Publications by Year: 2024

BACKGROUND: Stemless shoulder arthroplasty offers several advantages, such as preserving bone stock and reducing periprosthetic fracture risk. However, implant motion can deter osteointegration and increase bone resorption, where micromotion less than 0.150 mm is crucial for bony ingrowth and vital to the success of the implant. The interaction between the implant and the metaphyseal bone and its effects on stability remains unclear. Therefore, this cadaveric study aims to assess the immediate stability of two stemless prostheses in low bone density specimens.

METHODS: Twenty cadaveric shoulders were used to compare the stability of two stemless shoulder implants by Zimmer-Biomet (model A) and Exactech (model B), subjected to loads of 220 N, 520 N, and 820 N to assess strain and micromotion.

FINDINGS: Micromotion at 220 N load was 0.061 ± 0.080 mm and 0.053 ± 0.050 mm, and at 520 N load, 0.279 ± 0.37 mm and 0.311 ± 0.35 mm for models A and B, respectively. The estimated mean force required to achieve a 150 μm micromotion was 356 ± 116 N and 315 ± 61 N for models A and B, respectively. Motion analysis revealed distinct movement patterns for each implant, with model B demonstrating better force distribution on the bone despite no significance.

INTERPRETATION: Forces over 520 N (high postoperative rehabilitation force) could hinder bone integration with prostheses due to excessive micromotion. Conversely, forces around 220 N (preconditioning loading force) are considered safe for prosthesis stability even with low bone density. These insights may caution against using stemless implants when bone density is low, and help guide clinical decisions on the duration of rehabilitation and sling use after stemless arthroplasty.

BACKGROUND: Augmentation of an arthroscopic Bankart repair with the remplissage (ABR) procedure has shown to confer a decrease in recurrence rates, yet, at the expense of potentially compromising shoulder motion.

PURPOSE/HYPOTHESIS: The purpose was to examine clinical studies that described a post-operative rehabilitation protocol after an arthroscopic Bankart repair and remplissage procedure. It was hypothesized that a review of the literature would find variability among the studies and that, among comparative studies, there would be a limited distinction from protocols for isolated Bankart repairs.

STUDY DESIGN: Systematic Review.

MATERIALS AND METHODS: A search was conducted using three databases (PubMed, EMBASE, and CINAHL) according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. The following terms were combined while utilizing Boolean operators: (Bankart lesion OR labral tear) AND (remplissage). Studies evaluating patients after arthroscopic stabilization for unidirectional anterior glenohumeral instability with the addition of the remplissage procedure and at least 1 year follow-up were included for analysis.

RESULTS: A total of 41 studies (14 Level IV, 24 Level III, 2 Level II, and 1 Level I) were included with a total of 1,307 patients who underwent ABR. All patients had <30% glenoid bone loss and a range of 10-50% humeral head size Hill-Sachs lesion. Type and position of immobilization were the most reported outcomes (41/41) followed by time of immobilization (40/41). Moreover, 23/41 studies described their initial post-operative shoulder range of motion restrictions, while 17/41 specified any shoulder motion allowed during this restrictive phase. Time to return to sport was also described in 37/41 of the retrieved studies. Finally, only two of the 27 comparative studies tailored their rehabilitation protocol according to the specific procedure performed, underscoring the lack of an individualized approach (i.e. same rehabilitation protocol for different procedures).

CONCLUSION: The results of the present systematic review expose the variability among rehabilitation protocols following ABR. This variability prompts consideration of the underlying factors influencing these disparities and underscores the need for future research to elucidate optimal rehabilitation. Based on the results of this systematic review and the senior authors´ clinical experience, a rehabilitation approach similar to an isolated Bankart repair appears warranted, with additional precautions being utilized regarding internal rotation range of motion and external rotation strengthening.

LEVEL OF EVIDENCE: Level 3.

Background: Free tissue transfer is a valuable surgical option for the reconstruction of a myriad of complex lower extremity defects. Currently, there is a paucity of data that examines the risks of complications for each of these unique indications. Methods: Patients undergoing lower extremity free flap reconstruction from the ACS-NSQIP 2011-2019 database were stratified into groups based on the etiology and indication for reconstruction. Rates of major, surgical wound, and medical complications were compared over the first post-operative month. Multivariable logistic regression was used to identify complication predictors. Results: 425 lower extremity free flaps were analyzed. The most common indications for lower extremity free flap reconstruction were wound-related (29%), malignancy (21%), and trauma (17%). Seventeen percent of free flaps had a major post-operative complication, 9% had a surgical wound complication, and 16% had a medical complication. There were no significant differences in major complications between the indications. However, the independent risk factors for major complications varied widely. Those with an indication of malignancy and those who received a musculocutaneous free flap were significantly more likely to have a surgical wound complication compared to the remaining cohort (p < 0.05). Those requiring free flap reconstruction for orthopedic hardware related concerns as well as those with wound related indications were significantly more likely to have a post-operative medical complication (p < 0.05). Conclusion: Understanding the unique risk profiles between the various indications and populations of patients undergoing lower extremity free flap reconstruction is critical for providing accurate risk estimations and optimizing post-operative outcomes and monitoring. Keywords microsurgery, lower extremity free flap, free flap reconstruction.

BACKGROUND: While rotator cuff tears are prevalent in the general population, the natural history of this disease is unclear. Understanding rotator cuff tear progression is crucial for refining surgical indications and evaluating the necessity of early interventions. This study presents an in-depth analysis of the existing literature on the definitions and progression rates of rotator cuff tears, aiming to enhance clinical decision making and patient outcomes.

METHODS: A systematic literature search was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using Medline (PubMed), Embase (Elsevier), and Web of Science databases on January 12, 2023. Articles were identified as relevant to the natural history and progression of asymptomatic and symptomatic partial-thickness (PT) and full-thickness (FT) rotator cuff tears. Those written in English reporting rotator cuff progression rates of tears in adults, based on magnetic resonance imaging (MRI) or ultrasound, were included. After reviewing the articles, the data on the rates of tear progression and associated risk factors were extracted, compiled, and analyzed. The risk of bias was determined using the Newcastle-Ottawa Scale.

RESULTS: Twenty-one articles met the inclusion criteria, with 1,831 tears included. The progression rate for all partial thickness tears was 26.7% ± 12.8% at an average follow-up of 2.2 ± 0.9 years, with 5 definitions for tear progression. For FT tears, the progression rate was 54.9% ± 18.6% at a follow-up time of 3.0 ± 2.0 years, with 8 definitions for tear enlargement. A significant difference (p < 0.0001) was found between the progression rates of PT and FT tears. Patients who were initially asymptomatic and became symptomatic had higher progression rates (33%-63%) than those who remained asymptomatic (4%-38%).

CONCLUSION: Further research would benefit by identifying a clinically relevant and standardized definition of rotator cuff tear progression, to describe the natural history of rotator cuff disease, making results more comparable and optimizing treatment planning.

LEVEL OF EVIDENCE: Level II. See Instructions for Authors for a complete description of levels of evidence.

Socioeconomic factors have been associated with an increased need for manipulation under anesthesia (MUA) following total knee arthroplasty (TKA). The purpose of this study was to compare the rate of MUA and range of motion (ROM) following primary TKA in English and non-English-speaking patients. The authors conducted a retrospective cohort study of all primary TKAs performed at their institution between 2010 and 2017. A total of 1,099 English-speaking and 163 non-English-speaking patients were included. There was no significant difference in rate of MUA (3.5 vs. 4.9%, p = 0.392) or postoperative ROM (102.2 vs. 100°, p = 0.142) between English and non-English-speaking patients. Younger age (p = 0.001) and female sex (p = 0.005), but not patient language, were associated with need for MUA. Patient language does not appear to impact the rate of MUA or ROM following TKA. (Journal of Surgical Orthopaedic Advances 33(3):158-161, 2024).

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Accurately diagnose scaphoid fractures through examination and appropriate imaging selection. 2. Recognize those fractures that can be treated with nonoperative management. 3. Outline the different surgical approaches for scaphoid fractures. 4. Appreciate the surgical options for management of scaphoid nonunion.

SUMMARY: This article includes the most up-to-date information on the diagnosis, work-up, and treatment of scaphoid fractures.

Partial-thickness rotator cuff tears are a common cause of pain and disability and are central to developing full-thickness rotator cuff tears. However, limited knowledge exists regarding the alterations to the mechanical environment due to these lesions. Computational models that study the alterations to the mechanical environment of the supraspinatus tendon can help advance clinical management to avoid tear progression and provide a basis for surgical intervention. In this study, we use three-dimensional validated finite element models from six intact specimens to study the effects of low- and high-grade tears originating on the articular and bursal surfaces of the supraspinatus tendon. Bursal-sided tears generally had a lower failure load, modulus, and strain than articular-sided tears. Thus, caution should be taken when managing bursal-sided tears as they may be more susceptible to tear progression.

BACKGROUND: Revision anterior cruciate ligament (ACL) reconstruction has been documented to have inferior outcomes compared with primary ACL reconstruction. The reasons why remain unknown.

PURPOSE: To determine whether surgical factors performed at the time of revision ACL reconstruction can influence a patient's outcome at 6-year follow-up.

STUDY DESIGN: Cohort study; Level of evidence, 2.

METHODS: Patients who underwent revision ACL reconstruction were identified and prospectively enrolled between 2006 and 2011. Data collected included baseline patient characteristics, surgical technique and pathology, and a series of validated patient-reported outcome instruments: Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) subjective form, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx activity rating score. Patients were followed up for 6 years and asked to complete the identical set of outcome instruments. Regression analysis was used to control for baseline patient characteristics and surgical variables to assess the surgical risk factors for clinical outcomes 6 years after surgery.

RESULTS: A total of 1234 patients were enrolled (716 men, 58%; median age, 26 years), and 6-year follow-up was obtained on 79% of patients (980/1234). Using an interference screw for femoral fixation compared with a cross-pin resulted in significantly better outcomes in 6-year IKDC scores (odds ratio [OR], 2.2; 95% CI, 1.2-3.9; P = .008) and KOOS sports/recreation and quality of life subscale scores (OR range, 2.2-2.7; 95% CI, 1.2-4.8; P < .01). Use of an interference screw compared with a cross-pin resulted in a 2.6 times less likely chance of having a subsequent surgery within 6 years. Use of an interference screw for tibial fixation compared with any combination of tibial fixation techniques resulted in significantly improved scores for IKDC (OR, 1.96; 95% CI, 1.3-2.9; P = .001); KOOS pain, activities of daily living, and sports/recreation subscales (OR range, 1.5-1.6; 95% CI, 1.0-2.4; P < .05); and WOMAC pain and activities of daily living subscales (OR range, 1.5-1.8; 95% CI, 1.0-2.7; P < .05). Use of a transtibial surgical approach compared with an anteromedial portal approach resulted in significantly improved KOOS pain and quality of life subscale scores at 6 years (OR, 1.5; 95% CI, 1.02-2.2; P≤ .04).

CONCLUSION: There are surgical variables at the time of ACL revision that can modify clinical outcomes at 6 years. Opting for a transtibial surgical approach and choosing an interference screw for femoral and tibial fixation improved patients' odds of having a significantly better 6-year clinical outcome in this cohort.

AIMS: Lower limb fractures are common in low- and middle-income countries (LMICs) and represent a significant burden to the existing orthopaedic surgical infrastructure. In high income country (HIC) settings, internal fixation is the standard of care due to its superior outcomes. In LMICs, external fixation is often the surgical treatment of choice due to limited supplies, cost considerations, and its perceived lower complication rate. The aim of this systematic review protocol is identifying differences in rates of infection, nonunion, and malunion of extra-articular femoral and tibial shaft fractures in LMICs treated with either internal or external fixation.

METHODS: This systematic review protocol describes a broad search of multiple databases to identify eligible papers. Studies must be published after 2000, include at least five patients, patients must be aged > 16 years or treated as skeletally mature, and the paper must describe a fracture of interest and at least one of our primary outcomes of interest. We did not place restrictions on language or journal. All abstracts and full texts will be screened and extracted by two independent reviewers. Risk of bias and quality of evidence will be analyzed using standardized appraisal tools. A random-effects meta-analysis followed by a subgroup analysis will be performed, given the anticipated heterogeneity among studies, if sufficient data are available.

CONCLUSION: The lack of easily accessible LMIC outcome data, combined with international clinical guidelines that are often developed by HIC surgeons for use in HIC environments, makes the clinical decision-making process infinitely more difficult for surgeons in LMICs. This protocol will guide research on surgical management, outcomes, and complications of lower limb shaft fractures in LMICs, and can help guide policy development for better surgical intervention delivery and improve global surgical care.

BACKGROUND: As machine learning becomes increasingly utilized in orthopaedic clinical research, the application of machine learning methodology to cohort data from the Multicenter ACL Revision Study (MARS) presents a valuable opportunity to translate data into patient-specific insights.

PURPOSE: To apply novel machine learning methodology to MARS cohort data to determine a predictive model of revision anterior cruciate ligament reconstruction (rACLR) graft failure and features most predictive of failure.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: The authors prospectively recruited patients undergoing rACLR from the MARS cohort and obtained preoperative radiographs, surgeon-reported intraoperative findings, and 2- and 6-year follow-up data on patient-reported outcomes, additional surgeries, and graft failure. Machine learning models including logistic regression (LR), XGBoost, gradient boosting (GB), random forest (RF), and a validated ensemble algorithm (AutoPrognosis) were built to predict graft failure by 6 years postoperatively. Validated performance metrics and feature importance measures were used to evaluate model performance.

RESULTS: The cohort included 960 patients who completed 6-year follow-up, with 5.7% (n = 55) experiencing graft failure. AutoPrognosis demonstrated the highest discriminative power (model area under the receiver operating characteristic curve: AutoPrognosis, 0.703; RF, 0.618; GB, 0.660; XGBoost, 0.680; LR, 0.592), with well-calibrated scores (model Brier score: AutoPrognosis, 0.053; RF, 0.054; GB, 0.057; XGBoost, 0.058; LR, 0.111). The most important features for AutoPrognosis model performance were prior compromised femoral and tibial tunnels (placement and size) and allograft graft type used in current rACLR.

CONCLUSION: The present study demonstrated the ability of the novel AutoPrognosis machine learning model to best predict the risk of graft failure in patients undergoing rACLR at 6 years postoperatively with moderate predictive ability. Femoral and tibial tunnel size and position in prior ACLR and allograft use in current rACLR were all risk factors for rACLR failure in the context of the AutoPrognosis model. This study describes a unique model that can be externally validated with larger data sets and contribute toward the creation of a robust rACLR bedside risk calculator in future studies.

REGISTRATION: NCT00625885 (ClinicalTrials.gov identifier).