Faculty Bibliography

BACKGROUND:This study aims to investigate the effect of donor-recipient sex-mismatch on graft survival, patient-reported outcomes (PROs), and return to sport (RTS) following knee osteochondral allograft (OCA) transplantation. METHODS:Patients who underwent knee OCA transplantation between 2011 and 2022 with minimum 2-year clinical follow-up were divided into two cohorts (same-sex (SS) and different-sex (DS) donor). Cumulative survival was compared via multivariable Cox regression analyses controlling for age, graft size, and body mass index (BMI). A sub-analysis comparing PROs between groups was performed, including the Visual Analog Scale (VAS) for pain and satisfaction, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and RTS rates. RESULTS:285 patients were included (189 SS, 96 DS) with mean follow-up of 4.8 ± 2.0 years. There was a graft failure rate of 6.0% with no significant difference in graft survival rate between DS and SS groups (p = 0.70). Sub-analyses between the four donor-recipient groups (male-male, female-male, male-female, and female-female) and between female and male donor groups demonstrated no significant differences in graft survival. Among patients who failed the procedure, time to failure was significantly shorter for those with sex-mismatched grafts (353 days vs. 864 days, p = 0.002). Sub-analysis of a 71-patient cohort with two-year PROs demonstrated no differences between SS and DS groups with respect to satisfaction, pain, or KOOS scores after controlling for sex (p > 0.05). CONCLUSION/CONCLUSIONS:Patients undergoing knee OCA transplantation demonstrated no observable differences in graft survivorship based on donor-recipient graft sex-matching, suggesting that surgeons can use sex-mismatched grafts and expect limited effect on graft survivorship. LEVEL OF EVIDENCE/METHODS:IV.

RATIONALE AND OBJECTIVES/OBJECTIVE:Multiple modalities exist for diagnosing ulnar neuropathy at the elbow (UNE), including electrodiagnostic testing (EDX), ultrasound (US), and magnetic resonance imaging (MRI), with no consensus on the optimal strategy. This study's objective was to determine the most cost-effective diagnostic strategy in patients with suspected UNE. MATERIALS AND METHODS/METHODS:We developed a decision analytic model from the U.S. healthcare perspective over a 1-year time horizon. Our hypothetical population comprised 56-year-old males with medial elbow pain and/or paresthesias radiating to the hand, without weakness. We compared incremental cost-effectiveness and total net monetary benefit (NMB) of single-modality strategies (EDX, US, MRI) and multimodality strategies (combinations of US/MRI, EDX/US, EDX/MRI). Input probabilities and utility values were obtained from the literature, and costs from Centers for Medicaid & Medicare Services and institutional data. The primary outcome was quality-adjusted life years (QALYs). Willingness-to-pay threshold was $100,000. RESULTS:The diagnostic strategy utilizing US first, followed by MRI, was favored with the highest total QALYs, .935, and total NMB, $92,667. EDX and US single-modality strategies were less favorable, with lower total QALYs, .894 and .906, respectively, and lower total NMB, $88,866 and $90,022. Other diagnostic strategies were excluded by absolute or extended dominance. One-way sensitivity analyses found model results sensitive to the utility of UNE recovery, but otherwise robust over a range of costs/probabilities. CONCLUSION/CONCLUSIONS:Our cost-effectiveness analysis suggests an initial US, then MRI is the most cost-effective strategy in the workup of patients with suspected UNE.

PURPOSE/OBJECTIVE:The purpose of this study is to assess the association between sagittal tibial tuberosity-trochlear groove (sTT-TG) distance and patellofemoral chondral lesion size in patients undergoing cartilage restoration procedures. METHODS:A retrospective cohort analysis of patients who underwent an osteochondral allograft transplantation or matrix-induced autologous chondrocyte implantation in the patellofemoral compartment, from 2010 to 2020, were included if they had patellofemoral high-grade lesions, magnetic resonance imaging (MRI) and minimum 2-year follow-up. The preoperative sTT-TG distance was measured independently on axial T2-weighted MRI sequences by two authors, each at least two weeks apart. Intraoperative lesion size was reported according to operative report measurements by the attending surgeon. An interclass correlation coefficient (ICC) was calculated to assess intra- and inter-rater reliability, and categorical data analysis and linear regression models were used to assess the relationship between sTT-TG and lesion size. RESULTS:. Intra- (ICC: 0.99,0.98) and inter-rater reliability (ICC: 0.96) were excellent for both MRI defect size and sTT-TG measurements. The mean sTT-TG was -4.8 ± 4.9 mm and was significantly inversely related to MRI defect size (-0.45, p < 0.01), intraoperative patellar lesion size (-0.32, p = 0.01), total lesion area (-0.22, p = 0.04), but not trochlear lesion size (-0.09, p = 0.56). Multivariable regression demonstrated a more negative sTT-TG remained an independent variable correlated with larger MRI-measured patellofemoral defect sizes and intraoperative patellar lesions. CONCLUSION/CONCLUSIONS:A more negative sTT-TG was an independent variable correlated with larger patellofemoral lesions in patients undergoing patellofemoral cartilage restoration. LEVEL OF EVIDENCE/METHODS:Level III, Diagnostic.

BACKGROUND:Efforts to decrease pain, improve early rehabilitation, and reduce opioid consumption have prompted a focus on peripheral nerve blocks for pain management after anterior cruciate ligament reconstruction (ACLR). The commonly used adductor canal block (ACB) might not provide sufficient postoperative pain control because of its lack of coverage of the posterior aspect of the knee. The addition of the IPACK (interspace between the popliteal artery and the capsule of the posterior knee) block, which targets this area, to the standard ACB could potentially provide better pain control after ACLR over the current standard of care. PURPOSE/HYPOTHESIS/OBJECTIVE:The purpose of this study was to compare and analyze postoperative pain, satisfaction, and opioid demand between the standard ACB and a combination of an ACB and IPACK block in patients undergoing ACLR with a bone-patellar tendon-bone (BTB) autograft. It was hypothesized was that the addition of the IPACK block would substantially improve early postoperative pain control and minimize opioid use. STUDY DESIGN/METHODS:Randomized controlled trial; Level of evidence, 2. METHODS:test or nonparametric test for continuous variables and the chi-square test for categorical variables. Opioid usage was reported as morphine milligram equivalents (MME). RESULTS:< .001). CONCLUSION/CONCLUSIONS:The results of this study suggest that the addition of an IPACK block to an ACB leads to reduced opioid consumption, improved pain control, and higher satisfaction with pain control acutely after ACLR with a BTB autograft. REGISTRATION/BACKGROUND:NCT05286307 (ClinicalTrials.gov).

INTRODUCTION/BACKGROUND:Bone Marrow Lesions (BMLs) have a strong correlation to patient reported pain, functional limitations, joint deterioration, and rapid progression to total knee arthroplasty. The Subchondroplasty® (SCP) Procedure uses AccuFill®, a calcium phosphate bone substitute material (BSM), to treat bone defects such as microtrabecular fractures and BML. METHODS:This observational, prospective, multicenter, cohort study evaluated the effect of the SCP Procedure at two-year follow-up for 70 patients with knee BML. Under arthroscopic and fluoroscopic guidance, the BML was injected with AccuFill®. Patient reported outcomes, including Visual Analog Scale (VAS) pain, Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC), and modified Knee Society Score (mKSS) were collected through 24 months postoperatively. Radiographs and magnetic resonance images (MRI) were performed at baseline and up to 24 months post-operatively. Patient selection was not limited based on degree of osteoarthritis (OA) as determined radiologically by Kellgren-Lawrence (K-L) grade. For a subset of subjects, patient reported outcomes were collected up to five years including pain evaluation, patient knee global assessment, and satisfaction with the procedure. RESULTS:Pre-operative radiographs indicated moderate to severe osteoarthritis (K-L grades 2-4) in 65 subjects (92.8%). Significant improvements (p<0.0001) in mean VAS Pain, IKDC, mKSS and KOOS scores were observed compared with baseline. Kaplan-Meier survivorship free from conversion to knee arthroplasty was 76.2% at two years. The subset of subjects followed for five years demonstrated low pain scores and high procedure satisfaction. CONCLUSION/CONCLUSIONS:This study presents statistically significant and clinically meaningful evidence of improvement in clinical outcomes following SCP for BMLs of the knee after two years. The survivorship rate from arthroplasty at two years was 76.2%. SCP for BMLs can relieve pain with a minimally invasive procedure and may delay the need for knee arthroplasty.

There are multiple etiologies for revision anterior cruciate ligament reconstruction (ACLR), including but not limited to infection, arthrofibrosis, and graft failure, which should be distinguished before revision ACLR. Graft failure occurs when the reconstructed ligament does not restore knee stability, and it includes both graft rupture and functional failure in the setting of an intact graft. The causes of graft failure following ACLR can be divided into surgeon-controllable factors (ie, tunnel position, graft choice, alignment) and patient-centric factors (ie, patient age, tissue quality from systemic disease or smoking, compliance/traumatic reruptures). The purpose of this review is to propose an organized, easy-to-remember algorithm for the workup of surgeon-controlled ACLR graft failure etiologies, represented by the acronym "FATAL Graft."

INTRODUCTION/BACKGROUND:Operative management of multi-ligament knee injuries (MLKI) is technically challenging, with high complication rates. However, the impact of surgeon experience on surgical outcomes remains underreported. This purpose of this study was to examine how surgeon experience impacts operative time and complication rates. It was hypothesized that increased surgeon experience in MLKI correlates with reduced surgical duration and postoperative complications. METHODS:A retrospective review of MLKI patients who underwent reconstruction from 2011 to 2024 by fellowship-trained sports medicine surgeons at two high-volume level 1 trauma centers was conducted. Patient demographics, surgical procedure characteristics, complications, and surgeon experience (defined by years in practice postfellowship) were analyzed. Correlations were examined using linear regression for continuous variables and binary logistic regression for binary variables. RESULTS:There were 191 MLKI patients meeting inclusion criteria, with a 25.7% overall complication rate. Arthrofibrosis (16.2%) was most common, followed by recurrent instability (3.7%), infection (3.7%), revision surgery (2.7%), and hardware removal (1.0%). Controlling for age, sex, BMI, and number of ligaments reconstructed, we found a significant negative correlation between surgeon experience and both surgical duration (ß =  - 0.28, p < .001) and complication risk (OR 0.92, p = 0.024). CONCLUSION/CONCLUSIONS:This study demonstrates that increased surgeon experience in operative management of MLKI is associated with decreased complication rates and shorter procedure duration. Additional risk factors for complications included the number of ligaments injured and concomitant knee dislocation.

PURPOSE/OBJECTIVE:To assess clinical outcomes and return to sport (RTS) rates among patients that undergo osteochondral allograft (OCA) transplantation and autologous chondrocyte implantation (ACI) or matrix-induced autologous chondrocyte implantation (MACI), for patellofemoral articular cartilage defects. METHODS:A retrospective review of patients who underwent an OCA or ACI/MACI from 2010-2020 was conducted. Patient-reported outcomes (PROs) collected included: Visual Analog Scale for pain/satisfaction, Knee Injury and Osteoarthritis Outcome Score (KOOS), and RTS. The percentage of patients that met the Patient Acceptable Symptom State (PASS) for KOOS was recorded. Logistic regression was used to identify predictors of worse outcomes. RESULTS:A total of 95 patients were included (78% follow-up) with ACI or MACI performed in 55 cases (57.9%) and OCA in 40 (42.1%). A tibial tubercle osteotomy was the most common concomitant procedure for OCA (66%) and ACI/MACI (98%). Overall, KOOS pain was significantly poorer in OCA than ACI/MACI (74.7, 95% CI [68.1, 81.1] vs 83.6, 95% CI [81.3, 88.4], p= 0.012), while the remaining KOOS subscores were non-significantly different (all p>0.05). Overall, RTS rate was 54%, with no significant difference in return between OCA or ACI/MACI (52% vs 58%, p= 0.738). There were 26 (27%) reoperations and 5 (5%) graft failures in the entire group. Increasing age was associated with lower satisfaction in OCA and poorer outcomes in ACI/MACI, while larger lesion area was associated with lower satisfaction and poorer outcomes in ACI/MACI. CONCLUSION/CONCLUSIONS:Clinical and functional outcomes were similar in patients that underwent OCA or ACI/MACI for patellofemoral articular cartilage defects at a mean follow-up of 5 years. Patients who received OCA had a higher proportion of degenerative cartilage lesions and, among those with trochlear lesions, reported higher pain at final follow-up than their ACI/MACI counterparts. Overall, increasing age and a larger lesion size were associated with worse patient-reported outcomes.

PURPOSE/OBJECTIVE:To establish consensus statements on the diagnosis, nonoperative management, and labral repair for posterior shoulder instability. METHODS:A consensus process on the treatment of posterior shoulder instability was conducted, with 71 shoulder/sports surgeons from 12 countries participating on the basis of their level of expertise in the field. Experts were assigned to 1 of 6 working groups defined by specific subtopics within posterior shoulder instability. Consensus was defined as achieving 80% to 89% agreement, whereas strong consensus was defined as 90% to 99% agreement, and unanimous consensus was indicated by 100% agreement with a proposed statement. RESULTS:Unanimous agreement was reached on the indications for nonoperative management and labral repair, which include whether patients had primary or recurrent instability, with symptoms/functional limitations, and whether there was other underlying pathology, or patient's preference to avoid or delay surgery. In addition, there was unanimous agreement that recurrence rates can be diminished by attention to detail, appropriate indication and assessment of risk factors, recognition of abnormalities in glenohumeral morphology, careful capsulolabral debridement and reattachment, small anchors with inferior placement and multiple fixation points that create a bumper with the labrum, treatment of concomitant pathologies, and a well-defined rehabilitation protocol with strict postoperative immobilization. CONCLUSIONS:The study group achieved strong or unanimous consensus on 63% of statements related to the diagnosis, nonoperative treatment, and labrum repair for posterior shoulder instability. The statements that achieved unanimous consensus were the relative indications for nonoperative management, and the relative indications for labral repair, as well as the steps to minimize complications for labral repair. There was no consensus on whether an arthrogram is needed when performing advanced imaging, the role of corticosteroids/orthobiologics in nonoperative management, whether a posteroinferior portal is required. LEVEL OF EVIDENCE/METHODS:Level V, expert opinion.

BACKGROUND/UNASSIGNED:Isolated medial compartment knee osteoarthritis (OA) presents a challenging problem to treat for knee surgeons, with a multitude of options from conservative management, including injections and unloader braces, meniscal procedures, osteotomies, and unicompartmental knee arthroplasty (UKA). A new medial implantable shock absorber (MISHA) allows for offloading 142 N of the medial compartment during stance phase of gait. INDICATIONS/UNASSIGNED:US Food and Drug Administration approval was obtained on April 10, 2023, with the following indications: isolated medial knee OA (Kellgren-Lawrence grades I-IV) that failed 6 months of conservative management, ages 25 to 65 years, body mass index <35 or body weight <300 lbs, <15° of varus, no flexion contracture >10°, and no significant medial osteophytes or medial meniscal extrusion. TECHNIQUE DESCRIPTION/UNASSIGNED:A longitudinal medial knee incision is made 1 cm proximal to the medial epicondyle to the pes insertion, around 3 cm medial to the tibial tubercle, exposing the superficial medial collateral ligament, and medial joint line. The establishment of the femoral anisometric point is critical to provide a 4-mm posterior condylar offset in 90° of flexion compared to full extension. A trial implant can be placed to confirm appropriate anisometry, implant loading in extension, and relaxation in flexion. The final implant is placed and the titanium femoral and tibial baseplates are fixed with 3 unicortical titanium locking screws each. RESULTS/UNASSIGNED:Expected results per recommended postoperative protocol are immediate weightbearing without range of motion restrictions. From author experience, patients typically feel improvement and return to sport more rapidly than with anterior cruciate ligament reconstructions. Recovery and return to work are faster than osteotomies or UKAs based on comparative short-term studies. While long-term results are lacking given the novelty of the procedure, prospective studies have demonstrated 100% arthroplasty-free survival at 2 years and 85% survival at 5 years. DISCUSSION/CONCLUSION/UNASSIGNED:The MISHA is a viable option for isolated medial compartment knee OA that provides a joint-preserving alternative to arthroplasty and a less morbid alternative to osteotomy. This treatment can be technically difficult to perform, but several pearls and techniques can offer a reproducible, minimally invasive surgery and good functional results. PATIENT CONSENT DISCLOSURE STATEMENT/UNASSIGNED:The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.