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.

Acromioclavicular joint dislocation and concomitant labral lesions: a systematic review

Acromioclavicular (AC) joint dislocations frequently co-occur with intra-articular glenohumeral pathologies. Few comprehensive studies have focused on labral tears specifically associated with AC joint trauma. This systematic review will address this gap. A comprehensive electronic search was conducted across PubMed, Cochrane Library, and Google Scholar (pages 1-20) spanning from 1976 to May 19, 2023. Seven studies met the inclusion criteria for this systematic review, consisting of three retrospective studies and four case series. These studies collectively involved 1,044 patients, of whom 282 had concomitant labral lesions. The pooled prevalence of intra-articular labral injuries associated with acute AC joint dislocation was 27%. The prevalence of these labral lesions varied significantly between studies, ranging from 13.9% to 84.0% of patients, depending on the study and the grade of AC joint dislocation. Various types of labral tears were reported, with superior labrum anterior to posterior (SLAP) lesions being the most common. The prevalence of SLAP lesions ranged from 7.2% to 77.4%, with higher grades of AC joint dislocations often associated with a higher prevalence of SLAP tears. Moreover, grade V dislocations exhibited a complete correlation with SLAP tears. The studies yielded contradictory findings regarding older age and higher grades of AC joint dislocation as risk factors for concurrent labral lesions. This review underscores the frequent association between labral lesions and AC joint dislocations, particularly in cases of lower-grade injuries. Notably, SLAP lesions emerged as the predominant type of labral tear.

Surgical treatment for fracture of the medial end of the clavicle associated with ipsilateral acromioclavicular dislocation

The combination of an acromioclavicular joint dislocation and an ipsilateral medial end clavicle fracture is extremely rare. We report an acromioclavicular joint dislocation type IV associated with ipsilateral medial end clavicle fracture. The clavicular fracture was surgically treated with a locking plate and a non-operative treatment was conducted for the acromioclavicular joint dislocation. The results were clinically excellent for this 48-year-old, right-handed and sportive male patient at 3 months follow-up, with pain free full of range of motions and return to sports activities obtained.

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

PURPOSE

Acromioclavicular joint (ACJ) dislocations are usually graded radiographically according to Rockwood, but differentiation between Rockwood types III and V may be ambiguous. The potentially clinically relevant horizontal instability is barely addressed in coronal radiographs. It was hypothesized that a new radiologic parameter (V angle) would complement ACJ diagnostics on anteroposterior radiographs by differentiating between cases of Rockwood III and V while also considering the aspect of dynamic horizontal translation (DHT).

METHODS

Ninety-five patients with acute ACJ dislocations (Rockwood types III and V) were included retrospectively between 2017 and 2020. On anteroposterior views (weightbearing: n = 62, non-weight-bearing: n = 33), the coracoclavicular (CC) distance and the newly introduced V angle for assessing scapular orientation were measured bilaterally. This angle is referenced between the spinal column and a line crossing the superior scapular angle and the crossing point between the supraspinatus fossa and the medial base of the coracoid process, reported as the side-comparative difference (non-injured side *minus* injured side). DHT on Alexander views was divided into stable, partially unstable or completely unstable.

RESULTS

The V angle on the injured side alone (mean 50.0°; 95% confidence interval (CI), 48.6°-51.3°) showed no correlation with the side-comparative CC distance [%] (r = - 0.040; n.s.). Thus, the V angle on the non-injured side was considered, displaying a normal distribution (n.s.) with a mean of 58.0° (95% CI, 56.6°-59.4°). The side-comparative V angle showed a correlation with the side-comparative CC distance (r = 0.83; p < 0.001) and was able to differentiate between Rockwood types III (4.7°; 95% CI, 3.9°-5.5°; n = 39) and V (10.3°; 95% CI, 9.7°-11.0°; n = 56) (p < 0.001). A cut-off value of 7° had a 94.6% sensitivity and an 82.1% specificity (area under curve, AUC: 0.954; 95% CI, 0.915-0.994). The side-comparative V angle was greater for cases with complete DHT (8.7°; 95% CI, 7.9°-9.5°; n = 78) than for cases with partial DHT (4.8°; 95% CI, 3.3°-6.3°; n = 16) (p < 0.001). A cut-off value of 5° showed a sensitivity of 84.6% and a specificity of 66.7% (AUC 0.824; 95% CI, 0.725-0.924).

CONCLUSION

The scapular-based V angle on anteroposterior radiographs distinguishes between Rockwood types III and V as well as cases with partial or complete DHT.

STUDY DESIGN

Diagnostic study.

LEVEL OF EVIDENCE

Level II.

Rockwood type III is the most common type of acromioclavicular joint dislocation: A prospective cohort study investigating the incidence and epidemiology of acute acromioclavicular joint dislocations in an urban population

Introduction

Acromioclavicular (AC) joint dislocations are common, but basic epidemiological features and sub-classification are not well investigated. The aim of the study was to investigate the incidence and epidemiology of acute AC joint dislocations in the capital region of Denmark.

Methods

All patients with acute AC joint dislocation admitted to the emergency departments at 3 University Hospitals serving a population of 549,225 residents were prospectively registered from January to December 2019. Patients with trauma to the shoulder, pain from the AC joint and increased coracoclavicular distance on radiographs were included and classified according to Rockwood's classification. Data on age, sex and mechanism of injury were registered.

Results

A total of 106 patients, male:female ratio 8.6:1, were included. Rockwood type III was most common accounting for 59/106(55.7%) of the injuries. The incidence was 19.3 per 100,000 person-years at risk (PYRS). The age distribution was bimodal peaking at the ages of 20-24 and 55-59 years. The most common mechanism of injury was sports, 80/106, with cycling accounting for 51/106.

Discussion/Conclusion

Rockwood type III was the most common type of AC joint dislocation constituting 55.7% of the injuries. The incidence was 19.3 per 100,000 PYRS. Young and middle-aged males were at highest risk and most injuries occurred during sports.

Conservative treatment of Rockwood type III acromioclavicular joint separation: a randomized controlled trial sling vs. brace

Background

Management of Rockwood III acromioclavicular joint separations is a matter of ongoing debate, with nonoperative treatment being favored in recent literature. The aim of this study is to compare clinical and radiological outcomes of nonoperative treatment with a brace, which elicits a direct reduction force to the distal clavicle, to a sling. We hypothesized the brace might yield in better acromioclavicular joint (ACJ) reduction and cosmesis.

Methods

In this dual center prospective randomized controlled trial, all patients sustaining an acromioclavicular joint separation Rockwood III between July 2017 and August 2020 were included. Patients with previous ipsi- or contralateral ACJ injury or surgery were excluded. Randomization occurred in the emergency department to either the sling or brace group. Patients were followed up at 1, 6, and 12 weeks. Patient-reported outcome measures included subjective shoulder value (SSV) and American Shoulder and Elbow Surgeons (ASES) score at each follow-up and Constant Score at 6 and 12 weeks. Vertical distal clavicle displacement was assessed on bilateral non-weighted panoramic anteroposterior radiographs using coracoclavicular (CC) distance to calculate the CC-index.

Results

Thirty-five consecutive patients were included across the 2 sites, 18 (all male) in the brace and 17 (14 male) in the sling group. Baseline characteristics did not differ significantly between groups, the average age was 40 years, and body mass index 25.5 kg/m². Analysis revealed no statistical difference in CC-index between groups at the time of injury, 6 weeks and 12 weeks postinjury (P = .39, P = .11, and P = .21). SSV improved from 30 and 35 postinjury to 81 and 84 at 12 weeks in the sling and brace group, respectively (P = .59). ASES improved from 48 and 38 to 82 and 83, respectively (P = .84). Similarly, Constant Score improved from 64 and 67 to 82 and 81, respectively (P = .90). One patient in the brace group underwent ACJ stabilization with hamstring autograft at 4 months due to persistent pain.

Conclusion

This randomized controlled trial shows no statistically significant difference between the brace and sling group in clinical (SSV, ASES, Constant Score) or radiological (CC-index) outcomes after conservative treatment of Rockwood III injuries.

Ipsilateral Rockwood type IV acromioclavicular joint dislocation and midshaft clavicle fracture: a case report and review of the literature

The combination of ipsilateral acromioclavicular joint dislocation and midshaft clavicle fracture is rare. In the last 30 years, only 29 cases have been reported in literature. We present a case of a 55-year-old woman with this combined injury pattern on the right side after a fall from a bicycle. She underwent open reduction and plate fixation of the clavicle fracture and repair of both the acromioclavicular ligaments and the coracoclavicular joint with semi-rigid surgical implants. Six months of follow-up showed satisfactory results with full range of motion. In addition, we provide an overview of the literature regarding this rare injury pattern with treatment options and functional outcomes.

[Application of TightRope system combined with Locking-Loop biplane anatomical reconstruction technique for acute acromioclavicular joint dislocation]

Objective

To investigate the effectiveness of TightRope system combined with Locking-Loop biplane anatomical reconstruction technique in the treatment of acute acromioclavicular joint dislocation.

Methods

A clinical data of 28 patients with acute acromioclavicular joint dislocation who met the selection criteria and admitted between June 2018 and December 2021 was retrospectively analyzed. There were 18 males and 10 females, with an average age of 47.7 years (range, 22-72 years). The causes of injury included falling (13 cases) and traffic accidents (15 cases). The acromioclavicular joint dislocation was rated as Rockwood type Ⅲ in 7 cases, type Ⅳ in 16 cases, and type Ⅴ in 5 cases. The time from injury to operation was 4-13 days, with an average of 9.5 days. The acromioclavicular joint dislocation was reconstructed with TightRope system and high-strength wire by Locking-Loop methods during operation. The operation time and complications were recorded. Visual analogue scale (VAS) score, Constant-Murley score, and active range of motion of shoulder (forward flexion and upward lift, abduction and upward lift, and external rotation) were recorded before operation and at 12 months after operation to evaluate the functional recovery of shoulder. The loss of acromioclavicular joint reduction was assessed by comparing the coracoclavicular distance (CCD) based on the anteroposterior X-ray films at 3 days and 12 months after operation.

Results

The operation time was 58-100 minutes (median, 85 minutes). All incisions healed by first intention. All patients were followed up 12 months. During follow-up, 2 patients developed shoulder adhesion, which recovered after rehabilitation exercise. At 12 months after operation, the VAS score was significantly lower, the Constant-Murley score was significantly higher, and the range of motion of the shoulder joint (forward flexion and upward lift, abduction and upward lift, and external rotation) significantly increased when compared with preoperative ones ( P<0.05). X-ray films showed that the CCD was 8.4 (7.3, 9.4) and 9.2 (8.1, 10.1) mm at 3 days and 12 months after operation, respectively, with a significant difference ( Z=-4.665, P<0.001). During follow-up, there was no complication such as infection, titanium plate entrapment, fracture, internal fixation failure, or redislocation.

Conclusion

The treatment of acute acromioclavicular joint dislocation with TightRope system combined with Locking-Loop biplane anatomical reconstruction has the advantages of small incision, joint reduction under direct vision, high fixation strength, and low incidence of postoperative complications, which can effectively relieve the pain of patients' shoulder joint and facilitate the recovery of shoulder joint function.

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.

A Modified Endoscopic Technique with Three Incisions for Rockwood Types III and V Acromioclavicular Joint Dislocation

OBJECTIVE

Acromioclavicular joint dislocation is one of the most common shoulder injuries in young men. With the advancement of minimally invasive technology, arthroscopy of acromioclavicular joint dislocation has been recognized for its good curative effect. This study aimed to explore the technical details and clinical efficacy of a modified minimally invasive endoscopic treatment for acromioclavicular joint dislocation.

METHODS

Clinical data of patients receiving the three-incision endoscopic treatment were retrospectively reviewed between July 2013 and July 2019. A total of 72 patients with acromioclavicular joint dislocation of Rockwood type III (n = 42) and type V (n = 30) were included in this study. Postoperative routine radiography was performed to evaluate acromioclavicular joint reduction and fixation. In addition, functional recovery of the shoulder joint was assessed using the American Shoulder and Elbow Surgeons (ASES) and Constant-Murley scores. Differences between the preoperative and postoperative data were compared using paired t-tests.

RESULTS

All patients underwent loop plate elastic fixation under endoscopy during 24 to 48 months of follow-up. Postoperative radiography showed that the acromioclavicular joint achieved anatomical reduction. The ASES score (91.1 ± 4.2) was significantly improved compared to the preoperative ASES score (62.4 ± 3.1) (t = 46.65, P < 0.0001). The Constant-Murley score (93.1 ± 4.6) was also significantly higher than that before the operation (40.7 ± 6.4) (t = 56.41, P < 0.0001). No postoperative complications occurred. During follow-up, four patients had mild acromioclavicular joint degeneration but no obvious pain symptoms.

CONCLUSION

The modified three-incision endoscopic technique optimizes the surgical incision, reduces trauma, is minimally invasive, and provides rapid rehabilitation with satisfactory clinical outcomes.

Comparison of Hook Plate Alone, Hook Plate Augmented with Suture Anchor, and Arthroscopically-assisted TightRope Fixation in the Treatment of Patients with Acute Type V Acromioclavicular Joint Dislocations

INTRODUCTION

The best treatment for Rockwood type V acromioclavicular (AC) joint dislocation is unknown.

HYPOTHESIS

Hook plate augmented with suture anchor (HA) may have different clinical and radiological results than hook plate alone (H), and arthroscopically assisted TightRope (TR) techniques in treating acute type V AC joint dislocations.

MATERIAL AND METHODS

This retrospective study included 71 patients with acute type V AC joint dislocations between December 2010 and August 2018. Patients were categorized into three groups: H group (n =22), HA group (n =23) and TR group (n =26). We measured the coracoclavicular distance (CCD) differences and CCD ratio compared to uninjured side pre-operatively, immediately post-operatively, at 3-month and 2-year after operation. Clinical outcomes were assessed as well at the same time points. Loss of correction was determined by the CCD difference and ratio between surgical and uninjured sides.

RESULTS

The mean age and follow-up period were 41.8±24.7 years and 30.2±4.3 months, respectively. No significant differences were found in the demographic data between the three groups. The HA group presented a trend of less overcorrection but without significance compared with the H group at immediately post-operation, 3-month, and 2-year follow-up. (CCD difference: -2.4mm vs. -3.7mm, -1.6mm vs. -1.8, and 0.2mm vs -1.9mm, CCD ratio: 67.7% vs. 40.9%, 79.3% vs. 70.1%, and 100.6% vs. 86.5%, respectively). The HA group also had significantly less loss of correction compared with the TR group at 3-month and 2-year after the operation (CCD difference: -1.6mm vs. 1.6mm, 0.2mm vs. 2.4mm; CCD ratio: 79.3% vs. 122.2%, 100.6% vs. 136.1%, all p<0.05). All three methods achieved significant improvement in function and pain without inter-group differences. No coracoid-related or tunnel complications occurred.

DISCUSSION

The hook plate alone, and hook plate with suture anchor augmentation techniques provided less residual vertical instability compared to TightRope fixation at 2-year follow-up. The patient-reported functional outcomes were promising and comparable among the three groups.

LEVEL OF EVIDENCE

III, Retrospective comparative therapeutic trial.

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.

Surgical treatments for acute unstable acromioclavicular joint dislocations

INTRODUCTION

Surgical treatment is usually recommended for acute, high-grade acromioclavicular joint (ACJ) injuries. A wide variety of surgical techniques exist, and the literature does not strongly support one over the other. In this literature review, we describe and compare the results of different surgical treatments for the management of acute unstable ACJ dislocation and aim to guide surgeons on optimal treatment.

MATERIALS AND METHODS

A literature review was performed by searching PubMed, Medline, Cochrane, and Embase databases. Seventeen studies met the inclusion criteria and were analyzed. Only studies with comparative data were included. The clinical and radiological outcomes of these studies were reviewed.

RESULTS

Seventeen studies were included in this literature review. We found no difference in outcomes between open and arthroscopic procedures. Coracoclavicular ligament (CCL) reconstruction techniques provide better results than the more rigid hook plate fixation. There is no evidence that biologic repair with tendon graft is superior to synthetic grafts. Furthermore, an autograft is not shown to be better than an allograft. Rigid fixation between the clavicle and coracoid and the non-anatomic Weaver-Dunn technique appears less popular in recent literature. The hook plate is associated with subacromial osteolysis, acromial erosion, and the morbidity of a secondary procedure.

DISCUSSION

There is a recent increase in publications on the reconstruction of the ACJ after injury, with new techniques focusing on the anatomic reconstruction of the CCLs aiming to restore both vertical and horizontal plane stability of the ACJ using synthetic/biological grafts. Despite the plethora of new techniques introduced, meaningful comparisons are difficult to draw due to the heterogeneity of the treatments used and the outcome measure used to assess the results.

Clinical Outcomes of Arthroscopy-Assisted Modified Triple Endobutton Plate Fixation in Rockwood Type III Acute Acromioclavicular Joint Dislocation: A Retrospective Study

Objective

The common triple Endobutton plate (CTEP) fixation is a lengthy procedure that is associated with high failure rates. Therefore, we used arthroscopy to improve the Endobutton fixation method by shortening the duration of surgery and reducing operative complications. This study explored the safety and effectiveness of arthroscopy‐assisted modified triple Endobutton plate (MTEP) fixation in Rockwood type III managing acute acromioclavicular joint (ACJ) dislocation.

Methods

This was a retrospective single‐center study involving 73 patients with Rockwood type III acute ACJ dislocation treated between January 2016 and January 2021. The 73 patients were classified into three groups, the acromioclavicular hook plate (ACHP) group (22 cases), CTEP group (24 cases) and MTEP group (27 cases), based on the type of surgical treatment they received. Clinical outcome data from the patient records, including the Constant–Murley score (CMS), American Shoulder and Elbow Surgeons score (ASES) and University of California at Los Angeles shoulder rating scale score (UCLA), were retrospectively reviewed. The scores were assessed before surgery and at the third and twelfth month after surgery. The clavicle‐coracoid (CC) distance on the affected side was estimated from imaging scans taken before surgery, on the second day after surgery, and within the third and twelfth month after surgery. The student's t‐test was used to compare normally distributed data for independent samples, while homogeneity of variance test was used to compare normally distributed data among multiple groups. Non‐normally distributed data were compared using Mann–Whitney rank‐sum tests.

Results

There were no differences in age, gender, body mass index (BMI), dislocated side, trauma etiology, and duration of follow‐up among the three groups. There was also no significant difference in the duration of surgery between the ACHP and MTEP groups, although the duration in the two groups was shorter than in the CTEP group (P < 0.05). The duration of hospitalization for the MTEP group was significantly shorter than for the CTEP group which was in turn shorter than for the ACHP group (both P < 0.05). There was no significant difference in postoperative CMS, ASES, and UCLA scores between the CTEP and MTEP groups but the score for the two groups differed significantly from those of the ACHP group (all Ps < 0.05). In addition, there was no significant difference in CC distance among the three groups after surgery (P > 0.05).

Conclusion

Arthroscopic reconstruction of the coracoclavicular ligament using MTEP fixation to manage acute Rockwood type III ACJ dislocation is minimally invasive, and is associated with rapid functional recovery, few complications and satisfactory early clinical results.

High Early-onset acromioclavicular secondary pathologies after acute arthroscopic joint reduction: a cohort study

PURPOSE

The research aim was to determine the prevalence and risk factors of early secondary acromioclavicular (AC) joint disease in patients undergoing acute arthroscopic AC joint reduction and fixation and early complications of acute surgical treatment in patients with high-grade AC joint dislocation.

METHODS

Overall, 102 patients diagnosed with Rockwood type V AC joint dislocation and undergoing arthroscopic coracoclavicular fixation were included. Early clinical and radiological complications were evaluated, as well as risk factors of secondary AC joint pathology.

RESULTS

Twenty-nine patients (28%) presented with a secondary AC joint pathology, with 24 and 5 cases of osteolysis and osteoarthritis, respectively. The main complication was a loss of reduction of ≥ 1 mm (78%). Patients aged > 55 years were more likely to develop a secondary AC joint disease (odds ratios (OR) = 10.1, 95% confidence interval (CI): 1.42 - 72.55, p = 0.021). Patients with osteolysis (OR = 3.2, 95% CI 1.16 - 9.27, p = 0.025) or loss of reduction of > 5 mm (OR = 7.4, 95% CI 2.31 - 24.08, p = 0.001) were more likely to develop AC joint pain. Patients with an initial over-reduction were less likely to develop a subluxated AC joint (OR = 0.033, 95% CI 0.0021-0.134, p = 0.001) CONCLUSION: Age > 55 years and female sex were identified as risk factors of early-onset secondary AC joint disease. Osteolysis and a loss of reduction of > 5 mm were risk factors of AC joint pain but not of revision surgery. The main early complication was a loss of reduction of ≥ 1 mm. An initial over-reduction of the distal clavicle was a protective factor to avoid AC joint subluxation.

No difference in clinical outcome at 2-year follow-up in patients with type III and V acromioclavicular joint dislocation treated with hook plate or physiotherapy: a randomized controlled trial

BACKGROUND

The need for operative treatment of acute acromioclavicular (AC) joint dislocation is unclear. The purpose of this randomized controlled trial was to compare the outcomes after operative treatment with a hook plate with the outcomes after nonoperative treatment of acute Rockwood type III and type V AC joint dislocations separately.

METHODS

The inclusion criteria were patients aged 18-65 years with an acute type III or type V AC joint dislocation with the availability to start treatment within 3 weeks after trauma. All patients received the same standardized outpatient rehabilitation protocol and were followed up for 24 months. Assessments were based on radiographs, clinical examination findings, and questionnaires. The primary outcome was the Constant score (CS). The secondary outcomes were as follows: Subjective Shoulder Value (SSV), QuickDASH score (abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire), shoulder pain at rest and during movement rated using a visual analog scale, EQ-5D (European Quality of Life 5 Dimensions) score, patient satisfaction, cosmesis, complications, and adverse events. The 4 groups were compared using 1-way analysis of variance and intention to treat.

RESULTS

The included patients (N = 124) (mean age, 40 years [range, 18-64 years]; 91% male patients) were randomized, stratified by type, to nonoperative treatment (type III, n = 33; type V, n = 30) or operative treatment with a hook plate (type III, n = 30; type V, n = 31) at a single center. Three patients randomized to physiotherapy dropped out before any follow-up measures, leaving 121 patients in the study. Complete clinical follow-up data were obtained from 118 patients at 24 months. At 3 months, patients in both nonoperatively treated groups had a significantly better mean CS, SSV, and QuickDASH score and had less pain at rest and during movement compared with patients treated operatively. At 6, 12, and 24 months, there were no significant differences in the CS, SSV, QuickDASH score, pain, or EQ-5D score between the groups regardless of intervention. At 24 months, the mean CS was 88 for nonoperatively treated type III patients vs. 91 for operatively treated type III patients and was 90 vs. 91 for type V patients (P = .477). At final follow-up, patients had regained 97% of the mean CS comparing the uninjured and injured shoulders and 86% of the patients rated the result as excellent or good. Eleven patients assigned to nonoperative treatment (18%, 6 type III and 5 type V) underwent surgery within 19 months.

CONCLUSIONS

Both the nonoperative and operative treatment groups had very good restoration of shoulder function and patient satisfaction at 24 months, and operative treatment did not lead to better outcomes compared with nonoperative treatment. In conclusion, our study does not support surgery with a hook plate in patients with acute Rockwood type III or type V AC joint dislocations.

[Analysis of the effect of double button plate combined with strengthened anchor in the treatment of acromioclavicular dislocation]

OBJECTIVE

To evaluate the efficacy and prognosis of double button plate combined with strengthened anchor technique and clavicular hook plate internal fixation for complete acromioclavicular joint dislocation.

METHODS

From July 2017 to September 2020, a total of 42 patients with acromioclavicular joint dislocation treated by surgery were choosen as study objects and divided into observation group (21 cases) and control group (21 cases). In the observation group, there were 14 males and 7 females, aged 21 to 63 years old, with an average of (45.05±8.70) years old. In the control group, there were 16 males and 5 females, aged 25 to 68 years old, with an average of(45.00±9.44) years old. The patients in the observation group were treated with double button plate combined with strengthened anchor technique, whereas those in the control group received clavicular hook plate internal fixation. The two groups were compared in terms of operating time, intraoperative blood loss, postoperative hospital stay, shoulder pain(visual analogue scale, VAS) score, shoulder function Constant-Murley score and postoperative complications.

RESULTS

There was no significant difference between the two groups in intraoperative blood loss or postoperative hospital stay(P>0.05). The operating time of double button plate combined with strengthened anchor technique group (65.24±5.36) min was significantly longer than that of the clavicular hook plate group (48.81±4.72) min, and the difference was statistically significant (P<0.05). There was no significant difference in shoulder function or pain degree between the two groups before operation (P>0.05). After 1 month, 3 months and 6 months, the Constant-Murley score of the observation group was 73.29±2.15, 85.43±1.47, 93.86±1.24 separately, which were significantly higher than those of the control group;and the VAS score was 2.76±0.62, 1.71±0.64, 0.57±0.51 separately, which were significantly lower than those of the control group (P<0.05). One instance of shoulder discomfort was found in the observation group, while 5 cases of shoulder pain, 2 cases of restricted shoulder mobility, and 1 case of subacromial bone absorption were found in the control group. In both group, there was no loss of reduction.

CONCLUSION

In the treatment of complete acromioclavicular joint dislocation double button plate combined with strengthened anchor technique achieves favorable clinical result. Internal fixation does not need to be removed. The recovery of shoulder joint function and pain relief are superior than clavicular hook plate internal fixation, which is more worthy of clinical promotion.

Acromioclavicular joint instability on cross-body adduction view: the biomechanical effect of acromioclavicular and coracoclavicular ligaments sectioning

Background

The acromioclavicular (AC) and coracoclavicular (CC) ligaments are important stabilizers of the AC joint. We hypothesized that AC and trapezoid ligament injuries induce AC joint instability and that the clavicle can override the acromion on cross-body adduction view even in the absence of conoid ligament injury. Accordingly, we investigated how sectioning the AC and CC ligaments contribute to AC joint instability in the cross-body adduction position.

Methods

Six fresh-frozen cadaveric shoulders were used in this study, comprising five male and one female specimen, with a mean age of 68.7 (range, 51–87) years. The left side of the trunk and upper limb, and the cervical and thoracic vertebrae and sternum were firmly fixed with an external fixator. The displacement of the distal end of the clavicle relative to the acromion was measured using an electromagnetic tracking device. We simulated AC joint dislocation by the sequential resection of the AC ligament, AC joint capsule, and CC ligaments in the following order of stages. Stage 0: Intact AC and CC ligaments and acromioclavicular joint capsule; stage 1: Completely sectioned AC ligament, capsule and joint disc; stage 2: Sectioned trapezoid ligament; and stage 3: Sectioned conoid ligament. The superior clavicle displacement related to the acromion was measured in the horizontal adduction position, and clavicle overriding on the acromion was assessed radiologically at each stage. Data were analyzed using a one-way analysis of variance and post-hoc tests.

Results

Superior displacement was 0.3 mm at stage 1, 6.5 mm at stage 2, and 10.7 mm at stage 3. On the cross-body adduction view, there was no distal clavicle overriding at stages 0 and 1, and distal clavicle overriding was observed in five cases (5/6: 83%) at stage 2 and in six cases (6/6: 100%) at stage 3.

Conclusion

We found that AC and trapezoid ligament sectioning induced AC joint instability and that the clavicle could override the acromion on cross-body adduction view regardless of conoid ligament sectioning. The traumatic sections of the AC and trapezoid ligament may lead to high grade AC joint instability, and the distal clavicle may subsequently override the acromion.

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).

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.

Arthroscopic Anatomical Acromioclavicular Joint Reconstruction using a Button Device and a Semitendinosus Graft

Objective

To report a new technique for anatomical acromioclavicular (AC) joint reconstruction.

Methods

In order to minimize such complications, the authors describe a new anatomical and biological AC joint repair. This technique aims to provide greater stability by using two anatomically placed clavicular tunnels and a combined construct with a double endobutton cortical fixation for primary stabilization, and to be biologically advantageous by using an autologous semitendinosus (ST) tendon graft. Additionally, the coracoclavicular ligament reconstruction is complemented with an AC joint cerclage and capsular reinforcement, which will protect the biological construction in its initial stage of healing.

Results

This technique provides adequate primary and secondary biomechanical stability by passing both a semitendinosus autogenous graft and a double endobutton device, through anatomically placed and small diameter clavicle holes, without the need for coracoid drilling. Our technique showed encouraging results regarding pain resolution, range of motion, and function. At final follow‐up we experienced excellent results with average pain score of 1.6, and average ROM of 159° of forward flexion, 160° of abduction, 68° of external rotation, and internal rotation level at T11. Postoperative function also showed great improvements with average ASES of 85 points, an average Constant Score of 87 and a Subjective Shoulder Value of 89 points. This technique also achieved perfectly acceptable radiographic results, with an average coracoclavicular distance increase of 0.8 mm. Regarding complications, our sample showed one case of AC join subluxation, two cases of internal saphenous nerve injury, and two partial graft tears at the suture‐button interface, with none of these requiring surgical revision.

Conclusion

This technique is advantageous in treatment of acromioclavicular joint dislocation and can be performed in both the subacute and chronic setting.

Effect of subacromial erosion shape on rotator cuff and clinical outcomes after hook plate fixation in type 5 acromioclavicular joint dislocations: a retrospective cohort study

Background

Surgical fixation using hook plates is widely used in the treatment of acromioclavicular (AC) joint dislocations. The purpose of this study was to evaluate the incidence and shape of subacromial erosions after removal of the hook plate in type 5 AC joint dislocations. Further, we evaluated the effect of the shape of the subacromial erosion on the rotator cuff.

Methods

We retrospectively reviewed 30 patients who underwent hook plate fixation for type 5 AC joint dislocations at our hospital between December 2010 and December 2018. Patients with a follow-up of at least 1 year were included. Clinical outcomes were assessed using the final follow-up Constant-Murley, Korean Shoulder, and visual analog scores. To ensure that the appropriate reduction was well maintained, the coracoclavicular distances of the injured and contralateral sides were evaluated at the last follow-up. Computed tomography was performed to investigate the presence and shape of the subacromial erosion after hook plate removal at 4 months after surgery. Ultrasonography was performed to investigate the presence of rotator cuff lesions at the last follow-up. Clinical and radiological outcomes were compared between groups divided according to the presence and types of subacromial erosions.

Results

Subacromial erosion was observed in 60% of patients (18/30): 13, 2, and 3 simple groove, cave, and marginal protrusion types, respectively. Four patients showed reduction loss at the final follow-up. There were no significant differences in clinical and radiological outcomes between the groups with and without subacromial erosion. Moreover, there were no significant differences between groups according to the types of subacromial erosion. There were no rotator cuff lesions, such as partial tears, in the injured shoulders.

Conclusions

Hook plate fixation may induce subacromial erosions. However, the subacromial erosions caused by the hook plate did not affect the clinical outcomes of type 5 AC joint dislocations. Moreover, regardless of its shape, the subacromial erosion did not affect the clinical outcomes nor cause rotator cuff lesions after plate removal.

A modified single-endobutton technique combined with nice knot for treatment of Rockwood type III or V acromioclavicular joint dislocation

PURPOSE

Double-endobutton technique, as a widely accepted strategy for the treatment of acromioclavicular joint dislocation, is undergoing constant improvement. This study aims to assess the clinical effect of a modified single-endobutton combined with the nice knot in the fixation of Rockwood type III or V acromioclavicular joint dislocation.

METHODS

From January 2016 to June 2019, 16 adult patients (13 males and 3 females) with Rockwood type III or V acromioclavicular joint dislocation were treated with a modified single-endobutton technique combined with the nice knot in our department. The age ranged from 18 to 64 years old with an average of 32.8 years old. Operative time, intraoperative blood loss, post-operative clinical outcomes and radiographic results were recorded and analyzed. Preoperative and last follow-up scores in the Constant-Murley Scale, Neer score, Rating Scale of the American Shoulder and Elbow Surgeons and VAS scale and complications such as infection, re-dislocation, implant loosening, medical origin fracture and hardware pain were recorded and evaluated.

RESULTS

Sixteen patients were followed up for 6 to 18 months with an average of 10.3 months. The operative time was 50-90 min with an average of (62.5 ± 3.10) min. The intraoperative blood loss was 30-100 ml, with an average of (55.0 ± 4.28) ml. The complications, such as wound infection, internal fixation failure and fractures, were not found in these cases. According to Karlsson criteria, there were excellent in 14 cases, good in 2 cases at the final follow-up. The mean VAS score of the patients was 5.88 ± 0.26 preoperatively, compared with 0.19 ± 0.14 at the final follow-up evaluation. The difference was statistically significant (P < 0.05). The mean Constant score was 45.5 ± 2.0 preoperatively, compared to 94.0 ± 0.73 at the final follow-up evaluation. The difference was statistically significant (P < 0.05). Patients had statistically significant preoperative and postoperative AC (acromioclavicular distance) and CC (coracoclavicular distance) distances (P < 0.05); 6 months postoperatively the AC(P = 0.412) and CC(P = 0.324) distances were not statistically significant compared to the healthy side.

CONCLUSION

Nice knot provides a reliable fixation for the single-endobutton technique in the treatment of acromioclavicular dislocations. The modified single-endobutton technique combined with the nice knot can achieve good clinical outcomes in the treatment of Rockwood type III or V acromioclavicular joint dislocation.

Efficacy of Transosseous Tunnel Placement for Triple Endobutton Plate in Acromioclavicular Joint Reconstruction: A Three-Dimensional Printing Guide Design Technology

Objective

Explore an accurate transosseous tunnel drilling method based on three‐dimensional (3D) printing technology for acromioclavicular joint reconstruction (ACD), design a guide design, and evaluate its accuracy.

Methods

Using Mimics software to reconstruct 100 cases of acromioclavicular joint computed tomography (CT) data. In design 2, the non‐collinear tunnel is superimposed on the 3D model, and a virtual drilling is performed between the clavicle and the coracoid using a triple inner gusset. Then, in the Geomagic Studio software model, an elliptical plane is calculated and extracted as a guide design for precise drilling. Then put the design and the 3D shoulder model together for 3D printing. Ten lengths were measured, and the effects of the virtual model, the actual model, and the guide rail design were compared.

Results

We successfully compared 10 parameters of 3D virtual model and actual model. There was no significant difference between actual and virtual bone tunnels in 10 measurements (P > 0.05).

Conclusions

The accuracy of ACD combined with 3D printing guidance design technology in the transosseous tunnel of adult shoulder is reliable.

Os acromiale may be a contraindication of the clavicle hook plate: case reports and literature review

Background

Os acromiale can be potentially missed or misdiagnosed as acromion fracture, and this can affect treatment determination if it is complicated with an ipsilateral shoulder injury. The clavicle hook plate is a widely used technique for distal clavicle injuries, leading to transacromial erosion, particularly when in the presence of os acromiale.

Case presentation

A 70-year-old man and a 78-year-old man who had limited mobility and severe pain in their right shoulders following falls attended the emergency center. Both patients were diagnosed with os acromiale with CT or MRI and acute distal clavicle fracture or acromioclavicular joint dislocation. Following a comprehensive evaluation, os acromiale may limit the application of a clavicle hook plate due to potential transacromial erosion. The distal clavicle fracture with ipsilateral os acromiale received treatment with a volar radius locking T plate, and the acromioclavicular joint dislocation with ipsilateral os acromiale was reconstructed using suture anchors. Both yielded satisfactory outcomes and voided transacromial erosion.

Conclusions

Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate. An axillary lateral radiograph is recommended to detect potential os acromiale in patients using a hook plate.

Biomechanical testing of three coracoclavicular ligament reconstruction techniques with a 3D printing navigation template for clavicle-coracoid drilling

Background

The identification and precise clavicle-coracoid drilling during coracoclavicular (CC) ligament reconstruction for acromioclavicular (AC) joint dislocation require a high level of experience and surgical skills. Furthermore, the improvement of flexible fixation, such as Endobutton techniques for CC ligament reconstructions is ongoing. We have developed a 3D printing technique navigation template for clavicle-coracoid drilling and a novel implant for the reconstruction. This study aimed to determine the efficiency of the navigation template for clavicle-coracoid drilling and to evaluate the biomechanical performance of the novel CC ligament reconstruction technique.

Methods

A total of 24 fresh-frozen human cadaveric shoulders were randomly assigned to 1 of 3 reconstruction groups or a control group: TightRope, Triple Endobutton, and the Adjustable Closed-Loop Double Endobutton technique. Computed tomography scans, navigation template designs, and 3D printing were performed for the shoulders. Then, AC joint dislocation was simulated in the reconstruction groups, and 3 CC ligament reconstruction techniques were operated via the 3D printing template separately. Furthermore, biomechanical protocols including the translation test (load from 5 to 70 N) and the load-to-failure test were performed to characterize the behaviors and strengths. One-way ANOVA test analyzed differences in displacement under the translation load and the load at failure.

Results

CC ligament reconstructions were performed successfully along with the 3D printing navigation template in the 3 reconstruction groups. During the translation test, no significant difference was found in displacements among the 4 groups. Meanwhile, the mean load of all reconstruction groups at failure (Adjustable Closed-Loop Double Endobutton, 722.1620 N; TightRope, 680.4020 N; Triple Endobutton, 868.5762 N) was significantly larger than the control group (564.6264 N, P<0.05). The Triple Endobutton group had the maximum load at failure (P<0.05), however, no significant difference was noticed between the other 2 reconstruction groups (P>0.05).

Conclusions

The 3D printing navigation template may become helpful and reliable for AC joint dislocation surgery. Among the 3 CC ligament reconstruction techniques, the Triple Endobutton technique has the best strength in terms of biomechanics, while the biomechanical strength of the Adjustable Closed-Loop Double Endobutton technique is reliable in comparison with the TightRope technique.

Surgery improves the clinical and radiological outcome in Rockwood type IV dislocations, whereas Rockwood type III dislocations benefit from conservative treatment

PURPOSE

Despite the available classifications, diagnostics and treatment of acute acromioclavicular joint (ACJ) injuries are still vague and challenging for trauma and shoulder surgeons. This study aimed to evaluate the dynamic radiographic as well as clinical outcome of operatively and conservatively treated Rockwood (RW) type III and IV ACJ dislocations.

MATERIALS AND METHODS

All patients with RW type III and IV ACJ dislocations between 2009 and 2016 (n = 226) were included in this retrospective data analysis with a prospective follow-up examination. According to their injury classification, patients were subdivided in an operative and conservative treatment group. Examiner blinded clinical evaluation including the constant score (CS), American shoulder and elbow surgery (ASES) score, the acromioclavicular joint instability (ACJI) score, visual analog scale (VAS), bilateral force measurements, and posttraumatic/postsurgical sequelae were assessed. Fluoroscopic evaluations including dynamic stability assessment with functional axillary views were performed for every patient.

RESULTS

For follow-up examination (mean 4.8 years ± 0.3 SEM) 56 patients (29 RW type III, 27 RW type IV) were available. In patients with RW type III ACJ dislocations [operative (n = 10); conservative (n = 19)] prolonged duration of treatment was seen in operatively treated patients (p < 0.05). Clear improvement could be shown for the ACJI score (p < 0.05) and coracoclavicular (CC) and acromioclavicular (AC) distance (p < 0.05) in the operative group. In patients with RW type IV ACJ dislocations [operative (n = 18); conservative (n = 9)] superior clinical results were found in operated patients with highly significant differences for the ACJI score (p < 0.001). Radiographic dynamic horizontal analysis showed nearly normalized anteroposterior translation in operated patients (p < 0.05). No differences were found regarding arthroscopic or open procedures.

CONCLUSION

Accurate diagnostics including sufficient dynamic stability assessment with functional axillary views are strongly advised for patients with ACJ dislocations. Conservative treatment should be recommended for patients with RW type III ACJ dislocations, due to shorter duration of treatment with good clinical results but lacking operative risks. In patients with RW type IV ACJ dislocations, surgical treatment is recommended because of superior clinical and radiological results.

LEVEL OF EVIDENCE

Level III.

Long-term stability of coracoclavicular suture fixation for acute acromioclavicular joint separation

PURPOSE

The optimal (SBJI) surgical treatment for acute acromioclavicular (AC) joint disruption remains controversial. What is being presented is the long-term functional outcomes of a double cross-looped coracoclavicular (CC) suture technique with the intention of restoring both anteroposterior and superior displacement of the clavicle.

METHODS

Between 2007 and 2016, 81 patients underwent surgical reconstruction for acute acromioclavicular joint (AC) disruption in two orthopaedic centers. Two patients died for reasons unrelated to the treatment, and seven missed the final follow-up appointment, leaving 72 patients (67 males; 5 females; age 37 ± 12.4; range 15-64 years) for clinical and radiological assessments. All cases were classified according to the Rockwood classification as type III (n = 34), IV (n = 14) or V (n = 24). The dislocation was repaired with double cross-looped CC fixation using four Ethibond sutures passing underneath the coracoid and through a 4.5 mm drill hole in the clavicle in opposing directions to control both anteroposterior and vertical displacement. Radiological investigation preoperatively and at the last follow-up included anteroposterior and/or Zanca views, axillary or Alexander views, and comparative stress radiography of both AC joints. Patients were evaluated clinically with the Constant-Murley score (CMS) and Acromio Clavicular Joint Instability Score (ACJIS). Loss of reduction, subluxation, CC ligament ossification, post-traumatic arthritis, and peri-implant fractures were also recorded.

RESULTS

Seventy-two patients were available for the last clinical and radiological evaluations. At a median follow-up period of 6.3 ± 2.1 years (range 3-12 years), the CMS and ACJIS were 92.1 ± 7.2 (range 60-100 points) and 90.4 ± 8.6 (range 45-100 points), respectively. Complications included 9 (12.5%) patients with slight loss of reduction, 2 (1.7%) with dislocation recurrence, 1 (1.3%) with superficial infection, 1 (1.3%) with a fracture of the lateral end of the clavicle, and 2 (1.7%) with persistent tenderness in the AC joint. The incidence of periarticular ossification was 22.4% and did not affect the final outcome.

CONCLUSIONS

This technique represents an effective and low-cost treatment for acute AC joint separations.

LEVEL OF EVIDENCE

IV.

Biomechanical analysis of a novel clavicular hook plate for the treatment of acromioclavicular joint dislocation: A finite element analysis

BACKGROUND

Clavicular hook plates are frequently used in clinical orthopedics to treat acromioclavicular joint dislocation. However, patients often exhibit acromial osteolysis and peri-implant fracture after hook plate fixation. To solve the above problems, we developed a novel double-hook clavicular plate and used finite element analysis (FEA) to investigate its biomechanical properties.

METHODS

A finite element (FE) model was constructed and validated. Then, a double-hook clavicular plate, a single-hook clavicular plate, and an anatomical double-hook clavicular plate was implanted into the acromioclavicular joint and fixed with screws in groups 1, 2 and 3, respectively. Finally, a load was applied, and some indicators were recorded and analyzed.

RESULTS

For both the proximal clavicular rotation angle and the distal clavicular displacement, the range of motion in groups 1 and 3 was more than 90% lower than that in group 2. The maximum von Mises stress of the clavicle in groups 1 and 3 was more than 45% lower than that in group 2. The maximum stress of the acromion in group 2 was significantly higher than that in groups 1 and 3, and that in group 3 was less than that in group 1, for both cortical and cancellous bone.

CONCLUSIONS

The double-hook clavicular plate could immediately reconstruct the stability of the acromioclavicular joint, effectively reducing the stress of the bone around the clavicle and screws. Additionally, the double-hook clavicular plate could reduce the peak stress of the acromion and produce a more uniform stress distribution.

Comparison of the Radiological and Functional Results of Tight Rope and Clavicular Hook Plate Technique in the Treatment of Acute Acromioclavicular Joint Dislocation

PURPOSE/AIM

Options for surgery for acromioclavicular (AC) joint dislocation vary considerably. This study aimed to examine the functional and radiological results of patients who were operated on using the tightrope (TR) or clavicular hook plate (CHP) technique in the treatment for AC joint dislocation. Materials and methods: The data gathered from 35 consecutive patients who were operated on for AC joint dislocation were analyzed retrospectively in terms of their radiological and functional outcomes. Results: Thirty-two (91.4%) of the 35 patients were male and 3 (8.6%) were female. Thirty (85.7%) patients were classified as Rockwood type 3 and 5 (14.3%) as type 5. Twenty-one patients operated on using the TR technique were categorized as group 1, and 14 patients treated with the CHP technique formed group 2. Functional results were evaluated using the Constant-Murley shoulder scoring system; no statistically significant difference was observed between type 3 and 5 AC separation (p = 0.337). The mean Constant scores of type 3 and 5 injuries were 82.96 and 88.6, respectively. A significant relationship was noted between reduction quality and functional scores (p = 0.006). Postoperative osteoarthritis was seen in 12 (57.14%) patients in group 1 and 7 (50.00%) patients in group 2. In terms of surgery duration, 50.57 minutes in group 1 and 35.71 minutes in group 2 were noted. A statistically significant difference was found between the two groups in terms of surgery duration (p < 0.05). Conclusions: TR and CHP techniques, which do not differ significantly in terms of their clinical results, can be used safely in the treatment of AC separation.

Is coracoclavicular reconstruction necessary in hook plate fixation for acute unstable acromioclavicular dislocation?

Background

Acromioclavicular joint (ACJ) dislocation is a relatively common shoulder injury. For the treatment of cases of severe ACJ dislocation (Rockwood type III–V), hook plate fixation is an easy-to-master and minimally-invasive approach to surgical intervention. Over stress on the acromion following hook plate fixation often leads to acromial complications such as osteolysis and loss of reduction. We hypothesized that suspensory reconstruction alongside hook plate fixation might provide a superior stability and reduce complications as compared with hook plate fixation alone. The purpose of the study was to assess the clinical and radiographic outcomes of these two surgical modalities.

Methods

We retrospectively enrolled 49 patients with acute ACJ dislocation from May 2010 to December 2018. Among them, 19 patients received hook plate fixation only (HP group), and 19 underwent concomitant hook plate fixation and loop suspension fixation with two mersilene sutures (HM group). The demographic data of the patients were recorded and analyzed. All patients underwent a shoulder X-ray initially, immediately postoperatively, and at 1, 3, 6 and 12 months to measure the relative coracoclavicular distance (rCCD). Clinical assessment of shoulder function outcome was conducted using the Constant Murley Score (CMS); the University of California at Los Angeles (UCLA) Shoulder Score was also measured at the latest follow-up.

Results

There were no significant differences in the demographic data between the two groups. With regards to the CMS and the UCLA score, the HM group and HP group both had excellent outcomes, and no significant differences in scores were observed between groups (CMS: 93.90 ± 6.16 versus 94.47 ± 7.26, p = 0.47; UCLA score: 32.84 ± 2.91 versus 34.32 ± 1.16, p = 0.07). However, the HM group demonstrated substantial superiority in terms of maintenance of the rCCD over the HP group (91.47 ± 27.47 versus 100.75 ± 48.70, p = 0.015). In addition, there was less subacromial osteolysis in the HM group than the HP group (52.6% versus 15.8%, p = 0.038).

Conclusion

Both fixations yielded excellent functional outcomes. However, concomitant hook plate fixation with loop suspensory reconstruction demonstrated the fewer acromion complications and statistical differences in reduction maintenance with less clinical significance.

Young men in sports are at highest risk of acromioclavicular joint injuries: a prospective cohort study

PURPOSE

To study the incidence of acromioclavicular joint injuries in a general population.

METHODS

All acute shoulder injuries admitted to an orthopaedic emergency department were registered prospectively, using electronic patient records and a patient-reported questionnaire. The regional area was the city of Oslo with 632,990 inhabitants. Patients with symptoms from the acromioclavicular joint without fracture were registered as a dislocation (type II-VI) if the radiologist described widening of the joint space or coracoclavicular distance on standard anteroposterior radiographs. Patients without such findings were diagnosed as sprains (type I).

RESULTS

Acromioclavicular joint injuries constituted 11% of all shoulder injuries (287 of 2650). The incidence was 45 per 10⁵ person-years (95% confidence interval [CI] 40-51). 196 (68%) were diagnosed as sprains and 91 (32%) as dislocations. Median age of all acromioclavicular joint injuries was 32 years (interquartile range 24-44), and 82% were men. Thirty percent of all acromioclavicular joint injuries were registered in men in their twenties. Sports injuries accounted for 53%, compared to 27% in other shoulder injuries [OR 3.1 (95% CI 2.4-4.0; p < 0.001)]. The most common sports associated with acromioclavicular joint injuries were football (24%), cycling (16%), martial arts (11%), alpine skiing and snowboarding (both 9%), and ice hockey (6%).

CONCLUSION

Our study suggests that in the general population, one in ten shoulder injuries involves the acromioclavicular joint and young men in sports are at highest risk. A prognostic level II cohort study.

Midshaft clavicle fracture following osteosynthesis with a hook plate: a retrospective case analysis

PURPOSE

The clavicle hook plate has been commonly used to treat distal clavicle fractures and acromioclavicular (AC) joint dislocations; however, midshaft clavicle fracture at the medial end of the hook plate remains an underestimated complication. We aimed to discover the risk factors for this complication and the influence of these risk factors on patients and to suggest preventive surgical techniques.

METHODS

We retrospectively reviewed the records of 150 patients with acute distal clavicle fractures or acute AC joint dislocations treated by internal fixation with a clavicle hook plate. The patient demographics, the occurrence of midshaft clavicle fracture at the medial end of the hook plate, and functional outcomes were analyzed. The functional outcomes were evaluated with the American Shoulder and Elbow Surgeons (ASES) Shoulder Score and grading of the Constant shoulder score after the hook plate was removed.

RESULTS

In total, 17 patients had complicating midshaft clavicle fractures at the medial end of the hook plate. Elderly patients had a higher risk of developing this complication than young patients. The odds ratio was 4.4 (p < 0.05). The average ASES score and grading of Constant score of these patients were 74.1 and 16.3 points, respectively, which were significantly inferior to those of patients without complications (p < 0.001).

CONCLUSION

The incidence of midshaft clavicle fractures following osteosynthesis with a clavicle hook plate was not negligible, especially in elderly patients. This complication may impair shoulder function and quality of life. Awareness of this complication and the risk factors for this complication reminds us to perform such operations with caution.

Migration of K-wire into the cavum pleura after the reduction of acromioclavicular dislocation, a case report and review of literature

INTRODUCTION

The use of K-wire (Kirschner wire) in acromioclavicular dislocation was the first trans-articular fixation technique to be described.

PRESENTATION OF CASE

A 40-years-old man was presented to the emergency room (ER) with shortness of breath. He had a history of acromioclavicular dislocation two years ago, which had been treated using two K-wires and tension band wiring. The plain x-ray revealed left side pneumothorax with K-wire migrated into the left hemithorax. CT scan showed that K-wire migrated into the posterior cavum pleura. A chest tube was then inserted, and the removal of K-wire was performed using thoracoscopic assisted surgery followed by the removal of the remaining K-wire in the left shoulder. Three days post-surgery, the chest tube was removed, and the patient was discharged from the hospital.

DISCUSSION

This technique is easy and cheap, but it can cause lethal complications. K-wire can migrate into the area of vital organs, including the liver, heart, neck lung subclavian artery, and aorta.

CONCLUSION

K-Wire should be used cautiously for treating upper extremity injury, especially acromioclavicular dislocation, due to its lethal complications. This method is outdated and should be restricted as much as possible.

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.

Radiographic displacement of acute acromioclavicular joint dislocations fixed with AC TightRope

Background

The arthroscopic approach to acromioclavicular (AC) dislocation with methods such as AC TightRope fixation has reported radiographic failure rates between 18% and 50% with functional results graded as good or excellent. Our objective was to review the outcomes after arthroscopic fixation for acute AC joint dislocation using the TightRope device.

Methods

We reviewed the records of 52 patients, with a mean age of 31 years, who underwent arthroscopic fixation with the TightRope device for acute AC joint dislocation. Outcomes were evaluated using the Constant and University of California, Los Angeles scores. The coracoclavicular (CC) distance before and after surgery was compared by radiography.

Results

The mean follow-up period was 36.7 months (range, 6-65 months). Postoperatively, the mean Constant score was 97.13 and the mean University of California, Los Angeles score was 33.2. The CC distance was maintained in 73% of the patients, whereas partial loss of reduction occurred in 19.2% and failure of reduction occurred in 7.7%.

Conclusion

Arthroscopic fixation using the TightRope device for acute AC joint dislocation achieves satisfactory clinical outcomes. However, CC reconstruction appears to result in subluxation in cases with AC dislocation for a period of more than 10 days.

Can an acute high-grade acromioclavicular joint separation be reduced and stabilized without surgery? A surgeon's experience

INTRODUCTION

While the management of Rockwood type III injuries is still a topic of debate, high-grade Rockwood type V injuries are mostly treated surgically, to anatomically reduce the acromioclavicular (AC) joint and to restore functionality. In this case report, we present a method for non-operative reduction and stabilization of a high-grade AC joint injury.

CASE

A 31-year-old male orthopaedic resident sustained a Rockwood type V injury during a snowboarding accident. His AC joint was reduced and stabilized with an AC joint brace for six weeks. The brace provided active clavicle depression and humeral elevation. After removal of the brace the AC joint showed a nearly anatomic reduction. Six-month follow-up weighted X-ray views showed an AC joint which had healed in a Rockwood type II position and the patient returned to full pre-injury function with a satisfying cosmetic appearance.

CONCLUSION

Non-operative reduction and stabilization of high-grade AC joint separations seems to be a valuable treatment option. A "closed reduction and external fixation" approach with the aid of a dedicated AC joint brace can reduce the AC joint and keep it in place until ligamentous consolidation occurs, thus improving AC joint stability and cosmetic appearance without surgical intervention.

Surgical treatment of acute and chronic AC joint dislocations: Five-year experience with conventional and modified LARS fixation by a single surgeon

BACKGROUND

Different surgical fixation methods are available for the treatment of acromioclavicular (AC) joint dislocations. The aim of this study was to present the results of five years of experience with the Ligament Augmentation and Reconstruction System (LARS) fixation technique by a single surgeon.

METHODS

A single-center retrospective cohort study was performed. All patients treated for an AC joint dislocation with LARS fixation by the same surgeon between 2012 and 2016 (n = 20) were eligible for inclusion. All these dislocations were unstable injuries, Rockwood type-III or higher, requiring acute or chronic repair. The primary outcome was the QuickDASH score. Secondary outcomes were the Subjective Shoulder Value (SSV), Numerical Rating Scale (NRS) pain score, return to work, complications, and implant removal.

RESULTS

17 patients (85%) were available for final follow-up. The median follow-up was 23 months (IQR; 17─34). The median QuickDASH score was 7 (IQR; 2-18), the median SSV was 90 (IQR; 80-90), and the median NRS pain score was 2 (IQR; 1-3). Patients returned to work after a median of 8 weeks (IQR; 6-12). There was no significant difference in functional outcome scores between acute and chronic repair, or between the conventional and modified LARS fixation groups. There were two major complications requiring revision surgery, one ruptured LARS ligament and one case of deep wound infection. Implant removal was performed in one patient.

CONCLUSIONS

The LARS ligament fixation technique seems to be effective for the treatment of AC joint dislocations, resulting in good short- and mid-term patient-reported functional outcome. LARS fixation might also be an acceptable treatment option for active patients with symptomatic chronic AC dislocations.

LEVEL OF EVIDENCE

Level III, Retrospective Comparative Study, Treatment Study.

Repair of the entire superior acromioclavicular ligament complex best restores posterior translation and rotational stability

PURPOSE

The acromioclavicular ligament complex (ACLC) is the primary stabilizer against horizontal translation with the superior ACLC providing the main contribution. The purpose of this study was to evaluate the specific regional contributions in the superior half of ACLC, where the surgeon can easily access and repair or reconstruct, for posterior translational and rotational stability.

METHODS

The superior half of ACLC was divided into three regions; Region A (0°-60°): an anterior 1/3 region of the superior half of ACLC, Region B (60°-120°): a superior 1/3 region of the superior half of ACLC, and Region C (120°-180°): a posterior 1/3 region of the superior half of ACLC. Fifteen fresh-frozen cadaveric shoulders were used. Biomechanical testing was performed to evaluate the resistance force against passive posterior translation (10 mm) and the resistance torque against passive posterior rotation (20°) during the following the four conditions. (1) Stability was tested on all specimens in their intact condition (n = 15). (2) The ACLC was dissected and stability was tested (n = 15). (3) Specimens were randomly divided into three groups by regions of suturing. Stability was tested after suturing Region A, Region B, or Region C (n = 5 per group). (4) Stability was tested after suturing additional regions: Region A + B (0°-120°), Region B + C (60°-180°), or Region A + C (0°-60°, 120°-180°, n = 5 per group).

RESULTS

The translational force increased after suturing Region A when compared with dissected ACLC (P = 0.025). The force after suturing Region A + B was significantly higher compared to the dissected ACLC (P < 0.001). The rotational torque increased after suturing Region A or Region B compared with dissected ACLC (P = 0.020, P = 0.045, respectively). The torque after suturing the Region A + C was significantly higher compared to the dissected ACLC (P < 0.001).

CONCLUSION

The combined Region A + B contributed more to posterior translational stability than Region B + C or Region A + C. In contrast, combined Region A + C contributed more to posterior rotational stability than Region A + B or Region B + C. Based on these findings, surgical techniques restoring the entire superior ACLC are recommended to address both posterior translational and rotational stability of the AC joint.

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

PURPOSE

Acromioclavicular joint reconstruction is a well-established and frequently performed procedure. Recent scientific and commercial interest has led to a drive to develop and perform surgical techniques that more reliably restore horizontal stability in order to improve patient outcomes. The aim of this systematic review was to evaluate the biomechanical evidence for procedures directed at restoring horizontal stability and determine whether they are associated with superior clinical results when compared to well-established procedures.

METHODS

A review of the online databases Medline and EMBASE was conducted in accordance with the PRISMA guidelines on the 23rd December 2017. Biomechanical and clinical studies reporting either static or dynamic horizontal displacement following acromioclavicular joint reconstruction (Coracoclavicular reconstruction or Weaver-Dunn) were included. In addition, biomechanical and clinical studies reporting outcomes after additional augmentation of the acromioclavicular joint were included. The studies were appraised using the Methodological index for non-randomised studies tool.

RESULTS

The search strategy identified 18 studies eligible for inclusion: six biomechanical and 12 clinical studies. Comparative biomechanical studies demonstrated that acromioclavicular augmentation provided significantly increased horizontal stability compared to the coracoclavicular reconstruction and Weaver-Dunn procedure. Comparative clinical studies demonstrated no significant differences between coracoclavicular reconstruction with and without acromioclavicular augmentation in terms of functional outcomes (American Shoulder and Elbow Surgeon and Constant score), complication or revision rates. However, one comparative study did demonstrate an improvement in Taft (p = 0.018) and Acromioclavicular Joint Instability scores (p = 0.0001) after acromioclavicular augmentation.

CONCLUSION

In conclusion, coracoclavicular reconstruction with augmentation of the acromioclavicular joint has been shown to provide improved horizontal stability in both biomechanical and clinical studies compared to isolated coracoclavicular reconstruction. However, comparative studies have shown no clinical advantage with respect to American Shoulder and Elbow Surgeon or Constant scores and, therefore, the results of this systematic review do not support acromioclavicular augmentation in routine clinical practice.

LEVEL OF EVIDENCE

IV.

Osteomyelitis post acromioclavicular joint reconstruction

Acromioclavicular joint (ACJ) injury is a common shoulder injury. There are various techniques of ACJ reconstruction. Superficial infection after ACJ reconstruction is not an uncommon complication. However, osteomyelitis post ACJ reconstruction has never been highlighted as a possible complication. Our patient is a 31-year-old male who sustained a Rockwood 5 ACJ dislocation and had anatomical ACJ reconstruction with autogenous gracilis and semitendinosus graft. Our technique involved the anatomical reconstruction of the ACJ and the coracoclavicular ligament with the usage of two bioscrews and the temporary stabilisation of the ACJ with two k-wires. As in any orthopaedic surgery, infection is often disastrous especially when the surgery involves implants. It can be disastrous with high morbidity to the patient as well as a costly complication to treat. Therefore, we wish to highlight this case as despite its rarity, osteomyelitis can be devastating to the patient and should be prevented if possible.

Biomechanical comparison of two biplanar and one monoplanar reconstruction techniques of the acromioclavicular joint

INTRODUCTION

The purpose of this proof-of-concept study was to investigate the biomechanical performance of two surgical techniques, namely (1) the double Tight-Rope fixation with an additional acromioclavicular FiberTape fixation (DTRC) and (2) the fixation of the clavicle to the acromion and coracoid in a bipodal manner (Bipod) using a Poly-Tape and FiberTape. Both techniques intend to address vertical and horizontal instability after acromioclavicular dislocation. They were compared with the commonly used (3) double Tight-Rope (DTR) technique, which only stabilizes the clavicle to the coracoid.

MATERIALS AND METHODS

The acromioclavicular joint (ACJ) of 18 composite Sawbone shoulder specimens (6 per reconstruction group) were tested for posterosuperior elongation (70N cyclical load, 1500 cycles), load-to-failure and stiffness.

RESULTS

After 1500 cycles, the DTRC, Bipod and DTR group showed an elongation of 0.45 mm (SD 0.14 mm), 1.19 mm (SD 0.54 mm), and 0.46 mm (SD 0.15 mm), respectively. Although the elongation of the Bipod group was increased when compared to the other two groups (Bipod versus DTRC p = 0.008; Bipod versus DTR p = 0.006), the difference was less than 0.7 mm. The DTRC showed a higher load-to-failure of 656.1N (SD 58.1 N) compared to the Bipod [531.1 N (SD 108.2N) (p = 0.039)] and DTR group [522.8 N (SD 32.8 N) (p = 0.033)].

CONCLUSION

The DTRC and the DTR group resulted in similar low elongation, while the elongation in the Bipod technique was slightly higher. Even though this difference of 0.7 mm shows statistical significance, it most likely has no clinical relevance. When testing in posterosuperior direction, which is the clinically relevant load vector, an additional fixation of the clavicle to the acromion did not reduce elongation in this study. It is, furthermore, questionable if the benefit of an increased load-to-failure in combination with no improvement in elongation and stiffness as seen in the DTRC group outweighs the possible risks and increased costs coming with the DTRC refixation.

Three intrasubstance failures of a LARS™ ligament used for ligament reconstruction

We report three cases of intrasubstance failure of a LARS™ (Ligament Augmentation and Reconstruction System) artificial ligament used for acromioclavicular joint reconstruction. The LARS™ ligament failed within four months of the index procedure. All patients underwent a revision procedure following an unsuccessful trial of conservative management. A modified second loop technique was employed during the revision procedure for all cases using the LARS™ ligament. All three patients achieved full recovery to pre-injury level function.

Fifteen-degree clavicular hook plate achieves better clinical outcomes in the treatment of acromioclavicular joint dislocation

OBJECTIVE

Clavicular hook plate application is one of the most commonly used treatment methods for acromioclavicular (AC) joint dislocation, although it may cause multiple postoperative complications. We modified the regularly used 0° hook plate to 15° and compared the clinical outcomes of these two hook plates for treatment of AC joint dislocation.

METHODS

Forty-three patients with acute AC joint dislocation were randomly enrolled (0° hook plate, 20 patients; 15° hook plate, 23 patients). The American Shoulder and Elbow Surgeons (ASES) and visual analog scale for pain (VASP) scores were evaluated preoperatively and at 3 days and 1, 2, 3, and 6 months postoperatively and compared between the two groups.

RESULTS

Compared with the preoperative scores, the 6-month postoperative ASES score gradually increased but the VASP score decreased in both groups. Furthermore, the ASES and VASP scores were significantly different between the two groups at every postoperative time point.

CONCLUSION

The 15° hook plate is superior to the 0° hook plate in reducing shoulder pain and improving postoperative recovery in the treatment of AC joint dislocation.

LEVEL OF EVIDENCE

Level III; Treatment study (retrospective comparative study).

Analysis of the bony geometry of the acromio-clavicular joint

Background

The primary goal of this study was to analyse the anatomic configuration of the acromio-clavicular joint in a healthy population to be able to develop a classification in a second step. On the basis of the primary findings a secondary goal was to find potential clinical indications in refer to AC-joint dislocation and lateral clavicle fractures.

Methods

The upper thoracic aperture including both shoulder joints as well as both sterno-clavicular joints was retrospectively reformatted in a bone kernel in axial orientation with 0.6 mm slice thickness out of existing multiple trauma or post mortem computed tomography (CT) scans. The DICOM data was converted into the STL file format using a three dimensional (3D) reconstruction software (Smartbrush, Brainlab, Feldkirchen, Germany). The data analysis was performed using a 3D—Computer Aided Detection (CAD) Software (BioCAD, Technical University Munich, Germany). For the analysis, the angle between the cranial surface of the acromion and the tangent to its articular surface was evaluated. Accordingly, the angle between the cranial surface of the clavicle and the tangent to its articular surface was assessed.

Results

Overall CT-datasets of 80 healthy patients (40 males, 40 females, mean age 45 ± 8 years) were enrolled and evaluated regarding the configuration of the AC-joint. In this context, three statistically significant (p < 0.001) different configurations of the AC-joint in terms of overhanging acromion, neutral type, overhanging clavicle were identified. The “overhanging acromion” type of AC-joint configuration turned out to be the most common type (46.2%) followed by the “neutral type” (38.4%) and finally the “overhanging clavicle type” (15.4%).

Conclusions

We assume that the shown differences of the AC joint congruency might play an important role in the development of different shoulder injuries resulting from the similar trauma mechanism. However, the proof of these assumptions will be the focus of future studies.

A novel hybrid fixation (coracoclavicular screw supplemented with K-wire) for the treatment of acute acromioclavicular joint dislocation: A prospective study

OBJECTIVE

The aim of this study was to compare the radiological and clinical outcomes of clavicular hook plate fixation and the coracoclavicular lag screw supplemented with K-wire fixation in the treatment of acute acromioclavicular joint dislocation.

METHODS

Between January 2012 to December 2015, 81 patients with acute acromioclavicular joint dislocation were included in this prospective study. 43 patients were treated with clavicular hook plate fixation (Group A) and 38 patients were treated with coracoclavicular lag screw supplemented with K-wire fixation (Group B). Incision length, operation duration, blood loss volume, intraoperative fluoroscopy times and length of hospitalization were recorded. Radiographic outcomes, functional outcomes and complications were also recorded.

RESULTS

Both two groups could achieve good radiographic and functional outcomes after operation. Group B exhibited significantly shorter operation duration, shorter length of incision, less blood loss volume and shorter length of hospitalization than Group A (P < 0.001). In addition, significant difference could be found between the two groups regarding the VAS scores three month postoperatively and the final follow-up (P < 0.001). However, there was no significant difference in radiographic and functional outcomes between the two groups (P > 0.05).

CONCLUSION

The two groups can both achieve satisfactory radiological and functional outcomes in treating acute AC joint dislocation. However, CC screw fixation supplemented with K-wire exerts some advantages regarding the incision length, operation duration, blood loss volume, length of hospitalization. Furthermore, it can better relieve the pain caused by dislocation. Therefore, the novel hybrid fixation (CC screw fixation supplemented with K-wire) provides an alternative treatment for acute AC joint dislocation.

C-arm navigation: A prospective trial

INTRODUCTION

To compare percutaneous minimally invasive repair (PMIR) of acute acromioclavicular (AC) joint dislocation under ultrasound guidance (PMIR-UN) vs. C-arm navigation (PMIR-CN).

HYPOTHESIS

PMIR-UN has similar functional and radiographic outcomes as PMIR-CN.

MATERIALS AND METHODS

We treated 48 patients with acute grade III or V AC joint dislocation with surgical reduction and fixation with Kirschner wires and cannulated screws. The patients were randomly divided into a PMIR-UN group (n=24) and a PMIR-CN group (n=24). We assessed functional outcomes, operative duration, incision length, and intraoperative radiation exposure. Shoulder joint function was evaluated with the Constant-Murley score, and postoperative efficacy was evaluated using the Karlsson criteria.

RESULTS

The median follow-up duration was 13 months (range, 8-18 months). Satisfactory functional outcomes were obtained in both groups. Incision length, incidence of postoperative infection, pin migration, and postoperative efficacy did not differ between the two groups. Operative duration and intraoperative radiation dose were significantly greater in the PMIR-CN group than in the PMIR-UN group (P<0.05). Kirschner wires were removed at 4 weeks after surgery, and cannulated screws were removed at 12 weeks after surgery in both groups.

DISCUSSION

Based on the satisfactory results obtained in all patients, we conclude that PMIR-UN is a safe, easy, and reliable technique for the treatment of acute grade III or V AC joint dislocation.

TYPE OF STUDY

Low-powered prospective randomized trial.

LEVEL OF EVIDENCE

Level II.

Treatment of AC dislocation by reconstructing CC and AC ligaments with allogenic tendons compared with hook plates

BACKGROUND

The purpose of this study was to compare outcomes between allograft reconstruction and hook plate fixation for acute dislocation of the acromioclavicular joint with a minimum 2-year follow-up.

METHODS

A retrospective comparative study of patients treated for acute acromioclavicular joint dislocation from February 2010 to December 2014 in our hospital, consisting of 16 patients who were followed-up, was performed. Eight patients were treated for acute AC dislocation and underwent surgical reconstruction as follows: the coracoclavicular and acromioclavicular ligaments were reconstructed with the allogenic tendon. The other eight patients were treated with hook plates to maintain the AC joint reset. At the latest follow-up, radiographic analysis and the Constant and University of California-Los Angeles (UCLA) scores were used to evaluate shoulder function. The satisfaction of the patients in terms of the efficacy and visual analog scale (VAS) data were also recorded.

RESULTS

After an average follow-up of 30.3 months (range 24-46 months), no patient had dislocated their joint again at the final follow-up based on X-ray examination. The Constant score was 94.4 for the allogenic tendon group and 93.8 for the hook plate group (P = 0.57). According to the UCLA scale (P = 0.23) or VAS (P = 0.16), we found no significant difference between the two groups. All patients reported that they were very satisfied or satisfied with the outcome of surgery, and no significant difference (P = 0.08) was found between the two groups.

CONCLUSIONS

The use of allogenic tendon for reconstruction of the coracoclavicular and acromioclavicular ligaments shows excellent outcomes in terms of the recovery of clinical function or radiographic outcomes for acute AC dislocation. Compared with the hook plate, the hardware did not need to be removed.