Clavicular tunnel widening after acromioclavicular joint reconstruction: comparison between single and double clavicular tunnel techniques.

Acromioclavicular joint (ACJ) reconstruction using artificial ligaments is a common surgical treatment for Rockwood grade III or higher injuries. These techniques use bone tunnels in the clavicle and coracoid to insert the Tightrope implants. This multicenter retrospective study compares long term radiographic follow up of clavicular tunnel widening in two groups of patients with high-grade ACJ injury who underwent reconstruction using two different surgical techniques. The first group of 23 patients underwent an arthroscopic single clavicular tunnel ACJ reconstruction. The second group of 23 patiënts underwent an open double clavicular tunnel reconstruction. Inclusion criteria are Rockwood grade III or higher injury and minimum 18 months of follow-up. Exclusion criteria are distal clavicle fracture and additional stabilization techniques. Radiographic results were measured on anteroposterior shoulder radiographs taken at the first and last follow-up. Clavicular tunnel widening is the main outcome measurement. Secondary outcomes are heterotopic ligament calcifications, migration of buttons, tunnel fracture and loss of acromioclavicular reduction. The mean clavicular tunnel widening in the single clavicular tunnel technique is 1.91 mm. In the double clavicular tunnel technique, the widening of the medial tunnel is 2.52 mm and 3.59 mm in the lateral tunnel. The difference in widening between the single tunnel and the lateral tunnel is significant (p=0.003). A very clear observation on all follow-up X-rays was a reorientation of the clavicular tunnels towards the coracoid. The double clavicular tunnel technique has more tunnel widening in both tunnels compared to the single bundle technique.

Surgical treatment of acromioclavicular joint dislocation of Rockwood III/IV: a retrospective study on clavicular hook plate versus arthroscopic TightRope loop titanium button.

PURPOSE: To compare the clinical efficacy of arthroscopic TightRope loop titanium button and clavicular hook plate in the treatment of acromioclavicular joint (ACJ) dislocation of Rockwood III/IV. METHODS: A retrospective analysis of patients with ACJ dislocation in our hospital from January 2018 to December 2020 was conducted. The patients were assigned to be treated with arthroscopic TightRope loop titanium button (TR group) or clavicular hook plate (HP group). The preoperative, intraoperative and postoperative data and imaging findings of the two groups were compared. RESULTS: A total of 58 eligible patients were enrolled in this study. Compared with HP group, TR group had shorter incision length and less blood loss during operation. Postoperative follow-up ranged from 12 to 24 months (mean 15.4 months). At 6 months and 12months postoperatively, compared with HP group, TR group had lower VAS and higher CMS, and the difference was statistically significant. At 12 months postoperatively, compared with HP group, TR group had lower ACJ gap and coracoclavicular joint(CCJ) distance, and the difference was statistically significant.In HP group, there were 3 cases of subacromial impact, 1 case of redislocation, 2 cases of traumatic arthritis and 2 cases of wound infection. There was 1 case of redislocation in TR group. CONCLUSIONS: Compared with clavicular hook plate, arthroscopic TightRope loop titanium button is minimally invasive, safe and effective in the treatment of ACJ dislocation, and has a good trend in clinical application.

In Vivo Analysis of Acromioclavicular Kinematics and Distance During Multiplanar Humeral Elevation.

BACKGROUND: Knowledge of acromioclavicular (AC) joint kinematics and distance may provide insight into the biomechanical function and development of new treatment methods. However, accurate data on in vivo AC kinematics and distance between the clavicle and acromion remain unknown. PURPOSE/HYPOTHESIS: The purpose of this study was to investigate 3-dimensional AC kinematics and distance during arm elevation in abduction, scaption, and forward flexion in a healthy population. It was hypothesized that AC kinematics and distance would vary with the elevation angle and plane of the arm. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 19 shoulders of healthy participants were enrolled. AC kinematics and distance were investigated with a combined dual fluoroscopic imaging system and computed tomography. Rotation and translation of the AC joint were calculated. The AC distance was measured as the minimum distance between the medial border of the acromion and the articular surface of the distal clavicle (ASDC). The minimum distance point (MDP) ratio was defined as the length between the MDP and the posterior edge of the ASDC divided by the anterior-posterior length of the ASDC. AC kinematics and distance between different elevation planes and angles were compared. RESULTS: Progressive internal rotation, upward rotation, and posterior tilt of the AC joint were observed in all elevation planes. The scapula rotated more upward relative to the clavicle in abduction than in scaption (P = .002) and flexion (P = .005). The arm elevation angle significantly affected translation of the AC joint. The acromion translated more laterally and more posteriorly in scaption than in abduction (P < .001). The AC distance decreased from the initial position to 75° in all planes and was significantly greater in flexion (P < .001). The MDP ratio significantly increased with the elevation angle (P < .001). CONCLUSION: Progressive rotation and significant translation of the AC joint were observed in different elevation planes. The AC distance decreased with the elevation angle from the initial position to 75°. The minimum distance between the ASDC and the medial border of the acromion moved anteriorly as the shoulder elevation angle increased. CLINICAL RELEVANCE: These results could serve as benchmark data for future studies aiming to improve the surgical treatment of AC joint abnormalities to restore optimal function.

Mid-term clinical and sonographic outcomes of minimally invasive acromioclavicular joint reconstruction: mini-open versus arthroscopically assisted.

INTRODUCTION: The current literature describes various operative stabilization strategies which achieve good clinical outcomes after acute acromioclavicular joint (ACJ) dislocation. The aim of this study was to compare the mid-term clinical and sonographic treatment outcomes after minimally invasive mini-open and arthroscopic reconstruction. MATERIALS AND METHODS: We conducted a retrospective two-center study of patients with acute ACJ dislocation. Surgical treatment was performed using either a mini-open approach (MIOP) or an arthroscopic technique (AR). The primary outcome parameters of this study were the sonographically measured acromioclavicular (ACD) and coracoclavicular distances (CCD). Secondary outcome parameters included the Constant-Murley score (CS), range of motion (ROM), postoperative pain scale (VAS), return to daily routine, return to sports, complications, as well as operative revisions. RESULTS: After a mean follow-up of 29 months, 30 patients were included in this study with an average age of 41.3 ± 14.8 years (MIOP) and 41.2 ± 15.4 years (AR). The sonographic ACD (MIOP 9.11 mm vs. AR 8.93 mm, p = 0.41) and CCD (MIOP 25.08 mm vs. AR 24.36 mm, p = 0.29) distances showed no statistically significant differences. Furthermore, there was no statistically significant difference when compared to the contralateral side (p = 0.42). With both techniques, patients achieved excellent clinical outcome parameters without statistically significant differences in CS (MIOP 95 vs. AR 97, p = 0.11) and VAS (MIOP 1.76 vs. AR 1.14, p = 0.18). The return to daily activity and return to sport rates did not differ. There were neither complications nor revisions in both groups. CONCLUSION: Both minimally invasive techniques for acute ACJ stabilization achieved excellent clinical and sonographic outcomes without one technique being statistically superior to the other.

Management of acute grade IV and greater acromioclavicular dislocations: Open acromioclavicular brace versus arthroscopic double DogBone® endobutton.

INTRODUCTION: Several surgical techniques exist to manage grade IV acute acromioclavicular dislocation (ACD). However, the conventional acromioclavicular brace technique (ACB) has never been compared to the arthroscopic DogBone® (DB) double endobutton technique. The aim of this work was to compare the functional and radiological results of DB stabilization with those of ACB. HYPOTHESIS: DB stabilization provides similar functional results with a low rate of radiological recurrences compared to ACB. MATERIAL AND METHODS: This is a case-control study comparing 17 cases of ACD operated by DB (DB group) between January 2016 and January 2021 with 31 cases of ACD operated by ACB (ACB group) between January 2008 and January 2016. The primary outcome was the difference in the D/A ratio (reflecting vertical displacement) measured on an anteroposterior acromioclavicular (AC) X-ray compared between the 2 groups at one-year after surgery. The secondary outcome was a clinical evaluation at one-year using the Constant score and clinical AC instability. RESULTS: At revision, the mean D/A ratio in the DB and ACB groups was 0.4±0.5 [-0.4-1.6] and 1.6±0.3 [0.8-3.1] respectively (p>0.05). Two patients (11.7%) in the DB group had implant migration with radiological recurrence while 14 patients (33%) had radiological recurrence in the ACB group (p<0.05). CONCLUSION: The DB technique limits the radiographic recurrence of acute ACD with an equivalent functional result at 1-year postoperatively compared to the conventional ACB technique, which implicitly requires a second operation for hardware removal. The DB technique has become the technique of choice in first-line treatment of acute grade IV ACD. LEVEL OF EVIDENCE: III; retrospective case-control series.

3D C-arm navigated acromioclavicular joint stabilization.

INTRODUCTION: Surgical treatment options for acromioclavicular joint separations are varied. Frequently, suspension devices (SD) are inserted for stabilization under arthroscopic view. This study investigates the feasibility and accuracy of three-dimensional (3D) digital-volume-tomography (DVT) C-arm navigated implantation with regard to the general trend toward increasingly minimally invasive procedures. MATERIALS AND METHODS: The implantation of a TightRope® suture button system (SD) via a navigated vertical drill channel through the clavicle and coracoid was investigated in 10 synthetic shoulder models with a mobile isocentric C-arm image intensifier setup in the usual parasagittal position. Thereby, in addition the placement of an additive horizontal suture cerclage via a navigated drill channel through the acromion was assessed. RESULTS: All vertical drill channels in the Coracoclavicular (CC) direction could be placed in a line centrally through the clavicle and the coracoid base. The horizontal drill channels in the Acromioclavicular (AC) direction ran strictly in the acromion, without affecting the AC joint or lateral clavicle. All SD could be well inserted and anchored. After tensioning and knotting of the system, the application of the horizontal AC cerclage was easily possible. The image quality was good and all relevant structures could be assessed well. CONCLUSION: Intraoperative 3D DVT imaging of the shoulder joint using a mobile isocentric C-arm in the usual parasagittal position to the patient is possible. Likewise, DVT navigated SD implantation at the AC joint in CC and AC direction on a synthetic shoulder model. By combining both methods, the application in vivo could be possible. Further clinical studies on feasibility and comparison with established methods should be performed.

The V angle compliments radiographic assessment of acute acromioclavicular joint dislocations by differentiating between Rockwood types III versus V and by considering dynamic horizontal translation in coronal radiographs.

PURPOSE: Acromioclavicular joint (ACJ) dislocations are usually graded radiographically according to Rockwood, but differentiation between Rockwood types III and V may be ambiguous. The potentially clinically relevant horizontal instability is barely addressed in coronal radiographs. It was hypothesized that a new radiologic parameter (V angle) would complement ACJ diagnostics on anteroposterior radiographs by differentiating between cases of Rockwood III and V while also considering the aspect of dynamic horizontal translation (DHT). METHODS: Ninety-five patients with acute ACJ dislocations (Rockwood types III and V) were included retrospectively between 2017 and 2020. On anteroposterior views (weightbearing: n = 62, non-weight-bearing: n = 33), the coracoclavicular (CC) distance and the newly introduced V angle for assessing scapular orientation were measured bilaterally. This angle is referenced between the spinal column and a line crossing the superior scapular angle and the crossing point between the supraspinatus fossa and the medial base of the coracoid process, reported as the side-comparative difference (non-injured side *minus* injured side). DHT on Alexander views was divided into stable, partially unstable or completely unstable. RESULTS: The V angle on the injured side alone (mean 50.0°; 95% confidence interval (CI), 48.6°-51.3°) showed no correlation with the side-comparative CC distance [%] (r = - 0.040; n.s.). Thus, the V angle on the non-injured side was considered, displaying a normal distribution (n.s.) with a mean of 58.0° (95% CI, 56.6°-59.4°). The side-comparative V angle showed a correlation with the side-comparative CC distance (r = 0.83; p < 0.001) and was able to differentiate between Rockwood types III (4.7°; 95% CI, 3.9°-5.5°; n = 39) and V (10.3°; 95% CI, 9.7°-11.0°; n = 56) (p < 0.001). A cut-off value of 7° had a 94.6% sensitivity and an 82.1% specificity (area under curve, AUC: 0.954; 95% CI, 0.915-0.994). The side-comparative V angle was greater for cases with complete DHT (8.7°; 95% CI, 7.9°-9.5°; n = 78) than for cases with partial DHT (4.8°; 95% CI, 3.3°-6.3°; n = 16) (p < 0.001). A cut-off value of 5° showed a sensitivity of 84.6% and a specificity of 66.7% (AUC 0.824; 95% CI, 0.725-0.924). CONCLUSION: The scapular-based V angle on anteroposterior radiographs distinguishes between Rockwood types III and V as well as cases with partial or complete DHT. STUDY DESIGN: Diagnostic study. LEVEL OF EVIDENCE: Level II.

Management of Acromioclavicular Joint Injuries: A Historic Account.

There has been a rapid evolution in best practice management of acromioclavicular (AC) joint injuries. AP, Zanca, scapular Y, and dynamic axillary radiographic views provide optimal visualization of the joint and may assess for the presence of horizontal AC instability. Severity of AC joint pathology is classified according to the 6-tier Rockwood scoring system. Over 160 surgical techniques have been described for AC joint repair and reconstruction in the last decade; as a result, determining the optimal treatment algorithm has become increasingly challenging secondary to the lack of consistently excellent clinical outcomes.

A novel method for estimating sternoclavicular posterior rotation with promising accuracy: A validity comparison with minimizing acromioclavicular rotation approach.

The human shoulder complex's motion is modeled by nine rotational degrees of freedom (DoF) at the sternoclavicular (SC), acromioclavicular (AC), and glenohumeral joints. Non-invasive measurement of these rotations is desirable for shoulder kinematic assessment or musculoskeletal modeling. Accuracy of the conventional method for estimating SC posterior rotation is unclear and might be overestimated because it assumes no rotation in the AC joint. We aimed to explore whether our new method, allowing AC rotation, provides a more accurate estimation of SC posterior rotation than the conventional method. We compared estimates by both methods, in 18 postures among 8 healthy men, with those measured by the registration method from magnetic resonance images. Posthoc analyses showed significant differences between the registration and conventional methods in all 18 postures and in only one posture when compared to our method. While the conventional method tended toward overestimation and showed a 22.7° root-mean-square error for all postures, the new method had greater accuracy (6.8° root-mean-square error). By combining this method with the scapulothoracic rotation measurement method and other traditional methods, it should be possible to indirectly measure 3-DoF AC rotation, implying that non-invasive measurement of all 9-DoF rotations of the shoulder complex would now be possible.

Dynamic Horizontal Instability of the Acromioclavicular Joint: A Case Report.

CASE: A 19-year-old female patient with a history of shoulder trauma 6 years ago presented with dynamic horizontal instability of the acromioclavicular joint (ACJ). She was treated with open ACJ reconstruction using gracilis allograft and showed a satisfactory clinical result at 1-year follow-up. CONCLUSION: Dynamic pure horizontal instability of the ACJ is a rare entity with only 6 cases reported in the literature. Till now, all reported patients who necessitated surgical treatment failed because of residual instability and/or pain. We present the seventh case of this type with a successful clinical outcome.

Dynamic evaluation of the sternoclavicular and acromioclavicular joints using an upright four-dimensional computed tomography.

In the analysis of the shoulder complex, the sequential changes occurring in the sternoclavicular and acromioclavicular joints during active shoulder motion are challenging to track. This study aimed to investigate the in vivo sternoclavicular and acromioclavicular joint motions during active elevation, including the sequential changes in these joint spaces using upright four-dimensional computed tomography (4DCT). Bilateral shoulders of 12 healthy volunteers upright 4DCT were obtained during active elevation similar to a "hands up" motion. The sternoclavicular and acromioclavicular rotation angles, joint distances, and closest points on the clavicle relative to the thorax and scapula were evaluated during 10°-140° of humerothoracic elevation. During humerothoracic elevation, the clavicle elevated, retracted, and rotated posteriorly relative to the thorax, whereas the scapula rotated upwardly, internally, and posteriorly relative to the clavicle. All the sternoclavicular and acromioclavicular joint rotation angles were significantly different at ≥ 30°-50° of humerothoracic elevation compared with 10° of humerothoracic elevation. The mean sternoclavicular and acromioclavicular joint distances were 2.2 ± 1.1 mm and 1.6 ± 0.9 mm, respectively. The closest points were located on the anteroinferior part of the medial and lateral clavicle in the sternoclavicular and acromioclavicular joints, respectively. Significant differences were observed in the acromioclavicular joint distance and anterior/posterior movements of the closest points in the sternoclavicular and acromioclavicular joints compared with 10° of humerothoracic elevation. Our sternoclavicular and acromioclavicular closest point results indicate that the impingement tends to occur at the anteroinferior part of the medial and lateral aspects of the clavicle and may be related to osteoarthritis.

Optimizing Treatment for Combined Midshaft Clavicle Fracture and Acromioclavicular Joint Injury: A Case Study Highlighting the Efficacy of Knowles Pin Fixation.

BACKGROUND An ipsilateral fracture of the midshaft clavicle with dislocation of the acromioclavicular joint (ACJ) is a rare combination injury and almost always occurs following high-energy trauma. Currently, there is no optimal surgical approach for this kind of rare injury. We present a 60-year-old man with a traumatic combined linear midshaft clavicle fracture and ACJ injury simultaneously treated with Knowles pin fixation. CASE REPORT A 60-year-old male patient presented a linear midshaft clavicle fracture in the emergency room (ER) due to a road traffic accident. A linear fracture progressed to a displaced fracture at followup in the outpatient orthopedic department 3 days later. After open reduction with Knowles pin fixation for displaced clavicle fracture, postoperative followup radiographs revealed unexpected ipsilateral type V ACJ dislocation according to Rockwood classification. The next day, a closed reduction with percutaneous Knowles pin fixation was performed for ACJ dislocation. At the 1-year followup, radiographic and clinical results demonstrated complete union of the clavicle fracture and anatomic reduction of the ACJ with painless and full range of motion. CONCLUSIONS This report highlights that even a linear midshaft clavicle fracture can be combined with ipsilateral ACJ dislocation if the traumatic injury was caused by a high-energy road traffic accident. Therefore, an intraoperative stress view of the injured shoulder is recommended to recheck the stability of the ACJ after the clavicle fracture fixation to prevent a missed ACJ injury. In our case, an excellent outcome was achieved by using Knowles pin fixation simultaneously to treat the dual shoulder injury.

Long-term follow-up in a single-bundle arthroscopic acromioclavicular joint reconstruction after Rockwood III to VI dislocation.

This retrospective study presents the clinical and radiographic results of a single-bundle arthroscopic acromioclavicular joint reconstruction in 45 patients with a mean follow-up of 4.8 years. Patients with a Rockwood grade III or higher were included. Clinical results were based on satisfaction, pain and functional scores. These outcome scores were compared to coracoclavicular distance measurement on X-ray. Secondly, clinical outcome scores were compared between patients who had surgery in the first 6 weeks after trauma and patients treated after 6 weeks. Overall, X-ray showed a good reduction in 71.1% of the patients (less than 50% loss of reduction). These patients showed better clinical results than patients with radiographical failure in terms of satisfaction (p = .001), Constant (p = .001), DASH (p = .031) and SPADI (p = .005) scores. In total, 78% of the patient had surgery in the first 6 weeks after trauma. When treated later (mean time to surgery of 8.8 months), patients showed worse results for satisfaction (p = .003) and DASH score (p = .006), suggesting that treatment of chronic cases might warrant additional fixation techniques. As a conclusion, these results showed that, in the acute approach, single-bundle arthroscopic coracoclavicular fixation is a good treatment in acromioclavicular joint dislocation Rockwood grade III or higher.

Treatment of coracoid process fractures combined with acromioclavicular joint dislocation using clavicular hook plate.

BACKGROUND: The injury mechanism of acromioclavicular (AC) dislocation combined with coracoid process (CP) fracture is not clear, and there is no consensus on its treatment. This study was performed to evaluate the diagnosis of CP fractures combined with AC dislocation and the effectiveness of operative treatment using a clavicular hook plate. METHODS: Eighteen patients with CP fractures combined with AC dislocation were treated with a clavicular hook plate from May 2012 to June 2021. The patients comprised 10 male and 8 female patients with an average age of 38 years (range, 16-54 years). The injury was caused by falling in 15 patients, traffic accidents in 2 patients, and falling from a height in 1 patient. The Eyres type of CP fracture was type II in 1 patient, type III in 11 patients, type IV in 3 patients, and type V in 3 patients. The Ogawa type of CP fracture was type I in 17 patients and type II in 1 patient. The Rockwood type of AC dislocation was type V in 1 patient, variation type III in 15 patients, and variation type V in 2 patients. The interval from injury to the operation was 3 days (range, 1-7 days). Postoperative complications and CP fracture healing were recorded. Functional assessment at the last follow-up was performed by an independent reviewer using the Constant score and visual analog scale score. RESULTS: All 18 patients were followed up for a mean period of 49 months (range, 12-123 months). Nine patients had acromion osteolysis and 3 patients had CP fracture nonunion (Eyres type II, III, and V in 1 patient each); however, no patients developed shoulder pain, incision infection, limitation of shoulder movement, clinical symptoms of subcoracoid impingement, or AC dislocation relapse. At the last follow-up, the mean Constant score was 99 (range, 94-100). CONCLUSIONS: The possibility of CP fracture should be considered in patients with AC dislocation to avoid a missed diagnosis. Fixation with a clavicular hook plate is a feasible treatment for CP fracture combined with AC dislocation and provides a satisfactory outcome. CP fracture healing may be related to the fracture morphology.

Clavicular Tunnel Widening After Acromioclavicular Stabilization Shows Implant-Dependent Correlation With Postoperative Loss of Reduction.

PURPOSE: To radiographically describe, quantify, and compare clavicular tunnel widening (cTW) of 2 different types of stabilization devices and investigate a possible correlation between cTW and loss of reduction. METHODS: In a retrospective analysis of single-center registry data, we compared patients who were treated for an acute AC dislocation (Rockwood types III to V) with either the AC Dog Bone (DB) or low-profile AC (LP) repair systems. On 6-week and 6-month postoperative radiographs, we measured clavicle height and tunnel diameter. We calculated the button/clavicle filling (B/C) ratio to quantify how much of the clavicular tunnel height is covered by the low-profile inlet. The association between B/C ratio and the extent of cTW was defined, and we also compared cTW between treatment groups. Reduction of the AC joint was graded as either stable, partially dislocated or dislocated depending on the AC ratio. A 2-sample t-test was used for comparing cTW progression between the 2 groups. For continuous variables between more than 2 groups, the Kruskal-Wallis test was used. RESULTS: Of 65 eligible patients, there were 37 and 28 included in the DB and LP groups, respectively. Overall, cTW was conically shaped with transclavicular widening noted in the DB group and cTW developing strictly inferior to the button in the LP group. For both implants, mean maximal cTW was 7.1 mm and located at the inferior cortex; the B/C ratio was not associated with increased inferior cTW (r = -0.23, P = .248). Only LP patients with complete loss of reduction had significantly increased cTW (P = .049). CONCLUSIONS: Conical-shaped cTW is a common implant-independent phenomenon after AC stabilization using suture-button devices. It occurs only at the suture-bone interface and is less excessive for the LP implant. There is an association between increased cTW and loss of reduction specific to the LP implant only. LEVEL OF EVIDENCE: Level III, therapeutic study.

Management of Acute High-Grade Acromioclavicular Joint Dislocations: Comparable Clinical and Radiological Outcomes After Bidirectional Arthroscopic-Assisted Stabilization With the Single Low-Profile Suture Button Technique Versus Double-Suture Button Technique.

PURPOSE: To compare the 2-year clinical and radiological outcomes of an arthroscopic-assisted bidirectional stabilization procedure using a single low-profile (LPSB) or double-suture button (DSB) technique with additional percutaneous acromioclavicular (AC) cerclage fixation for patients with acute high-grade AC joint dislocation. METHODS: This retrospective cohort study compared male patients aged between 18 and 56 years with acute high-grade AC joint dislocation fixed with either a LPSB or DSB technique. Patients were examined at least 24 months after surgery. Subjective Shoulder Value (SSV), Taft (TF), and Acromioclavicular Joint Instability (ACJI) scores were evaluated. Coracoclavicular difference, ossification, AC joint osteoarthritis, and dynamic posterior translation (DPT) were assessed on bilateral anteroposterior stress radiographs and modified Alexander views. The revision rate due to implant conflict and duration of surgery were reported. Group outcome differences were analyzed using standardized hypothesis tests. RESULTS: 28 patients aged 39.2 (LPSB) and 36.4 years (DSB) (P = .319; CI: -2.77-8.34) were eligible per cohort. The follow-up was 30.5 (LPSB) and 37.4 months (DSB) (P = .02; CI: -12.73-1.08). LPSB patients rated a significantly higher SSV (93.2% vs 81.9% [DSB]; P = .004). TF and ACJI scores were similar between the groups. Coracoclavicular difference markedly decreased from 12 mm to 3 mm for both cohorts (P < .001). Ossification was identified in over 85% in both cohorts (P = .160; CI -0.77-0.13) and osteoarthritis in 21.4% (LPSB) and 39.3% (DSB) (P = .150). Persistent DPT was found in around 30% for both cohorts (P = .561; CI -0.26-0.48). The revision rates were 0% (LPSB) and 7% (DSB) (P = .491). LPSB surgery was shorter (59.7 vs 71.5 mins [DSB]) (P = .011). CONCLUSIONS: The results of the LPSB and DSB techniques with additional percutaneous AC cerclage fixation showed comparable outcomes with excellent clinical and satisfactory radiological results. The assessment of the subjective patient satisfaction was in favor of the LPSB technique and no postoperative revision event was observed following this procedure. LEVEL OF EVIDENCE: Level III, retrospective comparative therapeutic trial.

Complications after operative treatment of high-grade acromioclavicular injuries.

BACKGROUND: Treatment of Rockwood type III-V acromioclavicular (AC) joint injuries remains controversial. Numerous reconstruction techniques have been proposed. The purpose of this study was to describe the complication profile in a large cohort of patients who underwent surgical management of AC joint separations using a variety of reconstruction strategies. METHODS: All patients who underwent surgery for AC joint injuries from 2013 to 2019 at a single institution were identified. Chart review was performed to capture patient demographics, radiographic measurements, operative techniques, postoperative complications, and revision surgery. Structural failure was defined as a radiographic loss of reduction of greater than 50% when comparing immediate and final postoperative imaging. Logistic regression analysis was performed to identify risk factors for complications and revision surgery. RESULTS: Of the 279 patients included in the study, 66 (24%) had type III separations, 20 (7%) type IV, and 193 (69%) type V. Fifty-three percent underwent surgery acutely (<6 weeks of injury), and 40% were chronic (>3 months). A total of 252 of the 279 surgeries (90%) were performed open and 27 (10%) were arthroscopically assisted. Allograft was used in 164 of 279 (59%) cases. Specific operative techniques (with or without allograft) included hook plating (1%), modified Weaver Dunn (16%), cortical button fixation (18%), and suture fixation (65%). At mean 28-week follow-up, 108 complications were identified in 97 patients (35%). Complications were identified at mean 20 ± 21 weeks. Sixty-nine structural failures (25%) were identified. Persistent AC joint pain requiring injection, clavicle fracture, adhesive capsulitis, and hardware complications were the other most common complications. Twenty-one patients (8%) underwent unplanned revision surgery at mean 38 ± 28 weeks after the index procedure, with the most common indication for structural failure, hardware complications, or fracture of the clavicle or coracoid. Patients who had surgery after 6 weeks from injury had a significantly greater risk of having a complication (odds ratio [OR] 3.19, 95% confidence interval [CI] 1.34-7.77, P = .009) and a significantly greater risk of having structural failure (OR 2.65, 95% CI 1.38-5.28, P = .004). Patients who had an arthroscopic technique had a greater risk of structural failure (P = .002). Complications, structural failure, and revision surgery were not significantly correlated with use of allograft or specific operative techniques. CONCLUSION: Surgical management of AC joint injuries is associated with a relatively high complication profile. Loss of reduction in the postoperative period is common. However, the revision surgery rate is low. These findings are important for patient preoperative counseling.

[Minimally Invasive Techniques for the Treatment of Acute and Chronic Acromioclavicular Joint Instabilities]. / Minimalinvasive Techniken zur Therapie der Schultereckgelenksprengung.

Acromioclavicular joint instabilities are one of the most common injuries of the shoulder girdle. Diagnostic measures include the vertical and horizontal components of instability. The main goals of treatment include pain reduction, joint stabilization, and return to physical activity. For operative treatment, there are numerous techniques available. Recently, minimally-invasive techniques were developed and showed equal results as with open approach. These procedures facilitate simultaneous treatment of concomitant shoulder lesions and reduce soft tissue trauma as well as the risk of infection. This article presents an overview of such minimally-invasive techniques for both acute and chronic instabilities. Both techniques address the aspect of horizontal instability, which was found to compromise clinical results. For an acute injury, we describe the use of a low-profile button system combined with an additional acromioclavicular cerclage. In the chronic setting with a bidirectional (vertical and horizontal) instability, a free tendon graft combined with a single TightRope augmentation is recommended.

Acromioclavicular Joint Injuries in Sport.

ABSTRACT: Sport-related shoulder injuries, including disruptions to the acromioclavicular joint (ACJ), are common. An ACJ injury is classified by the degree and direction of the clavicle displacement. Although the diagnosis can be made clinically, standard radiographic views are important to determine the severity of the ACJ disruption and assess for concurrent injuries. The majority of ACJ injuries can be managed nonoperatively; however, surgical treatment is indicated in some cases. Long-term outcomes are generally favorable for most ACJ injuries, and athletes generally return to sport without functional limitations. This article provides an in-depth discussion regarding all aspects of ACJ injuries, including clinically relevant anatomy, biomechanics, evaluation, treatment, and complications.