The impact of 3-dimensional humeral planning and standard transfer instrumentation on reconstruction of native humeral anatomy for anatomic total shoulder arthroplasty.

BACKGROUND: Preoperative 3-dimensional (3D) computed tomography (CT)-based planning for anatomic total shoulder arthroplasty (TSA) has grown in popularity in the past decade with the primary focus on the glenoid. Little research has evaluated if humeral planning has any effect on the surgical execution of the humeral cut or the positioning of the prosthesis. METHODS: Three surgeons performed a prospective study using 3D-printed humeri printed from CTs of existing patients, which were chosen to be -3, -1, 0, 1, and 3 standard deviations of all patients in a large database. A novel 3D printing process was used to 3D print not only the humerus but also all 4 rotator cuff tendons. For each surgical procedure, the printed humerus was mounted inside a silicone shoulder, with printed musculature and skin, and with tensions similar to human tissue requiring standard retraction and instruments to expose the humerus. Three phases of the study were designed. In phase 1, humeral neck cuts were performed on all specimens without any preoperative humeral planning; in phase 2, 3D planning was performed, and the cuts and implant selection were repeated; in phase 3, a neck-shaft angle (NSA) guide and digital calipers were used to measure humeral osteotomy thickness to aid in the desired humeral cut. All humeri were digitized. The difference between the prosthetic center of rotation (COR) and ideal COR was calculated. The percentage of patients with a varus NSA was calculated for each phase. The difference in planned and actual cut thickness was also compared. RESULTS: For both 3D change in COR and medial to lateral change in COR, use of preoperative planning alone and with standard transfer instrumentation resulted in a significantly more anatomic restoration of ideal COR. The deviations from planned cut thickness decreased with each phase: phase 1: 2.6 ± 1.9 mm, phase 2: 2.0 ± 1.3 mm, phase 3: 1.4 ± 0.9 mm (P = .041 for phase 3 vs. phase 1). For NSA, in phase 1, 7 of 15 (47%) cases were in varus; in phase 2, 5 of 15 (33%) were in varus; and in phase 3, 1 of 15 (7%) cases was in varus (P = .013 for phase 3 vs. phase 1). CONCLUSIONS: Use of preoperative 3D humeral planning for stemless anatomic TSA improved prosthetic humeral COR, whether performed with or without standard transfer instrumentation. The use of an NSA cut guide and calipers to measure cut thickness significantly reduced the percentage of varus humeral cuts and deviation from planned cut thickness.

Influence of backside seating parameters and augmented baseplate components in virtual planning for reverse shoulder arthroplasty.

BACKGROUND: The primary goal of this investigation was to examine the influence of a backside seating percentage variable on volume of reamed bone and contact area in virtual planning for glenoid baseplate placement for reverse total shoulder arthroplasty (RTSA). The secondary goal was to assess how the option of augmented glenoid baseplate components affected reamed volume and cortical contact area of virtually positioned baseplates. METHODS: Nine surgeons virtually planned 30 RTSA cases using a commercially available software system. The 30 cases were chosen to span a spectrum of glenoid deformity. The study consisted of 3 phases. In phase 1, cases were planned with the backside seating percentage blinded and without the option of augmented baseplate components. In phase 2, the backside seating parameter was unblinded. In phase 3, augmented baseplate components were added as an option. Implant version and inclination were recorded. By use of computer-assisted design models, total volume of bone reamed, as well as reamed cortical volume and cancellous volume, was calculated. Total, cortical, and cancellous baseplate contact areas were also calculated. Finally, total glenoid lateralization was calculated for each phase and compared. RESULTS: Mean implant version was clinically similar across phases but was statistically significantly lower in phase 3 (P = .006 compared with phase 1 and P = .001 compared with phase 2). Mean implant inclination was clinically similar across phases but was statistically significantly lower in phase 3 (P < .001). Phase 3 had statistically significantly lower cancellous and total reamed bone volumes compared with phase 1 and phase 2 (P < .001 for all comparisons). Phase 3 had statistically significantly larger cortical contact area, lower cancellous contact area, and larger total contact area compared with phase 1 and phase 2 (P < .001 for all comparisons). Phase 3 had significantly greater glenoid lateralization (mean, 10.5 mm) compared with phase 1 (mean, 7.8 mm; P < .001) and phase 2 (mean, 7.9 mm; P < .001). CONCLUSIONS: Across a wide range of glenoid pathology during virtual surgical planning, experienced shoulder arthroplasty surgeons chose augmented baseplates frequently, and the option of a full-wedge augmented baseplate resulted in statistically significantly greater correction of glenoid deformity, improved total and cortical baseplate contact area, less cancellous reamed bone, and greater glenoid lateralization. Backside seating information does not have a significant impact on how glenoid baseplates are virtually positioned for RTSA, nor does it impact the baseplate contact area or volume of reamed bone.

Computed tomography versus magnetic resonance imaging in high-dose-rate prostate brachytherapy planning: The impact on patient-reported health-related quality of life.

PURPOSE: High-dose-rate (HDR) prostate brachytherapy uses volumetric imaging for treatment planning. Our institution transitioned from computed tomography (CT)-based planning to MRI-based planning with the hypothesis that improved visualization could reduce treatment-related toxicity. This study aimed to compare the patient-reported health-related quality of life (hrQOL) and physician-graded toxicity outcomes of CT-based and MRI-based HDR prostate brachytherapy. METHODS: From 2016 to 2019, 122 patients with low- or intermediate-risk prostate cancer were treated with HDR brachytherapy as monotherapy. Patients underwent CT only or CT and MRI imaging for treatment planning and were grouped per treatment planning imaging modality. Patient-reported hrQOL in the genitourinary (GU), gastrointestinal (GI), and sexual domains was assessed using International Prostate Symptom Score and Expanded Prostate Cancer Index Composite Short Form-26 questionnaires. Baseline characteristics, changes in hrQOL scores, and physician-graded toxicities were compared between groups. RESULTS: The median follow-up was 18 months. Patient-reported GU, GI, and sexual scores worsened after treatment but returned toward baseline over time. The CT cohort had a lower baseline mean International Prostate Symptom Score (5.8 vs. 7.8, p = 0.03). The other patient-reported GU and GI scores did not differ between groups. Overall, sexual scores were similar between the CT and MRI cohorts (p = 0.08) but favored the MRI cohort at later follow-up with a smaller decrease in Expanded Prostate Cancer Index Composite Short Form-26 sexual score from baseline at 18 months (4.9 vs. 19.8, p = 0.05). Maximum physician-graded GU, GI, and sexual toxicity rates of grade ≥2 were 68%, 3%, and 53%, respectively, with no difference between the cohorts (p = 0.31). CONCLUSION: Our study shows that CT- and MRI-based HDR brachytherapy results in similar rates of GU and GI toxicity. MRI-based planning may result in improved erectile function recovery compared with CT-based planning.

Incidence of Suboptimal Applicator Placement and the Resulting Dosimetric Impact in Image-Based Intracavitary Brachytherapy.

AIM: With the advent of computed tomography (CT)-based brachytherapy, it is possible to view the appropriate placement of the applicator within the uterine canal and detect uterine perforation. In this study, the incidence of suboptimal placement of the intracavitary applicator and the resulting dosimetric impact were analyzed and compared with a similar set of ideal applicator placement. MATERIALS AND METHODS: CT datasets of 282 (141 patients) high dose rate brachytherapy insertions between January and April 2016 were analyzed. The target volumes and organs at risk (OAR) were contoured as per the Groupe Européen de Curiethérapie European Society of Therapeutic Radiation Oncology guidelines. The position of the applicator in the uterine cavity was analyzed for each application. RESULTS: The suboptimal insertion rate was 11.7%. There were 26 perforations and 7 subserosal insertions. The most common site of perforation was through the posterior wall of the uterus (42.4%). Fundus perforation and anterior wall perforation were seen in 24.2% and 12.1% of patients, respectively. The average dose to 90% of the target volume (D90 to high-risk clinical target volume) was the highest (9.15 Gy) with fundal perforation. Average dose to 2 cc (D2cc) bladder was highest for fundus perforation (7.65 Gy). The average dose received by 2 cc of rectum (D2cc) was highest (4.49 Gy) with posterior wall perforation. The average D2cc of the sigmoid was highest with anterior perforation (3.18 Gy). CONCLUSION: In order to achieve better local control and to decrease doses to OAR, it is important to perform a technically accurate applicator placement. A cost-effective, real-time image guidance modality like ultrasound is recommended for all insertions to ensure optimal applicator insertion.