Semiquantitative index of symptomatic minor instability of the lateral elbow at CT arthrography (SMILE index): clinical applicability and reproducibility study.

OBJECTIVE: To assess the applicability of a semiquantitative index for symptomatic minor instability of the lateral elbow (SMILE). MATERIALS AND METHODS: CT arthrograms of consecutive patients with lateral elbow pain who underwent ultrasound-guided CT arthrography at our orthopedic center between April 2019 and May 2022 were included. Images were acquired at 100 kVp and 80 mAs. An expert radiologist (R1) and a radiology resident (R2) retrospectively performed an independent, blinded evaluation of the arthrograms to assess the presence of imaging findings suggestive of elbow instability. The SMILE index (0-8) was obtained adding (I) radial head chondromalacia (0 - 1); (II) humeral capitellum chondromalacia (0 - 1); (III) humeral trochlear ridge chondromalacia (0 - 1); (IV) annular ligament laxity (0 - 2); (V) synovial thickening (0 - 1); (VI) humeroradial joint asymmetry (0 - 1); and (VII) capsular tear (0 - 1). R1 repeated the assessment after 14 days. Cohen's weighted κ statistic and raw concordance were used to appraise reproducibility. RESULTS: Eighty patients (median age 49 years, interquartile range 40-53 years, 49, 61% males) underwent CT arthrography at our center, and 10 (12%) of them underwent bilateral elbow examination, leading to 90 included CT arthrograms. Median SMILE index was 4 (IQR: 2-5) for R1, 4 (IQR: 2-5) for R2, and 4 (IQR: 2-5) for the second assessment by R1. Intra-reader agreement was excellent (κ = 0.94, concordance 87%), while inter-reader agreement was substantial (κ = 0.75, concordance 67%). CONCLUSION: The proposed SMILE index showed good reproducibility; further studies are warranted to correlate our index with clinical and surgical data. CLINICAL RELEVANCE STATEMENT: Our scoring system allows a standardized evaluation of patients with lateral elbow pain and instability suitable for application into clinical practice, complementing the orthopedic surgeon's clinical diagnosis with imaging findings that may aid treatment choices. KEY POINTS: • Lateral elbow pain is often interpreted clinically as lateral epicondylitis, but it can also encompass intra-articular pathology. • The proposed arthrographic index allows comprehensive quantification of lateral elbow pathology with good reproducibility and application times. • Our index provides the orthopedic surgeon with information regarding intra-articular findings, aiding treatment choices.

A low carrying angle is measured in elite tennis players just before ball impact during the forehand, suggesting a dynamic varus instant accommodation moving towards full extension.

PURPOSE: The goal of this study was to use image analysis recordings to measure the carrying angle of elite male tennis players during the forehand stroke, with the hypothesis that elite tennis players overstress their elbow in valgus over the physiological degree in the frontal plane just before ball contact on forehand groundstrokes. METHODS: The carrying angle of male tennis players ranked in the top 25 positions in the ATP ranking was measured on selected video frames with the elbow as close as possible to full extension just before the ball-racket contact in forehands. These frames were extracted from 306 videos professionally recorded for training purposes by a high-profile video analyst. All measures were conducted by three independent observers. RESULTS: Sixteen frames were finally included. The mean carrying angle was 11.5° ± 4.7°. The intraclass correlation coefficient value was 0.703, showing good reliability of the measurement technique. The measured carrying angle was lower than what has been observed in historical cohorts using comparable measurement methodology, suggesting a possible instant varus accommodation mechanism before hitting the ball. CONCLUSIONS: The observed decrease in the carrying angle is a consequence of an increase in elbow flexion position dictated by the transition from a closed to open, semi-open stances. As the elbow flexes during the preparation phase, it is less constrained by the olecranon and its fossa, increasing the strain on the medial collateral ligament and capsule structures. Moving towards full extension before the ball-racket contact, the elbow is dynamically stabilised by a contraction of the flexor muscles. These observations could provide a new explanation for medial elbow injuries among elite tennis players and drive specific rehabilitation protocols. STUDY DESIGN: Descriptive epidemiology study. LEVEL OF EVIDENCE: Level IV.

Proximal radioulnar joint, but not posterolateral, instability in patients with symptomatic minor instability of the lateral elbow.

BACKGROUND: The elbow joint is stabilized laterally by a complex of bony and ligamentous structures, such as the lateral ulnar collateral ligament and radial lateral collateral ligament (RLCL). Pathogenesis of many elbow conditions like symptomatic minor instability of the lateral elbow (SMILE) is based on ligamentous incompetency. The aim of this study is to measure ligament elongation in SMILE patients and determine the correlation with the development of this pathologic condition. MATERIALS AND METHODS: Twenty-eight patients were included in this study: half of them were operated for suspected SMILE whereas the others were affected by other elbow diseases. All the patients underwent elbow arthroscopy. During this procedure, 4 parameters were analyzed: annular drive through (ADT), ulnar-humeral stressed distance (UHSD) at 45° and 30° of flexion, and loose collar sign (LCS). A dedicated arthroscopic mini-spreader introduced through an arthroscopic portal was used to take measurements. RESULTS: Statistically significant differences were found for LCS (P = .0003) and ADT (P = .000002). UHSD at 30° and 45° elbow flexion was slightly higher in SMILE patients, but not significantly. DISCUSSION AND CONCLUSIONS: Progressive stretching of the RLCL and annular ligament may lead to their elongation, resulting in a pathologic anteroposterior shifting of the radial head and a lower congruence between the inner surface of the annular ligament and the radial head cartilage, resulting in proximal radioulnar instability. The study shows how RLCL and annular ligament are elongated in SMILE patients compared with controls, causing instability of the proximal radioulnar joint and confirming that ligament incompetency is involved in the SMILE condition.

Look for the POLESTAR (POsteroLateral Engagement of Soft Tissue And Radial head) while navigating around elbow dislocation.

BACKGROUND: Elbow dislocation is frequently associated with bony and osteochondral posterolateral capitellar lesions that are often under-reported. We aim to examine the radiologic signs of posterolateral lesions on computed tomography (CT). METHODS: A retrospective analysis of CT scans was performed. Patients were classified into 4 groups: (1) simple elbow dislocation, (2) elbow dislocation with a fracture of the coronoid tip, (3) elbow dislocation with coronoid tip fracture and a radial head fracture inferior or equal to the anterior third, and (4) terrible triad defined as elbow dislocation with concomitant coronoid and radial head fracture with a more important involvement. Patients with a more complex fracture pattern were excluded. The presence of POsteroLateral Engagement of Soft Tissue And Radial head (POLESTAR) patterns was analyzed and subclassified as impaction type or fragmentation type. RESULTS: Fifty-one CT scans met the inclusion criteria. POLESTAR lesions were identified in 48 cases (94%): 46% impaction-type and 54% fragmentation-type POLESTAR. Analyzing patients from grade 1 to 4, impaction-type POLESTAR was found, respectively, from 40% to 57%, whereas fragmentation type was present from 60% to 43%. CONCLUSIONS: This study shows a high incidence of POLESTAR lesions (94%) that can be present as impaction type or fragmentation type. Based on our preliminary results, impaction type is more common in grades 3 and 4, whereas fragmentation type is more frequent in grades 1 and 2.

Anatomic relations of the median nerve to the ulnar insertion of the brachialis muscle: safety issues and implications for medial approaches to the elbow joint.

INTRODUCTION: Preventing nerve injury is critical in elbow surgery. Distal extension of medial approaches, required for coronoid fracture fixation and graft-replacement, may endanger the median nerve. This study aims to describe an easily identifiable and reproducible anatomical landmark to localize the median nerve distal to the joint line and to delineate how its relative position changes with elbow flexion and forearm rotation. MATERIALS AND METHODS: The median nerve and the ulnar insertion of the brachialis muscle were identified in eleven fresh-frozen cadaveric specimens after dissection over an extended medial approach. The elbow was brought first in full extension and then in 90° flexion, and the shortest distance between the two structures was measured while rotating the forearm in full pronation, neutral position and full supination. RESULTS: The distance between the median nerve and the brachialis insertion was highest with the elbow flexed and the forearm in neutral position. All distances measured in flexion were larger than those in extension, and all distances measured from the most proximal point of the brachialis insertion were larger than those from the most distal point. Distances in pronation and in supination were smaller than to those in neutral forearm position. CONCLUSIONS: The ulnar insertion of the brachialis is a reliable landmark to localize and protect the median nerve at the level of the coronoid base. Elbow flexion and neutral forearm position increase significantly the safety margins between the two structures; this information suggests some modifications to the previously described medial elbow approaches. LEVEL OF EVIDENCE: Basic Science Study.

Ultrasound evaluation shows increase in laxity after partial common extensor origin detachment but not after additional lesion of the radial band of the lateral collateral ligament.

PURPOSE: The lateral elbow musculature conveys a dynamic valgus moment to the elbow, increasing joint stability. Muscular or tendinous lesions to the anterior half of the common extensor origin (CEO) may provoke a deficiency in the elbow dynamic stabilizers, regardless of their traumatic, degenerative, or iatrogenic aetiology. Furthermore, a role for the radial band of the lateral collateral ligament (R-LCL) has been postulated in the aetiology of lateral elbow pain. This study aimed to evaluate the effects of sequential lateral releases with dynamic ultrasound, evaluating its capability to detect lesions of the CEO and of the R-LCL. METHODS: Ultrasound investigation of the lateral compartment of the elbow was performed on nine cadaveric specimens with a 10 MHz linear probe in basal conditions, after the release of the anterior half of the CEO and after complete R-LCL release. The lateral joint line widening (λ) was the primary outcome parameter, measured as the linear distance between the humeral and radial articular surfaces. RESULTS: The release of the anterior half of the CEO significantly increased λ by 200% compared to the starting position (p = 0.0008) and the previously loaded position (p = 0.0015). Conversely, further release of the R-LCL caused only a marginal, non-significant increase in λ. CONCLUSIONS: Ultrasound evaluation can detect changes related to tendon tears or muscular avulsions of the CEO and can depict lateral elbow compartmental patholaxity by assessing articular space widening while scanning under dynamic stress. However, it cannot reliably define if the R-LCL is injured. Iatrogenic damage to the CEO should be carefully avoided, since it causes a massive increase in compartmental laxity.

No neurovascular damage after creation of an accessory anteromedial portal for arthroscopic reduction and fixation of coronoid fractures.

PURPOSE: Arthroscopic reduction and internal fixation for coronoid process fractures has been proposed to overcome limitations of open approaches. Currently, arthroscopy is most frequently used to assist insertion of a retrograde guide wire for a retrograde cannulated screw. The present anatomical study presents an innovative arthroscopic technique to introduce an antegrade guide wire from an accessory anteromedial portal and evaluates its safety and reproducibility. METHODS: Six fresh-frozen cadaver specimens were obtained and prepared to mimic an arthroscopic setting. The coronoid process was localized and a 0.9 mm Kirschner wire was introduced from an accessory anteromedial portal, located 2 cm proximal to the standard anteromedial portal. At the end of the procedure, a lateral radiograph was taken to verify the Kirschner wire position and open dissection was conducted to evaluate possible damage to neurovascular structures. RESULTS: The Kirschner wire was drilled without complications in the coronoid process of all six specimens. Damage of the brachial artery, the median nerve, and the ulnar nerve did not occur in any specimen. A corridor between the brachialis muscle, the median intermuscular septum, and the pronator teres could be identified as suitable for the wire passage. CONCLUSION: This study presents a safe and reproducible technique combining the possibility to introduce a guide wire from the anteromedial part of the coronoid, under direct visual control, with a completely arthroscopic approach. This wire can guide the introduction of a retrograde cannulated screw from the dorsolateral ulna to the tip of the coronoid. This new arthroscopic approach permits to obtain improved visual control over coronoid process fixation, without endangering neurovascular structures.

Locating the ulnar nerve during elbow arthroscopy using palpation is only accurate proximal to the medial epicondyle.

PURPOSE: Knowledge of ulnar nerve position is of utmost importance to avoid iatrogenic injury in elbow arthroscopy. The aim of this study was to determine how accurate surgeons are in locating the ulnar nerve after fluid extravasation has already occurred, and basing their localization solely on palpation of anatomical landmarks. METHODS: Seven cadaveric elbows were used and seven experienced surgeons in elbow arthroscopy participated. An arthroscopic setting was simulated and fluids were pumped into the joint from the posterior compartment for 15 min. For each cadaveric elbow, one surgeon was asked to locate the ulnar nerve solely by palpation of the anatomical landmarks, and subsequently pin the ulnar nerve at two positions: within 5 cm proximal and another within 5 cm distal of a line connecting the medial epicondyle and the tip of the olecranon. Subsequently, the elbows were dissected using a standard medial elbow approach and the distances between the pins and ulnar nerve were measured. RESULTS: The median distance between the ulnar nerve and the proximal pins was 0 mm (range 0-0 mm), and between the ulnar nerve and the distal pins was 2 mm (range 0-10 mm), showing a statistically significant difference (p = 0.009). All seven proximally placed pins (100%) transfixed the ulnar nerve versus two out of seven distally placed pins (29%) (p = 0.021). CONCLUSIONS: In a setting simulating an already initiated arthroscopic procedure, the sole palpation of the anatomical landmarks allows experienced elbow surgeons to accurately locate the ulnar nerve only in its course proximal to the medial epicondyle (7/7, 100%), whereas a significantly reduced accuracy is documented when the same surgeons attempt to locate the nerve distal to the medial epicondyle (2/7, 29%; p = 0.021). Current findings support the establishment of a proximal anteromedial portal over a distal anteromedial portal to access the anterior compartment after tissue extravasation has occurred with regard to ulnar nerve safety.

A combination of an anteromedial, anterolateral and midlateral portals is sufficient for 360° exposure of the radial head for arthroscopic fracture fixation.

PURPOSE: Arthroscopic fixation of radial head fractures is an alternative to open reduction and internal fixation; the latter, however, presents the advantage of minimal soft-tissue damage. The exposure of the radial head for adequate screw placement can be technically challenging. The aim of this study was to evaluate the inter-observer agreement on the effective contact arc in the axial plane of the radial head of three different elbow arthroscopy portals. METHODS: A fresh-frozen cadaver specimen was obtained and prepared in an arthroscopic setting. Standard anterolateral (AL), anteromedial (AM), and midlateral (ML) portals were established and a circular reference system was marked on the radial head. Ten orthopaedic surgeons were then asked to move the forearm from maximal supination to maximal pronation and indicate with a Kirschner wire from each portal the extension in which they would feel confident in placing a cannulated screw passing through the centre of the articular plane of the radial head (axial contact arc). The Shapiro-Wilk normality test was used to evaluate the normal distribution of the sample. A coefficient of variation (CoV) was calculated to determine agreement among observers. RESULTS: The average arc of axial contact arc that could be contacted from the AM portal measured 150 ± 14.1°, or 41.7% of the radial head circumference; the one from the AL portal measured 257 ± 29.5°, or 71.4% of the radial head circumference; that from the ML portal measured 212.5 ± 32.6°, or 59.0% of the radial head circumference. Considering all three portals, the whole radial head circumference could be contacted. The AM portal showed the smallest CoV (9.4%) as compared to the AL (11.5%), and the ML (15.3%) portals. CONCLUSIONS: With an appropriate use of the standard AL, AM, and ML portals, the whole radial head circumference can be effectively exposed for adequate fixation of radial head fractures. The contact arc of the AM portal presents the smallest variability among different observers and the AL portal shows a superiority in axial contact arc. This information is important for pre-operative planning, and helps to define the limits of arthroscopic radial head fracture fixation.

Modified anteromedial and anterolateral elbow arthroscopy portals show superiority to standard portals in guiding arthroscopic radial head screw fixation.

PURPOSE: Arthroscopic fixation of radial head radial head fractures is an appealing alternative to open reduction and internal fixation, which presents the advantage of minimal surgical trauma. The aim of this study was to evaluate if modifications to the standard anteromedial (AM) and anterolateral (AL) portals could allow screw placement for radial head fracture osteosynthesis closer to the plane of the radial head articular surface. METHODS: Eight fresh-frozen specimens were prepared to mimic arthroscopic setting. Standard AL (ALst) and AM (AMst) and distal AL (ALdi) and AM (AMdi) portals were established. Eleven independent examiners were asked to indicate the optimal trajectory, when aiming to place a cannulated screw parallel to the radial head surface for radial head osteosynthesis. A three-dimensional digital protractor was used to measure the angle between the indicated position and a Kirschner wire placed parallel to the radial head articular surface (α). The Shapiro-Wilk normality test was used to evaluate the normal distribution of the samples. Means, standard deviations, and 95% confidence intervals (95% CI) were calculated for each portal. A coefficient of variation (CoV) was calculated to determine agreement among observers and intra-observer variability. RESULTS: Mean α angles were 25.1 ± 11.5° for AMst, 13.8 ± 4.8° for AMdi, 17.1 ± 13.4° for ALst, -2.6 ± 9.2° for ALdi. No overlapping in the 95% CI of ipsilateral standard and distal portals was observed, indicating that the difference between these means was statistically significant. The distal portals showed smaller inter-observer CoV as compared to the standard ones (AMst: 10.0%; AMdi: 4.6%; ALst: 12.5%; ALdi: 10.6%). Intra-observer CoV was similar for all portals (AMst: 5.5%; AMdi: 6.1%; ALst: 7.7%; ALdi: 7.1%). CONCLUSIONS: The use of distal AM and AL portals permits to obtain α angles closer to the radial head articular surface than standard AM and AL portals. This is expected to allow screw placement in a flatter trajectory, which should correlate with a superior biomechanical performance of fixation. Good reproducibility of Kirschner wire placement from distal portals was observer among different examiners. Modifications to the standard AM and AL elbow arthroscopy portals allow to place screws for radial head fracture osteosynthesis in a position which should guarantee superior biomechanical performance of fixation.

The posterior interosseous nerve crosses the radial head midline and increases its distance from bony structures with supination of the forearm.

BACKGROUND: This study investigated whether forearm movements change the relative position of the posterior interosseous nerve (PIN) with respect to the midline of the radial head (Rh) under direct arthroscopic observation. METHODS: The PIN was identified in 10 fresh frozen cadaveric specimens dissected under arthroscopy. The forearm was moved first in full pronation and then in full supination, and the displacement of the PIN from medial to lateral with respect to the midline of the Rh was recorded. The shortest linear distance between the nerve and the most anterior part of the Rh was measured with a graduated calliper inserted via the midlateral portal with the forearm in neutral position, full pronation, and full supination. RESULTS: The PIN was identifiable in all specimens. In all cases the PIN crossed the Rh midline with forearm movements, moving from medial in full pronation to lateral in full supination. The distance between the PIN and Rh is significantly greater in supination than in the neutral position and pronation (P = .0001). CONCLUSIONS: This study confirms that the PIN movement described in open surgery (medialization with pronation) also occurs during arthroscopy. The role of pronation in protecting the PIN in extra-articularprocedures is therefore confirmed. Supination, however, increases the linear distance between the PIN and Rh and should therefore be considered to increase the safe working volume whenever intra-articular procedures are performed on the anterolateral aspect of the elbow.

Translation, cross-cultural adaptation, and validation of the Italian version of the Oxford Shoulder Instability Score.

PURPOSE: The Oxford Shoulder Instability Score (OSIS) is self-reported outcome measurement developed to evaluate shoulder instability taking into account also adaptive strategies. Valid, reliable, reproducible, and user-friendly translations of outcome measure instruments are needed to allow comparisons of international study results. METHODS: The Italian translation and cultural adaptation of the OSIS were completed using a "translation-back translation" method and the final version was administered to a sample of 25 consecutive Italian-speaking patients. The psychometric properties of this adaptation were evaluated in terms of feasibility, reliability, construct validity, and responsiveness. RESULTS: No major differences occurred between the OSIS translations into Italian and back into English, and no content- or linguistic-related difficulties were reported. The Cronbach's alpha for the total OSIS was 0.897. Intraclass correlation coefficient value for inter-rater reliability was 0.805, while for intra-rater reliability was 0.586. Spearman rank correlation coefficient between the OSIS and the Rowe score was 0.548 (p = 0.005) and between OSIS-I and SF-12 was 0.488 (p = 0.013). CONCLUSIONS: The Italian version of the OSIS is a reliable, valid, and reproducible outcome measure for clinical evaluation of patients affected by shoulder instability, which remains simple and user-friendly as the original version. LEVEL OF EVIDENCE: Prospective cohort study, Level II. CLINICAL RELEVANCE: The availability of a validated translation of the OSIS will help surgeon to share their data on shoulder instability diagnostic and treatment in a more reproducible and comparable fashion.

Level of the Subscapularis Split During Arthroscopic Latarjet.

PURPOSE: To determine the location of the subscapularis split during arthroscopic Latarjet created by an inside-out technique passing a switching stick from the posterior portal across the glenohumeral joint. METHODS: An inside-out technique was used to arthroscopically create a subscapularis split in 20 fresh-frozen human cadaveric shoulders. The distance between the exit point of the switching stick and the upper border of the subscapularis and the anterior circumflex vessels was measured arthroscopically and after open dissection. RESULTS: Twelve splits were in the upper third of the subscapularis, 3 were at the junction of the upper third and the middle third, and 5 were in the middle third. None were at the junction between the middle and lower third as desired. CONCLUSIONS: Using the inside-out method during arthroscopic Latarjet may produce a high subscapularis split if it is performed from with a switching stick that is inserted through the posterior approach, and passed across the glenohumeral joint at the level of the inferior glenoid. CLINICAL RELEVANCE: This study analyzed the relative risk of high subscapularis split during the arthroscopic Latarjet procedure.

Arthroscopic R-LCL plication for symptomatic minor instability of the lateral elbow (SMILE).

PURPOSE: Minor instability has been proposed as a possible aetiology of lateral elbow pain. This study presents the results of the arthroscopic plication of the radial component of the lateral collateral ligament (R-LCL) to reduce minor instability of the lateral elbow. METHODS: Twenty-seven patients with recalcitrant lateral epicondylitis who had failed conservative therapy and who had no previous trauma or overt instability, were included. R-LCL plication was performed in the presence of at least one sign of lateral ligamentous patholaxity and one intra-articular abnormal finding. Single-assessment numeric evaluation (SANE), Oxford Elbow Score (OES), quickDASH (Disabilities of the Arm, Shoulder, Hand), patient satisfaction and post-operative range of motion were evaluated. RESULTS: SANE improved from a median of 30 [2-40] points pre-operatively to 90 [80-100] at final follow-up (p < 0.0001), and 96.3% patients obtained good or excellent subjective results. Post-operative median quickDASH was 9.1 [0-25] points and OES 42 [34-48]. Median post-operative flexion was 145°, and extension was 0°. Post-operative flexion was restrained in seven patients and extension in eight patients; 59% of patients reached full ROM at final follow-up. CONCLUSIONS: R-LCL plication produces subjective satisfaction and positive clinical results in patients presenting with a symptomatic minor instability of the lateral elbow (SMILE) at 2-year median follow-up. A slight limitation in range of motion is a possible undesired consequence of this intervention. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Intra-articular findings in symptomatic minor instability of the lateral elbow (SMILE).

PURPOSE: Lateral epicondylitis is generally considered an extra-articular condition. The role of minor instability in the aetiology of lateral elbow pain has rarely been considered. The aim of this study was to evaluate the correlation of lateral ligamentous laxity with aspects of intra-articular lateral elbow pathology and investigate the role of minor instability in lateral elbow pain. METHODS: Thirty-five consecutive patients aged between 20 and 60 years with recalcitrant lateral epicondylitis who had failed conservative therapy and had no previous trauma or overt instability, were included. The presence of three signs of lateral ligamentous patholaxity and five intra-articular findings were documented during arthroscopy. The relative incidence of each of these was calculated, and the correlation between patholaxity and intra-articular pathology was evaluated. RESULTS: At least one sign of lateral ligamentous laxity was observed in 48.6% of the studied cohort, and 85.7% demonstrated at least one intra-articular abnormal finding. Radial head ballottement was the most common sign of patholaxity (42.9%). Synovitis was the most common intra-articular aspect of pathology (77.1%), followed by lateral capitellar chondropathy (40.0%). A significant correlation was found between the presence of lateral ligamentous patholaxity signs and capitellar chondropathy (p = 0.0409), as well as anteromedial synovitis (p = 0.0408). CONCLUSIONS: Almost one half of patients suffering from recalcitrant lateral epicondylitis display signs of lateral ligamentous patholaxity, and over 85% demonstrate at least one intra-articular abnormality. The most frequent intra-articular findings are synovitis and lateral capitellar chondropathy, which correlate significantly with the presence of lateral ligamentous patholaxity. The fact that several patients demonstrated multiple intra-articular findings in relation to laxity provides support to a sequence of pathologic changes that may result from a symptomatic minor instability of the lateral elbow (SMILE) condition. LEVEL OF EVIDENCE: III.

The anterior borders of the clavicle and the acromion are not always aligned in the intact acromioclavicular joint: a cadaveric study.

BACKGROUND: The aim of this study was to find reliable anatomic landmarks of the normal acromioclavicular joint (ACJ) that could enable the precise evaluation of the horizontal displacement of the clavicle after dislocation. The hypothesis was that the anterior borders of the acromion and the clavicle are always aligned in intact ACJs. MATERIALS AND METHODS: In 30 cadaveric specimens, the anterior and posterior borders of the ACJ's articular facets and the most prominent anterior and posterior bony landmarks of the acromion and the clavicle were identified. The anterior and posterior overhang of the acromion and the clavicle was measured in relation to the borders of the articular facets. Therefore, the possible anterior and posterior alignment of the ACJ was evaluated. RESULTS: Anteriorly, only 18 ACJs (60%) were aligned whereas 7 (24%) had major overhang of the acromion and 3 (10%) had major overhang of the clavicle. Similarly, 18 cases (60%) were posteriorly aligned, whereas 6 (20%) had major clavicular overhang and 4 (14%) had major overhang of the acromion. In 78% of these cases, the ACJ was aligned as well anteriorly as posteriorly (P < .001). Finally, the larger the width of the acromion (P = .032) or the clavicle (P = .049), the better the posterior joint alignment. CONCLUSION: Our hypothesis was not verified. The acromion and clavicle are not perfectly aligned in a significant number of specimens with intact ACJs (40% of cases). The most reliable landmarks remain their articular facets.

Is arthroscopic remplissage a tenodesis or capsulomyodesis? An anatomic study.

PURPOSE: Arthroscopic remplissage of a Hill-Sachs lesion is classically described as a capsulotenodesis of the infraspinatus within the posterolateral humeral head. The aim of this cadaveric study was to evaluate the anatomic relationship between the position of anchors and sutures placed for remplissage and the infraspinatus and teres minor. The hypothesis was that remplissage actually corresponds to a capsulomyodesis of the infraspinatus and teres minor muscles. METHODS: A two-anchor arthroscopic remplissage was performed followed by open dissection of ten fresh-frozen human cadaveric shoulders. The exit point of sutures related to muscle-tendon unit as well as the distance between the anchors and the rotator cuff was measured. RESULTS: The superior sutures were localized generally in the infraspinatus, near the musculotendinous junction. The inferior sutures passed through the teres minor muscle in seven of ten cases. The distance between the superior and inferior anchors and the posterolateral greater tuberosity was 14 ± 2 and 12 ± 3 mm, respectively. CONCLUSIONS: Arthroscopic remplissage is a capsulomyodesis of infraspinatus and teres minor rather than a capsulotenodesis of the infraspinatus alone as previously believed. Muscular damage may explain posterosuperior pain observed in patients who underwent remplissage.

Arthroscopic proximal biceps tenodesis at the articular margin: evaluation of outcomes, complications, and revision rate.

PURPOSE: The purpose of this study was to evaluate the incidence of residual pain, outcomes, and the revision rate of arthroscopic proximal biceps tenodesis high in the groove at the articular margin of the humeral head by interference screw fixation. METHODS: Seven surgeons pooled data on patients who underwent an arthroscopic biceps tenodesis at the articular margin by interference screw fixation. All patients had a minimum of 50 weeks' follow-up. Preoperative and postoperative patient data including visual analog scale scores (obtained by all surgeons), objective shoulder scores (Simple Shoulder Test and University of California, Los Angeles scores obtained by 2 and 4 surgeons, respectively), and need for revision surgery (obtained by all surgeons) were retrospectively analyzed, the results are reported, and statistical analysis was performed. RESULTS: After the application of our exclusion criteria, 1,083 patients were included in the analysis. The mean follow-up period was 136 weeks. The overall revision surgery rate for this group was 4.1% (44 of 1,083). Revision for biceps tenodesis-related issues was needed in only 4 cases (for a biceps tenodesis-related revision rate of 0.4%). Pain scores improved from 6.47 preoperatively to 1.08 postoperatively (P < .0001). University of California, Los Angeles scores improved from 14.9 preoperatively to 30.1 postoperatively (P < .0001), and Simple Shoulder Test scores improved from 2.7 preoperatively to 10.2 postoperatively (P < .0001). CONCLUSIONS: Arthroscopic biceps tenodesis performed at the articular margin results in a low surgical revision rate, a low rate of residual pain, and significant improvement in objective shoulder outcome scores. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

70° frontal visualization of lateral compartment of the elbow allows extensor carpi radialis brevis tendon release with preservation of the radial lateral collateral ligament.

PURPOSE: To determine whether the radial component of the lateral collateral ligament (R-LCL) and extensor carpi radialis brevis (ECRB) are consistently visible, using a 70° arthroscope, as parallel structures in the extra-articular space of the elbow, and to evaluate the clinical outcomes of these techniques in a series of patients. METHODS: An arthroscopic ECRB tendon release was performed between 2008 and 2010. Eighteen patients were retrospectively evaluated at a minimum of 24 months' follow-up. The surgeon performed the ECRB release while protecting the R-LCL and viewing the structures extra-articularly with a 70° arthroscope through the anteromedial portal. Patients underwent surgery if they presented with localized tenderness and pain not responding to conservative treatment for 12 months and had magnetic resonance imaging scans indicating tendinopathy or degeneration. Arthritis, posterolateral rotatory instability, trauma, and previous surgeries were exclusion criteria. Intraoperative videos were reviewed and a clinical examination was performed by an independent reviewer at 24 months postoperatively. Patients were also evaluated with the Mayo Elbow Performance Score; Andrews-Carson score; and shortened Disabilities of the Arm, Shoulder and Hand questionnaire. Direct varus stress was applied in extension and flexion (40°), and the posterolateral pivot-shift and chair tests were performed. RESULTS: Visualization with the 70° arthroscope through the anteromedial portal was successful in all of the cases (100%). Visualization of the residual ECRB tendon stump, as well as the posterior common extensor tendon, was also achieved 94% of the time. The final mean Mayo Elbow Performance Score and Andrews-Carson score were 82.5 (range, 60 to 100) and 185.3 (range, 125 to 200), respectively. The mean postoperative score on the shortened Disabilities of the Arm, Shoulder and Hand questionnaire was 20.14 (range, 5 to 57.5). Clinical tests showed stability in all the cases. CONCLUSIONS: The 70° arthroscope allows visualization of the ECRB insertion and R-LCL frontally and in parallel. A surgical plane could be created between the structures. The clinical outcome was good or excellent in 78% of the cases. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Associated lesions requiring additional surgical treatment in grade 3 acromioclavicular joint dislocations.

PURPOSE: To evaluate the incidence of associated pathologic shoulder lesions that were addressed surgically in grade 3 acromioclavicular joint (ACJ) dislocations, as well as to compare this incidence between younger and older patients and between acute and chronic cases. METHODS: In this multicenter nonrandomized retrospective study, 98 patients operated on for grade 3 ACJ dislocation underwent concomitant arthroscopic evaluation for the identification and treatment of any associated lesions. The type and treatment of associated lesions were collected in a central database and analyzed. We classified patients according to age (<45 years and ≥ 45 years) and according to the length of time between trauma and surgical treatment (≤ 30 days and ≥ 120 days), obtaining the following stratification: younger acute, older acute, younger chronic, and older chronic. RESULTS: Of the patients, 42 (42.8%) were diagnosed with at least 1 additional pathologic lesion, and 29 (29.5%) required a dedicated additional treatment. Rates of treatment on associated lesions were analyzed: younger versus older groups presented a significant difference, as did younger acute versus older acute groups; SLAP and posterior rotator cuff tear treatments represented 24 of the 35 additional surgeries (68.5%). CONCLUSIONS: The overall rate of associated pathologic lesions requiring additional surgical treatment in patients with ACJ dislocation was 29.5%. Patients aged 45 years or older had a greater risk of presenting with associated lesions that needed to be surgically addressed (odds ratio, 3.01). The overall rates of associated surgical lesions in acute versus chronic cases were not shown to be significantly different. LEVEL OF EVIDENCE: Level IV, prognostic case series.