Chondromalacia Patellae

Chondromalacia of the patella is a condition characterized by a series of degenerative changes that involve the cartilage and subchondral bone in the retropatellar facet. Clinically, two different types have been described on the basis

Chondromalacia Patellae Crab Meat

Fig. 9.17A, B Chondromalacia patellae associated with osteoarthritis. A Medial pinhole scan of the right knee in a 70-year-old woman shows spotty intense tracer uptake typically localized in the upper posterior aspect of the patella surrounded by less intense uptake (arrowhead). The patellofemoral and lateral femorotibial compartments accumulate tracer diffusely, designating associated osteoarthritis (arrows). B Mediolateral radiograph shows a small cystic change in the upper posterior aspect of the patella (arrow) and diffuse periarticular sclerosis in the patellofemoral and femorotibial compartments. CT scan confirmed roughened cartilage with subchondral cysts (not shown here)

Fig. 9.17A, B Chondromalacia patellae associated with osteoarthritis. A Medial pinhole scan of the right knee in a 70-year-old woman shows spotty intense tracer uptake typically localized in the upper posterior aspect of the patella surrounded by less intense uptake (arrowhead). The patellofemoral and lateral femorotibial compartments accumulate tracer diffusely, designating associated osteoarthritis (arrows). B Mediolateral radiograph shows a small cystic change in the upper posterior aspect of the patella (arrow) and diffuse periarticular sclerosis in the patellofemoral and femorotibial compartments. CT scan confirmed roughened cartilage with subchondral cysts (not shown here)

Chondromalacia Patella
Fig. 9.18A, B Bone scintigraphic sign of chondromalacia patellae. A CT of the left patella in a 63-year-old male shows a small sharply defined subchondral cyst with sclerosis in the medial retropatellar facet (arrow). B Lateral pinhole scan reveals two spotty "hot" areas (arrows)

of the age and symptom. The first type, which is traditionally referred to as chondromalacia patellae, manifests as pain and crepitus over the patella in young adults and adolescents. The second type is a disease of older age. It is not necessarily associated with osteoarthritis in the femoropatellar joint.

Pathologically, in the initial stage the cartilage on the retropatellar facet undergoes softening and swelling, in the second and third stages fissuring and fibrillation with a "crab meat" appearance, and in the final stage thinning and ulceration. As a result, the subchondral bone becomes exposed (Wiles et al. 1956). According to Goodfellow et al. (1976), the changes in the

Ankle Chondromalacia
Fig. 9.19A, B Preradiographic manifestation of talar osteoarthritis. A Lateral pinhole scan of painful right ankle in a 31-year-old female shows spotty uptake in the anterior subtalar joint (arrow). B Lateral radiograph shows no abnormality (?)

on of cartilage (Fig. 9.16B) and cystic change (Fig. 9.18A) in the subchondral bone. Concomitant degenerative change may occur, although this is not essential.

Scintigraphy reveals abnormal tracer uptake in 54% of patients with patellar pain (Dye and Boll 1986). Pinhole scintigraphy can reveal a specific sign (Bahk et al. 1994). This consists of small "hot" spotty uptake localized to the central retropatellar facet, denoting cartilage aberration and cystic change (Figs. 9.16C and 9.18B). Less intense reactive uptake may be present in the remaining patella. In the classic cases no associated lesions are present in other parts of the affected knee. The chondromalacia patellae associated with osteoarthritis can be readily recognized as such by pinhole scanning because, in addition to the characteristic retro-patellar uptake, accompanying changes appear in the other articular compartments of the knee (Fig. 9.17A). Occasionally, the lesion may be doubled (Fig. 9.18). For differential diagnosis it is to be pointed out that osteoarthritis of the patella characteristically involves the lower or upper edge of the retropatellar facet with small osteophytosis (Figs. 9.14 and 9.15).

Arthritis Joint Pain

Arthritis Joint Pain

Arthritis is a general term which is commonly associated with a number of painful conditions affecting the joints and bones. The term arthritis literally translates to joint inflammation.

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