What are intra-articular loose bodies and why they threaten knee health

In a remarkable surgical achievement, doctors at Fortis Hospital Shalimar Bagh successfully performed a total knee replacement (TKR) recently on a 65-year-old woman while simultaneously removing 32 intra-articular loose bodies weighing a combined 250 grams, a combination rarely documented in global orthopedic practice.

The patient, who had been struggling with severe knee pain and joint deformity for years, was discharged in stable condition within six days.

The complex surgery was led by Dr. (Prof.) Amite Pankaj Aggarwal, Principal Director and Head of the Fortis Bone and Joint Institute. Pre-operative imaging revealed widespread calcified loose bodies filling the joint cavity. During surgery, 32 lumpy growths were removed, the largest measuring nearly 4 cm, roughly the size of a walnut. All loose bodies were excised prior to the knee replacement, ensuring successful joint reconstruction.

The surgery posed unique challenges. “Before replacing the knee, all loose bodies had to be removed as they could cause locking or damage the implant. Additionally, significant bone defects caused by these bodies had to be reconstructed during the procedure, which increased surgical time,” Dr. Aggarwal added.

What are loose bodies and why are they a problem?

The patient was diagnosed with secondary synovial chondromatosis, a rare joint disorder where cartilage nodules form inside the joint. Unlike common osteoarthritis, which is age-related wear of cartilage, synovial chondromatosis can gradually destroy joint cartilage, restrict movement, and cause repeated locking of the knee.

Dr Aggarwal said: “Synovial chondromatosis is extremely rare. In this case, the joint cavity was packed with 32 loose bodies, some nearly the size of walnuts. The total weight exceeding 250 grams is likely the highest ever reported in a single knee joint.”

Why is this surgery extraordinary?

Removing these loose bodies before performing the knee replacement was critical. If left untreated, they could have damaged the implant or caused further locking. Many had caused bone defects that needed reconstruction during surgery, increasing its complexity and duration.

Dr. Aggarwal added, “Performing a knee replacement in such a compromised joint required meticulous planning and advanced surgical techniques. The patient reported significant pain relief and improved mobility within days.”

Signs you should watch for

Patients may notice locking episodes, restricted movement, or even feel the loose bodies moving within the joint. Untreated, these can accelerate cartilage damage and lead to early arthritis, making later surgery more complicated.

Rising knee problems in India

Knee replacements are becoming more common, with younger patients in their fifties increasingly requiring surgery. Advances in implants and robotic-assisted surgeries have improved outcomes and patient acceptance.