We thank Dr. Ibrahim for his interest in our recent article(1) and we would like to make the following comments in response:

This is an interesting and accurate remark. However, as seen in other parts of the developing skeleton, an injury to the lateral clavicle and the acromioclavicular area is more likely to be a physeal fracture than a true acromioclavicular separation(2,3). Prior to epiphyseal closure, the physis is weaker than the ligaments and this is the main reason that, following an injury, the ligaments usually remain intact while the bone is fractured(4,5). This, of course, does not mean that ligaments are not injured at all, even though they (usually) do remain intact. We believe that this principle is applied in our case as well (i.e. the acromioclavicular joint had also suffered an injury even though "intraoperative findings revealed an intact acromioclavicular joint"). Furthermore, this terminology (i.e. acromioclavicular joint injury) seems to be strongly supported by the literature(2,3,6), it was used by Eidman et al.(3) when this type of injury was reported for the first time and probably is one of the reasons that Dameron and Rockwood (2,6) have included in their well established classification of acromioclavicular injuries, types of injuries that are not true acromioclavicular separations.

We totally agree with Dr. Ibrahim regarding his second comment. In fact, we are also familiar with at least one unpublished case of a Kirschner Wire (KW) migration following a clavicle fixation that took place at our department. Nevertheless, we believe that KW fixation remains a reliable and safe technique(especially in the developing skeleton). Ever since we began bending the exterior part of the KW, ie. the part left out of the patient’s skin, no such incident has occurred.

References:

1. Kirkos JM, Papavasiliou KA, Sarris IK, Kapetanos GA. A rare acromioclavicular joint injury in a twelve-year-old boy. A case report. J Bone Joint Surg Am 2007;89:2504-2507.

2. Tachdjian MO. Upper extremity injuries. In: Herring JA, editor. Pediatric Orthopedics, 3rd edition. Philadelphia: W.B. Saunders Company; 2002. p 2115-39.

3. Eidman DK, Siff SJ, Tullos HS. Acromioclavicular lesions in children. Am J Sports Med 1981;9(3):150-4.

4. Havranek P. Injuries of distal clavicular physis in children. J Pediatr Orthop 1989;9(2):213-5.

5. Montgomery SP, Loyd DL. Avulsion fracture of the coracoid epiphysis with acromioclavicular separation. Report of two cases in adolescents and review of the literature. J Bone Joint Surg Am 1977;59- A:963-5.

6. Dameron TB Jr, Rockwood CA Jr. Fractures and dislocations of the shoulder. In: Rockwood CA Jr., Wilkins KE, King RE editors. Fractures in Children. Philadelphia: J.B. Lippincott Company; 1984. Vol 3, p 628.

To The Editor:

I read with interest the article, "A Rare Acromioclavicular Joint Injury in a Twelve-Year-Old boy. A Case Report(1) and I would offer the following comments:

The title acromioclavicular joint injury is not appropriate as the "intraoperative findings revealed an intact acromioclavicular joint".

I would caution against using Kirschner wires for fracture fixation because there have been numerous reports in the literature of Kirschner wires migrating from the clavicle(2-7).

The author did not receive any outside funding or grants in support of his research for or preparation of this work. Neither he nor a member of his immediate family received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, division, center, clinical practice, or other charitable or nonprofit organization with which the author, or a member of his immediate family, is affiliated or associated .

References:

1. Kirkos JM, Papavasiliou KA, Sarris IK, Kapetanos GA. A rare acromioclavicular joint injury in a twelve-year-old boy. A case report. J Bone Joint Surg Am. 2007;89:2504-2507.

2. KK Tan, S Ibrahim. Kirschner Wire Migration to the Cervical Spine: A Complication of Clavicular Fixation in a Child. Malaysian Orthop J. 2007;1(1):45-6

3. Nordback I, Markulla H. Migration of Kirschner pin from clavicle into ascending aorta. Acta Chir Scand. 1985;151:177-9.

4. Leppilahti J, Jalovaara P. Migration of Kirschner wires following fixation of the clavicle-a report of 2 cases. Acta Orthop Scand. 1999; 70(5):517-26.

5. Regel JP, Pospiech J, Aalders TA, Ruchholtz S. Intraspinal migration of a Kirschner wire 3 months after clavicular fracture fixation. Neurosurg Rev. 2002;25:110-2.

6. Fransen P, Bourgeois S, Rommens J.Kirschner wire migration causing spinal cord injury one year after internal fixation of a clavicle fracture. Acta Orthop Belg. 2007 Jun;73(3):390-2.

7. Nishizaki K, Seki T. Intracardiac migration of a Kirschner wire from the right clavicle. Asian Cardiovasc Thorac Ann. 2007 Jun;15(3):272-3.