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Stock assessors commonly use models that incorporate biological data such as fish length and age to determine the status of fish stocks and how different management scenarios affect stock size. Ages used in assessment models need to be accurate and precise because ageing error can affect many model inputs and potentially result in stock mismanagement. Despite the requirement for sound age data, few studies have investigated accuracy of ages for groundfish captured in coastal nearshore waters off Oregon, USA. In this study, we validate otolith ages for Black Rockfish (Sebastes melanops), Copper Rockfish (Sebastes caurinus) and Cabezon (Scorpaenichthys marmoratus), three species with recreational and commercial importance to Oregon. Ages obtained by traditional break-and-burn methods were validated using secondary ion mass spectrometry (SIMS) to examine otolith stable oxygen isotope ratios (δ18O) over a fish’s lifetime. This technique relies on the inverse relationship that exists between otolith δ18O and ambient water temperature, and independent counts of δ18O maxima should be comparable to ages obtained by visual counts of otolith growth marks laid down during cold water periods. Locations of δ18O maxima in otolith chronologies matched well with locations of visual growth marks in otoliths of all three species, maxima counts were strongly positively correlated with age, and variation in otolith δ18O decreased with age. However, significant variability in the δ18O chronologies caused by variability in intra-seasonal upwelling and resulting water temperature variations made maxima counts difficult in several samples. Correct interpretation of chronologies required knowledge of location of the first annulus, the compression of growth zones with age, and an assumption of the seasonal amplitude of the ambient water δ18O.

The South Mountain Batholith (SMB; Nova Scotia, Canada) is the largest composite batholith exposed in the Appalachians and lies entirely within the most outboard Meguma terrane. In situ and CA–TIMS U–Pb dating and in situ isotopes (Lu–Hf, O) and geochemistry for zircon from all phases of the SMB constrain its source as well as its evolution. CA–ID–TIMS for zircon yields emplacement (autocryst) ages, indicating a transition from granodiorite (378.7 ± 1.2 to 375.4 ± 0.8 Ma) to leucogranite (375.4 to 371.8 ± 0.8 Ma) over several million years. Furthermore, in situ SHRIMP, LA–MC–ICP–MS, and SIMS analyses of distinct zircon domains reveal: (1) abundant ancient xenocrysts (∼420 Ma to 2.2 Ga); (2) antecryst ages ca. 3–15 million years older than SMB emplacement; (3) autocryst δ18O values between +7.3‰ and +9.1‰ (V-SMOW); (4) similar isotopes, REE signatures, and derived fO2 values among antecrysts and autocrysts; and (5) εHf values from the 371.8 ± 0.8 Ma Davis Lake Pluton (DLP) autocrysts that are higher (+1.74 to +4.38) than the rest of the SMB (−2.99 to +1.68). Collectively, these data suggest a protracted magmatic evolution for the SMB with melt generation and assembly from ∼390 to 370 Ma via melting of a metasomatized mantle source followed by contamination, first from the structurally underlying Avalonian terrane and later by metasedimentary wall rocks of the Meguma terrane. The most southwesterly part of the SMB (i.e., DLP) represents a petrogenetically distinct magmatic phase that underwent less overall contamination than the rest of the SMB.

We developed an accelerated Genetic Algorithm (GA) system based on the cooperation of a field-programmable gate array (FPGA) and the optimized parameters that enables fast light focusing through scattering media. Starting at the searching space, which influences the convergence of the optimization algorithms, we manipulated the mutation rate that defines the number of mutated pixels on the spatial light modulator to accelerate the GA process. We found that the enhanced decay ratio of the mutation rate leads to a much faster convergence of the GA. A convergence-efficiency function was defined to gauge the tradeoff between the processing time and the enhancement of the focal spot. This function allowed us to adopt the shorter iteration number of the GA that still achieves applicable light focusing. Furthermore, the accelerated GA configuration was programmed in FPGA to boost processing speed at the hardware level. It shows the ability to focus light through scattering media within a few seconds, 150 times faster than the PC-based GA. The processing cycle could be further promoted to a millisecond-level with the advanced FPGA processor chips. This study makes the evolution-based optimization approach adaptable in dynamic scattering media, showing the capability to tackle wavefront shaping in biological material.

Introduction: Transfemoral amputation results in a prosthesis which bears weight on the ischium. Gait disturbance, lack of an end-bearing stump and discomfort in the groin from the socket even while sitting, are important issues. Methods: This is a pilot report of an ongoing randomized blind clinical trial of a new intramedullary implant post transfemoral amputation. Here, we describe a single case illustrating the surgical technique and clinical outcome of a dysfunctional post-traumatic transfemoral amputation addressed with this implant. Clinical gait analysis, SF-12 and VAS were assessed pre- and post-intervention at 6 months of follow-up. Results: An improved stump control is accomplished by means of myoplasty and myodesis through an end-cap. Stride width improved from 0.21 m pre-op to 0.13 m post-op, and more symmetrical stride length (△0.21 m pre-op vs. △0.06 m post-op) was noted, indicating improved gait quality and stability. Gait velocity increased (0.51 ± 0.04 m/s pre-op vs. 0.64 ± 0.02 m/s post-op). Conclusion: This technique reveals improvements in gait parameters in a transfemoral amputee treated with a new procedure. Improved prosthesis control, sitting comfort, greater hip range of motion, better gait stability, and enhanced walking abilities were noted.

Background: Little is known about the rate and reasons for revision after primary Metatarsophalangeal (MTP1) arthrodesis with the latest implants. While it is commonly assumed that nonunion accounts for most reoperations, we hypothesized that malposition is the leading cause of revision. The aim of this study was to determine the rate and reasons for revision after MTP1 arthrodesis using cup- and cone-reamers and the latest locking plate technology. Method: Between 2015 and 2017, 120 consecutive MTP1 fusions in 114 patients were performed with a low profile, pre-contoured titanium dorsal locking plate and a plantar metatarsophalangeal screw. The rate and reasons for revision within a minimum one-year follow-up period (average 16 months [12 - 26]) after index procedures were documented and analyzed. The revision was defined as any reoperation following the index procedure excluding hardware removal. Results: Seventeen of 120 feet (14%) underwent revision. Four patients developed a nonunion (3.3%) and needed revision, and 11 feet (9%) required revision for painful malposition; insufficient extension and excessive valgus accounted for the majority. Two patients required medial sesamoidectomy. No infection or wound healing problems occurred. Twelve patients requested hardware removal. Conclusions: Nonunion revision rate after MTP1 fusion with the latest locking plate technology is low. The leading cause of revision is malposition followed by nonunion. Excessive valgus and insufficient extension account for most symptomatic malposition. A recommendation of 0 - 10 degrees of valgus in the horizontal plane may contribute to diminishing revision rates; no conclusions could be drawn regarding an optimal position in the sagittal plane.

Computer-assisted orthopaedic surgery (CAOS) is a real-time navigation guidance system that supports surgeons intraoperatively. Its use is reported to increase precision and facilitate less-invasive surgery. Advanced intraoperative imaging helps confirm that the initial aim of surgery has been achieved and allows for immediate adjustment when required. The complex anatomy of the foot and ankle, and the associated wide range of challenging procedures should benefit from the use of CAOS; however, reports on the topic are scarce. This article explores the fields of applications of real-time navigation and CAOS in foot and ankle surgery. Cite this article: EFORT Open Rev 2021;6:531-538. DOI: 10.1302/2058-5241.6.200024

The coherence of light will be destroyed when propagate through scattering medium, which scrambles the transmitted light and thus forms speckle pattern behind. In order to understand the scattering process and implement applications such as imaging through scattering medium, theory for transmission matrix, eigenvectors have been studied and exploited. However, the Huygens–Fresnel principle implies that regional local effect of scattering process is existing, which could be involved in spatially engineered effective scattering particles, we name it scattering tunnels. We demonstrate the scattering tunneling effect in our experiment and implement this effect to achieve super resolution modes manipulation on input plane of scattering system. The scattering tunnels might introduce another perspective to study the scattering process, and provide researchers a way to improve efficiency of light control through scattering medium.

Conventional treatment of syndesmosis injuries in rotationally unstable ankle fractures is associated with an unacceptably high rate of malreduction, and this has led to a paradigm shift in the approach to a newer concept of anatomical repair. In the anatomical approach, the principle is to ‘directly fix what is broken and repair what is torn’. The approach is effective in reducing the rate of syndesmosis malreduction, increasing the biomechanical strength of syndesmosis fixation and avoiding the need for trans-syndesmotic fixation and its secondary removal. The objective of this review article is to compare the conventional treatment of these injuries (accepted usage, general consent, traditional, generally accepted) with a newer anatomical approach to be considered as a shift in thinking. Cite this article: EFORT Open Rev 2018;3:24-29. DOI: 10.1302/2058-5241.3.170017

We report the unusual case of a 16-year-old young man who sustained a rare association of a Hawkins' type-II talar neck fracture with a complete medial subtalar dislocation (Hawkins type-IIB) that occurred as an isolated injury after indirect trauma during a soccer game. Following closed reduction of the subtalar dislocation, standard radiographs and computed tomography (CT) demonstrated a comminuted fracture of the talus involving the base of the talar neck. Open reduction was performed and the fracture was stabilized by ORIF. At 1-year follow-up, functional and radiographic outcomes were graded as excellent, with no radiographic evidence of talar osteonecrosis.

Resume Nous rapportons le cas inhabituel d’un jeune homme de 16 ans qui presentait une association rare d’une fracture du col du talus de type Hawkins II avec une luxation sous-talienne mediale complete (type-IIB), survenue apres un traumatisme isole indirect au cours d’un match de football. Une fois la luxation sous-talienne reduite en urgence, des radiographies standard et une tomodensitometrie (TDM) ont mis en evidence une fracture comminutive de la base du col talien. Une osteosynthese stable a ciel ouvert a ete realisee. Au suivi a 1 an, les resultats fonctionnels et radiologiques sont excellents, avec l’absence d’apparition radiographique d’osteonecrose du talus.

Introduction Syndesmotic disruption may be difficult to reduce and fix, and malreduction is associated with inferior outcomes. Intraoperative computed tomography (CT) can provide accurate assessment of syndesmotic reduction. We hypothesized that three-dimensional (3-D) computer-assisted orthopaedic surgery (CAOS) with navigation of syndesmotic reduction could avoid malreduction. Our goal was to assess feasibility and accuracy of such a technic in a cadaveric study. Method Eleven through-the-knee cadaveric specimens were used. Ankle CT as control was obtained prior to intervention. The syndesmosis was destabilized by sectioning the tibiofibular ligaments, producing a malreduction temporarily fixed with a Kirschner wire (K-wire). With reference base fixed to the tibia an acquisition scan was made. A K-wire was fixed to the fibula. The K-wire holding the syndesmosis malreduced was removed. The fibula was reduced within the syndesmosis under 3-D CAOS using a navigated K-wire. Once optimal position was obtained by referencing control images, the syndesmosis was fixed with a 3.5 mm screw. A CT scan was performed to assess quality of reduction. Results Position of the fibula in control and post-reduction CT scans showed a mean anterior-posterior displacement of 0.74 (±0.62)mm. The medial-lateral position measured a mean displacement of 0.68 (±0.76)mm. Rotation of the fibula revealed a mean difference of 0.99° (± 0.73). Conclusion In this cadaveric study, CAOS with navigation allowed for very accurate syndesmosis reduction. This appears to be a promising technique to be confirmed by clinical study.

Purpose: The purpose of this study was to compare femoral head placement, rates of reoperation and cephalic implant cut-out of a screw versus a blade for patients over age 60 with low energy trochanteric fractures (AO/OTA 31-A1, A2, and A3) treated either with sliding hip screw or cephalomedullary nail. Methods: After surgeon selection of either hip screw or nail, hip screw patients were randomised to either a DHS (dynamic hip system screw) or DHS blade (dynamic hip system blade), while nail patients were randomised to either a Gamma3 Trochanteric Nail or a PFNA (proximal femoral nail antirotation). This resulted in a screw group (DHS and Gamma nail), and a blade group (DHS blade and PFNA). Outcome measures included tip-apex distance and zone location of the cephalic implant, as well as reoperation and implant cut-out within the first postoperative year. Results: A total of 335 patients were randomised, 172 to a screw and 163 to a blade. There was no significant difference concerning mean tip-apex distance, percentage of patients with a tip-apex distance >25mm, and patients with a centre-centre position of the cephalic implant. There were 137 patients in the screw group and 132 in the blade group available for follow-up. They did not differ regarding rates of reoperation or cut-out (screw group = 2.9%; blade group = 1.5%). Conclusions: Both a screw and a blade performed equally well in terms of implant placement in the femoral head and outcome

Purpose: The purpose of this study was to analyse the long-term incidence of dislocation arthropathy after a modified Latarjet procedure for glenohumeral instability. Methods: Long-term follow-up information was obtained from a consecutive series of patients who had undergone a modified Latarjet procedure by one surgeon between 1986 and 1999. Multivariable regression analysis was performed to examine the relation between the development of a dislocation arthropathy and patients and surgery-related factors. Results: There were 117 patients (117 shoulders) for evaluation, (35 women and 82 men) with a mean age 28.4 ± 8.5 (range, 16-55). The mean follow-up was 16.2years (range, ten to 22.2years). Signs of dislocation arthropathy were found in 36% of patients, graded as Samilson 1 in 30%, Samilson 2 in 3%, and 3% Samilson 3 in 3% of patients. Risk factors for dislocation arthropathy included surgery in patients older than 40years of age (64.3 vs. 34.4%; adjusted RR 2.2, 95% CI 1.7-2.9) and lateral positioning of the transferred coracoid process in relation to the glenoid rim (82.4 vs. 30.4%; adjusted RR 2.3, 95% CI 1.7-3.2). Patients with hyperlaxity developed less dislocation arthropathy (15 vs. 42.5%; adjusted RR 0.4, 95% CI 0.1-0.95). Conclusion: The development of dislocation arthropathy after the Latarjet procedure remains a source of concern in the long term. It correlates with surgery after the age of 40 and lateral coracoid transfer in relation to the glenoid rim. On the other hand, hyperlaxity seems to have a protective effect on the development of dislocation arthropathy

Background and aims: While hip fractures represent the most dramatic consequence of osteoporosis, fractures of the humerus, forearm and wrist account for one-third of the total incidence of fractures due to osteoporosis in the older population. The aim of this retrospective cohort study was to evaluate rehabilitation care utilization and associated factors in elderly individuals with upper limb fracture. Methods: Over two years, 667 patients 65 years of age or older were studied, who presented to the emergency department either from their private homes or nursing homes with an upper extremity fracture. The following outcome variables were collected: gender; age; residence; location of fracture; treatment; discharge destination; length of hospitalization; length of stay in a rehabilitation facility; and ultimate place of habitation after the event. Results: The most frequent sites of fracture were distal radius (37.2%) and proximal humerus (29.1%). Two-thirds of the patients were treated non-operatively. Inpatient rehabilitation care was necessary for 248 patients (37.2%; length of stay, 46 days). Factors associated with increased care included older age (≥80 years), coming from private home, sustaining two fractures, fractures of the humerus, and operative treatment. Six percent of the patients required permanent nursing home care. Conclusions: Upper extremity fractures in older people often require prolonged hospitalization and therefore account for considerable health care costs. Reasons are more related to advanced age and living conditions than to particular injury or treatment.

Purpose: In contrast to a large amount of epidemiological data regarding the incidence of implant infections after fracture management, surprisingly few have been published concerning the success of their treatment. Methods: This was a single-centre cohort study at Geneva University Hospitals from 2000 to 2012 investigating the remission rates of orthopaedic implant infections after fracture repair and associated variables. Results: A total of 139 episodes were included: There were 51 women (37%) and 28 immunosuppressed (20%) patients with a median age and American Society of Anaesthesiologists (ASA) score of 51years and 2 points, respectively. The infected implants were plates (n = 75, 54%), nails (24, 17%), wires (20), screws (10), cerclage cables or wires (3), hip screws (4) or material for spondylodesis (3). A pathogen was identified in 135 (97%) cases, including Staphylococcus aureus (73, 52%), coagulase-negative staphylococci (20), streptococci (7) and 19 Gram-negative rods. All patients underwent antibiotic treatment, and 128 (92%) remained in remission at a median follow-up time of 2.6years (range one to 13years). In multivariate logistic regression analysis, the plate infections were significantly associated with lower remission rates [65/75, 87%, odds ratio (OR) 0.1, 95% confidence interval (CI) 0.01-0.90]. No associations were found for gender, age, immune status, ASA score, additional surgical interventions (OR 0.4, 95% CI 0.1-4.1) or duration of antibiotic treatment (OR 1.0, 95% CI 0.98-1.01). Conclusions: Among all infected and removed orthopaedic implants, plates were associated with slightly lower remission rates, while the overall treatment success exceeded 90%. The duration of antibiotic therapy did not alter the outcome

Postoperative fever is often misinterpreted as a sign of infection, especially when occurring after the third postoperative day. We assessed the epidemiology of postoperative fever in adult orthopaedic patients and its association with infection. Among 1,073 patients participating in a prospective observational study, 198 (19%) had a postoperative fever (>38°C). Thirteen patients (1.2%) had a surgical site infection and 78 patients (7.3%) had remote bacterial infections during their hospital stay. Including asymptomatic bacteriuria, 174 patients were given antibiotic therapy for a median duration of six days. In multivariate analysis, no clinical parameter was associated with fever, including haematoma (odds ratio 0.9, 95%CI 0.6-1.3), infection (1.6, 0.7-3.7), or antibiotic use (1.6, 0.9-3.0). The maximum temperature on each of the first seven postoperative days did not differ between infected and uninfected patients (Wilcoxon rank-sum tests; p > 0.10). We conclude that fever, even up to the seventh postoperative day, is not substantially helpful to distinguish infection from general inflammation in clean orthopaedic surgery.

Pilon or tibial plafond fractures usually result from high-energy injuries with rotation and/or axial compression. They occur in an area of relatively poor soft tissue coverage and frequently present a surgical challenge in deciding which incisions will be best for performing open reduction internal fixation. A variety of anterior and posterior approaches have been described based on the ease of fracture reduction and internal fixation with plates. Some of the incisions are fracture specific, that is, planned for a limited approach to the pilon. But in more complex cases, a wider exposure is indicated and thus more extensile approaches, both anterior and posterior, can be valuable. This review article will describe the different surgical approaches, focusing on their indication and technique.

Case: We describe a case of ulcerative midfoot osteomyelitis in a patient with Charcot diabetic neuropathy. After debridement, an extensive osseous defect led to staged reconstruction in an attempt to salvage the foot. We describe the presentation, the treatment, and the technical points of this challenging case. Conclusion: We reconstructed the midfoot defect with use of the induced-membrane Masquelet technique, successfully reestablishing a stable, well-aligned, plantigrade, ulcer-free foot.

Despite the fact that there are numerous reports on muscular variations in the sole of the foot, routine dissection in a formaldehyde-fixed cadaver revealed an accessory flexor digiti quinti muscle, which to the best of our knowledge is a very unusual variant. This was in the form of a slender, 38 mm long muscular slip, with a proximal and distal tendon extending from the common flexor digitorum longus tendinous plate out to the distal phalanx of the fifth toe. An associated finding was the absence of the musculotendinous portion of the flexor digitorum brevis to the same toe. A developmental explanation for this variation is presented. Clinical implications with regard to this anatomical condition may result in clawing of the fifth toe.

OBJECTIVE Our objective is to review the anatomy and exposure of the posterior column and posterior tibial malleolus (the posterior tibial plafond) by defining the access corridors through 3 different approaches-posteromedial, posterolateral, and modified posteromedial. METHODS Cadaveric dissection with percentage of posterior tibial malleolus exposed, and strain gauge measurements to evaluate traction on the neurovascular bundle. RESULTS The 3 different approaches are applicable for exposure of different portions of the distal posterior tibial malleolus. Strain gauge measurements reveal the least traction on the flap containing the neurovascular bundle with the modified posteromedial approach (7.0 N) compared with the posteromedial (21.5 N) and posterolateral (16.8 N) approaches. Exposure of the posterior tibial malleolus was greater with the modified posteromedial approach (91%) compared with the other 2 approaches (posteromedial = 64%, posterolateral = 40%). CONCLUSIONS Depending on the location of the principal fracture fragments, particularly in high energy ankle and pilon fractures, each of the posterior approaches has its indication, with the modified posteromedial approach revealing more of the posterior anatomy than the other 2 approaches. The latter approach places the least traction on the flap containing the neurovascular bundle.

Chopart complex injuries (CCIs) are thought to be uncommon; however, recent literature states the rate of misdiagnosis to be between 20 and 41%. Chopart complex injuries are not ankle injuries, with which they are initially confused due to a similar mechanism of trauma in many cases. Injury to the Chopart complex commonly affects multiple structures. The key to optimal treatment is a high index of clinical suspicion combined with timely accurate imaging studies. Careful diagnostic workup with high-quality radiographs of the foot in neutral position should be obtained. Computed tomography (CT) and/or magnetic resonance imaging (MRI) are recommended to accurately assess bone and soft tissue injury. CCI frequently leads to prolonged swelling, pain and disability. In some cases, it may result in a posttraumatic flatfoot deformity.

Whether patients with asymptomatic bacteriuria should be investigated and treated before elective hip and knee replacement is controversial, although it is a widespread practice. We conducted a prospective observational cohort study with urine analyses before surgery and three days post-operatively. Patients with symptomatic urinary infections or an indwelling catheter were excluded. Post-discharge surveillance included questionnaires to patients and general practitioners at three months. Among 510 patients (309 women and 201 men), with a median age of 69 years (16 to 97) undergoing lower limb joint replacements (290 hips and 220 knees), 182 (36%) had pre-operative asymptomatic bacteriuria, mostly due to Escherichia coli, and 181 (35%) had white cells in the urine. Most patients (95%) received a single intravenous peri-operative dose (1.5 g) of cefuroxime as prophylaxis. On the third post-operative day urinary analysis identified white cells in 99 samples (19%) and bacteriuria in 208 (41%). Pathogens in the cultures on the third post-operative day were different from those in the pre-operative samples in 260 patients (51%). Only 25 patients (5%) developed a symptomatic urinary infection during their stay or in a subsequent three-month follow-up period, and two thirds of organisms identified were unrelated to those found during the admission. All symptomatic infections were successfully treated with oral antibiotics with no perceived effect on the joint replacement.We conclude that testing and treating asymptomatic urinary tract colonisation before joint replacement is unnecessary.Cite this article: Bone Joint J 2014;96-B:390–4.