3D-printed glenoid implant reconstruction, after partial scapulectomy for malignant tumors: a case series

PURPOSE

Glenoid tumors are extremely rare, and reconstruction remains very challenging. The aim of this study is to present the clinical and functional outcomes, of a new glenoid reconstruction method using 3-dimensional-printed implant.

METHODS

Four patients with primary glenoid tumors underwent reconstruction using 3-dimensional-printed glenoid implant linked with reverse shoulder arthroplasty. We retrospectively reviewed the clinical and functional outcome, using MSTS and DASH score, as well as complications' rate.

RESULTS

Wide excision was achieved in all patients. No local recurrence or distant metastasis was diagnosed at the follow-up period. The mean MSTS score was 80.5%, and DASH score was 15.2%. According to Hendersons' classification, there were no postoperative complications.

CONCLUSION

The use of 3-dimensional-printed implants, can be a very reliable solution with satisfying clinical and functional outcomes for reconstruction, in patients with musculoskeletal malignancies of the glenoid. Level of evidence IV Treatment Study.

The use of a 3D printed titanium implant for arthrodesis in the management of large osseous defects in the ankle

BACKGROUND

Large osseous defects (LOD) in the ankle occur because of multiple aetiologies. Advancement in 3-dimensional (3D) printing technologies has led to the use of custom implants and instrumentation their management. A 3D printed patient-specific porous titanium cage which allows for peripheral osteo-integration and autogenous bone-grafting could be an ideal implant in these cases.

METHODS

Retrospective review of a multi-centre, multi-surgeon consecutive cohort of patients requiring either TTC or AA for a large osseous defect between June 2019 - August 2020. A custom titanium prosthesis was 3D-printed according to CT measurements for implantation.

RESULTS

Mean follow up was 19.5 months (range 12-24 months). Plain radiographs and CT scans at 12 months confirmed osseointegration (stability) in 11of 13 patients (84%). Two patients developed late infection, one requiring revision surgery.

CONCLUSIONS

3D-Printed titanium implants in the management of LODs in the ankle offer a comparable success rate to other reported procedures, with unlimited geometric possibilities in the design allowing for accurate length correction. Their structural stability may offer an advantage over conventional bone graft techniques and limits the amount of bone-graft required.

LEVELS OF EVIDENCE

LOE III.

Vertebral body replacement using patient-specific three-dimensional-printed polymer implants in cervical spondylotic myelopathy: an encouraging preliminary report

BACKGROUND CONTEXT

Resulting from recent studies that suggest a benefit of implant design on the achievement of fusion and stability in cervical spinal disease management, manufacturing development has increased over the past years. This article attempts to describe how the development of patient-specific implants, which are used during the procedures of anterior cervical corpectomy and vertebral body replacement (VBR), impacts the outcomes of cervical spondylotic myelopathy (CSM) management.

MATERIALS AND METHODS

This prospective clinical study included six patients who were implanted with patient-specific VBR for single-level or multilevel CSM. The following clinical scores were collected: visual analog scale (VAS), modified Japanese Orthopaedic Association (mJOA), Neck Dysfunction Index (NDI), and European myelopathy score (EMS), along with radiological measurements.

RESULTS

Six patients reached a mean follow-up date of 21months (12-24). Angle measurements remained constant during follow-up, including the C2-C7 Cobb angle and the corpectomy Cobb angle. Furthermore, no deformations, such as hyperlordosis or kyphosis, were detected. The anterior height (Ha) and the posterior height (Hp) of the corpectomy segment remained constant (ratio close to 1) with no severe subsidence (>3 mm) at the last follow-up. No height differences were detected between the preoperative and the last follow-up dates, neither for the upper Hp and Ha (0.97±0.09 and 1.00±0.06, respectively) nor for the lower adjacent vertebrate Hp and Ha (0.96±0.04 and 1.02±0.12). The mean mJOA and EMS recovery rates were 60.4% (standard deviation [SD] 20.4) and 77.0% (SD 29.7), respectively, at last the follow-up. An EMS of at least 16 of 18 was observed in 83% (5 of 6) of the patients. We recorded a preoperative NDI score at 47.1% (SD 18.6) that improved to 11.2% (SD 4.1) at the last follow-up (p<.01). The preoperative VAS neck (6.3, range 4-7) and the VAS arm (6.1, range 3- 9) scores improved to 1.3 (range 0-3) and 2.8 (range 0-5), respectively, at the last follow-up.

CONCLUSIONS

This preliminary report suggests a possible benefit of the use of patient-specific implants in CSM treatment. The favorable clinical and radiological outcomes were associated with a correct achievement rate; these are promising elements toward the development of the concept of personalized therapy. Nonetheless, these encouraging results have to be confirmed now with a longer follow-up and a larger cohort.