radiologic evaluation of internal fixation devicesin the

Pictorial essay

Rev. Argent. Radiol. 2017;81(4): 285-295 285

Abstract Treatment of bone fractures of the upper limb can be performed by closed oropen methods. Closed methods are based on the principle of immobilization and / or tractionwith external materials. Instead, open surgical methods use elements of internal or externalfixation. X-rays continue to be the method of choice for postoperative evaluation of these devices. Basic knowledge of the ma-terials used is necessary for a good assessment and medical report.© 2017 Sociedad Argentina de Radiología. Published by Elsevier Spain, S.L.U. This is an openaccess article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Keywords: Fractures; Bones; Fixation; Prostheses; X-Rays.

IntroductionSurgical fixation devices used in the appendicular skeleton are evaluated by various diagnostic imaging methods. These devices, designed to treat bone fractures or deformities, are made of surgical stainless steel, titanium, different alloys and/or biodegradable materials. In the immediate postoperative examination and subsequent follow-up in asymptomatic pa-tients, the position, structure and relationship with bone of these devices should be evaluated.X-rays continue to be the method of choice when compared to other more complex methods. However, computed to-mography (CT) may be used for mid- and long-term follow-up as the method of second choiceand magnetic resonance imaging (MRI) may be used for the evaluation of resorbable or biodegradable devices. Complicated postsurgical cases require a multi-method approach (X-ray, CT, MRI and ultra-sound)1-3.We provide pictures of x-rays with a great variability and loca-tion of surgical devices used in upper limbs.

Treatment of fractures

In individuals with trauma and fracture the initial purpose is to provide the least invasive treatment, implementing closed reduction, bone alignment restoration and stabilization with traction or external compressiondevices (blade plates or casts).

Thus, the goal is to achieve early recovery by means of external callus formation, which is stimulated by muscle dynamization, joint movement and load transfer. Mechanical structural sta-bility is achieved between weeks 6 and 18. After this period, repair continues with bone marrow remodeling1,4,5.However, in some cases surgical fixation with reduction of fragments is indicated. The goal is to preserve bone and soft tissue blood flowusing the least traumatic technique to allow rapid healing and restoration of limb function and motion5,6.In recent years, the idea of achieving reduction in a man-ner as physiological as possible has prevailed over a visually perfect alignment, giving more importance to functional mo-tion5,6 (table 1).Limb fracture treatment may be performed using closed or open methods. Closed methods use reduction, stabilization and immobilization with casting; and less frequently skin or skeletal traction. Open methods, instead, use surgical reduc-tion with internal fixation and stabilization using internal fixa-tion devices. These methods are superior in providing a high degree of mechanical stability, with their disadvantage being the associated surgical trauma1,5.

Surgical devices

Internal fixation devices provide a rigid structurethat limits movement between bone fragments preventing the forma-tion of an external callus. The device should form a whole

Radiologic Evaluation of Internal Fixation Devicesin the Upper LimbE. Rombolá

Preventive Imaging Department, Investigaciones Médicas, Ciudad Autónoma de Buenos Aires, Argentina

Rev. Argent. Radiol. 2017;81(1): 285-295

Radiologic Evaluation of Internal Fixation Devicesin the Upper Limb

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unit with the injured bone to resist the stress caused by physi-ological activity.Devices function on biomechanical principles of fragmentary compression, bridging and internal immobi-lization.From their origin to the present, more and better devices have been developed. They can be used alone or in combina-tion: collars (washers), staples, pins, wires, screws, plates and intramedullary nails2,4,7,8 (fig. 1; table 2).

Choosing devices according to the bone involved

In glenoid cavity, anchoring and fixation devices (screws) are used for reinsertion of the labrum or tendons (figs. 2 and 3), while in the clavicle, plates (neutralization and support) and screws are used3,6 (fig. 4).As regards the humerus, anchoring devices are used for ten-

Table 1: Scheme of the algorithm for the treatment of fractures.

Fracture treatment

Closed Open

Inmobilization Traction External Internal fixation fixation

Cast Skin traction FIXATORS INTERNAL FIXATION Blade plate Skeletal traction Uniplanar fixator Staples and washers Ring fixator Pins Hybrid fixator Wires Screws Plates Intramedullary nails

Table 2: Fixation devices and their function.

Device Function

Washers -Provide additional surface over the fixation screw, preventing breakage of cortical bone. - Fixation of avulsed tendonsStaples - Fixation of arthrodesis and corrective osteotomiesPins - Guides for placement of screws - Traction and temporary or definitive external / internal fixationWires - Fixation for cerclage and tension bands - Cerclage wires and tension bandsScrews - Fixation of plates to the bone - Compression between two fragments - Anchoring of ligaments, tendons or capsules - Cortical bone or cancellous bone screw, cannulated with thread and/or wirePlates - Dynamic compression, neutralization and supportIntramedullary nails - Immobilization in highly unstable comminuted fractures with substantial soft tissue involvement - Consolidation by periosteal callus formation


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don reinsertion, humeral head replacement prosthesis, in-tramedullary nails for diaphysis and plates with screws for diaphysis or distal end3,6,8 (figs. 5-7).In the ulna, olecranon fractures are usually treated with long fixation pins and tension bands (wires), but specially designed plates may also be placed3,6,8 (figs. 8-10).For radial head fracture, dedicated prosthesis may be used (fig. 11), while radial and ulnar shaft fracturesare treated with

compression and neutralization plates3,6,8 (figs. 12 and 13). For the distal radius, specially designed angled plates and/or pins are used3,6,8 (figs. 14 and 15).For carpal bones, various types of screws may be used (threaded cannulated cortical or cancellous bone) for frag-mentary compression and attachment of ligaments or joint capsule6,8 (figs. 16 and 17). For metacarpal and phalangeal bones, threaded or unthreaded pins are used8 (figs. 18-22).

Figure 1. Picture of some of the devices used: washers, sta-ples, pins, wires, screws, plates, prostheses and intramedul-lary nails.

Figure 2. Front X-ray of the right shoulder with anchor screw for glenoid labrum and glenohumeral ligaments attachment.

Figure 3. Front X-ray of the left shoulder with anchor screw for supraspinous tendon attachment.

Figure 4. Front X-ray of the right shoulder with plate and screws over the clavicle and functionality based on three bio-mechanical principles: dynamic compression, neutralization and support.



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Figure 5. X-ray of the right shoulder with total humeral pros-thesis in (a) arm abduction and (b) neutral position.

b

a

Figure 6. Front X-ray of the right arm with rigid intramedullary screw and proximal dynamic block (screw) for dis-placed fracture of the humeral shaft

Figure 7. Front X-ray of the right arm with plate and screws for non-dis-placed fracture of the hu-meral shaft.

Figure 8. X-ray of the right elbow with reconstruction plate and screws for multifragmentary distal humerus fracture: (a) front view and (b) lateral view.

a b


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Figure 9. X-ray of the left elbow with low-impact dy-namic compression plate and holes between screws to minimize compression damage in the periosteum and favor circulation; (a) front view and (b) lateral view.

a b

Figure 10. X-ray of the left elbow: olecranon fracture fixed with Kirschner wires and pins in (a) front view and (b) lateral view.

a b



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Figure 11. X-ray of the right elbow with total radial head prosthesis and anchor screw in (a) front view and (b) lateral view.

a b

a b

Figure 12. X-ray of the right forearm with radial shaft fracture treated with dynamic compression plate and screws; (a) front view and (b) lateral view.

Figure 13. Front X-ray of the left forearm with radial and ul-nar shaft fracture. Dynamic compression plate with screws and wire in the radius. Two dynamic compression plates with screws were placed in the ulna.


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a b

Figure 14. X-ray of the left wrist with specially designed plate (T-plate) and screws for radial fracture with joint involvement; (a) front view and (b) lateral view.

Figure 15. Front X-ray of the right wrist with smooth and spade-point (Kirschner) wire in the radial styloid process.

a b

Figure 16. X-ray of the right wrist with cannulated cancellous bone screw for scaphoid: (a) front view and (b) lateral view.



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a b

Figure 17l (a) Front and (b) lateral X-ray of the right wrist: ring-type fixation devices for carpal bones.

Figure 18. Front X-ray of the right wrist with pins for treating fractures of the shaft of the fourth and fifth metacarpal bones.

Figure 19. Front X-ray of the left wrist with pin in the fifth metacarpal bone.


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Figure 22. X-ray of the fourth finger with pins in the phalanges; (a) front view and (b) lateral view.

Figure 20. Front X-ray of the left hand with low-impact dy-namic compression plate, designed for the fourth metacar-pal bone, with screws.

Figure 21. Front X-ray of the right hand with intramedullary screws, designed with threads on both ends (Herbert), in the proximal pha-lanx of the second and third fingers.

a b



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Confidentiality of dataThe authors declare that they have followed the protocols of their work center on the publication of patient data and that all the patients included in the study have received suf-ficient information and have provided their written informed consent.

Conflicts of interestThe author declares as a possible conflict of interest being an editor of the Musculoskeletal section for Revista Argentina de Radiología.

References1. Taljanovic MS, Jones MD, Ruth JT, Benjamin JD, Sheppard JE, Hunter TB.

Fracture fixation. Radiographics. 2003;23:1569---90.2. Hunter TB, Taljanovic MS. Glossary of medical devices and procedures: ab-

breviations, acronyms, and definitions. Radiographics. 2003;23:195---213.3. Beaman FD, Bancroft LW, Peterson JJ, Kransdorf MJ, Menke DM, DeO-

rio JK. Imaging characteristics of bone graft materials. Radiographics. 2006;26:373---88.

4. Parikh SN. Bone grafts substitutes in modern orthopedics. Orthopedics. 2002;25:1301---11.

5. García C, Ortega DT. Elementos de osteosíntesis de uso habitual en frac-turas del esqueleto apendicular: evaluación radiológica. Rev Chil Radiol. 2005;11:58---70.

6. Richardson ML, Kilcoyne RF, May KA, Lamont JG, Hastru WP. Radio-graphic evaluation of modern orthopedic fixation devices. Radiographics. 1987;7:685---701.

7. Slone RM, Heare MM, Vander Griend RA, Montgomery WJ. Orthopedic fixation devices. Radiographics. 1991;11:823---47.

8. Taljanovic MS, Hunter TB, Miller MD, Sheppard JE. Gallery of medical devices. Part 1: orthopedic devices for the extremities and pelvis. Radio-graphics. 2005;25:859---70.

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