A 48-Year-Old Man With An Excruciating Pain In His Left Knee

Abstract

A man is complaining for pain in both medial and lateral femoral of his left lower limb especially during knee flexion. His is not suffering from any disease and his laboratory tests are unremarkable. During the physical examination, he has a positive Ober’s test. In the MRI a minute fracture in the joint surface was revealed. The final diagnosis of his condition is that of spontaneous osteonecrosis of the knee (SPONK) complicated by iliotibial band syndrome. After 5 monhs of conservative treatment he is able to walk for short distances without feeling any pain. It is important to differentiate between the 2 separate entities, SPONK and secondary osteonecrosis, in order to treat each disease appropriately. For SPONK conservative treatment has good results, while for secondary osteonecrosis a surgical solution should be preferred. BACKGROUND A 48-year-old man presents to the outpatient department of the orthopaedic clinic complaining for an excruciating pain in the area of both medial and lateral femoral condyles of his left lower limb. The symptoms begun from the medial condyle nearly a month ago but during the last 3-4 days the painful sensation is more intense in the region of the lateral condyle. He reports that the pain is not constant during normal walking and that it is aggravated when he is climbing up or down the stairs. The patient is doing a sedentary work and he spends a lot of time in front of a computer. He doesn’t remember to have injured his knee recently. He is not suffering from any other disease or allergy and he is not under any medication. He is a smoker of 20 cigarettes a day. On physical examination, the general appearance of the patient was normal with a heart rate of 80 bpm, blood pressure of 130/82 mm Hg, a respiratory rate of 12 breaths/min, and a temperature of 98.6°F (37.0°C). His musculoskeletal system appears normal and only a slight effusion in the left knee was revealed without any noticeable muscular atrophy or skin discoloration. The girth measurement of the left knee was slightly bigger than that of the right knee (42 cm versus 40 cm) at the level of the patella. Measurements taken 5 cm and 20 cm proximal to the base of the patella and 15 cm distal to the apex of the patella were practically the same for both knees and in the normal range. During palpation pain was elicited over the area of the medial femoral condyle especially during knee flexion. This pain was radiating over to the lateral femoral condyle. There was a painful restriction of knee’s flexion while the strength testing was found normal for both knee flexion and extension. The Ober’s test was performed and was found positive. Routine laboratory tests were performed in order to rule out any autoimmune or infectious disease. The X-ray of the knee was found also normal. In the MRI examination that was performed subsequently, edema was revealed as well as a minute fracture in the joint surface which exactly corresponds to the painful area (Figure 1). A 48-Year-Old Man With An Excruciating Pain In His Left Knee 2 of 4 Figure 1 Figure 1 The patient left the hospital with the prescription of non steroidal anti-inflammatory drugs (NSAIDs) and the advice of walking with crutches keeping the affected limb on partial weightbearing (20-50% of body weight) for 6 weeks and to follow a specific physical therapy program. He also got kinesiotaping as dressing that alleviated him from the pain. He returned to his work and at the normal Activities of Daily Living (ADL) when he felt better at approximately 2 weeks. After 6 weeks the symptoms persisted and even worsen, so a second MRI scan was ordered. (Figure 2)