Biomedical subjects

B F Morrey

Publications and source records attributed to B F Morrey.

At least 127 records · Page 7Linked to original sources

PubMed1993

Stabilising function of the biceps in stable and unstable shoulders.

We studied the contributions of the long and short heads of the biceps (LHB, SHB) to anterior stability in 13 cadaver shoulders. The LHB and SHB were replaced by spring devices and translation tests at 90 degrees abduction of the arm were performed by applying a 1.5 kg anterior force. The position of the humeral head was monitored by an electromagnetic tracking device with or without an anterior translational force; with 0 kg, 1.5 kg or 3 kg loads applied on either LHB or SHB tendons in 60 degrees, 90 degrees or 120 degrees of external rotation; and with the capsule intact, vented, or damaged by a Bankart lesion. The anterior displacement of the humeral head under 1.5 kg force was significantly decreased by both the LHB and SHB loading in all capsular conditions when the arm was in 60 degrees or 90 degrees of external rotation. At 120 degrees of external rotation, anterior displacement was significantly decreased by LHB and SHB loading only when there was a Bankart lesion. We conclude that LHB and SHB have similar functions as anterior stabilizers of the glenohumeral joint with the arm in abduction and external rotation, and that their role increases as shoulder stability decreases. Both heads of the biceps have been shown to have a stabilising function in resisting anterior head displacement, and consideration should therefore be given to strengthening the biceps during rehabilitation programmes for chronic anterior instability of the shoulder.

Analysis of Variance↗

PubMed1993

Capsular properties of the shoulder.

The purpose of this study was to determine the structural properties of the capsule of the glenohumeral joint. Twelve fresh frozen cadaveric shoulders were studied. Capsular strips were prepared from four different sites (anterior, posterior, superior, and inferior) of the capsule. One end of the capsular sections was left attached to the humerus, and the other excised was fixed in a clamp of an Instron universal testing machine. Maximum load, strength (maximum stress), and modulus of elasticity of these four capsular portions were measured. The most common mode of failure was tear at the midsubstance (68%), followed by tear at the clamp-capsule junction (23%), and detachment from the humerus (9%). The posterior capsule (1.0 +/- 0.4 mm) was thinner than the anterior (1.8 +/- 0.3 mm), superior (1.6 +/- 0.4 mm), and inferior capsule (1.5 +/- 0.3 mm). Among the four portions of the capsule, the posterior capsule showed the greatest strength (216.6 +/- 58.2 kg/cm2) and modulus of elasticity (683.1 +/- 228.8 kg/cm2), whereas the superior capsule showed the least strength (82.4 +/- 33.5 kg/cm2). There were no significant differences in maximum load. The greater strength of the posterior capsule may be one explanation for the low incidence of posterior shoulder dislocation.

Biomechanical Phenomena↗

PubMed1993

Bulk effect of rotator cuff on inferior glenohumeral stability as function of scapular inclination angle: a cadaver study.

Eleven fresh cadaver shoulders were studied to determine the static contribution (bulk effect) of the rotator cuff on inferior glenohumeral stability provided by scapular inclination. All musculature, including the rotator cuff, was removed. The position of the humerus relative to the scapula was recorded using an electromagnetic tracking device under conditions of no force and 1.5 kg of inferior translation force applied to the humerus, with the arm in the hanging position (sulcus test) and then in 90 degrees abduction (Abduction-Inferior Stability test = ABIS test), with the scapula inclined referable to the vertical line at -15 degrees, 0 degrees, 15 degrees and 30 degrees in the sulcus test and at 15 degrees, 30 degrees, 45 degrees and 60 degrees in the ABIS test. In the sulcus test without load, all shoulders dislocated at scapular inclination angles of -15 degrees and 0 degrees, whereas no shoulders dislocated at 30 degrees. The angle of scapular inclination had a significant effect on humeral head positions (p < 0.0001), with the head position at -15 degrees and 0 degree being lower than at 15 degrees, which was lower than at 30 degrees. In the ABIS test, none of the shoulders dislocated, although the effect of the angle of scapular inclination was significant (p < 0.0001), with the position of the humeral head being higher at 15 degrees than at other angles of inclination. Comparison of these data and previously reported data with the cuff intact showed no significant effect of rotator cuff removal on humeral head position and displacement in both tests. Therefore, we conclude that the static condition of the rotator cuff has no significant effect on the stabilizing function of scapular inclination. The stabilizing mechanism of scapular inclination seems to be associated with the bony configuration and/or anatomy and biomechanical properties of the superior capsuloligamentous structures.

Adult↗

PubMed1993

Hip and knee replacement in osteogenesis imperfecta.

Five total hip and three total knee arthroplasties were performed, from 1969 to 1990, in six patients who had osteogenesis imperfecta. The patients who had a hip arthroplasty were followed for a mean of seven years, and those who had a knee arthroplasty, for a mean of ten years. Postoperatively, all had relief of pain and were able to walk; one patient used a walker and two used a cane. The only postoperative complication was an intrapelvic protrusion of the acetabular component six years after a bipolar hip replacement.

Female↗

PubMed1993

Kinematic and stability of the Norway elbow. A cadaveric study.

We investigated the effect of simulated muscle loading and the contribution of the radial head to stability of the Norway elbow in 6 cadavers using an electromagnetic tracking device. The kinematics of the elbow after implantation of the prosthesis were similar to the intact elbow in their valgus-varus orientation, however, the forearms were slightly externally rotated, probably due to a small amount of external rotation of the humeral components at the time of implantation. The valgus-varus laxity limit of the implants were greater than in the intact specimens averaging 8.0 and 5.6 degrees, respectively. Simulated muscle loading stabilized both the intact and the Norway elbows. Excision of the radial head after implant arthroplasty increased their valgus-varus laxity, suggesting that preservation of the radial head may be indicated if it is not too severely involved by the underlying disease process. The laxity permitted by the prosthesis articulation is greater than that measured after implantation of the Norway arthroplasty. This suggests that the prosthesis may behave as an unconstrained arthroplasty. This should minimize the stress experienced by the bone-cement interface and may reduce the incidence of loosening. The laxity of the elbows after joint arthroplasty were only slightly greater than normal, possibly explaining the low incidence of prosthesis dislocation which has been observed with clinical use.

Aged↗

PubMed1993

Distraction arthroplasty. Clinical applications.

The concept of a hinged-joint distraction device appears to have broad clinical application in those circumstances in which both joint motion and joint stability are simultaneous treatment goals. Under these circumstances, difficult clinical conditions can be effectively treated with the judicious application of this device.

Arthroplasty↗

PubMed1993

Reoperation after condylar revision total knee arthroplasty.

Reasons for reoperation after knee revision surgery are implant loosening, sepsis, extensor mechanism problems, fractures of bone or prosthetic components, wear debris, and limited range of motion. The purpose of this study was to review the complications requiring reoperation in a large number of condylar revision total knee arthroplasties to determine the incidence and outcome after treatment. Six hundred fifty-five condylar revision total knee arthroplasties performed during a ten-year period were retrospectively reviewed. Forty-six knees without a history of arthroplasty infection required a total of 60 reoperations after the revision surgery. A reoperation was performed for extensor mechanism or patellar problems in 19 knees (41%), component loosening in ten knees (22%), deep infection in nine knees (20%), wound problems in nine knees (20%), tibiofemoral instability in eight knees (17%), limited range of motion in four knees (8%), and particulate debris synovitis in one knee (2%). All patients were observed for an average of 7.5 years. Twenty-four knees (52%) were considered clinical failures because of pain, limited motion, instability, and sepsis. Awareness of these failure modes may help to prevent complications by strict attention at the time of revision surgery to protection of the patellar tendon attachment and collateral ligaments, balancing of the extensor mechanism, preservation of the patellar blood supply, proper component position and sizing, restoration of the mechanical axis, and use of more constrained implant designs.

Adult↗

PubMed1993

Distal femoral varus osteotomy for painful genu valgum. A five-to-11-year follow-up study.

From 1978 until 1984, 23 patients (24 knees) were treated with varus producing distal femoral osteotomy for painful, lateral compartment osteoarthrosis. Evaluation at five to 11 years (average, 8.3 years) included orthopedic examination, calculation of the Hospital for Special Surgery (HSS) knee score, and standing knee roentgenograms. Based on the objective knee scores, 71% of the patients had good or excellent results, with no difference in those followed for longer periods. Complications occurred in 63% of the cases, including nonunion (25%) and loss of correction (21%). Both complications were associated exclusively with staple fixation, which was performed during the period of this study and is now known to be inadequate to fix this osteotomy. Despite increasing morbidity rates, these complications did not appear to influence the ultimate result. A statistically significant prognostic factor was the severity of the disease as reflected by the pre- and postoperative knee scores. Further, the degree of correction was a function of the initial deformity. At follow-up evaluation 13% of the knees had been converted to a total knee replacement.

Adult↗

PubMed1993

Long-term evaluation of hip arthroplasty in patients with an ipsilateral knee arthrodesis.

Hip arthroplasty with an ipsilateral knee arthrodesis occurs infrequently but does raise concern regarding surgical technical difficulties, dislocation, sepsis, and long-term loosening. Sixteen patients were evaluated 7.5 years (average period) after surgery. Technical difficulties were not prohibitive. No dislocation or revision was necessary in any of the cases. Two patients died as a result of unrelated sepsis from an infected knee. Loosening and protrusio of the acetabulum occurred in two patients. Hip arthroplasty in patients with a fused knee does not incur undue risk of loosening or instability and can provide long-term good function and pain relief. Patients with multiple joint arthroplasties, in whom concurrent sepsis occurs, can have devastating results.

Arthrodesis↗

PubMed1993

Results of meniscectomy in the knee with anterior cruciate ligament deficiency.

Sixty-three knees in 62 patients with insufficiency of the anterior cruciate ligament (ACL) were treated by arthroscopic partial or total meniscectomy without ligament reconstruction. The implications of this sequence of treatment with this combination of pathologies was documented. At 4.5 years after meniscectomy, 84% of the knees were subjectively improved and 10% were subjectively worse. Sixty-eight percent of the patients had persistent knee pain and 52% had episodes of giving way. Roentgenographic evidence of osteoarthrosis was present in 65% of 34 knees at 4.4 years after operation. Additional surgery was required in 24% of the knees. Meniscectomy without a stabilization procedure should be performed only infrequently in knees with deficient ACL.

Acute Disease↗

PubMed1992

Origin of the medial ulnar collateral ligament.

The anatomic features of the origin of the anterior medial collateral ligament of the elbow were studied in 10 cadaver elbows to determine the percentage of the medial epicondyle that can be removed without violating the ligament, and whether or not this ligament attaches to the condyle as well as to the epicondyle. In all specimens the anterior medial collateral ligament originated exclusively from the anteroinferior surface of medial epicondyle and had no attachment to the condyle. Only 20% of the width of the medial epicondyle in the coronal plane can be removed without violating a portion of the origin of the anterior medial collateral ligament, an essential stabilizer of the elbow. Excision of the entire epicondyle for ulnar neuropathy would completely detach this ligament from its origin and might therefore potentiate instability. Since the ligament originates on the anteroinferior surface of the epicondyle, more bone can be removed with less violation of the anterior medial collateral ligament origin if the plane of the osteotomy lies between the sagittal and coronal planes.

Cadaver↗

PubMed1992

Total knee arthroplasty in patients with prior ipsilateral hip fusion.

Sixteen total knee arthroplasties performed between 1977 and 1985 in 13 patients with prior ipsilateral hip arthrodesis or ankylosis were studied to determine the preferred sequence and long-term follow-up of procedures in this clinical setting. Twelve of 16 underwent fusion takedown and total hip arthroplasty prior to knee replacement. The average age at total knee arthroplasty was 52.7 years and the average time from hip fusion to total knee arthroplasty was 36.3 years. Mean follow-up after total knee arthroplasty was 5.5 years (range, 2.3 to 10 years). The Hospital for Special Surgery knee score increased from a mean of 31.8 preoperatively to 72.2 after surgery. In patients who had conversion of the hip fusion prior to knee replacement, knee scores were 28 before and 72.5 after both procedures. Patients who retained their hip fusion had mean scores of 43.5 and 72.1, respectively. None of the knees has been removed and 14 of 16 had no pain at last follow-up. One had mild pain and one had moderate pain attributed to pes anserine bursitis. Although the numbers are small, this experience reveals that takedown of the fusion with total hip arthroplasty is an effective technique before performing the knee replacement. Though successful in some instances, the experience is too small to show that if hip fusion is in good position, knee replacement without fusion takedown is acceptable.

Adolescent↗

PubMed1992

Complications with revision of the femoral component of total hip arthroplasty. Comparison between cemented and uncemented techniques.

The intraoperative and early postoperative complications of femoral component revision surgery in a group of 94 treated with a cemented femoral implant and 91 treated with a specific (Bias, Zimmer International, Warsaw, IN) uncemented femoral implant were assessed. Follow-up of at least 2 years for both groups was obtained, averaging 4.5 years and 3.2 years, respectively. The Harris hip score was 45 and 81 before and after the cemented revision and 42 and 84 for the uncemented procedure. The overall complication rate was 41% and 34%, respectively, which is not statistically different. The major differences consist of radiographic evidence of probable loosening in 53% of the cemented population and at least 2 mm of subsidence in 45% of the uncemented group. Fracture occurred in 3% and 18%, respectively, and caused failure in one with cemented and three with uncemented revisions. The reoperation rate was 15% and 12%, respectively. In these patient populations, uncemented femoral revision was a satisfactory technique, having a complication rate comparable to and radiographic features more favorable than what was present with the cemented revision procedure. Long-term follow-up is necessary to determine more fully the role of uncemented implants for femoral component revision.

Cementation↗

PubMed1992

Venous thromboembolism associated with hip and knee arthroplasty: current prophylactic practices and outcomes.

Joint registry and hospital data bases for 5,024 total hip and total knee arthroplasties done between 1986 and 1988 at the Mayo Clinic were used to study prophylactic measures and frequency of symptomatic deep venous thrombosis and pulmonary embolism. In virtually all patients, graduated compression stockings were used, with or without another type of prophylaxis. Only 44 of 3,115 patients who underwent hip arthroplasty (1.4%) and 32 of 1,909 patients who underwent knee arthroplasty (1.7%) had definite or probable deep venous thrombosis or pulmonary embolism. Death definitely or possibly attributable to pulmonary embolism occurred in 11 patients who underwent hip arthroplasty (0.35%) and 1 patient who underwent knee arthroplasty (0.05%). Although patients with a history of deep venous thrombosis or pulmonary embolism were more likely to receive warfarin than were patients without such a history, the relative risk of symptomatic deep venous thrombosis or pulmonary embolism in patients who underwent hip arthroplasty and received warfarin postoperatively was approximately half that in patients who received other types of prophylaxis. The risk of death from pulmonary embolism was similarly diminished in the group that received warfarin. The lower rates of these complications in the patients who received warfarin support the prophylactic use of this agent after total hip arthroplasty.

Aspirin↗

PubMed1992

Kinematics of semi-constrained total elbow arthroplasty.

We used 11 cadaver elbows and a three-dimensional electromagnetic tracking device to record elbow movements before and after implantation of a 'loose-hinged' elbow prosthesis (modified Coonrad). During simulated active motion there was a maximum of 2.7 degrees (+/- 1.5 degrees) varus/valgus laxity in the cadaver joints. This increased slightly after total elbow arthroplasty to 3.8 degrees (+/- 1.4 degrees). These values are lower than those recorded for the cadaver joints and for the prostheses at the limits of their varus/valgus displacements, indicating that both behave as 'semi-constrained' joints under physiological conditions. They suggest that the muscles absorb some of the forces and moments that in a constrained prosthesis would be transferred to the prosthesis-bone interface.

Biomechanical Phenomena↗

PubMed1992

Primary degenerative arthritis of the elbow. Treatment by ulnohumeral arthroplasty.

Degenerative arthritis of the elbow is a poorly recognised condition, usually seen in a middle-aged man with an occupation or activity which involves the repetitive use of his dominant arm. Flexion contracture and pain at terminal extension are common presenting features. Fifteen patients were reviewed at a mean of 33 months after debridement by ulnohumeral arthroplasty. Fourteen had good relief of pain, elbow extension had improved by an average of 11 degrees and elbow flexion by 10 degrees. On an objective scale 12 of the 15 patients had good or excellent results and 13 (87%) felt that they were improved by the operation.

Adult↗

PubMed1992

Classification and treatment of coronoid process fractures.

Fractures of the coronoid process are rare as isolated injuries and usually are associated with significant, sometimes devastating trauma to the elbow. The classification system based on the degree of involvement has proven helpful to estimate prognosis and to help guide treatment. Severe fractures are generally associated with instability and portend a poor prognosis. Treatment by distraction, external fixation, and early motion has been encouraging.

Adolescent↗

PubMed1992

Posttraumatic stiffness: distraction arthroplasty.

Loss of motion after elbow trauma is a common complication. At times, the limitation of motion may significantly impair function. Options to improve posttraumatic motion by surgery depend on whether the joint surface has been severely involved (intrinsic vs extrinsic contracture). Increasing experience with the surgical release of the posttraumatic stiff elbow has been enhanced by the use of distraction with or without interposition arthroplasty. Current experience suggests that approximately 85% of patients will be satisfactorily treated with surgical intervention.

Arthroplasty↗