Sagittal orientation of coracoclavicular ligament reconstruction affects the stability of surgical repair.

BACKGROUND: The variation in the anatomic relationship between the coracoid and the clavicle affects the biomechanical stability of coracoclavicular ligament reconstruction (CCLR). METHODS: Three-dimensional computed tomography reconstruction of 85 patients was analyzed. Anatomic landmarks were used to derive the coracoclavicular sagittal reconstruction angle (sRA). The lateral concave angle, which indicated the shape of the distal clavicle, and the offsets between the clavicle and coracoid were also measured. To investigate the biomechanical effects of the sRA on CCLR, 7 computed tomography scans with different sRAs were 3D printed. Two reconstructions, a single trans-coracoclavicular tunnel and a looped reconstruction technique, were performed sequentially. Models were cyclically loaded at 70 N in the anterior, posterior, and superior directions. RESULTS: The mean sRA was 68° ± 9.3° (range, 47°-85°). The superoinferior offset between the clavicle and the coracoid and the lateral concave angle positively correlated with the sRA (r = 0.359 and 0.837, respectively; P ≤ .001), whereas the anteroposterior offset had a negative correlation (r = -0.925; P < .001). The sRA had a negative correlation with the anterior displacement of the clavicle (rho = -0.96; P < .001) and a positive correlation with the posterior displacement for both surgical techniques (rho = 1.0; P < .001). CONCLUSION: The anatomic orientation of the native coracoclavicular ligaments is highly variable in the sagittal plane. Low sagittal angles can reduce anterior stability, whereas high sagittal angles can reduce posterior stability of CCLR.

Acromioclavicular joint augmentation at the time of coracoclavicular ligament reconstruction fails to improve functional outcomes despite significantly improved horizontal stability.

PURPOSE: Acromioclavicular joint reconstruction is a well-established and frequently performed procedure. Recent scientific and commercial interest has led to a drive to develop and perform surgical techniques that more reliably restore horizontal stability in order to improve patient outcomes. The aim of this systematic review was to evaluate the biomechanical evidence for procedures directed at restoring horizontal stability and determine whether they are associated with superior clinical results when compared to well-established procedures. METHODS: A review of the online databases Medline and EMBASE was conducted in accordance with the PRISMA guidelines on the 23rd December 2017. Biomechanical and clinical studies reporting either static or dynamic horizontal displacement following acromioclavicular joint reconstruction (Coracoclavicular reconstruction or Weaver-Dunn) were included. In addition, biomechanical and clinical studies reporting outcomes after additional augmentation of the acromioclavicular joint were included. The studies were appraised using the Methodological index for non-randomised studies tool. RESULTS: The search strategy identified 18 studies eligible for inclusion: six biomechanical and 12 clinical studies. Comparative biomechanical studies demonstrated that acromioclavicular augmentation provided significantly increased horizontal stability compared to the coracoclavicular reconstruction and Weaver-Dunn procedure. Comparative clinical studies demonstrated no significant differences between coracoclavicular reconstruction with and without acromioclavicular augmentation in terms of functional outcomes (American Shoulder and Elbow Surgeon and Constant score), complication or revision rates. However, one comparative study did demonstrate an improvement in Taft (p = 0.018) and Acromioclavicular Joint Instability scores (p = 0.0001) after acromioclavicular augmentation. CONCLUSION: In conclusion, coracoclavicular reconstruction with augmentation of the acromioclavicular joint has been shown to provide improved horizontal stability in both biomechanical and clinical studies compared to isolated coracoclavicular reconstruction. However, comparative studies have shown no clinical advantage with respect to American Shoulder and Elbow Surgeon or Constant scores and, therefore, the results of this systematic review do not support acromioclavicular augmentation in routine clinical practice. LEVEL OF EVIDENCE: IV.

An In Vitro Study Demonstrating the Significance of Acromioclavicular Ligament Repair in Restoring Horizontal and Rotational Acromioclavicular Joint Stability.

BACKGROUND: The principle of joint reconstruction surgery is to try to recreate the native joint biomechanics and stability. With respect to acromioclavicular joint (ACJ) surgery, much focus to date has been on restoring the superoinferior stability. There is concern that persistent horizontal instability following ACJ reconstruction could lead to poorer patient outcomes; therefore, we evaluated whether acromioclavicular (AC) ligament repair offers improved horizontal stability in conjunction with ACJ reconstruction. METHODS: A whole-body human cadaver was used. The ACJ was exposed and subjected to a constant 70N load on the lateral end of the clavicle to test the anteroposterior (AP), superoinferior (SI), and horizontal pivot angle (HPA) around the ACJ. The AC and coracoclavicular (CC) ligaments were subsequently divided, and the above three parameters were re-tested. Ligament augmentation and reconstruction system (Corin Group, Cirencester, UK), LockDown (LockDown Medical Limited, Redditch, UK), Endobutton (Smith and Nephew Inc., London, UK), and Neoligament implant (Xiros Ltd., Leeds, UK) were used to reconstruct the CC ligaments and tested with and without AC repair. RESULTS: The native ACJ allowed an average 2.48 mm AP and 3.88 mm SI translation with a 27° HPA. All synthetic implants significantly improved the vertical stability of the ACJ but allowed up to a four-fold increase in AP translation. Coupled with ACJ repair, all the reconstructions were far superior, especially in restoring horizontal stability. CONCLUSION: The implants varied in their approach to fixation and concentrated primarily on the reconstruction of CC ligaments. Our study was able to demonstrate that AC repair significantly improves the stability of the construct and significantly reduces vertical and horizontal instability.

Modified Weaver Dunn Versus Ligamentous Reconstruction Grafts in Chronic Acromioclavicular Joint Dislocation: A Systematic Review and Meta-Analysis of Comparative Studies.

Background: Acromioclavicular (AC) joint trauma is a frequent sports injury. Modified Weaver Dunn (MWD) is a commonly used technique to address this injury. However, tendinous grafts (Autogenous Palmaris Longus or Semitendinosus tendons) are increasingly being used due to the biologic weakness of MWD. Methods: Three search was done until January 2024 with data extraction consisting of adverse events (infections and failures), Constant-Murley score, American Shoulder and Elbow Surgeons score, and postoperative coracoclavicular distance. Results: Four studies were included in this metaanalysis. Tendinous graft was shown to have statistically better ASES and Constant-Murley scores. Furthermore, there were no difference in adverse events, and postoperative coracoclavicular distance. Conclusion: The tendinous graft showed no differences in adverse events, and postoperative coracoclavicular distance when compared to modified Weaver Dunn. However, it showed higher postoperative ASES and Constant-Murley score without analysis of the minimal clinical important difference making the difference solely statistical. Level of evidence: 3.

[Restoring horizontal stability in III-V acromioclavicular dislocations by anatomic reconstruction of the coracoclavicular and acromioclavicular ligaments; surgical technique]. / Restablecimiento de la estabilidad horizontal en luxaciones acromioclaviculares III-V mediante la reconstrucción anatómica de los ligamentos coracoclaviculares y acromioclaviculares; técnica quirúrgica.

INTRODUCTION: dislocation of the acromioclavicular (AC) joint is a common injury seen in young adults. The objective is to describe a surgical technique that can restore the horizontal and vertical stability of the AC joint. MATERIAL AND METHODS: we describe a surgical technique that can restore horizontal and vertical stability using an allograft for the anatomical reconstruction of the CC and AC ligaments, for AC grade III-V dislocations according to the Rockwood classification. RESULTS: this is a surgical technique with anatomical and biological reconstruction of the CC and AC ligaments, using an allograft. Two bone tunnels are made in the clavicle, passing the lateral end of the graft below the acromion; then the two ends are fixed with two bioabsorbable screws, restoring vertical and horizontal stability. CONCLUSION: this procedure allows to restore the vertical and horizontal stability of the AC joint. Follow up studies are required to report functional and radiological results, in order to ensure advantages compared to existing techniques.

INTRODUCCIÓN: la luxación de la articulación acromioclavicular (AC) es una lesión frecuente que se observa en adultos jóvenes. El objetivo es describir una técnica quirúrgica que pueda restablecer la estabilidad horizontal y vertical de la articulación AC. MATERIAL Y MÉTODOS: se describe una técnica quirúrgica utilizando un aloinjerto para la reconstrucción anatómica de los ligamentos coracoclaviculares (CC) y AC para luxaciones AC grado III-V de acuerdo con la clasificación de Rockwood. RESULTADOS: es una técnica quirúrgica con reconstrucción anatómica y biológica de los ligamentos CC y AC con injerto. Se realizan dos túneles óseos en la clavícula pasando el cabo lateral del injerto por debajo del acromion; posteriormente se fijan los dos cabos con dos tornillos bioabsorbibles, restaurando de esta manera la estabilidad vertical y horizontal. CONCLUSIÓN: este procedimiento permite restablecer la estabilidad vertical y horizontal de la articulación AC. Se requieren estudios de seguimiento para reportar resultados funcionales y radiológicos con el fin de poder asegurar ventajas en comparación con las técnicas existentes.

Acromioclavicular Joint Separation: Repair Through Suture Anchors for Coracoclavicular Ligament and Nonabsorbable Suture Fixation for Acromioclavicular Joint.

OBJECTIVE: To evaluate the clinical and radiographic outcomes of patients undergoing coracoclavicular (CC) ligament repair by two suture anchors and acromioclavicular (AC) joint (ACJ) fixation using heavy nonabsorbable sutures for the treatment of types III-V ACJ injuries with a minimum of 1-year follow-up. METHODS: The clinical and radiographic outcomes of 36 consecutive patients (26 men and 10 women) who underwent anatomic reduction for acute ACJ dislocation using two suture anchors for CC ligament reconstruction and two strands of non-absorbable stitches for ACJ fixation between December 2013 and December 2018 were reviewed. Two 3.5 mm suture anchors with double-loaded sutures were separately inserted into the anterolateral and posteromedial portions of the coracoid process. The suture strands were passed through the hole created in the clavicle using 2.0 mm drill and tied over the clavicle. Additional ACJ augmentation using two strands of non-absorbable heavy sutures was performed in all patients. At 3, 6, and 12 months and last follow-up visit, the scores on the visual analog scale (VAS), the American Shoulder and Elbow Surgeons (ASES) score, Constant-Murley score, and simple shoulder test (SST) questionnaires were used to provide a final evaluation of shoulder function. Comparison between baseline and treatment results was performed. Radiographic analysis included vertical displacement and horizontal shift. RESULTS: A total of 29 patients (20 men and nine women) were included in the study. A total of seven, six, and 16 patients had Rockwood type III, type IV, and type V ACJ dislocations, respectively. The mean patient age was 42.8 ± 13.5 years, with a mean follow-up of 28 months (range, 12-56 months). At the 12-month follow-up, the mean ASES score was 92.1 ± 3.5, with a mean pain score of 0.5 ± 0.7 on the VAS and mean Constant-Murley score of 93.0 ± 2.4. The new number of positive answers on the SST was 11.5 ± 0.6. Compared with the baseline, the clinical results improved significantly (P < 0.05). No significant difference could be found between the 6- and 12-month follow-up evaluations (P > 0.05). Radiographs showed two partial loss of reduction, whereas no horizontal displacement was found in all patients. One patient developed a superficial wound infection 3 weeks postoperation. The wound healed after routine wound care. No neurovascular complications were recorded. CONCLUSIONS: CC ligament reconstruction using two suture anchors and ACJ augmentation using two strands of non-absorbable heavy sutures on high-grade AC dislocation is a reliable technique for restoring stability to the ACJ and can obtain good to excellent clinical results.

Chronic acromioclavicular dislocations: multidirectional stabilization without grafting.

OBJECTIVE: Clinical and radiological evaluation of the surgical treatment of chronic acromioclavicular (AC) dislocations with triple button device and AC joint augmentation. MATERIALS AND METHODS: This retrospective study included 21 patients with chronic AC dislocations. All patients underwent bilateral-weighted Zanca and Alexander views as well as the Constant score (CS) and Acromioclavicular Joint Instability Scoring System (ACJI). RESULTS: A total of 21 patients (19 men and 2 women) with the mean age of 30.7 ± 11.7 years (range, 19-62 years) were able to participate in clinical and radiographic follow-up. After a mean follow-up of 49.7 ± 17.1 months (range, 13-60 months), the results of the CS were 95.2 ± 5.5 (range, 85-100) and ACJI test 89.7 ± 7.9 (range, 75-100), showing no significant differences with the uninjured shoulder (CS, 96.2 ± 3.9; range, 85-100; ACJI, 95.7 ± 4.1; range, 85-100). At the final review, we observed that the preoperative coracoclavicular distance (Zanca view) improved from 12.8 ± 1.5 mm to 8.5 ± 1.3 mm and the AC distance (Alexander view) from 7.8 ± 2.3 mm to 0.99 ± 0.91 mm. Compared with healthy shoulder, these differences were not significant. Osteoarthritis or radiological calcifications were not associated with worse clinical outcomes. CONCLUSION: The triple button device is an acceptable alternative surgical method for chronic AC joint dislocations. The surgical technique is simple; it does not need a graft, nor does it present major complications, and material extraction is unnecessary.

Biplanar fixation of acromio-clavicular joint dislocation associated with coracoid process fracture: Case report.

INTRODUCTION: Acromioclavicular (AC) joint injury associated with coracoid process (CP) fracture is a rare injury and only case reports had been published in the literature. Although AC joint injury is not uncommon, there is controversy as regard the best stabilization method whether to use wires, hook plate, arthroscopic reconstruction or the recently described techniques of anatomic restoration of both the coracoclavicular (CC) and acromioclavicular (AC) ligaments to add stability in both the vertical as well as the horizontal plane for the AC joint. Isolated CP fracture rarely necessitates surgical intervention; but in association with AC joint injury; a controversy as regard best management, surgical approach, technique of stabilization and implant used is present due to paucity of literature. PATIENT AND METHOD: A 36 years old manual worker who sustained a combined injury of AC joint (grade III) and CP comminuted base fracture had been treated surgically in our hospital using a biplanar fixation technique; blind 4 mm cannulated screw for the CP fracture and anatomic reconstruction of the AC ligament using FibreTape (Arthrex, Naples, FL); to add stability in both the vertical and horizontal plane. Follow up was done for one year. RESULTS: After completion of rehabilitation program, patient could return to work with no shoulder pain in ten weeks postoperatively. Till the last follow up there was no evidence of loss of reduction or shoulder pain with a Constant score of 86. CONCLUSION: Our technique in combined AC joint and CP fracture, address both injuries to add biplanar AC joint stability allowing accelerated rehabilitation and avoids metal hardware complications.

Restablecimiento de la estabilidad horizontal en luxaciones acromioclaviculares III-V mediante la reconstrucción anatómica de los ligamentos coracoclaviculares y acromioclaviculares; técnica quirúrgica / Restoring horizontal stability in III-V acromioclavicular dislocations by anatomic reconstruction of the coracoclavicular and acromioclavicular ligaments; surgical technique

Resumen: Introducción: la luxación de la articulación acromioclavicular (AC) es una lesión frecuente que se observa en adultos jóvenes. El objetivo es describir una técnica quirúrgica que pueda restablecer la estabilidad horizontal y vertical de la articulación AC. Material y métodos: se describe una técnica quirúrgica utilizando un aloinjerto para la reconstrucción anatómica de los ligamentos coracoclaviculares (CC) y AC para luxaciones AC grado III-V de acuerdo con la clasificación de Rockwood. Resultados: es una técnica quirúrgica con reconstrucción anatómica y biológica de los ligamentos CC y AC con injerto. Se realizan dos túneles óseos en la clavícula pasando el cabo lateral del injerto por debajo del acromion; posteriormente se fijan los dos cabos con dos tornillos bioabsorbibles, restaurando de esta manera la estabilidad vertical y horizontal. Conclusión: este procedimiento permite restablecer la estabilidad vertical y horizontal de la articulación AC. Se requieren estudios de seguimiento para reportar resultados funcionales y radiológicos con el fin de poder asegurar ventajas en comparación con las técnicas existentes.

Abstract: Introduction: dislocation of the acromioclavicular (AC) joint is a common injury seen in young adults. The objective is to describe a surgical technique that can restore the horizontal and vertical stability of the AC joint. Material and methods: we describe a surgical technique that can restore horizontal and vertical stability using an allograft for the anatomical reconstruction of the CC and AC ligaments, for AC grade III-V dislocations according to the Rockwood classification. Results: this is a surgical technique with anatomical and biological reconstruction of the CC and AC ligaments, using an allograft. Two bone tunnels are made in the clavicle, passing the lateral end of the graft below the acromion; then the two ends are fixed with two bioabsorbable screws, restoring vertical and horizontal stability. Conclusion: this procedure allows to restore the vertical and horizontal stability of the AC joint. Follow up studies are required to report functional and radiological results, in order to ensure advantages compared to existing techniques.

Acute high-grade acromioclavicular dislocations treated with triple button device (MINAR): Preliminary results.

OBJECTIVE: Describe the clinical and radiological results of triple button device in the treatment of high-grade AC dislocations (Rockwood, type V) and assess whether improves vertical and horizontal stability compared to the techniques previously described. MATERIAL AND METHODS: This retrospective study included 39 patients with type V acromioclavicular dislocations treated with Twin Tail TightRope™ system (triple button device). Of the 39 patients, 33 (26 men and 7 women) were able to participate in clinical and radiographic follow up. At the time of surgery, the mean age was 25years±7(range, 17-49). All patients underwent bilateral-weighted Zanca (CC distance) and Alexander view (AC distance) as well as the Constant Score (CS) and Acromioclavicular Joint Instability Scoring System (ACJI). Radiological and clinical outcome was assessed during routine follow-up examinations preoperatively, postoperatively, 1, 3, 6 months and every year after the surgery. The presence of calcification, degenerative changes, mobilization of implants and bone resorption were also assessed. RESULTS: After a mean follow up of 25±4months (range 14-38), the results of the Constant (CS) were 94.1±5,5 (range 76-100) and test ACJI 87.3±9,8 (range 65-100), showing no significant differences with the uninjured shoulder (CS 95.8±2.5, range 83-100; ACJI 94.1±3.7, range 80-100). At final review, we observed that preoperative coracoclavicular distance (Zanca View) improved from 21,75±1.97mm to 8,73mm±0.75 and the acromioclavicular distance (Alexander View) from 12,65mm±1.99 to 0,35±0.3mm. Compared with healthy shoulder, these differences were not significant. There was no loss of reduction with this system in the vertical plane. 4 patients (12.12%) revealed signs of posterior instability with worse clinical test results. The presence of degenerative joint changes (6,06%), calcifications (27,2%) or mobilization of the implant (18,18%) was not associated with worse clinical outcomes. CONCLUSION: Twin Tail device using minimally invasive technique improves stability in the vertical and, specially in the horizontal plane relative to the previously described techniques without increasing number of complications.