Journal of Shoulder and Elbow Surgery最新文献

Background: Augmented baseplates can be effective at addressing eccentric glenoid wear in reverse total shoulder arthroplasty. However, these implants often come in a limited number of predetermined shapes that require additional reaming to ensure adequate glenoid seating. This typically involves complex instrumentation and can have a negative impact on implant stability. Modular baseplate augmentation based on intraoperative measurements may allow for more precise defect filling while preserving glenoid bone. The purpose of this investigation was to assess the stability of a novel ringed baseplate with modular augmentation in comparison with nonaugmented standard and ringed baseplate designs.

Methods: In this biomechanical study, baseplate micromotion was tested for 3 constructs according to the American Society for Testing and Materials guidelines. The constructs included a nonaugmented curved baseplate, a nonaugmented ringed baseplate, and a ringed baseplate with an 8-mm locking modular augmentation peg. The nonaugmented constructs were mounted flush onto polyurethane foam blocks, whereas the augmented baseplate was mounted on a polyurethane block with a simulated defect. Baseplate displacement was measured before and after 100,000 cycles of cyclic loading.

Results: Before cyclic loading, the nonaugmented and augmented ringed baseplates both demonstrated significantly less micromotion than the nonaugmented curved baseplate design (81.1 μm vs. 97.2 μm vs. 152.7 μm; P = .009). After cyclic loading, both ringed constructs continued to have significantly less micromotion than the curved design (105.5 μm vs. 103.2 μm vs. 136.6 μm; P < .001). The micromotion for both ringed constructs remained below the minimum threshold required for bony ingrowth (150 μm) at all time points.

Conclusions: In the setting of a simulated glenoid defect, locked modular augmentation of a ringed baseplate does not result in increased baseplate micromotion when compared with full contact nonaugmented baseplates. This design offers a simple method for tailored baseplate augmentation that can match specific variations in glenoid anatomy, limiting the need for excessive reaming and ultimately optimizing the environment for long-term implant stability.

Background: Although Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity (P-UE) has been validated in upper extremity orthopedics, its ability to capture a patient's functional recovery after arthroscopic rotator cuff repair (aRCR), as measured by its responsiveness, is minimal in the early postoperative period. The primary purpose of this study is to determine if the addition of PROMIS Pain Intensity (P-Intensity) or Pain Interference (P-Interference) scores to PROMIS UE improves the responsiveness throughout the 1-year postoperative period after aRCR.

Methods: This prospective, longitudinal study included 100 patients who underwent aRCR. Patients completed P-UE, P-Interference, P-Intensity, American Shoulder and Elbow Surgeons, and Western Ontario Rotator Cuff Index scores preoperatively and at 2 weeks, 6 weeks, 3 months, 6 months, and 12 months after surgery. Responsiveness at each time point relative to preoperative baseline and 1-way analysis of variance with post hoc analysis was conducted for each PROM. The responsiveness of the outcome score was determined using the effect size, graded as small (0.2), medium (0.5), or large (0.8). The Pearson correlation coefficient (r) was determined between these instruments at each time point.

Results: In isolation, P-UE, P-Interference, and P-Intensity showed a medium-large ability to detect change (positive and negative) throughout the 1-year postoperative period. The addition of PROMIS pain scores to P-UE improved the responsiveness of the instrument (from medium to a large effect size) starting at 3 months and continued throughout the 12-month follow-up period. Although the addition of pain scores increases the response burden for PROMIS, this was still lower than the response burden for the legacy outcome scores (P < .05).

Conclusion: The addition of PROMIS pain instruments improves the responsiveness of the P-UE function score in patients undergoing aRCR.

Background: Navigated augmented reality (AR) through a head-mounted display (HMD) has led to accurate glenoid component placement in reverse shoulder arthroplasty (RSA) in an in-vitro setting. The purpose of this study is to evaluate the deviation between planned, intraoperative, and postoperative inclination, retroversion, entry point, and depth of the glenoid component placement during RSA, assisted by navigated AR through an HMD, in a surgical setting.

Methods: A prospective, multicenter study was conducted. All consecutive patients undergoing RSA in 2 institutions, between August 2021 and January 2023, were considered potentially eligible for inclusion in the study. Inclusion criteria were as follows: age >18 years, surgery assisted by AR through an HMD, and postoperative computed tomography (CT) scans at 6 weeks. All participants agreed to participate in the study and informed consent was provided in all cases. Preoperative CT scans were undertaken for all cases and used for 3-dimensional (3D) planning. Intraoperatively, glenoid preparation and component placement were assisted by a navigated AR system through an HMD in all patients. Intraoperative parameters were recorded by the system. A postoperative CT scan was undertaken at 6 weeks, and 3D reconstruction was performed to obtain postoperative parameters. The deviation between planned, intraoperative, and postoperative inclination, retroversion, entry point, and depth of the glenoid component placement was calculated. Outliers were defined as >5° for inclination and retroversion and >5 mm for entry point.

Results: Seventeen patients (9 females, 12 right shoulders) with a mean age of 72.8 ± 9.1 years (range, 47.0-82.0) met inclusion criteria. The mean deviation between intra- and postoperative measurements was 1.5° ± 1.0° (range, 0.0°-3.0°) for inclination, 2.8° ± 1.5° (range, 1.0°-4.5°) for retroversion, 1.8 ± 1.0 mm (range, 0.7-3.0 mm) for entry point, and 1.9 ± 1.9 mm (range, 0.0-4.5 mm) for depth. The mean deviation between planned and postoperative values was 2.5° ± 3.2° (range, 0.0°-11.0°) for inclination, 3.4° ± 4.6° (range, 0.0°-18.0°) for retroversion, 2.0 ± 2.5 mm (range, 0.0°-9.7°) for entry point, and 1.3 ± 1.6 mm (range, 1.3-4.5 mm) for depth. There were no outliers between intra- and postoperative values and there were 3 outliers between planned and postoperative values. The mean time (minutes : seconds) for the tracker unit placement and the scapula registration was 03:02 (range, 01:48 to 04:26) and 08:16 (range, 02:09 to 17:58), respectively.

Conclusion: The use of a navigated AR system through an HMD in RSA led to low deviations between planned, intraoperative, and postoperative parameters for glenoid component placement.

Background: Baseball is one of the most popular sports among youth athletes in the United States, and among these players, pitchers are at a particularly high risk of sustaining an injury. Overuse of the arm from repetitive pitching is a common mechanism for injury. Despite the attention that overuse injury has received, little is known regarding the mechanism that leads to elbow injury. This study aims to determine the effect of increasing pitch count on elbow flexion at ball release in a youth pitching cohort. The authors hypothesize that elbow flexion would increase as pitch count increases.

Methods: Study subjects included volunteers from youth baseball players from local teams and public advertisements. Retroreflective markers attached to bony landmarks were placed on the players according to International Shoulder Group recommendations. Pitchers threw an indoor simulated game. Three-dimensional marker trajectories were collected using a 12-camera optical motion capture system, and ball velocity was captured using a radar gun. Voluntary maximal isometric strength of the internal and external rotators was evaluated before and after pitching. Paired 2-tailed t tests were performed to determine if a significant change occurred between the fresh and fatigued sets.

Results: Twelve adolescent male pitchers were recruited. Eleven of 12 pitchers completed the prescribed 6 sets of 15 pitches, culminating in a 90-pitch simulated game. The ball speed in the second set was found to be the highest in all pitchers and was considered the "peak set" (P = .021), whereas ball speed was the slowest in the sixth set of pitches and was therefore considered the "fatigue set" (P = .001). There was a moderate but statistically significant inverse correlation between elbow flexion at ball release and maximum internal rotation velocity (P = .005). Elbow flexion at ball release was also significantly positively correlated with shoulder abduction at ball release (P = .004). Elbow flexion at ball release was not significantly correlated with ball velocity (P = .108).

Conclusions: In a simulated game laboratory setting, increasing pitch count was associated with increasing elbow flexion angle at ball release in youth baseball pitchers. These findings demonstrate that pitching with fatigue may cause biomechanical changes that have been associated with increased rates of elbow injury in the adult throwing population. Further investigation on the association between elbow flexion angle and elbow injury in the youth baseball population is needed.

Background: The primary objective of this study was to evaluate and compare the incidence of complications and revision surgeries between in 2 of convertible metal-back glenoid systems in total shoulder arthroplasty (aTSA) groups over a follow-up period of up to 5 years.

Methods: A retrospective analysis included 69 shoulders from 65 patients with primary aTSA. Patients were divided into group 1 (n = 31), receiving convertible cementless stemmed aTSA (Lima SMR) and group 2 (n = 38), receiving humeral head replacement aTSA (Arthrex, Eclipse) both with metal-back glenoid components. Clinical and radiological assessments were conducted at 2, 5, and 10 years postoperatively. Assessments included the following: Constant Score, Disabilities of the Arm, Shoulder, and Hand, Shoulder Pain and Disability Index, Subjective Shoulder Value, Glenohumeral Distance, Critical Shoulder Angle, and Lateral Acromion Index. In addition, we compared complications, revision rates, and survival rates between groups using Kaplan-Maier curves and Log-Rank-test.

Results: Baseline demographics and preoperative outcome scores showed no significant differences between groups (P ≥ .05). The overall revision rate did not significantly differ between groups (group 1:32% vs. group 2:24%, P = .60), nor did the mean time to revision (P = .27). The mean follow-up was 71 ± 41 months (group 1: 94 ± 48 months, group 2: 53 ± 23 months, P < .001). Kaplan-Meier analysis showed similar midterm survival probabilities (P = .94). Revision reasons included rotator cuff insufficiency (n = 4 in group 1, n = 2 in group 2) and glenoid wear/loosening (n = 5 in group 1, n = 7 in group 2). Interestingly, group 1 demonstrated no occurrence of glenoid metal baseplate or humeral loosening, while complex revisions were more common in the group 2. At 2 and 5 years, nonrevised patients in both groups had similar outcome scores.

Conclusion: Metal-backed glenoid implants in combination with both stemless and stemmed humeral components in aTSA exhibit comparable revision rates and survival probabilities. Rotator cuff insufficiency and polyethylene wear are the 2 most common complications leading to revision. To facilitate ongoing monitoring and optimize patient safety, we implemented a modification in the follow-up protocol, transitioning to annual appointments or earlier when necessary. This study underscores the unsolved disadvantages in metal-back components and the importance of a midterm to long-term longitudinal assessment of those patients.

Background: Reverse total shoulder arthroplasty (RTSA) is the standard of care for patients with glenohumeral osteoarthritis and rotator cuff deficiency. Preoperative RTSA planning based on medical images and patient-specific instruments has been established over the last decade. This study aims to determine the effects of using augmented reality-assisted intraoperative navigation (ARIN) for baseplate positioning in RTSA compared to preoperative planning. It is hypothesized that ARIN will decrease deviation between preoperative planning and postoperative baseplate positioning. Moreover, ARIN will decrease deviation between the (senior) more (>50 RTSAs/yr) and less experienced (junior) surgeon (5-10 RTSAs/yr).

Methods: Preoperative CT scans of 16 fresh-frozen cadaveric shoulders were obtained. Baseplate placements were planned using a validated software. The data were then converted and uploaded to the augmented reality system (NextAR; Medacta International). Each of the 8 RTSAs were implanted by a senior and a junior surgeon, with 4 RTSAs using ARIN and 4 without. A postoperative CT scan was performed in all cases. The scanned scapulae were segmented, and the preoperative scan was laid over the postoperative scapula by the nearest iterative point cloud analysis. The deviation from the planned entry point and trajectory was calculated regarding the inclination, retroversion, medialization (reaming depth) and lateralization, anteroposterior position, and superoinferior position of the baseplate. Data are reported as mean ± standard deviation (SD) or mean and 95% confidence interval (CI). P values < .05 were considered statistically significant.

Results: The use of ARIN yielded a reduction in the absolute difference between planned and obtained inclination from 9° (SD: 4°) to 3° (SD: 2°) (P = .011). Mean difference in planned-obtained inclination between surgeons was 3° in free-hand surgeries (95% CI: -4 to 10; P = .578), whereas this difference reduced to 1° (95% CI: -6 to 7, P = .996) using ARIN. Retroversion, medialization (reaming depth) and lateralization, anteroposterior position, and superoinferior position of the baseplate were not affected by using ARIN. Surgical duration was increased using ARIN for both the senior (10 minutes) and junior (18 minutes) surgeon.

Conclusions: The implementation of ARIN leads to greater accuracy of glenoid component placement, specifically with respect to inclination. Further studies have to verify if this increased accuracy is clinically important. Furthermore, ARIN allows less experienced surgeons to achieve a similar level of accuracy in component placement comparable to more experienced surgeons. However, the potential advantages of ARIN in RTSA are counterbalanced by an increase in operative time.

Background: Stemless implants were introduced to prevent some of the stem-related complications associated with the total shoulder arthroplasty. Although general requirements for receiving these implants include good bone quality conditions, little knowledge exists about how bone quality affects implant performance. The goal of this study was to evaluate the influence of age-induced changes in bone density, as a metric of bone quality, in the primary stability of five anatomic stemless shoulder implants using three-dimensional finite element (FE) models.

Methods: The implant designs considered were based on the Global Icon, Sidus, Simpliciti, SMR, and Inhance stemless implants. Shoulder arthroplasties were virtually simulated in Solidworks. The density distributions of 20 subjects from two age groups, 20-40 and 60-80 years old, were retrieved from medical image data and integrated into three-dimensional FE models of a single humerus geometry, developed in Abaqus, to avoid confounding factors associated with geometric characteristics. For the designs which do not have a solid collar covering the entire bone surface, ie, the Sidus, Simpliciti, SMR, and Inhance implants, contact and noncontact conditions between the humeral head component and bone were considered. Primary stability was evaluated through the assessment of micromotions at the bone-implant interface considering eight load cases related to rehabilitation activities and demanding tasks. Three research variables, considering 20 μm, 50 μm, and 150 μm as thresholds for osseointegration, were used for a statistical analysis of the results.

Results: The decreased bone density registered for the 60-80 age group led to larger micromotions at the bone-implant interface when compared to the 20-40 age group. The Global Icon-based and Inhance-based designs were the least sensitive to bone density, whereas the Sidus-based design was the most sensitive to bone density. The establishment of contact between the humeral head component and bone for the implants that do not have a solid collar led to decreased micromotions.

Discussion: Although the age-induced decline in bone density led to increased micromotions in the FE models, some stemless shoulder implants presented good overall performance regardless of the osseointegration threshold considered, suggesting that age alone may not be a contraindication to anatomic total shoulder arthroplasty. If only primary stability is considered, the results suggested superior performance for the Global Icon-based and Inhance-based designs. Moreover, the humeral head component should contact the resected bone surface when feasible. Further investigation is necessary to combine these results with the long-term performance of the implants and allow more precise recommendations.

Background: Recovery after anatomic total shoulder arthroplasty (aTSA) and reverse total shoulder arthroplasty (rTSA) has many similarities; however, recently surgeons have suggested patients undergoing rTSA have a less difficult postoperative course with less pain compared with aTSA patients. Given the heightened awareness to postoperative pain control and opioid consumption, as well as the expanding indications for rTSA, we sought to determine the differences in pain and opioid consumption between aTSA and rTSA patients in a 12-week postoperative period.

Methods: A retrospective chart review was performed to identify all patients who underwent a primary aTSA or rTSA from January 2013 to April 2018 at a single institution. Patients with recorded visual analog scale (VAS) and American Shoulder and Elbow Surgeons scores were included for analysis. Revision arthroplasties were excluded. VAS scores were recorded preoperatively and at standard 2-week, 6-week, and 12-week postoperative time points. P values < .05 were considered statistically significant, except where Bonferroni corrections were applied.

Results: A total of 690 patients underwent TSA (278 aTSA, 412 rTSA). Preoperatively, aTSA and rTSA patient groups had similar VAS scores (6 vs. 6, P = .38). Postoperatively, the aTSA group had a higher VAS at the 6-week visit, compared with rTSA patients (2.8 vs. 2.2, P = .003). aTSA patients remained on opioids at a higher rate at the 2-week (62.4% vs. 45.6%, P ≤ .001) time period. aTSA patients needed more opioid prescription refills before the 2-week (61.7% vs. 45.5%, P ≤ .001) and 6-week (40.4% vs. 30.7%, P = .01) follow-up visits.

Conclusions: Despite similar preoperative VAS and rates of preoperative opioid use, aTSA patients required more opioid medication refills and remained on opioids for a longer duration in the early postoperative period to achieve similar postoperative pain control as indicated by similar VAS. This study suggests that the recovery from rTSA is less difficult compared with aTSA as indicated by VAS and opioid consumption.