CLINICAL STUDY
Cheek Drooping in 2 Patients With Maxillary Fractures After Rigid Fixation With Bioabsorbable Mesh Seung Hyun Oh, MD,* Chung Hun Kim, MD, PhD,* Hyun Gon Choi, MD,† and Euna Hwang, MD* Abstract: Bioabsorbable plate-screw systems are commonly used for the internal fixation of facial bone fractures. The anterior maxilla has a unique curved shape, and fractured bony fragments tend to be small and fragile; therefore, more effective rigid fixation can be achieved using a molded bioabsorbable mesh rather than a bioabsorbable plate. Herein, we describe 2 patients with cheek drooping after a rigid fixation of comminuted maxillary fracture using bioabsorbable meshes and screws. The postoperative courses were uneventful, but both showed soft tissue bulging in the cheek area of the operation site for 12 to 13 months after the operation. No other symptom or sign related to inflammation or foreign body reaction was noted. In comminuted maxillary fractures, bone fragments are more conveniently fixed with a 1-piece molded bioabsorbable mesh. However, it is believed that a single large mesh may interfere with adhesion between the maxillary surface and the overlying soft tissue. Therefore, we recommend using the least amount of mesh to fixate maxillary bone fragments. Key Words: Cheek drooping, comminuted maxillary fracture, bioabsorbable mesh (J Craniofac Surg 2014;25: 542–543)
B
ioabsorbable fixation systems are commonly used to perform reconstructive procedures in the craniofacial skeleton. These systems are made of degradable copolymers composed of L-lactic acid and D-lactic acid and are degraded in vivo by hydrolysis into α-hydroxy acids that are metabolized in the body. Bioresorption takes place within 2 to 4 years. Such fixation systems have several advantages over metallic plates. They do not interfere with imaging, provide stability to allow effective osteosynthesis, and have great malleability when heated, which allows for easy contouring, especially in application to the curved facial skeleton. Moreover, their biodegradable characteristics eliminate the need to perform secondary operations to remove the plates, especially in growing children.1,2
* Department of Plastic and Reconstructive Surgery, Bundang CHA Medical Center, CHA University, Seongnam; and †Department of Plastic and Reconstructive Surgery, School of Medicine, Konkuk University, Seoul, South Korea. Received June 4, 2013. Accepted for publication December 29, 2013. Address correspondence and reprint requests to Euna Hwang, MD, Department of Plastic and Reconstructive Surgery, Bundang CHA Medical Center, CHA University, 59 Yatap-ro, Bundang-gu, Seongnam, Gyeonggi-do 463-712, South Korea; E-mail: [email protected] The authors report no conflicts of interest. Copyright © 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000697
542
In comminuted maxillary fractures, it is often difficult to perform rigid fixation with plates and screws because the multiple thin bony fragments are prone to break as a result of the drilling and tapping procedures. Because of the unique curvature of the maxilla, molding and precisely contacting a number of bioabsorbable plates to the comminuted bone fragments can be difficult. In contrast, a bioabsorbable mesh is easily molded by heating to 65°C, which allows great ease in contouring according to the anatomic shape of the facial bone. Moreover, surgeons can use multiple holes and fixate the screws at a more proper position on the mesh depending on the placement of the fractured bone segments. There was a report showing that effective and rigid fixation could be achieved through the use of bioabsorbable mesh and screws in comminuted maxillary fractures.3 However, we encountered 2 patients who showed a longstanding cheek drooping after rigid fixation with a bioabsorbable mesh for comminuted maxillary fractures. Herein, we report and discuss this uncommon complication.
MATERIALS AND METHODS Patient 1 A 34-year-old man with a right maxilla and zygoma fracture underwent open reduction and internal fixation through the subciliary and gingivobuccal approach. The incision was deepened to the periosteum. Dissection proceeded to expose the fracture segments, and we cut some portion of a 0.5-mm–thick bioabsorbable mesh (Inion CPS 1.5 mm System; Inion, Tampere, Finland) composed of copolymer of 70% L-lactide, 20% D-lactide, and 10% trimethylene carbonate. The mesh was heated in the water bath (65°C) to be bent to the desired shape fitted to the curvature of the maxilla and cooled down to its configuration (Fig. 1). All fracture sites of the zygoma and maxilla including the zygomaticomaxillary buttress and anterior maxilla were completely covered with a 2.2 2.6-cm piece of molded bioabsorbable mesh. The mesh was fixed with 6-diameter 1.5-mm screws after drilling and tapping. One small bone fragment of the anterior maxilla was reduced and fixed to the undersurface of the mesh
FIGURE 1. Illustration for application of a molded absorbable mesh. The fractured bony fragments are fixed to a mesh using screws.
The Journal of Craniofacial Surgery • Volume 25, Number 2, March 2014
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery • Volume 25, Number 2, March 2014
Cheek Drooping due to Bioabsorbable Mesh
with one 1.5-mm bioabsorbable screw. After saline irrigation, layerby-layer tight closure of the periosteum, muscles, and oral mucosa was completed.
Patient 2 A 12-year-old girl with a right maxilla and zygoma fracture underwent open reduction and internal fixation through a gingivobuccal approach. The incision was deepened to the periosteum. Dissection was done to expose the fracture site. After reducing the displaced maxillary fracture segments, we cut a 2.1 2.4-cm–sized piece of a large 0.5-mm–thick bioabsorbable mesh (Inion CPS 1.5 mm System; Inion, Tampere, Finland) composed of copolymer of 70% L-lactide, 20% D-lactide, and 10% trimethylene carbonate. The mesh piece fit for the fracture site was molded into the shape of the maxillary flexion. The remainder procedures were performed as described in patient 1.
RESULTS Both patients went on to heal satisfactorily and achieve favorable restoration of function. Postoperative computed tomographic scan demonstrated adequate reduction of the fractured maxilla and zygoma (Fig. 2). However, soft tissue bulging occurred on the cheek area of the operative site that produced a drooping cheek appearance, and it did not begin to subside until after 6 to 7 months after surgery (Fig. 3). No symptoms or signs related to inflammation or infection were seen. This cheek drooping was observed similarly in the 2 patients who underwent internal fixation using bioabsorbable mesh that were completely molded along the zygomaticomaxillary buttress and the lower half of the anterior maxilla. We confirmed that the cheek drooping had almost subsided at 12 months after the operation in patient 1 by calling him and having his photograph sent through telephone. Patient 2 showed some improvement, but mild cheek drooping was not completely resolved until 13 months after the surgery.
DISCUSSION The maxilla is a critical bone that provides structural and mechanical support for the midfacial area between the cranial base and the occlusal plane. Because of the thinness of the anterior wall of the maxilla, comminuted maxillary fractures occur frequently, especially in high-velocity injuries. Recent advances in the treatment of facial bone fractures include rigid internal fixation with biodegradable plates and screws or ultrasound-aided fixation using bioabsorbable implant system.4 However, small bone fragments are still difficult to fix with bioabsorbable plates because the plates and screws are larger than the bone fragments. The mesh with smaller holes and shorter
FIGURE 3. Left, Cheek drooping on the right side in patient 1 at 6 months after the surgery. Right, Cheek drooping on the right side in patient 2 at 7 months after the surgery.
distances between the holes enable multipoint screw fixation of small bone fragments. Therefore, rigid fixation using a single mesh is more accurate and stable than that using several plates. Moreover, surgeons can readily make screw holes at any position of the mesh plate. Despite these several advantages, we are reluctant to use a single molded mesh to reconstruct the anterior maxilla because it seems to inhibit contact between the anterolateral surface of the maxilla and the overlying soft tissue. Although multiple small holes in the mesh facilitate contact between the bony surface and the overlying soft tissue, the mesh might act as a barrier to delay or interfere with the adhesion between the underlying bone and the overlying periosteum or soft tissue. For these reasons, cheek drooping was thought to develop from insufficient adhesion between the anterior maxillary surface and the soft tissue around the cheek. Another concern is that small bone fragments may not be able to heal well because of the presence of the barrier, the mesh. Sufficient blood supply and tissue ingrowth to the bone segments from the surrounding soft tissue are essential for the union of small pieces of bone in the comminuted fractures.5 However, it has not yet been confirmed whether the screw holes in the bioabsorbable mesh are sufficient to supply blood flow to the small bone fragments. The bioabsorbable mesh is relatively thin, easily fixated with screws, and convenient to mold and trim. It is very useful in the rigid fixation of comminuted fractures of the maxilla. In addition, a secondary operation to remove the retaining plate is not necessary. On the other hand, the bioabsorbable mesh can be an obstacle to bone union and interrupt adhesion between the underlying bone and the overlying soft tissue. Therefore, we recommend using the least amount of bioabsorbable mesh, consistent with stabile fixation, to minimize the risk for cheek drooping in patients who undergo rigid fixation for comminuted maxillary fractures using a mesh and screws.
REFERENCES
FIGURE 2. Computed tomographic scans showed adequate reduction of maxillary fracture (patient 1). Left, Preoperative coronal view. Right, Postoperative coronal view at 6 months after the surgery.
1. Bell RB, Kindsfater CS. The use of biodegradable plates and screws to stabilize facial fractures. J Oral Maxillofac Surg 2006;64:31–39 2. Pietrzak WS, Eppley BL. An experimental study of heat adaptation of bioabsorbable craniofacial meshes and plates. J Craniofac Surg 2007;18:540–545 3. Shin DH, Kim DJ, Kim SY, et al. Rigid fixation using biomesh type absorbable plate and screws in facial bone fracture. J Korean Soc Plast Reconstr Surg 2010;37:717–720 4. Lee JH, Park JH. The clinical usefulness of ultrasound-aided fixation using an absorbable plate system in patients with zygomatico-maxillary fracture. Arch Plast Surg 2013;40:330–334 5. Anderson H. Current concepts of fracture healing. Clin Orthop Relat Res 1989;249:265–284
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
543
Cheek Drooping in 2 Patients With Maxillary Fractures After Rigid Fixation With Bioabsorbable Mesh Seung Hyun Oh, MD,* Chung Hun Kim, MD, PhD,* Hyun Gon Choi, MD,† and Euna Hwang, MD* Abstract: Bioabsorbable plate-screw systems are commonly used for the internal fixation of facial bone fractures. The anterior maxilla has a unique curved shape, and fractured bony fragments tend to be small and fragile; therefore, more effective rigid fixation can be achieved using a molded bioabsorbable mesh rather than a bioabsorbable plate. Herein, we describe 2 patients with cheek drooping after a rigid fixation of comminuted maxillary fracture using bioabsorbable meshes and screws. The postoperative courses were uneventful, but both showed soft tissue bulging in the cheek area of the operation site for 12 to 13 months after the operation. No other symptom or sign related to inflammation or foreign body reaction was noted. In comminuted maxillary fractures, bone fragments are more conveniently fixed with a 1-piece molded bioabsorbable mesh. However, it is believed that a single large mesh may interfere with adhesion between the maxillary surface and the overlying soft tissue. Therefore, we recommend using the least amount of mesh to fixate maxillary bone fragments. Key Words: Cheek drooping, comminuted maxillary fracture, bioabsorbable mesh (J Craniofac Surg 2014;25: 542–543)
B
ioabsorbable fixation systems are commonly used to perform reconstructive procedures in the craniofacial skeleton. These systems are made of degradable copolymers composed of L-lactic acid and D-lactic acid and are degraded in vivo by hydrolysis into α-hydroxy acids that are metabolized in the body. Bioresorption takes place within 2 to 4 years. Such fixation systems have several advantages over metallic plates. They do not interfere with imaging, provide stability to allow effective osteosynthesis, and have great malleability when heated, which allows for easy contouring, especially in application to the curved facial skeleton. Moreover, their biodegradable characteristics eliminate the need to perform secondary operations to remove the plates, especially in growing children.1,2
* Department of Plastic and Reconstructive Surgery, Bundang CHA Medical Center, CHA University, Seongnam; and †Department of Plastic and Reconstructive Surgery, School of Medicine, Konkuk University, Seoul, South Korea. Received June 4, 2013. Accepted for publication December 29, 2013. Address correspondence and reprint requests to Euna Hwang, MD, Department of Plastic and Reconstructive Surgery, Bundang CHA Medical Center, CHA University, 59 Yatap-ro, Bundang-gu, Seongnam, Gyeonggi-do 463-712, South Korea; E-mail: [email protected] The authors report no conflicts of interest. Copyright © 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000697
542
In comminuted maxillary fractures, it is often difficult to perform rigid fixation with plates and screws because the multiple thin bony fragments are prone to break as a result of the drilling and tapping procedures. Because of the unique curvature of the maxilla, molding and precisely contacting a number of bioabsorbable plates to the comminuted bone fragments can be difficult. In contrast, a bioabsorbable mesh is easily molded by heating to 65°C, which allows great ease in contouring according to the anatomic shape of the facial bone. Moreover, surgeons can use multiple holes and fixate the screws at a more proper position on the mesh depending on the placement of the fractured bone segments. There was a report showing that effective and rigid fixation could be achieved through the use of bioabsorbable mesh and screws in comminuted maxillary fractures.3 However, we encountered 2 patients who showed a longstanding cheek drooping after rigid fixation with a bioabsorbable mesh for comminuted maxillary fractures. Herein, we report and discuss this uncommon complication.
MATERIALS AND METHODS Patient 1 A 34-year-old man with a right maxilla and zygoma fracture underwent open reduction and internal fixation through the subciliary and gingivobuccal approach. The incision was deepened to the periosteum. Dissection proceeded to expose the fracture segments, and we cut some portion of a 0.5-mm–thick bioabsorbable mesh (Inion CPS 1.5 mm System; Inion, Tampere, Finland) composed of copolymer of 70% L-lactide, 20% D-lactide, and 10% trimethylene carbonate. The mesh was heated in the water bath (65°C) to be bent to the desired shape fitted to the curvature of the maxilla and cooled down to its configuration (Fig. 1). All fracture sites of the zygoma and maxilla including the zygomaticomaxillary buttress and anterior maxilla were completely covered with a 2.2 2.6-cm piece of molded bioabsorbable mesh. The mesh was fixed with 6-diameter 1.5-mm screws after drilling and tapping. One small bone fragment of the anterior maxilla was reduced and fixed to the undersurface of the mesh
FIGURE 1. Illustration for application of a molded absorbable mesh. The fractured bony fragments are fixed to a mesh using screws.
The Journal of Craniofacial Surgery • Volume 25, Number 2, March 2014
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery • Volume 25, Number 2, March 2014
Cheek Drooping due to Bioabsorbable Mesh
with one 1.5-mm bioabsorbable screw. After saline irrigation, layerby-layer tight closure of the periosteum, muscles, and oral mucosa was completed.
Patient 2 A 12-year-old girl with a right maxilla and zygoma fracture underwent open reduction and internal fixation through a gingivobuccal approach. The incision was deepened to the periosteum. Dissection was done to expose the fracture site. After reducing the displaced maxillary fracture segments, we cut a 2.1 2.4-cm–sized piece of a large 0.5-mm–thick bioabsorbable mesh (Inion CPS 1.5 mm System; Inion, Tampere, Finland) composed of copolymer of 70% L-lactide, 20% D-lactide, and 10% trimethylene carbonate. The mesh piece fit for the fracture site was molded into the shape of the maxillary flexion. The remainder procedures were performed as described in patient 1.
RESULTS Both patients went on to heal satisfactorily and achieve favorable restoration of function. Postoperative computed tomographic scan demonstrated adequate reduction of the fractured maxilla and zygoma (Fig. 2). However, soft tissue bulging occurred on the cheek area of the operative site that produced a drooping cheek appearance, and it did not begin to subside until after 6 to 7 months after surgery (Fig. 3). No symptoms or signs related to inflammation or infection were seen. This cheek drooping was observed similarly in the 2 patients who underwent internal fixation using bioabsorbable mesh that were completely molded along the zygomaticomaxillary buttress and the lower half of the anterior maxilla. We confirmed that the cheek drooping had almost subsided at 12 months after the operation in patient 1 by calling him and having his photograph sent through telephone. Patient 2 showed some improvement, but mild cheek drooping was not completely resolved until 13 months after the surgery.
DISCUSSION The maxilla is a critical bone that provides structural and mechanical support for the midfacial area between the cranial base and the occlusal plane. Because of the thinness of the anterior wall of the maxilla, comminuted maxillary fractures occur frequently, especially in high-velocity injuries. Recent advances in the treatment of facial bone fractures include rigid internal fixation with biodegradable plates and screws or ultrasound-aided fixation using bioabsorbable implant system.4 However, small bone fragments are still difficult to fix with bioabsorbable plates because the plates and screws are larger than the bone fragments. The mesh with smaller holes and shorter
FIGURE 3. Left, Cheek drooping on the right side in patient 1 at 6 months after the surgery. Right, Cheek drooping on the right side in patient 2 at 7 months after the surgery.
distances between the holes enable multipoint screw fixation of small bone fragments. Therefore, rigid fixation using a single mesh is more accurate and stable than that using several plates. Moreover, surgeons can readily make screw holes at any position of the mesh plate. Despite these several advantages, we are reluctant to use a single molded mesh to reconstruct the anterior maxilla because it seems to inhibit contact between the anterolateral surface of the maxilla and the overlying soft tissue. Although multiple small holes in the mesh facilitate contact between the bony surface and the overlying soft tissue, the mesh might act as a barrier to delay or interfere with the adhesion between the underlying bone and the overlying periosteum or soft tissue. For these reasons, cheek drooping was thought to develop from insufficient adhesion between the anterior maxillary surface and the soft tissue around the cheek. Another concern is that small bone fragments may not be able to heal well because of the presence of the barrier, the mesh. Sufficient blood supply and tissue ingrowth to the bone segments from the surrounding soft tissue are essential for the union of small pieces of bone in the comminuted fractures.5 However, it has not yet been confirmed whether the screw holes in the bioabsorbable mesh are sufficient to supply blood flow to the small bone fragments. The bioabsorbable mesh is relatively thin, easily fixated with screws, and convenient to mold and trim. It is very useful in the rigid fixation of comminuted fractures of the maxilla. In addition, a secondary operation to remove the retaining plate is not necessary. On the other hand, the bioabsorbable mesh can be an obstacle to bone union and interrupt adhesion between the underlying bone and the overlying soft tissue. Therefore, we recommend using the least amount of bioabsorbable mesh, consistent with stabile fixation, to minimize the risk for cheek drooping in patients who undergo rigid fixation for comminuted maxillary fractures using a mesh and screws.
REFERENCES
FIGURE 2. Computed tomographic scans showed adequate reduction of maxillary fracture (patient 1). Left, Preoperative coronal view. Right, Postoperative coronal view at 6 months after the surgery.
1. Bell RB, Kindsfater CS. The use of biodegradable plates and screws to stabilize facial fractures. J Oral Maxillofac Surg 2006;64:31–39 2. Pietrzak WS, Eppley BL. An experimental study of heat adaptation of bioabsorbable craniofacial meshes and plates. J Craniofac Surg 2007;18:540–545 3. Shin DH, Kim DJ, Kim SY, et al. Rigid fixation using biomesh type absorbable plate and screws in facial bone fracture. J Korean Soc Plast Reconstr Surg 2010;37:717–720 4. Lee JH, Park JH. The clinical usefulness of ultrasound-aided fixation using an absorbable plate system in patients with zygomatico-maxillary fracture. Arch Plast Surg 2013;40:330–334 5. Anderson H. Current concepts of fracture healing. Clin Orthop Relat Res 1989;249:265–284
© 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
543
