Comparison of 3D computer-assisted planning with and without patient-specific instrumentation for severe bone defects in reverse total shoulder arthroplasty.

BACKGROUND: Preoperative planning is an integral aspect of managing complex deformity in reverse shoulder arthroplasty (RSA). The purpose of this study was to compare the success of patient-specific instrumentation (PSI) and 3D computer-assisted planning with standard instrumentation (non-PSI) in achieving planned corrections of the glenoid among patients undergoing RSA with severe bony deformity requiring glenoid bone grafts. METHODS: A retrospective case-control study was performed, including all patients that underwent RSA with combined bone grafting procedures (BIO-RSA or structural bone grafting) for severe glenoid deformity by a single study between June 2016 and July 2023. Patients were required to have preoperative and postoperative CT scans as well as preoperative 3D planning performed for inclusion. Patients were divided into two groups based on the use of 3D computer-assisted planning with or without PSI (PSI vs. non-PSI). The corrected inclination and version were measured by two separate reviewers on preoperative and postoperative 2D CT scans and compared to their corresponding preoperative planning goals utilizing bivariate analyses. RESULTS: We identified 45 patients that met our inclusion criteria (22 PSI and 23 non-PSI). Preoperative inclination (mean ± SD) (PSI 10.12° ± 15.86°, non-PSI 9.43° ± 10.64°; P = .864) and version (PSI -18.78° ± 18.3°, non-PSI -17.82° ± 11.49°; P = .835) measurements were similar between groups. No significant differences in the mean deviation (error) between the postoperative and planned inclination (PSI 5.49° ± 3.72; non-PSI 6.91° ± 5.05; P = .437) and version (PSI 8.37° ± 5.7; non-PSI 5.37° ± 4.43; P = .054) were found between groups. No difference in the rate of outliers (>10° error) was noted in inclination (P = .135) or version (P = .445) between groups. Greater planned version correction was correlated with greater error when PSI was utilized (PSI r = 0.519, P = .013; non-PSI r = 0.362, P = .089). CONCLUSION: Both PSI and 3D computer-assisted planning without PSI (non-PSI) appear to be useful techniques to achieve version and inclination correction among patients undergoing RSA with severe glenoid deformity required glenoid bone grafting with no clear superiority of one method over the other. Surgeons should be aware that when utilizing PSI, slightly greater error in achieving version goals may occur as version correction is increased.

Patient-specific instrumentation improved axial alignment of the femoral component, operative time and perioperative blood loss after total knee arthroplasty.

PURPOSE: The purpose of the present study was to compare patient-specific instrumentation (PSI) with standard instrumentation (SI) in patients undergoing total knee arthroplasty (TKA). PSI is hypothesized to have advantages with respect to component alignment; number of outliers (defined as alignment > 3° from the target alignment); operative time; perioperative blood loss; and length of hospital stay. This new surgical technique is expected to exhibit superior performance. METHODS: A total of 23 randomized controlled trials (RCTs) involving 2058 knees that compared the clinical outcomes of TKA between PSI and SI were included in the present analysis; these RCTs were identified via a literature search of the PubMed, Embase, and Cochrane Library databases through March 1, 2018. The outcomes of interest included coronal, sagittal and axial component alignment (presented as the angle of deviation from the transcondylar line); number of outliers; operative time; perioperative blood loss; and length of hospital stay. RESULTS: There was a significant difference in postoperative femoral axial alignment between PSI and SI patients (95% CI - 0.71 to - 0.21, p = 0.0004, I2 = 48%). PSI resulted in approximately 0.4° less deviation from the transcondylar line than SI. Based on our results, PSI reduced operative time by a mean of 7 min compared with SI (95% CI - 10.95 to - 3.75, p < 0.0001, I2 = 78%). According to the included literature, PSI reduced perioperative blood loss by approximately 90 ml compared with SI (95% CI - 146.65 to - 20.18, p = 0.01, I2 = 74%). We did not find any differences between PSI and SI with respect to any other parameters. CONCLUSIONS: PSI has advantages in axial alignment of the femoral component, operative time, and perioperative blood loss relative to SI. No significant differences were found between PSI and SI with respect to alignment of the remaining components, number of outliers, or length of hospital stay. LEVEL OF EVIDENCE: Therapeutic study (systematic review and meta-analysis), Level I.

Does computer-assisted navigation improve baseplate screw configuration in reverse shoulder arthroplasty? A systematic review and meta-analysis of comparative studies.

Introduction: Navigation technologies have improved accuracy and precision in positioning glenoid components during shoulder arthroplasty. The influence of navigation on baseplate screw placement has not been independently investigated. This study aimed to evaluate and synthesize the best scientific evidence on the influence of intraoperative navigation on the length and number of screws for primary baseplate fixation in reverse total shoulder arthroplasty procedures. Methods: In August 2022, PubMed, Scopus, and Embase databases were accessed. We analyzed the screw purchase length, the number of screws required for the fixation of the baseplate, and the proportion of cases fixed with two screws in all clinical trials, comparing navigation to standard instrumentation for reverse shoulder arthroplasty. Following an evaluation of the heterogeneity of the studies, DerSimonian-Laird random-effects models were utilized to merge data from separate studies. Results: The systematic search revealed a total of 2034 articles. After excluding duplicates and irrelevant studies, 633 shoulder arthroplasties from 6 trials were included in the analysis. The pooled mean difference in screw purchase length was 5.839 mm (95 %CI 4.496 to 7. 182) in favor of navigation (P < .001). In addition, significant differences were also found in the number of screws per case (- 0.547, 95 %CI -0.890 to -0.203, P = .002) and in the proportion of cases fixed with two screws (Odds Ratio 3.182 95 %CI 1.057 to 9.579, P = .040) in favor of the navigation group. Conclusions: Intraoperative navigation improves the baseplate screw placement, allowing for a greater screw purchase length and fewer screws to achieve primary fixation of the glenoid component during reverse shoulder arthroplasty. It is unclear whether these improvements will increase the longevity of the prosthesis or the clinical outcomes of the patients.

Direct superior approach with standard instrumentation for total hip arthroplasty: safety and efficacy in a prospective 200-case series.

INTRODUCTION: Direct Superior Approach (DSA) is a muscle sparing approach for total hip arthroplasty (THA) implemented using special instrumentation. There is a lack of information in the literature concerning DSA with standard instrumentation. MATERIALS AND METHODS: 238 patients were recruited for primary THA by a single surgeon from January 2016 until May 2017. 209 patients underwent THA through DSA approach with non-offset acetabular reamers and femoral broaches. We evaluated accuracy of implantation, complications and early functional results. Independent orthopaedic surgeons performed the clinical and radiographic assessments. RESULTS: 200 patients were followed for a year. 3 different implants were used. No sciatic nerve palsies, hip dislocations or fractures were recorded. There was one acute deep and superficial wound infection. The mean functional score was significantly improved at all follow-ups (p < 0.001). 97% of stems were inserted into the neutral coronal and 96% in neutral sagittal alignment. All cups fell within a safe zone of inclination and 91% of anteversion. 2 hips demonstrated heterotopic ossification, Brooker class I. Obese patients had no increased risk of complications. CONCLUSIONS: DSA with standard instrumentation is safe and efficacious for THA. It offers fast recovery and facilitates correct implantation of different implants, can be useful even for hip dysplasia and obese patients with minimal complication rates.

The impact of custom cutting guides on patient satisfaction and residual symptoms following total knee arthroplasty.

BACKGROUND: Custom cutting guides (CCGs) in total knee arthroplasty (TKA) use preoperative three-dimensional (3-D) imaging to manufacture cutting blocks specific to a patient's anatomy. The purpose of this study was to evaluate the impact of CCGs versus standard intramedullary and extramedullary guides on patient-reported satisfaction and residual symptoms following TKA. METHODS: A retrospective, multicenter study was performed to compare a magnetic resonance imaging-based CCG system versus standard instrumentation. All patients received the same, cemented, fixed-bearing, cruciate-retaining component, and had a primary diagnosis of osteoarthritis. Data was collected by an independent, third party survey center blinded to surgical technique that administered telephone questionnaires assessing patient satisfaction and symptoms. Patient age, gender, minority status, education level, income, length of follow-up, and pre-arthritic UCLA scores were considered potential confounders and accounted for using multivariate logistic regression analyses. RESULTS: 448 patients (107 CCGs, 341 standard) were successfully interviewed. At a mean follow-up of threeyears, there was no difference in percentage of patients reporting their knee to feel "normal" (74% CCG versus 78% standard, p=0.37). Residual symptoms including knee stiffness (37% CCG versus 28% standard, p=0.08) and difficulty getting in and out of car (34% CCG versus 30% standard, p=0.40) remained high. Multivariate regression analyses demonstrated no differences between the two cohorts for both patient-reported satisfaction and residual symptoms (odds ratios 0.72 to 1.48; p=0.10 to 0.81). CONCLUSION: When interviewed by an independent, blinded third party, the use of CCGs in TKA did not improve patient-reported satisfaction or residual symptoms versus the use of standard alignment guides.