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Multiple osteocartilaginous exostoses of the lower extremity: A case report
The Foot 25 (2015) 62–65
Contents lists available at ScienceDirect
The Foot journal homepage: www.elsevier.com/locate/foot
Case report
Multiple osteocartilaginous exostoses of the lower extremity: A case report Garry Shtofmakher ∗ , Michelle A. Kaufman, Prashant H. Bhoola, Ankur A. Patel, Susan M. Rice, Randy E. Cohen New York College of Podiatric Medicine, 53 East 124th Street, New York, NY 10035, United States
a r t i c l e
i n f o
Article history: Received 5 October 2014 Received in revised form 8 November 2014 Accepted 28 November 2014 Keywords: Multiple hereditary osteochrondromatosis Osteochondroma Biopsy Multiple osteocartilaginous exostoses Chondrosarcoma
a b s t r a c t An osteochrondoma is a benign osseous tumor capped by cartilage. Osteochondromas occurring at the distal tibia and fibula are uncommon and even more so when occurring at the first metatarsal head. Osteochondromas usually occur at the metaphysis of long bones; however, they can occur at other cortical bone metaphyses. This is a case report of a 54-year-old male with incidental radiographic findings of multiple osteochondromas around his ankles as well as a solitary osteochondromatous lesion growing proximally off the left first metatarsal head. The multiple osteochrondomas were evident on multiple views, and subsequent histological analysis of the solitary osteochondromatous lesion via total surgical excision confirmed a diagnosis of multiple hereditary osteochrondromatosis. © 2014 Elsevier Ltd. All rights reserved.
1. Introduction An osteochondroma (osteocartilaginous exostosis), is defined as a benign cartilage-capped osseous tumor [1]. This pathology is a very common osseous neoplasm [1]. Osteochondromas represent 40% of all benign bone tumors and 10% of all osseous tumors [2]. Ten percent of osteochondromas are pedal in origin [1]. Multiple hereditary exostoses (MHE) are diagnosed radiographically by the presence of two or more osteochondromatous lesions [1]. These lesions are inherited in an autosomal dominant pattern and have variable phenotypes [3]. The prevalence in the general population is 1 in 50,000 [1]. Tumors occur most frequently in the first two decades of life, at a male to female ratio of 1.5 to 1.0 [1]. This neoplasm arises only in bones that develop from endochondral ossification and most frequently in the long bones, higher incidence around the knee and the shoulder regions [4]. The etiologies of osteochondromas are congenital or due to trauma of the perichondrium, which results in herniation [4]. Most of the time, they are asymptomatic. However, they can also present with pain due to mechanical irritation of nearby structures, bursitis from chronic friction, or a fracture through the stalk of the lesion [5]. Osteochondromas are detected primarily radigraphically, but can also be detected using other imaging modalities. The typical radiographic
∗ Corresponding author. Tel.: +1 732 616 4095. E-mail address: [email protected] (G. Shtofmakher). http://dx.doi.org/10.1016/j.foot.2014.11.008 0958-2592/© 2014 Elsevier Ltd. All rights reserved.
features of an osteochodroma are that it projects from the metaphysis, it is continuation of the parent bone, and it emanates away from the epiphysis [1]. Histologically, they present as new bone forming in the inner portion of the head and stalk [6]. “The stalk cortex and central region merge with the cortex and medullary cavity of the host bone” [6]. Osteocartilaginous exostoses of the distal and lateral aspects of the tibia are more likely to be symptomatic than those that form on the distal aspect of the fibula [2]. Patients should be informed of the potential malignancy, which occurs in 1–3% of the time, and therefore should be re-evaluated if the lesion becomes larger or painful [3,7,8]. Treatment is only indicated for symptomatic lesions through surgical excision [1]. With the removal of the entire cartilaginous cap, reoccurrence is unlikely [8]; however, partial excision is correlated with a higher rate of reoccurrence and therefore close follow up is necessary [2]. Herrera-Perez et al. presented a case of osteochondromas around the ankle, which was successfully treated with complete surgical excision through an anterior approach [7].
2. Case report A 54-year-old male presented to the clinic with chronic pain at the left 1st metatarsalphalangeal joint (MTPJ) that he has been experiencing for several years. This has affected his ability to participate in athletics and other daily activities. Ambulation was the principle aggravating factor for the pain. The patient had attempted non-operative therapies, such as alterations in shoe gear, arch
G. Shtofmakher et al. / The Foot 25 (2015) 62–65
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Fig. 1. Bilateral pre-operative radiographs were taken showing evidence of multiple osteochondromatous lesion present on medial aspect of the 1st left MTPJ present on left DP (Dorso–Plantar) view, multiple ostochondromatous lesions were evident on the distal tibia bilaterally suggesting possible systemic osteochondromatosis.
supports, and application of topical pain medications, with minimal relief. Past medical history included herniated vertebral discs and a Baker’s cyst in his left knee. Past surgical history included removal of varicose veins. The patient reported that he was not on any medication and had no known allergies. Pedal neurovascular status was intact upon physical examination. Bilateral foot x-rays demonstrated evidence of multiple osteochondromatous lesions with the following characteristics: juxtaposition and cortical growth away from the ankle joints and left 1st MTPJ in the metaphyseal regions. Multiple osteochondromas were visualized in the foot and distal leg (Fig. 1). The patient’s symptom at the left bunion site was attributed principally to the solitary osteochondroma. As part of the surgical correction of bunion deformity, a total excision of solitary osteochondromatous lesion was planned. The patient had an excisional biopsy of the solitary osteochondromatous lesion off the first metatarsal head from the medial eminence of the left foot during an Austin (distal chevron) bunionectomy. Using a sagittal saw, a lytic lesion measuring 1.6 cm × 1.6 cm × 0.5 cm was resected with a through and through osteotomy distal to proximal and passed superiorly from the operative field. The resected bone was sent to pathology to rule out osteochondroma. At the time of the first resected lytic lesion, it was noted that two bone cysts were present at the metatarsal head. Histologically, an osteochondroma was confirmed (Fig. 2A and B). Post-operative radiographs were acquired (Fig. 3), compressive dressings were applied, and the patient was transferred to the recovery room, where his vital signs remained stable and his vascular status was intact (Fig. 4). The patient was followed in the post-operative period, with significant improvement as demonstrated on radiograph and on clinical examination. Radiographically the intermetatarsal (IM) angle was reduced, and no evidence of regrowth or reformation of the osteochrondroma was evident. Clinically the patient had improved passive and active range of motion (ROM), with a reduction in symptomatology (pain levels), which included a reduction in mechanical irritation in shoegear. Lastly, on clinical exam the severity on appearance of the hallux abducto valgus (HAV) deformity was reduced. The patient reported that he was pleased with the outcome of the surgery.
osteochondromas develop chondrosarcoma [9]. Chondrosarcomas generally carry a good prognosis, and surgical treatment without adjuvant chemotherapy or irradiation is standard therapy [9]. However, the actual incidence of malignant transformation has been difficult to estimate due to the high number of undiagnosed osteochondromas. Rare cases of malignant transformation into osteosarcomas have also been reported [10–12]. Confirmation of multiple osteochondromas requires lifelong monitoring of these
3. Discussion Our finding of multiple osteochondromas was incidental on radiographs and confirmed histologically. This finding is principally significant due to the potential for malignancy. Osteochondromas are the most common precursor lesion for secondary chondrosarcomas. An estimated 5–35% of patients with multiple osteochondromas and 1–8% of patients with sporadic
Fig. 2. (A) Histopathologic analysis using hematoxylin and eosin stain at 40× magnification, showing the interface between the osseous and cartilaginous component of an osteochondroma. (B) Histopathologic analysis using hematoxylin and eosin stain at 40× magnification delineating the cartilaginous cap of the osteochondroma.
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G. Shtofmakher et al. / The Foot 25 (2015) 62–65
Fig. 3. Post-operative DP (Dorso–Plantar) radiograph showing surgical excision of osteochondroma on the medial aspect of the 1st MPJ.
osseous neoplasms due to the risk of malignant transformation, which can be fatal. An established genetic component has been described in patients with MHE. The EXT (endoplasmic reticulum-resident type) gene has been associated with MHE [1]. Given an autosomal dominant inheritance pattern of this pathology, it may be necessary to prophylactically screen immediate family members of these
patients. This may support regular screening in people with MHE, which is unknown in this case [11]. In addition to the previously mentioned indications for surgical intervention, recent literature has suggested cartilage cap thickness as a prognostic indicator of potential malignant transformation of osteochrondromas into chondrosarcomas [13]. Typically cartilage cap thickness will decrease as an individual becomes older [14]. The typical cap thickness in an adult is less than 1 cm and thicker in children (2 cm and thicker) [14]. Bernard et al. [13] demonstrated that a cap thickness greater than 2 cm might necessitate surgical intervention due to the potential malignant transformation into a chondrosarcoma. The risk of morbidity with excision of a painful osteochrondroma is reported to be equivalent to that of removal of internal hardware [15]. The overall rates of complications are reported to be between 10.8% and 12.5% [16]. Complications due to excision are pain and swelling which accounts for 98.5% of post-operative complications [17]. Post-operatively 93.4% of patients report resolution in pre-operative symptoms [16], making excision of a symptomatic lesion a viable option for individuals who failed conservative measures. As the patient was middle aged and presented with a benign static tumor that he had since skeletal maturity it is important to mention that Chin et al. [18] have suggested that due to indolent nature of these osseous lesions they are often asymptomatic and thus medical intervention is delayed. As was the case presented here these lesions were incidentally discovered supporting Chin et al. assertion. Literature has emphasized the importance in referring these patients to a specialist for further screening. Pedrini et al. [19] recommend further medical investigation for patients with MHE in order to detect potential malignant transformation. Pedrini et al. recommend that in the case of an adult with multiple exostoses imaging modalities such as ultrasound or radiograph be performed every 18 months, as well as a clinical check-up every 12 to 18 months in adults, and an urgent evaluation in symptomatic exostoses. Pedrini et al. have also established pediatric recommendations. The authors have presented an incidental case of multiple osteochondromas in a 54-year-old male who presented for surgical intervention for bunion correction. This finding was initially visualized radiographically. Subsequently, the pedal osteochondromatous lesion at left 1st MTPJ was resected and confirmed through histopathological analysis. The lesions around both ankles were untreated since they were asymptomatic. This case highlights the
Fig. 4. Clinical post-operative images for the left limb indicating the healing surgical site.
G. Shtofmakher et al. / The Foot 25 (2015) 62–65
importance of proper identification, treatment, and monitoring for patients with multiple osteochondromas. Conflict of interest statement All authors declare that they have no conflicts of interest. References [1] Tarassoli P, Amirfeyz R, Gargan M. Multiple hereditary exostoses. Orthop Trauma 2009;23(6):456–9. [2] Bullough P. Orthopaedic pathology. 3rd ed. London: Times International Publishers T Limited; 1997. [3] D’Ambrosia R, Ferguson Jr AB. The formation of osteochondroma by epiphyseal cartilage transplantation. Clin Orthop Relat Res 1968;61:103–15. [4] Wani IH, Sharma S, Malik FH, Singh M, Shiekh I, Salaria AQ. Distal tibial interosseous osteochondroma with impending fracture of fibula—a case report and review of literature. Cases J 2009;2:115. [5] Giudici MA, Moser Jr RP, Kransdorf MJ. Cartilaginous bone tumors. Radiol Clin North Am 1993;31:237–59. [6] Davids JR, Glancy GL, Eilert RE. Fracture through the stalk of pedunculated osteochondromas. A report of three cases. Clin Orthop Relat Res 1991;271:258–64. [7] Kumar V, Cotran RS, Robbins SL. Robbins basic pathology. 7th ed. Philadelphia, PA: Saunders; 2003. [8] Kharrazi KR, Miller FD, Mankin BS, Gebhardt HJMC. Osteochondromas of the distal aspect of the tibia or fibula. natural history and treatment. J Bone Joint Surg Am 2000;82:1269–78.
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[9] Chou LB, Ho YY, Malawer MM. Tumors of the foot and ankle: experience with 153 cases. Foot Ankle Int 2009;30:836–41. [10] Herrera-Perez M, Aciego De Mendoza M, De Bergua-Domingo JM, Pais-Brito JL. Osteochondromas around the ankle: report of a case and literature review. Int J Surg Case Rep 2013;4:1025–7. [11] Bovee JV, Hogendoorn PC, Wunder JS, Alman BA. Cartilage tumours and bone development: molecular pathology and possible therapeutic targets. Nat Rev Cancer 2010;10:481–8. [12] Mirra JM. Bone tumours: clinical, radiologic and pathologic correlation. Philadelphia, PA: Lea and Febiger; 1989. [13] Bernard SA, Murphey MD, Flemming DJ, Kransdorf MJ. Improved differentiation of benign osteochondromas from secondary chondrosarcomas with standardized measurement of cartilage cap at CT and MR imaging. Radiology 2010;255:857–65. [14] Biermann JS. Common benign lesions of bone in children and adolescents. J Pediatr Orthop 2002;22:268–73. [15] Schmalzried TP, Grogan TJ, Neumeier PA, Dorey FJ. Metal removal in a pediatric population: benign procedure or necessary evil? J Pediatr Orthop 1991;11:72–6. [16] Bottner F, Rodl R, Kordish I, Winklemann W, Gosheger G, Lindner N. Surgical treatment of symptomatic osteochondroma. A three- to eight-year follow-up study. J Bone Joint Surg Br 2003;85:1161–5. [17] Wirganowicz PZ, Watts HG. Surgical risk for elective excision of benign exostoses. J Pediatr Orthop 1997;17:455–9. [18] Chin KR, Kharrazi FD, Miller BS, Mankin HJ, Gebhardt MC. Osteochondromas of the distal aspect of the tibia or fibula. Natural history and treatment. J Bone Joint Surg Am 2000;82:1269–78. [19] Pedrini E, Jennes I, Tremosini M, Milanesi A, Mordenti M, Parra A, et al. Genotype-phenotype correlation study in 529 patients with multiple hereditary exostoses: Identification of “protective” and “risk” factors. J Bone Joint Surg Am 2011;93:2294–302.
Contents lists available at ScienceDirect
The Foot journal homepage: www.elsevier.com/locate/foot
Case report
Multiple osteocartilaginous exostoses of the lower extremity: A case report Garry Shtofmakher ∗ , Michelle A. Kaufman, Prashant H. Bhoola, Ankur A. Patel, Susan M. Rice, Randy E. Cohen New York College of Podiatric Medicine, 53 East 124th Street, New York, NY 10035, United States
a r t i c l e
i n f o
Article history: Received 5 October 2014 Received in revised form 8 November 2014 Accepted 28 November 2014 Keywords: Multiple hereditary osteochrondromatosis Osteochondroma Biopsy Multiple osteocartilaginous exostoses Chondrosarcoma
a b s t r a c t An osteochrondoma is a benign osseous tumor capped by cartilage. Osteochondromas occurring at the distal tibia and fibula are uncommon and even more so when occurring at the first metatarsal head. Osteochondromas usually occur at the metaphysis of long bones; however, they can occur at other cortical bone metaphyses. This is a case report of a 54-year-old male with incidental radiographic findings of multiple osteochondromas around his ankles as well as a solitary osteochondromatous lesion growing proximally off the left first metatarsal head. The multiple osteochrondomas were evident on multiple views, and subsequent histological analysis of the solitary osteochondromatous lesion via total surgical excision confirmed a diagnosis of multiple hereditary osteochrondromatosis. © 2014 Elsevier Ltd. All rights reserved.
1. Introduction An osteochondroma (osteocartilaginous exostosis), is defined as a benign cartilage-capped osseous tumor [1]. This pathology is a very common osseous neoplasm [1]. Osteochondromas represent 40% of all benign bone tumors and 10% of all osseous tumors [2]. Ten percent of osteochondromas are pedal in origin [1]. Multiple hereditary exostoses (MHE) are diagnosed radiographically by the presence of two or more osteochondromatous lesions [1]. These lesions are inherited in an autosomal dominant pattern and have variable phenotypes [3]. The prevalence in the general population is 1 in 50,000 [1]. Tumors occur most frequently in the first two decades of life, at a male to female ratio of 1.5 to 1.0 [1]. This neoplasm arises only in bones that develop from endochondral ossification and most frequently in the long bones, higher incidence around the knee and the shoulder regions [4]. The etiologies of osteochondromas are congenital or due to trauma of the perichondrium, which results in herniation [4]. Most of the time, they are asymptomatic. However, they can also present with pain due to mechanical irritation of nearby structures, bursitis from chronic friction, or a fracture through the stalk of the lesion [5]. Osteochondromas are detected primarily radigraphically, but can also be detected using other imaging modalities. The typical radiographic
∗ Corresponding author. Tel.: +1 732 616 4095. E-mail address: [email protected] (G. Shtofmakher). http://dx.doi.org/10.1016/j.foot.2014.11.008 0958-2592/© 2014 Elsevier Ltd. All rights reserved.
features of an osteochodroma are that it projects from the metaphysis, it is continuation of the parent bone, and it emanates away from the epiphysis [1]. Histologically, they present as new bone forming in the inner portion of the head and stalk [6]. “The stalk cortex and central region merge with the cortex and medullary cavity of the host bone” [6]. Osteocartilaginous exostoses of the distal and lateral aspects of the tibia are more likely to be symptomatic than those that form on the distal aspect of the fibula [2]. Patients should be informed of the potential malignancy, which occurs in 1–3% of the time, and therefore should be re-evaluated if the lesion becomes larger or painful [3,7,8]. Treatment is only indicated for symptomatic lesions through surgical excision [1]. With the removal of the entire cartilaginous cap, reoccurrence is unlikely [8]; however, partial excision is correlated with a higher rate of reoccurrence and therefore close follow up is necessary [2]. Herrera-Perez et al. presented a case of osteochondromas around the ankle, which was successfully treated with complete surgical excision through an anterior approach [7].
2. Case report A 54-year-old male presented to the clinic with chronic pain at the left 1st metatarsalphalangeal joint (MTPJ) that he has been experiencing for several years. This has affected his ability to participate in athletics and other daily activities. Ambulation was the principle aggravating factor for the pain. The patient had attempted non-operative therapies, such as alterations in shoe gear, arch
G. Shtofmakher et al. / The Foot 25 (2015) 62–65
63
Fig. 1. Bilateral pre-operative radiographs were taken showing evidence of multiple osteochondromatous lesion present on medial aspect of the 1st left MTPJ present on left DP (Dorso–Plantar) view, multiple ostochondromatous lesions were evident on the distal tibia bilaterally suggesting possible systemic osteochondromatosis.
supports, and application of topical pain medications, with minimal relief. Past medical history included herniated vertebral discs and a Baker’s cyst in his left knee. Past surgical history included removal of varicose veins. The patient reported that he was not on any medication and had no known allergies. Pedal neurovascular status was intact upon physical examination. Bilateral foot x-rays demonstrated evidence of multiple osteochondromatous lesions with the following characteristics: juxtaposition and cortical growth away from the ankle joints and left 1st MTPJ in the metaphyseal regions. Multiple osteochondromas were visualized in the foot and distal leg (Fig. 1). The patient’s symptom at the left bunion site was attributed principally to the solitary osteochondroma. As part of the surgical correction of bunion deformity, a total excision of solitary osteochondromatous lesion was planned. The patient had an excisional biopsy of the solitary osteochondromatous lesion off the first metatarsal head from the medial eminence of the left foot during an Austin (distal chevron) bunionectomy. Using a sagittal saw, a lytic lesion measuring 1.6 cm × 1.6 cm × 0.5 cm was resected with a through and through osteotomy distal to proximal and passed superiorly from the operative field. The resected bone was sent to pathology to rule out osteochondroma. At the time of the first resected lytic lesion, it was noted that two bone cysts were present at the metatarsal head. Histologically, an osteochondroma was confirmed (Fig. 2A and B). Post-operative radiographs were acquired (Fig. 3), compressive dressings were applied, and the patient was transferred to the recovery room, where his vital signs remained stable and his vascular status was intact (Fig. 4). The patient was followed in the post-operative period, with significant improvement as demonstrated on radiograph and on clinical examination. Radiographically the intermetatarsal (IM) angle was reduced, and no evidence of regrowth or reformation of the osteochrondroma was evident. Clinically the patient had improved passive and active range of motion (ROM), with a reduction in symptomatology (pain levels), which included a reduction in mechanical irritation in shoegear. Lastly, on clinical exam the severity on appearance of the hallux abducto valgus (HAV) deformity was reduced. The patient reported that he was pleased with the outcome of the surgery.
osteochondromas develop chondrosarcoma [9]. Chondrosarcomas generally carry a good prognosis, and surgical treatment without adjuvant chemotherapy or irradiation is standard therapy [9]. However, the actual incidence of malignant transformation has been difficult to estimate due to the high number of undiagnosed osteochondromas. Rare cases of malignant transformation into osteosarcomas have also been reported [10–12]. Confirmation of multiple osteochondromas requires lifelong monitoring of these
3. Discussion Our finding of multiple osteochondromas was incidental on radiographs and confirmed histologically. This finding is principally significant due to the potential for malignancy. Osteochondromas are the most common precursor lesion for secondary chondrosarcomas. An estimated 5–35% of patients with multiple osteochondromas and 1–8% of patients with sporadic
Fig. 2. (A) Histopathologic analysis using hematoxylin and eosin stain at 40× magnification, showing the interface between the osseous and cartilaginous component of an osteochondroma. (B) Histopathologic analysis using hematoxylin and eosin stain at 40× magnification delineating the cartilaginous cap of the osteochondroma.
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G. Shtofmakher et al. / The Foot 25 (2015) 62–65
Fig. 3. Post-operative DP (Dorso–Plantar) radiograph showing surgical excision of osteochondroma on the medial aspect of the 1st MPJ.
osseous neoplasms due to the risk of malignant transformation, which can be fatal. An established genetic component has been described in patients with MHE. The EXT (endoplasmic reticulum-resident type) gene has been associated with MHE [1]. Given an autosomal dominant inheritance pattern of this pathology, it may be necessary to prophylactically screen immediate family members of these
patients. This may support regular screening in people with MHE, which is unknown in this case [11]. In addition to the previously mentioned indications for surgical intervention, recent literature has suggested cartilage cap thickness as a prognostic indicator of potential malignant transformation of osteochrondromas into chondrosarcomas [13]. Typically cartilage cap thickness will decrease as an individual becomes older [14]. The typical cap thickness in an adult is less than 1 cm and thicker in children (2 cm and thicker) [14]. Bernard et al. [13] demonstrated that a cap thickness greater than 2 cm might necessitate surgical intervention due to the potential malignant transformation into a chondrosarcoma. The risk of morbidity with excision of a painful osteochrondroma is reported to be equivalent to that of removal of internal hardware [15]. The overall rates of complications are reported to be between 10.8% and 12.5% [16]. Complications due to excision are pain and swelling which accounts for 98.5% of post-operative complications [17]. Post-operatively 93.4% of patients report resolution in pre-operative symptoms [16], making excision of a symptomatic lesion a viable option for individuals who failed conservative measures. As the patient was middle aged and presented with a benign static tumor that he had since skeletal maturity it is important to mention that Chin et al. [18] have suggested that due to indolent nature of these osseous lesions they are often asymptomatic and thus medical intervention is delayed. As was the case presented here these lesions were incidentally discovered supporting Chin et al. assertion. Literature has emphasized the importance in referring these patients to a specialist for further screening. Pedrini et al. [19] recommend further medical investigation for patients with MHE in order to detect potential malignant transformation. Pedrini et al. recommend that in the case of an adult with multiple exostoses imaging modalities such as ultrasound or radiograph be performed every 18 months, as well as a clinical check-up every 12 to 18 months in adults, and an urgent evaluation in symptomatic exostoses. Pedrini et al. have also established pediatric recommendations. The authors have presented an incidental case of multiple osteochondromas in a 54-year-old male who presented for surgical intervention for bunion correction. This finding was initially visualized radiographically. Subsequently, the pedal osteochondromatous lesion at left 1st MTPJ was resected and confirmed through histopathological analysis. The lesions around both ankles were untreated since they were asymptomatic. This case highlights the
Fig. 4. Clinical post-operative images for the left limb indicating the healing surgical site.
G. Shtofmakher et al. / The Foot 25 (2015) 62–65
importance of proper identification, treatment, and monitoring for patients with multiple osteochondromas. Conflict of interest statement All authors declare that they have no conflicts of interest. References [1] Tarassoli P, Amirfeyz R, Gargan M. Multiple hereditary exostoses. Orthop Trauma 2009;23(6):456–9. [2] Bullough P. Orthopaedic pathology. 3rd ed. London: Times International Publishers T Limited; 1997. [3] D’Ambrosia R, Ferguson Jr AB. The formation of osteochondroma by epiphyseal cartilage transplantation. Clin Orthop Relat Res 1968;61:103–15. [4] Wani IH, Sharma S, Malik FH, Singh M, Shiekh I, Salaria AQ. Distal tibial interosseous osteochondroma with impending fracture of fibula—a case report and review of literature. Cases J 2009;2:115. [5] Giudici MA, Moser Jr RP, Kransdorf MJ. Cartilaginous bone tumors. Radiol Clin North Am 1993;31:237–59. [6] Davids JR, Glancy GL, Eilert RE. Fracture through the stalk of pedunculated osteochondromas. A report of three cases. Clin Orthop Relat Res 1991;271:258–64. [7] Kumar V, Cotran RS, Robbins SL. Robbins basic pathology. 7th ed. Philadelphia, PA: Saunders; 2003. [8] Kharrazi KR, Miller FD, Mankin BS, Gebhardt HJMC. Osteochondromas of the distal aspect of the tibia or fibula. natural history and treatment. J Bone Joint Surg Am 2000;82:1269–78.
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[9] Chou LB, Ho YY, Malawer MM. Tumors of the foot and ankle: experience with 153 cases. Foot Ankle Int 2009;30:836–41. [10] Herrera-Perez M, Aciego De Mendoza M, De Bergua-Domingo JM, Pais-Brito JL. Osteochondromas around the ankle: report of a case and literature review. Int J Surg Case Rep 2013;4:1025–7. [11] Bovee JV, Hogendoorn PC, Wunder JS, Alman BA. Cartilage tumours and bone development: molecular pathology and possible therapeutic targets. Nat Rev Cancer 2010;10:481–8. [12] Mirra JM. Bone tumours: clinical, radiologic and pathologic correlation. Philadelphia, PA: Lea and Febiger; 1989. [13] Bernard SA, Murphey MD, Flemming DJ, Kransdorf MJ. Improved differentiation of benign osteochondromas from secondary chondrosarcomas with standardized measurement of cartilage cap at CT and MR imaging. Radiology 2010;255:857–65. [14] Biermann JS. Common benign lesions of bone in children and adolescents. J Pediatr Orthop 2002;22:268–73. [15] Schmalzried TP, Grogan TJ, Neumeier PA, Dorey FJ. Metal removal in a pediatric population: benign procedure or necessary evil? J Pediatr Orthop 1991;11:72–6. [16] Bottner F, Rodl R, Kordish I, Winklemann W, Gosheger G, Lindner N. Surgical treatment of symptomatic osteochondroma. A three- to eight-year follow-up study. J Bone Joint Surg Br 2003;85:1161–5. [17] Wirganowicz PZ, Watts HG. Surgical risk for elective excision of benign exostoses. J Pediatr Orthop 1997;17:455–9. [18] Chin KR, Kharrazi FD, Miller BS, Mankin HJ, Gebhardt MC. Osteochondromas of the distal aspect of the tibia or fibula. Natural history and treatment. J Bone Joint Surg Am 2000;82:1269–78. [19] Pedrini E, Jennes I, Tremosini M, Milanesi A, Mordenti M, Parra A, et al. Genotype-phenotype correlation study in 529 patients with multiple hereditary exostoses: Identification of “protective” and “risk” factors. J Bone Joint Surg Am 2011;93:2294–302.