The knee joint relies on two C-shaped pieces of cartilage called the menisci, which act as shock absorbers between the thigh bone and the shin bone. Injuries to these structures are common, especially in sports that involve twisting or pivoting movements. Among the various types of meniscal damage, the bucket handle tear is a specific and severe injury that often requires immediate medical attention.
Defining the Bucket Handle Tear
The menisci are crescent-shaped pads that sit on the top of the tibia (shin bone), stabilizing the knee joint and distributing forces across it. A bucket handle tear is a type of longitudinal tear where the inner rim of the meniscus separates from the main body, running parallel to the circumference of the cartilage. This tear creates a flap of tissue that is still attached at both ends (anterior and posterior horns) but is otherwise free to move.
The injury gets its name because the detached inner fragment displaces, or flips, into the center of the knee joint (the intercondylar notch), resembling the handle of a bucket. This displacement makes the tear unstable, causing mechanical interference within the joint. Bucket handle tears are more frequently observed in the medial meniscus, which is less mobile than the lateral meniscus. The displaced fragment physically obstructs the normal rolling and gliding motion of the knee bones.
Recognizing the Injury
A bucket handle tear typically causes acute and pronounced symptoms that distinguish it from a milder meniscal injury. The most characteristic symptom is the knee “locking” or “catching,” which is a direct result of the displaced meniscal fragment physically blocking the knee’s movement. This mechanical obstruction often prevents the individual from being able to fully straighten the leg, a symptom called an extension block.
The injury is usually accompanied by severe, sharp pain, often localized along the joint line where the tear occurred. Swelling, or effusion, in the knee joint typically develops in the hours following the injury. Patients may also report hearing a distinct “pop” at the moment of injury, followed by a feeling of instability or the knee “giving way” during weight-bearing activities.
Diagnosis and Initial Assessment
Assessment begins with a detailed history and physical examination. Tenderness along the joint line is a common finding. Specific maneuvers, such as the McMurray test, are often performed to identify a meniscal tear by applying rotational force, which can elicit pain or a palpable click as the torn cartilage is trapped between the femur and tibia.
While physical tests are helpful, definitive diagnosis relies on medical imaging. X-rays are used initially to rule out bone fractures, but they cannot visualize soft tissues. Magnetic Resonance Imaging (MRI) is the test of choice because it provides detailed images of the knee’s internal structures. MRI confirms the presence, type, and exact location of the tear, often revealing the displaced fragment in the intercondylar notch through specific signs like the “double PCL sign.”
Repairing the Tear
Surgical intervention is the standard treatment for a displaced bucket handle tear because the loose fragment mechanically locks the knee and will not heal on its own. The procedure is typically performed arthroscopically, using small incisions and specialized tools to visualize and work within the joint. The decision to repair the tear or remove the torn segment is based on several factors, including the tear’s location, the patient’s age, and the quality of the meniscal tissue.
Meniscal repair is the preferred option, as it preserves the entire structure, which is crucial for the long-term health of the knee joint and preventing future arthritis. Repair is most successful when the tear is located in the outer third of the meniscus, known as the red zone, which has a good blood supply and a higher potential for healing. The surgeon will use sutures or specialized fixation devices to stitch the torn piece back to the main body of the meniscus.
If the tear is in the inner, avascular zone (white zone) or the tissue is severely damaged, the surgeon may perform a partial meniscectomy, removing only the unstable fragment. While meniscectomy allows for a faster initial recovery, it is generally avoided because removing meniscal tissue increases stress on the joint surface, raising the risk of osteoarthritis over time. Following surgery, a structured physical therapy program is necessary to restore strength and range of motion.