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1.
Phys Rev Lett ; 127(3): 033001, 2021 Jul 16.
Article in English | MEDLINE | ID: mdl-34328758

ABSTRACT

Isotope shifts of ^{223-226,228}Ra^{19}F were measured for different vibrational levels in the electronic transition A^{2}Π_{1/2}←X^{2}Σ^{+}. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the electronic density within the radium nucleus. Ab initio quantum chemical calculations are in excellent agreement with experimental observations. These results highlight some of the unique opportunities that short-lived molecules could offer in nuclear structure and in fundamental symmetry studies.

2.
Hand Surg Rehabil ; 40(5): 622-630, 2021 10.
Article in English | MEDLINE | ID: mdl-33933635

ABSTRACT

Intramedullary screw (IMS) fixation is increasingly used as an alternative treatment option in metacarpal and phalangeal fractures of the hand. However, this technique is currently the subject of controversy among hand surgeons. The aim of this systematic review was to gain insight on radiological, functional and patient-rated outcomes reported in literature. A comprehensive literature search of PubMed, Embase, CENTRAL and CINAHL databases was conducted on March 1st, 2021. All studies reporting on fracture union, complications, and functional and patient-rated outcome in IMS fixation of metacarpal and/or phalangeal fractures were selected. Two prospective and 16 retrospective cohort studies were included, encompassing a total of 837 patients with 958 fractures (693 metacarpal, 222 proximal phalangeal and 43 middle phalangeal). Mean surgery duration was 26.4 min (range 5-60 min). Union was ultimately achieved in all fractures in a mean of 5.7 weeks (range 2-12 weeks). The procedure-related complication rate was 3.2%. The most frequently reported complication was limitation of joint motion, occurring in 2.0% of cases. Incidence of other complications, including loss of reduction, infection and screw protrusion did not exceed 1%. Overall mean total active motion averaged 243° and grip strength reached 97.5% of the contralateral side. The Disabilities of the Arm, Shoulder and Hand (DASH) score averaged 3.7 points. Duration of sick leave was 7.3 weeks. According to the findings of this systematic review, IMS fixation is a time-saving and safe minimally invasive solution for both metacarpal and phalangeal fractures, with a low rate of complications and promising functional and patient-rated results.


Subject(s)
Metacarpal Bones , Bone Screws , Fracture Fixation, Internal/methods , Humans , Metacarpal Bones/surgery , Prospective Studies , Retrospective Studies , Upper Extremity
3.
Nature ; 581(7809): 396-400, 2020 05.
Article in English | MEDLINE | ID: mdl-32461650

ABSTRACT

Molecular spectroscopy offers opportunities for the exploration of the fundamental laws of nature and the search for new particle physics beyond the standard model1-4. Radioactive molecules-in which one or more of the atoms possesses a radioactive nucleus-can contain heavy and deformed nuclei, offering high sensitivity for investigating parity- and time-reversal-violation effects5,6. Radium monofluoride, RaF, is of particular interest because it is predicted to have an electronic structure appropriate for laser cooling6, thus paving the way for its use in high-precision spectroscopic studies. Furthermore, the effects of symmetry-violating nuclear moments are strongly enhanced5,7-9 in molecules containing octupole-deformed radium isotopes10,11. However, the study of RaF has been impeded by the lack of stable isotopes of radium. Here we present an experimental approach to studying short-lived radioactive molecules, which allows us to measure molecules with lifetimes of just tens of milliseconds. Energetically low-lying electronic states were measured for different isotopically pure RaF molecules using collinear resonance ionisation at the ISOLDE ion-beam facility at CERN. Our results provide evidence of the existence of a suitable laser-cooling scheme for these molecules and represent a key step towards high-precision studies in these systems. Our findings will enable further studies of short-lived radioactive molecules for fundamental physics research.

4.
Hand Surg Rehabil ; 39(3): 186-192, 2020 05.
Article in English | MEDLINE | ID: mdl-32126291

ABSTRACT

Arthroplasty of the distal radioulnar joint (DRUJ) using a semiconstrained DRUJ implant yields good outcomes according to the literature. The aim of this study was to investigate the subjective, clinical and radiographic outcomes with a special focus on complications in nine patients with a mean follow-up of 6years and to compare them with our previously published 3-year follow-up results. No subjective or objective changes were seen between the 3-year and the 6-year follow-up. In the previous study, one implant loosening and two irritations of the superficial branch of the radial nerve occurred. We saw three complications that needed surgery in addition to the three complications already found 3years after surgery. One patient with a large ulna had loosening of the cemented ulnar stem and therefore the prosthesis was explanted. One patient had an allergic reaction to the metal alloy of the prosthesis, which also led to removal. One patient had an ulnar impaction syndrome caused by too-distal placement of the implant that needed revision. Prior studies reported low complication rates. In our study, six complications occurred in four out of nine patients, requiring reoperation including two revisions and two implant removals. A precise surgical technique is mandatory to avoid the otherwise frequent complications and potential implant failures. LEVEL OF EVIDENCE: IV.

5.
Hand Surg Rehabil ; 37(2): 99-103, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29503183

ABSTRACT

We analyzed the results of 20 unstable metacarpal fractures in 15 patients treated with a cannulated compression screw and no immobilization. All fractures healed within 6 weeks. One patient with multiple fractures and a flexion deficit required arthrolysis of two metacarpophalangeal joints. Another patient had an extension lag. There were no other complications. This fast and easy technique results in good outcomes for unstable metacarpal fractures. The advantages are early active motion without immobilization and stable fixation. Surgical removal of the screw is rarely needed. LEVEL OF EVIDENCE: IV (therapeutic).


Subject(s)
Bone Screws , Fracture Fixation, Internal/instrumentation , Fractures, Bone/surgery , Metacarpal Bones/surgery , Adult , Aged , Fracture Fixation, Internal/methods , Fracture Healing , Hand Strength , Humans , Male , Metacarpal Bones/injuries , Middle Aged , Operative Time , Physical Therapy Modalities , Postoperative Care , Young Adult
7.
Hand Surg Rehabil ; 36(3): 192-197, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28465206

ABSTRACT

We present the results of a prospective study of 31 thumbs in 30 patients affected by primary osteoarthritis at the thumb carpometacarpal (CMC1) joint who were treated with denervation of the involved joint. For every operated hand, the Kapandji score, key-pinch strength, grip strength and pain on a visual analogue scale were evaluated preoperatively and postoperatively at 2 weeks, 6 weeks, 3 months, 6 months and 1 year. The patients' satisfaction was determined. The Kapandji score and key-pinch strength improved significantly in all patients. Grip strength improved significantly in 10 hands. Pain was reduced in all cases. Nevertheless, 6 patients were dissatisfied with the operation. Of these 6 patients, 4 had stage IV arthritis in the TMC and scaphotrapeziotrapezoid joints of the thumb. Thumb CMC denervation appears to reduce pain at 1 year with an overall improvement in key-pinch strength. However, patients with stage IV CMC arthritis were not satisfied with the outcome of the procedure.


Subject(s)
Carpometacarpal Joints/surgery , Denervation , Osteoarthritis/surgery , Thumb/surgery , Adult , Aged , Aged, 80 and over , Carpometacarpal Joints/innervation , Female , Hand Strength , Humans , Male , Middle Aged , Osteoarthritis/classification , Patient Satisfaction , Prospective Studies , Thumb/innervation , Visual Analog Scale
8.
J Wrist Surg ; 5(4): 290-296, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27777820

ABSTRACT

Range of motion and stability are important outcome parameters to assess function of the distal radioulnar joint (DRUJ), in particular pronation, supination, and weight-lifting capacity. The DRUJ semiconstrained implant developed by Scheker et al is intended to reproduce all the functions of the triangular fibrocartilage complex and the DRUJ. The aim of the study was to investigate the subjective, clinical, and radiographic results in 10 patients after primary implantation of the semiconstrained DRUJ arthroplasty following DRUJ derangement and painful instability, with an average follow-up of 3 years with a special focus on the complications. Standardized preoperative and postoperative evaluation included assessment of pain by a visual analog scale, radiographic examination, range of motion measurements, lifting capacity, and grip strength. The patient-perceived function was investigated using clinical score charts. Compared with the preoperative status, range of motion showed little change, while grip strength, lifting capacity, pain score, and patient-perceived functions improved significantly. One patient developed an ulna stem loosening, while two patients had to be reoperated because of an irritation of the extensor tendons and the superficial radial nerve at the first dorsal compartment of the wrist. In this study, arthroplasty of the DRUJ using the semiconstrained DRUJ arthroplasty was found to result in satisfactory outcome. Level of evidence: Level IV.

9.
Hand Surg Rehabil ; 35(5): 307-319, 2016 10.
Article in English | MEDLINE | ID: mdl-27781975

ABSTRACT

Skin coverage in hand reconstruction is a challenging and vast chapter in hand surgery; covering every aspect of it in a report is simply not feasible. Therefore, this report focuses on a few specific topics. The coverage of anatomical regions like the fingertips is common ground for hand surgeons worldwide, but in the last 10 years, various refinements have been published in order to optimize the reconstruction of this organ. Nevertheless, in many emergency departments, the amputation of badly injured fingertips, including the thumb, remains the preferred treatment. The main focus of this report is to counter this tendency by providing alternatives to surgeons. Large defects in the fingers involving more than one segment, defects in the palm and in the dorsum of the hand are currently debated in international meetings. The use of skin substitutes vs. the use of extremely refined microsurgical procedures vs. classic island flaps has generated animated discussions, which are also influenced by cultural and socioeconomic factors around the world. This report offers the views of six surgeons from four different countries, in the hope of animating discussions and suggesting new approaches.


Subject(s)
Advisory Committees , Conservative Treatment/methods , Dermatologic Surgical Procedures/methods , Fingers/surgery , Surgical Flaps , Hand/surgery , Humans , Plastic Surgery Procedures/methods , Thumb , Treatment Outcome
10.
Hand Surg Rehabil ; 35(5): 335-340, 2016 10.
Article in English | MEDLINE | ID: mdl-27781978

ABSTRACT

Fifteen consecutive patients with severely comminuted Rolando fractures were treated by closed reduction and fixation with a modified Suzuki frame without rubber bands, followed by immediate mobilization. All the fractures healed within 5 weeks. At 3 months, no rotational deformity was observed. The Kapandji score was equal that of the contralateral thumb in eight cases. No residual pain was recorded. Grip strength was 78% and pinch strength was 78% of the contralateral hand. One patient needed the frame tension modified. One patient developed a sensory deficit in the area of the superficial branch of the radial nerve that resolved spontaneously in 3 months. One patient healed with a 2-mm articular step-off, but the clinical outcome was good. Our retrospective study suggests that the small modification we made to the Suzuki frame provides a relatively simple and minimally invasive technique for the treatment of comminuted Rolando fractures.


Subject(s)
Fracture Fixation/instrumentation , Fractures, Comminuted/surgery , Intra-Articular Fractures/surgery , Metacarpal Bones/injuries , Thumb/injuries , Adolescent , Adult , Aged , Aged, 80 and over , Equipment Design , Female , Fracture Fixation/methods , Hand Strength , Humans , Male , Middle Aged , Radiography , Range of Motion, Articular , Retrospective Studies , Young Adult
11.
J Hand Surg Eur Vol ; 41(7): 688-94, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27056277

ABSTRACT

UNLABELLED: We present the results of 26 patients with 31 consecutive displaced or unstable extra-articular fractures of the base and shaft of the proximal and middle phalanges of the digits of the hand, treated over a period of 12 months with an intramedullary headless compression screw and early mobilization with no splinting. All fractures healed with no major complications. Only one patient, who had a pathological fracture through an enchondroma, required a tenolysis to improve the mobility of the finger. This technique seems to be technically simple, effective and with few drawbacks. LEVEL OF EVIDENCE: IV.


Subject(s)
Bone Screws , Finger Phalanges/injuries , Fracture Fixation, Intramedullary/instrumentation , Fractures, Bone/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Cohort Studies , Early Ambulation , Female , Humans , Male , Middle Aged , Treatment Outcome , Young Adult
12.
J Hand Surg Eur Vol ; 41(7): 683-7, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27056278

ABSTRACT

The aim of this study was to quantify the articular cartilage defect created with two different antegrade techniques of intramedullary osteosynthesis with a headless compression screw inserted through the metacarpophalangeal joint. In 12 out of 24 fingers from six cadaveric hands, a trans-articular technique with cannulated headless compression screws (2.2 and 3.0 mm diameter) was used; whereas in the other 12 fingers, an intra-articular fixation technique was used. The areas of the articular surface and the defects created were measured with a digital image software program. All measurements were made twice by two observers. In the intra-articular technique, the average defect in the base of the articular surface of the proximal phalanx was 4.6% with the 2.2 mm headless compression screw and 8.5% with the 3.0 mm screw. In the trans-articular technique, the defect size was slightly smaller; 4.2% with the 2.2 mm screw and 8% with the 3.0 mm screw, but the differences were not statistically significant. The main advantage of the intra-articular technique was that it avoided damage to the articular surface of the metacarpal head.


Subject(s)
Bone Screws , Finger Phalanges/injuries , Fracture Fixation, Internal/instrumentation , Fractures, Bone/surgery , Aged , Aged, 80 and over , Cadaver , Female , Fractures, Bone/pathology , Humans , Male , Metacarpophalangeal Joint/pathology , Metacarpophalangeal Joint/surgery
13.
J Plast Reconstr Aesthet Surg ; 69(8): 1017-23, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26947671

ABSTRACT

BACKGROUND: Population aging strongly affects the demographic development of industrialized countries. While microsurgical procedures were initially believed to be only feasible in patients of younger age because of the duration of the surgical procedure and the higher risk of vascular insufficiency due to age-related comorbidities, it has become evident that these procedures are beneficial even for patients at an advanced age. METHODS: We retrospectively investigated microsurgical procedures in a patient cohort (n = 25 with 27 free flaps) with a minimum age of 78 years with regard to patients' characteristics, flap survival, and postoperative surgical and medical complications. RESULTS: Median age was 81 years (IQR 6). Most defects were located in the head and neck region. The mean operation time was 384 min (standard deviation (SD) 131). Flap failure was observed in three cases (11%). The median length of hospital stay was 17 days (interquartile range (IQR) 8). The mean ASA score was 2.48. Patients' age and ASA group did not correlate. The mortality rate was 4%. Postoperative surgical complications were observed in 11 cases (41%), while 19 patients (70%) showed one or more medical complications. Higher ASA classes tended to show more postoperative complications. However, neither age nor operating time nor ASA status showed significant influence on the occurrence of postoperative medical or surgical complications. CONCLUSION: There is growing demand for structural and functional restoration using free tissue transfer in an aging population. If there are no alternative treatment options available promising similar structural and functional preservation, free tissue transfer is justifiably in very old patients despite a potentially increased flap failure. As such, free tissue transfer is used as a curative treatment concept aiming at a maximum of patients' independence and early ambulation. Occurrence of complications can be diminished by adequate patient selection and thorough perioperative care.


Subject(s)
Head and Neck Neoplasms/surgery , Microsurgery , Plastic Surgery Procedures , Age Factors , Aged , Aged, 80 and over , Female , Head and Neck Neoplasms/complications , Head and Neck Neoplasms/pathology , Humans , Male , Operative Time , Retrospective Studies , Surgical Flaps , Treatment Outcome
14.
Chir Main ; 34(5): 240-4, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26404796

ABSTRACT

Digital replantation is a well-established and increasingly common procedure in specialized hand surgery units worldwide. Replantation after complex trauma is often challenging due to severely injured, small-diameter vessels, especially at the distal level. Digit salvage by arteriovenous anastomosis has been inadequately described in the literature for such cases. The objective of this study was to evaluate the outcomes and complications of arteriovenous digital replantation in complex amputations. We reviewed five cases of digital replantation using a single palmar afferent arteriovenous anastomosis and drainage via a dorsal vein. The postoperative protocol followed our standard replantation protocol. All digits survived with no revision procedures. No major complications were observed. One digit developed partial epidermolysis and one thumb developed marginal skin necrosis, both treated conservatively. The color of the replanted digits was not a reliable monitoring parameter but capillary refill was consistently visible. Microangiography performed four months after surgery demonstrated good digit perfusion. Our results support palmar arteriovenous anastomosis as a reliable alternative in digital replantation if distal arteries are unavailable for anastomosis. The results also suggest that this digit salvage procedure can be carried out at a more proximal level than previously reported.


Subject(s)
Amputation, Traumatic/surgery , Arteriovenous Anastomosis , Finger Injuries/surgery , Replantation/methods , Adult , Aged , Aged, 80 and over , Humans , Middle Aged
16.
J Hand Surg Eur Vol ; 39(5): 520-5, 2014 Jun.
Article in English | MEDLINE | ID: mdl-23877728

ABSTRACT

This article presents a technique for facilitating use of pinch between the ring and little fingers for use in rare cases of congenital absence, or severe hypoplasia, of the thumb in which pollicization of the index finger is impossible, or not advised because the child is already pinching by scissor action between the ring and little fingers. The technique avoids drawing attention to the hand, as is the case after true pollicization of the little finger. The technique was used in five hands in five children. Three of the patients could only be followed for under 2 years. Two patients were available for longer follow-up of 6 years and 2 months and 3 years after surgery. The surgery was shown to facilitate opening of the web and pinch between the little and ring finger tips, and continues to be of functional value to the children as they grow.


Subject(s)
Fingers/surgery , Orthopedic Procedures/methods , Thumb/abnormalities , Child, Preschool , Hand Deformities, Congenital/physiopathology , Hand Deformities, Congenital/surgery , Humans , Pinch Strength , Recovery of Function , Thumb/pathology
17.
Indian J Plast Surg ; 46(2): 312-24, 2013 May.
Article in English | MEDLINE | ID: mdl-24501468

ABSTRACT

This review describes the biological problems faced by those managing primary flexor tendon injuries and explains why these problems still thwart attempts to achieve normal, or near normal, function after this injury, despite a century of surgical effort. It considers the historical background of the early 20(th) century attempts to improve the results and analyses the clinical usefulness of more recent research into tendon core and circumferential suture modification, including the authors' work in this field, and changes in post-operative mobilisation over the last 50 years. More recent manipulation of the sheath to improve results and the future possibility of manipulation of adhesions are discussed. It also discusses other factors, e.g., the patient, the experience of the surgeon, the use of therapists, the timing of repair, complex injuries, injuries in zones other than zone 2, which can have a bearing on the results and considers how these can be modified to avoid an unfavourable outcome.

19.
J Hand Surg Am ; 37(6): 1200-7, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22624784

ABSTRACT

PURPOSE: The aims of this anatomical study were to identify any extrinsic blood supply to the median nerve in the distal forearm and to measure the tension required to approximate the severed nerve after and before dissecting it while maintaining its extrinsic blood supply. METHODS: We injected the arterial system of 15 lightly embalmed forearms with red latex to define the vascular anatomy of the median nerve in the distal forearm. We measured the gap resulting from spontaneous retraction of the cut ends of the divided median nerve and the average tension needed to reapproximate the ends before and after resection of the attachments to the nerve on its superficial, deep, and ulnar aspects. RESULTS: A constant branch to the median nerve arises from the radial artery approximately 5 cm proximal to the radial styloid process. The mean gap between the severed nerve ends was 1.2 cm (range, 0.9-1.7 cm). The mean tension required to coapt the nerve ends was 231 g force (range, 200-280 g), reducing to 89 g force (range, 60-110 g) when only its radial attachments, including this vessel, were preserved. CONCLUSIONS: This cadaveric study suggests that it may be possible to advance the median nerve at the wrist while retaining the vascular connection and blood supply from the radial artery, and so maintain the vascularity of the nerve at the common site of nerve repair in the distal forearm. CLINICAL RELEVANCE: This cadaveric study identifies constant arterial feeding branches from the radial artery to the median nerve in the distal forearm, and is a preliminary investigation into the possibility of advancing the median nerve for repair in the distal forearm while maintaining the continuity of this branch.


Subject(s)
Forearm/blood supply , Forearm/innervation , Median Nerve/blood supply , Adult , Aged , Aged, 80 and over , Cadaver , Female , Humans , Male , Middle Aged
20.
Rev Sci Instrum ; 82(6): 063105, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21721672

ABSTRACT

We present a continuous-wave optical parametric oscillator (OPO) capable of high resolution spectroscopy at wavelengths between 4.8 µm and 5.4 µm. It is based on periodically poled lithium niobate (PPLN) and is singly resonant for the signal radiation around 1.35 µm. Because of the strong absorption of PPLN at wavelengths longer than 4.5 µm, the OPO threshold rises to the scale of several watts, while it produces idler powers of more than 1 mW and offers continuous tuning over 15 GHz. A supersonic jet spectrometer is used in combination with the OPO to perform measurements of the transient linear molecule Si(2)C(3) at 1968.2 cm(-1). Fifty rovibrational transition frequencies of the ν(3) antisymmetric stretching mode have been determined with an accuracy on the order of 10(-4) cm(-1), and molecular parameters for the ground and the v(3) = 1 state have been determined most precisely.

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