Unilateral Operations Research Articles

An Evaluation of a Method of Trochanteric Fixation Using Three Wires in the Charnley Low Friction Arthroplasty

The crossed wire technique of trochanteric reattachment, with ambulation from the second day after the arthroplasty, resulted in 2.3% of complete detachments, and 2.7% of fibrous union at one year (total failure rate of 5%). Of 75 trochanters which had a fibrous union at 3 months, 2 later became completely detached, 27 remained as a fibrous union and 46 progressed to complete or partial bony union by one year. The incidence of defective trochanteric union was 2.3 times more frequent in arthroplasties performed by residents in training than it was in those performed by senior staff, (10.8% and 4.6% respectively at 3 months and 5.6% and 2.4% respectively at 12 months). The incidence of defective trochanteric union in bilateral arthroplasties was double the rate in unilateral operations, (14% and 7% respectively). Eighty-six and one half per cent of the arthroplasties which developed defective union of the trochanter showed follow-up radiographic evidence of defective fixation, though 13.5% were apparently satisfactory on discharge. Roughly 79% (79.2%) of the cases which developed defective union of the trochanter developed broken wires within one year of the arthroplasty. Relief from pain by total joint arthroplasty was not significantly influenced by defective trochanteric union (mean postoperative grade for pain 5.8).

The differential effects of additional cortical lesions in rats with single- or multiple-stage lesions of the visual cortex

Male albino rats relearned a black-white discrimination for food after posterior neocortex was bilaterally removed in a single operation (“single stage”) or in two unilateral operations (“multiple stage”). Single-stage animals showed no savings in relearning (relearning errors = learning errors). Multiple-stage animals showed positive savings (relearning errors < learning errors). To assess cortical reorganization, the rats were given additional lesions and again retrained. Cortex either contiguous or noncontiguous with the posterior lesion was removed bilaterally. Contiguous and noncontiguous lesions produced different effects only among animals with prior multiple-stage posterior lesions. Rats with single-stage posterior lesions and contiguous or noncontiguous lesions showed positive savings and did not differ from each other or from rats with multiple-stage posterior and noncontiguous lesions. Rats with multiple-stage posterior and contiguous lesions made more errors and showed negative savings. The role of contiguous cortex in the serial lesion effect was also tested with two additional groups. Rats given noncontiguous cortex lesions prior to multiple-stage posterior lesions showed positive savings in retraining. Rats given contiguous cortex lesions prior to multiple-stage posterior lesions showed negative savings.

Further evaluation of a sensitive method for detecting experimental brain lesions.

Small, unilateral cortical lesions were placed in either medial-anterior, lateral-anterior, or posterior cortex of 20 male, Sprague-Dawley, albino rats. In addition, unilateral sham operations were performed on 8 rats from the same stock. All subjects had been trained prior to surgery with diametrically opposed visual habits mediated by opposite cerebral hemispheres. The opposing habits were, insofar as possible, evenly matched prior to surgery. After surgery, lesioned hemispheres, regardless of locus of lesion, were slower in acquiring the habit they mediated, than were unlesioned hemispheres. Further, unlesioned hemispheres dominated in test trials in which subjects chose one of the two cue doors with both eyes open. These findings confirm that the "interocularly conflicting discrimination" baseline detects a role of extrastriate cortex in mediation of pattern discrimination habits. They further indicated that losses occur without regard to the various locations of lesion employed.

Vaso-Epididymal Anastomosis

Our experiences with 343 vaso-epididymal anastomosis operations carried out for the relief of obstructive azoospermia in the past 20 years were reported. The etiologic factors in obstructive azoospermia were discussed. Smallpox was the single most common factor responsible for the obstructive lesion in our series. Obstructive azoospermia due to congenital anomalies was very infrequent. The pathologic physiology of obstructive azoospermia was reviewed. In 37 patients vaso-epididymostomy could not be carried out because of some genital pathology or congenital abnormality. Vaso-epididymal anastomosis was performed in the remaining 281 patients. The operation was succesful in 137 patients (48.75%), and pregnancies occurred in 40 instances (14.23%). However, even after successful operations, the postoperative sperm counts were above 20 million/ml in only 56 patients (19.93%). Persistent necrospermia resistant to treatment was noted in 48 patients (35.04%). In 71 patients (51.83%), spermatozoa appeared in the semen within the first 3 months after operation, but, in 17 patients (12.41%), the appearance of spermatozoa in the semen was delayed for 1 year or more. Twenty patients (7.11%) again became azoospermic after a variable length of time. In this series, bilateral operations were performed on 185 patients and unilateral operations were performed on 96 patients. Our results indicated beyond doubt that bilateral operation is the method of choice. In addition, an analysis of our data showed that operations performed with an internal nylon splint yield more satisfactory results.

The influence of unilateral operations with reference to the soft tissue only, on the growth of the skull

Summary In animal experiments on young inbred rats, repairs were made in the vestibulum of the upper jaw as used in the classic operations of cleft lips. We found a deviation of the anterior nasal spine from the median line of the skull to the operated side which we consider to be due to the cicatricial tension.

The influence of unilateral operations, with reference to the soft tissue only, on the growth of the skull: Experimental studies on rats

In animal experiments on young inbred rats, repairs were made in the vestibulum of the upper jaw as used in the classic operations of cleft lips. We found a deviation of the anterior nasal spine from the median line of the skull to the operated side which we consider to be due to the cicatricial tension.

Psychological aspects of the stereotactic treatment of Parkinsonism.

The beneficial clinical effects of stereotactic lesions in the ventrolateral nucleus of the thalamus in the treatment of Parkinsonism are well established. Studies of the cognitive and personality changes, however, have given contradictory results. This may be due to the great variety of tests used, to lack of control groups and to the fact that some investigators have studied only unilateral operations, whereas others have included some patients operated on bilaterally. Changes, presumably permanent, have been reported in intelligence (Jurko and Andy, 1961; Lenshoek and Manem, 1960; Niehbuhr, 1962; Jurko and Andy, 1964); concept formation (Jurko and Andy, 1961); extraversion (Fortin, 1960; Jurko and Andy, 1961); and anxiety (Niehbuhr, 1962). Transient changes have been reported in intelligence (Riklan, 1961; Levita et al., 1964); human figure drawing (Riklan et al., 1962); integrity of personality (Fortin et al., 1961; Fortin, 1960; Riklan, 1961); and somatosensory status (Proctor et al., 1963). In other studies no change was found following the operation (Bravo and Cooper, 1959; Gillingham et al., 1960; Gillingham et al., 1964; Levita and Riklan, 1965; Muller and Yasargil, 1959; Riklan, 1962).

Combined Medical and Surgical Therapy for Complicated Cases of Peripheral Uveitis

Trapdoor diathermy beneath the exudative mounds of peripheral uveitis reduced the inflammation. Five eyes were operated on because of secondary glaucoma and were controlled by diathermy and medical therapy. One eye with detachment was reattached, and the exudative mass regressed. The exudative masses may disappear for years following the diathermy. No surgical complications were encountered. Unilateral operations of the most severely involved eye, in cases of bilateral disease, resulted in the operated eye being quieter than the unoperated eye. Posterior pole edema and glaucoma frequently occurred in these cases. Applanation pressures were significantly higher than Schiotz. Peripheral uveitis is common and should be suspected in cases of cyclitis without a posterior chorioretinal scar. When steroids produce side effects or fail to control the inflammation of peripheral uveitis, antimetabolites (ie, cyclophosphamide) have proven effective.

BILATERAL STEREOTAXIC LESIONS IN THE MANAGEMENT OF PARKINSONISM AND THE DYSKINESIAS.

Since the establishment of stereotaxic surgery as a therapeutic procedure of value in the management of Parkinsonism and the dyskinesias, most centres specializing in this operation have carried it out bilaterally in some of their patients. However, bilateral stereotaxic surgery has been associated with a certain amount of hazard, somewhat greater than in the case of unilateral operations. There has been a general reluctance to subject these patients to operation on both hemispheres, and the criteria for selection for surgery have been more strictly applied before the second procedure.

Further observations on the effect of surgery on the meniscus of the mandibular joint in rabbits.

Abstract Disks were studied histologically, 8 weeks after unilateral operations. Damage to the meniscus resulted in repair only if the damage was minimal and related to the periphery. When after surgical operation the meniscus remained divided, condylar overgrowth occurred similar to that previously described for complete meniscectomies. Control operations in which the joint cavities were merely opened led to little change of the articular surfaces, except for a small reduction in the cartilage covering of the condyle.

The long-term comparative results of three different lobotomy procedures.

A 5-year follow-up of 116 chronic mentally ill patients, divided into 3 groups each of which was subjected to a different lobotomy procedure (e.g., full bilateral, bimedial, and unilateral operations) disclosed that bimedial lobotomy was superior to either of the other 2 procedures in the treatment of chronic mentally ill patients. "Significant" improvement at 5 years was found in 21 or 65% of the bimedial group, compared with lesser frequencies in the other 2 groups. Also, at 5 years, there was an improvement in work adjustment over that observed at 1 year which was most evident in the bimedial group. The greater relief of anxiety, tension, hostility, and disorganization at 5 years after bimedial operation emphasizes its therapeutic superiority. The number of cases who had one or more convulsive seizures was greater at 5 years than at 1 year. However, only 1 person had status epilepticus and this proved to be fatal.

Effect of bilateral nephrectomy on peripheral vascular reactivity in dogs.

The reactivity of 20 dogs to 0.5 µ/kg of norepinephrine was determined. Eleven dogs were bilaterally nephrectomized ( I), six underwent bilateral sham nephrectomy ( II), and 3 underwent unilateral sham operations followed by contralateral nephrectomy ( III). The results of II and III were pooled for statistical purposes. The average change in reactivity in I was significantly higher than the average change in reactivity in II and III on both the 1st and the 2nd postoperative days. There was no significant difference in blood pressure observed between the two series before the operations.

Regeneration and the moulting cycle in Blattella germanica L. II. Simultaneous regeneration of both metathoracic legs.

At 29�C, 70 per cent. relative humidity, simultaneous removal of both metathoracic legs at the proximal autotomy plane in first instar Blattella germanica results in the appearance at the first moult of either a symmetrical pair of differentiated regenerates or a symmetrical pair of undifferentiated papillae, but not of intermediate stages in differentiation. Papillae at the first moult are followed by differentiated regenerates at the second. Simultaneously produced regenerates are not distinguishable from those arising from unilateral operations.

A comparison of the effects of labyrinthine and cerebellar lesions in the turtle

It is of some interest, in view of the tendency in some quarters to insist upon the essential similarity of the effects of lesions of the labyrinth and of the cerebellum, to ascertain whether this supposed constancy of relationship obtains in animals with a relatively small cerebellum. It may be mentioned that, anatomically, the floor of the mid brain (the pons) and that portion of the roof represented by the vermis cerebelli are phylogenetically old. The lateral lobes of the cerebellum are new developments. The cerebellum of turtles is represented by the vermis. The cerebellum in the genera of turtles used for experiment—–Nanemys and Chrysemys—–is smaller than in the sea turtles. We have already pointed out the fact that there is a great uniformity in the effects of labyrinthine lesions in all animals so far studied and that the effects in the turtle are much the same as in other animals. Ablation of the cerebellum in the turtle does not give rise to the same train of symptoms that is observed after labyrinthine extirpation. We find, in agreement with Fano, that the righting reaction is not abolished by ablation of the cerebellum. There was a small, scarcely noticeable, disturbance of coördination in swimming, manifested most clearly in a slight awkardness in approaching the side of the tank. Occasionally, lack of precision of limb movements on the injured side was observed after unilateral operations. One other symptom was that the animal was rarely or never seen to swim deep in the water after cerebellar removal. Our observations substantiate those of Fano, Bickel and Sergi, whose experiments were done on different genera of turtles. The results on turtles are in substantial agreement also with those of Steiner, Loeb, Bethe and Corso, who report no noticeable motor disturbances in sharks (Scyllium) after cerebellar ablation.