Bipartite Patella Jessup MD
Glen Burnie, MD
Bay Area Orthopaedics & Sports Medicine
Medical School: Univ Of Md Sch Of Med, Baltimore Md 21201
Graduation Year: 1968
Hospital: Howard County General Hospital, Columbia, Md
Group Practice: Patuxent Medical Group
Takoma Park, MD
National Orthopedics PC
Medical School: Kirksville Coll Of Osteo Med, Kirksville Mo 63501
Graduation Year: 1982
A Patient's Guide to Bipartite Patella
Bipartite patella is a congenital condition (present at birth) that occurs when the patella (kneecap) is made of two bones instead of a single bone. Normally, the two bones would fuse together as the you grow. But in bipartite patella, they remain as two separate bones. About one per cent of the population has this condition. Boys are affected much more often than girls. When this condition is discovered in adulthood it is oftentimes an “incidental finding”.
This guide will help you understandwhat parts of the knee are involved how this condition develops how doctors diagnose this condition what treatment options are available Anatomy
What is the patella and what does it do?
The knee is the meeting place of two important bones in the leg, the femur (the thighbone) and the tibia (the shinbone). The patella (kneecap) is the moveable bone that sits in front of the knee. This unique bone is wrapped inside a tendon that connects the large muscles on the front of the thigh, the quadriceps muscles , to the lower leg bone.
Related Document: A Patient's Guide to Knee AnatomyCauses
What causes this condition?
The patella starts out as a piece of fibrous cartilage. It turns into bone or ossifies as part of the growth process. Each bone has an ossification center. This is the first area of the structure to start changing into bone.
Most bones (including the patella) only have one primary ossification center. But in some cases, a second ossification center is present. Normally, these two centers of bone will fuse together during late childhood or early adolescence. If they don’t ossify together, then the two pieces of bone remain connected by fibrous or cartilage tissue. This connective tissue is called a synchondrosis .
The most common location of the second bone is the supero-lateral (upper outer) corner of the patella. But the problem can occur at the bottom of the patella or along the side of the kneecap.
Injury or direct trauma to the synchondrosis can cause a separation of this weak union leading to inflammation. Repetitive microtrauma can have the same effect. The cartilage has a limited ability to repair itself. The increased mobility between the main bone and the second ossification center further weakens the synchondrosis resulting in painful symptoms.Symptoms
What does bipartite patella feel like?
Most of the time, there are no symptoms. Sometimes there is a bony bump or place where the bone sticks out more on one side than the other. If inflammation of the fibrous tissue between the two bones occurs, then painful symptoms develop directly over the kneecap. The pain is usually described as dull aching. There may be some swelling.
Movement of the knee can be painful, especially when bending the joint. Atrophy of the quadriceps and malalignment of the patella can lead to patellar tracking problems. Squatting, stair climbing, weight trai...