ADJ7155088 · October 5, 2026

The Appeals Board found that the WCJ and AMEs failed to adequately determine whether there were one or two cumulative trauma periods and the exact date of injury, requiring further development of the record to clarify these issues.

From the decision · page 13injurious or merely exacerbated the pre-2006 pathology, any determination of the number of cumulative trauma periods and the identity of the liable carrier under section 5500.5(a) would rest on surmise rather than substantial evidence. On return, we recommend that the WCJ develop the record on the issues identified above. This may include: (1) supplemental reports or deposition testimony from the AMEs regarding separate cumulative trauma periods and the section 5412 knowledge component; (2) evidence clarifying applicant’s post-December 11, 2006 duties and their causal link to any disability; and (3) any other evidence the WCJ deems necessary. Upon the record’s completion, the WCJ shall issue a new decision consistent with the authorities discussed herein. With respect to applicant’s claim for increased permanent disability pursuant to section 4658(d), we make no findings at this time. However, since we are returning the matter for further development of the record, if further evidence is needed to determine this issue, the parties will now have the opportunity to submit it. Accordingly, we rescind the F&A and return the matter to the trial level for further proceedings consistent with this opinion.

No findings were made on the applicability of section 4658(d) permanent disability increase; the issue was deferred for further evidence and determination on remand.

From the decision · page 13injurious or merely exacerbated the pre-2006 pathology, any determination of the number of cumulative trauma periods and the identity of the liable carrier under section 5500.5(a) would rest on surmise rather than substantial evidence. On return, we recommend that the WCJ develop the record on the issues identified above. This may include: (1) supplemental reports or deposition testimony from the AMEs regarding separate cumulative trauma periods and the section 5412 knowledge component; (2) evidence clarifying applicant’s post-December 11, 2006 duties and their causal link to any disability; and (3) any other evidence the WCJ deems necessary. Upon the record’s completion, the WCJ shall issue a new decision consistent with the authorities discussed herein. With respect to applicant’s claim for increased permanent disability pursuant to section 4658(d), we make no findings at this time. However, since we are returning the matter for further development of the record, if further evidence is needed to determine this issue, the parties will now have the opportunity to submit it. Accordingly, we rescind the F&A and return the matter to the trial level for further proceedings consistent with this opinion.

Applicant worked as a tower crane operator with cumulative trauma exposure through August 28, 2009, and had a prior temporary disability period in 2006.

Favours neutral

This fact was central to the dispute over the number of cumulative trauma periods and the date of injury, affecting liability and benefits.

From the decision · page 4Conrad, after evaluating applicant in the field of orthopedics, took a history that he began experiencing insidious low back and left leg pain in approximately 2006 when modified occupational safety standards compelled him, a six-foot- seven-inch individual, to ascend enclosed crane ladders sideways. (Joint Ex. 101, pp. 2-3, 11.) Despite developing an increasingly ataxic gait that necessitated the use of one walking stick in 2007 and two walking sticks by 2009, applicant continued working until his final day of work on August 28, 2009, and his retirement in October 2009. (Id. at pp. 2-4, 13.) AME Dr.

Favours Applicant prevailed

This error required recalculation of temporary disability payments under Labor Code section 4661.5.

The medical opinions of AME Dr. Conrad were found speculative and incomplete for failing to consider post-2006 work environment and flare-up as a new source of trauma.

Favours Applicant prevailed

This undermined the WCJ's reliance on Dr. Conrad's opinion regarding cumulative trauma periods, necessitating further record development.

From the decision · page 11stating there was “no evidence to support two periods of cumulative trauma.” This analysis ignores the mandate of Coltharp, which requires an assessment of whether an intervening period of disability and a subsequent return to work signify a separate and distinct injurious period. Furthermore, AME Dr. Conrad failed to evaluate the post-December 2006 work environment, nor does he explain why the intervening disability and return to full duty did not break the chain of causation. He neglected to consider whether applicant’s post-December 2006 flare-up constituted a new source of repetitive microtrauma. Consequently, AME Dr. AME Dr. Conrad’s opinion rests upon an incomplete history and remains speculative under the standards set forth in Escobedo. AME Dr. Weiss, in contrast, documented two separate claim filings, a two-month period of temporary disability resolving sufficiently for return to full duty, approximately two years of subsequent regular work, and then a flare of symptoms linked to climbing a 300-foot caged enclosed ladder. Her neurologic opinion attributes the later gait dysfunction and polyneuropathy to a combination of lumbar nerve-root compromise and cephalad spinal pathology that progressed after the return to work. These observations are consistent with the possibility of a second period of injurious exposure, yet AME Dr.

Documented two separate claim filings and a two-month temporary disability period with return to full duty, followed by a flare linked to climbing a 300-foot ladder; attributed later gait dysfunction and polyneuropathy to lumbar nerve-root compromise and cephalad spinal pathology; did not opine on whether post-2006 work caused a distinct cumulative injury.

Provided a more complete history supporting possibility of a second injurious exposure period; not asked to opine on distinct cumulative injury.

From the decision · page 11stating there was “no evidence to support two periods of cumulative trauma.” This analysis ignores the mandate of Coltharp, which requires an assessment of whether an intervening period of disability and a subsequent return to work signify a separate and distinct injurious period. Furthermore, AME Dr. Conrad failed to evaluate the post-December 2006 work environment, nor does he explain why the intervening disability and return to full duty did not break the chain of causation. He neglected to consider whether applicant’s post-December 2006 flare-up constituted a new source of repetitive microtrauma. Consequently, AME Dr. AME Dr. Conrad’s opinion rests upon an incomplete history and remains speculative under the standards set forth in Escobedo. AME Dr. Weiss, in contrast, documented two separate claim filings, a two-month period of temporary disability resolving sufficiently for return to full duty, approximately two years of subsequent regular work, and then a flare of symptoms linked to climbing a 300-foot caged enclosed ladder. Her neurologic opinion attributes the later gait dysfunction and polyneuropathy to a combination of lumbar nerve-root compromise and cephalad spinal pathology that progressed after the return to work. These observations are consistent with the possibility of a second period of injurious exposure, yet AME Dr.

Diagnosed lumbar degenerative disc disease with left S1 radiculopathy, bilateral degenerative osteoarthritis of the hips, and polysensory neuropathy of the lower extremities; opined cumulative trauma through August 28, 2009 caused injuries; rejected subdivision of causation into two periods of cumulative trauma as speculative.

Opinion rests on incomplete history and is speculative as it ignores intervening disability and return to work; failed to evaluate post-December 2006 work environment and flare-up as a new source of trauma.

From the decision · page 11stating there was “no evidence to support two periods of cumulative trauma.” This analysis ignores the mandate of Coltharp, which requires an assessment of whether an intervening period of disability and a subsequent return to work signify a separate and distinct injurious period. Furthermore, AME Dr. Conrad failed to evaluate the post-December 2006 work environment, nor does he explain why the intervening disability and return to full duty did not break the chain of causation. He neglected to consider whether applicant’s post-December 2006 flare-up constituted a new source of repetitive microtrauma. Consequently, AME Dr. AME Dr. Conrad’s opinion rests upon an incomplete history and remains speculative under the standards set forth in Escobedo. AME Dr. Weiss, in contrast, documented two separate claim filings, a two-month period of temporary disability resolving sufficiently for return to full duty, approximately two years of subsequent regular work, and then a flare of symptoms linked to climbing a 300-foot caged enclosed ladder. Her neurologic opinion attributes the later gait dysfunction and polyneuropathy to a combination of lumbar nerve-root compromise and cephalad spinal pathology that progressed after the return to work. These observations are consistent with the possibility of a second period of injurious exposure, yet AME Dr.

Labor Code section 4661.5

Temporary disability payments more than two years from the date of injury are payable at the statutory amount prevailing when the payment is made, pursuant to Labor Code section 4661.5.

The WCJ erred in awarding temporary disability at the 2009 maximum rate rather than the higher rate justified by stipulated earnings under section 4661.5, requiring recalculation on remand.

Gravlin v. City of Vista (2017)

The Appeals Board found the WCJ and AMEs failed to adequately determine whether there were one or two cumulative trauma periods, requiring further development of the record.

Applicant's testimony and medical history documenting two claim filings, a period of temporary disability, return to full duty, and a flare-up linked to increased physical demands in 2009.

From the decision · page 11stating there was “no evidence to support two periods of cumulative trauma.” This analysis ignores the mandate of Coltharp, which requires an assessment of whether an intervening period of disability and a subsequent return to work signify a separate and distinct injurious period. Furthermore, AME Dr. Conrad failed to evaluate the post-December 2006 work environment, nor does he explain why the intervening disability and return to full duty did not break the chain of causation. He neglected to consider whether applicant’s post-December 2006 flare-up constituted a new source of repetitive microtrauma. Consequently, AME Dr. AME Dr. Conrad’s opinion rests upon an incomplete history and remains speculative under the standards set forth in Escobedo. AME Dr. Weiss, in contrast, documented two separate claim filings, a two-month period of temporary disability resolving sufficiently for return to full duty, approximately two years of subsequent regular work, and then a flare of symptoms linked to climbing a 300-foot caged enclosed ladder. Her neurologic opinion attributes the later gait dysfunction and polyneuropathy to a combination of lumbar nerve-root compromise and cephalad spinal pathology that progressed after the return to work. These observations are consistent with the possibility of a second period of injurious exposure, yet AME Dr.