Anatomic considerations of transclavicular-transcoracoid drilling for coracoclavicular ligament reconstruction

Arthroscopy-assisted procedure provides less residual horizontal instability and optimal coracoid tunnel creation with less radiation exposure compared to percutaneous procedure after endo-button fixation of type III AC joint dislocations

PURPOSE

The aim of this study was to evaluate the postoperative radiological and functional results of patients treated with arthroscopy-assisted (AA) and percutaneous (P) procedures using endo-button for type III acromioclavicular joint dislocations with a minimum 1-year follow-up. The study hypothesis was that the AA technique would provide more favourable coracoid tunnels.

METHODS

This retrospective study included patients who underwent surgery between 2017 and 2022. Computed tomography images taken immediately postoperatively of all the patients were analysed to group coracoid tunnels as optimal or suboptimal based on orientation and placement within the coracoid base. Residual horizontal instability was assessed using the bilateral Alexander view at the final follow-up. Shoulder functions were evaluated at the final follow-up examination.

RESULTS

Of the 63 patients, 39 underwent surgery using the percutaneous procedure and 24 with the AA procedure. Surgical duration was significantly longer in the AA group (AA: 61.1 ± 5.9 min; P: 34.7 ± 5.6 min) (p = 0.001; 95% confidence interval [CI]: 23.3-29.3), whereas fluoroscopy time was longer in the percutaneous group (AA: 2.0 ± 0.8 s; P: 15.7 ± 3.9 s) (p = 0.001; 95% CI: -14.9 to 12.3). Optimal coracoid tunnels were more frequently observed in the AA group (p = 0.001; 95% CI: 7.4-137.8). There was no significant difference in functional scores between the groups (n.s.). Postoperative horizontal instability was more common in the percutaneous procedure (p = 0.013; 95% CI: 8.3-39.2).

CONCLUSIONS

Although no difference was detected between the methods in terms of complications and functional results, the higher frequency of residual horizontal instability, the high risk of suboptimal tunnel creation and greater radiation exposure were seen to be the most important disadvantages of the percutaneous technique. During surgery, such technical problems related to the percutaneous method should be kept in mind and care should be taken about the orientation of the coracoid tunnel.

LEVEL OF EVIDENCE

Level III.

Functional reconstruction of chronic acromioclavicular joint separation using a double suture technique combined with semitendinosus autograft

PURPOSE

We present the functional and clinical results of a combined surgical technique that functionally restores chronic Acromioclavicular Joint Instability (AJI). The method combines a double-looped suture fixation augmented with a semitendinosus autograft.

METHODS

Between 2017 and 2021, 15 patients were treated using the surgical technique. All patients suffered an Acromioclavicular Joint Separation that remained untreated for at least 6 (6-16) weeks after the initial injury. Four Ethibond sutures were passed below the coracoid process and through a 4.5 drill hole in the clavicle. The sutures provided adequate horizontal and vertical reduction and stabilization of the clavicle. A semitendinosus autograft was passed below the coracoid process and looped around the clavicle. The remaining graft limbs were used to reconstruct the acromioclavicular capsule. Patients were radiologically evaluated with bilateral anteroposterior (AP), Zanca, and Alexander views. The clinical evaluation was based on the Acromioclavicular Joint Instability Score and the Constant-Murley Score.

RESULTS

The mean follow-up period was 31.2 months (17-61). The mean last ACJIS and CMS scores were 96 (90-100) and 97.67 (87-100), respectively. Reduction of the clavicle was radiologically confirmed in all cases throughout the follow-up period. AC arthritis was reported in 1 case without associated clinical symptoms. No significant complications were reported, and all patients returned to the pre-injury activity level.

CONCLUSION

The presented functional reconstruction of the AC joint disruption in chronic cases is an effective and secure method with low complication rates and good clinical results.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Transcoracoid Drilling for Coracoclavicular Ligament Reconstructions in Patients With Acromioclavicular Joint Dislocations Result in Eccentric Tunnels

Purpose

To determine the location of coracoid inferior tunnel exit with superior-based tunnel drilling and coracoid superior tunnel exit with inferior-based tunnel drilling.

Methods

Fifty-two cadaveric embalmed shoulders (mean age 79 years, range 58-96 years) were used. A transcoracoid tunnel was drilled at the center of the base. Twenty-six shoulders were used for the superior-to-inferior tunnel drilling approach and 26 shoulders for the inferior-to-superior tunnel drilling approach. The distances to the margins of the coracoid process, from both the entry and exit points of the tunnel, were measured. Paired Student t-tests were used to compare the distance from the center of the tunnel and the medial and lateral coracoid border and the apex.

Results

The mean difference for the distances between superior entry and inferior exit from the apex was 3.65 ± 3.51 mm (P = .002); 1.57 ± 2.27 mm for the lateral border (P = .40) and 5.53 ± 3.45 mm for the medial border (P = .001). The mean difference for the distances between inferior entry and superior exit from the apex was 16.95 ± 3.11 mm (P = .0001); 6.51 ± 3.2 mm for the lateral border (P = .40) and 1.03 ± 2.32 mm for the medial border (P = .045). Inferior-to-superior drilling resulted in 4 (15%) cortical breaks.

Conclusions

Both superior-to-inferior and inferior-to-superior tunnel drilling directed the tunnel from a more anterior and medial entry to a posterior-lateral exit. Superior-to-inferior drilling resulted in a more posteriorly angled tunnel. When using a 5-mm reamer and inferior-to-superior tunnel drilling, cortical breaks were observed at the inferior and medial margin of the tunnel exit.

Clinical Relevance

Arthroscopic-assisted acromioclavicular joint reconstruction using conventional jigs may result in an eccentric coracoid tunnel, possibly introducing stress risers and fractures. To avoid cortical breaks and eccentric tunnel placement, open drilling from superior-to-inferior with a superiorly centered guide pin and arthroscopic visualization of a centered inferior exit should be considered.

Evaluation of the coracoid bone tunnel placement on Dog Bone™ button fixation for acromioclavicular joint dislocation: a cadaver study combined with finite element analysis

BACKGROUND

Dog Bone™ button fixation is frequently used to treat acromioclavicular joint (ACJ) dislocation. However, various studies have reported complications after fixation.

OBJECTIVE

To investigate the effect of the coracoid bone tunnel location on the treatment of ACJ dislocation through single-tunnel coracoclavicular (CC) ligament fixation with the Dog Bone™ button.

METHODS

Six cadaveric shoulders were used. Each specimen was subjected to five testing conditions in the following order: (1) normal ACJ (Gn); (2) acromioclavicular and CC ligaments were removed (G0); (3) CC ligament reconstruction was performed using the Dog Bone™ technique, and the coracoid bone tunnel was at the center of the coracoid base (G1); (4) reconstruction was performed at 5 mm distal from the G1 site, along the axis of the coracoid (G2); (5) reconstruction was performed at 10 mm distal from the G1 site, along the axis of the coracoid (G3). The angles of pronation and supination of the clavicle under the same load (30 N) were measured. Next, a finite element (FE) model was created using computed tomography (CT) images of the normal shoulder. Model 1 (M1), model 2 (M2), and model 3 (M3) correspond to G1, G2, and G3, respectively. A force of 70 N was applied as a vertical upward load to the distal clavicle. Subsequently, the von Mises stress, the strain LE along the FiberWire, and the displacement nephogram of the three models were obtained.

RESULTS

After single-tunnel CC ligament fixation using the Dog Bone™ technique, the clavicle in the G2 group (20.50 (19.50, 21.25) °, 20.00 (18.75, 21.25) °) had the best rotational stability. The peak von Mises stress, the strain LE along the FiberWire, and the maximum displacement were smaller in M2 than in M1 and M3.

CONCLUSIONS

When the coracoid bone tunnel was located 5 mm anterior to the center of the coracoid base (along the axis of the coracoid), the clavicle showed greater rotational stability.

Bone tunnel placement influences shear stresses at the coracoid process after coracoclavicular ligament reconstruction: a finite element study and radiological analysis

INTRODUCTION

Coracoid fractures after arthroscopic treatment of acromioclavicular (AC) joint separations lead to poor clinical outcomes. In this study, different configurations of bone tunnels in the lateral clavicle and coracoid were examined concerning the amount of stress induced in the coracoid.

METHODS

An authentic 3D finite element model of an ac joint was established. Three 2.4 mm bone tunnels were inserted in the lateral clavicle, which were situated above, medially and laterally of the coracoid. Then, two 2.4 mm bone tunnels were inserted in the latter, each simulating a proximal and a distal suture button position. Von Mises stress analyses were performed to evaluate the amount of stress caused in the coracoid process by the different configurations. Then, a clinical series of radiographs was examined, the placement of the clavicle drill hole was analyzed and the number of dangerous configurations was recorded.

RESULTS

The safest configuration was a proximal tunnel in the coracoid combined with a lateral bone tunnel in the clavicle, leading to an oblique traction at the coracoid. A distal bone tunnel in the coracoid and perpendicular traction as well as a proximal tunnel in the coracoid with medial traction caused the highest stresses. Anatomical placement of the clavicle drill hole does lead to configurations with smaller stresses.

CONCLUSION

The bone tunnel placement with the smallest amount of shear stresses was found when the traction of the suture button was directed slightly lateral, towards the AC joint. Anatomical placement of the clavicle drill hole alone was not sufficient in preventing dangerous configurations.

LEVEL OF EVIDENCE

Controlled laboratory study.

Current concepts in acromioclavicular joint (AC) instability - a proposed treatment algorithm for acute and chronic AC-joint surgery

BACKGROUND

There exists a vast number of surgical treatment options for acromioclavicular (AC) joint injuries, and the current literature has yet to determine an equivocally superior treatment. AC joint repair has a long history and dates back to the beginning of the twentieth century.

MAIN BODY

Since then, over 150 different techniques have been described, covering open and closed techniques. Low grade injuries such as Type I-II according to the modified Rockwood classification should be treated conservatively, while high-grade injuries (types IV-VI) may be indicated for operative treatment. However, controversy exists if operative treatment is superior to nonoperative treatment, especially in grade III injuries, as functional impairment due to scapular dyskinesia or chronic pain remains concerning following non-operative treatment. Patients with a stable AC joint without overriding of the clavicle and without significant scapular dysfunction (Type IIIA) may benefit from non-interventional approaches, in contrast to patients with overriding of the clavicle and therapy-resistant scapular dysfunction (Type IIIB). If these patients are considered non-responders to a conservative approach, an anatomic AC joint reconstruction using a hybrid technique should be considered. In chronic AC joint injuries, surgery is indicated after failed nonoperative treatment of 3 to 6 months. Anatomic AC joint reconstruction techniques along with biologic augmentation (e.g. Hybrid techniques, suture fixation) should be considered for chronic high-grade instabilities, accounting for the lack of intrinsic healing and scar-forming potential of the ligamentous tissue in the chronic setting. However, complication and clinical failure rates remain high, which may be a result of technical failures or persistent horizontal and rotational instability.

CONCLUSION

Future research should focus on addressing horizontal and rotational instability, to restore native physiological and biomechanical properties of the AC joint.

An Accuracy Comparison of Minimally Invasive Transclavicular-Transcortical Drilling with Free-Hand, C-Shape and Assembly-Type Guide Device: An In Vitro Study

OBJECTIVES

Ensuring the accuracy of transclavicular-transcoracoid drilling in the anatomical reconstruction of the coracoclavicular ligament complex with minimally invasive incisions remains a major problem for inexperienced surgeons. The purpose of this study was to design an assembly guide device for transclavicular-transcoracoid drilling with minimally invasive incisions, to manufacture the finished product, and to compare its feasibility and accuracy with the existing C-shape guide devices and free-hand techniques.

METHODS

An assembly-type guide device was designed and produced using computer-aided design and three-dimensional printing. The specimen data of 54 human shoulders from 27 gross specimen (14 males and 13 females) treated by free-hand drilling, C-shape device drilling, and assembly-type guide device drilling from October 2018 to January 2021 were analyzed in a controlled laboratory study. Fifty-four human shoulder specimens were randomly assigned into free-hand (n = 18), C-shape (n = 18), and assembly (n = 18) groups by drawing lots for transclavicular-transcoracoid drilling by three inexperienced surgeons. After the drilling procedure was completed and the devices were removed, the operation outcomes were assessed and evaluated. Distances from the tunnel edge to the coracoid's medial (d_m ) and lateral (d_l ) edges, operation time, and tunnel location zones on the coracoid's inferior surface of all specimens in the three groups were measured to evaluate the surgical accuracy and efficiency.

RESULTS

All specimens in the three groups completed the drilling operation successfully and were correctly measured. The distance differences (d_d ) between d_m and d_l in the free-hand, C-shape, and assembly groups were 3.2 ± 1.8 mm, 1.8 ± 1.0 mm, 1.0 ± 0.8 mm, respectively. The d_d of the free-hand group was higher than that of the other two groups (p < 0.001). The tunnel exit points on the inferior coracoid surface located in undesired zones were six (33%), one (6%), and zero in the free-hand group, C-shape group, and assembly-type group, respectively (p = 0.012). The operation time in the free-hand, C-shape, and assembly groups were 198 ± 36 s, 256 ± 64 s, and 353 ± 88 s, respectively. The operation time of each group significantly differed from that of the others (p < 0.001).

CONCLUSION

The assembly-type devices may be the first choice for inexperienced surgeons while both the C shape devices and assembly-type guide devices achieved higher accuracy than free-hand techniques.

Computed Tomography‐Based Determination of the Optimal Locations of Bone Tunnels for Coracoclavicular Ligament Reconstruction

Objective

An agreement has not been reached on optimal locations of bone tunnels for coracoclavicular ligament (CCL) reconstruction for acromioclavicular joint dislocation (ACD). This study aims to identify the convergence point (cP) between the coracoid process and clavicle in the Chinese population to assist surgeons in reconstructing the CCL for ACD.

Methods

From 2014 to 2020, 483 CT scans of the shoulders of 270 male and 213 female patients (247 right and 236 left shoulders) were collected and studied retrospectively. By overlapping the images of the transverse plane of the coracoid process and the clavicle, points a and b, and the midpoint ab (cP) were determined. Then, a series of parameters through point cP in the transverse and sagittal planes were measured. In the transverse plane this included the distance from point cP to the tip of the coracoid process (cP‐cor),the distance between the medial and lateral margins of the coracoid process through point cP (Med‐lat cor), the distance from point cP to the acromioclavicular joint (cP‐ac), and the distance between the anteroposterior margin of the clavicle through point cP (Ap‐clav). In the sagittal plane, this included the craniocaudal segment of the coracoid process (Cc‐cor), and the craniocaudal segment of the clavicle (Cc‐clav). The sex and side differences of these measurements were also analyzed by two radiologists.

Results

Based on the following measurements, point cP was determined. For male patients, the cP‐cor was 28.02 ± 3.43 mm, Med‐lat cor was 22.78 ± 2.80 mm, Cc‐cor was 15.11 ± 2.13 mm, cP‐ac was 29.24 ± 3.84 mm, Ap‐clav was 18.27 ± 2.46 mm, and Cc‐clav was 10.09 ± 1.56 mm. For female patients, the cP‐cor was 25.20 ± 3.26 mm, Med‐lat cor was 20.21 ± 2.97 mm, Cc‐cor was 13.03 ± 1.77 mm, cP‐ac was 26.66 ± 3.45 mm, Ap‐clav was 16.10 ± 2.30 mm, and Cc‐clav was 8.91 ± 1.40 mm. All the measurements of female patients were lower than those of male patients (p < 0.01). Between sides, only cP‐ac of the left shoulders was significantly lower than those of the right shoulders (p < 0.05), with no significant differences in other parameters between sides (p > 0.05).

Conclusion

The results of this study identified the locations of bone tunnel‐cP in the coracoid process and clavicle for the CCL reconstruction in ACD. Moreover, the findings indicated that surgeons should be more cautious in operating on female patients and that the cP‐ac of left shoulders should be set lower than that of right shoulders.

Addition of Allograft and Acromioclavicular Cerclage Improves Outcomes of Arthroscopic-Assisted Reconstruction of Acromioclavicular Separation With a Single Coracoclavicular Tunnel

Objective

The purpose of this study was to prospectively evaluate the functional outcome and complications of unstable acromioclavicular (AC) joint separations repaired with a single coracoclavicular tunnel utilizing an arthroscopic-assisted curved button technique.

Methods

Thirty-five patients with a minimum of 12 months follow-up underwent arthroscopic-assisted AC joint reconstruction with suspensory button and 2 mm suture tape fixation using 3 mm tunnels. Functional outcome scores were analyzed preoperatively and at final follow-up with all complications noted.

Results

Comparing preoperative to postoperative values, all functional outcome scores improved. Three of the 16 (19%) patients that had a supplementary graft looped around the undersurface of the coracoid demonstrated loss of reduction compared to eight of the 19 (42%) that were treated with button and suture fixation alone (p = .138). No loss of reduction occurred in the subset of patients with AC joint supplementation. One (3%) patient sustained a distal clavicle fracture.

Conclusion

Arthroscopic-assisted AC joint reconstruction with a suspensory button construct demonstrates improved clinical outcomes with high patient satisfaction. While loss reduction remains problematic, smaller bone tunnels appear to lead to a low rate of iatrogenic fractures. The addition of a free tendon graft, as well as AC cerclage, appears to minimize loss of reduction.

Arthroscopically assisted single tunnel reconstruction for acute high-grade acromioclavicular joint dislocation with an additional acromioclavicular joint cerclage

PURPOSE

Purpose of this study was to demonstrate that a single tunnel reconstruction of high-grade acromioclavicular (AC) joint instabilities with implants of the second generation is sufficient for stabilisation, especially in combination with an AC cerclage.

METHODS

Patients with an acute AC-joint dislocation type Rockwood III-B and V were included. Besides clinical follow-up examination, radiographs were analysed. The functional outcome measures were Constant Score (CS), Taft score (TS), ACJI score and patient's satisfaction. Horizontal instability was evaluated by clinical examination and radiological with an Alexander view.

RESULTS

Thirty-five patients with a mean follow-up of 29 months were included. Ninety-seven per cent were satisfied with their result, with an average Subjective Shoulder Value of 90%. The CS averaged at 90 ± 10 points, TS at 11 ± 1 points and ACJI at 78 ± 18 points. Radiologically, 3 of 29 patients (10%) showed a persisting horizontal instability. The coracoclavicular (CC) distance improved from 22 preoperative to 10 mm postoperative, which was comparable to the contralateral side (10 mm, p = 0.103). At follow-up the CC distance increased to 13 mm (p = 0.0001).

CONCLUSION

AC-joint stabilisation with a single tunnel reconstruction using a second-generation implant results in good to excellent clinical results with high patient satisfaction. The additional AC augmentation improves stability in horizontal instable AC-joints and is recommended in all high-grade AC joint stabilisations. Nonetheless, reduction was slightly lost over time due to an elongation or suture failure of the coraco-clavicular fixation.

LEVEL OF EVIDENCE

IV.

Classification and morphological parameters of the coracoid process in Chinese population

INTRODUCTION

The coracoid process is an important anatomical structure of the scapula, which can be used as a landmark in the diagnosis and treatment of scapula related diseases, such as acromioclavicular joint dislocation, anterior shoulder instability, and coracoid fractures. The aim of this study was to classify the coracoid process according to morphology and to measure the morphological parameters of the coracoid process.

MATERIALS AND METHODS

A total of 377 dry and intact scapulae were collected and classified in terms of the connection between the shape of coracoid process and common things in life. The anatomical morphology and the position related to acromion and glenoid socket of the coracoid process were measured in each type by three independent researchers with a digital caliper. The measurements were averaged and recorded.

RESULTS

Based on obvious morphological features, five specific types of the coracoid process were described: Type I, Vertical 8-shape; Type II, Long stick shape; Type III, Short stick shape; Type IV, Water drop shape, and Type V, Wedge shape. Type I (30%) and Type III (29%) were more prevalent in China. The tip width of the coracoid process of Type IV was the shortest and significantly different compared to the other types (p <.05), contrary to the longest in Type V. The tip thickness of the coracoid process of Type I was the shortest and significantly different from the other types (p <.05).

CONCLUSIONS

The coracoid process was classified into five types based on obvious morphological features. Knowing of morphological classification and anatomical parameters of different types of the coracoid process, to some extent, may be helpful to diagnose and treat the shoulder joint disease, such as acromioclavicular joint dislocation, anterior shoulder instability, and coracoid fractures, and to theoretically reduce postoperative complications.

Single tunnel technique versus coracoid sling technique for arthroscopic treatment of acute acromioclavicular joint dislocation

To evaluate and compare the efficacy of two techniques for the treatment of acute acromioclavicular joint dislocation, the charts of 60 patients diagnosed with acute Rockwood type IV and V acromioclavicular joint dislocation that undergone arthroscopic fixation procedure with single tunnel technique (N = 30, 30.7 ± 5.7 years old) or coracoid sling technique (N = 30, 30.1 ± 5.4 years old) fixation were retrospectively reviewed. The Visual Analog Scale pain score, Constant shoulder functionality score, Karlsson acromioclavicular joint score, the time of return to sports and activity, and plain radiographs of the affected shoulder at different time points of follow-up were recorded for a minimum of 2 years post-op. The majority of the patients recovered to their preoperative activity levels with few complications. The average postoperative acromioclavicular and coracoclavicular distances were significantly narrower than preoperative measurements in both groups without significant difference between the two groups at 2 years post-op (P < 0.05). The coracoid sling technique group had reduced operative time, shorter time of recovery of shoulder movements, higher Constant functionality scores and Karlsson acromioclavicular joint scores, and fewer complications than the single tunnel technique group at the last follow-up (P < 0.05). Therefore, coracoid sling technique achieved superior clinical outcomes with fewer complications compared to the traditional single tunnel technique in arthroscopic treatment of acute acromioclavicular joint dislocation.

Coracoid tunnels in open and arthroscopic treatment of acromioclavicular dislocation: an experimental cadaveric study

PURPOSE

Treatment of acromioclavicular joint (ACJ) dislocation is not encoded uniquely. Type I and II injuries are usually treated conservatively, while types IV, V and VI surgically. Controversy still exists over the treatment of type III injuries. In the operative approach, there is no agreement on the best surgical technique. Our purpose is to compare the mini-open and arthroscopic approach focusing on the evaluation of the anatomical precision of the coracoid drilling.

METHODS

This is a controlled laboratory study. Ten fresh-frozen cadaveric shoulders were randomly assigned to the two techniques in order to compare them. We performed essential surgical gestures to drill the tunnel using MINAR® System (mini-open) and Dog-Bone® (ARTHREX, arthroscopic). The anatomical specimens were then subjected to CT-scan investigation. We statistically evaluated the precision of these two techniques analyzing DICOM files using two parameters. Parameter 1 evaluates the tunnel entry area on the superior side of the coracoid. Parameter 2 describes the orientation of the tunnel.

RESULTS

There are no statistically significant differences (95% confidence level) between arthroscopic and mini-open approach about the precision in the location of the coracoid hole, regarding the entry area (p = 1.00) and the orientation (p = 0.196).

CONCLUSION

The evidences collected enable the orthopedic surgeon to choose equally between the two techniques in the treatment of AC joint dislocation toward precision.

Clinical and radiological outcomes of acute Rookwood type IIIB acromioclavicular joint dislocation: Mini-open tightrope technique versus hook plate

OBJECTIVE

Treatment of acute Rookwood type III AC joint dislocation is still controversially discussed. ISAKOS suggested to subdivide type III AC joint injuries into type IIIA (stable) and type IIIB (unstable). The aim of this study was to compare clinical and radiographic outcomes between hook plate fixation and mini-open tightrope for the treatment of acute Rookwood type IIIB acromioclavicular joint dislocation.

METHODS

We conducted a retrospective clinical study of 112 patients with acute Rookwood type IIIB acromioclavicular joint dislocation who were treated surgically using either mini-open TightRope or hook plate from 2013 to 2019. All patients were followed up for 12 months. Clinical outcomes were evaluated using Visual Analogue Scale (VAS) and the Constant-Murley Score (CMS). Radiological results were assessed with the coracoclavicular distance (CCD), the change in clavicular elevation (ΔCE) and horizontal translation.

RESULTS

The length of incision was significantly shorter in the mini-open TightRope group than that in hook plate group (6.62±0.60 vs. 2.58±0.43 p <0.001). Duration of surgery was significantly shorter in the mini-open TightRope group than that in hook plate group (30.12±6.65 vs. 53.33±12.03; p < 0.001). Total blood loss volume was significantly less in the mini-open TightRope group than in the hook plate group. (23.85±7.88 vs. 70.67±24.62, p < 0.001). VAS and CMS in mini-open TightRope group were better than that in hook plate group at 2 weeks after surgery (VAS: 2.19±0.92 vs. 3.30±1.51, p = 0.002 and CMS 69.80±5.61 vs. 57.53±9.24, p<0.001) and 3 month after surgery (VAS: 1.19±0.48 vs. 3.07±1.36, p<0.001 and CMS 89.30±4.47 vs. 83.20±12.11, p = 0.205). There was no statistically significant difference between two groups at 12 months follow-up including VAS, CMS, the CC distance,ΔCE and the degree of dynamic horizontal translation. There were 2 complications in the hook plate group including 1cut out and 1 superficial wound infection.

CONCLUSION

The mini-open tightrope has better function and relieves pain in the early postoperative period compared to hook plate, and at the last follow up two groups have similar clinical and radiological outcomes. Mini-open TightRope fixation is a good option for the treatment of acute Rockwood types ⅢB AC joint dislocation.

Anatomical versus non-anatomical configuration of double coraco-clavicular tunnel technique in acromioclavicular joint reconstruction

PURPOSE

Horizontal instability is a common problem after acromioclavicular joint injuries. The aim of this study was to evaluate if there is a difference regarding horizontal stability between an anatomical and a non-anatomical configuration of the double tunnel coraco-clavicular ligament reconstruction of the acromioclavicular joint.

METHODS

Thirteen acromioclavicular joints of human cadaveric shoulders in ethanol-glycerin fixation were included in the study and underwent cyclic anterior and posterior translational testing at a load of 70 N using an electromechanical uniaxial testing machine. The shoulders were randomly assigned to the following groups: double coraco-clavicular tunnel technique in an anatomical configuration (DCTa) and double coraco-clavicular tunnel technique in an inverse configuration of the anatomical position (DCTb). The dislocation was recorded with a 3D optical measuring system.

RESULTS

The total horizontal displacement (p₁₀ = 0.0221; p₅₀₀₀ = 0.082) was significantly higher for the non-anatomical reconstruction (DCTb) compared to the anatomical reconstruction (DCTa) after every measured amount of cycles. The increase in displacement for DCTb group was overall higher than the increase in displacement for DCTa group but without significance.

CONCLUSION

Reconstruction of the CC ligaments in an anatomical configuration with two suture devices results in a significantly higher stability of the AC joint in the horizontal plane than reconstruction of the CC ligaments in a non-anatomical configuration. Based on the results of this biomechanical in vitro study, the use of a double coraco-clavicular reconstruction should focus on an anatomically correct position of the suture devices.

[Arthroscopically-assisted treatment of acute and chronic dislocations of the acromioclavicular joint : A prospective clinical trial]

BACKGROUND

Injuries of the acromioclavicular joint (ACJ) are frequent and often occur during sports. While arthroscopically-assisted stabilization of acute injuries of the ACJ is a well-established procedure, there is not much data available for arthroscopically-assisted stabilization of chronic injuries of the ACJ.

OBJECTIVES

This study assesses clinical and radiological results of arthroscopically-assisted stabilization of acute and chronic injuries of the ACJ.

MATERIALS AND METHODS

Thirty-six patients with acute and chronic injuries of the ACJ were assessed in a prospective clinical trial. Twenty-five patients with acute injuries (group A) and eleven patients with chronic injuries (group B) were included in this study. Patients of group A were operated using two suture-button systems, while patients of group B received one suture-button system and an autologous gracilis tendon graft.

RESULTS

In group A, the mean preoperative Constant score rated 38, and the ASES score rated 34. At follow-up the Constant score (92) and the ASES score (89) had improved. Panorama views revealed an increased coracoclavicular distance of the affected shoulder (15.8 mm) in comparison to the contralateral shoulder (10.9 mm). In group B, the preoperative Constant score measured 57. It improved to 72 points at follow-up. The ASES score improved from 39 to 72 points in the same period. Panorama views revealed an increased coracoclavicular distance of the affected shoulder (18.9 mm) in comparison to the contralateral shoulder (12.4 mm).

CONCLUSIONS

Stabilization of acute injuries of the ACJ with two suture-button systems is related to very good shoulder function after one year. The native coracoclavicular distance cannot be restored with this procedure. Stabilization of chronic injuries of the ACJ with a suture-button system and an autologous gracilis tendon graft is related to improved shoulder function after one year. However, shoulder function cannot be fully restored with the stabilization technique presented.

Arthroscopic Coracoclavicular Ligament Stabilization Using Coracoid Cortical Suspension in Acute Acromioclavicular Joint Injury; Precision of Drill Tunnel

Acute acromioclavicular joint separation is a common injury of the shoulder. There are several methods for treating this condition; however, there is no gold standard established. Herein, we propose an arthroscopic method for the treatment of acute acromioclavicular joint separation using a simple cortical suspension device at the coracoid base via a transclavicular-transcoracoidal tunnel and tieing the suture at the clavicle. This method has the advantages of making a precision drilling tunnel using small implants and small stab incisions, with better cosmetic results and less implant irritation.

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.

Early clinical and radiographic results of fixation with the TightRope device for Rockwood type V acromioclavicular joint dislocation: A retrospective review of 15 patients

OBJECTIVE

The aims of this study were, first, to assess the loss of reduction after fixation of Rockwood type V acromioclavicular joint dislocation (ACJD) with the TightRope device (Arthrex, Naples, FL, USA) and, second, to present the functional and radiological outcomes of this treatment.

METHODS

We retrospectively reviewed the medical records of 15 patients (12 males; mean age=39.2 years; age range=23-61) with Rockwood type V ACJD who were treated by the TightRope fixation device. The mean follow-up period was 19.3 (range=12-30) months. Functional status was assessed using the Constant-Murley score (CMS) at the final follow-up examination. To determine the reduction loss of ACJ, we measured and compared the coracoclavicular (CC) distance using radiographs with Zanca view in the early postoperative period and at the final follow-up examination. The fixation procedures were performed with an open technique using the TightRope fixation device.

RESULTS

The mean CMS at the final follow-up was 93.2 (range=82-100) points. All the patients experienced full recovery of the shoulder's range of motion, were able to return to the activities of daily living, and were satisfied with the treatment. ACJ reduction was successfully achieved in all the patients using the TightRope technique. Postoperative radiographs revealed no reduction loss in the ACJ, and the CC distance was well maintained. The mean CC distance was 19.95 (range=13.1-28.3) mm before surgery. The mean CC distance was 7.47 (range=4.2-11.5) mm in the early postoperative radiographic measurements. This difference was statistically significant (p=0.001). The mean CC distance at the final follow-up examination was 7.70 (range=4.5-11.7) mm. At the final follow-up visit, the shoulders of all the patients were still completely reduced, with a mean difference in the CC of 0.23 (range=0-1.3) mm compared with that in the early postoperative period. The difference in the CC between the early postoperative and final follow-up intervals was not statistically significant (p=0.055). No patient experienced recurrence or required an operation for hardware removal.

CONCLUSION

It seems that the TightRope device can provide anatomical restoration in patients with acute type V ACJD without subluxation at the final follow-up examination.

LEVEL OF EVIDENCE

Level IV, Therapeutic study.

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.

Novel Double Endobutton Technique Combined with Three-Dimensional Printing: A Biomechanical Study of Reconstruction in Acromioclavicular Joint Dislocation

Objective

To reconstruct the acromioclavicular (AC) joint using an adjusted closed‐loop double Endobutton technique via a guiding locator that was applied using three‐dimensional (3D) printing technology. At the same time, the reliability and safety of the novel double Endobutton (NDE) were tested by comparing the biomechanics of this technique with the TightRope (TR) approach.

Methods

This retrospective study was conducted between January 2017 and January 2019. The Department of Anatomy at Southern Medical University obtained 18 fresh‐frozen specimens (8 left and 10 right; 12 men and 6 women). First, the guiding locators were applied using 3D printing technology. After preparation of materials, specimens were divided into an NDE group, a TR group, and a normal group. In the NDE and TR groups, the navigation module was used to locate and establish the bone tunnels; after that, the NDE or TR was implanted. However, the Endobuttons were fixed while pressing the distal clavicle downwards and the length of the loop could be adjusted by changing the upper Endobutton in the NDE group while the suture button construct was tensioned and knotted after pressing down the distal clavicle in the TR. Finally, load testing in anterior–posterior (AP), superior–inferior (SI), and medial–lateral (ML) directions as well as load‐to‐failure testing in the SI direction were undertaken to verify whether the NDE or TR had better biomechanics.

Results

In the load testing, the displacements of the NDE and TR groups in the AP, SI, and ML direction were significantly shorter than those of the normal group (P < 0.05). In the load‐to‐failure testing, the ultimate load of the NDE and TR groups had significantly higher increases than the normal group (722.16 ± 92.04 vs 564.63 ± 63.05, P < 0.05; 680.20 ± 110.29 vs 564.63 ± 63.05, P < 0.05). However, there was no statistically significant difference between the two techniques for these two tests (P > 0.05). In the NDE group, four of six failures were a result of tunnel fractures of the coracoid, while two of six were due to suture breakage. In the TR, three failures were due to coracoid tunnel fractures, one was a result of a clavicle tunnel fracture, and the rest were due to suture breakage. In the normal group, half of the failures were a result of avulsion fractures of the conical ligament at the point of the coracoid process, and the other three were due to rupture of the conical ligament, fracture of the distal clavicle, and fracture of the scapular body.

Conclusion

As for the TR technique, the stability and strength of the AC joint were better in patients who underwent reconstruction using the NDE technique than in the intact state.

Suture Button Versus Hook Plate for Acute Unstable Acromioclavicular Joint Dislocation: A Meta-analysis

BACKGROUND

Surgical treatment is indicated for unstable acromioclavicular (AC) joint dislocation. The hook plate (HP) technique is a commonly used treatment method, but the use of the suture button (SB) technique is increasing.

PURPOSE

To conduct a meta-analysis of clinical studies evaluating patient outcomes between the SB and HP techniques for acute unstable AC joint dislocation.

STUDY DESIGN

Meta-analysis.

METHODS

A literature search of the Embase, PubMed, and Cochrane Library databases was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Cohort studies and case-control studies comparing the SB and HP procedures for acute unstable AC joint dislocation were included. Statistical analysis was performed with RevMan (v 5.3.5).

RESULTS

Eight clinical studies that met the inclusion criteria were identified and included a total of 204 patients treated with the SB technique and 195 patients with the HP technique. Patients treated with the SB technique had a higher Constant score (mean difference [MD], 3.95; 95% CI, 1.20-6.70; P = .005) and a lower visual analog scale pain score (MD, -0.75; 95% CI, -1.12 to 0.37; P < .0001) when compared with the HP technique. No significant differences in operation time (MD, -0.38; 95% CI, -7.14 to 6.37; P = .91), coracoclavicular distance (MD, -0.07; 95% CI, -0.49 to 0.35; P = .75), complications (odds ratio, 0.59; 95% CI, 0.22-1.54; P = .28), and loss of reduction (odds ratio, 2.55; 95% CI, 0.66-9.83; P = .17) were found between the SB and HP techniques. The subgroup analysis showed that the arthroscopic SB technique resulted in a higher Constant score (MD, 6.75; 95% CI, 4.21-9.29; P < .00001) as compared with the HP technique, but no differences were observed between the open SB and HP techniques (MD, 0.69; 95% CI, -0.82 to 2.20; P = .37).

CONCLUSION

This meta-analysis demonstrated that the SB technique resulted in better functional outcomes and a reduced visual analog scale pain score when compared with the HP technique. However, for operation time, coracoclavicular distance, complications, and loss of reduction, there were no statistically significant differences between the techniques. Compared with the open procedure, arthroscopic SB may be superior for better functional outcomes.

Morphometric analysis of the coracoid process and glenoid width: a 3D-CT study

Background

Data regarding the parameters of the coracoid process and glenoid width are insufficient, and information on gender, age, and ethnic differences in the parameters appear lacking in the Chinese population. This study aimed to investigate the morphometric parameters in the coracoid process and glenoid width.

Methods

Using our institution’s electronic database, we selected 84 patients (55 males and 29 females) who underwent a shoulder computed tomography (CT) scan from January 2017 to May 2018 in this study. Mimics19.0 software was used for three-dimensional (3D) reconstruction of CT and to measure the morphometric parameters of the coracoid process and glenoid width. Subgroup analyses stratified by gender and age were conducted and the parameters were compared with previously published reports. All data were statistically analysed by SPSS23.0 Statistical Package.

Results

A positive and significant relationship between the coracoid process and the glenoid width (R > 0.758, P < 0.01) was found. The midpoint width represents 52% (41–62%) of the glenoid width; the midpoint height, 40% (31–53%) of the glenoid width. Significant differences in all parameters between males and females were noted (P < 0.05). No significant differences among the age groups were observed (P > 0.05), whereas significant differences in almost all parameters between the ethnic groups were observed (P < 0.05).

Conclusion

Our results could supplement the information in the shoulder joint database with morphometric parameters and provide a reference for theoretical research on coracoid osteotomy, which may in turn help surgeons in the evaluation of coracoid process transfer.

Current Concepts in the Operative Management of Acromioclavicular Dislocations: A Systematic Review and Meta-analysis of Operative Techniques

BACKGROUND

Acromioclavicular (AC) instability is a frequent injury affecting young and athletic populations. Symptomatic, high-grade dislocations may be managed by a myriad of operative techniques that utilize different grafts to achieve reduction. Comparative data are lacking on the ability of these techniques to achieve excellent patient outcomes and stable AC reduction and to minimize complications.

PURPOSE

To systematically review the outcomes and complications of different techniques of AC joint reconstruction.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

The MEDLINE, Scopus, Embase, and Cochrane Library databases were accessed to perform a systematic review of the scientific literature from 2000 to 2018 using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria with the following keywords: "acromioclavicular" and "reconstruction." Included articles were evaluated for loss of reduction, complication rate, revision rate, and change in coracoclavicular distance. Articles were stratified by graft and surgical material used: suture only, Endobutton with suture, TightRope, GraftRope, synthetic artificial ligament, tendon graft, and Weaver-Dunn coracoacromial ligament transfer. These outcomes were pooled using a random-effects model and stratified by surgical technique and arthroscopic versus open reconstruction.

RESULTS

Fifty-eight articles were included in the analysis, with 63 homogeneous populations composed of 1704 patients. The mean age was 37.1 years (range, 15-80 years) with a mean follow-up of 34.3 months (range, 1.5-186 months). The overall failure rate was 20.8% (95% CI, 16.9%-25.2%). The overall pooled complication rate was 14.2% (95% CI, 10.5%-18.8%). The most common complications were infection (6.3% [95% CI, 4.7%-8.2%]), fracture to the coracoid or distal clavicle (5.7% [95% CI, 4.3%-7.6%]), and hardware/button failure (4.2% [95% CI, 3.1%-5.8%]). There were no differences between arthroscopic and open techniques in regard to loss of reduction (P = .858), overall complication rate (P = .774), and revision rate (P = .390). Open surgery had a greater rate of clavicular/coracoid fractures than arthroscopic surgery (P = .048). Heterogeneity, best assessed from the pooled loss of reduction, was measured as I² = 64.0%.

CONCLUSION

Open and arthroscopic AC joint reconstruction techniques have no differences in loss of reduction, the complication rate, and the revision rate based on the available literature. Complications are significant, and profiles vary between surgical techniques, which should be evaluated in the decision making of selecting the technique.

Arthroscopy-assisted fixation of fracture of the distal part of the clavicle by subcoracoid suture and clavicle button

INTRODUCTION

Neer IIB displaced fracture of the distal part of the clavicle is often treated surgically. Arthroscopy-assisted surgery was recently developed. The aim of the present study was to present an original technique of subcoracoid suture under arthroscopy, with clinical and radiological results.

HYPOTHESIS

Arthroscopy-assisted subcoracoid suture in Neer IIB clavicle fracture provides satisfactory results.

MATERIAL AND METHODS

Fourteen patients, with a mean age of 34.6 years (range, 24-51 years) with Neer IIB displaced clavicle fracture treated by subcoracoid suture between January 2013 and January 2017 were included. Clinical assessment comprised demographic data, weighted Constant score and Subjective Shoulder Value (SSV). Radiologic assessment comprised AP shoulder view.

RESULTS

Bone healing was systematic within 3 months, except in 1 case of delayed healing. Mean follow-up was 20 months (range, 6-55 months). At last follow-up, mean weighted Constant score was 91% (range, 85-95%) and mean SSV 95% (range, 85-100%). 4 patients reported clavicle button irritation, 2 of whom asked for hardware removal.

DISCUSSION

Arthroscopy-assisted subcoracoid suture provided satisfactory clinical results. There were no cases of implant failure, probably because the technique caused no iatrogenic coracoid trauma. Clavicle button irritation sometimes required hardware removal.

LEVEL OF EVIDENCE

IV.

Anatomic Tunnel Placement Is Not Feasible by Transclavicular-Transcoracoid Drilling Technique for Coracoclavicular Reconstruction: A Cadaveric Study

PURPOSE

To evaluate the feasibility of anatomic tunnel placement by a transclavicular-transcoracoid drilling technique and with reference to the coracoclavicular ligaments' insertional anatomy and their orientations.

METHODS

We used 12 fresh-frozen human cadaveric shoulders (6 matched pairs; mean age, 70 years; age range, 51-82 years) to simulate intraoperative tunnel placement with the transclavicular-transcoracoid drilling technique. After both the conoid and trapezoid ligaments were identified, two 2.5-mm guide pins were inserted from the clavicle to the coracoid, passing the centers of the clavicular and coracoid insertions of the conoid and the trapezoid ligaments, in a collinear fashion to the orientation of both ligaments. The entry point of the drill at the clavicle and the exit point at the coracoid undersurface, as well as the tunnel orientations, were measured. Complications due to the procedure, including a breach of the bone cortex of the clavicle and/or coracoid process, were recorded.

RESULTS

The transclavicular-transcoracoid drilling technique for anatomic conoid ligament tunnel placement resulted in a medial cortical breach at the coracoid process in 6 of 12 shoulders. In the remaining 6 shoulders without a breach, the distance of the exit point from the medial cortex of the inferior coracoid process was only 3.6 ± 4.3 mm. For anatomic trapezoid ligament tunnel placement, no medial cortex breaching at the coracoid process occurred. However, the distance of the exit point was 3.1 ± 4.2 mm, indicating an eccentric location to the medial cortex of the coracoid process, similar to the conoid ligament.

CONCLUSIONS

This cadaveric study showed that anatomic tunnel placement by the transclavicular-transcoracoid drilling technique would not be feasible without breaching or almost breaching the medial cortex of the coracoid process.

CLINICAL RELEVANCE

The transclavicular-transcoracoid drilling technique for CC ligament reconstruction may not reproduce the anatomy of the CC ligaments but may place the coracoid process at high risk of fracture during tunnel placement.

Modified closed-loop double-endobutton technique for repair of rockwood type III acromioclavicular dislocation

Acromioclavicular dislocation (ACD) is a common injury. According to the Rockwood classification, ACD is classified into six types (type I–VI); however, for type III injuries, it remains controversial whether or not operative treatment should be applied. Numerous studies have advocated early surgical treatment to ensure early rehabilitation activities. Thus, the present study aimed to investigate a modified closed-loop double-endobutton technique (MCDT), that may be used to repair Rockwood type III ACD. In the current study, 61 patients with Rockwood type III ACD were enrolled during a period of 5 years at the Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University. Patients were divided into three groups according to the surgical method used, the MCDT group (n=20), the common closed-loop double-endobutton technique (CCDT) group (n=21), and the clavicular hook plate fixation (CHPF) group (n=20). Preoperative and intraoperative information were recorded. Furthermore, the functional scores of injured shoulder were evaluated prior to surgery and following surgery with a 1-year follow-up. Among the three groups, postoperative functional scores were significantly more improved compared with those prior to surgery (P<0.05), and no significant difference was observed regarding the coracoclavicular interval with the 1-year follow-up (P>0.05). Postoperative functional scores in the MCDT and CCDT groups were significantly more improved compared those in the CHPF group (P<0.05). In addition, the duration of surgery in the MCDT group was significantly shorter compared with that in the CCDT group (P<0.05). Furthermore, compared with the CHPF group, the incision length was significantly shorter with reduced hemorrhage in the MCDT group (P<0.05). In conclusion, the results of the current study suggest that MCDT is more simple, convenient and efficient compared with CCDT, and is worth popularizing.

Study on the anatomic relationship between the clavicle and the coracoid process using computed tomography scans of the shoulder

BACKGROUND

The current trend in the treatment of acromioclavicular dislocations is to reconstruct the coracoclavicular ligaments by using transosseous tunnels in the coracoid process or in the clavicle, yet there is no definition as to the location of these. To study the anatomic relationship between the coracoid process and the clavicle, we made measurements to find a convergence point (cP) between them that has intraoperative applicability for creating transosseous tunnels.

METHODS

We analyzed 74 computed tomography scans (40 female and 34 male patients). Measurements were taken in the axial and sagittal planes and obtained from a cP, as determined by the intersection of the cortical surface of the clavicle and the coracoid process, with various relationships having been established.

RESULTS

On average, the cP was determined to be about 2.9 cm and 2.5 cm distant from the coracoid process apex for male and female patients, respectively, whereas the width at this position was determined to be 2.1 cm and 1.9 cm. In the clavicle, this point is on average 2.9 cm and 2.5 cm distant from the acromioclavicular joint in male and female patients, respectively, and its anteroposterior width at this point is on average 1.9 cm and 1.6 cm.

CONCLUSION

The cP of the clavicle and the coracoid process was determined with the aim of preparing bone tunnels in operations for treating acromioclavicular dislocations.

Anatomic Coracoclavicular Ligament Reconstruction for the Treatment of Acute Acromioclavicular Joint Dislocation: Minimum 10-Year Follow-up

Background:

The long-term clinical and radiographic outcomes following coracoclavicular (CC) ligament reconstruction for the operative treatment of acute acromioclavicular (AC) joint dislocation remain uncertain. The purpose of the present study was to determine the long-term clinical and radiographic outcomes of CC ligament reconstruction and to identify risk factors for unfavorable outcomes.

Methods:

We reviewed 20 cases of AC joint dislocation in 19 patients (18 male and 1 female; mean age, 32.3 years) that were treated with single-bundle reconstruction. The mean duration of follow-up was 12.7 years. We measured the CC vertical distance (CCD) on the anteroposterior view and compared the affected and unaffected sides (CCD ratio). We divided the patients into those with a CCD ratio of <25% (Group 1) and those with a CCD ratio of ≥25% (Group 2). We radiographically investigated the clavicular tunnel anteroposterior (CTAP) angle, clavicular tunnel ratio, and coracoid tunnel orientation on the basis of the entry and exit points at the base of the coracoid. For the coracoid tunnel orientation, we compared center-center orientation and noncenter-center orientation.

Results:

Group 1 comprised 17 cases (85%), and Group 2 comprised 3 cases (15%). At the time of the latest follow-up, Group 1 had a significantly higher mean Constant score than Group 2 (98.2 compared with 90.7; p = 0.038). Of the 3 radiographic parameters, only the CTAP angle was significantly different between the 2 groups (p < 0.0001). Two (67%) of the 3 cases in Group 2 were associated with posterior AC joint displacement.

Conclusions:

CC ligament reconstruction for the treatment of acute AC joint dislocation resulted in successful long-term clinical and radiographic outcomes. It is important to decrease the CTAP angle and to ensure proper anatomic placement of the clavicular and coracoid tunnels at the time of surgery.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Coracoid Process Morphology using 3D-CT Imaging in a Malaysian Population

Introduction: The aims of this study are to define the coracoid process anatomy in a Malaysian population, carried out on patients in Hospital Serdang with specific emphasis on the dimension of the base of coracoid process which is important in coraco-acromial (CC) ligament reconstruction, to define the average amount of bone available for use in coracoid transfer, and to compare the size of coracoid process based on gender and race, and with findings in previous studies.

Materials and Methods: Fifteen pairs of computed tomography (CT) based 3-dimensional models of shoulders of patients aged between 20 to 60 years old were examined. The mean dimensions of coracoid were measured and compared with regards to gender and race. The data were also compared to previously published studies.

Results: The mean length of the coracoid process was 37.94 ± 4.30 mm. Male subjects were found to have larger-sized coracoids in all dimensions as compared to female subjects. The mean tip of coracoid dimension overall was 19.99 + 1.93mm length × 10.03 + 1.48mm height × 11.63 + 2.12mm width. The mean base of coracoid dimension was 18.96 + 3.71mm length × 13.84 + 1.76mm width. No significant differences were observed with regards to racial denomination. The overall coracoid size measurements were found to be smaller compared to previous studies done on the Western population.

Conclusion: This study may suggest that Malaysians have smaller coracoid dimension compared to Caucasians. The findings further suggest that the incidence of coracoid fracture and implants pull out in Malaysian subjects may be higher.

Anatomic Variation in Morphometry of Human Coracoid Process among Asian Population

Ethnic origin plays an important role in bone morphometry. Studies examining the influence of coracoid process have focused primarily on adults and have not included people from diverse Asian ethnic backgrounds. Our goal was to explore ethnic differences in morphometry of coracoid among Asian population. We performed morphometric measurements of coracoid process on cadaveric shoulders and shoulder CT scans from 118 specimens. The cadaveric sample included Indian (46%), Chinese (27%), and Myanmarese (27%) subjects, while the CT scans sample included Chinese (67%) and Malay (33%) subjects. The morphometric measurements were performed using digital caliper and software developed at Golden Horses Health Sanctuary (GHHS). In the Indian cadaveric shoulders, the coracoid process is better developed than the other groups with the exception of the tip width of coracoid process. There are significant differences in almost all measurements (P < 0.05) between the ethnic groups. On the other hand, the morphometry of coracoid process from CT scans data is bigger in Chinese than Malay subjects when stratified by sex (P < 0.05). Moreover, in all morphometric measurements, the females had smaller measurements than males (P < 0.05). Understanding such differences is important in anatomy, forensic and biological identity, and orthopaedic and shoulder surgeries.

[Injuries of the acromioclavicular joint: Hook plate versus arthroscopy]

Acute acromioclavicular (AC) joint injuries are common in clinical practice. The hook plate is a well-established conventional operative treatment option for high grade instability; however, arthroscopically-assisted flexible double button techniques are increasingly being used. Both procedures lead to good or excellent results. The advantages of the hook plate are the simple surgical technique and the possibility of an early functional aftercare. The minimally invasive one-step procedure with the possibility of identification and treatment of frequently concomitant glenohumeral pathologies is advantageous for the arthroscopic technique but mobilization is more restrictive. Available comparative studies have shown no significant clinical differences but a tendency towards better results with a higher degree of acceptance among patients for the arthroscopic and minimally invasive non-rigid double button procedures.

[Arthroscopically assisted techniques for treatment of acute and chronic acromioclavicular joint injuries]

Acute and chronic acromioclavicular (AC) joint dislocation is frequently encountered in the routine clinical practice. This injury can lead to significant impairment of shoulder girdle function. Therapy based on the severity of injury is recommended to re-establish correct shoulder function. The static radiographic Rockwood classification is used to define the degree of dislocation but the clinical aspects and functional x-ray imaging of horizontal AC joint instability should also be considered for selection of the appropriate procedure. Rockwood grades I and II injuries are treated non-operatively with early functional exercise. The approach for Rockwood grade III injuries should be individual and patient-specific, with non-surgical procedures for low functional requirement patients with a high risk for surgical interventions. For patients with high demands on shoulder function surgery is recommended. A detailed diagnostic assessment frequently reveals Rockwood grade III injuries to be type IV injuries. Rockwood types IV and V AC joint dislocations require surgery for sustained stability. Treatment of acute injuries is recommended within 1-3 weeks after trauma but there is no clear evidence of a cut-off for the presence of chronic injuries. Various surgical techniques have been described in the literature. This article presents an arthroscopically assisted technique that addresses both vertical and horizontal instability of the AC joint.

Shoulder acromioclavicular joint reconstruction options and outcomes

Acromioclavicular joint separations are a common cause of shoulder pain in the young athletic population. In high-grade injuries, acromioclavicular joint reconstruction procedures may be indicated for functional improvement. There is currently no gold standard for the surgical management of these injuries. Multiple reconstructive options exist, including coracoclavicular screws, hook plates, endobutton coracoclavicular fixations, and anatomic ligament reconstructions with tendon grafts. This article aims to review pertinent acromioclavicular joint anatomy and biomechanics, radiographic evaluation, classification system, as well as reconstruction options, outcomes, and complications.

PREFERED SURGICAL TECHNIQUE USED BY ORTHOPEDISTS IN ACUTE ACROMIOCLAVICULAR DISLOCATION

Objective:

To determine whether training on shoulder and elbow surgery influences the orthopedist surgeons' preferred technique to address acute acromioclavicular joint dislocation (ACD).

Methods:

A survey was conducted with shoulder and elbow specialists and general orthopedists on their preferred technique to address acute ACD.

Results:

Thirty specialists and forty-five general orthopedists joined the study. Most specialists preferred the endobutton technique, while most general orthopedists preferred the modified Phemister procedure for coracoclavicular ligament repair using anchors. We found no difference between specialists and general orthopedists in the number of tunnels used to repair the coracoclavicular ligament; preferred method for wire insertion through the clavicular tunnels; buried versus unburied Kirschner wire insertion for acromioclavicular temporary fixation; and time for its removal; and regarding the suture thread used for deltotrapezoidal fascia closure.

Conclusion:

Training on shoulder and elbow surgery influences the surgeons' preferred technique to address acute ACD. Level of Evidence V, Expert Opinion.

Radiographic failure and rates of re-operation after acromioclavicular joint reconstruction: a comparison of surgical techniques

AIMS

To compare radiographic failure and re-operation rates of anatomical coracoclavicular (CC) ligament reconstructional techniques with non-anatomical techniques after chronic high grade acromioclavicular (AC) joint injuries.

PATIENTS AND METHODS

We reviewed chronic AC joint reconstructions within a region-wide healthcare system to identify surgical technique, complications, radiographic failure and re-operations. Procedures fell into four categories: (1) modified Weaver-Dunn, (2) allograft fixed through coracoid and clavicular tunnels, (3) allograft loop coracoclavicular fixation, and (4) combined allograft loop and synthetic cortical button fixation. Among 167 patients (mean age 38.1 years, (standard deviation (sd) 14.7) treated at least a four week interval after injury, 154 had post-operative radiographs available for analysis.

RESULTS

Radiographic failure occurred in 33/154 cases (21.4%), with the lowest rate in Technique 4 (2/42 4.8%, p = 0.001). Half the failures occurred by six weeks, and the Kaplan-Meier survivorship at 24 months was 94.4% (95% confidence interval (CI) 79.6 to 98.6) for Technique 4 and 69.9% (95% CI 59.4 to 78.3) for the other techniques when combined. In multivariable survival analysis, Technique 4 had better survival than other techniques (Hazard Ratio 0.162, 95% CI 0.039 to 0.068, p = 0.013). Among 155 patients with a minimum of six months post-operative insurance coverage, re-operation occurred in 9.7% (15 patients). However, in multivariable logistic regression, Technique 4 did not reach a statistically significant lower risk for re-operation (odds ratio 0.254, 95% CI 0.05 to 1.3, p = 0.11).

CONCLUSION

In this retrospective series, anatomical CC ligament reconstruction using combined synthetic cortical button and allograft loop fixation had the lowest rate of radiographic failure.

TAKE HOME MESSAGE

Anatomical coracoclavicular ligament reconstruction using combined synthetic cortical button and allograft loop fixation had the lowest rate of radiographic failure.

Prognosis Driven Rehabilitation After Rotator Cuff Repair Surgery

Background:

Rehabilitation after rotator cuff repair surgery has been the focus of several clinical trials in the past decade. Many illuminate new evidence with regard to the prognosis of structural and functional success after surgery.

Methods:

A selective literature search was performed and personal physiotherapeutic and surgical experiences are reported.

Results:

Post-operative rehabilitation parameters, namely the decision to delay or allow early range of motion after surgery, play a large role in the overall success after surgery. Using a prognosis driven rehabilitation program offers clinicians a means of prescribing optimal rehabilitation parameters while ensuring structural and functional success. This commentary aims to synthesize the evidence in a spectrum of prognostic factors to guide post-operative rehabilitation.

Conclusion:

The optimal rehabilitation program after rotator cuff repair surgery is debatable; therefore, we suggest using a spectrum of prognostic factors to determine a rehabilitation program suited to ensure structural and functional success, quickly and safely.

Effect of Coracoid Drilling for Acromioclavicular Joint Reconstruction Techniques on Coracoid Fracture Risk: A Biomechanical Study

PURPOSE

To biomechanically compare the stability of the coracoid process after an anatomic double-tunnel technique using two 4-mm drill holes or a single-tunnel technique using one 4-mm or one 2.4-mm drill hole.

METHODS

For biomechanical testing, 18 fresh-frozen cadaveric scapulae were used and randomly assigned to one of the following groups: two 4-mm drill holes (group 1), one 4-mm drill hole (group 2), or one 2.4-mm drill hole (group 3). After standardized coracoid drilling, load was applied to the conjoined tendons at a rate of 120 mm/min and ultimate failure load, along with the failure mode, was recorded.

RESULTS

There was no significant difference between groups regarding load to failure. Mean load to failure in group 1 was 392 N; group 2, 459 N; and group 3, 506 N. The corresponding P values were .55, .74, and .20 for group 1 versus group 2, group 2 versus group 3, and group 1 versus group 3, respectively. However, the failure mode for the group with one 4-mm drill hole and the group with two 4-mm drill holes was coracoid fracture, whereas the group with one 2.4-mm drill hole showed 5 tears of the conjoined tendons and only 1 coracoid fracture (P = .015).

CONCLUSIONS

Although there was no significant difference regarding load-to-failure testing between groups, the failure mechanism analysis showed that one 2.4-mm drill hole led to less destabilization of the coracoid than one or two 4-mm drill holes.

CLINICAL RELEVANCE

Techniques with small, 2.4-mm drill holes might decrease the risk of severe iatrogenic fracture complications.

Surgical treatment of acute acromioclavicular joint dislocations: hook plate versus minimally invasive reconstruction

PURPOSE

This study was performed to compare the clinical results of a minimally invasive technique for acute acromioclavicular (AC) joint dislocation repair with the traditional hook plate fixation.

METHODS

Forty-four patients with an acute (within 2 weeks after trauma) complete AC joint separation (35 male, nine female; median age 36.2 years, range 18-56) underwent surgical repair with either a minimally invasive AC joint repair or a conventional hook plate. Functional outcome was evaluated using the Constant-Murley Score (CMS), the TAFT score and the AC joint instability score (ACJI). Radiographic evaluation was performed with bilateral anterior-posterior (a.p.) stress and Alexander views.

RESULTS

All patients were available after a median follow-up of 32 months (range 24-51). There were no significant differences in the mean CMS, Taft score and the ACJI between the two groups. The radiological assessment revealed no significant difference in the coracoclavicular distance. In both groups, a slight loss of reduction was observed. Periarticular ossification was seen in 11 patients of the minimally invasive AC joint repair and eight patients of the hook plate group but this did not affect the final outcome. Hook plates were removed after a median interval of 11.9 weeks (range 10-13).

CONCLUSION

Good clinical results can be achieved with both minimally invasive AC joint repair and hook plate fixation. However, in the hook plate group a second operation is mandatory for plate removal.

LEVEL OF EVIDENCE

III.

Arthroscopic Reconstruction of the Coracoclavicular Ligaments Using a Coracoid Cerclage Technique

This technical note discusses the arthroscopic coracoid cerclage technique for double-bundle coracoclavicular ligament reconstruction in patients with nonacute symptomatic high-grade acromioclavicular separation injuries. This technique allows for an anatomic graft reconstruction of the coracoclavicular ligaments through an arthroscopic approach without the requirement to drill into the coracoid process. Early results are promising with high patient satisfaction and excellent reported clinical and radiographic outcomes. We believe this technique to be an anatomic, less invasive alternative to a complex shoulder procedure while sparing the structural integrity of the coracoid process and also allowing the surgeon to convert easily to a more traditional open surgical technique as necessary.

Arthroscopically guided navigation for repair of acromioclavicular joint dislocations: a safe technique with reduced intraoperative radiation exposure

Background

Accuracy evaluation of navigated image free placement of double cortical fixation buttons for coracoclavicular tunnel position in comparison to conventional drill guide based placement.

Methods

Twenty-six patients with acute acromioclavicular joint instability were included in this non-randomized cohort study. All patients were treated with a Double- TightRope technique. In 13 cases the conventional drill guide based placement was used (group 1). In 13 patients surgery was performed as a navigated procedure with a fluoro-free optoelectronic system (group 2). The number of coracoclavicular drillings per patient (First pass accuracy; FPA (%)) was documented, the subcoracoidal position of the fixation buttons has been evaluated and graded as “intended position achieved (IPA)” or “intended position not achieved (IPnA)”.

Results

In group 1 drilling had to be repeated in four patients (30.8 %) to achieve proper placement of the subcoracoidal fixation buttons. 100 % first pass accuracy was observed in group 2 (p = 0.03). In group 1, the intended position of the subcoracoid buttons was not achieved (IPnA) in six patients (46.2 %). In group 2 all intended positions were achieved (p = 0.005).

Conclusion

Arthroscopic controlled fluoro-free navigated coracoclavicular drilling for the repair of acromioclavicular joint dislocation has higher first pass accuracy in comparison to conventional drill guide based placement. Therefore the navigation enables a precise position of the drill holes, may reduce the risk of an iatrogenic coracoid fracture and migration of fixation devices.

Trial registration

Local institutional review board No. 061-14-10032014

Outcome After Arthroscopic Reconstruction of the Coracoclavicular Ligaments Using a Double-Bundle Coracoid Cerclage Technique

PURPOSE

We report the outcome of an arthroscopic technique for coracoclavicular ligament reconstruction using an anatomic coracoid cerclage.

METHODS

Between March 2011 and September 2012, 12 consecutive patients with symptomatic chronic (>4 weeks from injury) type V acromioclavicular separation for which nonoperative treatment failed were treated with arthroscopic double-bundle reconstruction of the coracoclavicular ligaments using tendon allograft by the first author. The clinical records, operative reports, and preoperative and follow-up radiographs were reviewed. The visual analog scale score, Subjective Shoulder Value, Simple Shoulder Test score, and Constant-Murley score were evaluated preoperatively and at each follow-up appointment.

RESULTS

The study included 12 shoulders in 12 young active-duty soldiers with symptomatic high-grade acromioclavicular separation who were treated with a technique for arthroscopic reconstruction of the coracoclavicular ligaments. The mean age was 25 years (range, 20 to 35 years). The injury occurred during sports activity in 11 patients. One patient was injured in a motorcycle accident. The mean time from injury to surgery was 17.8 months (range, 1.5 to 72 months). The minimum length of follow-up was 24 months (mean, 30.4 months; range, 24 to 42 months). The mean preoperative and postoperative outcome scores were significantly different (P < .0001) for all subjective outcome measures. The mean Constant-Murley score improved from 58.4 (range, 51 to 76) to 96 (range, 88 to 100). The mean visual analog scale score improved from 8.1 (range, 7 to 10) to 0.58 (range, 0 to 2). The mean Subjective Shoulder Value improved from 32.9% (range, 10% to 70%) to 95% (range, 80% to 100%). The mean Simple Shoulder Test score improved from 6 (range, 5 to 8) to 11.83 (range, 11 to 12). All patients returned to their normal preinjury level of activity by 6 months. Radiographs at last follow-up showed no loss of reduction with maintenance of the coracoclavicular interval. There was 1 complication (8.5%), a postoperative superficial wound infection, that was treated accordingly.

CONCLUSIONS

We present an arthroscopic technique for double-bundle tendon graft reconstruction of the coracoclavicular ligaments using the coracoid cerclage technique. This method showed good outcomes and maintenance of radiographic reduction with high patient satisfaction and a low complication rate.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

[New horizons for minimally invasive treatment of acromioklavikular joint injuries]

BACKGROUND

A novel radiation-free electromagnetic navigation system (ENS) method was developed and the feasibility and accuracy for transklavikular-transkorakoid drilling procedures were evaluated in an experimental setting.

METHODS

In this study ten arthroscopically assisted, electromagnetically navigated transkorakoid-transklavikular drilling procedures with subsequent implantation of two TightRope® (Arthrex, Naples, FL.) devices (anatomical reconstruction) were performed on five human cadavers. Postoperative computed tomography (CT) scan analysis was carried out to determine tunnel placement accuracy. All procedures were performed without fluoroscopy.

RESULTS

The mean overall operation time was 28.5 ± 6.6 min. Successful anatomical tunnel placement was achieved in 98.8 %. During the navigated drilling procedure no misguidance of the drill requiring directional readjustments or restarts occurred. No cortical breaches, fractures or complications occurred.

CONCLUSION

The electromagnetically navigated transkorakoid-transklavikular drilling procedure used in this study demonstrated high targeting accuracy, required no intraoperative x-ray radiation and was associated with no complications.

Image-free navigated coracoclavicular drilling for the repair of acromioclavicular joint dislocation: a cadaver study

BACKGROUND

Reconstruction of the coracoclavicular ligament functions to restore anatomic alignment of the clavicle and may improve biomechanical function and clinical outcomes. Improper placement of the coracoclavicular tunnel may inherently weaken the coracoid. The purpose of this study was to evaluate the feasibility and accuracy of navigated image-free placement of K-wires for coracoclavicular tunnel position in comparison to conventional drill guide-based placement.

MATERIALS AND METHODS

Eight human shoulder specimens were assigned for conventional technique with a coracoclavicular guide device (group CP) and the paired contralateral side for the navigated procedure (group NP) with an optoelectronic system with a fluoro-free software module. First-pass accuracy (%) and the K-wire trajectory (lateral-center orientation (LC), center-center (CC) orientation and medial-center orientation (MC) were measured.

RESULTS

In all navigated K-wires a 100 % first-pass accuracy was observed. In three of the eight (37.5 %) specimens of the drill guide-based group, drilling had to be repeated. One of them had to be repeated twice, resulting in eight versus twelve drillings for the navigated versus conventional group, respectively (p = 0.021). K-wire trajectory showed an MC orientation in most of the specimen (n = 9, group NP 4, group CP 5).

CONCLUSIONS

Image-free navigated coracoclavicular drilling for the repair of acromioclavicular joint dislocation has higher first-pass accuracy in comparison to conventional drill guide-based placement and, therefore, may enable a precise anatomic position of the drill holes and reduce the risk of an iatrogenic coracoid fracture.

Biomechanical evaluation of coracoid tunnel size and location for coracoclavicular ligament reconstruction

PURPOSE

The purpose of this study was to determine the effect of coracoid tunnel size and location on the biomechanical characteristics of cortical button fixation for coracoclavicular ligament reconstruction.

METHODS

Thirteen matched pairs of cadaveric scapulae were used to determine the effects of coracoid tunnel size, and 6 matched pairs were used to determine the effects of coracoid tunnel location. For tunnel size, a 4.5-mm hole was drilled in the base of the coracoid of one scapula and a 6-mm hole was drilled in the contralateral scapula. For tunnel location, 2 holes were drilled: (1) The first group received a hole centered in the coracoid base and a hole 1.5 cm distal from the first, along the axis of the coracoid. (2) The second group received holes that were offset anteromedially from the first set of holes (base eccentric and distal eccentric). A cortical button-suture tape construct was placed through each tunnel, and constructs were then loaded to failure.

RESULTS

For tunnel size specimens, load at ultimate failure was significantly greater for the 4.5-mm group compared with the 6-mm group (557.6 ± 48.5 N v 466.9 ± 42.2 N, P < .05). For tunnel location, load at ultimate failure was significantly greater for the centered-distal tunnel group compared with the eccentric-distal group (538.1 ± 70.2 N v 381.0 ± 68.6 N, P < .05).

CONCLUSIONS

A 4.5-mm tunnel in the coracoid provided greater strength for cortical button fixation than a 6-mm tunnel. In the distal coracoid, centered tunnels provided greater strength than eccentric tunnels.

CLINICAL RELEVANCE

When performing cortical button fixation at the coracoid process for coracoclavicular ligament reconstruction, a 4.5-mm tunnel provides greater fixation strength than a 6-mm tunnel. The base of the coracoid is more forgiving than the distal coracoid regarding location.

Chronic acromioclavicular joint dislocations treated by the GraftRope device

BACKGROUND AND PURPOSE

Surgical treatment of chronic acromioclavicular joint dislocations is challenging, and no single procedure can be considered to be the gold standard. In 2010, the GraftRope method (Arthrex Inc., Naples, FL) was introduced in a case series of 10 patients, showing good clinical results and no complications. We wanted to evaluate the GraftRope method in a prospective consecutive series.

PATIENTS AND METHODS

8 patients with chronic Rockwood type III-V acromioclavicular joint dislocations were treated surgically using the GraftRope method. The patients were clinically evaluated and a CT scan was performed to assess the integrity of the repair.

RESULTS AND INTERPRETATION

In 4 of the 8 patients, loss of reduction was seen within the first 6 weeks postoperatively. A coracoid fracture was the reason in 3 cases and graft failure was the reason in 1 case. In 3 of the 4 patients with intact repairs, the results were excellent with no subjective shoulder disability 12 months postoperatively. It was our intention to include 30 patients in this prospective treatment series, but due to the high rate of complications the study was discontinued prematurely. Based on our results and other recent reports, we cannot recommend the GraftRope method as a treatment option for chronic acromioclavicular joint dislocations.