Clavicular tunnel widening in chronic acromioclavicular joint instabilities after primary versus revision arthroscopically-assisted acromio- and coracoclavicular stabilization.

Purpose: To evaluate joint reduction (loss of reduction [LOR]; dynamic posterior translation [DPT]) and clavicular tunnel widening (cTW) in patients treated with arthroscopically-assisted acromioclavicular joint (ACJ) stabilization after previously failed nonoperative versus surgical treatment. Methods: Patients undergoing arthroscopically-assisted ACJ stabilization (bidirectional tendon allograft with a low-profile TightRope) after previously failed nonoperative versus surgical treatment were included retrospectively. Bilateral anteroposterior stress views served for evaluating LOR (side-comparative coracoclavicular distance [CCD]) and cTW at a 6-weeks- and 6-months-follow-up (FU) and for evaluating the filling ratio (FR, vertical device insertion depth relative to clavicle height) at the 6-weeks-FU. Postoperative DPT was assessed on Alexander's views. Results: Twenty-seven patients (20 male, mean age 46.1 ± 14.8 years) were included (prior treatment: nonoperative: n = 15; surgical: n = 12). There were no differences in LOR, DPT or cTW between groups postoperatively. Initial CCD-symmetry at the 6-weeks-FU (CCD: -0.1 mm [95% confidence interval, CI, -2 to 1.4 mm]) was followed by LOR at the 6-months-FU (CCD: -3.5 mm [95% CI, -5.2 to -1.9 mm]; p < 0.001). cTW increased towards the inferior cortex, compared to the superior cortex and the intermediate level (p < 0.001, respectively). cTW at the inferior cortex was associated with more LOR (r = -0.449; p = 0.024) and DPT (r = 0.421; p = 0.036), dependent on a smaller FR (r = -0.430; p = 0.032). Conclusion: Patients undergoing arthroscopically-assisted ACJ stabilization for chronic bidirectional ACJ instabilities showed comparable radiologic results after previous nonoperative versus surgical treatment. cTW increased towards the inferior cortex and was associated with recurrent vertical and horizontal instability, related to a smaller FR. More research into reduced cTW, for example, by a more filling device, should be performed. Level of Evidence: Level III, retrospective comparative study.

Concomitant Glenohumeral Pathologies in Patients with Acromioclavicular Joint Dislocations: How Do Acute and Chronic Instabilities Differ?

Background: Concomitant glenohumeral pathologies may be present in patients with acromioclavicular joint (ACJ) dislocations. This study aims to record and compare the prevalence and treatment of CGP in cases with acute and chronic ACJ dislocations. Methods: This retrospective cross-sectional binational, bicentric study included patients that underwent arthroscopically assisted stabilization for acute (group A) and chronic (group C) ACJ dislocations. Intraoperatively, CGPs and eventual treatments (debridement and reconstructive measures) were recorded. Results: The study included 540 patients (87% men; mean age 39.4 years), with 410 (75.9%) patients in group A and 130 (24.1%) in group C. Patients in group C were older (p < 0.001). The CGP prevalence was 30.7%, without a difference between groups A and C (p = 0.19). Supraspinatus tendon (SSP) and labral lesions were most common. Within group C, CGPs were more prevalent in surgery-naïve patients (p = 0.002). Among 49 patients with previous surgical treatment, CGPs tended to be more common in patients with prior open surgery than arthroscopically assisted surgery (p = 0.392). Increased CGP prevalence was associated with higher age (r = 0.97; p = 0.004) (up to 63% in the oldest age group, but also 17% for youngest age group) and higher in cases with Rockwood type-IIIB injuries compared to type-V injuries (p = 0.028), but type-IIIB injuries included more group C cases (p < 0.001). The most frequently found CGPs were treated by debridement rather than reconstructive interventions (SSP and labrum: p < 0.001, respectively). Conclusions: This study shows that one in three patients with ACJ instabilities has a CGP, especially elderly patients. Most of the CGPs were treated by debridement rather than constructive interventions.

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.

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.

[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.

In vivo analysis of the circles measurement supports its use in evaluating acromioclavicular joint dislocations.

BACKGROUND: Classification and treatment of acromioclavicular joint (ACJ) dislocations according to the Rockwood classification is controversial. The "circles measurement" on Alexander views was proposed to enable a clear assessment of displacement in ACJ dislocations. However, the method and its ABC classification were introduced on a Sawbones model based on exemplary Rockwood scenarios without soft tissue. This is the first in vivo study to investigate the circles measurement. We aimed to compare this new measurement method with the Rockwood classification and the previously described semiquantitative degree of dynamic horizontal translation (DHT). METHODS: A total of 100 consecutive patients (87 men and 13 women) with acute ACJ dislocations between 2017 and 2020 were included retrospectively. The mean age was 41 years (range, 18-71 years). ACJ dislocations on panoramic stress views were classified according to Rockwood type (type II, n = 8; type IIIA, n = 9; type IIIB, n = 24; type IV, n = 7; and type V, n = 52). On Alexander views, where the hand of the affected arm rested on the contralateral shoulder, the circles measurement and the semiquantitative degree of DHT (none, n = 6; partial, n = 15; or complete, n = 79) were assessed. Convergent and discriminant validity of the circles measurement (including its ABC classification according to displacement) with the coracoclavicular distance and Rockwood types, as well as the semiquantitative degree of DHT, was tested. RESULTS: The circles measurement showed a strong correlation with the coracoclavicular distance according to the Rockwood classification (r = 0.66, P < .001) and differentiated between Rockwood types according to the ABC classification, including types IIIA and IIIB. The circles measurement correlated with the semiquantitative method of assessing DHT (r = 0.61, P < .001). Measurement values were smaller in cases without DHT than in cases with partial DHT (P = .008). Cases with complete DHT had respectively larger measurement values (P < .001). CONCLUSION: In this first in vivo study, the circles measurement allowed differentiation between Rockwood types according to the ABC classification in acute ACJ dislocations with a single measurement and correlated with the semiquantitative degree of DHT. On the basis of these validations of the circles measurement, its use for evaluating ACJ dislocations is recommended.

Does the magnitude of injuries affect the outcome of proximal humerus fractures treated by locked plating (PHILOS)?

PURPOSE: Health-related quality of life (HRQoL) becomes increasingly relevant in an aging society. Functional outcome (FO) and the patient-reported outcome (PRO) after surgical treatment of proximal humerus fractures (PHF) depends on numerous factors, including patient- and injury-specific factors. There is little evidence on how the FO and the PRO vary in different settings such as monotrauma or multiple injuries, even though the PHF is one of the more frequent fractures. In addition, to a previous study, on multiple injured patients and upper extremity injuries, the aim of the current study was to investigate the impact of multiple injuries, quantified by the ISS, on the FO and PRO after surgically treated PHF by PHILOS. METHODS: A retrospective cohort-study was conducted with an additional follow-up by a questionnaire. HRQoL tools such as range of motion (ROM), the Quick-Disability of Arm Shoulder and Hand score (DASH), EuroQol Five Dimension Three Levels (EQ-5D-3L), and EuroQol VAS (EQ-VAS) were used. The study-population was stratified according to ISS obtained based on information at discharge into Group I/M-H (ISS < 16 points) and Group PT-H (ISS ≥ 16). Median outcome scores were calculated and presented. INCLUSION CRITERIA: adult patients (> 18 years) with PHF treated at one academic Level 1 trauma center between 2007 and 2017 with Proximal Humeral Inter-Locking System (PHILOS) and preoperative CT-scan. Group stratification according Injury Severity Score (ISS): Group PT-H (ISS ≥ 16 points) and Group I/M-H (ISS < 16 points). EXCLUSION CRITERIA: oncology patients, genetic disorders affecting the musculoskeletal system, paralysis or inability to move upper extremity prior or after injury, additional ipsilateral upper limb fractures, open injuries, associated vascular injuries as well brachial plexus injuries and nerve damages. Follow-up 5-10 years including PRO: EQ-5D-3L and EQ-VAS. FO, including DASH and ROM. The ROM was measured 1 year after PHILOS. RESULTS: Inclusion of 75 patients, mean age at injury was 49.9 (± 17.6) years. The average follow-up period in Group I/M-H was 6.18 years (± 3.5), and in Group PT-H 5.58 years (± 3.1). The ISS in the Group I/M-H was 6.89 (± 2.5) points, compared to 21.7 (± 5.3) points in Group PT-H (p ≤ 0.001). The DASH-score in Group I/M-H was 9.86 (± 13.12 and in Group PT-H 12.43 (± 15.51, n.s.). The EQ-VAS in Group I/M-H was 78.13 (± 19.77) points compared with 74.13 (± 19.43, n.s.) in Group PT-H. DASH, EQ-VAS as well as ROM were comparable in Groups I/M-H and PT-H (9.9 ± 13.1 versus 12.4 ± 15.5, n.s.). The EQ-5D-3L in Group I/M-H was 0.86 (± 0.23) points compared to Group PT-H 0.72 (± 0.26, p ≤ 0.017). No significant differences could be found in Group I/M-H and PT-H in the severity of traumatic brain injury (TBI). A multivariable regression analyses was performed for DASH, EQ-5D-3L and EQ-VAS. All three outcome metrics were correlated. There was a significant difference between the EQ-5D-3L and the ISS (Beta-Coefficient was 0.86, 95% low was 0.75, 95% high was 0.99, p ≤ 0.041). No significant correlation could be found comparing DASH, EQ-5D-3L and EQ-VAS to age, gender and TBIs. CONCLUSION: Multiple injuries did not affect the DASH, ROM or EQ-VAS after PHILOS; but a higher ISS negatively affected the EQ-5D-EL. While the ROM and DASH aim to be objective measurements of functionality, EQ-5D-3L and EQ-VAS represent the patients' PRO. The FO and PRO outcomes are not substitutable, and both should be taken into consideration during follow-up visits of multiple injured patients. Future research should prospectively explore whether the findings of this study can be recreated using a larger study population and investigate if different FO and PRO parameters come to similar conclusions. The gained information could be used for an enhanced long-term evaluation of patients who suffered a PHF from multiple injuries to meet their multifarious conditions. LEVEL OF EVIDENCE: II.

Arthroscopically Assisted Stabilization of Chronic Acromioclavicular Joint Instability.

This video article demonstrates biological and synthetic acromioclavicular (AC) and coracoclavicular stabilization with use of a hamstring tendon graft and a low-profile TightRope implant (Arthrex). The low-profile TightRope reduces soft-tissue irritation due to knot stacks1. The tendon graft is wrapped around the clavicle and the coracoid to avoid weakening of the osseous structures as a result of clavicular and coracoidal tunnel placement2. Description: For this procedure, the patient is placed in the beach chair position. After establishing standard posterior, anteroinferior, and anterolateral (transtendinous) portals, the arthroscopic preparation of the coracoid base is performed. Next, transcoracoidal-transclavicular drilling is performed, and a nitinol suture passing wire is utilized to aid the placement of the TightRope later in the procedure. The graft passage around the clavicle and the coracoid is then set up by placing 2 additional nitinol suture passing wires. Following this, coracoclavicular stabilization is performed with use of the low-profile TightRope device, after which the graft is shuttled around the clavicle and the coracoid with the help of the passing wires. After the acromial drilling, the graft is shuttled laterally transacromially and subcutaneously back to the clavicle, completing the AC cerclage. Finally, the graft ends are sewn together under tension. The deltotrapezial fascia is closed above the graft, incorporating the tendon ends into the suture. Finally, the skin can be closed. Alternatives: In case of chronic AC joint injuries, many surgical stabilization techniques have been described. On the one hand there are rigid stabilization techniques like the hook-plate or temporary Kirschner wire fixation. On the other hand, there are dynamic stabilization techniques like the modified Weaver-Dunn procedure or solitary synthetic coracoclavicular reconstruction with use of pulley-like devices, with or without additional AC stabilization3. As for nonsurgical alternatives, physiotherapy with periscapular stabilization and muscle strengthening may be an option4. Rationale: For the treatment of chronic AC joint instability, many techniques5-9 have been described that utilized horizontal and vertical stabilization with a tendon graft combined with a synthetic pulley-like device. Usually, multiple transclavicular and transcoracoidal drill holes are utilized for the graft passage, which could weaken the bone and may result in postoperative fractures of the coracoid and clavicle10. Considering this, we present a modified technique that focuses on the optimization of the graft passage. In contrast to other aforementioned techniques, this procedure requires only 1 transcoracoidal-transclavicular tunnel for the TightRope and another transacromial tunnel for the passage of the AC cerclage. By forming a loop of the graft around the coracoid and the clavicle, the graft passage is managed without any additional coracoidal or clavicular drilling. Expected Outcomes: A dedicated study investigating the specific clinical and radiographic results of our technique will be part of future research. Because the biomechanical principle of reconstruction of our technique is very similar to the technique described by Kraus et al., we refer to their clinical and radiographic results regarding the expected outcome. As shown in the chart in the video, Kraus et al. demonstrated good clinical and radiographic results with their biologic and synthetic AC-stabilization technique at a median follow-up of 24 months. The outcomes measured in that study were the Constant score, Subjective Shoulder Value, AC Joint Instability Score, and Taft score. Patients were divided into 2 groups. Group 1 included patients with failed prior conservative treatment, and group 2 included those with failed prior surgical treatment. Overall, the authors report complete dynamic posterior translation in 1 patient and partial dynamic posterior translation in 5 patients. Although there was no notable enlargement of the TightRope drill hole, the authors of that study found a significant enlargement of the clavicular graft tunnels. However, the enlargement had no clinical relevance10. Important Tips: Utilize a low-profile TightRope device to minimize the risk of suture irritation from knot stacks.The tendon graft should be ≥24 cm in length. If the graft is too short, perform an end-to-end anastomosis of 2 grafts.Utilize an image intensifier to ensure correct drill hole placement and avoid damage to neurovascular structures.The graft passage around the clavicle and the coracoid can be dilated by hand with the use of differently sized drill bits.Incorporate the graft into fascial closure at the end of the procedure.