Pediatr Surg Int (2014) 30:357–359 DOI 10.1007/s00383-013-3323-7
CASE REPORT
Costal osteochondroma spicule associated with pleural effusion James Chen • Scott Nelson • Brian Tzung Harry Applebaum • Daniel A. DeUgarte
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Accepted: 30 April 2013 / Published online: 8 May 2013 Ó Springer-Verlag Berlin Heidelberg 2013
Abstract Costal osteochondromas are a rare cause of lung injury. We report a 7-year-old male who presented with chest pain, cough, and left-sided pleural effusion following a fall. Imaging identified a 2 cm costal osteochondroma, which was resected with a thoracoscopicassisted segmental rib resection. Keywords Costal osteochondroma Hereditary osteochondromatosis Pleural effusion Thoracoscopy Segmental rib resection
Introduction Osteochondromas are bony projections extending from the epiphyseal plate. They develop during bone maturation at the metaphysis in the period from early childhood through the late teens [1]. Osteochondromas typically occur as sporadic, solitary lesions, but may also present as multiple J. Chen S. Nelson B. Tzung H. Applebaum D. A. DeUgarte David Geffen School of Medicine at UCLA, Los Angeles, USA S. Nelson Department of Pathology, UCLA, Los Angeles, USA B. Tzung Renaissance Imaging Medical Associates, Northridge, CA, USA B. Tzung H. Applebaum D. A. DeUgarte Northridge Hospital, Los Angeles, USA H. Applebaum D. A. DeUgarte (&) Division of Pediatric Surgery, Department of Surgery, University of California, 10833 Le Conte Avenue, 709818, Los Angeles, CA 90095-7098, USA e-mail:
[email protected]
lesions as part of a genetic syndrome called hereditary osteochondromatosis (HO), or hereditary multiple exostoses [1]. Patients with HO typically present with multiple osteochondromas of the costal bones (40 %), proximal humerus (50 %), distal femur (70 %), and proximal tibia (70 %) [2]. Although HO is rare with a prevalence of 1 in 50,000 [2], there are a number of reported cases in which HO-related costal osteochondromas have resulted in hemothorax and pneumothorax [1–10]. Here we report the case of a 7-year-old boy with a non-resolving pleural effusion caused by a costal osteochondroma, which was managed with a thoracoscopic-assisted segmental rib resection.
Case presentation A 7-year-old boy presented with a 2 weeks history of chest pain and cough. The symptoms developed a few days following a fall. A chest radiograph and ultrasound demonstrated a pleural effusion of the left lung. In addition, exostoses were noted on the left proximal humerus and the left sixth rib (Fig. 1). Family history revealed that the mother had a history of multiple exostoses suggestive of hereditary osteochondromatosis. Ultrasound-guided thoracentesis was performed, and 150 cc of serosanguineous fluid was aspirated. The effusion recurred the following day. Computed tomography was performed and demonstrated consolidation of the left lower lobe with a moderate pleural effusion. The left sixth rib was noted to have a 2 cm spicule projecting into the thorax (Fig. 2). The contralateral fourth and fifth ribs were found to contain smaller and less-pointed bony projections. A pigtail was placed for continuous drainage and the patient continued to have [50 cc of aspirate per day.
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Fig. 3 Thoracoscopic image of the costal osteochondroma
Fig. 1 Chest radiograph demonstrating osteochondromas of the left proximal humerus and left sixth rib as well as an inadequately drained pleural effusion
Fig. 2 Chest CT demonstrating a spicule of the left sixth rib with persistent pleural effusion
The persistent pleural effusion was attributed to the spicule, and a segmental rib resection was planned. The skin overlying the rib was marked preoperatively with fluoroscopy. The patient was placed in the right, lateral position. A 5 mm trocar was introduced through the site used for the pigtail catheter, and a thoracoscope was used to visualize the osteochondroma. The spicule was covered by inflammatory tissue (Fig. 3) and located on the rib inferior to the marked site. A 4 cm incision was made overlying the affected rib, and a segment of rib containing the spicule was resected (Fig. 4). An intercostal nerve
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Fig. 4 Resected costal segment containing the 2 cm osteochondroma spicule
block was performed, and a chest tube was placed through the trocar site. Histology was consistent with the diagnosis of osteochondroma. The chest tube was removed on postoperative day 2. The patient developed a low-grade fever, which delayed discharge until post-operative day 5.
Discussion Costal osteochondromas are a rare cause of thoracic injury and can result in laceration of the lung, diaphragm, and pericardium [6]. They can present with hemothorax,
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pneumothorax, and a chronic pleural effusion as described in this case report [3]. Osteochondromas are composite bone and cartilaginous projections felt to originate from displacement of physeal cartilage, with subsequent growth at right angles to the long axis of the bone. As they develop, the osteochondroma usually remains in the metaphysis [1]. Microscopically, they are composed of a hyaline cartilaginous cap covered by periosteum. Bone forms deep to the cartilage cap, and it has a direct communication with the medullary canal [10]. Hereditary osteochondromatosis (HO) is an autosomaldominant condition that presents with multiple osteochondromas of the long tubular bones and less frequently on the ribs, pelvis, and vertebrae [1, 6–8, 10]. The condition is also referred to as hereditary multiple exostoses. Linkage analysis has indicated that 70–95 % of patients with HO are found to have mutations in either the EXT 1 or EXT 2 tumor suppressor gene family, with EXT 1 mutations appearing to be more common in males [4, 10]. These mutations are theorized to result in inadequate maturation of chondrocytes into hypertrophic chondrocytes, which contribute to cartilage cap formation observed in osteochondromas in two ways [12]. First, proliferating chondrocytes have increased gene expression of type II collagen when compared to hypertrophic chondrocytes [12]. Secondly, it is theorized that the lack of local chondrocyte signals result in inadequate osteoblast formation [10]. The rate of malignant degeneration of osteochondromas is reported to be 1–6 % amongst patients with HO [10]. Therefore, it is advisable to follow patients with serial radiography. Surveillance is generally considered safe for most asymptomatic costal osteochondromas [5]. The malignant potential is increased amongst osteochondromas along axial sites, such as the ribs, spine, pelvis, and scapula [10]. The post-pubertal period marks a time of significantly reduced bone growth and, therefore, osteochondroma growth. Rapid growth that is noted in an adult indicates an increased malignant potential. Resection is advised for osteochondromas that are symptomatic or rapidly growing, and in adults for those with a cartilage cap thicker than 2.0–3.0 cm [10]. The size of the cartilage cap is variable in children; however, a size [3 cm is suspicious for malignant degeneration [11]. Minimally invasive thoracoscopic techniques are the preferred method for surgical management of patients with symptomatic costal osteochondromas [4, 5, 7–9]. When compared to open thoracotomy, thoracoscopic techniques have shown an overall reduction in complications, shorter recovery periods, reduced post-procedural pain, and
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improved cosmesis [9]. As noted in this case, thoracoscopy can prove invaluable to confirm the location and aid in determining the technique and extent of resection. While negative margins are not necessary for osteochondromas, this case had a relatively broad base, and we felt more confident performing a segmental rib resection to reduce the risk of recurrence. A segmental rib resection is well tolerated and can be performed through a relatively small incision when properly planned using thoracoscopic-guidance. Other groups have reported thoracoscopic-guided resection of the bony projections with a rongeur [4, 8] or shaving of the projection with an arthroscopic burr [4]. Conflict of interest of interest.
The authors declare that they have no conflict
References 1. Stieber JR, Dormans JP (2005) Manifestations of hereditary multiple exostoses. J Am Acad Orthop Surg 13:110–120 2. Schmale GA, Conrad EU, Raskind WH (1994) The natural history of hereditary multiple exostoses. J Bone Jt Surg Am 76(7):986–992 3. Assefa D, Murphy RC, Bergman K, Atlas AB (2011) Three faces of costal exostoses: case series and review of literature. Pediatr Emerg Care 27:1188–1191 4. Mann E, Kaafarani HM, Cassidy C, Chwals WJ, Jackson CC (2011) Spontaneous hemothorax in multiple exostoses: a case report and review of literature. J Laparoendosc Adv Surg Tech 21:575–577. doi:10.1089/lap.2010.0494 5. Khosla A, Parry RL (2010) Costal osteochondroma causing pneumothorax in an adolescent: a case report and review of the literature. J Pediatr Surg 45:2250–2253. doi:10.1016/j.jpedsurg. 2010.06.045 6. Kentaro Imai, Yasuhiro Saga, et al. Pneumothorax caused by costal exostosis. Ann Thorac Cardiovasc Surg, December 26 2012 7. Pham-Duc ML, Reix P, Mure PY et al (2005) Hemothorax: an unusual complication of costal exostosis. J Pediatr Surg 40:e55–e57 8. Alifano M, Morcos M, Molina T et al (2003) An unusual cause of hiccup: costal exostosis. Treatment by video-assisted thoracic surgery. Eur J Cardiothorac Surg 23:1056–1058 9. Oak SN, Parelkar SV, Satishkumar KV et al (2009) Review of video-assisted thoracoscopy in children. J Minim Access Surg 5:57–62 10. GA Schmale, W Wuyts, HA Chansky, WH Raskind (2008) Hereditary Multiple Osteochondromas. Gene Rev 11. Shah ZK, Peh WCG, Wong Y, Shek TWH, Davies AM (2007) Sarcomatous transformation in diaphyseal aclasis. Australas Radiol 51:110–119 12. Pacifici M, Golden EB, Oshima O, Shapiro IM, Leboy PS, Adams SL (1990) Hypertrophic chondrocytes. The terminal stage of differentiation in the chondrogenic cell lineage. Ann N Y Acad Sci 599:45–57
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