Orthopedics - Oleksa A.P. 2006

Osteochondropathies
Osteochondropathies of the Bones of the Lower Extremity
Osteochondropathy of the Patella (Sinding-Larsen-Johansson Disease)

Described by Sinding-Larsen and Johanson, Osteochondropathy of the Patella is extremely rare and therefore frequently goes undiagnosed.

The condition has a gradually progressive course, beginning with spontaneous pain in the patella that intensifies during maximum flexion of the lower leg. On examination, the knee appears normal and passive range of motion is fully preserved, though the patient experiences pain upon flexion and consequently guards the leg to some extent.

Palpation may occasionally reveal soft tissue doughiness (pasty consistency) around the patella, along with mild joint synovitis. The primary diagnostic modality for patellar osteochondropathy is radiographic examination. A lateral knee radiograph with patellar-specific views (3/4 and true lateral) is particularly informative. A standard Overview radiograph may only reveal abnormalities once subchondral necrosis fragmentation occurs and patchy areas become visible within the patella.

In the Cytology/cytology/16.html">Early stages of the condition, computed tomography—by assessing the comparative bone density of the patellae—as well as Magnetic Resonance imaging are the most informative diagnostic tools. Furthermore, these imaging studies help differentiate osteochondropathy from Tuberculosis of the patella or congenital anomalies such as multipartite patella (patella bi-tripartita), where each fragment features a separate ossification center.

In most cases during the early stage of osteochondropathy, when no radiographic changes are detectable, a Diagnosis of post-traumatic patellitis is made, even though the medical history lacks clear evidence of trauma. Only the prolonged course of the disease and a comprehensive re-examination of the patient allow for an accurate diagnosis to be established.

Treatment. First and foremost, patients are advised to minimize physical stress on the limb, avoid athletic activities, running, prolonged walking, and squatting, and use a supportive elastic knee brace or sleeve.

A combination of physical therapy and balneotherapy administered in alternating courses is prescribed, alongside pharmacotherapy (such as profenid, voltaren derivatives, etc.). The disease typically lasts 5–6 months, after which gradual recovery occurs without any adverse sequelae.