Continuous Loop Double Endobutton Reconstruction for Acromioclavicular Joint Dislocation

The effect of number of knots per throw, knot technique, and suture type on strength properties of suspensory fixation button surgical procedures

Background

Previous studies of the cortical suspensory button (CSB) implant have analyzed fixation strength as a function of suture type and surgical technique, but knot configuration remains an area of interest. This study investigates 4-strand knot configurations in CSB suspensory fixation, specifically comparing the use of 2 separate knots with a single knot. We hypothesize that using 2 knots on the distal side of the CSB with #2 suture will yield the strongest and stiffest suspensory fixation.

Methods

Two types of knot configurations were compared: a single knot with all 4 suture strands versus 2 independent knots with 2 suture strands each (1 knot from inner strands and 1 knot from outer strands). They were tested using #2 or 2-0 suture, and at distal (on top of the button) or proximal (underneath the button) knot positions. Mechanical testing on the Instron measured ultimate failure load, elongation at failure, and stiffness. Statistical analyses (Shapiro-Wilk, unpaired Student's t-tests, and Chi-square tests) assessed differences in strength, stiffness, elongation, and failure mode between knot configurations within each CSB construct combination.

Results

With #2 suture, 2 knots across the CSB resulted in higher load to failure compared to 1 knot in both proximal (467.00 N vs. 554.66 N, P = .026) and distal (395.18 N vs. 526.51 N, P < .001) locations. Furthermore, 2 knots provided higher stiffness than 1 knot in both proximal (53.24 N/mm vs. 67.89 N/mm, P < .001) and distal (47.08 N/mm vs. 56.73 N/mm, P = .041) knot locations. However, using 2-0 suture showed no significant differences in failure load and stiffness regardless of knot location.

Conclusion

Using #2 suture and tying 2 independent knots across the CSB increased load to failure and stiffness compared to using only 1 knot regardless of knot position. Thus, if using #2 suture, it is recommended to tie 2 knots to enhance construct strength. However, with 2-0 suture, the number of knots did not impact construct strength. Therefore, if using 2-0 suture, 1 knot can be used to save time. Knot position did not significantly affect the strength or stiffness of the CSB construct, emphasizing the importance of considering knot prominence and surgical approach for determining knot location.

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.

Medial placement of trapezoid tunnel leads to higher reduction loss in acute acromioclavicular joint dislocation treated with anatomic coracoclavicular fixation

Aim

To analyze the association between clavicular tunnel positioning and postoperative reduction loss in patients with acute acromioclavicular (AC) joint dislocation treated with anatomic coracoclavicular (CC) fixation using double clavicular tunnels.

Methods

A retrospective review of patients with AC joint dislocation, treated with anatomic CC fixation using double clavicular tunnels, was conducted. Patients with pre-operative, immediate post-operative, and final follow-up Zanca-view X-rays were included. On each X-ray, the obtained measures included: distance from lateral border of clavicle to trapezoid and conoid tunnels, distance between tunnels, clavicle length, and CC distance of affected and un-affected sides. Loss of reduction was calculated as CC distance difference between immediate and final post-operative X-rays. Association between reduction loss and tunnel positioning was analyzed.

Results

Conoid, trapezoid and tunnel ratios were 24% ± 4, 15% ± 3, and 9% ± 2, respectively. Significant reduction loss was seen in 21(45.7%) patients. Significantly higher probabilities of reduction loss were associated with trapezoid tunnels placed medial to 24 mm (30.8% vs 65.0%, OR 4.2 (IC95%: 1.2-14.4), p: 0.024) or 15% of the clavicle length (32.1% vs 66.7%, OR 4.2 (IC 95%: 1.2-14.9), p: 0.025).

Conclusions

Trapezoid tunnels placed medial to 24 mm or 15% medial to clavicle length could lead to higher probabilities of significant reduction loss. These findings support the importance of clavicular tunnels' proper placement for decreasing significant reduction loss.

A Self-Designed Endobutton Installation Device for Coracoclavicular Stabilization in Acute Rockwood Type III Acromioclavicular Joint Dislocation

OBJECTIVE

Endobutton technique could provide flexible coracoclavicular (CC) stabilization for acromioclavicular joint (ACJ) dislocation and achieved good clinical outcomes. However, the difficult part of this technique was placement of the Endobutton to the coracoid base. In this study, we designed an Endobutton installation device to place the Endobutton at the coracoid base. And we examined the clinical and radiographic outcomes of patients with acute Rockwood type III ACJ dislocation repaired with Endobutton using this device.

METHODS

We designed an Endobutton installation device to place the Endobutton at the coracoid base to achieve CC stabilization. We retrospectively reviewed 42 patients with acute Rockwood type III ACJ dislocation who underwent CC stabilization with Endobuttons placed either using this novel device (group I, n = 19) or the traditional technique (CC stabilization without using special device, group II, n = 23) from January 2015 to April 2020. The two groups were compared regarding the operative time, intraoperative blood loss, and clinical and radiologic outcomes at final follow-up. The operation-related complications were also evaluated. The Student's t test and the Mann-Whitney U-test were used to compare differences in continuous variables. Differences in categorical variables were assessed with either the Pearson's chi-squared test or Fisher's exact test.

RESULTS

Forty-two patients were clinically followed up for a minimum of 12 months. Compared with group II, group I had a significantly shorter mean operative time (56.05 ± 7.82 min vs. 65.87 ± 7.43 min, p < 0.01) and significantly lesser mean intraoperative blood loss (67.89 ± 14.75 mL vs. 94.78 ± 25.01 mL, p < 0.01). At final follow-up, there were no significant differences between the two groups in the visual analog scale score for pain, Oxford Shoulder Score, Disabilities of the Arm, Shoulder, and Hand score, and postoperative CC distance of the affected side. Loss of reduction occurred in four patients in group I and three patients in group II (p = 0.68); there were no other operation-related complications in either group.

CONCLUSIONS

The Endobutton installation device makes placement of the Endobutton at the coracoid base easier and achieves satisfactory clinical and radiologic outcomes without additional complications in acute Rockwood type III ACJ dislocation.

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

PURPOSE

To compare the clinical efficacy of arthroscopic TightRope loop titanium button and clavicular hook plate in the treatment of acromioclavicular joint (ACJ) dislocation of Rockwood III/IV.

METHODS

A retrospective analysis of patients with ACJ dislocation in our hospital from January 2018 to December 2020 was conducted. The patients were assigned to be treated with arthroscopic TightRope loop titanium button (TR group) or clavicular hook plate (HP group). The preoperative, intraoperative and postoperative data and imaging findings of the two groups were compared.

RESULTS

A total of 58 eligible patients were enrolled in this study. Compared with HP group, TR group had shorter incision length and less blood loss during operation. Postoperative follow-up ranged from 12 to 24 months (mean 15.4 months). At 6 months and 12months postoperatively, compared with HP group, TR group had lower VAS and higher CMS, and the difference was statistically significant. At 12 months postoperatively, compared with HP group, TR group had lower ACJ gap and coracoclavicular joint(CCJ) distance, and the difference was statistically significant.In HP group, there were 3 cases of subacromial impact, 1 case of redislocation, 2 cases of traumatic arthritis and 2 cases of wound infection. There was 1 case of redislocation in TR group.

CONCLUSIONS

Compared with clavicular hook plate, arthroscopic TightRope loop titanium button is minimally invasive, safe and effective in the treatment of ACJ dislocation, and has a good trend in clinical application.

Comparison of Effectiveness and Safety in Treating Acute Acromioclavicular Joint Dislocation with Five Different Surgical Procedures: A Systematic Review and Network Meta-Analysis

This network meta-analysis aims to evaluate the comparative effectiveness and safety of suture anchors (SA), tendon grafts (TG), hook plates (HP), Tight-Rope (TR), and EndoButton (EB) in the treatment of acute acromioclavicular joint (ACJ) dislocation. The Embase, PubMed, and Web of Science databases were searched from their inception date to June 3, 2022. Studies included all eligible randomized controlled trials (RCTs) and cohort studies with the comparison of five different fixation systems among SA, TG, HP, TR, and EB were identified. All studies were reviewed, performed data extraction, and assessed the risk of bias independently by two reviewers. The primary outcomes are Constant-Murley score (CMS) improvement for assessing clinical efficacy, and complications. The second outcomes are visual analog scale (VAS) for assessing pain relief and the coracoclavicular distance (CCD) for assessing postoperative joint reduction. Version 2 of the revised Cochrane risk of bias tool for randomized trials (RoB 2) and the risk of bias in nonrandomized studies of interventions (ROBINS-I) were used to assess the RCTs and non-randomized trials, respectively. The continuous outcomes were presented as mean differences (MD), and risk ratios (OR) were used for dichotomous outcomes, both with 95% confidence intervals (CI). Surface under the cumulative ranking curves (SUCRA) results were calculated to offer a ranking of each intervention. We identified 31 eligible trials, including 1687 patients in total. HP showed less CMS improvement than TR and EB in both the Network Meta-analysis (NMA) and pairwise meta-analysis. HP also showed less CMS improvement than SA in NMA. For pain relief, HP performed worse than TR both in pairwise meta-analysis and NMA. No significant differences were found for the measured value of CCD. Both TR and EB showed a lower incidence of complications than HP in pairwise meta-analysis. The rank of SUCRA for CMS improvement was as follows: SA, TR, EB, TG, and HP; for pain relief: TR, EB, TG, SA, and HP; for CCD: HP, TR, SA, EB, and TG. For complications, HP showed the highest rank, followed by TG, EB, TR, and SA. SA shows better clinical effectiveness and reliable safety in the treatment of acute ACJ dislocation. Although HP is the most widely used surgical option currently, it should be carefully taken into consideration for its high incidence of complications.

Open coraco-clavicular ligament reconstruction (CCLR) in treatment of displaced distal clavicle fractures has low complication rate and excellent union rate: a systematic review

BACKGROUND

It is well established that non-operative treatment of displaced distal clavicle fractures (DDCF) leads to a high non-union rate. A number of open surgical treatments in the past have shown good to excellent outcomes including shoulder function and union rate. Despite this there is no consensus on the outcome of open coraco-clavicular ligament reconstruction (CCLR). The aim of this systematic review was to assess the union rate, complications and shoulder function of open CCLR techniques in the treatment of DDCF.

PATIENTS AND METHODS

A review of the online databases MEDLINE and Embase was conducted on 1 January 2021 according to PRISMA guidelines. The review was registered prospectively in the PROSPERO database. Clinical studies reporting union rate, complications and shoulder function were included. The studies were appraised using the Methodological Index for Non-Randomized Studies (MINORS) tool.

RESULTS

The search strategy identified 18 studies eligible for inclusion with a total of 330 patients. These included 12 retrospective case series and 5 nonrandomized retrospective comparative studies and one RCT. All but one study reported on shoulder function, while all the studies reported on union rate and complications. The overall shoulder function was good to excellent using Constant-Murley score. The overall union rate was 97.6% and complication rate was 7.6%.

CONCLUSION

Open CCLR for displaced distal clavicle fractures that have a disruption of CC ligament, is a reliable treatment with excellent union rate and good to excellent shoulder functional scores.

LEVEL OF EVIDENCE

IV; Systematic review.

Surgical management of acute, high-grade acromioclavicular joint separations: a systematic review

Background

While a number of treatment options exist for repair of acute, high-grade acromioclavicular joint (ACJ) separation, none have emerged as the standard of care. The purpose of this study was to systematically review the literature on surgical treatment of acute, high-grade (Rockwood grades III-V) ACJ separations in order to compare outcomes between direct fixation and tendon graft ligament reconstruction.

Methods

A systematic review of the literature evaluating outcomes for acute ACJ separation treatment with direct fixation or free biologic tendon graft reconstruction was performed. The following databases were examined: the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, PubMed (1980-2021), and Embase (1980-2021). Studies were included if they reported a mean time to surgery as <6 weeks, contained >10 patients with a minimum 1-year follow-up, and reported clinical or radiographic outcomes.

Results

A total of 52 studies met the inclusion criteria. Seven studies reported outcomes following tendon graft ligament reconstruction (n = 128 patients). There were multiple methods of direct fixation. Thirty-three studies utilized suture button constructs (n = 1138), 16 studies used hook plates (n = 567), 2 studies used coracoclavicular screws (n = 94), 2 studies used suture fixation (n = 93), 2 studies used suture anchor (n = 55), 2 studies used suture cerclage fixation (n = 87), 1 used single multistrand titanium cable (n = 24), and 1 used K wire (n = 11). The mean follow-up Constant scores ranged from 77.5 to 97.1 in the fixation group compared to 90.3-96.6 in the tendon graft group. The mean visual analog scale scores ranged from 0 to 4.5 in the fixation group and 0.1-1 in the tendon graft group. Net CC distance ranged from 17.5 to 3.6 mm in the fixation group and 7.4-4 mm in the tendon graft group. The revision rates ranged from 0.0% to 18.18% in the direct fixation group and 5.88%-17% in the tendon graft group.

Conclusion

Direct fixation and tendon graft reconstruction for management of acute, high-grade ACJ separations have similar patient subjective and radiographic outcomes, as well as complication and revision rates at a minimum 1-year follow-up.

Accelerated rehabilitation in treating neer type V distal clavicle fractures using anatomical locking plates with coracoclavicular ligament augmentation

Background

There is still no gold standard treatment for Neer type V distal clavicle fractures. This study was designed to evaluate the therapeutic effects of accelerated rehabilitation in treating Neer type V fractures using anatomical locking plate (ALP) fixation with additional coracoclavicular (CC) ligament augmentation.

Methods

In this retrospective study, patients who underwent ALP fixation with additional suture anchor fixation of acute Neer type V distal clavicle fracture from January 2016 to January 2021 were reviewed. Injury radiography and computed tomography (CT) were performed to determine the Neer classification. All patients performed standardized early rehabilitation exercises after surgery and were followed up for more than 12 months. The Constant-Murley score (CMS); the disabilities of the arm, shoulder, and hand (DASH) questionnaire; visual analog scale (VAS); and the percentage of modified CC distance (MCCD%) were evaluated at the last follow-up.

Results

Thirty-two patients were included in this study. The mean follow-up time was 31.1 ± 10.4 months. All patients achieved bone union 6-8 weeks (7.2 ± 0.7 weeks) after surgery and were allowed to return to normal daily life. No surgery-related complications occurred in any case. The MCCD% value at the last follow-up (104.7% ± 8.5%) significantly decreased compared with preoperative MCCD% value (162.8% ± 7.2%) (p < 0.001), indicating that all patients achieved ideal fracture reduction. And all patients obtained satisfactory shoulder joint function with a mean CMS of 97.1 ± 2.6, a mean DASH score of 1.6 ± 1.3, and a mean VAS score of 0.4 ± 0.6.

Conclusion

This study has demonstrated that ALP fixation with additional suture anchor fixation is a promising strategy for accelerated rehabilitation in treating patients with Neer type V fracture.

Early loss of radiographic reduction after acute acromioclavicular joint reconstruction: Comparison of open Double Endobutton fixation vs. Nottingham Surgilig

INTRODUCTION

Surgical treatment is usually recommended for the acute unstable acromioclavicular joint (ACJ) dislocations. Among the wide variety of different surgical techniques, the Double Endobutton and the Nottingham Surgilig technique are two of the most widely acceptable and well described techniques. The aim of this study was to offer a direct comparison of the above techniques in question, analysing the patients outcomes and assessing the risk of early loss of radiographic reduction.

MATERIALS AND METHODS

A total of 48 patients who met the inclusion criteria were included in the study. Patients were categorised in two groups (Endobutton and Nottingham Surgilig group) and post operative assessment of the patients was performed using the Oxford Shoulder (OSS) and Constant Murley (CMS) scores. Patient demographics, hand dominance, ACJ classification and co-morbidities were included in the analysis and radiographic evaluation was conducted for both groups.

RESULTS

Both techniques provide a good outcome in the management of unstable ACJ dislocations but the risk of early radiographic failure remains higher in the double Endobutton technique (26% vs. 17.39% for the Nottingham Surgilig group). Factors such as patients' demographics, hand dominance, co-morbidities and grade of ACJ separation do not seem to contribute to radiographic loss of reduction, whereas the incorrect positioning of the coracoid endobutton is a significant factor predisposing to early radiographic failure, P < 0.001.

DISCUSSION

The incidence of early loss of radiographic reduction still remains high in both groups. In order to reduce this common complication, accurate placement of the coracoid endobutton under fluoroscopic intra-operative control is strongly recommended.

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.

The Morphology of the Acromioclavicular Joint Does Not Influence the Postoperative Outcome Following Acute Stabilization—A Case Series of 81 Patients

Purpose

To specifically evaluate the influence of the acromioclavicular (AC)-joint morphology on the outcome after arthroscopically assisted coracoclavicular (CC) stabilization surgery with suspensory fixation systems and to investigate whether an additional open AC-joint reduction and AC cerclage improves the clinical outcome for patients with certain morphologic AC-joint subtypes.

Methods

Patients with an acute acromioclavicular joint injury, who underwent arthroscopically assisted CC stabilization with suspensory fixation systems with or without concomitant AC cerclage between January 2009 and June 2017 were identified and included in this retrospective cohort analysis. AC-joint morphology was assessed on preoperative radiographs and categorized as “flat” or “non-flat” (“oblique”/“curved”) subtypes. After a minimum of 2 years of follow-up, postoperative Single Assessment Numeric Evaluation (SANE), American Shoulder and Elbow Surgeons (ASES), and visual analog scale (VAS) scores for pain were collected. A subgroup analysis of clinical outcomes depending on the surgical technique and morphological subtype of the AC joint was performed.

Results

Eighty-one patients (95% male, mean age 35 ± 12 years) could be included at a mean follow-up of 57 ± 14 months. Radiographic assessment of AC-joint morphology showed 24 (30%) cases of flat type, 38 (47%) cases of curved type, and 19 (23%) cases of oblique morphology. Postoperatively, no clinically significant difference could be detected after the treatment of AC joint injury via CC stabilization with or without concomitant AC cerclage (VAS_rest: P = .067; VAS_max: P = .144, ASES: P = .548; SANE: P = .045). No clinically significant differences were found between the surgical techniques for the flat morphologic subtype (VAS_rest: P = .820; VAS_max: P = .251; SANE: P = .104; ASES: P = .343) or the non-flat subtype (VAS_res: P = .021; VAS_max: P = .488; SANE: P = .243, ASES: P = .843).

Conclusions

In arthroscopically assisted AC stabilization surgery with suspensory fixation systems for acute AC-joint injury, the AC-joint morphology did not influence the postoperative outcome, independent of the surgical technique. No clinical benefit of performing an additional horizontal stabilization could be detected in our collective at mid-term follow-up.

Level of Evidence

Level IV, therapeutic case series.

Criteria for return to play after operative management of acromioclavicular joint separation: a systematic review

Background

Acromioclavicular (AC) joint separation is a common cause of shoulder injury among athletes. High-grade injuries may require operative fixation, and comprehensive return-to-play guidelines have not yet been established. The purpose of this study was to summarize criteria for return to play after operative management of AC joint separation.

Methods

A systematic review of the literature was performed from January 1999 to April 2020 to evaluate clinical evidence regarding criteria for return to play after operative management of isolated AC joint separation.

Results

Sixty-three studies with at least 1 explicitly stated return-to-play criterion were identified out of an initial database search of 1253 published articles. Eight separate categories of return-to-play criteria were identified, the most common of which was time from surgery (95.2%). Return-to-play timelines ranged from 2 to 12 months, the most common timeline being 6 months (37.8%). Only 4 (6.3%) studies used conditional criteria to guide return to play, which included range of motion, strength, clinical stability, radiographic stability, functional assessment, safety assessment, and hardware removal.

Conclusion

Most published studies use only time-based criteria for return to play after surgery for AC joint separation, and only a small number of studies use additional subjective or objective criteria. While this systematic review helps provide a foundation for developing a comprehensive return-to-play checklist, further investigation is needed to establish safe and effective guidelines that will enable athletes to safely return to sport and minimize the recurrence of injury.

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.

Does coracoclavicular augmentation additional to hook plate fixation provide benefits in acute unstable acromioclavicular dislocation? A meta-analysis

Background

Acromioclavicular joint (ACJ) dislocation is a common shoulder injury. In treating acute unstable ACJ dislocation, a hook plate (HP) is a straightforward and popular option for ensuring proper reduction and rigid fixation while promoting AC and coracoclavicular (CC) ligament healing. Surgeons typically remove the HP to prevent subacromial impingement and acromial osteolysis; however, concerns about redislocation after implant removal remain. Therefore, additional CC augmentation may be helpful in combination with HP fixation. The aim of this meta-analysis is to compare the outcomes and complications of HP fixation with or without additional CC augmentation for acute unstable ACJ dislocation.

Methods

We searched the PubMed, EMBASE, and Web of Science databases for relevant case–control studies. The primary outcomes were patient-reported outcome measures; the secondary outcomes were pain measured using a visual analog scale (VAS), CC distance (CCD), and complications. Continuous data were assessed using weighted standardized mean differences (SMDs) with 95% confidence intervals (CIs), and dichotomous data were evaluated with Mantel–Haenszel odds ratio (ORs) with 95% CIs.

Results

We analyzed one randomized control trial and four case–control studies comparing HP fixation with or without CC augmentation. A total of 474 patients with Rockwood type III or V ACJ dislocation were included. We found no differences in Constant–Murley score (SMD, − 0.58, 95% CI − 1.41 to 0.26; P = 0.18), American Shoulder and Elbow Surgeons score (SMD, 0.21, 95% CI − 0.10 to 0.52; P = 0.19), University of California at Los Angeles shoulder rating scale score (SMD, − 0.02, 95% CI − 1.27 to 1.23; P = 0.97), or VAS pain score (SMD, 0.36, 95% CI − 0.16 to 0.88; P = 0.17) between groups. The CC augmentation group had lower odds of osteolysis (OR, 0.27, 95% CI 0.10 to 0.74; P = 0.01) and a shorter CCD (SMD, − 0.29, 95% CI − 0.57 to − 0.01; P = 0.04).

Conclusion

HP fixation with CC augmentation is preferable for acute unstable ACJ dislocations. Although CC augmentation did not provide additional benefits related to functional outcomes or pain, it resulted in greater reduction maintenance after implant removal and a 73% lower risk of acromial osteolysis.

Trial registration

PROSPERO (CRD42021271118).

Low rate of substantial loss of reduction immediately after hardware removal following acromioclavicular joint stabilization using a suspensory fixation system

PURPOSE

To evaluate immediate loss of reduction in patients undergoing hardware removal after arthroscopically assisted acromioclavicular (AC) joint stabilization using a high-tensile suture tape suspensory fixation system and to identify risk factors associated with immediate loss of reduction.

MATERIALS AND METHODS

Twenty-two consecutive patients with a mean age of 36.4 ± 12.6 years (19-56), who underwent hardware removal 18.2 ± 15.0 months following arthroscopically assisted stabilization surgery using a suspensory fixation system for AC joint injury between 01/2012 and 01/2021 were enrolled in this retrospective monocentric study. The coracoclavicular distance (CCD) as well as the clavicular dislocation/acromial thickness (D/A) ratio were measured on anterior-posterior radiographs prior to hardware removal and immediately postoperatively by two independent raters. Loss of reduction, defined as 10% increase in the CCD, was deemed substantial if the CCD increased 6 mm compared to preoperatively. Constitutional and surgical characteristics were assessed in a subgroup analysis to detect risk factors associated with loss of reduction.

RESULTS

Postoperatively, the CCD significantly increased from 12.6 ± 3.7 mm (4.8-19.0) to 14.5 ± 3.3 mm (8.7-20.6 mm) (p < 0.001) while the D/A ratio increased from 0.4 ± 0.3 (- 0.4-0.9) to 0.6 ± 0.3 (1.1-0.1) (p = 0.034) compared to preoperatively. In 10 cases (45%), loss of reduction was identified, while a substantial loss of reduction (> 6 mm) was only observed in one patient (4.5%). A shorter time interval between index stabilization surgery and hardware removal significantly corresponded to immediate loss of reduction (11.0 ± 5.6 vs. 30.0 ± 20.8 months; p = 0.007), as hardware removal within one year following index stabilization was significantly associated with immediate loss of reduction (p = 0.027; relative risk 3.4; odds ratio 11.67).

CONCLUSIONS

Substantial loss of reduction after hardware removal of a high-tensile suture tape suspensory fixation system was rare, indicating that the postoperative result of AC stabilization is not categorically at risk when performing this procedure. Even though radiological assessment of the patients showed a statistically significant immediate superior clavicular displacement after this rarely required procedure, with an increased incidence in the first year following stabilization, this may not negatively influence the results of ACJ stabilization in a clinically relevant way.

LEVEL OF EVIDENCE

IV.

Mid-clavicle fracture with dislocation of the ipsilateral acromioclavicular joint treated with Endobutton system: A case report and review of the literature

RATIONALE

Acromioclavicular joint (ACJ) dislocation combined with ipsilateral midclavicular fracture is extremely unusual and is a high-energy injury to the shoulder. A review of the literature divides the treatment of clavicular fractures is divided into nonsurgical treatment, plates, and intramedullary nailing, while the options for ACJ dislocation are elastic fixation and rigid fixation. However, there is still a lack of consensus about the most appropriate way to treat this shoulder injury. This case report involves a mid-clavicle fracture with dislocation of the ipsilateral ACJ, which was classified as type V according to Rockwood classification.

PATIENT CONCERNS

A 65-year-old man came to the emergency department after a traffic accident in which he was driving a motorcycle that collided with another motorcycle and his right shoulder collided directly with the ground. Digital radiography (DR) and computed tomography (CT) scans of the right shoulder joint showed mid-clavicle fracture with dislocation of the ipsilateral ACJ, which was classified as type V according to Rockwood classification.

DIAGNOSES

The diagnosis of mid-clavicle fracture with dislocation of the ipsilateral ACJ was confirmed by DR and CT.

INTERVENTIONS

The patient was treated with a clavicle plate combined with the double Endobutton technique.

OUTCOMES

After a 6-month follow up, the patient had excellent results for shoulder range of motion and functional. The patient's Constant-Murley score is 92.

LESSONS

Mid-clavicular fracture with a high-energy injury is highly suspicious and requires perfect shoulder CT or bilateral shoulder stress position DR to confirm whether there is a combined ACJ dislocation.

Anatomic reconstruction of the acromioclavicular joint provides the best functional outcomes in the treatment of chronic instability

PURPOSE

To systematically review the outcomes of surgical treatments of chronic acromioclavicular joint dislocation.

METHODS

Studies were identified by electronic databases (Ovid, PubMed). All studies reporting functional and radiological outcomes of surgical treatments of chronic acromioclavicular joint dislocations were included. Following data were extracted: authors and year, study design, level of evidence, number of patients, age, classification of acromioclavicular joint dislocation, time to surgery, surgical technique, follow-up, clinical and imaging outcomes, complications and failures. Descriptive statistics was used, when a data pooling was not possible. Comparable outcomes were pooled to generate summary outcomes reported as frequency-weighted values. Quality appraisal was assessed through the MINORS checklist.

RESULTS

Fourty-four studies were included for a total of 1020 shoulders. Mean age of participants was 38 years. Mean follow-up was 32.9 months. Arthroscopic techniques showed better results than open approach (p < 0.0001). Synthetic reconstructions demonstrated better functional outcomes compared to internal fixation and biologic techniques (p < 0.0001). Among biologic techniques, combined coracoclavicular and acromioclavicular ligaments reconstruction showed better Constant (p = 0.0270) and ASES (p = 0.0113) scores compared to isolated coracoclavicular ligaments reconstruction; anatomic biologic non-augmented graft reconstruction showed better Constant (p < 0.0001), VAS (p < 0.0001) and SSV (p = 0.0177) results compared to augmented techniques. No differences in functional outcomes could be found between anatomic biologic non-augmented graft versus synthetic reconstructions. Overall, methodological quality of the included studies was low.

CONCLUSION

Anatomic reconstructions, both synthetic and biologic, showed the best functional results.

LEVEL OF EVIDENCE

IV.

Biologic and synthetic ligament reconstructions achieve better functional scores compared to osteosynthesis in the treatment of acute acromioclavicular joint dislocation

PURPOSE

To systematically review the outcomes of surgical treatments of acute acromioclavicular joint dislocation.

METHODS

Studies were identified by electronic databases (Ovid, PubMed). All studies reporting functional and radiological outcomes of surgical treatments of acute acromioclavicular joint dislocations were included. Following data were extracted: authors and year, study design, level of evidence, number of patients, age, classification of acromioclavicular joint dislocation, time to surgery, surgical technique, follow-up, clinical and imaging outcomes, complications, and failures. Descriptive statistics was used, when a data pooling was not possible. Comparable outcomes were pooled to generate summary outcomes reported as frequency-weighted values. Quality appraisal was assessed through the MINORS checklist.

RESULTS

One hundred and thirty-three studies were included for a total of 4473 shoulders. Mean age of participants was 36.9 years. Mean follow-up was 42.06 months. Arthroscopy showed better ASES (p < 0.0001) and lower VAS pain score (p = 0.0249) compared to an open approach. Biologic and synthetic reconstructions demonstrated better results over osteosynthesis techniques. Biologic techniques showed overall better Constant (p = 0.0001) and DASH (p = 0.0215) scores, while synthetic reconstruction showed better UCLA score (p = 0.0001). Among suture buttons, triple button showed overall better results in Constant (p = 0.0001) and VAS (p = 0.0001) scores, while better results in DASH score (p = 0.0003) were achieved by 2 double button techniques. Overall, the level of evidence was low.

CONCLUSION

Biological and synthetic reconstructions achieved better functional scores compared to osteosynthesis. Among suture buttons, the triple button showed better functional performance.

LEVEL OF EVIDENCE

IV.

Results of Arthroscopic Treatment of Acute Posterior Cruciate Ligament Avulsion Fractures With Suspensory Fixation

PURPOSE

This study aimed to evaluate the clinical outcomes for arthroscopic treatment for acute posterior cruciate ligament (PCL) avulsion fractures with a suspensory technique.

METHODS

A total of 30 acute (<3 weeks) isolated PCL tibial avulsion fractures were fixed under arthroscopy using the Endobutton device. After arthroscopic exploration and reduction of the bony fragment, a single tibia tunnel was established; then, the titanium button was guided through the tunnel and flipped onto the bony fragment to stabilize the fracture. Finally, an interference screw was squeezed into the tunnel to fix the end of the loop. Clinical and functional outcomes were evaluated using the Lysholm score, the 2000 International Knee Documentation Committee (IKDC) subjective score, and the IKDC examination form.

RESULTS

The mean follow-up time was 32 months (range, 24-47 months). The mean age of the patients was 41 years (range, 21-65 years). All patients achieved bony union and regained satisfactory knee function. No popliteal neurovascular complications or implant loosening was observed. The mean Lysholm score increased from 20.9 ± 7.0 before operation to 97.1 ± 2.7 at the final follow-up. The mean 2000 IKDC subjective score improved from 17.2 ± 5.2 to 96.8 ± 2.6. The IKDC examination grade also improved significantly.

CONCLUSIONS

This suspensory technique under arthroscopy is a simple, safe, and minimally invasive treatment for PCL tibial avulsion fracture. Suspensory fixation resulted in satisfactory outcomes, including good knee stability and fracture union; this technique can be a reliable alternative to various surgical methods.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Arthroscopic-Assisted Coracoclavicular Ligament Reconstruction: Clinical Outcomes and Return to Activity at Mean 6-Year Follow-Up

PURPOSE

To report clinical and functional outcomes including return to preinjury activity level following arthroscopic-assisted coracoclavicular (CC) ligament reconstruction (AA-CCR) and to determine associations between return to preinjury activity level, radiographic outcomes, and patient-reported outcomes following AA-CCR.

METHODS

A institutional registry review of all AA-CCR using free tendon grafts from 2007 to 2016 was performed. Clinical assessment included Single Assessment Numeric Evaluation (SANE) score and return to preinjury activity level at final follow-up. Treatment failure was defined as (1) revision acromioclavicular stabilization surgery, (2) unable to return to preinjury activity level, or (3) radiographic loss of reduction (RLOR, >25% CC distance compared with contralateral side). SANE scores, return to activity, and RLOR were compared between patients within each category of treatment failure, by grade of injury, and whether concomitant pathology was treated.

RESULTS

There were 88 patients (89.8% male) with mean age of 39.6 years and minimum 2-year clinical follow-up (mean 6.1 years). Most injuries were Rockwood grade V (63.6%). Mean postoperative SANE score was 86.3 ± 17.5. Treatment failure occurred in 17.1%: 8.0% were unable to return to activity, 5.7% had RLOR, and 3.4% underwent revision surgery due to traumatic reinjury. SANE score was lower among patients who were unable to return to activity compared with those with RLOR and compared with nonfailures (P = .0002). There were no differences in revision surgery rates, return to activity, or SANE scores according to Rockwood grade or if concomitant pathology was treated.

CONCLUSIONS

AA-CCR with free tendon grafts resulted in good clinical outcomes and a high rate of return to preinjury activity level. RLOR did not correlate with return to preinjury activity level. Concomitant pathology that required treatment did not adversely affect outcomes. Return to preinjury activity level may be a more clinically relevant outcome measure than radiographic maintenance of acromioclavicular joint reduction.

LEVEL OF EVIDENCE

IV (Case Series).

Better Radiographic Reduction and Lower Complication Rates With Combined Coracoclavicular and Acromioclavicular Ligament Reconstruction Than With Isolated Coracoclavicular Reconstruction

PURPOSE

To determine whether combined acromioclavicular (AC) ligament reconstruction and coracoclavicular (CC) ligament reconstruction without bone tunnels would improve radiographic reduction maintenance and complication rates for type III to V AC dislocations.

METHODS

This single-institution retrospective study analyzed all patients who underwent a hybrid synthetic/graft wrap CC reconstruction without tunnels with additional AC reconstruction/repair from January 2013 to August 2019. This 26-patient cohort was compared with a 1:1 sex- and age-matched control group who underwent CC reconstruction without AC reconstruction. CC distances on postoperative radiographs were compared with normal contralateral shoulders.

RESULTS

Of the 93 patients who underwent AC reconstructive surgery during this time period, 26 patients (96% male) met the inclusion criteria. The AC/CC cohort had 23.5% type III injuries, 23.1% type IV injuries, and 53.8% type V injuries, similar to the control group. Final radiographs of the operative shoulder's CC distance were (mean ± standard deviation) 0.9 ± 4.0 mm greater than that of the contralateral shoulder (9.6 ± 8.7 mm) in the AC/CC cohort. Final radiographs of the operative shoulder's coracoclavicular distance were 4.0 ± 4.7 mm greater than that of the contralateral shoulder (13.3 ± 9.3 mm) in the CC control group, a significant difference (P = .014). The AC/CC reconstruction group had fewer patients with a loss of reduction >5 mm (11.5% versus 38.5%, P = .025). The complication rate in the CC control group was higher than in the AC/CC cohort (30.7% versus 7.7%, P = .035). The reoperation rate was also greater in the CC control group (8 versus 1, P = .010).

CONCLUSION

This cohort study shows that the addition of AC reconstruction to CC reconstruction using synthetic tapes/grafts or allograft tissues without bone tunnels significantly improves durable radiographic outcomes, diminishes complication rates, and improves reoperation rates.

LEVEL OF EVIDENCE

III, retrospective comparative study.

Risk factors related to the loss of reduction after acromioclavicular joint dislocation treated with the EndoButton device

Background

Anatomic ligament reconstruction using the EndobutBon device has been proven an effective technique for the management of acute acromioclavicular (AC) joint dislocation. The aim of this study was to analyze the risk factors causing loss of reduction after AC joint dislocation treated with the EndoButton device for open procedures.

Methods

A total of 107 patients who met the inclusion and excluded criteria finally were enrolled. We retrospectively analyzed the clinical tests, imaging data, and postoperative rehabilitation of patients in a stable reduction group and a loss of reduction group.

Results

Among all patients included in the study, the incidence of reduction failure was 14%. Univariate analysis identified that the time between injury to surgery, double or triple EndoButton, coracoid EndoButton position, weight-bearing time of the upper limb, and osteolysis had statistically significant associations with loss of reduction for the AC joint (P=0.022, 0.002, 0.000, 0.000, and 0.000 respectively). By using multivariate logistic regression analysis, we found that coracoid EndoButton position (P=0.002), weight-bearing time of the upper limb (P=0.011), and osteolysis (P=0.036) were the significant independent risk factors related to the loss of reduction after AC joint dislocation treated with the EndoButton device used with open procedures.

Conclusions

In order to reduce the incidence of reduction failure and improve the prognosis of patients, more accurate placement of EndoButton plates in surgery and guidance for patients in completing planned rehabilitation training are needed.

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.

Surgical techniques for management of acromioclavicular joint separations: review and update for radiologists

Imaging plays a central role in the postoperative management of acromioclavicular (AC) joint separations. There are more than 150 described techniques for the surgical management of AC joint injuries. These procedures can be categorized as varying combinations of the following basic techniques: a) soft-tissue repair, b) trans-articular AC joint fixation, c) coracoclavicular (CC) fixation, d) non-anatomic reconstruction of the CC ligaments, e) anatomic reconstruction of the CC ligaments, f) distal clavicle resection, and g) dynamic muscle transfer. The goals of this article are to describe the basic techniques for the surgical management of AC joint separations with an emphasis on technique-specific complications and postoperative imaging assessment.

Early clinical results of minimally invasive coracoclavicular ligament reconstruction can be maintained at a minimum of five years' follow-up

AIMS

There is a lack of long-term data for minimally invasive acromioclavicular (AC) joint repair. Furthermore, it is not clear if good early clinical results can be maintained over time. The purpose of this study was to report long-term results of minimally invasive AC joint reconstruction (MINAR) and compare it to corresponding short-term data.

METHODS

We assessed patients with a follow-up of at least five years after minimally invasive flip-button repair for high-grade AC joint dislocation. The clinical outcome was evaluated using the Constant score and a questionnaire. Ultrasound determined the coracoclavicular (CC) distance. Results of the current follow-up were compared to the short-term results of the same cohort.

RESULTS

A total of 50 patients (three females, 47 males) were successfully followed up for a minimum of five years. The mean follow-up was 7.7 years (63 months to 132 months). The overall Constant score was 94.4 points (54 to 100) versus 97.7 points (83 to 100) for the contralateral side showing a significant difference for the operated shoulder (p = 0.013) The mean difference in the CC distance between the operated and the contralateral shoulder was 3.7 mm (0.2 to 7.8; p = 0.010). In total, 16% (n = 8) of patients showed recurrent instability. All these cases were performed within the first 16 months after introduction of this technique. A total of 84% (n = 42) of the patients were able to return to their previous occupations and sport activities. Comparison of short-term and long-term results revealed no significant difference for the Constant Score (p = 0.348) and the CC distance (p = 0.974).

CONCLUSION

The clinical outcome of MINAR is good to excellent after long-term follow-up and no significant differences were found compared to short-term results. We therefore suggest this is a reliable technique for surgical treatment of high-grade AC joint dislocation. Cite this article: Bone Joint J 2020;102-B(7):918-924.

Anatomic and non-anatomic reconstruction improves post-operative outcomes in chronic acromio-clavicular instability: a systematic review

PURPOSE

To systematize the surgical outcomes of anatomic and non-anatomic reconstruction in patients with chronic acromio-clavicular joint (ACJ) instability and determine which technique is superior.

METHODS

This review was conducted according to the PRISMA guidelines. PubMed and Cochrane Library databases were searched up to April 30th, 2018 for original articles that assessed the outcomes of one or more surgical techniques of anatomic and non-anatomic reconstruction in patients with chronic ACJ instability. The Methodological Index for Non-randomized Studies (MINORS) was used to assess study quality. Pre-to-post meta-analysis was performed for both anatomic and non-anatomic reconstructions.

RESULTS

Twenty-eight studies were included comprising 799 patients (mean age of 36.6 years old and 84% males) with a mean follow-up of 34.6 months (range 13 to 74). Surgical techniques included anatomic (tendinous or synthetic grafts/constructs) and non-anatomic reconstruction (Weaver-Dunn or Modified Weaver-Dunn, conjoined tendon transfer, or temporary hook plate). There were significant pre-to-post improvements on the constant score with an average improvement ranging from 11.1 to 50.7 (p < 0.01). Average failure rate was 7.6% (7.5% for anatomic and 8.5% for non-anatomic reconstruction). Non-comparative studies had a mean MINORS score of 9 points (out of 16) and comparative studies 17 (out of 24) with excellent interrater agreement (k = 0.910).

CONCLUSION

Both anatomic and non-anatomic ACJ reconstructions provide significant post-operative improvements, but definitive conclusions on optimal technique remain elusive. Notwithstanding, comparative studies support the use of anatomic ACJ reconstruction which should be preferably used. However, until superiority is demonstrated by robust studies, surgeons should supplement their decision-making with experience and patient preference.

LEVEL OF EVIDENCE

IV.

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.

Percutaneous endobutton fixation of acute acromioclavicular joint injuries and lateral clavicle fractures

INTRODUCTION

This paper describes a novel technique developed by the senior author to address acute acromioclavicular joint (ACJ) dislocations and certain distal clavicle fractures.

METHODS

The procedure employs a four strand, single tunnel, double endobutton repair performed entirely percutaneously, without any arthroscopic guidance or deep surgical dissection.

RESULTS

We present the preliminary results from our series of 6 consecutive patients performed over a period of 18 months. The mean length of surgery was 36min (range 32-40) and the mean correction of coracoclavicular (CC) distance achieved was 12.6 mm (range 10.3-14.1). There was no restriction of movement in any of the patients post-operatively and their average QuickDASH scores at final follow-up was 4.2 (range 0-6.8).

CONCLUSION

Results in the present series were at least comparable to those for other techniques, validating percutaneous treatment as a solution for acute ACJ dislocations.

Acute Fixation of Type IV and V Acromioclavicular Separations: An Internal Splint Technique

Background:

There is no standard method for the surgical treatment of acromioclavicular (AC) joint separations. Current techniques have associated complications, including need for device removal, coracoid fracture, and inadequate reduction.

Purpose:

To evaluate the clinical outcomes of an internal splint technique without graft augmentation or rigid fixation to treat acute Rockwood type IV and V AC joint injuries.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective analysis was performed of 26 patients who underwent a novel internal splint fixation technique between 2011 and 2016. Patients had type IV (n = 2) and type V (n = 24) acute AC separations. The mean time to surgery was 13.7 days (range, 1-28 days). The surgical technique included an open approach with coracoclavicular suture and tape fixation and AC suture fixation. Range of motion, strength, and radiographs were evaluated after surgery. Patient follow-up included the DASH (Disabilities of the Arm, Shoulder and Hand) questionnaire at a mean 3.3 years postoperatively (range, 6 months–8.6 years). DASH questionnaires were obtained for all patients via email. Patients were also surveyed on cosmetic appearance and willingness to undergo the operation again.

Results:

All patients regained full strength and range of motion following surgery. All postoperative radiographs demonstrated well-maintained reduction of the AC joint. The mean DASH score was 3.4 at final follow-up, and 23 of 26 respondents were satisfied with their postoperative shoulder appearance. There were no reoperations, and all patients stated that they would have the operation again given the same circumstances.

Conclusion:

The results of this study demonstrate a reliable new technique for acute fixation of type IV or V AC joint injuries via an internal splint construct. This technique enables reduction in the coronal and sagittal planes without the need for graft augmentation or a rigid implant, allowing healing of the coracoclavicular and AC ligaments.

Clinical outcomes of a single-tunnel technique for coracoclavicular and acromioclavicular ligament reconstruction

BACKGROUND

A large number of surgical techniques have been described to treat acromioclavicular (AC) joint separations. Despite the high success rates with double-tunnel reconstruction, this method has been associated with the risk of coracoid and clavicle fractures. This study aimed to evaluate the outcomes of the first cohort of patients who underwent single-tunnel AC and coracoclavicular (CC) ligament reconstruction. It was hypothesized that this technique would result in maintenance of reduction and a minimal risk of fracture of the coracoid and clavicle.

METHODS

All patients who underwent single-tunnel AC joint reconstruction between 2012 and 2015 via the technique with 2-year follow-up were included. Objective outcomes recorded were maintenance of reduction as measured by the CC distance on radiographs, shoulder range of motion, strength, return to sports, and complications. Subjective outcomes included maintenance of reduction on visual inspection and various patient-reported outcomes.

RESULTS

Seventeen patients were included with a mean age of 41 ± 12 years. Separation types included types III, IV, and V. The mean follow-up period was 29 ± 9 months (range, 16-45 months). The CC distance improved from 37.4 to 30.0 mm on plain radiographs (P = .006), the American Shoulder and Elbow Surgeons score improved from 67.0 to 90.1 (P = .094), and the Single Assessment Numeric Evaluation score improved from 30.5 to 91.1 (P = .025). Reduction on visual inspection was maintained in 16 patients (94.1%). Regarding sports participation, 14 patients (82.4%) returned to their preinjury level. The most common complication was a prominent suture knot stack, occurring in 3 patients (17.6%), which was removed in all 3 in a second procedure. There were no clavicle or coracoid fractures.

CONCLUSION

The described technique results in satisfactory objective and patient-reported outcomes and return to sports while avoiding coracoid and clavicle fractures.

A prospective study of coracoclavicular ligament reconstruction with autogenous peroneus longus tendon for acromioclavicular joint dislocations

BACKGROUND

Anatomic coracoclavicular (CC) ligament reconstruction (ACCR) provides good outcomes for Rockwood type III and VI acromioclavicular (AC) joint dislocations. Various grafts have been used, but complications from graft harvesting are not uncommon. This study examined the clinical and radiographic outcomes of patients with AC joint dislocations repaired with the autogenous anterior half of the peroneus longus tendon (AHPLT) to achieve ACCR.

METHODS

Patients with a Rockwood type III to V AC joint dislocation and magnetic resonance imaging of the disruption of the CC ligaments, as well as the AC capsule, were prospectively recruited. Patients received ACCR using an autogenous AHPLT graft and were evaluated clinically and radiographically preoperatively and at 1, 3, 6, and 12 months postoperatively.

RESULTS

A total of 18 patients (mean age, 51 years) were prospectively recruited and received an autogenous AHPLT graft ACCR. Fifteen patients completed clinical and radiographic follow-up examinations at 12 months. The mean Constant score (CS) was 51 preoperatively and 93 at 12 months (P <.005). No significant difference was noted at 12 months between the CS of the injured and contralateral shoulder. The mean American Orthopedic Foot and Ankle Society score at 12 months was 99, and this was not different from the value at any other time point. Loss of reduction occurred in 10 patients (56%), and tunnel widening was observed in 9 (50%), but neither was significantly correlated with functional outcome.

CONCLUSION

Autogenous AHPLT appears to be a reliable tendon graft source for CC ligament reconstruction.

Truly anatomic coracoclavicular ligament reconstruction with 2 Endobutton devices for acute Rockwood type V acromioclavicular joint dislocations

BACKGROUND

Truly anatomic coracoclavicular ligament reconstruction (TACCR) according to the original insertions is a creative new method for the treatment of severe acromioclavicular separation. This research analyzed the clinical and radiologic results of TACCR in 25 patients with at least 2-year follow-up.

METHODS

The study enrolled 25 patients with Rockwood type V acromioclavicular joint dislocations who underwent TACCR using 2 Endobutton (Smith & Nephew Inc., Andover, MA, USA) devices from May 2013 to October 2015. Patients were assessed with clinical and radiologic follow-up at 3, 6, 12, 18, and 24 months postoperatively. The clinical assessments consisted of the visual analog scale and the Constant score. The radiographic evaluations were performed by measurements of the coracoclavicular distance.

RESULTS

The mean follow-up was 34 ± 6.8 months (range, 24-48 months). The visual analog scale and Constant scores revealed significant advancements from 5 ± 0.9 (range, 4-7) and 45 ± 5.6 (range, 30-54) scores preoperatively to 0 ± 0.5 (range, 0-2) and 95 ± 2.9 (range, 91-98) scores at 24 months postoperatively, respectively. The coracoclavicular distance significantly decreased from 23 ± 5.4 mm (range, 16-34 mm) preoperatively to 8 ± 0.9 mm (range, 7-10 mm) at the final follow-up.

CONCLUSIONS

TACCR represents a safe, reliable and creative surgical technique that yields good to excellent clinical and radiologic outcomes in the treatment of severe acromioclavicular separation.

Acromioclavicular and Coracoclavicular Ligament Reconstruction for Acromioclavicular Joint Instability: A Systematic Review of Clinical and Radiographic Outcomes

PURPOSE

To perform a systematic review of the available literature on clinical and radiographic outcomes after surgical treatment for acromioclavicular (AC) joint instability.

METHODS

A systematic review was performed according to PRISMA guidelines. Inclusion criteria were AC joint and coracoclavicular (CC) ligament reconstruction outcomes, English language, human studies, more than 10 patients in the study and a 2-year minimum follow-up. Exclusion criteria were animal studies, cadaveric studies, clinical studies without reported follow-up period or patient-reported outcomes, clinical studies of nonoperative treatment, AC reconstructions with concurrent lateral clavicle fracture, editorial articles, abstracts, presentations, reviews, case reports, and surveys.

RESULTS

The systematic review identified 34 studies (939 patients) after inclusion and exclusion criteria application. Postoperative American Shoulder and Elbow Surgeons (ASES) scores ranged from 93.8 to 96, 81.8 to 97.8, and 88.1 for free tendon graft, suspensory devices, and modified Weaver-Dunn techniques, respectively. Postoperative Constant scores were 76.4 to 96.0, 82.6 to 97.8, 85.9 to 97.0, 81 to 96 and 83.0 to 94.6 for free tendon graft, suspensory devices, synthetic ligament devices, modified Weaver-Dunn, and hook plate/K-wires techniques, respectively. All treatment modalities improved patient outcomes; however, hook plates and K-wires had the highest rate of complications (26.3%). Unplanned reoperation rates were 1.2%, 2.8%, 0.9%, 5.4%, and 2.6% in free tendon graft, suspensory devices, synthetic ligament devices, modified Weaver-Dunn, and hook plate/K-wires techniques, respectively.

CONCLUSIONS

Comparable subjective outcomes after surgical treatment of AC joint instability was reported for all modalities, with relatively low unplanned reoperation rates. Treatment with hook plate/K-wires was associated with the highest complication rates, and modified Weaver-Dunn had the highest unplanned reoperation rates. LEVEL OF EVIDENCE: Level IV, systematic review of Level I-IV studies.

A retrospective comparative study of arthroscopic fixation in acute Rockwood type IV acromioclavicular joint dislocation: single versus double paired Endobutton technique

Background

Rockwood type IV acromioclavicular joint (ACJ) dislocation is a trauma usually needs surgical treatment. Paired EndoButton technique (PET) is used in treating such condition. However, the effect of using different types of PET (single versus double PET) for fixation remains controversial. This study aims to evaluate and compare the efficacy of single and double PET and to provide a suitable option for the surgeons.

Methods

We retrospectively reviewed the charts of patients with acute Rockwood type IV ACJ dislocation who had undergone arthroscopic fixation using single or double PET fixation between March 2009 and March 2015. Seventy-eight consecutive patients identified from chart review were picked and were divided into the single and double PET group with 39 cases in each group. The indexes of visual analog scale score (VAS) for pain, the radiographs of the affected shoulder at different time points of the follow-up, the time of return to activities and sports, the constant functional score, and the Karlsson acromioclavicular joint (ACJ) score, were assessed in a minimum of 2 years postoperation.

Results

The average coracoclavicular (CC) and acromioclavicular (AC) distances of the affected joints in the double PET group were significantly smaller than those of the single PET group 2 years postoperation (P < 0.05). The average AC and CC distances in the healthy shoulder joints were significantly smaller than those of the affected joints in the single PET group (P < 0.05); however, these values were not significantly different from those of the affected joints in the double PET group (P > 0.05). The mean VAS pain score was not significantly different, while significant difference was found for the number and times of cases return to activities and sports, constant functional score, and Karlsson ACJ score (P < 0.05) between the two groups. Therefore, the double PET group has better outcome than the single PET group. Complications including redislocation, button slippage, erosion, or AC joint instability occurred in the single PET group, while the complication in the double PET group was rare.

Conclusions

Compared with the single PET, the double PET group achieved better outcome with less complications in arthroscopically treating acute Rockwood type IV ACJ dislocation.

Arthroscopic fixation of acute acromioclavicular joint disruption with TightRope™: Outcome and complications after minimum 2 (2-5) years follow-up

PURPOSE

To evaluate the midterm results of arthroscopic reconstruction of acute acromioclavicular (AC) joint disruption using TightRope™ system.

METHODS AND MATERIAL

We retrospectively assess the results of 24 patients of acute AC joint dislocation who were operated using TightRope system. Constant and University of California, Los Angeles (UCLA) scores and coracoclavicular distance were calculated pre- and postoperatively. Data was entered into MS excel and analyzed using the SPSS version 17.

RESULTS

The mean follow-up was 39.45 months. Constant and UCLA scores were significantly increased postoperatively. Six patients had partial loss of reduction within 3-6 months and two patients had a failure of construct. Constant score was significantly lower in these patients.

CONCLUSION

TightRope reconstruction of the AC joint is a reproducible and safe alternative to many other techniques of AC joint reconstruction. Early subluxation remains a concern and may reflect the need for technique modification.

Arthroscopically assisted reduction of acute acromioclavicular joint dislocation using a single double-button device: Medium-term clinical and radiological outcomes

INTRODUCTION

Double-button devices for endoscopic management of acute acromioclavicular joint dislocation (ACJD) provide satisfactory short-term functional and radiological results. However, little exists in the literature regarding the long- and medium-term results of these implants, especially regarding the evolution of the acromioclavicular joint (ACJ).

HYPOTHESIS

Satisfactory and steady long- and medium-term outcomes can be achieved in patients with acute ACJD undergoing endoscopically assisted ACJ repair using a single double-button device.

MATERIAL AND METHOD

A retrospective single-center study was conducted in patients with acute Rockwood III and IV ACJD treated endoscopically with a single double-button device from October 2008 to October 2010, allowing a minimum 5-year follow-up. Functional evaluation used Constant and Quick-DASH scores. Clinical evidence of dislocation recurrence was combined with bilateral Zanca views to assess coracoclavicular distance. Acromioclavicular osteoarthritis was evaluated on the Paxinos test and Zanca views.

RESULTS

Nineteen of the 25 operated patients were seen at a mean 76.9±8.5 months' follow-up. Mean age was 34.4±8.3 years. Mean Constant and Quick-DASH scores were 96.2±5.1 and 0.9±1.6 points, respectively. Four patients had a recurrence of their initial dislocation, 3 of whom had positive Paxinos test, whereas the 15 patients without recurrence had a negative test (p=0.004). Five patients had radiological evidence of ACJ osteoarthritis: all 4 patients with recurrence and 1 without (p=0.001).

CONCLUSION

Long- and medium-term radioclinical outcome of endoscopically assisted management of acute ACJD using a single double-button device seems to be satisfactory and steady over time. Recurrence of the initial dislocation appears to be related to onset of degenerative ACJ arthropathy.

LEVEL OF EVIDENCE

Therapeutic type IV-Retrospective case series.

New insights in the treatment of acromioclavicular separation

A direct force on the superior aspect of the shoulder may cause acromioclavicular (AC) dislocation or separation. Severe dislocations can lead to chronic impairment, especially in the athlete and high-demand manual laborer. The dislocation is classified according to Rockwood. Types I and II are treated nonoperatively, while types IV, V and VI are generally treated operatively. Controversy exists regarding the optimal treatment of type III dislocations in the high-demand patient. Recent evidence suggests that these should be treated nonoperatively initially. Classic surgical techniques were associated with high complication rates, including recurrent dislocations and hardware breakage. In recent years, many new techniques have been introduced in order to improve the outcomes. Arthroscopic reconstruction or repair techniques have promising short-term results. This article aims to provide a current concepts review on the treatment of AC dislocations with emphasis on recent developments.

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.

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.

Post-operative outcomes and complications of suspensory loop fixation device versus hook plate in acute unstable acromioclavicular joint dislocation: a systematic review and meta-analysis

BACKGROUND

Treatment of acute (≤3 weeks) acromioclavicular joint dislocation type III-VI is still controversial. Currently, the two modern techniques that are widely used are hook plate (HP) fixation and coracoclavicular ligament fixation using a suspensory loop device that consists of either a tightrope (single or double), endo-button (single or double), or synthetic ligament and absorbable polydioxansulfate sling.

MATERIALS AND METHODS

This systematic review was conducted according to the PRISMA guidelines. Relevant studies that reported Constant-Murley score (CMS), Pain Visual Analog score (VAS) and postoperative complications of either technique were identified from Medline and Scopus from inception to 5 October 2015.

RESULTS

Sixteen studies were included for the analysis of HP fixation, and 25 studies were included for analysis of loop suspensory fixation (LSF). Pooling of mean CMS and VAS scores gave 90.35 (95% CI 87.16, 93.54), 1.51 (95% CI 0.73, 2) in the HP group, and 92.48 (95% CI 90.91, 94.05), 0.32 (95% CI 0, 0.64) in the suspensory loop devices group, respectively. The pooled unstandardized mean differences (UMD) scores of CMS and VAS in LSF were 2.13 (95% CI -1.43, 5.69) and -1.19 (95% CI -2.03, -0.35) when compared to hook plating. The pooled prevalence of LSF and hook plating were 0.08 (95% CI 0.06, 0.10) and 0.05 (95% CI 0.02, 0.08) scores. The chance of having complications in the LSF group was 1.69 (95% CI 1.07, 2.60), which was statistically significantly higher than in the HP group.

CONCLUSION

LSF have higher shoulder function scores (CMS) and lower postoperative pain when compared to HP fixation; however, there are higher complication rates with LSF when compared to hook plating.

LEVEL OF EVIDENCE

IV.

Axial-Plane Biomechanical Evaluation of 2 Suspensory Cortical Button Fixation Constructs for Acromioclavicular Joint Reconstruction

BACKGROUND

Although numerous suture-button fixation techniques for acromioclavicular (AC) joint reconstruction have been validated with biomechanical testing in the superior direction, clinical reports continue to demonstrate high rates of construct slippage and breakage.

PURPOSE

To compare the stability of a novel closed-loop double Endobutton construct with a commercially available cortical button system in both the axial and superior directions.

STUDY DESIGN

Controlled laboratory study.

METHODS

Six matched pairs of fresh-frozen cadaveric upper extremities were anatomically dissected and prepared to simulate a complete AC joint dislocation. One side of each pair was reconstructed with the double Endobutton (DE) construct and other side with the dog bone button (DB) construct. The specimens were then tested using a materials testing machine, determining initial superior and axial displacements with a preload, and then cyclically loaded in the axial direction with 70 N for 5000 cycles. Displacement was again measured with the same preloads at fixed cycle intervals. The specimens were then loaded superiorly to failure.

RESULTS

At 5000 cycles, the mean axial displacement was 1.7 mm for the DB group and 1.2 mm for the DE group (P = .19), and the mean superior displacement was 1.1 mm for the DB group and 0.7 mm for the DE group (P = .32). Load at failure was similar (558 N for DE, 552 N for DB; P = .96). There was no statistically significant difference in the modes of failure.

CONCLUSION

Biomechanical testing of both constructs showed similar fixation stability after cyclical axial loading and similar loads to failure.

CLINICAL RELEVANCE

The strength of both constructs after cyclical loading in the axial plane and load-to-failure testing in the superior plane validate their continued clinical use for achieving stability in AC joint reconstruction procedures.

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.

Closed-Loop Double Endobutton Technique for Repair of Unstable Distal Clavicle Fractures

BACKGROUND

Displaced fractures of the distal clavicle are inherently unstable and lead to nonunion in a high percentage of cases. The optimal surgical management remains controversial.

HYPOTHESIS

Indirect osteosynthesis with a closed-loop double endobutton construct would result in reliable fracture union and obviate the need for additional surgery.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Eight patients with an acute unstable Neer type IIB distal clavicle fracture were treated with a closed-loop double endobutton implant. Mean follow-up averaged 3.4 years (range, 1-9 years). Two patients were lost to follow-up. The remaining 6 patients underwent a detailed functional and radiologic evaluation.

RESULTS

Definitive fracture healing was achieved in all patients. There were no complications, and no patients required additional surgery related to the index procedure. The mean Constant score was 97 at final follow-up.

CONCLUSION

The closed-loop double endobutton technique was reliable and effective in achieving fracture union in all patients with unstable Neer type IIB fractures of the distal clavicle. This technique obviates the need for late hardware removal that is often necessary when direct osteosynthesis is used and avoids potential complications associated with coracoclavicular cerclage constructs that require knot fixation.