borman) (2013) 218 Cal.App.4th 1137; Escobedo v. Marshalls (2005) 70 Cal.Comp.Cases 604 (Appeals Board en banc)

Apportionment of permanent disability must be based on causation and supported by medical opinion with reasoning

Medical opinion on apportionment must explain nature of pre-existing condition and how it causes disability to be substantial evidence.

From the decision · page 4To be substantial evidence on the issue of apportionment a medical opinion must set forth reasoning in support of its conclusions. For example, if a physician states that a percentage of an injured worker's disability is caused by a pre-existing condition, the physician must explain the nature of the pre-existing condition, how and why it is causing permanent disability at the time of the evaluation, and how and why it is responsible for the percentage of the disability identified by the doctor. (Acme Steel v. Workers' Comp. Appeals Bd. (Borman) (2013) 218 Cal.App.4th 1137 [78 Cal.Comp.Cases 751]; Escobedo v. Marshalls (2005) 70 Cal.Comp.Cases 604 (Appeals Board en banc).)

Dr. Angerman's apportionment opinion lacked explanation of the nature and causation of the pre-existing condition, failing to meet substantial evidence standards.

From the decision · page 5As noted above, in his reports. Dr. Angerman discussed apportionment in the context of "the subtraction method." He concluded that if the subtraction method (i.e. the section 4664(b) presumption) was not applicable, then, "... [I]n all medical probability, 80% of the patient's left ankle disability/impairment would be attributable to her prior stipulated injuries." (Joint Exh. AA, p. 42.) Dr. Angerman did not describe the nature of the pre-existing condition. Nor did he explain how and why the prior injuries were causing permanent disability at the time of the evaluation, or how and why the prior injuries were responsible for 80% of applicant's left ankle disability. Therefore, his opinions do not comply with the requirements of the applicable case law and they do not constitute substantial evidence as to the issue of apportionment. (Acme Steel v. Workers' Comp. Appeals Bd. (Borman), supra; Escobedo v. Marshalls, supra.)