Biomedical subjects

B F Morrey

Publications and source records attributed to B F Morrey.

At least 163 records · Page 9Linked to original sources

PubMed1991

Chronic posterior subluxation and dislocation of the radial head.

The clinical and radiographic features of chronic posterior subluxation or dislocation of the radial head were studied in thirty-four elbows of twenty-seven patients. Three characteristic radiographic types were noted: Type I, subluxation; Type II, posterior dislocation with minimum displacement; and Type III, posterior dislocation with substantial proximal migration of the radius. Follow-up of eighteen patients (twenty-one elbows) revealed that posterior displacement did not usually cause serious functional impairment except for loss of rotation of the forearm. The least common presentation, Type-I subluxation, caused pain and clicking and was associated with late degenerative arthritis. Cosmetic deformity due to prominence of the radial head was also a cosmetic problem, particularly with Type-III dislocation.

Adolescent↗

PubMed1991

Posterolateral rotatory instability of the elbow.

Recurrent posterolateral rotatory instability of the elbow is an apparently undescribed clinical condition that is difficult to diagnose. We treated five patients, ranging in age from five to forty years, who had such a lesion and in whom the instability could be demonstrated only by what we call the posterolateral rotatory-instability test. This test involves supination of the forearm and application of a valgus moment and an axial compression force to the elbow while it is flexed from full extension. The elbow is reduced in full extension and must be subluxated as it is flexed in order to obtain a positive test result (a sudden reduction of the subluxation). Flexion of more than about 40 degrees produces a sudden palpable and visible reduction of the radiohumeral joint. The elbow does not subluxate without provocation. The cause for this condition, we think, is laxity of the ulnar part of the lateral collateral ligament, which allows a transient rotatory subluxation of the ulnohumeral joint and a secondary dislocation of the radiohumeral joint. The annular ligament remains intact, so the radio-ulnar joint does not dislocate. Operative repair of the lax ulnar part of the lateral collateral ligament eliminated the posterolateral rotatory instability, as revealed intraoperatively in our five patients.

Adult↗

PubMed1991

Valgus stability of the elbow. A definition of primary and secondary constraints.

The stabilizing structures of the elbow that resist valgus stress were studied with a tracking device in a model simulating active motion and muscle activity. By varying the order of serial release of the medial collateral ligament complex and removal of the radial head, each structure's contribution to valgus stability against the effect of gravity was determined. In the otherwise intact elbow, absence of the radial head does not significantly alter the three-dimensional characteristics of motion in the elbow joint. Isolated medial collateral release, on the other hand, causes increases in abduction rotation of about 6 degrees-8 degrees in magnitude. Releasing both structures results in gross abduction laxity and elbow subluxation. This study defines the medial collateral ligament (MCL) as the primary constraint of the elbow joint to valgus stress and the radial head as a secondary constraint. This definition facilitates the proper management of patients with radial head fractures and MCL disruption. The comminuted radial head fracture uncomplicated by MCL insufficiency should be treated by excision without the need for an implant and without concern of altering the normal kinematics of the elbow.

Biomechanical Phenomena↗

PubMed1990

Torsional strength reduction due to cortical defects in bone.

This study correlated torsional strength reduction with circular defect size in cortical bone, to define the "stress riser" and "open-section" effect of the defects. The experimental model was developed and verified. Circular defects from 10 to 60% of bone diameter were then created in paired sheep femora and the bones loaded to failure. Contrary to theory, this experimental study suggests that small defects (10%) of bone diameter cause no significant torsional strength reduction. A 20% defect caused a 34% decrease in strength, representing the "stress riser" dimension. Defects between 20 and 60% of bone diameter decreased strength linearly as a function of defect size, and thus no discrete "open section" dimension was identified. For circular defects, we were unable to demonstrate a discrete "open-section" effect at which dramatic strength reduction is observed. These data may prove to be helpful when planning surgery that involves placing defects in bone such as for infection, biopsy, and prosthesis removal. The accepted guideline to avoid defects of greater than 50% of the bone diameter may be too great. Our data reveal this 62% reduction in torque strength and 88% energy to failure exist with a 50% circular defect.

Animals↗

PubMed1990

Glenohumeral muscle force and moment mechanics in a position of shoulder instability.

The three-dimensional orientation of the shoulder girdle musculature was studied in five cadaver shoulders in the position of function at 90 degrees of abduction and 90 degrees of external rotation using a method of computer assisted gross muscle cross-section analysis. The muscle volume, muscle fiber length, and physiological cross-sectional area were obtained by dissecting two specimens. The line of action, the magnitude and orientation of the moment were calculated for each muscle crossing the shoulder joint. The quantitative description of the moment potential of muscle forces influencing shoulder function was thus obtained. The most effective flexors of the shoulder which also appear to resist anterior dislocation in the position studied are the pectoral, the short head of the biceps, coracobrachialis, anterior deltoid, and the subscapularis. Most of the rotator cuff muscles and the posterior deltoid acted as adductors, while the anterior deltoid, long and short head of the biceps, and supraspinatus were abductors. In this position, external rotation was effected by the long head of the biceps, coracobrachialis, and the posterior deltoid, while the majority of the remaining muscles acted as internal rotators.

Aged↗

PubMed1990

Intraarticular pressure and capacity of the elbow.

The compliance, capacity, and the position of minimum intraarticular pressure were measured in 13 thawed, fresh-frozen human elbows. The capacity of the joint capsule was 23 +/- 4 ml. The intraarticular pressure was the lowest at 80 degrees of flexion. Capsular rupture occurred at relatively low intraarticular pressures--80 +/- 42 mm Hg. Knowledge of the capacity of the normal elbow joint combined with the fact that this joint capsule tends to rupture or permit extravasation of fluid into the periarticular soft tissues should be considered when infusing fluids during arthroscopy. Finally, the "resting position" of 80 degrees of flexion minimizes capsular tension and therefore might contribute to the development of joint contracture associated with prolonged immobilization in this position. This would be consistent with the observation that patients with posttraumatic elbow stiffness have an average arc of flexion of 60-90 degrees.

Elbow Joint↗

PubMed1990

Persistent infection after successful arthrodesis for infected total knee arthroplasty. A report of two cases.

Infection in total knee arthroplasty has been reported to range from 1.1% to 12.4%. The literature contains numerous articles on salvage procedures including antibiotic suppression, surgical debridement, resection arthroplasty, arthrodesis, reimplantation, and amputation. Of those knees not reimplantable, a successful arthrodesis is felt by many to give the most predictable long-term results. The majority of literature on arthrodesis for infected total knee arthroplasty concentrates on technical factors and techniques to facilitate fusion. A successful fusion is considered an end point of treatment.

Adult↗

PubMed1990

Glenohumeral elevation studied in three dimensions.

We studied the position and rotational changes associated with elevation of the glenohumeral joint, using a three-dimensional magnetic-field tracking system on nine fresh cadaveric shoulders. The plane of maximal arm elevation was shown to occur 23 degrees anterior to the plane of the scapula. Elevation in any plane anterior to the scapula required external humeral rotation, and maximal elevation was associated with approximately 35 degrees of external humeral rotation. Conversely, internal rotation was necessary for increased elevation posterior to the plane of the scapula. The observed effects of this rotation were to clear the humeral tuberosity from abutting beneath the acromion and to relax the inferior capsular ligamentous constraints. Measurement of the obligatory humeral rotation required for maximal elevation helps to explain the relationship of the limited elevation seen in adhesive capsulitis and after operations which limit external rotation.

Biomechanical Phenomena↗

PubMed1990

Late recurrence of varus deformity after proximal tibial osteotomy.

One hundred thirteen knees with medial gonarthrosis in 95 patients were treated by valgus-producing proximal tibial osteotomy and followed clinically and roentgenographically for a minimum of five years (mean, 6.3 years). Sixty-four knees (57%) were pain free or had only mild discomfort when walking. The standing femorotibial angle decreased from a postoperative average of 9.3 degrees valgus to 7.8 degrees valgus at the final follow-up examination. The tendency for varus recurrence greater than 5 degrees and for medial- or lateral-compartment arthritic progression was evaluated using the Kaplan-Meier survival method. Varus recurred in 18%, lateral-compartment arthritic progression in 60%, and medial-compartment arthritic progression in 83% by nine years after surgery. The probability of arthritic progression is much higher than the probability of significant varus recurrence in long-term roentgenographic follow-up studies of patients with valgus-producing proximal tibial osteotomies.

Adult↗

PubMed1990

Treatment of infection after total knee arthroplasty by débridement with retention of the components.

Thirty-one total knee arthroplasties were followed by infection in twenty-seven patients who were subsequently treated with débridement, retention of the components, and intravenous administration of antibiotics. The results were reviewed retrospectively in an effort to evaluate the function of the prostheses that had been salvaged successfully and to identify the causes of failure of those around which an infection had recurred. At the most recent follow-up (average duration, 8.8 years), infection had recurred around twenty-four (77 per cent) of the thirty-one arthroplasties. Seven knees (23 per cent) remained free of infection. Function remained satisfactory, although revision was subsequently needed in two knees for reasons other than infection. One cause of failure was the duration of the infection before débridement. This averaged twenty-one days for the seven knees in which the prosthetic arthroplasty had been salvaged and thirty-six days for the twenty-four knees in which treatment had failed. Another cause of failure was the type of organism: Staphylococcus aureus had caused the infection in fourteen (58 per cent) of the twenty-four knees in which the treatment failed but in only two of the seven knees in which the prosthetic arthroplasty was salvaged. In addition, eight infections in the first group were resistant to penicillin, whereas both infections in the second group were sensitive to penicillin. The four infections with gram-negative organisms in the series were all in knees in which the treatment failed. All six hinged prostheses that were used failed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

Proximal radioulnar synostosis after repair of distal biceps brachii rupture by the two-incision technique. Report of four cases.

In four cases, proximal radioulnar synostosis developed as a complication of distal biceps tendon reattachment through a two-incision technique. The synostosis was excised in all four cases but recurred in two. In each case, the initial reattachment exposed the bicipital tuberosity of the radius anteriorly and exposed the ulna extraperiosteally through a second incision along its subcutaneous border. This two-incision approach may place the patient at risk for synostosis. If two incisions are to be used for distal biceps tendon reattachment, then a limited muscle-splitting approach through the extensor muscle mass, which avoids exposure of the ulna, may be preferable.

Adult↗

PubMed1990

Arthrodesis of the diabetic neuropathic ankle joint.

At the authors' institution from 1964 to 1984, ankle arthrodesis was performed in 13 patients with insulin-dependent diabetes mellitus who had a history of ankle sprain or fracture. Nine patients were diagnosed by clinical exam as having a peripheral neuropathy; nine patients had roentgenographic evidence of neuropathic arthropathy prior to surgery. Follow-up study with examination and roentgenograms averaged 42 months. Clinical and roentgenographic union was achieved in seven ankles at an average of 16 weeks. Two patients developed a nonunion, three had an amputation, and one died at two months postoperatively. Thirteen complications occurred in eight of the 13 patients (62%). Twenty reoperations, excluding pin removal, were performed in eight patients (62%). A satisfactory result was achieved in only 50% overall and in only 38% of patients with roentgenographic changes of neuropathic arthropathy. Neuropathic arthropathy contributes to the inordinate complication and failure rates. Ankle arthrodesis should be considered with caution in the diabetic patient.

Adult↗

PubMed1990

Post-traumatic contracture of the elbow. Operative treatment, including distraction arthroplasty.

Twenty-six consecutive patients who had post-traumatic contracture of the elbow were treated by operative release alone or by release and distraction arthroplasty, with or without fascial interposition. The type of operative procedure was determined by whether the factors limiting motion were purely extra-articular (extrinsic) or whether they included intra-articular (intrinsic) elements as well. The mean preoperative arc of total motion was 30 degrees (from 63 to 93 degrees of flexion). At follow-up examination, twenty-two to ninety-four months post-operatively, of twenty-five patients, the mean arc of total motion was 96 degrees (from 30 to 126 degrees). There were eight complications in seven (27 per cent) of the patients. Of these, four (avulsion of the triceps tendon, deep infection, and two ulnar-nerve paresthesias) were managed by subsequent operative treatment. The other four complications included drainage from a pin site, which resolved after removal of the pin: a three by two-centimeter skin slough, which spontaneously epithelialized; aseptic resorption of the distal end of the humerus and proximal end of the ulna, which stopped after immobilization and subsequent bracing of the elbow but resulted in moderate instability; and ulnar-nerve paresthesia, which was not operatively treated and persisted. Twenty-four (96 per cent) of the twenty-five patients who were followed for twenty-two months or more were satisfied with the results of the procedure because of the improved facility in carrying out activities of daily living. No patient had increased pain, but two had moderate instability. It was concluded that the results of distraction arthroplasty can be gratifying, but the technique is demanding and the rate of complications is high.

Adolescent↗

PubMed1990

Stabilizing mechanism of the glenohumeral ligaments.

By using the electromagnetic tracking system, the kinematics of the glenohumeral joint in the shoulder complex was studied. With the location of the glenohumeral ligament insertions digitized, the change of ligament length and direction could then be calculated throughout a given movement. This technique provided a useful method for in vitro assessment of the capsuloligamentous constraints of the shoulder joint.

Biomechanical Phenomena↗

PubMed1989

Upper tibial osteotomy for secondary osteoarthritis of the knee.

Of 34 consecutive proximal tibial osteotomies for secondary degenerative arthritis in patients under 40 years of age, 33 were evaluated at least three years (mean 7.5 years) after operation. In all 73% were satisfactory, with four failures in 21 procedures in men and five failures in 12 procedures in women. The primary abnormalities were medial meniscectomy (11), medial and lateral meniscectomy (4), osteochondritis dissecans (3), osteochondritis dissecans with medial meniscectomy (4) and fracture (11). All four knees with both medial and lateral meniscectomy had unsatisfactory results despite obtaining anatomical alignment. Eight patients needed subsequent surgery; five of them had total knee replacement, four within four years of the osteotomy. Proximal tibial osteotomy in younger patients with secondary arthritis gives similar results to those for older patients with primary osteoarthritis. If it fails, this is generally within the first four years after the operation.

Adult↗

PubMed1989

Short-stemmed uncemented femoral component for primary hip arthroplasty.

A short-stemmed femoral implant differing from conventional design assumptions demonstrates that immediate three-point proximal femur fixation is possible without stem fixation. A double-wedged contour and neck shaft angle of 150 degrees help secure immediate stability and lessen an excessive varus moment. Results of 20 patients with at least one year of follow-up study are encouraging. Nineteen (95%) are classified as satisfactory with a Harris hip score of 44.5 before and 97.8 after surgery. One patient was revised for loosening; no patient has thigh pain. The gratifying early results justify further clinical investigation.

Adult↗

PubMed1989

Patellar tendon rupture after total knee arthroplasty.

Between 1973 and 1985, 18 knees in 17 patients were treated for rupture of the patellar tendon after total knee arthroplasty (TKA), accounting for 0.17% of the TKAs performed at the authors' institution during the same interval. Follow-up study was from two and one-half years to four years. Four ruptures occurred in patients who had had a distal patellar realignment procedure, and one occurred after knee manipulation. Only two xenograft reconstructions and two of four staple fixation procedures were successful. After treatment of the patellar tendon rupture, four knees developed deep infection. Avoidance of this complication seems paramount because the results of treatment are discouraging. Patients at high risk at the time of the initial TKA seem to be those with limited preoperative motion in whom surgical exposure is difficult.

Aged↗

PubMed1989

Post-traumatic proximal radio-ulnar synostosis. Results of surgical treatment.

During a period of forty-two years, twenty patients who had a post-traumatic proximal radio-ulnar synostosis were treated by excision of the area of synostosis and various concurrent procedures in an attempt to restore rotation of the forearm. The time from injury to operation averaged eighteen months, and the postoperative follow-up averaged forty months. Results were graded on the basis of improvement in the arc of rotation of the forearm. After excision of the area of synostosis in the fifteen patients for whom data were available, the intraoperative arc of passive rotation averaged 121 degrees. At the most recent follow-up, the range of active rotation averaged 55 degrees for all twenty patients. Four patients had an excellent result; three, good; four, fair; and nine, poor. The outcome of this type of surgical treatment varies, but roughly half of the patients can be benefited.

Adolescent↗