As the technology of three-dimensional (3D) printing becomes more refined and accessible, multiple applications of its use are becoming more commonplace in upper extremity surgery. 3D-printed models ...have been beneficial in preoperative planning of complex cases of acute trauma or malunions, contributing to spatial understanding or even contouring of implants. Custom guides can also be created to assist intraoperatively with precise placement of osteotomies or arthroplasty implants. Finally, custom 3D implants have been described for cases of bone loss in the upper extremity. This can be for relatively small gaps after malunion correction or extensive defects, typically for trauma or tumor. Articular defects can also be addressed with this technology, although special considerations should be given to the implant design and longevity in these situations. Because of the relatively recent nature of 3D implants, long-term data are lacking. However, they show great promise in an expanding range of challenging clinical indications.
Complex glenoid bone loss and deformity present a challenge for the shoulder arthroplasty surgeon. Eccentric reaming, bone grafting, augmented glenoid components, and salvage hemiarthroplasty are ...common strategies for managing these patients. The glenoid vault reconstruction system (VRS; Zimmer-Biomet) is a novel solution for both primary and revision arthroplasty using a custom glenoid baseplate. We hypothesized that patients undergoing reverse shoulder arthroplasty (RSA) with VRS would have acceptable short-term outcomes and complication rates.
Patients who underwent RSA with VRS for severe glenoid deformity or bone loss by one of 4 board-certified, fellowship-trained shoulder and elbow surgeons at 3 academic tertiary referral centers between September 2015 and November 2018 were eligible for inclusion. Patient data were obtained via medical record review and telephone questionnaires. The Numeric Pain Rating Scale (NPRS), Single Assessment Numeric Evaluation (SANE), American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Penn Shoulder Scores, and range of motion (ROM) measurements were obtained pre- and postoperatively. Radiographs were reviewed at final follow-up for evidence of component loosening or hardware failure. Any complication was documented. Outcomes were compared using Wilcoxon signed-rank tests with P <. 05 considered significant.
Twelve shoulders (11 patients) were included with a mean age of 68 years; 7 were primary arthroplasties and 5 were revisions. At an average follow-up time of 30 months, median improvement in NPRS score was 7 points, SANE score 43%, ASES score 45 points, and Penn Shoulder Score 49 points. There were statistically significant improvements in median ROM measurements (forward elevation 20°, external rotation 40°, internal rotation 2 spinal levels). At final follow-up, all implants were radiographically stable without loosening. There were no complications.
This study demonstrates that RSA using the custom VRS glenoid implant is a safe and effective technique addressing complex glenoid deformity or bone loss in both primary and revision settings. At short-term follow-up, all patient-reported outcomes and ROM measures improved significantly, and there were no complications. Future work should determine mid- and long-term outcomes, preferably in a prospective manner with defined patient populations.
Periarticular osseous defects pose a challenge when considering arthrodesis. Failure to restore the cubic content of bone can result in shortening and malalignment, as well as subsequent ...biomechanical issues. This study reports on 12 patients treated with patient-specific 3-D printed (7) and prefabricated titanium trusses (5). Twelve consecutive patients were treated for osseous defects of the forefoot, hindfoot, and ankle with patient-specific, 3D printed or prefabricated manufacturer titanium trusses. Seven were customized, patient-specific 3D printed trusses (4WEB, Frisco, Texas) and 5 were prefabricated manufacturer titanium trusses. All patients had a minimum of 6 months of clinical and radiographic follow-up. and no patients were lost to follow-up. Seven of the 12 patients had a computed tomography (CT) scan performed following surgery. Successful limb or ray salvage was achieved in 11 of 12 patients (91.7%). Six of 7 patients (85.7%) with a postoperative CT scan, went on to complete radiographic consolidation across all arthrodesis sites. The remaining 5 patients showed complete consolidation across the arthrodesis sites on plain film radiographs. Complications included one patient with a residual midfoot deformity that required a subsequent midfoot osteotomy in order to obtain a plantigrade foot following successful tibiotalocalcaneal (TTC) arthrodesis, and a below knee amputation in one patient who underwent revision TTC arthrodesis to salvage avascular necrosis of the talus that developed following the index procedure. Eleven of 12 patients undergoing arthrodesis demonstrated successful union with both customized, patient-specific 3D printed and prefabricated manufacturer titanium trusses on CT scans or radiographs. The average follow-up was 14 months. Reports on traditional methods of addressing periarticular defects in patients requiring arthrodesis show mixed results and relatively high complication rates. Custom, 3D printed and prefabricated titanium truss technology offers an alternative to traditional methods for large, periarticular osseous defects.
Treatment of large osseous defects remains a difficult surgical challenge. Autografts and allografts have been known to undergo late collapse, because these options are not specifically designed to ...withstand the high loads of the foot and ankle. The inability to achieve the correct shape for reconstruction further limits their application. Large osseous defects will result during salvage after failed Lapidus bunionectomy, explantation of failed total ankle replacements, and nonunion of Evans calcaneal osteotomy. Each of 3 patients received a 4WEB custom 3-dimensional (3D) titanium truss implant (Patient Specific Custom Implant; 4WEB Medical, Inc., Frisco, TX) for reconstruction. The mean follow-up period was 17.33 ± 3.51 months. Significant improvement was seen in pain, with a successful return to activities of daily living. The 12-month postoperative computed tomography findings demonstrated incorporation of the implant to the surrounding cortical and cancellous bone. No signs of delayed complications, such as stress shielding or implant failure, were found. This is the first case series to describe the use of a custom 3D-printed titanium truss implant to successfully contribute to reconstruction in the setting of failed elective foot and ankle surgery. This technology might play an important role in limb salvage of osseous defects that would otherwise require bone block arthrodesis with structural allograft or autograft bone.
The aim of this study was to evaluate polyetheretherketone (PEEK) as a patient-specific implant (PSI) material in maxillofacial reconstructive surgery.
The retrospective study included a cohort of 24 ...patients who underwent maxillofacial surgery using PEEK PSIs. Each patient underwent preoperative multislice computed tomography (CT) with 0° tilt of gantry. Based on the CT scan, the PEEK PSIs were planned and manufactured using three-dimensional (3D) modeling and computer-aided design/computer-aided manufacturing (CAD/CAM) techniques. All procedures were performed under general anesthesia. Implants were placed intraorally, extraorally or through subciliary, transconjuctival or coronal incisions.
In 22 of 24 cases, the PEEK PSI fit well without adjustments. Although the fit to the surrounding bone was perfect in almost all of the cases, the outer contour of the PSI was modified in nine cases before fixation. However, intraoperative implant modification did not affect the infection rate. In two cases, postoperative wound dehiscence and infection needed additional treatment and healed without removal of the implants.
The follow-up data in this study showed good outcomes with reliable results for PSI made of PEEK in the maxillofacial region.
Three‐dimensional (3D) printing is used to manufacture custom acetabular cups to treat patients with massive acetabular defects. There is a risk of defects occurring in these, often in the form of ...structural voids. Our aim was to investigate the presence of voids in commercially available cups. We examined 12, final‐production titanium custom acetabular cups, that had been 3D‐printed by six manufacturers. We measured their mass, then performed micro‐computed tomography (micro‐CT) imaging to determine their volume and density. The micro‐CT data were examined for the presence of voids. In cups that had voids, we computed (1) the number of voids, (2) their volume and the cup volume fraction, (3) their sphericity, (4) size, and (5) their location. The cups had median mass, volume, and density of 208.5 g, 46,471 mm3, and 4.42 g/cm3, respectively. Five cups were found to contain a median (range) of 90 (58–101) structural voids. The median void volume and cup volume fractions of cups with voids were 5.17 (1.05–17.33) mm3 and 99.983 (99.972–99.998)%, respectively. The median void sphericity and size were 0.47 (0.19–0.65) and 0.64 (0.27–8.82) mm, respectively. Voids were predominantly located adjacent to screw holes, within flanges, and at the transition between design features; these were between 0.17 and 4.66 mm from the cup surfaces. This is the first study to examine defects within final‐production 3D‐printed custom cups, providing data for regulators, surgeons, and manufacturers about the variability in final print quality. The size, shape, and location of these voids are such that there may be an increased risk of crack initiation from them.
A 28-year-old female presented with a slowly enlarging, left cheek mass over two years. She underwent neuroimaging and was found to have a well-defined, low attenuating lesion with thickened vertical ...trabeculation of the left zygoma, consistent with intraosseous hemangioma. To minimize the risk of severe intraoperative hemorrhage, the patient underwent embolization of the mass by neuro-interventional radiology two days prior to resection. The patient subsequently underwent a left anterior orbitotomy and partial zygoma resection followed by reconstruction of the lateral orbit with a custom porous polyethylene zygomaxillary implant. The postoperative course was uneventful with a good cosmetic outcome.
The challenge of surgical treatment of hindfoot collapse can be exacerbated by host conditions. Many patients with neuropathy, Charcot joint, or end-stage arthritis that undergo tibiotalocalcaneal ...(TTC) fusion with bulk allograft progress to nonunion and often require amputation. 3D-printed implants may improve outcomes within this population, but long-term outcomes of these implants have not yet been reported. This study reports mid-term outcomes of patients with Charcot arthropathy or end-stage arthritis who received 3D-printed titanium cage and dynamic hindfoot fusion nail combination fixation for limb salvage.
This study was a retrospective review of consecutive patients who underwent hindfoot arthrodesis with a combination of patient-specific 3D-printed titanium cage and dynamic hindfoot fusion nail by a single surgeon at a single institution. The primary outcome was to establish the safety of the 3D-printed cage in a medically complicated population. The secondary outcome was to evaluate the efficacy of the 3D-printed cage, as evaluated by patient-reported pain score, ambulation status, and satisfaction. Deformity correction was evaluated by radiograph.
This study evaluated 13 cases with at least one year follow-up. Mean follow-up was 3.72 years (range 2.67-4.60 years). As of the most recent follow-up, 11 of 13 cages remain implanted, with two cages having been explanted in the setting of amputations indicated by conditions unrelated to the cage itself. Patients reported a mean pre-operative NRS pain of 6.6 ± 2.9 points. At the last follow-up, mean NRS pain was 2.0 ± 1.7 points. Pre-operatively, six of 13 patients reported the ability to ambulate independently without an assistive device. Post-operatively, 11 of 13 patients were able to ambulate independently.
The results demonstrate no implant-related complications and promising outcomes in terms of fusion, deformity correction, and patient satisfaction, which are especially remarkable in the setting of Charcot arthropathy.
PDF
