Efficacy comparison between clavicular hook plate combined with coracoclavicular ligament reconstruction and simple hook plate for acute acromioclavicular joint dislocation

Objective To compare clinical and radiographic outcomes of hook plate fixation and coracoclavicular ligament reconstruction in the treatment of acute unstable acromioclavicular joint dislocation. Methods Fiftypatients with acute unstable dislocation of the acromioclavicular joint were enrolled in the study and divided into two groups according to the treatment modality, ie, internal fixation with a hook plate group (Group I, 20 cases) and coracoclavicular ligament reconstruction group (Group II, 30 cases). The clinical outcomes were evaluated using Constant- Murley score (CMS) and visual analog scale (VAS) and the radiographic outcomes assessed based on coracoclaviculardistance (CCD). Results The mean CMS score was(94.4±6.97) points and (95.87±3.50) points in Groups I and II, respectively, with no statistical difference. The mean VAS scores at the final follow-up was (0.85±0.93) points and (0.87±0.82) points in Groups I and II, respectively, with no statistical difference. The acromioclavicular joints were well reduced in both groups. CCDwas improved from preoperative (15.91±5.29)mm to postoperative (6.94±2.90)mm in Group I, with an improvement of (263.00±181.45)%, and from preoperative (15.10±6.43)mm to postoperative (5.54±2.10)mm in Group II, with an improvement of (293.67±116.39)%. The improvement in Group I was not significantly superior to that in Group II(P>0.05) Subluxation was observed in both groups, with higher incidence in Group II(26.7%) than that in Group I(15%). However, erosions of the acromion undersurface and osteoarthritis of acromioclavicular were only observed in group I, with an incurrence of 80% and 25%, respectively. Furthermore, coracoclavicular ligament ossification shown more frequently in group I (35%) than group II (13.3%). Conclusions For acute unstable acromioclavicular joint dislocation, hook plate fixation and coracoclavicular ligament reconstruction can attain comparable satisfactory clinical and radiographicoutcomes. Hook plate should be moved earlier to avoid the complication. Subluxation is the major complication of ligament reconstruction. Key words: Dislocation, Acromioclavicular joint; Hook plate fixation; Endobutton; Ligament reconstruction

Objective To evaluate the curative effect of conjoined tendon transfer for coracoclavicular ligament reconstruction in the treatment of Rockwood grades Ⅲ-Ⅳ acromioclavicular joint dislocation. c Methods A retrospective case control study was performed for 64 cases of acromioclavicular joint dislocation admitted from October 2007 to August 2014. There were 53 males and 11 females, with age of (43.8±10.5)years (range, 23 to 65 years). Rockwood grade Ⅲ was seen in 27 cases and grade -Ⅳ in 37. According to the treatments, 26 cases underwent proximally based conjoined tendon transfer for coracoclavicular ligament reconstruction combined with clavicular hook plate (ligament reconstruction group) and 38 cases only treated with clavicular hook plate (internal fixation group). Visual analogue scale (VAS), Constant shoulder score and postoperative complications were compared between the two groups before and after operation. Results All patients were available for a mean follow-up of 3.7 months (range, 2 to 4 months). VAS was (7.58±1.03)points in ligament reconstruction group and (7.15±1.03)points in internal fixation group before surgery (P>0.05), and was (2.38±0.94)points in ligament reconstruction group and (2.08±0.99)points in internal fixation group 3 months after operation (P>0.05). Constant shoulder score was (86.46±6.59)points in ligament reconstruction group and (87.68±6.59)points in internal fixation group after operation (P>0.05). Six cases (16%) had recurrent joint dislocation in internal fixation group, while none of the patients in ligament reconstruction group had recurrence (P<0.05). Conclusion Improved procedure of proximally based conjoined tendon transfer for coracoclavicular ligament reconstruction can effectively reduce the recurrence rate of acromioclavicular joint dislocation. Key words: Acromioclavicular joint; Dislocations; Fracture fixation, internal

Comparison of hook plate with versus without double-tunnel coracoclavicular ligament reconstruction for repair of acute acromioclavicular joint dislocations: A prospective randomized controlled clinical trial

Background In recent years, the incidence of acromioclavicular joint dislocation has been increasing. The main causes are falling from high places, car accidents and sports injuries. Rockwood et al. classified AC joint dislocation into 6 types, which has certain guiding significance for the choice of treatment methods. The conservative treatment of Rockwood type I and II dislocation is satisfactory, while type III and other dislocations require surgical treatment to repair the completely broken coracoclavicular ligament. A large number of surgical methods for acromioclavicular joint dislocation have been reported in literatures, but the surgical choice is controversial.With the development of biomechanics research and material science, more and more surgeons tend to reconstruct coracoclavicular ligament to treat AC joint dislocation. Most surgeons regard the coracoclavicular ligament as a single bundle without reconstructing the trapezoidal ligament and the conical ligament separately. The double-bundle reconstruction reported in a few literatures is not an exact anatomical reconstruction. In this paper, we introduce a method of complete anatomical reconstruction of coracoclavicular ligament with double-bundle Endobutton loop-plate and Ethibond-2 suture according to the anatomy origin. The method was applied to 22 patients with type III-V acromioclavicular joint dislocation, including fresh or old injuries. They were followed up for at least 12 months to evaluate the early clinical outcome. Methods 1. Patient information: Twenty patients with acromioclavicular joint dislocation diagnosed by Jiangsu People's Hospital from August 2013 to June 2015 were included. Another 2 patients from September to December 2015 in Nanjing Qixia District Hospital were also included in this study. There were 15 males and 7 females, with an average age of 44.5 (17-71) years. The dislocation of acromioclavicular joint was unilateral, including 9 cases on the left side, 13 cases on the right side and 13 cases on the dominant side. The causes of injuries included 12 falls, 7 car accidents and 3 sports injuries. X-ray and CT was performed on bilateral shoulder before operation to determine the Rockwood classification, including 7 cases of type III, 1 case of type IV and 14 cases of type V. The including criteria was Rockwood III or above of acromioclavicular joint dislocation and no other history of fracture, dislocation or trauma of the affected limb. The average operation time from injury to reconstruction of coracoclavicular ligament was 24.5 (2-182) years. Old injuries defined as that the treatment was delayed for more than 3 weeks after injury. There were 6 cases of old dislocation and 16 cases of fresh dislocation. This study was approved by the Medical Ethics Committee of the First Affiliated Hospital of Nanjing Medical University. All patients signed the informed consent and agreed to complete anatomical reconstruction of coracoclavicular ligament for acromioclavicular dislocation. 2. Operative methods: Under general anesthesia, we took the beach chair position. A 10 cm long arc incision was made from the distal clavicle to the tip of coracoid process. The skin, subcutaneous, superficial fascia and deep fascia were incised to expose the upper surface of distal clavicle. During this process, the insertion of deltoid and trapezius muscle were dissected minimally, and the coracoid process was exposed through the groove between deltoid and pectoralis major muscles, so as to avoid injuring the cephalic vein.According to the anatomical position of the trapezoidal ligament and the conical ligament, the coracoid process and clavicle were drilled with a 2.0 mm K-wire. The insertion point on clavicle is the projection of trapezoidal and conical ligament on supraclavicle surface, and the outlet point is the attachment of the trapezoidal and conical ligament on the subclavicle surface. The insertion point on the coracoid process is the attachment of conical and trapezoid ligament on the upper surface. The outlet point on coracoid process is on basal surface. The drill diameter should be 3.0 mm to avoid penetrating the cortex of the coracoid process and keep the adjacent bone channels at a certain distance.A double-folded No.2 Ethibond suture A was passed through the clavicle and coracoid tunnel in turn under the guide of suture passer. The acromioclavicular joint is repositioned by manipulation. The acromioclavicular joint is temporarily fixed with a 2.0 mm K-wire. The full reduction of acromioclavicular joint is confirmed by fluoroscopy during operation. The length of the loop is measured by comparing two ethibond sutures of the same length. A suitable size of endobutton (A) is selected according to the measured length. Then pass another No.2 ethibond suture B through the first hole and the fourth hole of the looped plate A, and then take a No.2 ethibond suture C through the loop . Under the guidance of suture A, suture B and C were passed through the tunnel of clavicle and coracoid process. Suture B is gently pulled to place the plate A at the base of coracoid process. Suture C is gently pulled to make the loop pass through the tunnel of coracoid process and clavicle. A plate B without loop is placed in the loop passing through the first and fourth hole of plate B, respectively. After removing K-wire, fluoroscopy showed satisfactory reduction and reliable fixation . Then we explore the acromioclavicular joint, using absorbable suture to strengthen the acromioclavicular joint capsule. After a large amount of saline irrigation, close the wound layer by layer. 3. Postoperative rehabilitation: The patients were encouraged to increase the active ROM of shoulder after 6 weeks. Gradual resistance training was postponed to 8 weeks after operation. Normal physical work and physical exercise could be resumed 6 months after operation. 4. Functional Evaluation: VAS score and Constant score were performed at 3, 6 and 12 months after operation. AP and axillary view of bilateral shoulder joints were re-examined. Coracoclavicular space of affected side and healthy side was measured before and after operation. Coracoclavicular space refers to the vertical distance between the lowest point of the subclavicle surface and the highest point of the upper surface of the coracoid process. All scores and measurements were independently completed by three physicians. 5. Statistical Analysis: Each data is averaged by three times of evaluation results, and all data are expressed by mean±standard deviation. Normality test was performed on each group of data. Paired t test and Wilcoxon test were used before and after operation. P<0.05 showed significant difference. Data were processed by SPSS l8.0 software. Results The patients were followed up for 12 to 24 months (the average follow-up time was 17.7 + 4.0 months) . The visual analogue score of pain decreased from 5.0 to 0.2 after 12 months (P 0.91,) . Four patients with AC joint arthritis complained of mild pain in the shoulder joint. Nonsteroidal anti-inflammatory and analgesic drugs were given orally with good results. Constant score did not decrease significantly. During the follow-up period, no serious complications such as re-dislocation and clavicular or coracoid process fracture were found. Conclusions Complete anatomical reconstruction of coracoclavicular ligament with double-bundle Endobutton is a safe, reliable and novel surgical method. It has been applied to the treatment of Rockwood III-V fresh or old acromioclavicular dislocation with good clinical results. Key words: Acromioclavicular joint dislocation; Coracoclavicular ligament; Complete anatomical reconstruction; Trapezoidal ligament; Conical ligament

Object To analyze reasons of complications induced by the clavicle hook plate in treatment of acute distal clavicle fractures and acute acromioclavicular joint dislocations,and to investigate corresponding solutions.Methods Seventy nine clavicle hook plates were facilitated in the treatment of acuteb distal clavicle fractures (47 cases) and acute high grade acromioclavicular joint dislocations (32 cases) from May 2006 to May 2009.There were 51 males and 28 females,with an average age of 42.6 years(range,15 to 78 years).Seventy eight patients underwent plate removal operation.Forty patients agreed to accept the CT examination to evaluate the acromion erosion around the plates.Among them,7 patients received further CT examination 3 months after the removal surgery.The shoulder function was evaluated by the constant scores at the final follow-up.Results All patients were followed up for at least one year (range,12 to 30 months).The mean duration for retaining the hook plate was 8.3 months with the mean Constant scores 92 points in the acute distal clavicle group; 7.2 months with the mean Constant scores 95 points in the acute acromioclavicular joint dislocation group.There were 8 kinds,totally 105 complications happened in 78 patients (98.7％).The complications were classified into four groups: (1) Due to the specific working mechanism of the plate(88/105,83.8％);(2) Due to the iatrogenic errors(12/105,11.4 ％);(3) Due to insufficiency design of the plate(3/105,2.9％);(4) Due to the etiology of the injury itself(2/105,1.9％).Conclusion The complication rate is unexpected higher.Most complications are unavoidable due to specific working mechanism of the plate.The patients should be well informed about this preoperatively in order to avoid the possible legal trouble.The iatrogenic errors can be avoided with proper indications and improved surgical techniques.The design of the plate needs to be improved,and the hook plate should be removed as early as possible. Key words: [Key words] Clavicle; Fractures, bone; Acromioclavicular joint; Dislocations; Fracture fixation, internal; Postoperative complications

To explore the clinical outcomes of acromioclavicular joint (ACJ) dislocation treated with coracoclavicular ligament (CCL) reconstruction using lateral half of conjoined tendon and tractusiliotibialis with hook plate fixation. Comparative study on their advantages and disadvantages in order to provide the materials for the clinic. From June 2005 to June 2012, the patients with Rockwood type III or severer ACJ dislocation were randomly divided into 2 groups. They underwent CCL reconstruction using lateral half of conjoined tendon (conjoined tendon reconstruction group, n = 36) and tractusiliotibialis (tractusiliotibialis reconstruction group, n = 38) with subsequent fixation of hook plates. During the follow-up, the AC and CC distances were measured on postoperative plain films after a removal of hook plates. And the outcomes were assessed according to Karlsson criteria and Constant-Murley shoulder score. Ranked data were analyzed with the use of χ2 test and measurement date with two-sample t test. Results A total of 74 patients were followed up for an average of 20 (12 - 24) months. No significant inter-group differences existed in age, gender, injured side or classification. And there was no statistical difference in ACor CC distance between two groups within 6 months (P > 0. 05) after a removal of hook plates. The AC and CC distances of conjoined tendon reconstruction group were larger than those of tractusiliotibialis reconstruction group (t = 2. 313, P = 0. 026; t = 2. 114, P = 0. 041) within 12 months. The AC and CC distances of 12 months were both larger than those of 6 months (t =2. 631, P =0. 017; t = 2. 297, P = 0. 032). According to the Constant-Murley shoulder score, conjoined tendon reconstruction group was less than tractusiliotibialis reconstruction group (85. 2 ± 10. 2 vs 93. 1 ± 6. 9, t = 2. 965, P = 0. 006). According to the Karlsson Criteria, the excellent and good rate of functional recovery was 75. 00% in conjoined tendon reconstruction group versus 94. 74% in tractusiliotibialis reconstruction group (χ2 = 8. 111, P = 0. 044). The efficacy of Rockwood type III acromioclavicular joint dislocation for reconstructing coracoclavicular ligament using tractusiliotibialis is better than conjoined tendon. The AC and CC distances increase after a removal of hook plates while it is more obvious for conjoined tendon tractusiliotibialis reconstruction.

Objective To compare the outcomes of arthroscopic coracoacromial ligament augmentation and clavicular hook plating in treatment of acromioclavicular joint dislocation. Methods From March 2008 to March 2012, 47 patients with acute closed type Ⅲ-Ⅴ acromioclavicular joint dislocations underwent an arthroscopic repair with coracoacromial ligament augmentation and suture (ligament augmentation group, 23 patients) and with AO clavicular hook plate (hook plate group, 24 cases). Mean age of the patients (32 males and 15 females) was 34.8 years (range, 17-45 years). There were 32 left and 15 right injuries. Postoperative outcome was assessed through radiographic examination, American Shoulder and Elbow Surgeon (ASES) score and Karlsson scoring method. Results Mean period of follow-up was 18 months (range, 12-24 months). In ligament augmentation group ASES score improved from (28.7±7.3)points preoperatively to (96.3±6.9)points postoperatively (t=51.34, P<0.05). In hook plate group ASES score improved from (29.3±7.6)points preoperatively to (83.6±8.5)points postoperatively (t=43.78, P<0.05). Postoperative radiographic examination showed well joint reduction of all patients. Good and excellent results with the Karlsson score accounted for 96% (22/23) in ligament augmentation group and 71% (17/24) in hook plate group (χ2=9.05, P<0.05). Conclusions Efficacy of coracoacromial ligament augmentation and suture for the treatment of acromioclavicular joint dislocation is better than clavicular hook plate. Coracoacromial ligament augmentation and suture are associated with lower incidence of shoulder pain and shoulder activity limitation, shorter recovery time, fewer complications and early activities. Key words: Shoulder dislocation; Arthroscopy; Coracoacromial ligament

Background Acromioclavicular joint dislocation is mainly caused by direct violence, and its pathological basis is mainly the injuries of acromioclavicular joint capsule, coracoclavicular ligament and acromioclavicularligament in different levels, which causes acromioclavicular joint to be unstable. The acromioclavicular joint dislocation is one of the common injuries in shoulder, and its incidence rate accounts for 4.40% -5.89% of the systematic fracture and dislocation and 12% of the shoulder joint injury. Currently, the consensus has beenreached that Rockwood types I, II and IIIa acromioclavicular joint dislocation can achieve satisfactory result with conservative treatment,whilethesurgical treatment is indicated for the acromioclavicular joint dislocationof Rockwood type IIIb or above . Traditional clavicular hook plate for the treatment of acromioclavicular joint dislocation has many complications. On the other hand, the arthroscopic minimally invasive reconstruction of acromioclavicular joint stability becomes the preferred choice for orthopedic surgeon. Twin Tail TightRope Y-shaped fixation is a new generation of treatment method. Meanwhile, it satisfies the rigid anatomical reduction of acromioclavicular joint, allowing the postoperative micromotion of acromioclavicular joint with small incision,early functional rehabilitation and no need for the removal of internal fixator. Objective To evaluate the early clinical efficacy of Twin Tail TightRope Y-shaped fixation in the treatment of acute acromioclavicular dislocation. Methods From June 2015 to June 2017, a total of 16 patients with acute acromioclavicular dislocation were treated with arthroscopic Twin Tail TightRope Y-shaped fixation, and the data was retrospectively analyzed. The VAS, and Constant-Murley scoring systems were used to evaluate the surgical effect. Results All patients were followed up for 3-12 months with an average of (6.48±1.51) months. No neurovascular injury or incision infection occurred. During the last follow up, no reduction loss, clavicular stress fracture, coracoid process cutting or other complication occurred. During the last follow up: the postoperative VAS score (0.36±0.04) was lower than the preoperative score (7.46±1.24) ; the postoperative Constant-Murley score (90.07±3.13) was higher than the preoperative score (46.13±3.25) . Conclusion The Twin Tail TightRope Y-shaped fixation for the treatment of acute acromioclavicular dislocation can effectively solve the problems of postoperative horizontal and anteroposterior instabilities.This technique has relatively low incidences of clavicle and coracoid process fractures, and the arthroscopic operation can reduce surgical injury and improve accuracy. Key words: Acromioclavicular joint dislocation; Twin Tail TightRope; Y-shapedfixation; Arthroscopy

Objective To compare the clinical outcomes of palmaris longus tendon(PLT)and iliotibial tract fascia graft(ITFG)for coracoclavicular ligament(CCL)reconstruction combined with hook plate fixation in the treatment of acromioclavicular joint(AGJ)dislocation. Methods A retrospective study was conducted to evaluate the outcomes of 68 patients with ACJ dislocation of Rockwood type Ⅲ and above who had been treated in our department with CCL reconstruction using PLT or ITFG in addition to hook plate fixation from January 2008 to January 2014. They were 57 males and 11 females, with an average age of 36. 1 years(range, from 19 to 55 years). The patients were divided into 2 groups according to their grafts used in CCL reconstruction: 36 cases in PLT group and 32 in ITFG group. They were firstly treated with CCL reconstruction followed by hook plate fixation. The hook plates were removed at 6 months after operation. The acromioclavicular and coracoclavicular distances were measured on the postoperative anteroposterior radiographs of the injured shoulders. The outcomes were assessed at the final follow-ups according to Constant-Murley shoulder score and Karlsson criteria. The 2 groups were compatible without significant differences in preoperative general data(P> 0. 05). Results The 68 patients were followed up for an average of 18 months(range, from 16 to 22 months). The acromioclavicular and coracoclavicular distances measured in PLT group at 12 months after operation were significantly larger than those measured in ITFG group(P 0. 05). Conclusion In the treatment of ACJ dislocation of Rookwood type Ⅲ and above, CCL reconstruction using ITFG may lead to better radiographic outcomes than that using PLT, though the 2 grafts lead to similar functional recovery of the injured shoulders. Key words: Acromioclavicular joint; Dislocations; Ligament; Reconstructive surgical procedures

Objective: The efficacy of the tight-rope (TR) technique and clavicular hook plate (CHP) for the treatment of acute acromioclavicular (AC) joint dislocation is controversial. This meta-analysis aimed to evaluate which method is more appropriate for the treatment of acute AC joint dislocation. Methods: We systematically searched the PubMed, EMBASE, Scopus, ISI Web of Science, Chinese VIP Database, and Chinese Wan-Fang databases from inception to January 2018 using the search term “acromioclavicular joint dislocation AND hook plate.” All prospective and retrospective controlled trials that had compared functional scores, pain scores, reduction loss rates, coracoclavicular (CC) distances, and complications between TR and CHP for acute AC joint dislocation were identified. A total of 13 of 587 studies with 732 patients were included. TR was preferential to CHP for AC joint dislocation given its higher Constant–Murley score, lower Visual Analog Scale pain score, and comparable reduction loss rate and CC distance. Subgroup analyses of the surgical type of TR did not affect the outcome. Results: The TR technique appears to be associated with better functional recovery and less pain than CHP. In addition, it does not increase the risk of reduction loss, CC distance, or operation time. It is also not associated with other complications except the implant migration, and does not require removal of the internal fixation. Conclusions: Thus, our results indicated that for AC joint dislocation, the TR technique may be preferential.

Objective To explore the clinical efficacy and the technical advantages between minimal incision triple-endobutton to the traditional Arbeitsgemeinschaftfur Osteosynthesefragen (AO) / Association for the Study of Internal Fixation (ASIF)clavicular hook plate technique for the treatment of fresh Rockwood Ⅲ acromioclavicular joint dislocation. Methods Data were collected from December 2012 to December 2016, minimal incision triple-endobutton technique was used to treat fresh Rockwood type acromioclavicular dislocation patients (group T) and using clavicular hook plate internal fixation patients (group C) data. Group T were 32 cases, and group C were 35 cases. The follow-up time points were postoperative one week, two weeks, one month, three months, six months and twelve months of via X-ray examination. The intraoperative and hospitalization related indicators, such as visual analogue score (VAS score), Constant-Murley shoulder function scores and complications were also collected. The results of average age, return working hours, average hospital days, intraoperative blood loss, surgery time, incision size, average number of perspectives during surgery, VAS score and Constant-Murley shoulder function scores were accepted t test; the results of patient sex, male-female ratio, number of fixed cases of removal and number of complications were performed Chi-square test. Results In this research there were 67 cases, and 65 patients were followed-up for 12 months. In the group T and C, one case missed postoperative visits. Constant-Murley score of group T were as follows: one week (56.3±3.4), two weeks (68.4±4.5), one month (72.1±6.6), three months (78.9±7.2), six months (85.4±7.5) and 12 months(94.1±7.7), Constant-Murley score of group C were as follows: one week(46.3±2.6), two weeks(61.4±3.7), one month(69.8±5.8), three months(77.9±7.0), six months(83.5±7.1) and twelve months(92.2±7.5), and group T were better than that of group C at two weeks after operation, and the difference was statistically significant (F=1.525, P<0.05). The VAS score of group T were as follows: one week(5.60±0.56), two weeks(3.50±0.45), one month(2.90±0.47), three months(1.90±0.51), six months(1.50±0.23)and twelve months(1.20±0.11). The VAS score of group C were as follows: one week(6.50±0.65), two weeks(5.30±0.56), one month(3.10±0.38), three months(2.10±0.57), six months(1.60±0.32) and twelve months(1.30±0.12). The VAS score of group T was better than that of group C at two weeks before operation, and the difference was statistically significant (F=1.549, P<0.05). Conclusion Compared with the traditional clavicular hook plate technique, the technique of minimal incision triple-endobutton has the advantages of small surgical trauma, anatomical reduction of coracoclavicular ligament, easy to control, accelerating recovery of postoperative patients and less complication. Key words: Acromioclavicular joint; Joint dislocation; Athletic injuries

Objective To investigate the clinical efficacy of arthroscopic double Endobutton plate internal fixation in the treatment of acute acromioclavicular joint dislocation. Methods A retrospective case series study was performed to analyze the clinical data of 32 patients with Rockwood type III or V acute acromioclavicular joint dislocation admitted to Foshan Hospital of TCM from May 2015 to February 2018. There were 26 males and six females, aged 22-56 years [(37.7±1.6)years]. There were 22 patients with Rockwood type III and 10 patients with type V. The duration from injury to operation was 2-5 days. All patients were treated with arthroscopic double Endobutton plate internal fixation for coracoclavicular ligament reconstruction. The operation time, hospitalization time, and postoperative shoulder joint braking time were recorded. The shoulder joint function was evaluated by the Constant-Murley score (CMS), visual analogue scale (VAS), American shoulder and elbow surgeons (ASES) score, University of California Los Angeles (UCLA) score and simple shoulder test (SST) before operation and at the last follow-up. Meanwhile, complications such as infection, loosening and joint dislocation were recorded. Results All patients were followed up for 8-48 months [(27.8±11.6)months]. The operation time was 48-93 minutes[(65.0±24.6)minutes], the hospitalization time was 3.2-10 days [(6.5±2.6)days], and the postoperative braking time was 21-35.3 days[(28.2±7.1)days]. All patients had a grade A healing of surgical incision. The VAS was decreased from preoperative (5.7±2.5)points to (1.2±0.8)points at the last follow-up (P<0.01); CMS wasvincreased from preoperative (29.3±3.4)points to (93.2±2.1)points at the last follow-up (P<0.05); ASES score was increased from preoperative (28.9±10.1)points to (95.7±5.6)points at the last follow-up (P<0.05); UCLA score was improved from preoperative (11.6±2.8)points to (34.2±1.5)points at the last follow-up (P<0.05); SST score was improved from preoperative (3.5±1.2)points to (9.7±1.4)points at the last follow-up (P<0.01). The incidence of intraoperative and postoperative complications was 16% (5/32). In two patients, the surgery was changed to U shape fixation circulating the coracoid base due to the coracoidbone tunnel cutting out. One patient was found to have insufficient reduction and received the acromioclavicular joint operation. One patient had reduction loss due to the clavicle button collapsing, and one patient had excessive reduction. Conclusions For Rockwood type III or V acute acromioclavicular dislocation patients, arthroscopic double Endobutton plates for coracoclavicular ligament reconstruction has the advantages of less intraoperative trauma, quick recovery and satisfactory clinical result. However, the incidence of intraoperative and postoperative complications is relatively high, and indications should be strictly controlled. Key words: Acromioclavicular joint; Dislocations; Arthroscopes; Endobutton plates

Background Occurring in almost all age groups, acromioclavicular joint dislocation is a common type of injury in orthopedics with 15-45 years old as the age range with the highest incidence.The core pathological change of acromioclavicular joint dislocation is a rupture ofcoracoclavicular ligament, which in turn causes the instability of acromioclavicular joint and the displacement of distal clavicle relative to acromion.Consequently, a series of clinical symptom is resulted.Clavicular hook plate fixation was used to be applied in the treatment of acromioclavicular joint dislocation. However, there are complications such as the stress fractures of hook plate, the wear of acromion and the loss of reduction after plate removal. Currently, minimally invasive arthroscopyassisted Endobutton fixation has become the prior choice for the treatment of this disease.The key of the procedure is thein-depth understandingofthe anatomy and imaging of trapezoid ligament and conoid ligament. Objective To measure the radiological parameters of coracoclavicular ligament bone tunnel under different fluoroscopic positions in order to provide the anatomic basis for clinical coracoclavicular ligament reconstruction. Methods Twenty-two cadaver specimens of shoulder jointwere used to measure the direction, width of footprint and angle under perspective position of two parts of the coracoclavicular ligament (trapezoid ligamentand conoid ligament) . Results The widths of trapezoid ligament footprint were (26.2±1.2) mm on the clavicle side and (22.7±1.6) mm on the coracoid side.The widths of conoid ligament footprintwere (24.6±1.4) mm on the clavicle side and (19.2±1.6) mm on the coracoid side.Radiological measurementof ligament angulation: the angle between trapezoid ligament and the longitudinal axis of clavicle was (81±4) ° on the anteroposterior view of scapula. Lateral argumentation (83±3) °for trapezoid ligamentand (70±6) ° for conoid ligament. Adjacent relationship with surgical marker: the distances between trapezoid ligament and the midpoint of long axis conoid ligament footprint were (21.9±4.8) mm on the clavicle side and (15.7±1.6) mm on the coracoid side. Conclusion The widths of trapezoid ligament and conoid ligamentfootprints are relatively constant. The angle of trapezoid ligamentinsertion is variable, while the angle of conoid ligament insertion is relatively constant. The anatomic characteristics of coracoclavicularligament can be taken for reference during the anatomic reconstruction of acromioclavicular joint. Key words: Coracoclavicular joint; Trapezoid ligament; Conoid ligament; Reconstruction

Coracoclavicular (CC) ligament augmentation has been a method to treat acromioclavicular (AC) joint dislocation in recent years. The purpose of this paper is to describe our arthroscopic CC ligament augmentation technique in treating type III and V acute AC joint dislocations and to report the early clinical and radiological results. From 2010 to 2011, twelve patients suffering from acute type III or V AC joint dislocations were arthroscopically treated in our department, by CC ligament augmentation after AC joint reduction. The post-operative outcomes were assessed through physical examination, radiographic examination and the Constant-Murley Shoulder Score. All patients post-operatively experienced anatomical reduction in their AC joint dislocation. No intraoperative complications occurred. At a mean follow-up at 24 months (ranging from 18 to 32 months), the mean Constant-Murley Shoulder Score significantly improved from 24.3 pre-operatively to 91.1 post-operatively. No neurovascular complications or secondary degenerative changes of the AC joint were detected in any of the patients. In one case, a second dislocation occurred 1 month post-operation because the patient had had another traumatic injury. This patient accepted a revision operation, but his AC joint eventually fixated into a subluxated position after his second injury. Based on the resultant successful repair in all cases, the arthroscopic CC ligament augmentation method has thus far proven to be a safe and reliable technique for treatment of acute type III or V AC joint dislocation. The arthroscopic CC ligament augmentation with a flip button/polyethylene belt repair is an efficient method to treat acute type III and V AC joint dislocations which should be popularized. IV.

Objective To compare the clinical outcomes of different coracoclavicular ligament (CCL) reconstruction combined with hook plate fixation in the treatment of acromioclavicular joint (ACJ) dislocation of Rookwood type Ⅲ-Ⅴ. Methods A retrospective study was conducted to evaluate the outcomes of 76 patients with ACJ dislocation of Rockwood type Ⅲ-Ⅴ who had been treated with CCL reconstruction using iliotibial tract fascia graft or palmaris longus tendon in addition to hook plate fixation from January 2012 to March 2016. The patients were divided into 2 groups according to their grafts used in CCL reconstruction:group A (39 cases using iliotibial tract fascia graft) and group B (37 cases using palmaris longus tendon iliotibial tract fascia graft). They were firstly treated with CCL reconstruction followed by hook plate fixation. The acromioclavicular and coracoclavicular distances were measured on the postoperative anteroposterior radiographs of the injured shoulders. The outcomes were assessed at the final follow-ups according to Constant-Murley shoulder score and Karlsson criteria. Results The acromioclavicular distances and coracoclavicular distances measured in group A at 12 months after operation were significantly smaller than those measured in group B: (4.7 ± 0.7) mm vs. (5.4 ± 1.3) mm, (7.5 ± 1.5) mm vs. (8.5 ± 1.6) mm, P 0.05). The total incidence of complications in group A and there showed no statistical difference compared with that of group B (P > 0.05). Conclusions In the treatment of ACJ dislocation of Rookwood type Ⅲ-Ⅴ, CCL reconstruction using iliotibial tract fascia graft may lead to better radiographic outcomes than compared with that using palmaris longus tendon, though the 2 grafts lead to similar functional recovery of the injured shoulders. Key words: Acromioclavicular joint; Dislocations; Ligament; Reconstructive surgical procedures