Enhanced Biomechanical Performance of a Modern Polyester Surgical Mesh for Extensor Mechanism Reconstruction in Total Knee Arthroplasty

Synthetic Ligament-Assisted Functional Soft-Tissue Reconstruction in Tumor-Related Proximal Femoral Replacements

BACKGROUND

Soft-tissue functional reconstruction is important for restoring hip function in proximal femoral replacement for tumor resection. This study evaluated the functional outcome and postoperative complications of a specific synthetic ligament for soft-tissue functional reconstruction in proximal femoral replacement for tumor resection.

METHODS

This cohort included 80 patients (40 men and 40 women, mean age, 40 years (range, 10 to 79)) who had benign invasive tumors (n = 13), primary malignant bone tumors (n = 40), or bone metastases (n = 27). Patients' medical records, imaging files, surgical details, and postoperative pathological diagnoses were collected. Tumor staging was performed with the Enneking staging criteria. Lower limb and hip functions were assessed using the Musculoskeletal Tumor Society scoring system and Harris Hip score, respectively.

RESULTS

Mean postoperative Musculoskeletal Tumor Society and Harris Hip scores were 27 (range, 24 to 30) and 90 (range, 76 to 97), respectively, indicating satisfactory range of motion and stability. Trendelenburg gait was observed in 3 osteosarcoma patients (3.8%), and 6 patients showed unequal lower-limb lengths. Reoperations occurred in 5 cases, including 3 cases of deep vein thromboses and 1 case each of giant cell granuloma and periprosthetic infection. There were 27 patients who had bone metastases who did not require reoperation.

CONCLUSIONS

The synthetic ligament reconstruction of the hip with proximal femoral replacement for tumor resection was associated with improved outcomes. Its implementation exhibits the potential to reduce postoperative incidences of hip dislocation and periprostheses infection, thereby warranting its prospective clinical application.

Primary sternal tumour resection and reconstruction with LARS mesh-bone cement sandwich by 3D-printing: Case reports

Background: There are many reconstruction methods after sternal tumor resection, but the method that LARS mesh combines with bone-cement has not been reported. Case report: A 54-year-old female patient and a 55-year-old male patient admitted to our department all presented with sternum masses, but neither presented with respiratory disorders. In women with limited manubrium sternum lesions, we resected the manubrium sternum completely. In men with sternal lesions, we removed part of the sternum and part of the sternocostal joint. The patients recovered well after surgery, and there were no respiratory complications and no tumor recurrence during the 1-year follow-up respectively. Conclusion: We report two cases of sternal defect repair using LARS mesh combined with bone cement. This method is safe and stable, and can achieve satisfactory results.

Therapy of chronic extensor mechanism deficiency after total knee arthroplasty using a monofilament polypropylene mesh

Introduction

Lesions of the quadriceps or patellar tendon after total knee arthroplasty (TKA) are a rare but serious complication which, if left untreated, can lead to loss of function of the knee joint. While acute and subacute extensor mechanism disruptions may have several causes, chronic deficiencies are often related to multiple prior revision surgeries for joint infection or aseptic TKA failure. Up to date, biological allograft reconstruction showed unsatisfying results. The use of a monofilament polypropylene mesh is a promising approach for this pathological condition. The aim of the present study was to evaluate clinical, functional and patient reported outcomes of this procedure in patients with chronic extensor mechanism deficiency.

Materials and Methods

Twenty-eight patients with chronic extensor mechanism deficiency (quadriceps tendon rupture n = 9, patellar tendon rupture n = 19) after TKA were included in this retrospective study. None of the patients were lost to follow-up. Surgical reconstruction was performed at one institution between 2014 and 2020 with a monofilament polypropylene mesh (Marlex Mesh, Bard, Murray Hill, USA). The mean age at the time of surgery was 69 years. Patients presented with a mean BMI of 33 kg/m². The mean follow-up period was 23 months.

Results

The 2-year survivorship free of mesh revision was 89% [95% confidence interval (CI): 75% to 100%]. Three patients (11%) had to undergo revision because of mechanical mesh failure and received another polypropylene mesh. No further revisions were performed thereafter. Flexion was 87° (range, 30–120°) on average. The majority of patients (75%, 21/28) had a full active extension. The mean active extension lag after surgery was 4 degrees (range, 0–30°).

Discussion

We observed a substantial improvement of extensor mechanism function. The majority of patients had full extension and showed good clinical results. A failure rate of over 50% has been published for alternative procedures. Thus, the use of the described augmentation technique represents a reasonable treatment option for chronic extensor mechanism disruptions of the patellar tendon as well as the quadriceps tendon after total knee arthroplasty. However, there might be a potentially higher risk for infection persistence in periprosthetic joint infection cases due to the presence of a foreign material.