Background: Management of high grades of acute acromioclavicular joint dislocation is still a surgical dilemma among the orthopedic surgeons. Many open methods of fixation exist, but the morbidities are frequently high especially in diabetic patients.
Hypothesis: Arthroscopic fixation of acute acromioclavicular dislocation using TightRope device has excellent results with few complications in diabetic patients.
Study design: Case series; level IV.
Methods: A series of twelve diabetic patients with acute acromioclavicular joint dislocation were treated arthroscopically using TightRope device for fixation. The study was conducted between February 2013 and February 2017 at Zagazig University Hospitals. The functional outcomes were assessed using constant score and University of California at Los Angeles shoulder scale. The difference between the mean preoperative and postoperative coraco-clavicular distance was used for radiological assessment. P-value < o.o5 was statistically significant.
Results: All patients were followed up for 24 months. The mean time to return to work was 10.58 ± 1.9 weeks. The mean postoperative constant and (UCLA) score was 92.9 ± 2.9 and 33.08 ± 2.74 respectively. The coraco-clavicular distance was improved from 20.41 ± 2.8 mm preoperatively to 10.91 ± 2.5 mm postoperatively. The p-value was statistically significant < 0.01. There were no cases of infection or wound problems. Only one case had over reduction of the joint.
Conclusion: Arthroscopic assisted fixation of acute (AC) joint dislocation using TightRope device which is safe and minimally invasive technique had satisfactory functional and radiological outcomes with low morbidities in diabetic patients; so, it is strongly recommended for this subgroup of patients.
Keywords: diabetic; minimal invasive; arthroscopic; TightRope
Acromioclavicular (AC) joint dislocation is a common traumatic shoulder insult with male to female ratio of (5:1).4,13 Direct strike to the lateral aspect of the shoulder is the most common mechanism of this injury.17
Rockwood20 classified the (AC) joint disruption into six types according to the direction and the severity. Conservative treatment is indicated in types I and II 21,11,2 ,while surgical treatment is recommended for types IV, V and VI and young active patients with type III. 24,18,26
There are several methods used for fixation like K-wires, hook plate, Bosworth screw, Weaver-Dunn and resection of the lateral end of the clavicle, with no gold standard procedure.26,12,8,23,1,25
Wound healing problems, the need for second operation to remove the hardware, big scar and infection are common complications associated with the traditional open techniques19 particularly in diabetic patients.
An arthroscopic technique using the TightRope device for fixation of acute (AC) joint dislocation which is minimally invasive procedure with little morbidities compared to open techniques has been recently developed.9
This study was conducted because there is no published article discussing the results of arthroscopic assisted fixation of (AC) joint dislocation using TightRope device in diabetic patients.
Our hypothesis was that this safe and minimally invasive technique had excellent functional and radiological results with few complications among diabetic patients.
METHODS
This prospective study was conducted on twelve diabetic patients with acute acromioclavicular joint dislocation (< 3 weeks) at Zagazig University Hospitals between February 2013 and February 2017. All patients were treated with arthroscopic assisted fixation using TightRope system. This study was approved from our university IRB ethical committee.
Patients had chronic dislocation (> 3 weeks), Rockwood type I and II dislocation, (AC) joint arthritis, non-diabetic and patients with associated intra-articular lesions were excluded from this study.
The demographic criteria of the studied group were presented in (Table 1).
Table (1): The demographic characteristics of the studied patients*
Age (years)
Mean 44.3
Range 35-52
Sex
Male 10 (83.3%)
Female 2 (16.6%)
Injured side
Right 9 (75%)
Left 3 (25%)
Type of injury
Type III 7 (58.3%)
Type V 5 (41.6%)
Mechanism of injury
Motor cycle 4 (33.3%)
Motor vehicle 3 (25%)
Pedestrian 3 (25%)
Falling from stairs 2 (16.6%)
*Data are presented as number (n) and percentage (%)
Surgical Technique
All patients had controlled blood glucose level and given antibiotic one hour preoperatively. Under general anesthesia, the patient was positioned in beach-chair position. Three arthroscopic portals were used in this technique (Figure 1A). Diagnostic arthroscopy of the shoulder was done through the standard posterior portal to detect other gleno humeral joint lesions. The antero-superior and antero-inferior portals were done using spinal needle from outside in. The rotator interval was released exposing coracoid process. The arthroscope was switched to the antero-superior portal for better viewing the base of coracoid process.
The under-surface of the coracoid process was released using electro cautery device from the antero-inferior portal. Closed reduction and temporary K-wire fixation under image intensifier from the lateral border of the acromion was done.
The tip of AC TightRope drill guide was centered under base of coracoid process through antero-inferior portal. The top of the drill guide was positioned over the lateral end of the clavicle where 1.5 cm skin incision was done down to the bone. The top of the guide system was positioned at the center of the superior surface of the clavicle. A 2.4 mm guide pin was drilled from the clavicle to base of the coracoid under direct vision until the tip of the pin penetrates the inferior cortex of the coracoid.
A 4 mm cannulated drill was passed over guide pin under direct vision till it came out of the inferior surface of the coracoid (Figure 1B).
The guide pin was removed leaving the drill in place, the nitinol wire was passed through the cannulated drill and taken out through the antero-inferior portal by a grasper leaving the suture loop superiorly and the drill was removed. The traction suture of the TightRope was passed through suture loop; traction was done until the button was flipped under the inferior surface of the coracoid (Figure 1C). The TightRope was tightened, the K-wires were removed from the lateral border of the acromion and final tightening and tying of the TightRope suture was done under image intensifier to check the reduction. The wound was closed in layers.
Figure 1. (A) Pre-operative picture of the left shoulder showing skin landmarks and portals. (B) Intra-operative image showing the cannulated drill came out of the under surface of the coracoid. (C) The button of the TightRope flipped on the inferior surface of the coracoid process.
Postoperative Management
All patients were discharged from the hospital within 24 hours after surgery. Antibiotic was given intravenously for 3 days only. Arm sling with immobilizer was worn for 6 weeks, elbow flexion-extension was allowed but no shoulder flexion-abduction. Full active range of motion of the shoulder was allowed after 6 weeks. Heavy strenuous activity was not permitted till 3 months postoperative.
Follow-up
Clinical follow up
Wound healing problems or infection were documented, also postoperative means of constant score and University of California at Los Angles shoulder scale were recorded at the end of the follow-up period.
Radiological follow up
Postoperative X-ray was taken at 0, 6 weeks, 3 months, 12 months and 24 months (Figure 2). The coraco-clavicular distance before and after surgery was recorded.
Figure 2. (A) Pre-operative radiograph of the left shoulder shows Rockwood type V dislocation. Post-operative x-rays after reduction and fixation with TightRope were taken at 0 (B) and at 6 months (C).
Statistical Analysis
The results were presented as mean ± standard deviation. Paired t-test was used to compare the means of coraco-clavicular distance before and after surgery. P-value < 0.05 was considered statistically significant.
RESULTS
All patients were followed up for 24 months, with no patient was lost during the follow-up period. The main causes of injury were motor cycle (33.3%), motor vehicle (25%) and pedestrian injuries (25%). The most common type of injury was type III (58.3%). The mean time interval between injury and surgery was 8.25 ± 4.4 (range, 3-19 days).
The mean time to return to work was 10.58 ± 1.9(range, 8-14 weeks). The mean postoperative (UCLA) scale was 33.08 ± 2.74 (range, 27-35), while the mean postoperative constant score was 92.9 ± 2.9 (range, 88-98). The coraco-clavicular distance was improved from 20.41 ± 2.8 mm preoperatively to 10.91 ± 2.5 mm postoperatively with p-value < 0.01 which was statistically significant (Table 2).
There were no intraoperative complications like fracture clavicle or fracture of the coracoid process. There was no patient encountered wound complication or infection. There was no need to remove the implant in any patient.
Only one patient had over correction of the (AC) joint due to over tightening of the TightRope sutures, but this patient had satisfactory functional results without any complaint at the end of the follow up (Figure 3).
Figure 3. Post-operative x-ray shows over reduction of the (AC) joint.
Table (2): The results at the end of follow-up period*
Time interval from injury to surgery (days)
8.85 ±4.4(3-19)
Time to return to work (weeks)
10.58 ± 1.9(8-14)
Mean postoperative (UCLA) scale
33.08 ± 2.7(27-35)
Mean postoperative constant score
92.9 ± 2.9(88-98)
(CC) distance (mm)
Preoperative
20.41 ± 2.8(17-25)
Postoperative 10.91 ± 2.5(4-14)
*The results are presented as mean ± standard deviation.
(UCLA), University of California at Los Angeles shoulder scale.
(CC), Coraco-Clavicular distance.
DISCUSSION
Surgical treatment of acute (AC) joint disruption is still controversial among the orthopedic surgeons.3 Several methods of fixation were utilized such as K-wires, hook plate and coraco-clavicular screws.
Many drawbacks were encountered with these techniques like K-wire migration and breakage. The increased risk of infection, shoulder stiffness, big scar and the need of second procedure for implant extraction were common complications with hook plate. Also coraco-clavicular screw failure and subluxation after its removal.22, 16, 7
The recently developed arthroscopic fixation of (AC) joint dislocation using TightRope device had the following advantages: minimal risk of stiffness, less infection, detection of associated shoulder lesions, short hospital stay, less wound healing problems and no surgery is required to remove the implant 14, so this technique is considered safe and more suitable for diabetic patients.
The rationale of this procedure is to maintain the joint reduced during the initial phase of healing (< 3 weeks) to permit healing of coraco-clavicular ligament, acromioclavicular capsule and the deltotrapezial fascia.15
A previous study was conducted on ten patients with acute (AC) joint dislocation fixed arthroscopically by TightRope, the mean postoperative constant score was 96.3 and all patients had satisfactory clinical and radiological results except in one case due to technical intraoperative error.6
Seventeen patients with acute (AC) joint disruption were operated by Chaudhary et al.5 using TightRope device. The mean postoperative constant score was 86.4, the mean time to return to work was 4 months and the (CC) distance decreased from 21.5 mm preoperatively to 9.8 mm postoperatively with only one case failure.
Gupta et al.10 performed a study on ten patients with acute (AC) joint dislocation. The mean postoperative score was 92.2 and satisfactory reduction was achieved in all cases. Although the previous studies were conducted on non-diabetic patients, but the results of our study were similar to the aforementioned studies. In our study, the mean postoperative constant score was 92.9, the mean time to return to work was 10.58 weeks and the (CC) distance decreased from 20.41 mm preoperatively to 10.91 mm postoperatively.
All patients had satisfactory functional and radiological results. There were no cases of infection or failure. There was only one case had over reduction of the (AC) joint due to over tightening of the TightRope sutures with no functional deficit. The hypothesis in our study was achieved.
The limitations of this study were as follow: it was done on small number of patients, it was a short term study that needs long term follow up to detect (AC) joint arthritis and there was no control group to compare the results of this technique with other methods of fixation.
In conclusion, our study demonstrates that arthroscopic assisted fixation of acute (AC) joint disruption using TightRope is safe and minimally invasive procedure with satisfactory functional outcomes and low morbidities in diabetic patients.