Arthroscopic repair of ankle instability with all-soft knotless anchors

In recent years, arthroscopic and arthroscopically assisted techniques have been increasingly used to reconstruct the lateral ligaments of the ankle. Besides permitting the treatment of several comorbidities, arthroscopic techniques are envisioned to lower the amount of surgical aggression and to improve the assessment of anatomic structures. We describe our surgical technique for arthroscopic, two-portal ankle ligament repair using an all-soft knotless anchor, which is made exclusively of suture material. This technique avoids the need for classic knot-tying methods. Thus it diminishes the chance of knot migration caused by pendulum movements. Moreover, it avoids some complications that have been related to the use of metallic anchors and some currently available biomaterials. It also prevents prominent knots, which have been described as a possible cause of secondary complaints.info:eu-repo/semantics/publishedVersio

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

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. 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. 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). 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. I

Typical shape differences in the subtalar joint bones between subjects with chronic ankle instability and controls

Bone shapes, particularly those defining the subtalar joint (STJ), have not received much attention yet as a risk factor for developing chronic ankle instability (CAI) after sustaining a lateral ankle sprain (LAS). This study aimed to compare three-dimensional (3D) shape variations in the STJ bones within individuals with CAI and healthy controls. 3D statistical shape models (SSMs) of the STJ bones were built to describe the bone shape variations observed within a population consisting of 26 individuals with unilateral CAI and 26 healthy controls. Using the SSMs and analysis of covariance test, age- and gender-adjusted shape variations in the bones were compared within individuals with CAI and healthy controls. The mean age of the CAI patients (14 males and 12 females) and healthy controls (12 males and 14 females) was 29 (standard deviation [SD] = 11) and 36 years (SD = 11), respectively. Tali and calcanei did not significantly vary between ipsilateral CAI and their contralateral ankle. Two shape modes, one for the talus (p = 0.015, variations in the curvature of the talar lateral process and the inclination angle of the talar neck relative to the body) and one for the calcaneus (p = 0.003, variations in the medial and lateral tuberosities, and the contour of the anterior articular surface), described significant shape differences between the CAI patients and healthy controls. The CAI patients generally had flatter talar joint surfaces and a flattened calcaneal ground-contact surface. These findings suggest that specific bone shapes may increase the risk of developing CAI after sustaining a LAS.Biomaterials & Tissue Biomechanic

A risk assessment model for chronic ankle instability: Indications for early surgical treatment? An observational prospective cohort - Study protocol

Background: Chronic ankle instability (CAI) is a common result of an ankle sprain. Even though early surgical treatment yields the best results, overall only professional athletes are eligible for acute surgical stabilization. Treating all patients with early surgical stabilization leads to a high amount of unnecessary invasive interventions, as not all patients progress to CAI. If patients at risk of developing CAI can be identified, treatment policies may be applied more effectively and efficiently. The purpose of this study is to develop a risk assessment model to identify patients at risk for CAI that should receive early surgical treatment. Methods: In this observational prospective cohort, all patients aged sixteen years and older, reporting at the emergency department of one of the participating hospitals after sustaining a lateral ankle sprain, and filled out 1 out of 3 follow-up questionnaires and the 1 year follow-up are included. A lateral and anteroposterior radiograph is made. Patients are excluded if a fracture or other pathology is present. The included patients receive four questionnaires, including questions focusing on the sprain, treatment and complaints, the Foot and Ankle Outcome Score and the Cumberland Ankle Instability Tool. A total of eleven radiographic variables are assessed for inter- and intra-observer reliability. Additionally, four factors extracted from the questionnaires, will be evaluated for correlation with CAI. Significantly correlating factors (e.a. risk factors) will be implemented in a risk assessment model. For the final model, based on sixteen variables with a minimum of 20 events per variable and a prevalence of 30-40% after an initial sprain, a sample size of 2370 patients is needed to perform both internal and external model validation. Discussion: This study will develop the first large scale model for the risk at CAI after an ankle sprain combining radiographic and patient characteristics. With this risk assessment model, patients at risk for CAI may be identified and properly informed on the treatment options. Patients identified as being at risk, may receive more adequate follow-up and become eligible for early surgical stabilization. This prevents patients from experiencing unnecessary long-lasting complaints, increasing the success rate of conservative and surgical treatment. Trial registration: Retrospectively registered: NCT02955485 [Registration date: 3-11-2016]. NTR6139 [Registration date: 3-1-2017]

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

Lower leg symmetry: a Q3D-CT analysis

Purpose: In fracture and realignment surgery, the contralateral unaffected side is often used as a model or template for the injured bone even though clinically valuable quantitative data of bilateral symmetry are often unavailable. Therefore, the objective of the present study was to quantify and present the bilateral symmetry of the tibia and fibula. Methods: Twenty bilateral lower-leg CT scans were acquired in healthy volunteers. The left and right tibia and fibula were segmented resulting in three-dimensional polygons for geometrical analyses (volume, surface and length). The distal and proximal segment of the right tibia of each individual was subsequently matched to the left tibia to quantify alignment differences (translation and rotation). Bone symmetry on group level was assessed using the Student’s t test and intra-individual differences were assessed using mixed-models analyses. Results: Intra-individuals differences were found for tibia volume (5.2 ± 3.3 cm3), tibia surface (5.2 ± 3.3 cm2), translations in the lateral (X-axis; 9.3 ± 8.9 mm) and anterior direction (Y-axis; 7.1 ± 7.0 mm), for tibia length (translation along Z-axis: 3.1 ± 2.4 mm), varus/valgus (φz: 1.7o ± 1.4°), and endotorsion/exotorsion (φz: 4.0o ± 2.7°). Conclusion: This study shows intra-individual tibia asymmetry in both geometric and alignment parameters of which the surgeon needs to be aware in pre-operative planning. The high correlation between tibia and fibula length allows the ipsilateral fibula to aid in estimating the original tibia length post-injury. Future studies need to establish whether the found asymmetry is clinically relevant when the contralateral side is used as reference in corrective surgery. Level of evidence: III cohort study

Translation of 3D Anatomy to 2D Radiographic Angle Measurements in the Ankle Joint: Validity and Reliability

Background: The objective consisted of 2 elements, primarily to define 2 bone geometry variations of the ankle that may be of prognostic value on ankle instability and secondly to translate these bone variations from a 3D model to a simple 2D radiographic measurement for clinical use. Methods: The 3D tibial and talar shape differences derived from earlier studies were translated to two 2D radiographic parameters: the medial malleolar height angle (MMHA) and talar convexity angle (TCA) respectively to ensure clinical use. To assess validity, the MMHA and TCA were measured on 3D polygons derived from lower leg computed tomographic (CT) scans and 2D digitally reconstructed radiographs (DRRs) of these polygons. To assess reliability, the MMHA and TCA were measured on standard radiographs by 2 observers calculating the intraclass correlation coefficient (ICC). Results: The 3D angle measurements on the polygons showed substantial to excellent agreement with the 2D measurements on DRR for both the MMHA (ICC 0.84-0.93) and TCA (ICC 0.88-0.96). The interobserver reliability was moderate with an ICC of 0.58 and an ICC of 0.64 for both the MMHA and TCA, respectively. The intraobserver reliability was excellent with an ICC of 0.96 and 0.97 for the MMHA and the TCA, respectively. Conclusion: Two newly defined radiographic parameters (MMHA and TCA) are valid and can be assessed with excellent intraobserver reliability on standard radiographs. The interobserver reliability was moderate and indicates training is required to ensure uniformity in measurement technique. The current method may be used to translate more variations in bone shape prior to implementation in clinical practice. Level of Evidence: Level III, cohort study.Biomaterials & Tissue Biomechanic

Surgical treatment paradigms of ankle lateral instability, osteochondral defects and impingement

Ankle sprain is amongst the most frequent musculoskeletal injuries, particularly during sports activities. Chronic ankle instability (CAI) resulting from an ankle sprain might have severe long-lasting consequences on the ankle joint. Despite the fact that most patients will respond favourably to appropriate conservative treatment, around 20% will develop symptomatic CAI with sense of giving away and recurrent sprains leading to functional impairment. “Classical” surgical repair by Brostrom-like surgery in one of its many modifications has achieved good results over the years. Recently, major advances in surgical techniques have enabled arthroscopic repair of ankle instability with favourable outcome while also enabling the treatment of other concomitant lesions: loose bodies, osteochondral defects (OCDs) or ankle impingement. Moreover, when the tissue remnant does not permit a repair technique, anatomic reconstruction by means of using a free graft has been developed. In many cases, OCDs occur as a consequence of CAI. However, traumatic and non-traumatic aetiologies have been described. There is no evidence favouring any surgical treatment over another concerning OCDs. Considering lower cost and limited aggression, microfracture is still the most frequent surgical approach. Herein, the authors describe their algorithm in the treatment of these conditions. Similarly, anterior or posterior impingement might be linked with CAI. These are clinical syndromes based on clinical diagnosis which are currently managed arthroscopically upon failure of conservative treatment