Researchers devise Novel Treatment Strategy for Femoral Neck Unicameral Bone Cysts

Unicameral Bone Cysts (UBCs) are benign lesions often found in children but may persist into adulthood. Femoral neck is one of the most common sites for UBCs, increasing fracture risk in the lower weight-bearing extremity. Due to unclear etiology, the optimal treatment still remains debated. Recently, less invasive procedures have been advocated and introduced for bone tumors.

Jinhong Wang et al proposed a novel minimally invasive approach combining endoscopic curettage with closed centromedullary nail fixation for adult femoral neck UBCs. This technique innovatively merges two minimally invasive procedures, minimizing muscle damage while ensuring complete curettage of the cyst wall membrane under direct endoscopic visualization. The nail fixation provides immediate stability for early mobilization. This method aims to standardize treatment for adult femoral neck UBCs, balancing efficacy with reduced invasiveness.

Surgical Steps: Endoscopic Curettage, Bone Grafting and Intramedullary Nailing of Femoral UBC

A. Patient positioning and portal creation

1. Position the patient supine on a traction table; abduct the contralateral limb for C-arm access.

2. Make a ~2 cm incision starting at the vastus ridge.

3. Under fluoroscopy, insert a guidewire into the centre of the cyst, parallel to the femoral head–neck axis, without penetrating the hip joint.

4. Insert a protection sleeve and create a lateral cortical window using an 11 mm drill bit.

5. Perform initial gross curettage through this window.

6. Make a second ~3 cm proximal incision, approximately 5 cm above the greater trochanter tip.

7. Insert a guidewire through the greater trochanter, aligned with the femoral shaft axis; confirm position on AP and lateral/axial fluoroscopic views.

8. Create the proximal cortical entry window using an 11 mm drill bit or reamer.

B. Endoscopic curettage

1. Insert a 2.7 mm, 30° arthroscope through the distal window with normal saline irrigation.

2. Inspect the cyst cavity systematically.

3. Perform circumferential curettage of the fibrous lining using curettes and forceps.

4. Exchange viewing and working portals as required; use an arthroscopic shaver for residual membranous tissue.

5. Confirm complete removal of the cyst lining endoscopically.

6. Irrigate the cavity thoroughly and send tissue samples for histopathological examination.

C. Intramedullary nail fixation and bone grafting

1. Insert the centromedullary nail over the guidewire to the planned depth.

2. Fill the cyst cavity with synthetic bone graft through the lateral cortical window under fluoroscopic guidance.

3. Insert the guidewire along the femoral neck axis.

4. Insert the blade or lag screw over the guidewire to the appropriate depth.

5. Drill both femoral cortices and insert an appropriately sized bicortical cortical screw for distal locking, as described in the technique.

6. Confirm implant position and cyst filling using fluoroscopy.

7. Close the incisions with interrupted sutures.

For further details on the article refer to:

Endoscopy-Assisted Curettage Together with Centromedullary Nail Fixation Provides a Novel Method to Treat Femoral Neck Unicameral Bone Cyst in Adults

Jinhong Wang et al

Indian Journal of Orthopaedics (2026) 60:1695·1700

https://doi.org/10.1007/s43465-025-01684-z