Arthroscopy: The Journal of Arthroscopic and Related Surgery 8(3)370-372 Published by Raven Press, Ltd. 0 1992 Arthroscopy Association of North America
Case Report
Arthroscopic B. Cohen, F.R.C.S.
Resection of Chondroblastoma Ed., T. H. Khan, M.B.B.S.,
of the Knee
and D. J. Dandy, M.D., F.R.C.S.
Summary: We present a case of chondroblastoma of the upper tibia treated by complete arthroscopic excision. The diagnostic difficulties raised by the case are discussed. This method of treatment has not, to our knowledge, been reported in the literature. Key Words: Chondroblastoma-Knee.
CASE REPORT
knee became swollen, warm, and indurated. Radiographs showed subchondral rarefaction, and lucency of the tibia1 spine. He was thought to have a subclinical joint infection and underwent lavage of the knee, but no fluid was found in the joint, and no organism was grown on culture. He was treated with intravenous fucidic acid and flucloxacillin, and penicillin was instilled into the joint. His condition improved, and during the next 12 months he remained systemically well, although he developed a 30” fixed flexion deformity of the knee and was only able to flex to 90”. Further radiographs of the knee were made. These showed an area of lucency in the region of the anterior tibia1 spine extending into the epiphysis with an irregular, ill-defined sclerotic border (Fig. 1). A 99mT~isotope bone scan was performed, which demonstrated markedly increase tracer uptake associated with the right upper tibia (Fig. 2). A 67Galabelled white cell scan was normal. Magnetic resonance (MR) imaging of the knee showed decreased signal intensity in the intercondylar region with evidence of synovial hypertrophy, most marked in the anterior intercondylar region (Fig. 3). At arthroscopy there was a large swelling covered with inflamed synovium arising from the tibia in the intercondylar notch on the medial side of the anterior cruciate ligament. This mass consisted of an overlying layer of soft bone, and a deeper darkbrown lesion measuring -0.5 cm in diameter was removed arthroscopically, leaving a cavity of healthy bone. On histological examination the le-
A 13-year-old boy presented in October 1988 with a 3-month history of pain and instability of the right knee. His symptoms had begun after a 2-week tennis course, although no definite single injury was noted. On examination there was a block to passive hyperextension, and flexion was limited by 15” compared with the left knee. He was tender along the lateral tibiofemoral joint line and McMurray’s test caused pain. Radiographs of the knee were normal. He underwent arthroscopy, and a detached peripheral tear of the posterior horn of the lateral meniscus was resected. After surgery his symptoms improved, but after 4 months he gradually developed increasing pain and tenderness along the lateral joint line and a 10” degree block to extension. A second arthroscopy carried out in March 1989 showed synovitis around the anterior horn of the lateral meniscus and the adjacent fat pad. An anterolateral arthrotomy of the joint was performed and the remaining lateral meniscus was excised. The knee remained painful and kept him awake at night, and 1 month later he became unwell with anorexia, general malaise, and a fever of 100°F. The
From the Department of Orthopaedics and Histopathology, Addenbrooke’s Hospital, Cambridge, England. Address correspondence and reprint requests to Dr. D. J. Dandy at The Old Vicarage, Great Wilbraham, Cambridge CBl 5JF, England.
370
ARTHROSCOPIC
RESECTION
OF KNEE CHONDROBLASTOMA
371
The diagnosis of his underlying condition was made more difficult because he developed a subclinical joint infection after his second arthroscopy. On MR imaging, the lesion gave a typical, although not pathognomonic, low signal intensity on both long and short TRlTE sequences (11) and aided surgery by defining the extent of the lesion. The recommended treatment of choice remains thorough curettage through either an intraarticular approach or a window in the cortex. Tumour recurrence has been reported to occur in IO-20% of cases
FIG. 1. Radiograph shows chondroblastoma
in the upper tibia.
sion showed the classic appearance of a chondroblastoma with an associated nonspecific synovitis. At review 1 year after operation, the knee was pain free and he had full flexion and extension. There has been no radiological evidence of recurrence. DISCUSSION In 1942, Jaffe and Lichtenstein (1) introduced the term “benign chondroblastoma” for the variant of giant cell tumour with cartilage reported by Kolodny (2), Ewing (3), and Codman (4). The tumour occurs most commonly in the lower end of the femur (5,6) and proximal end of the humerus, and accounts for - 1% of all benign bone tumours (7). It affects the upper epiphysis of the tibia in 17% of cases (8), and characteristically presents with pain, often related to the knee. Bloem and Mulder (9) have observed that an erroneous clinical diagnosis of a meniscal tear may be made in the presence of a joint effusion, particularly with a history of trauma, and other authors have drawn attention to extraarticular lesions of bone that may simulate intraarticular pathology of the knee (10). Our patient had a tear of the lateral meniscus and a normal radiograph on initial presentation and only later developed characteristic radiological changes in the upper tibia.
F5
FIG . 2 . ““Tc isotope bone scan shows increased uptake in the upper tibia.
Arthroscopy,
Vol. 8. No. 3, 1992
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B. COHEN ET AL. scopic resection of a chondroblastoma previously reported.
has not been
REFERENCES
FIG. 3. Magnetic resonance imaging scan shows decreased signal intensity in the intercondylar region of the knee.
(6,7) and is considered to be a reflection of inadequate initial removal. Anterolateral, anteromedial, and posteromedial arthroscopic portals provided adequate access to the tumour in this case. To our knowledge, arthro-
Arthroscopy, Vol. 8, NO. 3, 1992
1. Jaffe HL, Lichtenstein L. Benign chondroblastoma of bone. A reinterpretation of the so-called calcifying or chondromatous giant-cell tumour. Am J Pathol 1942;18:969-91. 2. Kolodny A. Bone sarcoma: the primary malignant tumour of bone and the giant-cell tumour. Surg Gynecol Obster 1927;44(suppl l):l-214. 3. Ewing J. In: Neoplastic diseases. A textbook of turnours. Philadelphia: WB Saunders, 1928:293. 4. Codman EA. Epiphyseal chondromatous giant cell tumours of the upper end of the humerus. Surg Gynecol Obstet 1931; 52~543-8. 5. Schalowicz F, Galardo H. Epiphyseal chondroblastoma of bone. A clinico-pathological study of sixty-nine cases. J Bone Joint Surg [Br] 1970;52:205-26. 6. Dahlin DC, Ivins JC. Benign chondroblastoma. A study of 125 cases. Cancer 1972;30:401-13. 7. Huvos AG, Marcove RC. Chondroblastoma of bone. A critical review. Clin Orthop 1973;95:30&12. 8. Springfield DS, Capana R, Gherlinzoni F, Picci P, Campanacci M. Chondroblastoma: a review of seventy cases. J Bone Joint Surg [Am] 1985;67:748-55. 9. Bloem JH. Mulder JD. Chondroblastoma: a clinical and radiological study of 104 cases. Skeleta/ Radio/ 1985;14:1-9. 10. Joyce MJ, Mankin HJ. Caveat arthroscopes: extra-articular lesions on bone stimulating intra-articular pathology of the knee. J Bone Joint Surg [Am] 1983;65:289-92. I’. Fobben ES, Dalinka MK, Scheibler ML, et al. Magnetic resonance imaging appearance at 1.5 Tesla of cartilaginous tumours involving the epiphysis. Skeletal Radio1 1987;16: 647-5 1.