The Dejour classification for trochlear dysplasia shows slight interobserver and substantial intraobserver reliability.

PURPOSE: Trochlear dysplasia is one of the main risk factors for recurrent patellar dislocation. The Dejour classification identifies four categories that can be used to classify trochlear dysplasia. The purpose of this study is to evaluate the inter- and intraobserver reliability of the Dejour classification for trochlear dysplasia. The hypothesis was that both intra- and interobserver reliability would be at least moderate. METHODS: This is a cross-sectional, reliability study. Twenty-eight examiners from the International Patellofemoral Study Group 2022 meeting evaluated lateral radiographs of the knee and axial magnetic resonance images from 15 cases of patellofemoral instability with trochlear dysplasia. They classified each case according to Dejour's classification for trochlear dysplasia (A-D). There were three rounds: one with only computed radiograph (CR), one with only magnetic resonance imaging (MRI) and one with both. Inter- and intraobserver reliability were calculated using κ coefficient (0-1). RESULTS: The mean age of patients was: 14.6 years; 60% were female and 53% had open physis. The interobserver reliability κ probabilities were 0.2 (CR), 0.13 (MRI) and 0.12 (CR and MRI). The intraobserver reliability κ probabilities were 0.45 (CR), 0.44 (MRI) and 0.65 (CR and MRI). CONCLUSION: The Dejour classification for trochlear dysplasia has slight interobserver reliability and substantial intraobserver reliability. LEVEL OF EVIDENCE: Level I.

SECEC Didier Patte Prize 2023: the ABC classification of posterior shoulder instability.

BACKGROUND: The ABC classification has recently been proposed as a comprehensive classification system for posterior shoulder instability (PSI). The purpose of this study was to analyze the comprehensiveness as well as inter-rater and intrarater reliability of the ABC classification. METHODS: All consecutive patients presenting with unidirectional PSI from June 2019 to June 2021 were included in a prospective study. No patients were excluded, leaving a consecutive series of 100 cases of PSI in 91 patients. All recorded clinical and imaging data were used to create anonymized clinical case vignettes, which were evaluated twice according to the ABC classification at the end of the recruitment period in random sequential order by 4 independent raters (2 experienced shoulder surgeons and 2 orthopedic residents) to analyze the comprehensiveness as well as inter-rater and intrarater reliability of the ABC classification for PSI and to describe differences in characteristics among subtypes. Group A was defined as a first-time singular PSI event <3 months in the past regardless of etiology and is further subdivided into type 1 and type 2 depending on the occurrence of a subluxation (A1) or dislocation (A2). Group B comprises recurrent dynamic PSI regardless of time since onset and is further subdivided by the cause of instability into functional (B1) and structural (B2) dynamic PSI. Group C includes chronic static PSI with posterior humeral decentering that can be either constitutional (C1) or acquired (C2). RESULTS: None of the cases was deemed unsuitable to be classified based on the proposed system by the observers. After consensus agreement between the 2 expert raters, 16 cases were attributed to group A (8 type A1 and 8 type A2); 64, to group B (33 type B1 and 31 type B2); and 20, to group C (11 type C1 and 9 type C2). The expert raters agreed on the classification subtypes in 99% and 96% of the cases during the first rating and second rating, respectively (intraclass correlation coefficients [ICCs], 0.998 and 0.99, respectively). The intraobserver reliability was excellent for both raters. The beginners reached the same conclusion as the consensus agreement in 94% of the cases (ICC, 0.99) and 89% of the cases (ICC, 0.97) during the first round and 94% each (ICC, 0.97) during the second round. The intraobserver reliability was excellent for both beginners. Overall, discrepancies between raters were found between groups B1 and B2 (n = 14), groups B2 and C2 (n = 4), groups B1 and C1 (n = 1), and groups A1 and B2 (n = 1). In general, each subtype showed distinctive clinical and imaging characteristics that facilitated the diagnosis. CONCLUSION: The presented ABC classification for PSI is a comprehensive classification with a high reliability and reproducibility. However, a gradual transition and potential progression between the subtypes of PSI must be considered. The reliable distinction between different subtypes of PSI based on etiology and pathomechanism provides a standardized basis for future investigations on treatment recommendations.

Development of a Core Set for Knee Dysfunction Based on the International Classification of Functioning, Disability and Health: A Cross-sectional Study.

OBJECTIVE: To develop an International Classification of Functioning, Disability and Health core set for patients with knee dysfunction. DESIGN: Cross-sectional study. SETTING: The study was conducted at all levels of care (general community, primary care units, rehabilitation clinics/centers, hospital). PARTICIPANTS: Participants (N=388) with knee dysfunction with or without clinical diagnosis of knee pathology, with or without complaint of pain, with or without instability, and/or with or without knee movement restriction of any type. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participants were assessed using the core sets for acute and postacute musculoskeletal conditions, the subjective form from the International Knee Documentation Committee scale, the self-report of general health and functionality, and the general health and functionality classified by the researcher. To identify the categories that best explain knee dysfunction, linear regression analyses were performed. RESULTS: Twenty-four categories were identified from the 75 core set categories for acute and postacute musculoskeletal conditions. Eleven categories belong to the component body functions, 3 represent body structures, 7 represent activities and participation, and 3 represent environmental factors. CONCLUSIONS: A core set for knee dysfunction that can be used at all levels of health care was proposed, which offers a system for disability assessment related to knee dysfunction, including environmental and social factors. These factors are important for a broad assessment because they include the multiple aspects of functionality, usually not considered in other knee dysfunction assessment instruments. Further analysis of the content and construct validity of the core set is required.

The Posterolateral Instability Score (PoLIS) of the knee joint: a guideline for standardized documentation, classification, and surgical decision-making.

PURPOSE: There has been a recent resurgence in interest in posterolateral instabilities of the knee joint. As this terminology comprises a large variety of pathologies, confusion and ambiguity in communication between surgeons and allied health professionals are generated. Consequently, accurate classification criteria are required to account for thorough preoperative diagnostics, surgical decision-making, and a standardized scientific documentation of injury severity. METHODS: A working group of five knee surgeons, who retrospect more than 2000 reconstructions of the posterolateral corner (PLC) at the minimum, was founded. An advanced PubMed search was conducted to identify key definitions. After defining an accurate diagnostic work-up, popular consensus was reached on definitions and covariates for a novel classification, rating of injury severity, and the resulting surgical decision-making. RESULTS: Three columns (lateral instability, cruciate ligament involvement, and relevant covariates), each ranging from A to D with increasing severity and assigning a number of points, were needed to meet the requirements. The generated terminology translated into the Posterolateral Instability Score (PoLIS) and the added number of points, ranging from 1 to 18, depicted the injury severity score. CONCLUSION: The presented classification may enable an objective assessment and documentation of the injury severity of the inherently complex pathology of injuries to the lateral side of the knee joint. LEVEL OF EVIDENCE: V.

Imaging evaluation of traumatic carpal instability.

PURPOSE: To review the epidemiology, pertinent wrist anatomy, classification system, and emergent imaging evaluation of carpal instability with a focus on radiographic assessment of instability. METHODS: A review of current literature on carpal instability was performed with summary presentation of carpal instability epidemiology, carpal anatomy, imaging evaluation, and classification with imaging evaluation focused on diagnosis in the emergency setting. RESULTS: Carpal instability is a common pathology in falls on outstretched hand and is likely underdiagnosed due to instability being occult or demonstrating subtle malalignment on static imaging of the wrist. While there is a complex network of intrinsic and extrinsic ligaments contributing to carpal instability, a detailed knowledge of these ligaments is not necessary for radiologists to make an accurate diagnosis in the emergency setting, as identification and classification of carpal instability is based on identification of carpal malalignment patterns on radiography as opposed to identification of specific ligament injuries on advanced imaging. The Mayo classification is the most widely used classification system, which divides carpal instability into four categories: dissociative, non-dissociative, complex, and adaptive. Understanding this classification system allows radiologists to successfully classify almost all carpal instability injuries they will encounter, even in the setting of unusual or rare instability patterns. CONCLUSION: In working with the treating clinician, it is essential that the emergency radiologist is comfortable with identifying and classifying carpal instability. This will ensure prompt treatment of seemingly benign injuries and those that require intervention, surgical or otherwise, improving the likelihood of a good outcome.

Comparison of functional outcomes among subtypes of Fraser's type â ¡ floating knee.

PURPOSE: The poor prognosis in patients with floating knee injuries is mainly contributed to articular involvement (Fraser's type Ⅱ). This study aims to evaluate and compare the functional outcomes among different Fraser's type Ⅱ floating knee injuries after surgical management. METHODS: Twenty-seven patients with Fraser's type Ⅱ floating knee injuries (54 fractures) between September 2014 and December 2015 were enrolled prospectively in this study and were distributed according to Fraser's floating knee classification into three different groups as type ⅡA (ipsilateral femoral shaft and tibial intra-articular involvement, n = 11), type ⅡB (ipsilateral tibial shaft and femoral intra-articular involvement, n = 9) and type ⅡC (both femoral and tibial intra-articular involvement, n = 7). The differences among the groups were evaluated and compared. The functional outcomes of these injuries at one year were analyzed using Knee Injury and Osteoarthritis Outcome Score (KOOS) which covers 5 subscales of pain, other symptoms, activities of daily living, sports and recreation, and quality of life. The result was also compared with standardized age-sex matched healthy population using paired samples t-test. RESULTS: All the patients were male, and the injury mechanism was solely roadside accident. The mean age was 29.8 years and injury severity score 17.9 (comparable in all the three groups). Most injuries were observed on the right side (20 cases, 74.1%). Based on paired samples t-test, the KOOS score of patients with Fraser's type ⅡA was found to be better than that of type ⅡB and type ⅡC. Compared with the reference age-sex matched control group, patients with Fraser's type ⅡB and ⅡC fractures had significantly lower mean score in all KOOS subscales (all p < 0.01). However, Fraser's type ⅡA only revealed significant difference regarding the subscales of activities of daily living (p < 0.0001), sports and recreation (p < 0.0001), and quality of life (p < 0.0001). CONCLUSION: The results of this study show that patients with Fraser's type ⅡA fractures had a better functional outcome as compared to those with type ⅡB and ⅡC fractures. This might be due to the open intra-articular involvement of the distal femur of the latter two fracture types.

Return to play after surgery for isolated unstable syndesmotic ankle injuries (West Point grade IIB and III) in 110 male professional football players: a retrospective cohort study.

OBJECTIVES: To evaluate time to return to play following surgical stabilisation of isolated unstable syndesmosis injuries in a cohort of professional male football players. METHODS: All professional football players undergoing surgery for isolated unstable syndesmosis injury (West Point grade ≥IIB) at a specialised Orthopaedic and Sports Medicine Hospital were followed up until return to play (minimum ≥6 months). Players with a stable syndesmosis, injuries older than 6 weeks, concomitant medial or lateral malleolar fracture or previous ankle surgery were excluded. During rehabilitation, time required to return to sports-specific rehabilitation, team training and first match play, were recorded. RESULTS: Between January 2012 and December 2017, a total of 110 male professional football players were included. The mean time required to begin on field rehabilitation was 37±12 days, while the mean time to return to team training was 72±28 days. The first official match was played on average 103±28 days postoperatively. Multivariable analysis revealed that the severity of injury, the concomitant presence of talar cartilage injury and the age of the player were significantly associated (p<0.00001) with time to return to on field rehabilitation, team training and match play. CONCLUSION: In this cohort of professional football players, surgical stabilisation of isolated unstable syndesmosis injuries (West Point grade ≥IIB) allowed for relatively quick return to play. High grade injury (West Point grade III), concomitant cartilage injury and greater age were associated with longer return to play times. LEVEL OF EVIDENCE: Longitudinal observational cohort study (level II).

Surgical outcomes in the Frequency, Etiology, Direction, and Severity (FEDS) classification system for shoulder instability.

BACKGROUND: The Frequency, Etiology, Direction, and Severity (FEDS) system was developed as a simple but reliable method for classifying shoulder instability based on 4 factors attainable by history and physical examination: frequency (solitary, occasional, or frequent); etiology (traumatic or atraumatic); direction (anterior, posterior, or inferior); and severity (subluxation or dislocation). This study investigated the epidemiology and 2-year surgical outcomes for the FEDS categories in the prospective Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort. METHODS: At the time of surgery, 1204 patients were assigned to the FEDS categories. Follow-up data were available for 636 of 734 patients (86.6%) who had undergone surgery at least 2 years prior to analysis. The most common categories were further analyzed by patient-reported outcomes (PROs) (American Shoulder and Elbow Surgeons, Western Ontario Shoulder Instability index, Single Assessment Numeric Evaluation scores) and rates of recurrent subluxation, recurrent dislocation, and revision surgery. RESULTS: Of the 36 FEDS categories, 16 represented at least 1% of patients. Occasional traumatic anterior dislocation (OTAD) was the most common category, with 16.4% of patients. Five other anterior categories (solitary traumatic anterior subluxation, occasional traumatic anterior subluxation [OTAS], frequent traumatic anterior subluxation [FTAS], solitary traumatic anterior dislocation, and frequent traumatic anterior dislocation) and one posterior category (solitary traumatic posterior subluxation [STPS]) represented at least 5% of patients. PROs improved significantly for each category. The highest rates of recurrent subluxation occurred in FTAS, OTAS, and OTAD cases; dislocation, OTAS and FTAS cases; and further surgery, OTAD cases. The lowest rates of failure occurred in STPS cases. Downward trends in PROs and higher failure rates were noted with an increasing number of preoperative dislocations. CONCLUSION: Different FEDS categories showed varying degrees of improvement and failure rates, indicating that the system can be used to provide prognostic insight for presurgical education. Overall, outcomes decreased with a higher number of preoperative dislocations.

Scoring system for optimal management of acute traumatic patellar dislocation: A multicenter study.

BACKGROUND: In first-time acute traumatic patellar dislocations, numerous anatomic and clinical factors are complicatedly associated and should be comprehensively considered for the optimal management of conservative or surgical intervention. The purpose of this study was to establish a scoring system, using a concept that is not complicated and easily used in clinic. METHODS: Of 131 first-time acute traumatic patellar dislocations, 81 patients (51 females, 30 males) with an average age of 19.6 (95%CI, 17.5-21.6) years and an average follow-up duration of 17.1 (95% CI, 12.3-21.9) months, who underwent conservative treatment after first-time dislocations, were reviewed. Based on the odds ratios applying logistic regression analysis, the scoring system was established. RESULTS: The scoring system (total: 10 points) had simple composition of age <20 (2 points), sports injury (1 points), hemarthrosis (1 points), and image findings of a bony fragment (3 points), lateral shift of the patella (1 points), and trochlear dysplasia (2 points). A threshold score of 6.5 was determined using the area under receiver operating characteristic curve of 0.893 (p < 0.0001). In logistic regression analysis, a score of ≥7 was shown to be a dominant factor for recurrence (OR = 27.1, p < 0.0001). Furthermore, the association between the score and recurrence risk was as follows: a score of ≤4 = low risk (1/21 cases, 5%); a score of 5-7 = medium risk (13/27 cases, 48%); a score of ≥8 = high risk (30/33 cases, 91%). CONCLUSIONS: Based on the simple scoring system, patients who scored ≥8 were considered suitable for surgical treatment because of the high rate of recurrence, whereas those who scored ≤4 were considered suitable for conservative treatment because of the low rate of recurrence.

Early stage and small medial osteochondral lesions of the talus in the presence of chronic lateral ankle instability: A retrospective study.

BACKGROUND: In chronic lateral ankle instability (CLAI), the instability of the ankle joint results in repeated microtrauma to the articular cartilage. How the lesion condition or stage is affected by the presence of lateral instability in medial osteochondral lesions of the talus (OLT) is unclear. We aimed to examine whether CLAI is associated with the size and staging of medial OLT on radiographs, magnetic resonance (MR) images, and arthroscopy. METHODS: Forty-five patients with medial OLTs in 45 ankles were reviewed. Radiographs were assessed for damage and lesion classification. The tibio-talar tilting angle (TTA) was measured. The patients were divided into two groups: the CLAI group and the stable group. The lesion classification on radiographs, MR images, and arthroscopy, and size on MR images were statistically compared. RESULTS: The CLAI group had a mean TTA of 8.15 ± 3.41°, whereas the stable group had a mean TTA of 2.24 ± 1.64°. The CLAI group had a lower clinical score than the stable group at the initial visit to our clinic. The CLAI group presented with lesions of significantly shorter longitudinal and transverse diameters. Stages of medial OLT on radiographs, MR images, and arthroscopic evaluation were earlier in the CLAI group than those in the stable group. CONCLUSIONS: Patients with CLAI presented in the early stages of OLT and had significantly smaller lesions than those without CLAI. The patients without CLAI may be selected for surgery at an early phase.

Joint hypermobility in children: a neglected sign needing more attention.

Joint hypermobility refers to the ability that a joint has to move beyond its normal range of motion. It is common in the general population, particularly in children. While many individuals manifesting joint hypermobility are healthy, this feature can accompany a wide range of symptoms and systemic disorders, whose management can be influenced by their prompt recognition. Given the increasing attention that joint hypermobility is attracting in various fields of medicine, many practitioners are asked to approach more carefully joint hypermobility, in order to avoid over- and under-diagnosis of related disorders. Among the most common conditions featuring joint hypermobility there are hypermobility spectrum disorders and hereditary connective tissue disorders, in particular, the Ehlers-Danlos syndromes. In children, joint hypermobility also accompany a variety of disorders affecting neurodevelopment. The nature of such an association is protean, as joint hypermobility may occur in selected congenital neuromuscular disorders, monogenic multiple malformation/intellectual disability syndromes, and well-known and emerging genomic syndromes. In addition, joint hypermobility seems strongly associated with developmental coordination disorders. This review offers an overview on definitions, assessment procedures, patterns of associated manifestations and disorders related to joint hypermobility, as well as treatment principles of associated musculoskeletal pain for practitioners that are not familial with this issue but encounter people featuring this physical attribute in their daily activity.

Severity classes in adults with hypermobile Ehlers-Danlos syndrome/hypermobility spectrum disorders: a pilot study of 105 Italian patients.

OBJECTIVES: This study is aimed at identifying discrete severity classes among adults with hypermobile Ehlers-Danlos syndrome (hEDS)/hypermobility spectrum disorders (HSD). METHODS: Subjects were selected according to the old and new nomenclatures and all completed a set of questionnaires exploring pain, fatigue, dysautonomic symptoms, coordination and attention/concentration deficits and quality of life in general. Data were investigated by hierarchical clustering on principal components. Cluster comparisons were then performed by using the two-sample unpaired t test and the standardized mean difference was reported as a measure of effect size. Conditional classification tree analysis and multivariable logistic regression were carried out in order to identify the profiles that were at higher risk to belong to the more severe cluster. Weighted linear combination was used to identify a numerical score measuring this risk. RESULTS: A total of 105 patients were selected and distributed in two distinct severity groups. These groups were statistically separated on the basis of 47 of 59 items/characteristics. One group featured the worse values of most questionnaire items (complex/severe cluster) and the other was dominated by the better values (simplex/milder cluster). Only three items were able to stratify patients according to their risk to belong to the complex cluster. A severity score was then constructed on these three items. CONCLUSION: Adults with hEDS/HSD can be separated in two severity classes, which do not mirror either the old or new criteria for hEDS. The identified severity score could allow a bi-dimensional approach to adults with hEDS/HSD for optimal management planning.

Grisel's Syndrome: Non-traumatic Atlantoaxial Rotatory Subluxation-Report of Five Cases and Review of the Literature.

BACKGROUND: In children, when unresponsive neck rigidity and distress are observed after ear, nose and throat (ENT) surgical treatment or nasopharyngeal inflammation, Grisel's syndrome should be suspected. This is a rare syndrome involving non-traumatic rotatory subluxation of the atlantoaxial joint. Conservative management with external cervical orthoses and empirical antibiotic, muscle relaxant and analgesic therapy should be the first choice of treatment. Surgical stabilization is indicated when high-grade instability or failure of stable reduction are observed. The instability is graded according to the classification system devised by Fielding and Hawkins. Several recommendations for treatment are available in the literature, but there are no common guidelines. In this paper, the authors discuss the need for prompt diagnosis and treatment considerations. CASE DESCRIPTION: Five children with Fielding type I-III rotatory subluxation are reported. Three patients were treated with a cervical collar, and one patient was treated with skull traction and sternal-occipital-mandibular immobilizer (SOMI) brace application. Surgical treatment was necessary for one patient after failure of initial conservative management. The intervals between the onset of torticollis and radiological diagnosis ranged from 12 to 90 days. A relationship between an increased grade of instability and delayed diagnosis was observed. CONCLUSION: In children with painful torticollis following ENT procedures or nasopharyngeal inflammation, Grisel's syndrome should always be suspected. Cervical magnetic resonance imaging (MRI) allows prompt and safe diagnosis, and a three-dimensional computed tomography (CT) scan provides better classification of the instability. Surgery, which is indicated in cases of high-grade instability or failure of conservative treatment, may be avoided with prompt diagnosis.

Epidemiology of the Frequency, Etiology, Direction, and Severity (FEDS) system for classifying glenohumeral instability.

HYPOTHESIS: The purpose of this multicenter epidemiologic study was to determine the distribution of patients within the Frequency, Etiology, Direction, and Severity (FEDS) classification system to determine which categories are of clinical importance. METHODS: Shoulder instability patients were identified using International Classification of Diseases, Ninth Revision coding data from 3 separate institutions from 2005-2010. Data were collected retrospectively. Details of instability were recorded in accordance with the FEDS classification system. Each patient was assigned a classification within the FEDS system. After all patients were assigned to a group, each group was individually analyzed and compared with the other groups. RESULTS: There are a total of 36 possible combinations within the FEDS system. Only 16 categories were represented by at least 1% of our patient population. Six categories captured at least 5% of all patients with shoulder instability. Only 2 categories represented greater than 10% of the population: solitary, traumatic, anterior dislocation, with 95 patients (24.8%), and occasional, traumatic, anterior dislocation, with 63 patients (16.4%). CONCLUSIONS: There are 16 categories within the FEDS classification that are clinically significant. Solitary, traumatic, anterior dislocation and occasional, traumatic, anterior dislocation were the most frequently observed in our cohort.

Effects of hyperbaric oxygen therapy on recovery acceleration in Japanese professional or semi-professional rugby players with grade 2 medial collateral ligament injury of the knee: A comparative non-randomized study.

INTRODUCTION: The effects of hyperbaric oxygen (HBO2) therapy on sprains, ligament injuries, and muscle strains have been reported in several animal studies. In a dog model of compartment syndrome and in a rat contused skeletal muscle injury model, the significant effects of HBO2 therapy on the reduction of edema and muscle necrosis have been reported. In basic research HBO2 therapy stimulated fibroblast activity to improve the healing process. Because of this it expected that HBO2 therapy might improve focal edema and pain in the acute phase and accelerate the healing of injured tissues in athletes with a medial collateral ligament (MCL) injury of the knee. This study aimed to examine the short-term effects of HBO2 application subjectively, and the long-term effects of HBO2 therapy in Japanese professional or semi-professional rugby players with grade 2 MCL injury of the knee. METHODS: Thirty-two professional or semi-professional rugby players with grade 2 MCL injury of the knee were investigated. First, in the HBO2 group (n=16), HBO2 therapy was performed during the acute phase. Visual analog scales (VASs) immediately before and after HBO2 therapy on the same day were compared. Next, we retrospectively evaluated the time to return to play in the HBO2 (n=16) and non-HBO2 (n=16) groups. RESULTS: VAS scores for pain while walking immediately before and after HBO2 therapy on the same day were 37.4 ± 20.1 (mean ± standard deviation) and 32.4 ± 21.8, respectively (p⟨0.001). The VAS scores for pain while jogging were 50.7 ± 25.6 and 43.9 ± 25.0, respectively (p⟨0.001). The time to return to play was 31.4 ± 12.2 days in the HBO2 group and 42.1 ± 15.8 days in the non-HBO2 group, indicating a significant difference between the groups (p⟨0.05). CONCLUSION: HBO2 therapy may reduce pain and accelerate the return to play in athletes with grade 2 MCL injury of the knee in this non-randomized study.

New quantitative radiographic parameters for vertical and horizontal instability in acromioclavicular joint dislocations.

PURPOSE: The aim of this study was to identify the most accurate and reliable quantitative radiographic parameters for assessing vertical and horizontal instability in different Rockwood grades of acromioclavicular joint (ACJ) separations. Furthermore, the effect of projectional variation on these parameters was investigated in obtaining lateral Alexander view radiographs. METHODS: A Sawbone model of a scapula with clavicle was mounted on a holding device, and acromioclavicular dislocations as per the Rockwood classification system were simulated with the addition of horizontal posterior displacement. Projectional variations for each injury type were performed by tilting/rotating the Sawbone construct in the coronal, sagittal or axial plane. Radiographic imaging in the form of an anterior-posterior Zanca view and a lateral Alexander view were taken for each injury type and each projectional variation. Five newly defined radiographic parameters for assessing horizontal and vertical displacement as well as commonly used coracoclavicular distance view were measured. Reliability, validity and the effect of projectional variation were investigated for these radiographic measurements. RESULTS: All radiographic parameters showed excellent intra- and interobserver reliability. The validity was excellent for the acromial centre line to dorsal clavicle (AC-DC) in vertical displacement and for the glenoid centre line to posterior clavicle (GC-PC) in horizontal displacement, whilst the remaining measurements showed moderate validity. For AC-DC and GC-PC, convergent validity expressed strong correlation to the effective distance and discriminant validity demonstrated its ability to differentiate between various grades of ACJ dislocations. The effect of projectional variation increased with the degree of deviation and was maximal (3 mm) for AC-DC in 20° anteverted malpositioning and for GC-PC in 20° retroverted malpositioning. CONCLUSIONS: AC-DC and the GC-PC are two novel quantitative radiographic parameters of vertical and horizontal instability in ACJ dislocations that demonstrate excellent reliability and validity with reasonable inertness to malpositioning. The use of AC-DC for assessing vertical displacement and GC-PC for assessing horizontal displacement in a single Alexander view is recommended to guide the appropriate management of ACJ dislocations. A better appreciation of the degree of horizontal instability, especially in lower Rockwood grades (II, III) of ACJ dislocations, may improve management of these controversial injuries.

Force Required to Maintain Reduction of a Preexisting Scapholunate Dissociation.

PURPOSE: To determine the force required to maintain reduction of Geissler grade 4 scapholunate dissociations during physiological wrist motions. METHODS: Fresh-frozen cadaveric wrists with Geissler grade 4 scapholunate dissociations were identified by arthroscopy. Following reduction, a load cell was attached to measure the force across the scapholunate joint at a neutral position and during 4 different wrist motions re-created using a servohydraulic wrist simulator, including a large flexion-extension motion (FEM), small and large dart-thrower's motions (DTMs), and a large DTM with ulnar offset. RESULTS: Five wrists with isolated preexisting scapholunate interosseous ligament (SLIL) tears were analyzed. The force required to maintain reduction was significantly greater in extension than in flexion during the large FEM and large DTM with ulnar offset. The forces were significantly larger in this study of preexisting SLIL dissociations compared with results from a prior study of acutely sectioned SLILs. In addition, forces to maintain reduction during DTMs were significantly less than forces during FEMs. Finally, a set of 3 wrists with preexisting scapholunate and lunotriquetral interosseous ligament (LTIL) tears were identified and had significantly decreased forces to maintain reduction at maximum extension and had decreased maximal forces during a cycle of motion compared with the wrists with isolated SLIL tears. CONCLUSIONS: The forces required to maintain reduction of a Geissler grade 4 wrist are higher than forces after acutely sectioned SLIL. The forces are greater in extension than in flexion and less during the DTM compared with the FEM. Wrists with both SLIL and LTIL tears required less force to maintain reduction than those with isolated SLIL tears. CLINICAL RELEVANCE: This study helps determine the strength of reconstruction required to maintain reduction of a Geissler grade 4 scapholunate dissociation.

Classification of instability after reverse shoulder arthroplasty guides surgical management and outcomes.

BACKGROUND: Revision of unstable reverse shoulder arthroplasty (RSA) remains a significant challenge. The purpose of this study was to determine the reliability of a new treatment-guiding classification for instability after RSA, to describe the clinical outcomes of patients stabilized operatively, and to identify those with higher risk of recurrence. METHODS: All patients undergoing revision for instability after RSA were identified at our institution. Demographic, clinical, radiographic, and intraoperative data were collected. A classification was developed using all identified causes of instability after RSA and allocating them to 1 of 3 defined treatment-guiding categories. Eight surgeons reviewed all data and applied the classification scheme to each case. Interobserver and intraobserver reliability was used to evaluate the classification scheme. Preoperative clinical outcomes were compared with final follow-up in stabilized shoulders. RESULTS: Forty-three revision cases in 34 patients met the inclusion for study. Five patients remained unstable after revision. Persistent instability most commonly occurred in persistent deltoid dysfunction and postoperative acromial fractures but also in 1 case of soft tissue impingement. Twenty-one patients remained stable at minimum 2 years of follow-up and had significant improvement of clinical outcome scores and range of motion. Reliability of the classification scheme showed substantial and almost perfect interobserver and intraobserver agreement among all the participants (κ = 0.699 and κ = 0.851, respectively). DISCUSSION: Instability after RSA can be successfully treated with revision surgery using the reliable treatment-guiding classification scheme presented herein. However, more understanding is needed for patients with greater risk of recurrent instability after revision surgery.

[Current aspects and new techniques in dislocation of the shoulder joint]. / Aktuelle Aspekte und neue Techniken bei Schultereckgelenksprengung.

With 12% of all injuries concerning the shoulder, acromioclavicular (AC) joint dislocations are a common injury especially in young and active patients. The Rockwood classification is widely accepted, which differentiates between six types depending on the degree of injury and the vertical dislocation. Because the classification does not adequately address the horizontal instability, its benefits are questionable and there is currently no consensus. For this reason, the classification and the therapy of these injuries are increasingly becoming the subject of scientific investigations. Whereas conservative treatment for type I and II injuries and operative treatment for type IV-VI injuries are widely accepted, there is still no agreement in treating type III lesions. The goal of this review article is to present the current evidence for the diagnostics, different classifications and therapeutic possibilities.

[The ABC guide for the treatment of posterior shoulder instability]. / Das ABC der posterioren Schulterstabilisierung.

BACKGROUND: Posterior glenohumeral instability (PGHI) is an often unrecognized or misdiagnosed type of shoulder instability due to its heterogenic clinical and radiological presentation. CLASSIFICATION: The ABC classification for PGHI is based on the different pathomechanisms and recommended treatment standards and is therefore a guide to finding the correct diagnosis and therapy for affected patients. There are different types of PGHI: A (first time), B (dynamic), C (static). These groups are further classified based on pathomechanical principles: A1: subluxation, A2: dislocation; B1: functional, B2: structural; C1: constitutional, C2: acquired. THERAPY: In patients with type 1 PGHI (A1, B1, C1) conservative treatment is recommended while in patients with type 2 PGHI (A2, B2, C2) surgical treatment can be considered based on structural defects, clinical symptoms, chronicity, age, functional demand, and patient-specific health status. In addition it has to be considered, that there is the possibility of coexisting or overlapping subtypes as well as the chance of progression from one category into another over time.