In order to make out her case, the plaintiff was required to offer competent evidence sufficient to permit the jury to make legitimate findings: (1) The defendants negligently failed properly to install and to maintain the small or auxiliary rig attached to plaintiff’s arm; (2) the failure resulted in the rig’s collapse; (3) the collapse caused a refracture of the bone in the arm; (4) the plaintiff suffered damages as a result of the negligence. A failure to establish any link in the above chain would break continuity and would be sufficient legal ground to defeat plaintiff’s claim and to require the court to sustain the motion to dismiss.
All the evidence came from the witnesses called by the plaintiff. Dr. Wentz, a defendant, testified describing the diagnosis, operation, treatment, and the installation and purpose of two rigs designed to aid in restoring and keeping proper bone alignment. He identified x-ray photographs taken four days before and three days after the small rig collapsed. These photographs showed there was no change in the bone position at the point of the break between the dates October 29th and November 5th. He testified unequivocally that at the time he performed the operation on the latter date, he found the broken ends of the bone, though out of exact alignment, had healed to the extent that he was required to use heavy instruments, including a hammer, to separate the joinder in order that he might re*300position the ends of the bone, restoring proper alignment. He testified that in the diagnosis and treatment he followed approved medical and surgical procedures.
There is a total absence of expert or other testimony that the procedure followed in attaching the light rig to the patient’s arm was other than in strict conformity with approved medical and surgical practice. There was evidence the adhesive tape which held the light rig, after several days, began to come loose from the skin. When this fact was called to the attention of the nurse, she applied additional tape. Dr. Wentz checked and rewound the elastic bandage after the repairs were made by the nurse. Thereafter, the weight, though light, caused the bandage to break loose from the arm resulting in the collapse. A showing the rig collapsed is not enough to show negligence. Something more must be shown before negligence may be inferred. Boyd v. Kistler, 270 N.C. 744, 155 S.E. 2d 208; Galloway v. Lawrence, 266 N.C. 245, 145 S.E. 2d 861; Hunt v. Bradshaw, 242 N.C. 517, 88 S.E. 2d 762; Hawkins v. McCain, 289 N.C. 160, 79 S.E. 2d 493.
Plaintiff argues she has offered sufficient evidence to justify the jury in finding the collapse of the rig caused a refracture, notwithstanding the testimony of Dr. Wentz to the contrary. In support of her contention, her counsel produced and Dr. Wentz identified a letter he wrote on July 22, 1970. The letter stated: “I .. . was, of course, surprised to see that a complete separation of this healing fracture had occurred, making it mandatory that some surgical treatment be instituted. . . . In summary, I think that we cannot be certain as to when fracture position was lost. It could have occurred when the skin traction slipped off . . . . ” The letter was introduced as plaintiff’s Exhibit No. 27.
On cross-examination, Dr. Wentz by way of explanation testified : “The letter has some erroneous portions. This letter was dictated a year after surgery and I had the impression that this fracture had slipped or rotated when I saw the x-ray on November 3, 1969. At that time of the operation, I found that the fracture had not slipped. It was indeed quite firmly attached in a side-to-side position, and the fracture had to be disrupted using a sharp, strong instrument, and this time including a hammer .... It had tó be disrupted to relocate the fractured ends, and then put them in a better position, using a Rush pin. . . . The terms that I used in this letter, including the term ‘complete *301separation of this healing fracture,’ I will repudiate at this time. . . . Yes, I would also repudiate the statement Tn summary, I think that we cannot be certain as to when fracture position was lost.’ ”
In a further effort to show the collapse caused a refracture the plaintiff called Dr. Dorman, also a qualified expert in orthopedics. In answer to a hypothetical question, Dr. Dorman stated that the collapse of the rig could, or might have caused a refrac-ture. However, when the extent of the healing process disclosed by the x-rays and the operation was included in the question, Dr. Dorman said that his opinion would be the collapse did not cause a refracture.
[1] The plaintiff was without expert or other testimony showing negligence in installing or maintaining the light rig. All the testimony was to the contrary. All the damages and all liability alleged in the complaint are grounded on negligence in the installation and maintenance of the auxiliary rig resulting in a refracture. “A party is bound by his pleadings and, unless withdrawn, amended, or otherwise altered, the allegations contained in all pleadings ordinarily are conclusive as against the pleader.” Davis v. Rigsby, 261 N.C. 684, 136 S.E. 2d 33. Rule 15(b), Rules of Civil Procedure is inapplicable in this case. Here the pleadings specifically raise the issues. Roberts v. Memorial Park, 281 N.C. 48, 187 S.E. 2d 721.
[2] Prior to the adoption of the new Rules of Civil Procedure, the plaintiff would have been precluded from offering Exhibit No. 27 for the purpose of impeaching the testimony of her witness Dr. Wentz. The old rule is stated in 7 Strong N. C. Index 2d, Witnesses, § 4, page 694: “Since a party calling and examining a witness represents him to be worthy of belief, he may not impeach the credibility of such witness, even though the witness is the adverse party.” Powell v. Cross, 263 N.C. 764, 140 S.E. 2d 393. However, the new Rules of Civil Procedure have made significant changes. Rule No. 43(b) provides: “Examination of hostile witnesses and adverse parties. — A party may interrogate any unwilling or hostile witness by leading questions and may contradict and impeach him in all respects as if he had been called by the adverse party.”
Under the new rule, Dr. Wentz, though called by the plaintiff as her witness, nevertheless may be impeached by his letter. Apparently the letter could be treated as an admission against *302interest. Board of Education v. Lamm, 276 N.C. 487, 173 S.E. 2d 281.
Even if it be found the letter (Exhibit No. 27) is an admission against interest, nevertheless the letter in no wise suggests there was negligence in the use or maintenance of the light rig, causing its collapse. A showing of negligence in such matters was vital to the plaintiff’s case. By failure to show the negligence alleged in the complaint, the plaintiff has failed to carry the burden of proof.
The judgment in the superior court and the decision of the Court of Appeals are supported by the record and are in accordance with our case law. This conclusion is sustained by the following and many other authoritative decisions of this Court. In the light of the pleadings, the evidence, and the principles of law hereinafter discussed, no issue of fact triable by a jury was presented. Hence, Judge Peel was required to grant defendants’ motion to dismiss. Cutts v. Casey, 278 N.C. 390, 180 S.E. 2d 297; Rule 50(a), Rules of Civil Procedure, G.S. 1A-1.
[3] In this, as in all cases involving negligent failure of the surgeon or physician to render professional treatment for diseases or injuries, the plaintiff cannot rely on common knowledge or lay testimony to make out a case for the jury. In cases of diseases or injuries “with respect to which a layman can have no knowledge at all, the court and the jury must be dependent on expert evidence. There can be no other guide, and, where want of skill or attention is not thus shown by expert evidence applied to the facts, there is no evidence of. it proper to be submitted to the jury.” Smith v. Wharton, 199 N.C. 246, 154 S.E. 12.
“Thus, it is not enough to absolve the physician from liability that he possesses the required professional knowledge and skill. He must exercise reasonable diligence in the application of that knowledge and skill to the particular patient’s case and give to the patient such attention as the case requires from time to time. Galloway v. Lawrence, supra. On the other hand, a qualified physician, who forms his judgment after a careful and proper examination or investigation of the particular patient’s condition, is not an insurer of his diagnosis or of the success of his treatment and is not liable for an honest error of judgment.” Dickens v. Everhart, 284 N.C. 95, 199 S.E. 2d 440.
*303“In order to warrant a jury in finding liability on the part of the surgeon, negligence must be established by the evidence. In order to escape nonsuit, evidence sufficient to permit a legitimate inference of facts constituting negligence must be offered. Nash v. Royster, 189 N.C. 408, 127 S.E. 356. Ordinarily, the Court must determine as a matter of law whether the evidence in its light most favorable to the plaintiff is sufficient to permit legitimate inference of the facts necessary to be proved in order to establish actionable negligence. Construction Co. v. Board of Education, 262 N.C. 295, 136 S.E. 2d 635. ‘It is the duty of the court to allow the motion (nonsuit) in either of two events: First, when all the evidence fails to establish a right of action on the part of the plaintiff; second, when it affirmatively appears from the evidence as a matter of law that the plaintiff is not entitled to recover.’ ” Lentz v. Thompson, 269 N.C. 188, 152 S.E. 2d 107.
“Proof of what is in accord with approved surgical procedure and what constitutes the standard of care required of the surgeon in performing an operation, like the advisability itself, are matters not within the knowledge of lay witnesses but must be established by the testimony of qualified experts.” Hunt v. Bradshaw, supra.
When tested by the foregoing rules, the evidence of actionable negligence on the part of either of the physicians or the hospital was insufficient to be submitted to the jury. This record leaves the impression that a competent and skillful orthopedic surgeon gave expert treatment to a patient, age thirteen, for an extremely serious injury. The lower end of the broken bone in her upper right arm was jammed into her shoulder. The ends of the broken bone overlapped by as much as one inch. Dr. Wentz concluded that on account of her tender age, a cutting operation to realign the broken ends so soon after the injury might so disturb and disrupt the tendons, nerves, and blood vessels that continued growth of the arm would be endangered leaving it shorter and smaller than the left. Hence, he decided to apply traction to the lower arm and by the pulling force of the weight, gradually extend the lower arm until the broken bone was properly joined and realigned. However, x-rays taken after the rig was removed, disclosed the misalignment necessitating the operation. In the meantime, however, the ligaments, tendons, blood vessels, etc. had approached their normal condition. The opera*304tion turned out to be successful, leaving the arm as good as new except for the scar.
Judge Peel was correct in entering judgment dismissing the action. The decision of the Court of Appeals was correct in affirming the judgment. That decision is now
Affirmed.
Chief Justice Bobbitt not sitting.