Total patellectomy with extensor mechanism reconstruction following pathological fracture due to patellar Ewing's sarcoma

A Novel and Effective Surgical Technique for Reconstruction of Extensor Mechanism with Iliotibial Band Tendon Graft After Patellectomy for Primary Patella Tumor

Background

Amongst primary patella tumor Campanacci grade 3 tumor of Giant cell tumor of bone (GCTB) and malignant tumors requires patellectomy. We had a patient with huge recurrent GCTB of patella with involvement of skin. We reconstructed extensor mechanism of Knee with long iliotibial band (ITB) tendon graft.

Material and Methods

After patellectomy, we harvested long ITB graft (length 22 cm; width proximally 6 cm, distally 1.5 cm) through patellectomy wound and small "L" shaped incision proximally. We passed ITB graft from patella tendon and quadriceps tendon in figure of 8 manner and sutured it back to itself and host tendon with fiber Wire and closed both the wounds primarily. We started ROM and quadriceps strengthening in graded manner. We measured functional outcome with Musculoskeletal Tumour Society (MSTS) scoring system.

Results

There were no post-operative complications. At 10 weeks follow up, patient had no extension lag and knee ROM was 90°. At final follow up of 7 months patient regained pre-operative functional status without knee instability. Her MSTS score was 30 and she was disease free.

Conclusion

Reconstruction of extensor mechanism of knee with ITB graft doesn't have donor site morbidity and gives excellent function with graded physiotherapy protocol.

Knee Extensor Apparatus Reconstruction with Allograft after Patellar Resection: A Case Report

Background

The extensor apparatus of the knee can be thought of a chain that transmits the muscular strength developed by the quadriceps muscles to the proximal tibia. This complex is essential to allow the extension of the tibia over the femur, being essential to provide knee mobility and stability. In case of lesions which irreparably damage the patella, such as a locally aggressive bone tumor, it is necessary to restore both the apparatus' anatomical continuity and its strength.

Case report

A 39-years-old Caucasian man with a history of lung carcinoma developed atraumatic swelling and soreness in his left knee. Imaging evidence reported a degeneration of the left patella. We performed an en bloc resection of the patella and the nearby soft tissues of the extensor apparatus. The resulting gap was fulfilled with a massive allograft consisting of a quadriceps tendon, a patella and a patellar ligament. No complication or local recurrences were observed. At the patient's latest follow-up, he did not have any extension lag and quadriceps strength was completely restored.

Conclusion

Massive allografts can represent a reliable alternative for the reconstruction of the patella and the knee extensor apparatus in orthopedic oncology.

Three-dimensional-printed custom-made patellar endoprosthesis for recurrent giant cell tumor of the patella: A case report and review of the literature

BACKGROUND

Giant cell tumor (GCT) is a benign lesion and rarely involves the patella. This disease is characterized by a relatively high recurrence rate after primary treatment. En bloc resection has been a predominant option for recurrent GCT. However, total patellectomy can lead to disruption of the knee. Therefore, exploration of functional reconstruction of the extensor mechanism is worthwhile.

CASE SUMMARY

A 54-year-old woman presented with right knee pain and swelling, and was diagnosed as having a GCT in the patella following curettage and autograft. Medical imaging revealed a lytic and expanded lesion involving the whole patella with focal cortical breaches and pathological fracture. Based on the combination of histological, radiological, and clinical features, a diagnosis of recurrent GCT in the patella was made (Campanacci grade III). After a multidisciplinary team discussion, three-dimensional (3D)-printed custom-made patellar endoprosthesis was performed following en bloc resection for reconstructing the extensor mechanism. The patient was followed for 35 mo postoperatively. No evidence of local recurrence, pulmonary metastasis, or osteoarthritis of the right knee was observed. The active flexion arc was 0°-120°, and no extension lag was detected. A favorable patellar tracking and height (Insall-Salvati ratio 0.93) were detected by radiography.

CONCLUSION

We depict a case of a GCT at the right patella, which was successfully treated by patellectomy and 3D-printed custom-made endoprosthetic replacement. The patella normal reconstruction, the precise-fit articular design, and gastrocnemius flap augmentation could lead to satisfactory knee function and a low rate of complications in the short-term follow-up.