Case Report
Intraarticular osteochondroma of the knee Vivek Machhindra Morey, Divesh Jalan, Ravi Mittal, Shivanand Gamangatti1
Abstract Osteochondromas are usually extra articular and grow away from the joint towards the diaphysis. Intraarticular osteochondromas are very rare and often misdiagnosed. We report a case of 16‑year‑old boy who presented with pain and clicking sound in the right knee for last 6 months. On examination, click was felt at the terminal flexion of the knee. The lateral radiograph of the right knee showed a radio opaque shadow at the posterior aspect of the distal end of femur, which was further evaluated with an MRI. Arthroscopy showed a hard lesion arising from the roof of the intercondylar notch of femur. It was excised arthroscopically. Histopathology revealed it to be an osteochondroma. Thus, intraarticular osteochondroma of the knee can be considered as a rare cause of pain in young patients. Key words: Arthroscopy, intraarticular, knee, osteochondroma
Introduction
anterior cruciate ligament (ACL) ganglion cyst, and myxoid degeneration of ACL. Anteroposterior radiographs were normal [Figure 1a]. The lateral radiograph of the right knee showed a radio opaque shadow at the posterior aspect of the distal end of femur [Figure 1b]. Axial and sagittal T2 weighted MR images showed a lobulated heterogeneously hyper intense lesion arising from medial aspect of the lateral femoral condyle [Figure 2]. Medullary cavity of the lateral femoral condyle is continuous with the of the lesion [Figure 2]. Arthroscopy revealed a swelling in the intercondylar notch of the femur occupying most of the space in the flexed knee. On probing it was hard and attached to the roof and lateral wall of the intercondylar notch [Figure 3a]. It was displacing the ACL anteriorly [Figure 3b]. There was evidence of synovitis in the posterior aspect of the joint. Posterior cruciate ligament and menisci were normal in appearance. The lesion was excised with the help of a curved osteotome and removed with grasper [Figure 4]. The base was abraded with a motorized shaver. Excised tumor was sent for histologic examination which revealed cancellous bone covered with cartilage and was diagnosed as an osteochondroma [Figure 5]. Postoperatively, quadriceps and range of motion exercises were started and the patient was mobilized full weight bearing. At 1‑year followup, clicking sounds had disappeared completely, range of motion improved to 0° to 140° and the knee was painless.
O
steochondromas usually grows away from the joint.1 It is usually situated outside the joint and its presence in the joint is very rare. To the best of our knowledge, there have been only three reports of intraarticular osteochondromas of the knee joint.2‑4 We report a rare case of intraarticular osteochondroma arising from the roof of the intercondylar notch of the femur.
Case Report A 16 year old male patient presented with complaints of pain and clicking sounds in the right knee for the last 6‑month. There was no history of trauma, fever or any previous surgery of the knee. There was no effusion or laxity of the joint. A click was felt at the terminal flexion of the knee. The range of motion was from 0° to 130° with painful terminal restriction of flexion. The differential diagnosis considered were meniscal tear, discoid meniscus, Departments of Orthopaedics, and 1Radiology, All India Institute of Medical Sciences, New Delhi, India Address for correspondence: Dr. Divesh Jalan, House no. 1038, Sector‑4, Gurgaon, Haryana - 122 001, India. E‑mail: [email protected]
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Discussion
Website: www.ijoonline.com
Osteochondroma is the most common type of benign bone tumor, true incidence of which is unknown as many are asymptomatic. It is usually found at the metaphysis of long bones commonly around the knee, proximal
DOI: 10.4103/0019-5413.132532
Indian Journal of Orthopaedics | May 2014 | Vol. 48 | Issue 3
332
Morey, et al.: Intraarticular osteochondroma knee
a
b
Figure 3: (a) Arthroscopic image showing a swelling in the intercondylar notch of the femur attached to its roof and lateral wall displacing the ACL anteriorly (b) Arthroscopic image after excision of osteochondroma a
b
Figure 1: Preoperative anteroposterior radiograph (a) and lateral (b) view of the right knee. Arrow in the lateral view shows a radio opaque shadow at the posterior aspect of the distal end of femur
Figure 4: Gross specimen of the lesion showing cancellous bony mass covered with cartilaginous cap
Figure 5: Photomicrographs showing mature cartilage cap over bony stalk (H and E, ×100 and ×200)
in the patellofemoral joint presenting with pain and clicking sounds and underwent an arthroscopic resection. The case they reported was a known case of multiple osteochondromatosis and was also previously operated for osteochondroma around the knee. Schmoyer and Ciullo3 reported a case of arthroscopic resection of an osteochondroma of the knee where the authors suspected it to be an extra articular lesion after they had excised it. Dienst et al.4 reported a case of osteochondroma of the posterior knee joint cavity. However, the origin and pathogenesis of osteochondroma remained uncertain in their case too. They assumed that osteochondroma originated at the posterior end plate of the tibia and femur and grew towards the joint cavity. The pedicle could have been broken so that osteochondroma became truly loose within the knee joint. Siebenrock and Ganz5 reported four cases of osteochondroma of the femoral neck, which was intraarticular in the hip joint. They performed open
Figure 2: Sagittal and axial T2 weighted MR image showing a lobulated heterogeneously hyperintense lesion arising from medial aspect of the lateral femoral condyle. Medullary cavity of the lateral femoral condyle is continuous with the medulla of the lesion
femur, and proximal humerus although they may develop in any bone that is formed by endochondral ossification. With growth, these lesions grow from the metaphysis toward diaphysis away from the joint. Till date, to our knowledge, there are only three case reports of intraarticular osteochondromas of the knee2‑4 [Table 1]. Masaaki Takahashi et al.2 reported a case in which the patient had intraarticular osteochondroma
333
Indian Journal of Orthopaedics | May 2014 | Vol. 48 | Issue 3
Morey, et al.: Intraarticular osteochondroma knee Table 1: Other studies on intraarticular osteochondroma Study Masaaki Takahashi et al.2
Site Knee
Management Arthroscopic resection
Schmoyer S, Ciullo JV3
Knee
Arthroscopic resection
Michael Dienst et al.4
Knee
Siebenrock and Ganz5 Yamashita et al.6
Hip
Excision using posterior approach to the knee joint Open resection
Ankle
Open resection
In the literature, intraarticular osteochondromas were seen either in a patient of multiple osteochondromatosis or the origin and pathogenesis remained uncertain. In our case, the osteochondroma was seen arising from the roof of the intercondylar notch. As the growth plate of distal femur is very close to the roof of the intercondylar notch, it can very well explain this location. The clinical presentation of our case was quite similar to that of ACL myxoid degeneration and ACL ganglion cyst. However, the radiographs and MRI could help us to differentiate it.
Remark Known case of multiple osteochondromatosis operated previously in the other knee Authors suspected it to be an extra articular lesion after they had excised it Origin and pathogenesis of osteochondroma remained uncertain Origin from the femoral neck Arthroscopy was done to assess the lesion
To the best of our knowledge, this is the first case of solitary intraarticular osteochondroma of the knee joint arising from intercondylar notch and managed successfully with arthroscopic excision. We conclude that intraarticular osteochondroma of the knee can be considered as a rare cause of pain in young patients.
resection in all the cases. Yamashita et al.6 reported an intraarticular osteochondroma of the ankle joint. The causes of clicking knee are meniscal tear, discoid meniscus, patellar maltracking, ACL ganglion cyst, plica, and arthritis. The patient was investigated with MRI of the knee joint. Although, CT scan could have been a better modality to assess a bony outgrowth but in our case, nature of the lesion was not very clear after the clinical and radiographic examination; hence, we went for MRI instead of CT scan. As the next step of management was diagnostic/therapeutic arthroscopy and there was financial constraint, CT scan was not done after the MRI.
References 1. Bleshman MH, Levy RM. An unusual location of an osteochondroma. Radiology 1978;127:456. 2. Takahashi M, Nishihara A, Ohishi T, Shiga K, Yamamoto K, Nagano A. Arthroscopic Resection of an Intraarticular Osteochondroma of the Knee in the Patient with Multiple Osteochondromatosis. Arthroscopy 2004;20:28‑31. 3. Schmoyer S, Ciullo JV. Arthroscopic resection of an osteochondroma of the knee. Arthoscopy 2001;17:765‑7. 4. Dienst M, Schneider G, Pahl S, Ensslin S, Kohn D. Intraarticular osteochondroma of the posterior cavity of the knee. Arch Orthop Trauma Surg 2002;122:462‑5. 5. Siebenrock KA, Ganz R. Osteochondroma of the femoral neck. Clin Orthop Relat Res 2002;394:211‑8. 6. Yamashita T, Usui M, Sakamoto N, Fujisawa Y, Ichikawa I. Intraarticular osteochondroma of the ankle joint. J Foot Ankle Surg 1998;37:66‑8.
There were two treatment options, open resection or arthroscopic resection of the lesion, excluding the option of conservative management as the patient was symptomatic with pain and had clicking sounds and the investigations were suggestive of a bony lesion in the intercondylar notch. We decided to go for arthroscopy of the knee and to attempt for arthroscopic resection, keeping in mind the possibility of opening the joint in case of failure to do the same. We were successful in excising it arthroscopically, because of the small size. We were able to excise the tumor en‑bloc which helped us further to reach to a diagnosis of osteochondroma on histopathological examination.
Indian Journal of Orthopaedics | May 2014 | Vol. 48 | Issue 3
How to cite this article: Morey VM, Jalan D, Mittal R, Gamangatti S. Intraarticular osteochondroma of the knee. Indian J Orthop 2014;48:332-4. Source of Support: No support was received in the form of grants, drugs, or equipments, Conflict of Interest: All Named authors hereby declare that they have no conflicts of interest to disclose.
334
Copyright of Indian Journal of Orthopaedics is the property of Medknow Publications & Media Pvt. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Intraarticular osteochondroma of the knee Vivek Machhindra Morey, Divesh Jalan, Ravi Mittal, Shivanand Gamangatti1
Abstract Osteochondromas are usually extra articular and grow away from the joint towards the diaphysis. Intraarticular osteochondromas are very rare and often misdiagnosed. We report a case of 16‑year‑old boy who presented with pain and clicking sound in the right knee for last 6 months. On examination, click was felt at the terminal flexion of the knee. The lateral radiograph of the right knee showed a radio opaque shadow at the posterior aspect of the distal end of femur, which was further evaluated with an MRI. Arthroscopy showed a hard lesion arising from the roof of the intercondylar notch of femur. It was excised arthroscopically. Histopathology revealed it to be an osteochondroma. Thus, intraarticular osteochondroma of the knee can be considered as a rare cause of pain in young patients. Key words: Arthroscopy, intraarticular, knee, osteochondroma
Introduction
anterior cruciate ligament (ACL) ganglion cyst, and myxoid degeneration of ACL. Anteroposterior radiographs were normal [Figure 1a]. The lateral radiograph of the right knee showed a radio opaque shadow at the posterior aspect of the distal end of femur [Figure 1b]. Axial and sagittal T2 weighted MR images showed a lobulated heterogeneously hyper intense lesion arising from medial aspect of the lateral femoral condyle [Figure 2]. Medullary cavity of the lateral femoral condyle is continuous with the of the lesion [Figure 2]. Arthroscopy revealed a swelling in the intercondylar notch of the femur occupying most of the space in the flexed knee. On probing it was hard and attached to the roof and lateral wall of the intercondylar notch [Figure 3a]. It was displacing the ACL anteriorly [Figure 3b]. There was evidence of synovitis in the posterior aspect of the joint. Posterior cruciate ligament and menisci were normal in appearance. The lesion was excised with the help of a curved osteotome and removed with grasper [Figure 4]. The base was abraded with a motorized shaver. Excised tumor was sent for histologic examination which revealed cancellous bone covered with cartilage and was diagnosed as an osteochondroma [Figure 5]. Postoperatively, quadriceps and range of motion exercises were started and the patient was mobilized full weight bearing. At 1‑year followup, clicking sounds had disappeared completely, range of motion improved to 0° to 140° and the knee was painless.
O
steochondromas usually grows away from the joint.1 It is usually situated outside the joint and its presence in the joint is very rare. To the best of our knowledge, there have been only three reports of intraarticular osteochondromas of the knee joint.2‑4 We report a rare case of intraarticular osteochondroma arising from the roof of the intercondylar notch of the femur.
Case Report A 16 year old male patient presented with complaints of pain and clicking sounds in the right knee for the last 6‑month. There was no history of trauma, fever or any previous surgery of the knee. There was no effusion or laxity of the joint. A click was felt at the terminal flexion of the knee. The range of motion was from 0° to 130° with painful terminal restriction of flexion. The differential diagnosis considered were meniscal tear, discoid meniscus, Departments of Orthopaedics, and 1Radiology, All India Institute of Medical Sciences, New Delhi, India Address for correspondence: Dr. Divesh Jalan, House no. 1038, Sector‑4, Gurgaon, Haryana - 122 001, India. E‑mail: [email protected]
Access this article online Quick Response Code:
Discussion
Website: www.ijoonline.com
Osteochondroma is the most common type of benign bone tumor, true incidence of which is unknown as many are asymptomatic. It is usually found at the metaphysis of long bones commonly around the knee, proximal
DOI: 10.4103/0019-5413.132532
Indian Journal of Orthopaedics | May 2014 | Vol. 48 | Issue 3
332
Morey, et al.: Intraarticular osteochondroma knee
a
b
Figure 3: (a) Arthroscopic image showing a swelling in the intercondylar notch of the femur attached to its roof and lateral wall displacing the ACL anteriorly (b) Arthroscopic image after excision of osteochondroma a
b
Figure 1: Preoperative anteroposterior radiograph (a) and lateral (b) view of the right knee. Arrow in the lateral view shows a radio opaque shadow at the posterior aspect of the distal end of femur
Figure 4: Gross specimen of the lesion showing cancellous bony mass covered with cartilaginous cap
Figure 5: Photomicrographs showing mature cartilage cap over bony stalk (H and E, ×100 and ×200)
in the patellofemoral joint presenting with pain and clicking sounds and underwent an arthroscopic resection. The case they reported was a known case of multiple osteochondromatosis and was also previously operated for osteochondroma around the knee. Schmoyer and Ciullo3 reported a case of arthroscopic resection of an osteochondroma of the knee where the authors suspected it to be an extra articular lesion after they had excised it. Dienst et al.4 reported a case of osteochondroma of the posterior knee joint cavity. However, the origin and pathogenesis of osteochondroma remained uncertain in their case too. They assumed that osteochondroma originated at the posterior end plate of the tibia and femur and grew towards the joint cavity. The pedicle could have been broken so that osteochondroma became truly loose within the knee joint. Siebenrock and Ganz5 reported four cases of osteochondroma of the femoral neck, which was intraarticular in the hip joint. They performed open
Figure 2: Sagittal and axial T2 weighted MR image showing a lobulated heterogeneously hyperintense lesion arising from medial aspect of the lateral femoral condyle. Medullary cavity of the lateral femoral condyle is continuous with the medulla of the lesion
femur, and proximal humerus although they may develop in any bone that is formed by endochondral ossification. With growth, these lesions grow from the metaphysis toward diaphysis away from the joint. Till date, to our knowledge, there are only three case reports of intraarticular osteochondromas of the knee2‑4 [Table 1]. Masaaki Takahashi et al.2 reported a case in which the patient had intraarticular osteochondroma
333
Indian Journal of Orthopaedics | May 2014 | Vol. 48 | Issue 3
Morey, et al.: Intraarticular osteochondroma knee Table 1: Other studies on intraarticular osteochondroma Study Masaaki Takahashi et al.2
Site Knee
Management Arthroscopic resection
Schmoyer S, Ciullo JV3
Knee
Arthroscopic resection
Michael Dienst et al.4
Knee
Siebenrock and Ganz5 Yamashita et al.6
Hip
Excision using posterior approach to the knee joint Open resection
Ankle
Open resection
In the literature, intraarticular osteochondromas were seen either in a patient of multiple osteochondromatosis or the origin and pathogenesis remained uncertain. In our case, the osteochondroma was seen arising from the roof of the intercondylar notch. As the growth plate of distal femur is very close to the roof of the intercondylar notch, it can very well explain this location. The clinical presentation of our case was quite similar to that of ACL myxoid degeneration and ACL ganglion cyst. However, the radiographs and MRI could help us to differentiate it.
Remark Known case of multiple osteochondromatosis operated previously in the other knee Authors suspected it to be an extra articular lesion after they had excised it Origin and pathogenesis of osteochondroma remained uncertain Origin from the femoral neck Arthroscopy was done to assess the lesion
To the best of our knowledge, this is the first case of solitary intraarticular osteochondroma of the knee joint arising from intercondylar notch and managed successfully with arthroscopic excision. We conclude that intraarticular osteochondroma of the knee can be considered as a rare cause of pain in young patients.
resection in all the cases. Yamashita et al.6 reported an intraarticular osteochondroma of the ankle joint. The causes of clicking knee are meniscal tear, discoid meniscus, patellar maltracking, ACL ganglion cyst, plica, and arthritis. The patient was investigated with MRI of the knee joint. Although, CT scan could have been a better modality to assess a bony outgrowth but in our case, nature of the lesion was not very clear after the clinical and radiographic examination; hence, we went for MRI instead of CT scan. As the next step of management was diagnostic/therapeutic arthroscopy and there was financial constraint, CT scan was not done after the MRI.
References 1. Bleshman MH, Levy RM. An unusual location of an osteochondroma. Radiology 1978;127:456. 2. Takahashi M, Nishihara A, Ohishi T, Shiga K, Yamamoto K, Nagano A. Arthroscopic Resection of an Intraarticular Osteochondroma of the Knee in the Patient with Multiple Osteochondromatosis. Arthroscopy 2004;20:28‑31. 3. Schmoyer S, Ciullo JV. Arthroscopic resection of an osteochondroma of the knee. Arthoscopy 2001;17:765‑7. 4. Dienst M, Schneider G, Pahl S, Ensslin S, Kohn D. Intraarticular osteochondroma of the posterior cavity of the knee. Arch Orthop Trauma Surg 2002;122:462‑5. 5. Siebenrock KA, Ganz R. Osteochondroma of the femoral neck. Clin Orthop Relat Res 2002;394:211‑8. 6. Yamashita T, Usui M, Sakamoto N, Fujisawa Y, Ichikawa I. Intraarticular osteochondroma of the ankle joint. J Foot Ankle Surg 1998;37:66‑8.
There were two treatment options, open resection or arthroscopic resection of the lesion, excluding the option of conservative management as the patient was symptomatic with pain and had clicking sounds and the investigations were suggestive of a bony lesion in the intercondylar notch. We decided to go for arthroscopy of the knee and to attempt for arthroscopic resection, keeping in mind the possibility of opening the joint in case of failure to do the same. We were successful in excising it arthroscopically, because of the small size. We were able to excise the tumor en‑bloc which helped us further to reach to a diagnosis of osteochondroma on histopathological examination.
Indian Journal of Orthopaedics | May 2014 | Vol. 48 | Issue 3
How to cite this article: Morey VM, Jalan D, Mittal R, Gamangatti S. Intraarticular osteochondroma of the knee. Indian J Orthop 2014;48:332-4. Source of Support: No support was received in the form of grants, drugs, or equipments, Conflict of Interest: All Named authors hereby declare that they have no conflicts of interest to disclose.
334
Copyright of Indian Journal of Orthopaedics is the property of Medknow Publications & Media Pvt. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
