Harriett R. Martin was awarded gen*611eral compensation benefits on the referee’s determination that she had suffered a work-related disability. The Worker’s Compensation Appeal Board affirmed that determination, finding that she was "continually disabled”. That determination was not appealed and she is, therefore, entitled to general compensation benefits from her employer, Ford Motor Company, for the duration of the disability.
Since 1965 the act has provided for an annual adjustment in the maximum weekly rate of compensation to reflect changes in the average weekly wage paid employed workers. An upward adjustment in the maximum rate benefits only workers subsequently injured, except that a worker who is totally and. permanently disabled is entitled to receive, from the Second Injury Fund, differential benefits reflecting post-injury adjustments.1
Martin claims that in addition to the general compensation benefits, payable by her employer, she is entitled to differential benefits from the Second Injury Fund to reflect increases since 1966, the year of injury, in the average weekly wage paid employed workers.2 The issue is whether Martin’s disability is total and permanent entitling her to differential benefits.3
The referee also determined that Martin’s disability was total and permanent on a finding that she had lost the industrial use of both legs and *612had also lost the use of one leg and one arm. In reversing that determination the WCAB declared that the evidence of industrial loss of both legs and of one arm was "so scarce that it is utterly inadequate to support a finding of total and permanent disability”.4 The Court of Appeals affirmed, stating that "[t]here is record support” for the WCAB’s finding.5
My colleague states that the WCAB should be affirmed because Martin failed "to show that the work-related aggravation [of her pre-existing back injury] resulted in the loss of industrial use of her legs or a leg and an arm” (emphasis in original).
Neither Ford nor the Second Injury Fund contended either before the WCAB or the Court of Appeals that Martin had failed to show a causal link between her work and the loss of industrial use of legs and an arm. In the WCAB they claimed that the referee erred in finding industrial loss and in finding a "causal relationship between the employment and plaintiff’s back [general] disability”. In the Court of Appeals the contention was that there was evidence to support the WCAB’s determination that Martin had not suffered the industrial loss of legs and arm; it was not claimed *613alternatively that there was no causal relationship between her employment and the asserted industrial loss.
Ford and the Second Injury Fund contend for the first time in their briefs with this Court that Martin failed to prove both industrial loss of legs and arm and a causal connection between her employment and such asserted loss.6
We reverse the WCAB and direct reinstatement of the referee’s determination awarding differential benefits because its determination is not evidentially supported: there is substantial record evidence that Martin suffered the loss of industrial use of legs and arm, it affirmatively appears that the WCAB accepted as credible the testimony of the witnesses who presented such evidence, and there is no contrary evidence.
I
The act provides that the Second Injury Fund shall pay any totally and permanently disabled person the difference between the current schedule of benefits and any lesser amount he is receiving from his employer based on the schedule of benefits in effect at the time of his injury.7
The act defines "total and permanent disability” as including "permanent and total loss of industrial use of both legs or both hands or both arms or 1 leg and 1 arm”.8
In Burke v Ontonagon County Road Commis*614sion, 391 Mich 103; 214 NW2d 797 (1974), this Court reviewed earlier decisions and said:
"In summary, Paulson [v Muskegon Heights Tile Co, 371 Mich 312; 123 NW2d 715 (1963)] and Lockwood [v Continental Motors Corp, 27 Mich App 597; 183 NW2d 807 (1970)] lay down two tests for determining whether an employment-related injury statutorily causes the 'permanent and total loss of industrial use of both legs’:
"1. It is not necessary that both legs or either leg be injured at all.
"2. The industrial loss of use of both legs may result from 'leg-connected disabling pain * * * so severe as to make use of the legs in industry practically impossible’ even though that pain is generated from an injury elsewhere in the body (Paulson) or it may result 'when a non-leg malady is triggered by use of the legs and it is that condition which prevents use of the legs in industry’ (Lockwood).
"Miller [v Sullivan Milk Products, Inc, 385 Mich 659; 189 NW2d 304 (1971)] rules, while Paulson and Lockwood take for granted that:
"The 'leg-connected disabling pain’ or the 'non-leg malady’ must be the consequence of an employment-related injury.” Id, pp 110-111.
The Court then "amplif[ied] and consolidate^] the tests in Paulson and Lockwood, as follows”:
"There is permanent and total loss of industrial use of both legs where, inter alia,
"1. An employment-related injury in one or both legs causes pain or other condition that prevents use of both legs in industry.
"2. The use of one or both legs, whether or not injured, triggers an employment-related injury or malady in any part of the body, including one or both legs, that causes pain or other condition that prevents use of both legs in industry.” Id, p 114.
Subsequently, in Triplett v Chrysler Corp, 394 *615Mich 518, 520; 232 NW2d 168 (1975), where the worker was unable to walk any distance because of emphysema, the Court declared that it was not intended that the Burke rule be read to include "those cases in which the loss of industrial use of the legs is caused by a generally debilitating disease, which affects bodily functions in much the same way and causes a general decline in those bodily functions”.9
II
Harriett Martin worked for Ford Motor Company as a records clerk for over ten years. Her last day of work was May 31, 1966 when she was approximately 49 years old and she has not worked since that date.
Martin’s back troubles began as a child with a toboggan accident and continued with an automobile accident in 1957 or 1958. As a result of an incident at home in early 1964, she underwent surgery for a herniated disc, returning to work a few months later. Shortly thereafter she was in another automobile accident which caused her severe back pain; she returned to work in October, 1964. She experienced back pain but continued to work despite her discomfort until March, 1965 when she was admitted to a hospital. In April another back operation was performed. She returned to work in July. She said that she felt fine *616until she was assigned to filing which, because of the body movements required, caused her pain. She was given favored work but then returned to filing and again experienced severe pain in her back and leg. She was hospitalized 3-1/2 weeks for physical therapy. While at home in April, 1966 she experienced pain while planting rose bushes. She returned to work for the last time on May 9. She was unable to work more than three to five hours per day because of pain in her back and leg. Following the termination of her employment she had a painful incident while shopping. There were three more operations. She testified to burning pain in her left leg and left arm, and that she cannot walk more than a block, and can stand for only half an hour.
Four physicians testified. Martin called Drs. Frank Cullis, William C. Schaefer and Otonaz Vaitos. Ford called Dr. George J. Straschnov. All four physicians agreed that Martin was disabled. The three doctors called by Martin related her disability to her employment without hesitation.
Ford’s witness, Dr. Straschnov, acknowledged that bending would aggravate her back condition and that the extent of the aggravation would depend on the extent of the bending and related activity. He said he could not find any wasting of the legs nor evidence of muscle weakness.
Dr. Schaefer, a treating physician, described the occasions for her visits to him and the treatment but was not questioned regarding loss of industrial use.
The WCAB summarized Dr. Cullis’ testimony as follows:
"Dr. Frank Cullis testified that prior to surgery plaintiff had experienced 'radiation of pain from the back, *617down the left leg to the toes’ and that she had told him 'that she had numbness in her left leg.’ However, his diagnosis of plaintiffs condition was that she 'is suffering from the sequelae of a percutaneous cordotomy and she has what I call a post-laminectomy fusion syndrome.’ ”
The WCAB declared that the "closest any doctor came to testifying about disability in lower or upper extremity was Dr. Otonaz Vaitoz [sic] who had treated plaintiff for many years”. His opinion, quoted by the WCAB, was that "she is not able to” do "industrial work” and that she was prevented from working "because of the disability of the left hand, the left leg, and the fact that she cannot work over prolonged periods of time and I mean two or three hours”.
The WCAB continued:
"This type of medical evidence coupled with the fact that plaintiff could walk at least one block, dance, and even plant some rose bushes in her yard convince us that she did not meet her burden of proof to establish the industrial loss of use of any legs or arms.”10
*618The WCAB’s recital of Dr. Cullis’ testimony and its statement that Dr. Vaitos’ testimony was the closest any doctor came to testifying about disability in legs and arm overlooked Dr. Cullis’ testimony that "I don’t think she can use [her left arm] in the industrial world, to be employed in that world”, 'T think she has severe problems” regarding the industrial use of her left leg, "I would therefore consider that she is deficient in that regard, for industrial work, the left lower extremity”, and the following testimony:
”Q. [by Martin’s attorney]: All right. I think that the referee would be interested in your opinion as to whether or not there is a substantial loss of use — of industrial use — of these two extremities.
"A. I thought I had made that clear. I believe that to be so, yes.
"Q. Is that loss of use, in your opinion, permanent?
"A. Unfortunately, I think that it will be, yes.”
Ill
Back problems differ from emphysema or heart disease in that all functions and activities of the body are not affected "more or less in the same manner as it affects the use of the legs”. Triplett v Chrysler Corp, supra, p 522. A person with emphysema or heart disease is often without energy to function at all. A person with a bad back may be able to work in a rose garden and may have energy for many things even though he or she cannot function in industry.
*619Martin is unable to walk for more than a block. She cannot stand for more than a half hour. Her right hip hurts and she loses control if she stands too long. Her left leg burns if she is standing too long and she cannot put any weight on it. She cannot lift anything substantial with her left hand.11
It is of no importance that Martin suffered injuries as a child and as an adult which were not work-related.12 The WCAB found that she was "continually disabled due to her back condition which was aggravated by her work” (emphasis supplied).
Her condition may very well have deteriorated following the termination of her employment and her disability may have become more pronounced as sequelae of the three additional operations. These sequelae are themselves work-related because they were occasioned by an effort to relieve the disability found to have been aggravated by her work.13
If it is thought that the issue of causal relationship between the work-related disability and loss of industrial use is properly before us, it is appar*620ent that Martin’s continuing inability to use her legs and arm in any meaningful way is a consequence of her work-related back condition (general disability) and continuing deterioration of that condition which may have been aggravated by the efforts to relieve her discomfort.
The central question is whether Martin has lost the industrial use of her legs and arm. If she has, that loss is clearly connected to her general disability found by the WCAB to be work-related. The only post-employment causes that have been suggested are one incident while shopping, manifestly not the cause of her debilitated condition, and the sequelae of the operations, clearly related to the back condition found to be work-related.
There is substantial medical evidence that Harriett Martin, as a result of the employment-related aggravation of her back condition, has lost the industrial use of her legs and an arm. The WCAB quoted, with apparent approval, the testimony of both Drs. Cullis and Vaitos who alone testified on the central issue of loss of industrial use. It appears therefore that their testimony was deemed credible. There is no evidence tending to show that Martin has the industrial use of her legs and arm. The evidence that sometime before her employment terminated she went dancing and planted some rose bushes does not indicate that after the three post-employment operations she is able to perform employment-related tasks on a regular work schedule.14
As set forth in Burke v Ontonagon County Road Commission, supra, p 110, it is not necessary that either leg "be injured at all”, and therefore it is of *621no consequence that Dr. Straschnov could not find any wasting in the legs nor evidence of muscle weakness.
It is undeniable on this record that when Harriett Martin uses one or both of her legs for more than a brief span of time she suffers severe pain that "prevents use of both legs in industry”. Id, p 114. In these circumstances the WCAB is not at liberty, through selective fact-finding, to substitute its judgment of what constitutes sound public policy regarding payment of differential benefits for loss of industrial use of limbs for the legislatively ordained policy as elucidated in the decisions of this Court. See Gacesa v Consumers Power Co, 220 Mich 338; 190 NW 279; 24 ALR 675 (1922), holding that the question becomes one of law for the Court to decide where there is no conflict in the testimony and only one inference can legitimately be drawn from it.15
We reverse and remand to the Worker’s Compensation Appeal Board for entry of an order affirming the referee.
Kavanagh, C. J., and Williams and Blair Moody, Jr., JJ., concurred with Levin, J.1965 PA 44, § 9; 1948 CL 412.9; MSA 17.159; now MCLA 418.355; MSA 17.237(355) (adjustments in the maximum weekly rate of compensation), and MCLA 418.521(2); MSA 17.237(521X2) (payments by the Second Injury Fund).
The referee ordered differential benefits of $5 per week for 1969, $11 per week for 1970 and $15 per week for 1971, subject to additional adjustments in later years as provided for in the act.
Ford did not file a brief in the Court of Appeals or an answer in response to Martin’s application for leave to appeal to this Court. It signed, together with the Second Injury Fund, a brief in this Court.
The WCAB also declared, similarly:
"[T]he record does not support a finding of total and permanent disability within the meaning of the act.
"Plaintiff just has not met her burden of proving that the use of her lower extremities triggers 'pain or other conditions that prevents use of both legs in industry.’ ”
The phrase quoted by the WCAB is from Burke v Ontonagon County Road Commission, 391 Mich 103, 114; 214 NW2d 797 (1974).
Judge T. M. Burns dissented in the Court of Appeals and said:
"Not only does the record indicate that there was evidence to support a finding of total and permanent disability, but as the board’s minority opinion points out, the unrebutted proofs show that plaintiff had in fact suffered the industrial loss of the lower limbs and the left arm, as found by the referee.”
In this connection we note that our grant of leave was limited to the issue posited in Martin’s application for leave to appeal of whether all the evidence demonstrated that Martin had suffered loss of industrial use so that the WCAB should have awarded differential benefits.
See fn 1, supra.
1948 CL 412.10; MSA 17.160; now MCLA 418.361; MSA 17.237(361).
The Court elaborated:
"We hold that there is not permanent and total loss of industrial use of both legs where the use of one or both legs, whether or not injured, triggers an employment-related malady, such as one of the heart, lung, or kidneys, which by itself or in connection with any physical exertion reacts to affect all functions and activities of the body more or less in the same manner as it affects the use of the legs, even though it does prevent use of both legs in industry.” Triplett v Chrysler Corp, 394 Mich 518, 522; 232 NW2d 168 (1975).
Earlier in its opinion the WCAB declared:
"However, even-though we find that plaintiff is continually disabled due to her back condition which was aggravated by her work, we must agree with defendant that the referee erred in his finding of industrial loss of use of both legs and one arm.
"The overwhelming weight of the medical proofs points to back disability and any reference to industrial loss of use of lower or upper extremities is so scarce that it is utterly inadequate to support a finding of total and permanent disability.”
The WCAB concluded:
"We find that plaintiff continues to be a disabled person due to her back condition and is entitled to compensation for the duration of her disability. However, the record does not support a finding of total and permanent disability within the meaning of the act.
"In our opinion, though totally disabled, she does not qualify for a designation of a totally and permanently disabled person either within the meaning of the act or the tests enumerated by the Supreme Court in Burke v Ontonagon County Road Commission, 391 Mich (1974). Plaintiff just has not met her burden of proving that the *618use of her lower extremities triggers 'pain or other conditions that prevents use of both legs in industry.’
"Accordingly, that part of the referee’s decision finding industrial loss of use of plaintiff’s lower extremities and left arm shall be reversed, relieving the Second Injury Fund of any liability for differential benefits. In all other respects, the referee’s decision is affirmed.”
Dr. Cullis said her grip in her left hand is 12 pounds as compared with her right hand which is 55 pounds.
See Riddle v Broad Crane Engineering Co, 53 Mich App 257; 218 NW2d 845 (1974); Larson, Workmen’s Compensation Law, § 12.20, pp 3-231-3-265.
See Oleszek v Ford Motor Co, 217 Mich 318; 186 NW 719 (1922); Larson, supra, § 13.21, pp 3-310-3-319.
This principle is also recognized in the common law:
"A similar group of cases hold the defendant liable for the results of medical treatment of the injured victim. Even where such treatment is itself negligent, because of lack of proper skill or care, recovery for its consequences is permitted. It would be an undue compliment to the medical profession to say that bad surgery is no part of the risk of a broken leg. So long as the plaintiff himself has exercised reasonable care in his selection of a physician, the defendant will be liable for all ordinary forms of professional negligence.” Prosser, Torts (4th ed), § 44, pp 278-279.
See Lockwood v Continental Motors Corp, 27 Mich App 597, 607; 183 NW2d 807 (1970), where the worker could walk or drive an automobile but the Court nevertheless held that he could obtain benefits for loss of industrial use of his legs.
"We do not ordinarily consider the rulings of the department on the admissibility of testimony where there is competent testimony to sustain its findings. We should not here if there was any competent testimony to support the findings. But the rejected testimony here is not only undisputed by any testimony in the record or by any legitimate inference which might be drawn from the testimony in the record but it is corroborated by all the testimony in the record bearing on the subject. Where undisputed controlling testimony is improperly rejected by the department of labor and industry and the case is brought here on certiorari our duty is to consider such testimony and apply the proper rules of law to the undisputed facts. We do not weigh and measure conflicting testimony but where there is no conflict in the testimony, where it is all one way, where there is nothing in any way inconsistent in it, where but one inference can legitimately be drawn from it, the question then becomes one of law which upon certiorari we are bound to decide.” Gacesa v Consumers Power Co, 220 Mich 338, 341; 190 NW 279; 24 ALR 675 (1922).