Keith M. Baumgarten

Introduction: Studies that examine the image-based Rosa robotic knee arthroplasty system in restoring the desired mechanical axis (MA) are rare. The purpose of this study was to measure the accuracy of an image-based robotic knee system in restoring the desired MA. Methods: Inclusion criteria was patients undergoing an imaged-based total knee arthroplasty with preoperative and postoperative long-leg standing radiographs. Six measurements were analyzed: 1) preoperative radiographically-determined MA (PreopRadMA), 2) preoperative industry/software-determined MA (PreopSoftMA), 3) robotically-determined native MA (PreopRobMA), 4) intraoperatively-planned MA (PlanMA), 5) intraoperative MA after-implant-cementation (IntraopMA), and 6) 2-week-postoperative radiographic MA (PostopRadMA). An outlier was defined when there was greater than 3⁰ between MA measurements. Results: There was excellent agreement among preoperative measurements, poor-to-moderate agreements between planned MA and IntraopMA and PostopRadMA, and good-to-excellent agreement comparing IntraopMA with PostopRadMA. The IntraopMA and PostopRadMA deviated from the PlanMA by 1.4±1.1⁰ (4% outliers) and 1.6±1.3⁰ (14% outliers), respectively. The PostopRadMA differed from the IntraopMA by 1.5±1.2⁰ (8% outliers). There were greater differences found in the mean variances and outlier percentages between the 1) PreopRadMA and PreopRobMA (2.8±2.0⁰; p<0.0001; 40% outliers;) and 2) PreopSoftMA and PreopRobMA (3.3±2.2; p<0.0001; 50% outliers) compared to the mean variances and outliers between the PostopRadMA and IntraopMA (1.5±1.2⁰; 8% outliers). There was no difference between the accuracy of the PostopRadMA (1.4±1.3⁰) and the PlanMA (1.6±1.4⁰; p=0.37) or the IntraopMA (1.5±1.2⁰; p=0.63) in varus compared to valgus knees. Conclusions: The mean differences in planned MA with IntraopMA and PostopRadMA were less than 2⁰. Intraoperative measurements may be more clinically relevant predictors of final alignment than planned MAs. There was decreased variability between the postoperatively-determined MAs compared to preoperatively. There was no difference in the accuracy of obtaining the planned MA postoperatively based on the type of preoperative malalignment (varus/valgus).

Introduction: There are a variety of baseplate options when performing reverse total shoulder arthroplasty (RTSA). Currently, there is no consensus on the optimal glenoid baseplate. The hypothesis of this study was that the use of lateralized baseplates would improve patient-determined outcomes and postoperative range of motion after RTSA compared with standard baseplates without increasing the risk of complications. Methods: Patients undergoing RTSA were stratified into a standard baseplate group (SBG) and a lateralized baseplate group (LBG). The LBG included 3 mm lateralization, 6 mm lateralization, and full-wedge augmentation (8 mm lateralization). The Western Ontario Osteoarthritis Score, American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation (SANE), and Simple Shoulder Test (SST) were recorded at baseline, 1 year, and 2 years. Range of motion was recorded at baseline and 1 year. Differences in complications between groups were recorded. Results: The LBG included 187 patients, and the SBG included 51 patients. No difference was observed in any patient-determined outcome score at 1-year follow-up. At 2 years, there were greater Western Ontario Osteoarthritis Score (84 ± 16 versus 74 ± 19; P = 0.01), American Shoulder and Elbow Surgeons score (81 ± 15 versus 70 ± 20; P = 0.001), SST (8.0 ± 2.4 versus 6.6 ± 2.6; P = 0.007), and SANE (82 ± 17 versus 68 ± 25; P = 0.0005). The improvement in SST (5.0 ± 2.7 versus 3.3 ± 3.6; P = 0.02) and SANE (54 ± 26 versus 37 ± 30; P = 0.004) at 2 years compared with baseline was greater in the LBG compared with the SBG. No difference was observed in any range-of-motion metric between groups. Total complications were similar between groups (P = 0.91). Scapular notching was more prevalent in the SBG (7.8% versus 1.6%; P = 0.01). Conclusion: The LBG had better patient-determined outcome scores compared with the SBG at 2-year follow-up with a similar rate of overall complications but a lower rate of scapular notching. Range of motion was not improved by the use of a lateralized baseplate compared with a standard baseplate.

Background: A prospective cohort study was conducted to assess the predictors of failure of nonoperative treatment, defined as the patient undergoing surgery for symptomatic, atraumatic full-thickness rotator cuff tears. We present the 10-year follow-up data of this population to determine if predictors for surgery change over time, and secondarily we report the outcomes of the cohort. Methods: At the time of enrollment, demographic, symptom, rotator cuff anatomy, and patient-reported outcome data were collected in patients with symptomatic, atraumatic full-thickness rotator cuff tears. Patients underwent a standard physical therapy protocol for 6 to 12 weeks. Patient data were then collected at 1, 2, 5, 7, and 10 years. Failure of nonoperative treatment was defined as the patient electing to undergo surgery. Results: Of the 452 patients in the original cohort, 20 patients (5%) withdrew from the study, 37 (9%) died before 10 years, and 40 (9%) were otherwise lost to follow-up. A total of 115 patients (27.0%) underwent a surgical procedure at some point during the 10-year follow-up period. Of these patients, 56.5% underwent surgery within 6 months of enrollment and 43.5%, between 6 months and 10 years. Low patient expectations regarding the efficacy of physical therapy were found to be a predictor of early surgery. Workers’ Compensation status and activity level were more important predictors of later surgery. Patient-reported outcome measures all improved following physical therapy. For patients who did not undergo a surgical procedure, patient-reported outcome measures did not decline over the 10-year follow-up period. Conclusions: Low patient expectations regarding the efficacy of physical therapy were found to be a predictor of early surgery, whereas Workers’ Compensation status and activity level were predictors of later surgery. Physical therapy was successful in >70% of patients with symptomatic, atraumatic full-thickness rotator cuff tears at 10 years. Outcome measures improved with physical therapy and did not decline over the 10-year follow-up period. Level of Evidence: Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Background: Studies involving human fibroblasts and use of human growth hormone (HGH) administration for injury recovery are limited. It is plausible that if the administration of HGH to human cells increased cellular proliferation and differentiation, then HGH might be able to assist in accelerating recovery from injury. Hypothesis: HGH will increase proliferation and differentiation of human tendon and ligament fibroblasts in vitro based on both a single-dose and a sustained-dose model of HGH administration. Study Design: Basic science cellular study. Methods: Human tendon and ligament tissue were harvested from 24 patients. Tissue samples were digested with type I collagenase to isolate the target cell types. HGH was administered directly to isolated cells at doses ranging from 100 pg/mL to 10 µg/mL, either in a single-dose or a sustained-dose model. Proliferation was analyzed at days 4 and 7. Differentiation of ligament and tendon fibroblasts was assessed at day 14. Results: Administration of a single-dose of HGH to both cell types demonstrated similar or inferior cellular proliferation compared with controls after 7 days. For the sustained-dosing model of ligament fibroblasts, only the 100 ng/mL concentration demonstrated at least statistically similar or improved proliferation compared with controls. When examining the 100 ng/mL HGH concentration with larger sample sizes, cellular proliferation was not improved over controls for any cell type for the single- or sustained-dosing models. Proliferation for tendon fibroblasts was either similar or inferior to the control group at all concentrations of HGH. There was no clear dose-response relationship demonstrating enhanced collagen production with administration of HGH to suggest it enhances injury recovery. Conclusion: HGH administered to human tendon and ligament fibroblasts does not appear to positively affect cellular proliferation and differentiation. Clinical Relevance: This study does not support the use of HGH for accelerating recovery from injury.