|Year : 2015 | Volume
| Issue : 1 | Page : 50-53
Clinical outcomes of hook-plate fixation in the treatment of unstable distal clavicular fractures and acromioclavicular joint dislocations
Naif M Alhamam1, Isam H Bella2, Fares Z Uddin3, Munirah A Al-Afaleq2, Sarah A Al-Afaleq4, Fahad K Al-Khalifa2
1 Department of Orthopedic Surgery, King Faisal University, Al-Ahsa, Saudi Arabia
2 Department of Orthopedic Surgery, Bahrain Defence Force Hospital, Bahrain, Bahrain
3 Department of Orthopedic Surgery, King Hamad University Hospital, Bahrain, Bahrain
4 Department of Orthopedic Surgery, College of Medicine, Arabian Gulf University, Bahrain, Bahrain
|Date of Web Publication||20-Jan-2015|
Naif M Alhamam
King Faisal University, P.O. Box 1625, Al-Ahsa 31982
Background: Presented here is a case series assessing the outcomes following hook-plate fixation in patients with acute unstable (Neer type 2) fractures of the distal clavicle and acute acromioclavicular (AC) joint dislocations .
Materials and Methods: A total of 38 patients fit the criteria of our retrospective study. The ages of the patients ranged from 17 to 50 years (mean of 28 years). Twenty-one patients had AC joint dislocations, whereas 17 had unstable distal clavicular fractures. The average follow-up period was 18 months (period from 13 to 23 months). Subjective shoulder scores (Constant Shoulder Score, Oxford Shoulder Score) were assessed along with radiological images.
Results: No early complications, iatrogenic fractures, acromial osteolysis or other complications were found. The average constant score was 92.4 (range of 85-100); the difference between normal and abnormal sides was found to be <11, whereas the mean Oxford Score was 45 (ranging from 40 to 48).
Conclusion: Hook-plate fixation is an invaluable method of stabilizing acute unstable distal clavicular fractures and AC joint dislocations, resulting in high union rates and restoration of shoulder function.
هذه دراسة استرجاعية لسلسلة من الحالات لتقييم عملية تثبيت لوحة هوك عند المرضى المصابين بكسور عظمة الترقوة الحاد غير المستقر وكذلك خلع المفصل الأخرمي. وشملت الدراسة 83 مريضًا، 12 منهم يعانون من خلع المفصل الأخرمي و 71 مريضًا من كسور عظمة الترقوة الحاد غير المستقر. تمت متابعة هذه الحالات لمدة 81 شهرًا بصور الأشعة. ووضحت النتائج عدم حدوث مضاعفات أو كسور بسب المعالجة أو تحلل العظام الطرفية. خلصت الدراسة إلى أن عملية تثبيت لوحة هوك تمثل طريقة ممتازة لتثبيت كسور عظمة الترقوة الحادة وخلع المفصل الأخرمي وتؤدي إلى معدلات التحام عالية واسترداد وظيفة الكتف.
Keywords: Acromioclavicular, arbeitsgemeinschaft fόr osteosynthesefragen, clavicle, hook-plate
|How to cite this article:|
Alhamam NM, Bella IH, Uddin FZ, Al-Afaleq MA, Al-Afaleq SA, Al-Khalifa FK. Clinical outcomes of hook-plate fixation in the treatment of unstable distal clavicular fractures and acromioclavicular joint dislocations. Saudi J Med Med Sci 2015;3:50-3
|How to cite this URL:|
Alhamam NM, Bella IH, Uddin FZ, Al-Afaleq MA, Al-Afaleq SA, Al-Khalifa FK. Clinical outcomes of hook-plate fixation in the treatment of unstable distal clavicular fractures and acromioclavicular joint dislocations. Saudi J Med Med Sci [serial online] 2015 [cited 2019 Jun 25];3:50-3. Available from: http://www.sjmms.net/text.asp?2015/3/1/50/149679
| Introduction|| |
Unstable fractures of the distal clavicle and acromioclavicular (AC) joint dislocations are a clinical problem. The original classification by Neer in the 1960s described two types of distal clavicular fractures: Type I in which the coracoclavicular ligaments remain intact, and type II in which the coracoclavicular ligaments are torn from the medial fragment (only the trapezoid ligament remains attached to the lateral fragment).  This classification was later revised to include type III fractures which involved extension into the AC joint; type IV fractures which are seen in children and involve a disruption of the periosteal sleeve and type V, which involve an avulsion of the ligaments with a small inferior cortical fragment. 
Acromioclavicular joint injuries are classified most commonly using the 6-grade system described by Rockwood et al. (a modification to the earlier 3-type classification system described by Allman  and Tossy et al. ). It takes into account not only the AC joint itself, but also the coracoclavicular ligament, the deltoid and trapezius muscles and the direction of the dislocation of the clavicle with respect to the acromion. Types IV, V, and VI are unstable and therefore, mandate early surgical reduction and fixation. Conservative management of these injuries can lead to deleterious consequences such as joint arthritis. The debate on the most appropriate method of management of these injuries ranges with the recommendation of open reduction and internal fixation as a first choice of treatment by some, while others are strong in their advocacy of conservative treatment. Here, we report our experience of using the hook-plate [Figure 1] in the treatment of unstable distal clavicular fractures.
The aim of this study was to assess the outcomes of the AO clavicular hook-plate in the management of unstable distal clavicular fractures and AC joint dislocations.
|Figure 1: Right acromiclavicular fracture dislocation fixed with hook plate.|
Click here to view
| Materials and methods|| |
All clavicular injuries utilizing the AO hook-plate that were used in operations in the Bahrain Defense Force Hospital from 2005 to 2011 were identified. Thirty-eight patients (37 males and one female) whose ages ranged from 17 to 50 years (mean of 28 years) were included in the study. Twenty-one suffered AC joint dislocations, whereas 17 had unstable distal clavicular fractures. All injuries were acute and operated on between 2005 and 2011. Healing and complications of the procedure were assessed retrospectively from case records and radiographs. The Constant Shoulder Score and the Oxford Score [Table 1] and [Table 2] (subjective questionnaires) were then assessed during a scheduled clinical follow-up.
| Results|| |
All injuries healed by first intention without complications such as recurrent AC subluxations/ dislocations, infection or frozen shoulder. Loosening of the implant was identified and all patients were put on follow-up for an average of 18 months. X-ray analysis demonstrated that the bony union was achieved in all patients after 3-6 months with a mean healing duration of 3.9 months. The mean Oxford Score was 45 (range of 40-48) and the mean Constant Shoulder Score was 92.4 (range of 85-100). The difference of the Constant Shoulder score between the normal and abnormal sides was <11. No restrictions of the range of motion were found in any of the subjects.
| Discussion|| |
There are several well-described methods for the management of displaced distal clavicle fractures and AC dislocations. K-wiring tension band wiring, coraco-clavicular screw, direct plate fixation and conservative management were few. The AO hook-plate fixation has resulted in an excellent union rate, no limitations of shoulder function and overall patient satisfaction. ,,
Fractures of the distal end of the clavicle represent over 20% of clavicular fractures. , They are associated with a high rate of non-union and delayed union after conservative management.  Conservative management has been extensively studied. Nordqvist et al. reported ten non-unions in 23 patients with type 2 fractures after conservative treatment. Eight of these were asymptomatic; no patient had severe residual shoulder dysfunction. The authors recommended that short-term sling immobilization can be used to treat Neer type 2 fractures of the distal clavicle. They did not objectively assess shoulder function. Neer et al. found a non-union rate of 50% using conservative methods. On the other hand, a study of 43 patients with type 2 fractures conservatively managed, found a much higher incidence of local complications, residual shoulder dysfunction and non-unions.  They recommended open reduction and internal fixation as the treatment of choice.
The complication rates following K-wire fixation are controversial with reported high rates of wire migration. , Migration after Knowles pin fixation is less common, but the pin violates the AC joint. This can lead to the development of osteoarthritis.  Hackenberger et al. in 2004  studied 28 shoulders after hook-plate fixation using magnetic resonance imaging and ultrasonography. They found no rotator cuff lesions or signs of impingement. Although several authors have reported a high rate of non-union, pain and shoulder dysfunction with conservative treatment, the need for operative treatment of Neer type 2 fractures is still debatable. The retrospective comparative study by Edwards et al. suggested that a non-surgical treatment leads to non-union in one-third of cases and delayed union in half of all cases. Local complications such as shoulder dysfunction were more common after conservative management than after an operation. In contrast, Robinson et al. recommended non-operative treatment of patients older than 35 years. A retrospective study of 30 patients also came to the same conclusion and suggested that surgical treatment was unnecessary. 
Our study reinforces the clinical application of the AO hook-plate in the treatment of unstable distal clavicular fracture and AC joint dislocations. We demonstrated ideal function and union which was evident both clinically and radiologically. In our technique of fixation, an AO plate was applied on the superior part of the clavicle and the hook passed below the acromion, posterior to the AC joint thereby not disrupting the joint and allowing the ligaments to heal.
No early complications were found such as infection, soft tissue problems, non-union, delayed union, calcification of the coracoclavicular ligaments or AC joint discrepancies (diastasis of the AC joint and re-dislocation of the AC joint).
| Conclusion|| |
Arbeitsgemeinschaft für osteosynthesefragen (AO) hook-plate fixation of unstable lateral clavicle fractures and AC joint dislocations resulted in an accelerated rate of union. The principal advantages of this method are anatomical reduction and early rehabilitation leading to satisfactory healing and excellent shoulder girdle function.
Based on our results, this is a reliable method which restores shoulder function and improves patient outcomes.
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[Table 1], [Table 2]