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B F Morrey

Publications and source records attributed to B F Morrey.

At least 19 recordsLinked to original sources
PubMed2006

The effect of the orientation of the radial head on the kinematics of the ulnohumeral joint and force transmission through the radiocapitellar joint.

Background. The treatment of radial head fractures that are not amenable to an open reduction and internal fixation, remains to be a difficult issue. A potential problem with prosthetic replacement of the radial head is the shape of current radial head prostheses. The purpose of this study was to determine the effect of the shape of the radial head on kinematics and load transfer of the elbow. Methods. Kinematics of the elbow and radiocapitellar force transmission were measured in 6 fresh frozen upper extremities. The effect of radial head shape was tested by rotating the head 90 degrees , with a custom-made 'native' radial head prosthesis. 3-D spatial orientation of the ulna showed an average difference in ulnohumeral laxity, between the nominal and 90 degrees conditions, of 0.1 degrees throughout the arc of motion with neutral forearm rotation (maximum: 2 degrees ). Findings. We found an average difference in ulnar axial rotation, of 0.1 degrees (maximum: 1.9 degrees ). No differences showed statistical significance. Radiohumeral joint force was measured and maximally showed a 32 times increase of force in the altered shape conditions. Interpretation. Our results show that the kinematics of the elbow was not affected by altering the shape of the radial head, but it did adversely affect the forces in the radiohumeral joint. This could possibly generate degenerative changes in the elbow.

Biomechanical Phenomena↗
PubMed2005

The kinematic importance of radial neck length in radial head replacement.

Comminuted radial head fractures can be treated with a radial head implant. The effects of lengthening (2.5 mm, 5 mm) and shortening (2.5 mm, 5 mm) of the radial neck, were compared to the nominal length in six human upper extremity cadavers. Total varus-valgus laxity and ulnar rotation were recorded. We hypothesized that restoring the exact length of the radius is important to maintain normal kinematics in the elbow joint. Lengthening or shortening of more than 2.5 mm significantly changed elbow kinematics. Lengthening caused a significant decrease (p < 0.001) in varus-valgus laxity, with the ulna tracking in varus and external rotation. Shortening caused a significant increase in varus-valgus laxity (p < 0.001) and ulnar rotation (p < 0.001), with the ulna tracking in valgus and internal rotation. Our study suggests that a restoration of radial length is important and that axial understuffing or overstuffing the radiohumeral joint by 2.5 mm or more, will alter elbow kinematics.

Aged↗
PubMed2005

Coonrad-Morrey total elbow arthroplasty for tumours of the distal humerus and elbow.

We reviewed 20 patients who had undergone a Coonrad-Morrey total elbow arthroplasty after resection of a primary or metastatic tumour from the elbow or distal humerus between 1980 and 2002. Eighteen patients underwent reconstruction for palliative treatment with restoration of function after intralesional surgery and two after excision of a primary bone tumour. The mean follow-up was 30 months (1 to 192). Five patients (25%) were alive at the final follow-up; 14 (70%) had died of their disease and one of unrelated causes. Local control was achieved in 15 patients (75%). The mean Mayo Elbow Performance Score improved from 22 (5 to 45) to 75 points (55 to 95). Four reconstructions (20%) failed and required revision. Seven patients (35%) had early complications, the most frequent being nerve injury (25%). There were no infections or wound complications although 18 patients (90%) had radiotherapy, chemotherapy or both. The Coonrad-Morrey total elbow arthroplasty provides good relief from pain and a good functional outcome after resection of tumours of the elbow. The rates of complications involving local recurrence of tumour (25%) and nerve injury (25%) are of concern.

Aged↗
PubMed2005

Intrinsic constraint of unlinked total elbow replacements--the ulnotrochlear joint.

BACKGROUND: Many unlinked total elbow replacement designs with radically differing articular geometries exist, suggesting that there is no consensus regarding an optimal design. A feature inherent to the articular design is the intrinsic constraint afforded to the joint by the implant. Our aim was to compare the intrinsic constraints of unlinked implants with that of the normal ulnotrochlear joint. METHODS: We tested twelve cadaveric ulnotrochlear joints with a custom-made multiple-axis materials testing machine. With compressive loads ranging from 10 to 100 N, the joints were moved in either valgus or varus directions at 90 degrees of flexion. The ulnotrochlear components from a single example of five medium-sized unlinked elbow replacements (Ewald, Kudo, Pritchard ERS, Sorbie-Questor, and Souter-Strathclyde) were also tested. The recorded measurements included the torques and forces, angular displacement, and axial displacement of the humerus relative to the ulna. RESULTS: In general, the peak torque and the constraint ratio significantly increased with increasing compressive load for the implants as well as for the normal elbow. In valgus displacement, the Souter-Strathclyde implant had the highest and the Sorbie-Questor had the smallest peak torque and the Souter-Strathclyde had the highest and the Ewald had the smallest constraint ratio. In varus displacement, the Kudo had the highest and the Ewald had the smallest peak torque and constraint ratio. CONCLUSIONS: The constraint ratio is a characteristic that is useful for describing elbow joint behavior and for comparing the behavior of implants with that of the human elbow. Of the unlinked implants tested, the Souter-Strathclyde and Kudo prostheses most closely approximated the behavior of the human elbow joint. Implants that resemble the human elbow in appearance do not replicate normal behavior consistently, whereas other implants that do not resemble the human elbow closely do not deviate markedly from human behavior. Thus, much basic information about elbow form and function is needed to improve the performance of total elbow prostheses.

Aged↗
PubMed2005

Total elbow arthroplasty after previous resection of the radial head and synovectomy.

We examined the effects of previous resection of the radial head and synovectomy on the outcome of subsequent total elbow arthroplasty in patients with rheumatoid arthritis. Fifteen elbows with a history of resection and synovectomy were compared with a control group of patients who had elbow arthroplasty with an implant of the same design. The mean age in both groups was 63 years. In the study group, resection of the radial head and synovectomy had been undertaken at a mean of 8.9 years before arthroplasty. The mean radiological follow-up for the 13 available patients in the study group was 5.89 years (0.3 to 11.0) and in the control group was 6.6 years (2.2 to 12.6). There were no revisions in either group. The mean Mayo elbow performance score improved from 29 to 96 in the study group, with similar improvement in the control group (28 to 87). The study group had excellent results in 13 elbows and good results in two. The control group had excellent results in seven and good results in six. Our experience indicates that previous resection of the radial head and synovectomy are not associated with an increased rate of revision following subsequent arthroplasty of the elbow. However, there was a higher rate of complication in the study group compared with the control group.

Aged↗
PubMed2005

Ligamentous repair and reconstruction for posterolateral rotatory instability of the elbow.

We describe the intermediate results of lateral ligamentous repair or reconstruction for posterolateral rotatory instability of the elbow. Between 1986 and 1999, we performed 12 direct repairs and 33 ligament reconstructions with a tendon autograft. One patient was lost to follow-up and 44 were retrospectively studied at a mean of six years (2 to 15). Surgery restored stability in all except five patients. In two the elbow became stable after a second procedure. The mean post-operative Mayo elbow performance score was 85 points (60 to 100). The result was classified as excellent in 19, good in 13, fair in seven and poor in five patients. Thirty-eight patients (86%) were subjectively satisfied with the outcome of the operation. Better results were obtained in patients with a post-traumatic aetiology (p = 0.03), those with subjective symptoms of instability at presentation (p = 0.006) and those who had an augmented reconstruction using a tendon graft (p = 0.04). Reconstruction using a tendon graft seems to provide better results than ligament repair and the results do not seem to deteriorate with time. The outcome of this procedure is less predictable in patients with no subjective instability.

Adolescent↗
PubMed2004

Anatomical considerations of the radius.

Most radial head prostheses do not seem to be based on anatomic data. This may be due partly to the great variation of radial morphology. More importantly, few articles report on the dimensions of the radius. Authors have mainly studied dimensions of the radial head, with less emphasis to the relationship with the rest of the radius. Dimensions of, and relationship between, the proximal and the rest of the radius were measured on 27 fresh-frozen cadaveric upper extremities. Radial head, articulating surface, diaphysis, and distal radius were measured. Angles between the radial neck and diaphysis were defined and calculated. Axes of the distal and proximal radius were defined and radial torsion was calculated. Repeated measures were done by two observers in ten specimens. Inter- and intra-class correlation coefficients were very acceptable. Radial dimensions were found to be highly variable. Calculation of radial torsion showed the largest range. The average torsion was 54 degrees (range = 23-78 degrees). Radial length was 235 mm (range = 207-269 mm). Radial neck length was 13 mm (range = 9-19 mm). We found an average proximal diaphysis-neck angle of 17 degrees (range = 6-28 degrees). End to end-neck angle was 13 degrees (range = 4-22 degrees). Our findings indicate that even with a perfectly anatomical prosthesis, restoration of the anatomical situation can only be achieved when the implant is placed in the correct position. Instrumentation should be developed to allow accurate and reproducible implantation. The measurements we provide may aid this development.

Aged↗
PubMed2004

Decrease in particle-induced osteolysis in obese (ob/ob) mice.

There may be variability in the susceptibility of different individuals to osteolysis from wear debris, and it is not clear whether some individuals may have a genetic predisposition for a more marked osteolytic response. The purpose of this study in mice was to determine whether genetically determined obesity can alter the response to particulate debris. Polyethylene particles were implanted onto the calvaria of seven wild-type mice and seven obese mice (ob/ob). Calvaria from unimplanted wild-type and obese mice served as controls. Calvaria were harvested after 7 days, stained with toluidine blue and for tartrate-specific alkaline phosphatase, and analyzed by histomorphometry. The osteoclast number per mm total bone perimeter was 8.000+/-3.464 in wild-type animals with particles and 2.857+/-1.676 in ob/ob animals with particles (p=0.002; Fisher's PLSD). Bone resorption was 1.895+/-0.713 mm/mm(2) in wild-type animals with particles and 1.265+/-0.494 mm/mm(2) in ob/ob animals with particles (p=0.0438; Fisher's PLSD). Particles induced a diminished osteolytic response in genetically determined obese mice, suggesting that obesity may have a protective role against particle-induced bone resorption-similar to obesity and osteoporosis. These important new findings may help to stimulate clinical studies which may define criteria to better identify patients at risk to develop particle-induced osteolysis.

Animals↗
PubMed2004

The effect of the orientation of the noncircular radial head on elbow kinematics.

OBJECTIVE: The objective of this study was to identify the effect of radial head shape and orientation on elbow kinematics in the otherwise intact elbow. DESIGN: Biomechanical study, analyzing simulated active motion of cadaveric arms. BACKGROUND: A discrepancy exists between the noncircular anatomy of the radial head and radial head prostheses. The effect of radial head shape is unknown. METHODS: Kinematic effects of radial head shape were tested in six fresh-frozen upper extremities. A custom-made native radial head prosthesis was used to simulate altered shape conditions, by rotating the radial head 90 degrees. Three-dimensional spatial orientation of the ulna was recorded, during simulated active motion. A three factor ANOVA was used to compare (a) nominal and 90 degrees oriented conditions, (b) throughout the flexion arc (c) in three forearm positions (P < 0.05). Post-hoc Tukey tests were done to assess significance. RESULTS: No significant effect of altering radial head shape was found on total ulnohumeral laxity and angulation during gravity valgus stress. We did find a significant effect on total ulnar axial rotation and rotation during gravity valgus stress. CONCLUSION: The outer shape of the radial head seems to change rotation of the ulna during flexion-extension in an otherwise intact elbow. RELEVANCE: The shape of the radial head effects intact elbow kinematics. Clinical importance of this finding is clear. If a sub-optimally placed radial head prosthesis were to be used in an otherwise intact elbow, the elbow could be at risk for early ulnohumeral arthritis.

Biomechanical Phenomena↗
PubMed2004

Dislocation after long-necked total hip arthroplasty.

Dislocation after total hip arthroplasty is problematic and not completely understood. Skirted long-necked implants have been used to reestablish soft tissue tension with the assumption that their use will reduce dislocation. It is unknown whether the dislocation rates with long-necked implants are different than those with standard neck length devices. The records of 250 consecutive total hip arthroplasties were reviewed, 125 primary and 125 revision, in which long-necked femoral prostheses were used. A matched control sample with standard neck length prostheses was defined. Dislocation rates and radiographic indices of leg length were calculated and compared with the control group. Dislocation rates in the long-necked groups were 10.6% and 18% for primary and revision surgeries, respectively. These rates were significantly higher than the rates seen in standard neck length controls (1.6% and 10%, respectively). There was no difference in leg-length discrepancy between long-necked prostheses and standard neck length matched controls. Long-necked prostheses are associated with higher rates of dislocation after total hip arthroplasty. The higher rates may be attributable to impingement of the neck, inadequate restoration of soft tissue tension, and/or other factors. Although this study cannot claim to have shown a cause and effect relationship between the skirted neck and dislocation, the association between the two variables is clearly shown.

Arthroplasty, Replacement, Hip↗
PubMed2004

Proximal ulnar reconstruction with strut allograft in revision total elbow arthroplasty.

BACKGROUND: The growing frequency of joint arthroplasty has led to increasing numbers of patients requiring revision surgery. In the treatment of a failed total elbow arthroplasty not associated with infection, one of the main issues is poor or absent proximal ulnar bone stock due to osteolysis. We report our experience with the use of strut allograft reconstruction of the proximal part of the ulna as an adjunct to revision total elbow arthroplasty with a noncustom implant. Our aim was to better define the indications, outcomes, and complications of this technique in a population of patients with a failed total elbow arthroplasty. METHODS: We reviewed the cases of patients with aseptic failure of a total elbow replacement and proximal ulnar bone deficiency who were treated with allograft bone struts. The patients had had an average of 2.5 (range, one to four) prior open osseous operations addressing the elbow joint. In addition to revision of the prosthetic components, the deficient bone stock was treated with allograft strut grafts in one of four ways: (1) discrete cortical defects were contained, (2) periprosthetic fractures were splinted, (3) deficient triceps attachments were reconstructed, and (4) expanded segments were augmented with struts and filled with impaction graft. Twenty-one patients (twenty-two elbows) were followed for an average of four years (range, two to eleven years). RESULTS: The mean Mayo Elbow Performance Score improved from 34 points preoperatively to 79 points at the time of the latest follow-up. The scores for pain, stability, and activities of daily living improved most; there was little change in motion. Complications, consisting of four soft-tissue and four osseous problems, occurred in eight patients. Three patients had incorporation of 26% to 50% of the graft; five, 51% to 75%; and fourteen, 76% to 100%. CONCLUSIONS: Most deficiencies of proximal ulnar bone stock and fractures complicating revision total elbow surgery can be treated with allograft strut grafting. Although the complication rate is high, this technique is suitable for discrete cortical lesions, periprosthetic fractures, and an expanded proximal part of the ulna, which also requires augmentation with impaction grafting. The technique has been unreliable, however, in restoring deficient olecranon bone stock.

Arthroplasty, Replacement↗
PubMed2004

Detrimental effects of overstuffing or understuffing with a radial head replacement in the medial collateral-ligament deficient elbow.

BACKGROUND: Comminuted radial head fractures associated with an injury of the medial collateral ligament can be treated with a radial head implant. We hypothesized that lengthening and shortening of the radial neck would alter the kinematics and the pressure through the radiocapitellar joint in the medial collateral ligament-deficient elbow. METHODS: The effects of lengthening (2.5 and 5 mm) and shortening (2.5 and 5 mm) of the radial neck were assessed in six human cadaveric upper extremities in which the medial collateral ligament had been surgically released. The three-dimensional spatial orientation of the ulna was recorded during simulated active motion from extension to flexion. Total varus-valgus laxity and ulnar rotation were measured. Radiocapitellar joint pressure was assessed with use of pressure-sensitive film. RESULTS: Radial neck lengthening or shortening of >/=2.5 mm significantly changed the kinematics in the medial collateral ligament-deficient elbow. Lengthening caused a significant decrease (p < 0.05) in varus-valgus laxity and ulnar rotation (p < 0.05), with the ulna tracking in varus and external rotation. Shortening caused a significant increase in varus-valgus laxity (p < 0.05) and ulnar rotation (p < 0.05), with the ulna tracking in valgus and internal rotation. The pressure on the radiocapitellar joint was significantly increased after 2.5 mm of lengthening. CONCLUSIONS: This study suggests that accurate restoration of radial length is important and that axial understuffing or overstuffing of the radiohumeral joint by >/=2.5 mm alters both elbow kinematics and radiocapitellar pressure. CLINICAL RELEVANCE: This in vitro cadaver study indicates that a radial head replacement should be performed with the same level of concern for accuracy and reproducibility of component position and orientation as is appropriate with any other prosthesis.

Aged↗
PubMed2003

[Differential arthroplasty and endoprosthesis indications in rheumatoid arthritis of the elbow joint].

Management of patients with rheumatoid arthritis of the elbow has changed significantly over the last several years. From a medical standpoint, the disease-modifying agents have decreased the number of patients requiring a synovectomy. When synovectomy is indicated, arthroscopic synovectomy has lessened the morbidity of this procedure, but the long-term effectiveness as a definitive reconstructive procedure has yet to be determined. Both coupled and uncoupled elbow joint replacements have emerged as reliable interventions for this diagnosis. Mayo's experience with 78 patients with rheumatoid arthritis undergoing total elbow arthroplasty has revealed a satisfactory outcome of approximately 92% at 12 years. The complication rate is approximately 15% consisting primarily of delayed avulsions or deficiency of the triceps tendon (2%), deep infection (2%), and ulnar nerve irritation (3%).

Arthritis, Rheumatoid↗
PubMed2003

Partial posteromedial olecranon resection: a kinematic study.

BACKGROUND: The posteromedial aspect of the olecranon process is a site of impingement and subsequent osteophyte development in throwing athletes. Treatment with débridement, with resection of osteophytes and varying amounts of normal olecranon bone, is common. We found no reports in the literature concerning the effects of resecting different amounts of normal bone from the posteromedial aspect of the olecranon. We hypothesized that excessive resection would increasingly alter elbow kinematics and that an optimum amount of olecranon resection could be identified. METHODS: We investigated the kinematic effects of increasing valgus and varus torques and posteromedial olecranon resections, in twelve cadaveric elbows, with use of an electromagnetic tracking device. Two valgus and two varus torques were applied, and three sequential resections were performed in 3-mm steps from 0 mm to 9 mm. Statistical analyses included paired t tests, 95% confidence intervals, a one-factor analysis of variance with repeated measures, and a post hoc test when significance was established. RESULTS: Sequential partial resection of the posteromedial aspect of the olecranon resulted in stepwise increases in valgus angulation with valgus torque. Clear differences were seen at each level of resection. A pattern of increased valgus angulation also was seen in association with increased valgus torque. Increased valgus torque resulted in a trend toward increased axial internal rotation of the ulna, whereas increased osseous resection resulted in a decrease in the absolute degree of internal rotation or, in some specimens, increased external rotation. CONCLUSIONS: Although no single critical amount of olecranon resection was identified, valgus angulation of the elbow increased in association with all resections, with a marked increase occurring in association with a 9-mm resection. Our findings challenge the rationale of removing any amount of normal olecranon bone in throwing athletes as doing so may increase strain on the medial collateral ligament. The implications for the professional throwing athlete are important, and we recommend that bone removal from the olecranon be limited to osteophytes, without the removal of normal bone.

Aged↗
PubMed2002

Effect of pregnancy on joint contracture in the rat knee.

As there is evidence that ligamentous laxity is affected by the female hormones, we hypothesized that hormonal changes occurring during pregnancy could have a therapeutic role in preventing the development of a joint contracture. Knee joint contractures were created in pregnant and nonpregnant rats. After 2 wk of immobilization, the degree of contracture was measured with structural properties of the medial collateral and anterior cruciate ligaments and the pubic symphysis. Although not statistically significant, there was a general trend toward reduced contracture in pregnant compared with nonpregnant rats. Cutting the posterior capsule significantly decreased contracture for both the pregnant and nonpregnant groups, confirming the contribution of capsular structures to contracture. Ultimate loads of the medial collateral and anterior cruciate ligaments significantly decreased after immobilization compared with control, but there was no significant effect due to pregnancy. Stiffness and ultimate load of the pubic symphysis were not significantly different between pregnant and nonpregnant groups. The trend toward reduced contracture with pregnancy points toward a possible therapeutic role for female hormones in the prevention of postoperative and/or posttraumatic joint contracture.

Animals↗
PubMed2002

Synovial osteochondromatosis of the elbow.

We present 12 patients with synovial osteochondromatosis of the elbow treated by synovectomy. Histological review showed that seven cases were primary and five secondary osteochondromatosis. The patients with primary disease had a mean improvement in the flexion arc from a preoperative value of 40 degrees to 123 degrees to 5 degrees to 128 degrees when reviewed at a mean of nine years after operation. The secondary group had a mean improvement in the flexion arc from a preoperative value of 21 degrees to 98 degrees to 4 degrees to 131 degrees at a mean of 6.8 years after operation. There was recurrence in two of seven patients in the primary group and three of five in the secondary group. Osteoarthritis developed in six elbows in the primary and in three in the secondary group. Osteoarthritis secondary to synovial osteochondromatosis is progressive. In the established condition, the distinction between primary and secondary disease may be of greater histological than clinical relevance.

Adolescent↗
PubMed2001

[Endoprosthetic joint replacement of the contracted elbow joint].

In a retrospective study 14 patients were reviewed 63 months after the implantation of a semi-constrained total elbow prosthesis in fourteen stiff or ankylosed elbows with a preoperative range of elbow motion of 30 degrees or less. The result, according to the Mayo Elbow Performance score, was excellent for four elbows, good for four, fair for one, and poor for five. The average arc of flexion improved from 7 to 68 degrees postoperatively with an average increase of 34 degrees in flexion, and 27 degrees in extension. There were seven complications affecting seven of the 14 elbows and four of these seven elbows underwent a revision procedure. Replacement for a stiff elbow is the least predictable, has the lowest overall rate of success and highest complication rate, than any other procedure. Nevertheless, these disadvantages must be placed in the context of alternative intervention options. The semiconstrained total elbow arthroplasty seems to be a useful option for patients older than 50 years with intrinsic stiffness involving more than 50% of the articular surface and with an ankylosed or very stiff elbow.

Adult↗