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. 2023 Dec 8;23(1):369.
doi: 10.1186/s12893-023-02281-3.

Early outcomes of total hip arthroplasty using point-of-care manufactured patient-specific instruments: a single university hospital's initial experience

Hieu Pham Trung  1   2   3 , Nang Vo Sy Quyen  1   2   3 , Nam Vu Tu  2   3 , Dung Tran Trung  2   3 , Toan Duong Dinh  4
Affiliations

Early outcomes of total hip arthroplasty using point-of-care manufactured patient-specific instruments: a single university hospital's initial experience

Hieu Pham Trung et al. BMC Surg. .

Abstract

Background: The use of 3D-printed Patient-Specific Instruments (PSI) has been investigated to enhance the postoperative functional results in total hip arthroplasty (THA) and has been recognized as an innovative approach for the optimal alignment of hip implant components. Point-of-care production is gradually becoming the norm for PSI manufacturing. The purpose of this article is to assess the accuracy and safety of PSI for total hip arthroplasty performed at the point-of-care in Vietnam.

Methods: 34 THA cases were assessed in this prospective study. A template for the size and orientation of the implant and the design of the PSI was generated using data from preoperative 3D computed tomography (CT) scanning of the lower limb. The principal surgeon determined the implants' position and PSI design directly using the software. The PSI is then produced using a 3D-compatible resin printer in our manufacturing hospital. The PSI, consisting of an acetabulum and a femoral component placed press-fit on the bony surface, guided surgeons to precisely ream the acetabulum and cut the femoral neck according to the pre-planned plane. Postoperative CT scanning was obtained and superimposed onto the 3D model of the implant to evaluate the accuracy of the procedure by comparing the orientation values of the cup and the alignment of the stem between the planned and the actual results. Intra- and postoperative clinical parameters of surgery, including surgical time, intra-operative blood loss, complications, and the first ambulation, were also recorded to evaluate the safety of the surgery.

Results: The preparation for PSI required an average of 3 days. 94% of cup size and 91% of stem size were correctly selected. The mean values of postoperative inclination and anteversion were 44.2° ± 4.1° and 19.2° ± 5.6°, respectively. 64.7% of cases deviated from planned within the ± 50 range and 94.1% within the ± 10° range. There was no significant statistical difference between the planned and the achieved values of stem anteversion, osteotomy height, and leg length discrepancy (p > 0.05). The average surgical time was 82.5° ± 10.8 min, and the intraoperative blood loss was estimated at 317.7° ± 57.6 ml. 64.7% of patients could walk on the day of surgery. There were no complications reported.

Conclusions: The point-of-care manufactured PSI is a useful solution for improving the accuracy of total hip arthroplasty surgery, especially in restoring implant orientation and reducing leg length discrepancy. However, long-term clinical follow-up evaluation is needed to confirm the efficacy and safety of this approach.

Keywords: 3D Printing; PSI; Patient-specific instrument; Point-of-care manufacturing; THA; Total hip arthroplasty.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Hip joint implants measurements on the surgical templating software parameters that can be evaluated include anatomical indices of the hip joint, cup and stem size and orientation
Fig. 2
Fig. 2
Design and intra-operative use of the femoral neck cutting guide. The PSI has a slotted shape designed to help define the femoral neck cut plane and the lateral edge to create a diagonal orientation to determine stem anteversion
Fig. 3
Fig. 3
Design and intra-operative use of the Acetabular cup PSI. A: Part A is designed to be pressed fit to the acetabulum joint surface and locates 2 pins marked on the superior-posterior rim of the acetabulum; B: Part B is designed to be placed on the 2 pins marked by part A, and helps to attach 2 guiding pins that connect to part C; C: Part C is designed to connect with guiding pins to accurately orient the reamer handle along the center cup axis
Fig. 4
Fig. 4
Evaluation of cup orientation on post-operative CT scan by Medicad. Using the method of overlaying the image of implant data available in the software onto the actual implant, it is possible to measure the postoperative indicators and compare them with the templating index
Fig. 5
Fig. 5
Scatter plot of achieved cup orientation within 50 and 100 range of deviation from template
See this image and copyright information in PMC

References

    1. D’lima DD, et al. The effect of the orientation of the acetabular and femoral components on the range of motion of the hip at different head-neck ratios. JBJS. 2000;82(3):315–21. doi: 10.2106/00004623-200003000-00003. - DOI - PubMed
    1. Callanan MC, et al. The John Charnley Award: risk factors for cup malpositioning: quality improvement through a joint registry at a tertiary hospital. Clin Orthop Relat Research®. 2011;469:319–29. doi: 10.1007/s11999-010-1487-1. - DOI - PMC - PubMed
    1. Hassan DM, et al. Accuracy of intraoperative assessment of acetabular prosthesis placement. J Arthroplast. 1998;13(1):80–4. doi: 10.1016/S0883-5403(98)90079-1. - DOI - PubMed
    1. Moralidou M, et al. Three-dimensional pre-operative planning of primary hip arthroplasty: a systematic literature review. EFORT open Reviews. 2020;5(12):845. doi: 10.1302/2058-5241.5.200046. - DOI - PMC - PubMed
    1. Kumar P, et al. Application of 3D Printing in hip and knee arthroplasty: a narrative review. Indian J Orthop. 2021;55(Suppl 1):14–26. doi: 10.1007/s43465-020-00263-8. - DOI - PMC - PubMed