Is three-dimensional–printed custom-made ultra-short stem with a porous structure an acceptable reconstructive alternative in peri-knee metaphysis for the tumorous bone defect?

Abstract

Background Long-lasting reconstruction after extensive resection involving peri-knee metaphysis is a challenging problem in orthopedic oncology. Various reconstruction methods have been proposed, but they are characterized by a high complication rate. The purposes of this study were to (1) assess osseointegration at the bone implant interface and correlated incidence of aseptic loosening; (2) identify complications including infection, endoprosthesis fracture, periprosthetic fracture, leg length discrepancy, and wound healing problem in this case series; and (3) evaluate the short-term function of the patient who received this personalized reconstruction system. Methods Between September 2016 and June 2018, our center treated 15 patients with malignancies arising in the femur or tibia shaft using endoprosthesis with a 3D-printed custom-made stem. Osseointegration and aseptic loosening were assessed with digital tomosynthesis. Complications were recorded by reviewing the patients’ records. The function was evaluated with the 1993 version of the Musculoskeletal Tumor Society (MSTS-93) score at a median of 42 (range, 34 to 54) months after reconstruction. Results One patient who experienced early aseptic loosening was managed with immobilization and bisphosphonates infusion. All implants were well osseointegrated at the final follow-up examination. There are two periprosthetic fractures intraoperatively. The wire was applied to assist fixation, and the fracture healed at the latest follow-up. Two patients experienced significant leg length discrepancies. The median MSTS-93 score was 26 (range, 23 to 30). Conclusions A 3D-printed custom-made ultra-short stem with a porous structure provides acceptable early outcomes in patients who received peri-knee metaphyseal reconstruction. With detailed preoperative design and precise intraoperative techniques, the reasonable initial stability benefits osseointegration to osteoconductive porous titanium, and therefore ensures short- and possibly long-term durability. Personalized adaptive endoprosthesis, careful intraoperative operation, and strict follow-up management enable effective prevention and treatment of complications. The functional results in our series were acceptable thanks to reliable fixation in the bone-endoprosthesis interface and an individualized rehabilitation program. These positive results indicate this device series can be a feasible alternative for critical bone defect reconstruction. Nevertheless, longer follow-up is required to determine whether this technique is superior to other forms of fixation.

Novel axial compressive endoprosthesis ACE can enhance metaphyseal fixation and facilitate osseointegration: A biomechanical study

“…Efforts to improve metaphysis fixation can be summarized into two categories. One is auxiliary fixation structure to enhance reconstruction, the other is a surface modification to achieve osseointegration ( Bini et al, 2000 ; Dieckmann et al, 2014 ; Stevenson et al, 2017 ; Bernthal et al, 2019 ; Wang et al, 2021 ).…”

“…Efforts to improve metaphysis fixation can be summarized into two categories. One is auxiliary fixation structure to enhance reconstruction, the other is a surface modification to achieve osseointegration (Bini et al, 2000;Dieckmann et al, 2014;Stevenson et al, 2017;Bernthal et al, 2019;Wang et al, 2021). Stevenson et al (2017) reported that HA (hydroxyapatite) coated extra-cortical plates increased the survivorship of shortcemented-stemmed endoprostheses.…”

“…A hydroxyapatite-coated collar is used in cemented stem fixation to prevent wear particles from entering the medullary cavity ( Cobb et al, 2005 ; Stevenson et al, 2017 ). A 3D-printed stem with a porous structure is designed to achieve long-term osseointegration ( Wang et al, 2021 ). However, there is still no well-established optimal technique for metaphyseal fixation.…”

Intercalary allograft reconstruction following femoral tumour resection: mid- and long-term results and benefits of adding a vascularised fibula autograft

“…The femur is a common site for primary bone tumours, but a diaphyseal location is less common than at the extremities [ 1 ]. Several techniques have been described for reconstruction after extensive diaphyseal femoral resection (> 10 cm) [ 2 ]: biological reconstructions: vascularised autograft [ 3 ], Masquelet’s induced membrane [ 4 ], allograft [ 5 ], combined graft [ 6 ], or even distraction osteogenesis or transport techniques [ 7 ], and finally prosthetic reconstructions using segmental prostheses, or custom reconstructions [ 8 – 11 ]. Some other innovative biologic techniques are also described but with a short follow-up on a small cohort [ 12 ].…”

“…Moreover, long-term survival is questionable with these implants. Although they allow early weight-bearing, the rate of complications is high (up to 60%), consisting primarily of infections, fractures, and loosening [ 11 , 13 ]. Several authors also report the use of devitalised tumour-bearing bone with interesting results, but with tumour histological analysis potential issues [ 14 – 16 ].…”