Plaintiff appeals from a Workmen’s Compensation Appeal Board opinion and order of April 20, 1978, which affirmed an administrative law judge’s dismissal of plaintiff’s second petition for a determination of total and permanent disability on the basis of res judicata. We granted leave to appeal on August 25, 1978.
Plaintiff sustained a hip injury on March 17, 1959, while he was working for Asplundh Tree Expert Co. Aetna Casualty and Surety, Asplundh’s worker’s compensation insurance carrier, voluntarily paid compensation for the statutory maximum of 500 weeks. The 500-week period expired on January 9, 1969.
In February of 1970, plaintiff’s wife filed a petition for hearing on plaintiff’s behalf. The petition alleged the following disabilities:
*411"4th Vertibrae damaged beyond repair. Arms Back neck legs shows marked weakness. Bloodclot on spinal cord; nerve root compression; imbecility or feeble minded; Drug addiction.”
A hearing on this petition was held on August 4 and 5, 1971. Plaintiff acted without legal counsel and benefits were denied because:
"* * * plaintiff has failed to sustain the burden of proof to show that he is totally and permanently disabled within the meaning of that term as used in the Workmen’s Compensation Act.”
On January 3, 1972, plaintiff, again acting through his wife and without the benefit of legal counsel, appealed this hearing referee’s decision to the Workmen’s Compensation Appeal Board. The board dismissed plaintiff’s appeal on March 30, 1972, for failure to provide a transcript of the proceedings before the hearing referee.
On January 28, 1976, plaintiff, through legal counsel, filed a new petition for hearing. This petition alleged disability in part as follows:
"* * * loss of industrial use of both legs; traumatic shock with onset of psychogenic dysfunction; total permanent disability”.
This matter was set for a hearing before Administrative Law Judge Frank Condino on February 14, 1977. At this hearing, defendant Aetna Casualty and Surety moved to dismiss plaintiff’s claim on the basis of res judicata. The Second Injury Fund joined in this motion. By a decision mailed February 17, 1977, Judge Condino granted defendant’s motion to dismiss, indicating in pertinent part:
*412"I am bound to administer the law, in particular, the Workmen’s Compensation Act. So, I will grant Defendant’s Motion to Dismiss, based on the matter having been fully tried and the matter being Res Judicata [sic]”
Plaintiff appealed this dismissal to the Workmen’s Compensation Appeal Board on February 17, 1977. The board, by a majority vote of 3 to 2, affirmed the dismissal on April 20, 1978, stating in part:
"Plaintiff appeals the dismissal of his petition seeking total and permanent disability benefits. The subject matter of his petition having already been litigated to a conclusion and final order, the decision (dismissal) is affirmed.”
The appeal board majority rejected plaintiff’s loss of industrial use of both legs claim after determining that the 1971 hearing decided that issue and a subsequent finding of worsened condition would not avoid the time limit established by MCL 418.361(2)(g); MSA 17.237(361)(2)(g).
The majority rejected plaintiff’s psychogenic dysfunction claim after determining that the language used did not allege entitlement to total and permanent disability on the basis of incurable insanity or imbecility under MCL 418.361(2)(f); MSA 17.237(3<31)(2)(f).
We are faced with two issues on appeal. First, whether the appeal board erred in affirming the dismissal of plaintiff’s claim for total and permanent disability based on loss of industrial use of both legs. Second, whether the appeal board erred in affirming the dismissal of plaintiff’s psychogenic dysfunction claim.
We note at the outset that plaintiff’s psycho*413genic dysfunction claim, while not couched in the words of the statute, should have been enough to alert all those involved that the plaintiff was claiming total and permanent disability due to the psychological condition of either incurable insanity or imbecility. Consequently, the appeal board’s reason for upholding the dismissal of this claim must be rejected.
At this point, however, we become stymied. In general, res judicata applies not only to issues which were determined on the merits but also to matters which the parties had the opportunity to present for adjudication on the merits. Stokes v Lakey Foundry Corp, 20 Mich App 217, 219; 173 NW2d 832 (1969), and cases cited therein. But in worker’s compensation cases, res judicata applies only where the precise issue of fact or law under consideration in one case was at issue and decided in prior proceedings. White v Michigan Consolidated Gas Co, 352 Mich 201, 211; 89 NW2d 439 (1958), Stokes, supra, and see Hlady v Wolverine Bolt Co, 393 Mich 368, 376; 224 NW2d 856 (1975).
Further, when the appeal board reviews the decision of an administrative law judge, that review is de novo. Fawley v Doehler-Jarvis Division of National Lead Co, 342 Mich 100; 68 NW2d 768 (1955). Accordingly, a determination that a given case is barred by res judicata must also be reviewed de novo. The board must determine what the first hearing actually resolved and then compare those determinations with the plaintiffs claims in the subsequent case.
The problem here lies in determining just what was at issue and decided in the 1971 hearing. The 1970 petition for benefits was inartfully drafted and alleged a mishmash of disabilities. The hearing referee denied benefits for the general reason *414that plaintiff failed to show that he was "totally and permanently disabled within the meaning of that term as used in the Workmen’s Compensation Act”. And while plaintiff appealed the referee’s findings, the appeal was dismissed because the plaintiff failed to provide the appeal board with a transcript of the proceedings before the hearing referee. The appeal board apparently has still not seen the transcript of the 1971 hearing. We echo the words of appeal board member Marshall, who dissented from the majority opinion of the appeal board in this case:
"In a fundamental sense we just do not really know (at least without the record and transcript of the prior proceedings) exactly what has been adjudicated and determined; that is, precisely what crucial factual issues were actually litigated and determined, and, therefore what legal issues were necessarily resolved.” (Emphasis in original.)
Under these circumstances, the application of res judicata principles to the present case was premature at best. See generally, Morgan v Freedman Artcraft, 401 Mich 54; 257 NW2d 85 (1977), and Sanders v General Motors Corp, 80 Mich App 190; 263 NW2d 329 (1977), lv gtd 402 Mich 950i (1978). Accordingly, the matter must be remanded to the Workmen’s Compensation Appeal Board for a determination of what was at issue and decided in the 1971 hearing. After making that determination the board should reexamine this case in light of the above mentioned cases. If there is not enough information available to determine what was at issue and actually decided in the 1971 hearing, res judicata does not bar plaintiffs claims and he is entitled to a hearing.
Reversed in part and remanded for proceedings *415consistent with this opinion. We do not retain jurisdiction. No costs, neither party having prevailed in full.
Danhof, C.J., concurred.