InSPECtor: an end-to-end design framework for compressive pixelated hyperspectral instruments.

Classic designs of hyperspectral instrumentation densely sample the spatial and spectral information of the scene of interest. Data may be compressed after the acquisition. In this paper, we introduce a framework for the design of an optimized, micropatterned snapshot hyperspectral imager that acquires an optimized subset of the spatial and spectral information in the scene. The data is thereby already compressed at the sensor level but can be restored to the full hyperspectral data cube by the jointly optimized reconstructor. This framework is implemented with TensorFlow and makes use of its automatic differentiation for the joint optimization of the layout of the micropatterned filter array as well as the reconstructor. We explore the achievable compression ratio for different numbers of filter passbands, number of scanning frames, and filter layouts using data collected by the Hyperscout instrument. We show resulting instrument designs that take snapshot measurements without losing significant information while reducing the data volume, acquisition time, or detector space by a factor of 40 as compared to classic, dense sampling. The joint optimization of a compressive hyperspectral imager design and the accompanying reconstructor provides an avenue to substantially reduce the data volume from hyperspectral imagers.

Return to preinjury sports after anterior cruciate ligament reconstruction is predicted by five independent factors.

PURPOSE: To determine factors that predict return to the same frequency and type of sports participation with similar activity demands as before injury. METHODS: Individuals 1 to 5 years after primary ACL reconstruction completed a comprehensive survey related to sports participation and activity before injury and after surgery. Patient characteristics, injury variables, and surgical variables were extracted from the medical record. Return to preinjury sports (RTPS) was defined as: "Returning to the same or more demanding type of sports participation, at the same or greater frequency with the same or better Marx Activity Score as before injury." Variables were compared between individuals that achieved comprehensive RTPS and those that did not with univariate and multivariate logistic regression models. RESULTS: Two-hundred and fifty-one patients (mean age 26.1 years, SD 9.9) completed the survey at an average of 3.4 years (SD 1.3) after ACL reconstruction. The overall rate of RTPS was 48.6%. Patients were more likely to RTPS if they were younger than 19 years old (OR = 4.07; 95%CI 2.21-7.50; p < 0.01) or if they were competitive athletes (OR = 2.07; 95%CI 1.24-3.46; p = 0.01). Patients were less likely to RTPS if surgery occurred more than 3 months after injury (OR = 0.31, 95%CI 0.17-0.58; p < 0.01), if there was a concomitant cartilage lesion (OR = 0.38; 95%CI 0.21-0.70; p < 0.01), and if cartilage surgery was performed (OR = 0.17; 95%CI 0.04-0.80; p = 0.02). CONCLUSION: Five variables best predicted RTPS including age at time of surgery. Only time from injury to surgery is a potentially modifiable factor to improve RTPS; however, the reasons for which patients delayed surgery may also contribute to them not returning to sports. Regardless, younger patients, those that partake in sports on a competitive level, those that undergo surgery sooner, or do not have a cartilage injury or require cartilage surgery are more likely to return to pre-injury sports participation. LEVEL OF EVIDENCE: III.

Ten-year revision rates of contemporary total ankle arthroplasties equal 22%. A meta-analysis.

BACKGROUND: The National Institute for Health and Care Excellence criterion for hip replacements is a (projected) revision rate of less than 5% after 10 years. No such criterion is available for ankle prostheses. The objective of the current study is to compare survival rates of contemporary primary ankle prostheses to the hip-benchmark. METHODS: The PRISMA methodology was used. Eligible for inclusion were clinical studies reporting revision rates of currently available primary total ankle prostheses. Data was extracted using preconstructed forms. The total and prosthesis-specific annual revision rate was calculated. RESULTS: Fifty-seven articles of eight different ankle prostheses were included (n = 5371), totaling 513 revisions at an average 4.6 years of follow-up. An annual revision rate of 2.2 was found (i.e. an expected revision rate of 22% at 10 years). CONCLUSIONS: The expected 10-year revision rate of contemporary ankle prostheses is lower than the current benchmark for hip prostheses.

LOUPE: observing Earth from the Moon to prepare for detecting life on Earth-like exoplanets.

LOUPE, the Lunar Observatory for Unresolved Polarimetry of the Earth, is a small, robust spectro-polarimeter for observing the Earth as an exoplanet. Detecting Earth-like planets in stellar habitable zones is one of the key challenges of modern exoplanetary science. Characterizing such planets and searching for traces of life requires the direct detection of their signals. LOUPE provides unique spectral flux and polarization data of sunlight reflected by Earth, the only planet known to harbour life. These data will be used to test numerical codes to predict signals of Earth-like exoplanets, to test algorithms that retrieve planet properties, and to fine-tune the design and observational strategies of future space observatories. From the Moon, LOUPE will continuously see the entire Earth, enabling it to monitor the signal changes due to the planet's daily rotation, weather patterns and seasons, across all phase angles. Here, we present both the science case and the technology behind LOUPE's instrumental and mission design. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades'.

Increasing consensus on terminology of Achilles tendon-related disorders.

PURPOSE: Aims of this study are to evaluate the current terminology and assess the influence of the latest proposals on the terminology used for Achilles tendon-related disorders in both daily practice and literature. METHODS: (1) All orthopedic surgeons experienced in the field of foot and ankle surgery of the Ankleplatform Study Group were invited to participate in this survey by email. They were requested to fill out a survey on terminology in six typical cases with Achilles tendon-related disorders. (2) A systematic literature search of Achilles tendon-related disorders was performed in eight foot and ankle journals in Medline, Embase (Classic) from 2000 to 2016. All extracted terms were counted and compared to the terminology proposals, based on anatomic location, symptoms, clinical findings and histopathology. RESULTS: (1) In total, 141 of the 283 (50%) orthopedic surgeons responded to the survey. In five out of six cases with Achilles tendon-related disorders, the majority gave an answer according to latest proposals. (2) An overview of terminology used for Achilles tendon-related disorders from 2000 to 2016 shows an increase in use of terminology according to the latest proposals based on anatomic location, symptoms, clinical findings and histopathology. CONCLUSION: The revised terminology for Achilles tendon-related disorders based on anatomic location, symptoms, clinical findings and histopathology is used by the majority of orthopedic surgeons and is increasingly used in the literature. However, the indistinct Haglund eponyms are still frequently used in Achilles tendon-related terminology. LEVEL OF EVIDENCE: Level IV.

High patient satisfaction and good long-term functional outcome after endoscopic calcaneoplasty in patients with retrocalcaneal bursitis.

PURPOSE: The primary objective of this study was to determine the degree of patient satisfaction at a minimum of 5 years of follow-up after endoscopic calcaneoplasty. The secondary objectives were to assess functional outcome measures, pain scores, analysis of bone removal, reformation of exostosis at follow-up and correlation of the size of the exostosis and recurrent or persisting complaints. METHODS: This study evaluated patients who underwent endoscopic calcaneoplasty, between January 1st 2000 and December 31st 2010, for the diagnosis of retrocalcaneal bursitis. The evaluation consisted of PROMs (patient-reported outcome measures), a questionnaire and a visit to the outpatient clinic for physical examination and a standard lateral weight-bearing radiograph of the ankle. Patient satisfaction, functional outcomes and pain scores were measured by use of a numeric rating scale (NRS). Size of the posterosuperior calcaneal exostosis was measured on a standard lateral weight-bearing radiograph using parallel pitch lines (PPL) and the Fowler-Philip angle (PFA). RESULTS: The response rate was 28 out of 55 (51%) and the median time to follow-up was 101(IQR 88.5-131.8) months. The median satisfaction score for treatment results was 8.5 out of 10 (IQR 6-10). FAOS symptoms 84.5 (IQR 58.0-96.4), FAOS pain 90.3 (IQR 45.1-100.0), FAOS ADL 94.9 (IQR 58.1-100.0), FAOS sport 90.0 (IQR 36.3-100.0) and FAOS QOL 71.9 (IQR 37.5-93.8) and median AOFAS was 100 (IQR 89-100). The median PLL difference between before operation and 2 weeks after the operation was - 4 mm (IQR-6 and -1) and the median PLL difference between 2 weeks after the operation and at follow-up was 1 mm (0-2). The median PFA was 65 (63-69) at baseline, 66.5 (60.8-70.3) 2 weeks after the operation and 64 (60.8-65.3) at follow-up. CONCLUSION: Despite the limited response rate, this study shows high patient satisfaction and good long-term functional outcome in patients affected by retrocalcaneal bursitis who underwent endoscopic calcaneoplasty. LEVEL OF EVIDENCE: Level IV.

Geometrical characteristics of the symptomatic and non-symptomatic ossa trigona.

BACKGROUND: Posterior ankle impingement is strongly associated with the presence of an os trigonum, however, most patients with an os trigonum will never develop symptoms. It is hypothesized that the os trigonum is larger in the symptomatic ankle than in the non-symptomatic ankle, the distance between os trigonum and tibia is smaller and there are more degenerative changes in ankles with symptoms of posterior impingement. In this study the geometrical characteristics of the ipsilateral and contralateral os trigonum are compared in patients with a bilateral os trigonum and unilateral posterior impingement symptoms. METHODS: Patients with a bilateral os trigonum and unilateral posterior impingement complaints were included. Comparison between the symptomatic and asymptomatic ankles was done within each patient. From the CT-scan of each ankle, the tibia, fibula, calcaneus, talus and os trigonum were segmented and a geometric model was created. Based on these bone models, the volume of the os trigonum and talus, the size of the os trigonum, the distance between os trigonum and surrounding bones (talus, calcaneus, fibula and tibia) were calculated. In addition, the CT images were assessed for the type of os trigonum, the presence of cysts, irregular synchondrosis, calcifications and whether the os trigonum consisted of more than one fragment. RESULTS: A total of 22 patients were included in this study. In seventeen of the 22 patients, the symptomatic os trigonum was larger in comparison with the non-symptomatic side in terms of length (median Δ 2.4 mm, 8.9 versus 10.6 mm) and relative volume (median Δ 0.09%, 0.30 versus 0.45% of talar volume). Distances between the ossa trigona and surrounding bones were not statistically significantly different between both sides. Calcifications were more frequently found around the os trigonum in the symptomatic side (10 versus 3/22). CONCLUSIONS: The findings in this study support the hypothesis that symptomatic ossa trigona are larger in comparison with asymptomatic ossa trigona. Calcifications around the os trigonum were found more frequently in symptomatic than in non-symptomatic ossa trigona. LEVEL OF EVIDENCE: III.

The calcaneofibular ligament has distinct anatomic morphological variants: an anatomical cadaveric study.

PURPOSE: The purpose of this study was to investigate if the calcaneofibular ligament (CFL) presents morphologic variants and measure the morphometrics of the ligament and its footprints METHODS: An anatomical study of 47 fresh-frozen below-the-knee ankle specimens was performed. Lateral ankle structures were dissected to expose the CFL. Overdissection was avoided to not modify the native morphology. The morphology (number and orientation of CFL bundles) and measurements of CFL insertions were recorded with ankle secured in neutral position. RESULTS: Four distinct morphological-oriented shapes of the CFL were observed. These included single bundle, Y-shape double bundle, V-shape double bundle, and associated with the lateral talocalcaneal ligament. The most frequent CFL morphology observed was the single bundle and the Y-shape double bundle, present in 21 (44.7%) and 13 (27.7%) ankles. The V-shape double bundle and the CFL double bundle associated with the lateral talocalcaneal ligaments were less common, appearing only in eight (17.0%) and five (10.6%) ankles. The CFL length was higher in single bundle and Y-shaped double bundle CFL variants, about 30 mm each. Footprint morphometrics were heterogenous amongst the different CFL variants. CONCLUSION: The CFL presents four distinct morphological-oriented shapes. The double bundle, V-shaped and Y-shaped CFL variants are uncommon and poorly reported in the literature. Their relation to the lateral talocalcaneal ligament and the inferior fascicle of the anterior talofibular ligament requires further research. The CFL morphology provides detailed knowledge of CFL anatomy that can improve diagnostic procedures. Furthermore, this information can fine-tune graft selection and sizing and allow a more precise anatomic placement during surgical reconstruction.

The arthroscopic syndesmotic assessment tool can differentiate between stable and unstable ankle syndesmoses.

PURPOSE: Patients with stable isolated injuries of the ankle syndesmosis can be treated conservatively, while unstable injuries require surgical stabilisation. Although evaluating syndesmotic injuries using ankle arthroscopy is becoming more popular, differentiating between stable and unstable syndesmoses remains a topic of on-going debate in the current literature. The purpose of this study was to quantify the degree of displacement of the ankle syndesmosis using arthroscopic measurements. The hypothesis was that ankle arthroscopy by measuring multiplanar fibular motion can determine syndesmotic instability. METHODS: Arthroscopic assessment of the ankle syndesmosis was performed on 22 fresh above knee cadaveric specimens, first with all syndesmotic and ankle ligaments intact and subsequently with sequential sectioning of the anterior inferior tibiofibular ligament, the interosseous ligament, the posterior inferior tibiofibular ligament, and deltoid ligaments. In all scenarios, four loading conditions were considered under 100N of direct force: (1) unstressed, (2) a lateral hook test, (3) anterior to posterior (AP) translation test, and (4) posterior to anterior (PA) translation test. Anterior and posterior coronal plane tibiofibular translation, as well as AP and PA sagittal plane translation, were arthroscopically measured. RESULTS: As additional ligaments of the syndesmosis were transected, all arthroscopic multiplanar translation measurements increased (p values ranging from p < 0.001 to p = 0.007). The following equation of multiplanar fibular motion relative to the tibia measured in millimeters: 0.76*AP sagittal translation + 0.82*PA sagittal translation + 1.17*anterior third coronal plane translation-0.20*posterior third coronal plane translation, referred to as the Arthroscopic Syndesmotic Assessment tool, was generated from our data. According to our results, an Arthroscopic Syndesmotic Assessment value equal or greater than 3.1 mm indicated an unstable syndesmosis. CONCLUSIONS: This tool provides a more reliable opportunity in determining the presence of syndesmotic instability and can help providers decide whether syndesmosis injuries should be treated conservatively or operatively stabilized. The long-term usefulness of the tool will rest on whether an unstable syndesmosis correlates with acute or chronic clinical symptoms.

Cryotherapy after Total Knee Arthroplasty provides faster recovery and better ranges of motion in short term follow up. Results of a prospective comparative study.

Cryotherapy is applied in Total Knee Arthroplasty (TKA) to improve functional outcome. The aim of this study is to investigate whether an advanced cryotherapy device does not increase the risk of complications and improves knee function or decreases swelling. A prospective cohort of TKA patients was formed by a cryotherapy group and a control group. The primary outcome was complication ratio. Our secondary outcomes were functional results and swelling. No significant differences were found in complication ratio between 31 patients in the cryotherapy group and 31 patients in the control group. The cryotherapy group showed a significant better knee flexion and less swelling in the early rehabilitation phase. No differences were found at the other follow-up moments or in the other outcomes. This advanced cryotherapy device is safe in respect of postoperative complications, improves knee function and decreases swelling in the early rehabilitation phase. However, it is questionable if an advanced cryotherapy device with its additional costs is necessary to provide the desired effects of cryotherapy.

Surgical treatment for posteromedial talar process fractures.

PURPOSE: The first descriptions on medial talar tubercle fractures are attributed to Cedell. He described avulsion fractures of the insertion of the posterior talotibial ligament. However the true etiology has not been established. Since little is known about these fractures, they are easily misdiagnosed as simple ankle sprains. Untreated, these fractures may lead to chronic ankle pain. To improve the understanding of the etiology and outcome of these fractures a systematic review was conducted of all cases of isolated fractures of the medial tubercle of the posterior talar process. In addition we present the first series of competitive athletes treated by means of the two-portal hindfoot approach for isolated medial talar tubercle fractures. METHODS: A systematic search was performed to identify all cases of medial tubercle fractures. Data on trauma mechanism, clinical presentation, imaging and treatment were extracted. In addition we retrospectively report on the results of endoscopically treated patients in our institution over the last fifteen years. Of all patients Numeric Rating Scores (NRS) for Satisfaction, Pain and Function, Foot Ankle Outcome Scores (FAOS), return to sport and complications were reported. RESULTS: Eightteen articles were included reporting on 33 patients with an isolated fracture or avulsion of the posteromedial talar process. Most of the fractures occurred during sport activities (58%), followed by motor vehicle accidents (21%) and fall from height (12%). Of the activities during sport, 73% resulted following an ankle sprain. Reasonable to good outcomes are described in cases treated with immobilization, open reduction internal fixation or open excision. Of the nine patients treated in our institution, five were male and the median age was 29. All were participating in sports at a competitive level, with four of them being a professional athlete. In most patients the diagnosis was made more than a year after initial trauma. Ankle sprain was most common trauma mechanism. In some patients it was evident the avulsion was part or the deep portion of the deltoid ligament, however in two cases it was more likely an avulsion of the flexor hallucis longus (FHL) retinaculum. The median follow-up was 69 months (IQR 12.0-94.3). At final follow-up patients had little pain, NRS 1. Median NRS for satisfaction and function were 7 and 8, respectively. All patients did resume sport activities, however only four reached the preinjury level. Of the five patients that did not return to their pre-injury level of activity, two were professional athletes at the end of their career, and retired not due to ankle complaints. One complication was reported. CONCLUSION: Fractures of the medial tubercle are rare and based on the available literature there is not one distinct trauma mechanism. Based on literature no recommendation for treatment can be made. Our results show endoscopic excision of the fragment as a save alternative for open surgical treatment.

The accuracy of an injection technique for Flexor hallucis longus tendon sheath: A cadaveric study.

BACKGROUND: Corticosteroid injections are used in the conservative treatment of Flexor hallucis longus (FHL) tendinopathy. Studies for imaging guided injection are done, however, the accuracy of blind injection has not yet been studied. PURPOSE: The aim of this study was to determine the accuracy of a blind injection technique into the FHL tendon sheath. HYPOTHESIS: We hypothesize that a blind injections technique into the FHL tendon sheath based on clinical examination has a high accuracy. STUDY DESIGN: Descriptive cadaveric study. METHODS: Ten ankles of human cadavers were blindly injected with radiologic contrast mixed with methylene blue into the FHL tendon sheath. After injection, a CT scan of each ankle was performed to evaluate the location of contrast material. CT scans were reviewed by an experienced musculoskeletal radiologist blinded to the procedure. Anatomic dissection was undertaken to assess the location of the injection fluid. RESULTS: In nine ankles the radiological contrast was injected in the FHL tendon sheath. In one cadaver there was a technical problem and was therefore excluded. CONCLUSION: This study shows that the FHL tendon sheath can be blindly injected based on only clinical examination with high accuracy. LEVEL OF EVIDENCE: Descriptive cadaveric study.

The effect of foot rotation on measuring ankle alignment using simulated radiographs: a safe zone for pre-operative planning.

AIM: To assess whether variation in foot rotation, in relation to camera position, affects the reliability of measurement of hindfoot alignment on radiographs and to define a "safe zone" where measurement of the alignment axis and thus preoperative planning is not affected by foot rotation. MATERIALS AND METHODS: Healthy volunteers were recruited of whom double-sided lower-leg weight-bearing computed tomography (CT) was acquired. Weight-bearing was simulated by means of providing axial compression force equal to the weight of the healthy volunteers. The scans were uploaded into custom-made three-dimensional analysis software to create digitally reconstructed radiographs. For each CT examination, a coordinate system was determined, which defines the neutral position of the leg. Rotation about the z-axis of this coordinate system simulates endo- and exorotation of the foot. Subsequently, radiographs were reconstructed for the leg between 30° of endorotation and 45° of exorotation, and the relation between the observed alignment axis and foot rotation was determined. RESULTS: A total of 20 healthy volunteers were included, 10 males (mean age 37.7±11.1) and 10 females (mean age 34±10.3). Per 5° of leg rotation, the alignment axis translated with a mean of 6.86% (SD ±13.1). No significant difference in position of the alignment axis was seen between 10° of endorotation and 10° of exorotation compared to the neutral ankle position. CONCLUSION: The "safe zone" for imaging the hindfoot alignment axis, is between 10° endo- and 10° exorotation of the foot.

Emerging Concepts in Treating Cartilage, Osteochondral Defects, and Osteoarthritis of the Knee and Ankle.

The management and treatment of cartilage lesions, osteochondral defects, and osteoarthritis remain a challenge in orthopedics. Moreover, these entities have different behaviors in different joints, such as the knee and the ankle, which have inherent differences in function, biology, and biomechanics. There has been a huge development on the conservative treatment (new technologies including orthobiologics) as well as on the surgical approach. Some surgical development upraises from technical improvements including advanced arthroscopic techniques but also from increased knowledge arriving from basic science research and tissue engineering and regenerative medicine approaches. This work addresses the state of the art concerning basic science comparing the knee and ankle as well as current options for treatment. Furthermore, the most promising research developments promising new options for the future are discussed.

Diagnosis, treatment and prevention of ankle sprains: update of an evidence-based clinical guideline.

This guideline aimed to advance current understandings regarding the diagnosis, prevention and therapeutic interventions for ankle sprains by updating the existing guideline and incorporate new research. A secondary objective was to provide an update related to the cost-effectiveness of diagnostic procedures, therapeutic interventions and prevention strategies. It was posited that subsequent interaction of clinicians with this guideline could help reduce health impairments and patient burden associated with this prevalent musculoskeletal injury. The previous guideline provided evidence that the severity of ligament damage can be assessed most reliably by delayed physical examination (4-5 days post trauma). After correct diagnosis, it can be stated that even though a short time of immobilisation may be helpful in relieving pain and swelling, the patient with an acute lateral ankle ligament rupture benefits most from use of tape or a brace in combination with an exercise programme.New in this update: Participation in certain sports is associated with a heightened risk of sustaining a lateral ankle sprain. Care should be taken with non-steroidal anti-inflammatory drugs (NSAIDs) usage after an ankle sprain. They may be used to reduce pain and swelling, but usage is not without complications and NSAIDs may suppress the natural healing process. Concerning treatment, supervised exercise-based programmes preferred over passive modalities as it stimulates the recovery of functional joint stability. Surgery should be reserved for cases that do not respond to thorough and comprehensive exercise-based treatment. For the prevention of recurrent lateral ankle sprains, ankle braces should be considered as an efficacious option.

Endoscopic Treatment of Mid-Portion Achilles Tendinopathy: A Retrospective Case Series of Patient Satisfaction and Functional Outcome at a 2- to 8-Year Follow-up.

PURPOSE: To evaluate the results of endoscopic treatment in patients affected by mid-portion Achilles tendinopathy, by release of the paratenon combined with a resection of the plantaris tendon, regarding patient satisfaction, functional outcome, and pain scores. METHODS: This retrospective study evaluated patients endoscopically treated for mid-portion Achilles tendinopathy between 2000 and 2013. Patient satisfaction, functional outcome, pain scores, and health-related quality of life were measured by the use of a numeric rating scale, the Foot and Ankle Outcome Score, the Victorian Institute of Sport assessment for the Achilles tendon, the numeric rating scale for pain during running and during sports, and the EuroQol 5D (EQ-5D-3L) standardized questionnaire. Additional questions were asked on the effectiveness of the treatment and sport participation. RESULTS: The response rate was 76.3% (45 of 59). Thirty-five (78%) patients were treated unilaterally and 10 (22%) patients were treated bilaterally. For the unilaterally treated patients, the median time to follow-up was 67 months (interquartile range [IQR] 48-99 months), and for the bilaterally treated patients, it was 89.5 months (IQR 37.5-161.75 months). The median satisfaction score for treatment results was 9 out of 10 (IQR 7-10) and 9.5 (IQR 7-10), respectively. The median Foot and Ankle Outcome Score subscales were scored 75 to 99 and 75 to 97, the median Victorian Institute of Sport assessment for the Achilles tendon scored 81 (IQR 47-90) and 97 (IQR 87-100), and the median numeric rating scale pain scores during both running and sports were 1 (IQR 0-6.5) for the unilaterally treated patients and 0 (IQR 0-4.5) and 0 (IQR 0-1) for the bilaterally treated patients, respectively. The median EQ-5D were 0.81 (IQR 0.71-1) and 1 (IQR 0.64-1), respectively. One reoperation for recurrence of symptoms was necessary. CONCLUSIONS: This study shows high patient satisfaction and good functional outcomes in patients affected by mid-portion Achilles tendinopathy who were endoscopically treated by means of release of the paratenon in combination with transection of the plantaris tendon. LEVEL OF EVIDENCE: Level IV, retrospective case series (therapeutic).

Anatomic stabilization techniques provide superior results in terms of functional outcome in patients suffering from chronic ankle instability compared to non-anatomic techniques.

PURPOSE: To determine the best surgical treatment for chronic ankle instability (CAI) a systematic review was performed to compare the functional outcomes between various surgical stabilization methods. METHODS: A systematic search was performed from 1950 up to April 2016 using PubMed, EMBASE, Medline and the Cochrane Library. Inclusion criteria were a minimum age of 18 years, persistent lateral ankle instability, treatment by some form of surgical stabilization, described functional outcome measures. Exclusion criteria were case reports, (systematic) reviews, articles not published in English, description of only acute instability or only conservative treatment, medial ankle instability and concomitant injuries, deformities or previous surgical treatment for ankle instability. After inclusion, studies were critically appraised using the Modified Coleman Methodology Score. RESULTS: The search resulted in a total of 19 articles, including 882 patients, which were included in this review. The Modified Coleman Methodology Score ranged from 30 to 73 points on a scale from 0 to 90 points. The AOFAS and Karlsson Score were the most commonly used patient-reported outcome measures to assess functional outcome after surgery. Anatomic repair showed the highest post-operative scores [AOFAS 93.8 (SD ± 2.7; n = 119); Karlsson 95.1 (SD ± 3.6, n = 121)], compared to anatomic reconstruction [AOFAS 90.2 (SD ± 10.9, n = 128); Karlsson 90.1 (SD ± 7.8, n = 35)] and tenodesis [AOFAS 86.5 (SD ± 12.0, n = 10); Karlsson 85.3 (SD ± 2.5, n = 39)]. Anatomic reconstruction showed the highest score increase after surgery (AOFAS 37.0 (SD ± 6.8, n = 128); Karlsson 51.6 (SD ± 5.5, n = 35) compared to anatomic repair [AOFAS 31.8 (SD ± 5.3, n = 119); Karlsson 40.9 (SD ± 2.9, n = 121)] and tenodesis [AOFAS 19.5 (SD ± 13.7, n = 10); Karlsson 29.4 (SD ± 6.3, n = 39)] (p < 0.005). CONCLUSION: Anatomic reconstruction and anatomic repair provide better functional outcome after surgical treatment of patients with CAI compared to tenodesis reconstruction. These results further discourage the use of tenodesis reconstruction and other non-anatomic surgical techniques. Future studies may be required to indicate potential value of tenodesis reconstruction when used as a salvage procedure. Not optimal, but the latter still provides an increase in functional outcome post-operatively. Anatomic reconstruction seems to give the best results, but may be more invasive than anatomic repair. This has to be kept in mind when choosing between reconstruction and repair in the treatment of CAI. LEVEL OF EVIDENCE: IV.

The Cumberland Ankle Instability Tool (CAIT) in the Dutch population with and without complaints of ankle instability.

PURPOSE: To develop a translated Dutch version of the Cumberland Ankle Instability Tool (CAIT) and test its psychometric properties in a Dutch population with foot and ankle complaints. METHODS: The CAIT was translated into the Dutch language using a forward-backward translation design. Of the 130 subsequent patients visiting the outpatient clinic for foot and ankle complaints who were asked to fill out a questionnaire containing the CAIT, the Foot and Ankle Outcome Score (FAOS), and the numeric rating scale (NRS) pain, 98 completed the questionnaire. After a 1-week period, patients were asked to fill out a second questionnaire online containing the CAIT and NRS pain. This second questionnaire was completed by 70 patients. With these data, the construct validity, test-retest reliability, internal consistency, measurement error, and ceiling and floor effects were assessed. Additionally, a cut-off value to discriminate between stable and unstable ankles, in patients with ankle complaints, was calculated. RESULTS: Construct validity showed moderate correlations between the CAIT and FAOS subscales (Spearman's correlation coefficient (SCC) = 0.36-0.43), and the NRS pain (SCC = -0.55). The cut-off value was found at 11.5 points of the total CAIT score (range 0-30). Test-retest reliability showed to be excellent with an intraclass correlation coefficient of 0.94. Internal consistency was high (Cronbach's α = 0.86). No ceiling or floor effects were detected. CONCLUSION: Based on the results, the Dutch version of the CAIT is a valid and reliable questionnaire to assess ankle instability in the Dutch population and is able to differentiate between a functionally unstable and stable ankle. The tool is the first suitable tool to objectify the severity of ankle instability specific complaints and assess change in the Dutch population. Level of evidence II.