Flexion strength of the toes in the normal foot. An evaluation using magnetic resonance imaging.

Flexion of the toes may be active from muscle contraction or passive from the reversed windlass function of the plantar aponeurosis. The aim of this study was to estimate the flexion moments the muscles of the foot and long digital flexors may be capable of generating and compare these calculations with published data. Magnetic resonance images were used to measure the maximal cross-sectional area of the foot muscles and long digital flexors, along with the radius of curvature of the metatarsal heads. Using known physiological data the maximal flexion moments the muscles may be able to generate at the metatarsophalangeal (MTP) joints were calculated. The methodology overestimates muscle strength and flexion moments at the metatarsophalangeal joints. The calculated maximal flexion moment at the 1st MTP joint is 4.27-6.84 Nm, for the 2nd, 3rd and 4th MTP joints 3.06-4.91 Nm, and the 5th MTP joint 0.47-0.75 Nm. The flexion moments the muscles may generate at the MTP joints do not account for the flexion forces seen in normal walking. Given that maximal strength is not used in normal walking, we conclude that the reversed windlass mechanism of the plantar aponeurosis must be important in normal function of the toes.

Metatarsal extension osteotomy without plantar aponeurosis release in cavus feet. The effect on claw toe deformity a radiographic assessment.

BACKGROUND: This study reviewed patients undergoing correction of cavus foot deformity by metatarsal extension osteotomy with preservation of the plantar aponeurosis, and assessed the correction achieved of the claw deformity of the toe by radiographic assessment. METHOD: 15 patients (18 feet) were reviewed clinically and radiographically. All feet required extension osteotomy of the first metatarsal and four patients (5 feet) had extension osteotomy of the first to fourth metatarsals. Hallux extension angle in relation to the 1st metatarsal and in relation to the ground was measured in all feet to estimate the degree of clawing of the hallux. RESULTS: 13 patients (15 feet) were satisfied with the outcome of their surgery and also the appearance of their foot. The mean radiographic change in the hallux extension angle in relation to the 1st metatarsal was 16°, and in relation to the ground was 7°. These changes were statistically significant. CONCLUSION: Our results indicate an improvement in the claw toe deformity and we recommend preservation of the plantar aponeurosis in corrective surgery for cavus foot.

Instability of the tibio-fibular syndesmosis: have we been pulling in the wrong direction?

Syndesmotic stability in ankle fractures is usually assessed intraoperatively by pulling on the fibula with a bone hook in the coronal plane ("Hook Test"). Our clinical observations have suggested that instability may be more marked in the sagittal plane. Our aim was to compare movement at the tibio-fibular syndesmosis in the sagittal and coronal planes after sequential ligament division in a cadaver model. Seven specimens were used. The Hook Test was performed in both the sagittal and coronal planes. Movement was assessed by measuring the displacement of parallel k-wires. In all specimens, the anterior tibio-fibular, interosseous and posterior tibio-fibular ligaments were sequentially divided. In three specimens the deltoid ligament was then divided and the interosseous membrane in another three. After division of all three syndesmosis ligaments the mean displacement was 8.8 mm (+/-3.9) in the sagittal plane and 1.5 mm (+/-0.4) in the coronal plane. When the deltoid ligament was then divided, the displacement increased to 11.7 mm (+/-2.4) and 3.2 mm (+/-0.5), respectively. When the interosseous membrane was divided the measurements were 12.7 mm (+/-4) and 3.1 mm (+/-1.5). Movements were consistently greater in the sagittal plane than the coronal plane and we conclude that distal tibio-fibular instability should be assessed in the sagittal plane.

Ongoing developments in CCP4 for high-throughput structure determination.

Collaborative Computational Project Number 4 (CCP4) was established in 1979 to promote collaboration between UK groups writing software for protein crystallography. From these beginnings, CCP4 now distributes a large software suite and is active in developing new software. In this article, an overview is given of recent and ongoing developments in the CCP4 software suite, in particular as they pertain to high-throughput studies. Developments in individual programs are discussed first, although these are covered in more detail elsewhere. The bulk of the article focuses on the infrastructure of the software suite which allows the user to move effortlessly between different programs or to create automated schemas. Major changes to the software library at the heart of the CCP4 suite, developments in the CCP4 graphical user interface, and data management within CCP4 are discussed. The latter is crucial to high-throughput studies, where a large number of data are imported, created and finally archived.

The new Northwestern Memorial Hospital: planned, constructed, and operated through the patients first philosophy.

BACKGROUND: On May 1, 1999, Northwestern Memorial Hospital, after ten years of planning and construction, opened a 2 million-square-foot replacement hospital and ambulatory care center designed to deliver patient-centered care well into the 21st century. SEEKING INPUT FOR THE BUILDING DESIGN: More than 1000 persons, including physicians, patients and families, volunteers, board members, neighborhood residents, and employees, made up the 125 functional user groups that assessed every aspect of the building plan, from structural configuration and space usage to signage and control of infectious disease. Senior management developed guiding assumptions and objectives for the replacement facility: Promote patient convenience and comfort; support staff and improve service/operational efficiencies; eliminate duplication of costly technologies; introduce leading-edge innovations in infection control, information technology, communications, and other areas; and provide flexibility for future technologies and growth. OUTCOMES: The new building has accomplished its core goals. Patients receive all their medical care without leaving the facility. Inpatient and outpatient services have been separated to provide enhanced privacy, greater comfort, and efficiency for all patients. EPILOGUE: The $580 million project was completed on time and on budget. The physical move of patients on this date occurred smoothly and quickly, with no patient care or employee safety problems. Most of the unexpected problems were minor and easily rectified. During the first six weeks, key management team members met daily to debrief on new issues identified and old ones resolved, and issued e-mail bulletins to highlight improvements and solicit feedback and other ideas.

Surgical management of acute tarsometatarsal fracture dislocation in the adult.

Injuries to the tarsometatarsal joint involving fracture dislocations are uncommon and are often referred to as Lisfranc lesions after the French field surgeon in the Napoleonic Wars. Despite the infrequency of this serious injury, they have the potential for chronic disability and require prompt, accurate diagnosis and precise anatomic reduction to minimize long term disability. A review of the literature shows that opinions differ as to the most appropriate method of treatment for these injuries, be it closed or open reduction, but most authors agree that it is imperative to achieve precise anatomic reduction.

Actions of endothelin-1, 2, and 3 in the microvasculature of bone.

Endothelins have recently been associated with hypoxia-related vascular smooth-muscle constriction and with the so-called no-reflow phenomenon following reperfusion. Their action is tissue dependent. The role of endothelins on vascular smooth muscle in bone is unknown. An ex vivo perfusion model was used to investigate the effects of the three different endothelins on the vascular resistance in the canine tibia. Endothelin-1 and endothelin-2 had molar potencies similar to that of norepinephrine, whereas endothelin-3 was less potent. Tachyphylaxis to the same dose of endothelin-1 did not occur. The calcium channel blocker, diltiazem, attenuated (45% reduction) the vasoconstrictor responses to norepinephrine (p < 0.005) but had a smaller effect (24% reduction) on the responses to endothelin (p < 0.025). Vascular smooth muscle in bone appears to have endothelin receptors that are similar to those in other organs.

Blood utilization in hip and knee arthroplasty: a cost-minimization study.

The non-utilization of crossmatched blood is an expensive waste of resources. We have audited blood utilization for all primary total hip and knee arthroplasty patients. We compared routine pre-operative crossmatching (Phase 1) with a policy of group, screen and save (G & S) only (Phase 2). The patient groups were similar in both phases. Pre- and post-operative haemoglobin results were not significantly different between Phase 1 and 2. No adverse transfusion reactions occurred. In Phase 1, 213 units were crossmatched pre-operatively, but only 127 (60%) were transfused. In Phase 2, 117 units were requested and all transfused. The G & S only policy proved to be a safe and practical option which improved the efficiency and cost-effectiveness of blood ordering. Based on a handling charge of 37.50 Pounds per unit of blood by the Regional Transfusion Centre, an estimated annual saving of over 8000 Pounds can be made in our directorate.

Glove perforation during hip arthroplasty. A randomised prospective study of a new taperpoint needle.

Exposure to blood is a hazard for all surgeons. We assessed the incidence of glove perforation and needlestick injury from a new blunt taperpoint needle designed to penetrate tissues other than skin with the minimum of force. We performed a prospective, randomised trial comparing the incidence of perforations of surgical gloves with the new needle and a standard cutting needle during wound closure after hip arthroplasties. There was at least one glove perforation in 46 of 69 such procedures (67%). The use of the taperpoint needle produced a significant decrease in perforations (p = 0.049).

Closed extensor tendon rupture and distal radial fracture with use of a gymnast's wrist support.

We report a case of delayed closed rupture of the tendon of extensor indicis proprius in a skeletally immature individual. This occurred following a minor greenstick fracture during use of a gymnast's wrist-finger support. To our knowledge this unusual complication has not been described previously.

Radiographic assessment of component orientation in elbow arthroplasty. A technical description.

We describe an alternative method of taking standardized radiographs of the elbow in patients with rheumatoid arthritis, taking into account fixed deformities. The technique enables assessment of the orientation of joint replacement components, including their axial rotational alignment. The accuracy of the method for calculating axial rotational alignment has been evaluated using a skeleton model. Within the 20 degrees limits of arm position the accuracy was found to be on average 1.4 degrees for the humerus and 2.2 degrees for the ulna.

Supracondylar fractures of the humerus in childhood: range of movement following the posterior approach to open reduction.

The posterior approach for open reduction of supracondylar fractures of the humerus has been condemned for causing decreased elbow movement. This study investigates this by comparing the range of movement in children treated by posterior open reduction and Kirschner wiring with those treated by closed reduction and immobilization. A total of 65 children with severely displaced supracondylar humeral fractures have been reviewed. There was some loss of movement in 66 per cent of the open reduction group and 42 per cent of the closed reduction group. The proportion losing more than 10 degrees of movement was the same in both groups. The difference between the two groups was due to the increased numbers in the open reduction group who lost less than 10 degrees of motion. Posterior open reduction of childhood supracondylar fractures is not associated with an important loss of elbow movement and need not be avoided on this account.

Computer-unaided diagnosis of acute abdominal pain in an accident and emergency department.

The initial accident and emergency and final in-patient diagnoses of 200 patients with acute abdominal pain made without computer aid or structured data sheet were compared. Sixty-five per cent were correctly diagnosed and 5% had normal laparotomies. These results compare favourably with those obtained using computer aid and structured history-taking forms. It is suggested that the spotlight should be on the training and experience of doctors making the initial diagnosis rather than on computer aid.