This study determined the relationship between the medullary canal axis and the flexion-extension axis of the distal humerus as they relate to implant selection and design for elbow arthroplasty. Computed tomography scans of 40 fresh-frozen cadaveric specimens were analyzed with computer-aided design software. The anterior offset and cubital angle were measured between the 2 axes, and the cross-sectional area and diameter were measured for the medullary canal at various intervals.
View Article and Find Full Text PDFThis in vitro biomechanical study compared a conventional balancing technique in knee arthroplasty to a technique using computer assistance. The experimental technique used a soft tissue tensioner instrumented with computer-monitored load cells to quantify soft tissue tension. To assess outcome, a tibial load transducer measured medial and lateral compartment forces and tibial rotation.
View Article and Find Full Text PDFThe objective of this study was to determine the effect of suture repair of type 1 coronoid fractures on elbow kinematics in ligamentously intact and medial collateral ligament (MCL)-deficient elbows. Cadaveric testing was performed in stable and MCL-deficient elbows with radial head arthroplasty and with the coronoid intact, with the coronoid fractured, and after suture repair. Ulna versus humerus angulation was measured during active motion.
View Article and Find Full Text PDFSingle-strand elbow medial collateral ligament reconstruction strength was evaluated by use of double-docking and interference screw methods with either a palmaris longus tendon or GraftJacket as the reconstruction material. Thirteen upper extremities were mounted in 90 degrees of valgus orientation and subjected to cyclic valgus loading that increased progressively until failure occurred. The double-docking reconstructions outperformed the interference screw reconstructions (P < .
View Article and Find Full Text PDFJ Shoulder Elbow Surg
September 2007
The purpose of this study was to describe the extramedullary humeral morphology in paired humeri to determine whether geometric differences exist from side to side in the same individual. The anatomic characteristics of 28 paired, dry cadaveric humeri were measured by use of an electromagnetic tracking system. Of the characteristics examined, only the humeral head height was significantly different between right and left humeri in the same individual (P < .
View Article and Find Full Text PDFThe purposes of this study were to compare the initial repair strength of the medial collateral ligament (MCL) of the elbow using trans-osseous sutures and suture anchor methods and to determine the effect of repair pretensioning. Twelve, fresh-frozen upper extremities (66 +/- 5 years) were mounted in a valgus-loading system. MCL repairs were performed using trans-osseous suture and suture anchor methods with 20 N or 40 N pretensioning.
View Article and Find Full Text PDFA computer-assisted technique was developed for treatment of 4-part proximal humeral fractures via a hemiarthroplasty and tuberosity fixation. This was compared with a standard traditional method in 7 pairs of cadaveric shoulders. The computer-assisted technique used preoperative computed tomography data and computer simulations of anatomic characteristics of the contralateral humerus.
View Article and Find Full Text PDFThe management of intra-articular distal humeral fractures remains a difficult surgical problem. Although an olecranon osteotomy provides excellent exposure for management of these fractures, a number of complications can occur after the creation and repair of the osteotomy including nonunion, malunion, hardware failure, and pain secondary to prominent hardware. In an effort to reduce the incidence of these complications, the senior authors now use contoured 3.
View Article and Find Full Text PDFCircadian rhythms regulate many aspects of plant growth, fitness and vigour. The components and detailed mechanism of circadian regulation to date have been dissected in the reference species Arabidopsis thaliana. To determine the genetic basis and range of natural allelic variation for intrinsic circadian period in the closest crop relatives, we used an accurate and high throughput data capture system to record rhythmic cotyledon movement in two immortal segregating populations of Brassica oleracea, derived from parent lines representing different crop types.
View Article and Find Full Text PDFClin Biomech (Bristol)
February 2007
Background: Coronoid fractures often occur in the setting of more complex elbow trauma. Little is known about the influence of coronoid fracture size on elbow kinematics, particularly in the setting of concomitant ligament injuries. The purpose of this study was to determine the effect of coronoid fractures on elbow kinematics and stability in ligamentously intact and medial collateral ligament deficient elbows and to determine the effect of forearm position on elbow stability in the setting of coronoid fracture.
View Article and Find Full Text PDFAn understanding of the morphology of the glenoid is important from the viewpoint of implant design and selection. This study describes the endosteal dimensions and shape of the glenoid and correlates these results with age, gender, and the presence of osteoarthritis. This study used 72 scapulae.
View Article and Find Full Text PDFBackground: Comminuted fractures of the radial head are challenging to treat with open reduction and internal fixation. Radial head arthroplasty is an alternative treatment with results that compare favorably with those reported after open reduction and internal fixation of similar fractures. The purpose of this study was to evaluate the two-year outcomes and the rate of recovery of a closely followed cohort of patients in whom an unreconstructible radial head fracture had been treated with a modular metallic prosthesis.
View Article and Find Full Text PDFTen cases of Mason type I and type II isolated radial head fractures are reported, in which an unexpected cartilaginous fragment of the capitellum trapped within the radial head fracture was identified at the time of surgery. In no case was this injury pattern identified on preoperative imaging, including computed tomography in 2 cases. Five patients did have preoperative mechanical findings with forearm rotation.
View Article and Find Full Text PDFA detailed genetic linkage map of Brassica rapa has been constructed containing 545 sequence-tagged loci covering 1287 cM, with an average mapping interval of 2.4 cM. The loci were identified using a combination of 520 RFLP and 25 PCR-based markers.
View Article and Find Full Text PDFElbow arthroscopy is now being used with greater frequency to treat arthritis and contractures. The procedure is technically demanding and the potential for injury to neurovascular structures remains a concern. Potential advantages of arthroscopic treatment include improved articular visualization and decreased postoperative pain.
View Article and Find Full Text PDFPurpose: Elbow contracture is a common and difficult problem to manage. The purpose of this study was to determine the functional outcomes of arthroscopic capsular release in the management of elbow contractures.
Methods: A total of 22 patients (14 males, 8 females; mean age, 42 years) undergoing arthroscopic contracture release were retrospectively reviewed at a minimum follow-up of 1 year (mean, 25 months).
A major component in the regulatory network controlling fruit ripening is likely to be the gene at the tomato Colorless non-ripening (Cnr) locus. The Cnr mutation results in colorless fruits with a substantial loss of cell-to-cell adhesion. The nature of the mutation and the identity of the Cnr gene were previously unknown.
View Article and Find Full Text PDFThe incorrect determination of the flexion-extension axis of the elbow may result in poor clinical outcomes for patients undergoing ligament repairs, joint arthroplasties, and procedures requiring articulated external fixators. The variability in the selection of the flexion-extension axis based on a visual approximation of bony landmarks on the distal humerus was studied within a group of surgeons. Three surgeons of different experience levels independently selected points through which they believed the flexion-extension axis passed on the medial and lateral surfaces of 23 distal humeri.
View Article and Find Full Text PDFThe surgical and therapeutic management for total elbow arthroplasty is reviewed. Surgical overview and techniques, stability issues, factors affecting therapy, and a proposed postoperative treatment plan are presented. Specific therapy management following total elbow replacement has not been published before in a peer-reviewed journal.
View Article and Find Full Text PDFBackground: Capitellar and trochlear fractures are uncommon fractures of the distal aspect of the humerus. There is limited information about the functional outcome of patients managed with open reduction and internal fixation.
Methods: The functional outcome of twenty-eight patients, with a mean age (and standard deviation) of 43 +/- 13 years, who were treated with open reduction and internal fixation for capitellar and trochlear fractures was evaluated at a mean duration of follow-up of 56 +/- 33 months.
We have investigated the copy numbers and genomic organization of five representative reverse transcriptase domains from retrotransposons in Brassica oleracea. Two non-homologous Pseudoviridae (Ty1/copia-like) elements, two Metaviridae (Ty3/gypsy-like) elements (one related to the Athila family) and one Retroposinae (LINE) element were hybridized to a gridded BAC library, "BoB". The results indicated that the individual LTR retrotransposons (copia and gypsy-like) were represented by between 90 and 320 copies in the haploid genome, with only evidence of a single location for the LINE.
View Article and Find Full Text PDFTotal elbow arthroplasty remains the most definitive functional procedure for patients with end-stage painful arthritis of the elbow. Complication rates have historically been quite high, and early revision was not uncommon. A greater understanding of elbow anatomy and kinematics has led to advances in prosthetic design and surgical technique.
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