Cole, Brian J.

Background: Meniscal preservation has been demonstrated to contribute to long-term knee health and has been a successful intervention in isolation and in patients with anterior cruciate ligament reconstruction (ACLR). The long-term results of meniscal repair in the setting of revision ACLR have yet to be documented. Purpose: To report the incidence of meniscal repair failures at the 6-year follow-up in a cohort of patients who underwent concurrent revision ACLR and primary meniscal repair. Study Design: Prospective cohort study; Level of evidence, 2. Methods: All revision ACLRs with concomitant primary meniscal repair cases from a multicenter group between 2006 and 2011 were selected. Six-year follow-up was obtained to determine whether any subsequent surgery had occurred since their initial revision ACLR. If so, operative reports were obtained, whenever possible, to verify pathological condition and treatment. Results: In total, 221 patients from 1234 revision ACLRs underwent concurrent primary meniscal repairs (18% of the cohort). There were 238 repairs performed: 173 medial and 65 lateral. The majority of these repairs (n = 181; 76%) were performed with an all-inside technique. Six-year surgical follow-up was obtained in 77% (171/221) of the cohort, or 189 of 238 (79%) of the repairs (136 medial, 53 lateral). The meniscal repair failure rate, defined as reoperation, was 16% (31/189) at 6 years. Of the 31 failures, 28 were medial (24 all-inside, 4 inside-out; 28/136 = 20.6% failure rate) and 3 were lateral (2 all-inside, 1 inside-out; 3/53 = 5.7% failure rate). Three medial failures were treated in conjunction with a subsequent repeat revision ACLR. Medial tears underwent reoperation for failure at a significantly higher rate than lateral tears (20.6% vs 5.7%; P = .01) and had a significantly shorter survival time compared with lateral tears ( P = .02). No difference was found between the failure and nonfailure groups when it came to tear type, tear length, repair technique utilized, suture/implant type, or number of sutures used between the 2 groups. Conclusion: Meniscal repair in the revision ACLR setting has a 16% failure rate at 6 years. Failure rates for medial tears (20.6%) were found to be higher than that for lateral tears (5.7%), which aligns with previous studies in both the revision and primary ACLR setting.

Background: Outcomes after arthroscopic rotator cuff repair (RCR) are frequently measured through clinically significant outcomes (CSOs) such as the minimal clinically important difference, the substantial clinical benefit, and the Patient Acceptable Symptom State. Global achievement of CSOs is challenging to predict. Purpose: To determine if unsupervised machine learning can identify distinct patient subgroups based on CSO achievement after elective arthroscopic RCR. Study Design: Case-control study; Level of evidence, 3. Methods: A prospectively collected database was analyzed to identify patients who underwent elective arthroscopic RCR from 2015 to 2017. Tear dimensions were measured on magnetic resonance imaging utilizing a validated technique. CSO achievements on the American Shoulder and Elbow Surgeons, the Single Assessment Numeric Evaluation, and the Constant-Murley subjective score at 2-year follow-up were calculated. An unsupervised random forest algorithm was utilized to develop and internally validate patient subgroups with significantly different rates of CSO achievement. Patient subgroup membership, along with a total of 30 demographic and clinical variables, as well as preoperative patient-reported outcomes, were incorporated into a stepwise multivariable logistic regression to identify factors predictive of optimal CSO achievement. Results: A total of 346 patients (192 male; mean ± SD age, 57.2 ± 9.1 years; body mass index, 30.1 ± 5.4 kg/m 2 ) were eligible for inclusion and followed for a mean of 3.8 years (range, 2.0-6.2 years) Of these, a total of 333 patients were partitioned by the random forest algorithm into 2 subgroups (stability, 0.16; connectivity: 180.8; Dunn: 0.16; silhouette: 0.05), with 176 patients in the optimal achievement subgroup and 157 patients in the suboptimal achievement subgroup. The 2 subgroups differed significantly (all P ≤ .004) in the likelihood of achievement of all CSOs. Stepwise multivariable logistic regression identified an increase of 1 mm in tear size in the sagittal dimension beyond 1.9 cm to predict a 10% increase in the probability of suboptimal achievement. Additional risk factors for suboptimal CSO achievement included increasing number of tendons involved (odds ratio [OR], 14.07; 95% CI, 4.50-44.02; P < .001), subscapularis involvement (OR, 8.67; 95% CI, 2.45-30.71; P = .01), and increased preoperative CMS score (OR, 1.11; 95% CI, 1.04-1.18; P = .001). Protective factors included performance of a subpectoral biceps tenodesis compared with biceps tenotomy (OR, 0.22; 95% CI, 0.05-0.92; P = .03). Conclusion: Clinically meaningful subgroups were uncovered using an unsupervised machine learning algorithm in patients undergoing arthroscopic RCR. Tear size, number of tendons involved, and subscapularis involvement were significant and additive predictors of suboptimal CSO achievement at 2-year minimum follow-up. Treatment of concurrent biceps pathology with tenodesis conferred 78% increased likelihood of CSO achievement compared with tenotomy.

Background: Despite mounting clinical evidence for the utility of orthobiologics in nonoperative management of orthopaedic pathology, the market for orthobiologic therapies remains largely unregulated by the Food and Drug Administration, giving rise to a wide range of pricing for these therapeutics by different provider types. Purpose: To determine the availability and pricing for platelet-rich plasma (PRP), amniotic or adipose “stem cell,” and bone marrow aspirate concentrate (BMC) injections for the treatment of knee osteoarthritis among orthopaedic sports medicine and alternative providers (eg, chiropractic clinics and stand-alone “regenerative medicine” clinics) in a major metropolitan city. Study Design: Cross-sectional study. Methods: Orthopaedic sports medicine providers in the Chicagoland area were identified through the American Orthopaedic Society for Sports Medicine (AOSSM) and Arthroscopy Association of North America (AANA) surgeon databases. Alternative clinics offering orthobiologic injections were systematically compiled using Yelp! and Google search listings and reviews. Clinics were contacted using a standardized telephone script. Data were collected for each site on the types of injections offered, whether price was disclosed over the telephone, the price of injections offered, and the source of stem cell injections if they were provided. Mann-Whitney U tests were used to compare the mean price between practices. F tests for equality of variances were used to compare the variability in prices between practice types. Results: A total of 25 unique orthopaedic sports medicine practices (comprising 80 AOSSM/AANA surgeons) and 40 alternative clinics offered PRP, stem cell, and/or BMC injections, as indicated over the telephone. There was no difference in likelihood of offering PRP ( P = .698) or BMC injections ( P = .340). However, alternative clinics were significantly more likely to offer stem cell injections ( P < .001). There was no difference in the willingness to disclose the price for PRP ( P = .269), stem cell injections ( P = .302), and BMC ( P = .528) or the source of what each clinic advertised as stem cell injections ( P = .630). The mean price for a single PRP injection was significantly higher ( P = .011) and significantly more variable ( F statistic = .139; P < .001) at alternative clinics. Similarly, the mean price for a single stem cell injection was significantly higher ( P < .001) and significantly more variable ( F statistic = 0.080; P = .025) at alternative clinics. Conclusion: This study demonstrates that orthobiologic knee injections are highly prevalent for in-clinic use within the Chicago metropolitan area, with PRP being the most commonly used therapeutic. When compared with orthopaedic sports medicine providers, alternative clinics were more likely to offer stem cell injections and charge a significantly greater and more variable amount per PRP and stem cell treatment.

Purpose To perform a prospective, double‐blind, randomized controlled trial to assess differences in integration and patient‐reported outcomes metrics (PROMs) of osteochondral allograft transplantation with and without bone marrow aspirate concentrate (BMAC) augmentation. Methods Patients (n = 36) undergoing osteochondral allograft transplantation of the knee were consented and enrolled in this prospective study. They were randomized to either iliac crest BMAC or sham incision groups and blinded to their allocation. Computerized tomography (CT) scans of the knee were obtained at 6 months postoperatively after the index transplantation and graded by the semiquantitative assessment CT osteochondral allograft system. PROMs, including the International Knee Documentation Committee and Knee injury and Osteoarthritis Outcome Score–Joint Replacement, were obtained at 6 months, 1 year, and 2 years postoperatively. Results On 6‐month postoperative CT scans, patients receiving BMAC‐treated grafts were more likely to have small cystic changes ( P = .01), with an associated trend toward reduction in large cyst formation ( P = .06), but equal osseous integration, graft signal density, and presence of discernible clefts and intra‐articular fragments. The BMAC group was less likely to undergo subsequent surgery for graft debridement or revision (5.3% vs 35.3%; P = .02). There were no significant differences in PROMs between the 2 groups preoperatively or postoperatively at 6 months, 1 year, or 2 years. Patients receiving BMAC trended toward a higher rate of achievement of Knee Documentation Committee and Knee injury and Osteoarthritis Outcome Score–Joint Replacement minimal clinically important difference (88% vs 55%; P = .076). Conclusions Patients receiving BMAC‐treated grafts were more likely to have small cystic changes and were less likely to undergo subsequent surgery for persistent or new symptoms after the index procedure. No difference in postoperative PROMs was shown at the 6‐month, 1‐year, and 2‐year follow‐ups between the 2 groups. Level of Evidence Level I, prospective, randomized controlled trial.

Purpose To establish consensus statements via a modified Delphi process about ethics, transparency, regulation, and best practices for the use of orthobiologics in clinical practice for musculoskeletal pathology. Methods A consensus process on the regulation of orthobiologics at the provider level was conducted using a modified Delphi technique. Twenty orthopaedic surgeons, sports medicine physicians, or basic scientists participated. Each participant was a Biologic Association member organization representative and asked to participate because of their active interest in the field of orthobiologics. Levels of consensus were delineated according to the number of votes for each statement: no consensus, <80%; consensus, 80% to 89%; strong consensus, 90% to 99%; unanimous, 100%. Results The 26 consensus statements on orthobiologics resulted in 14 achieving unanimous consensus, 8 achieving strong consensus, 3 achieving consensus, and 1 did not achieve consensus. Overall, 85% of the statements reached either a unanimous or strong consensus. Of the statements regarding communication and transparency, 9 reached unanimous consensus, including information to convey and helpful tools to describe current orthobiologics, persistent misinformation, use of the word “stem cells,” “off‐label” use, and problems with the present regulatory environment. Five statements discussing the regulation of novel orthobiologics achieved unanimous consensus. These statements highlighted research regulation, safety, and suggested improvements to regulatory issues. The statement that did not achieve any consensus was on the regulatory processes that should be in place by an institution providing novel orthobiologic treatments. No statement reached a unanimous agreement on cost or ethical considerations. Conclusions This study successfully identified key consensus statements emphasizing the importance of ethics, transparency, and regulation in the use of orthobiologics, with 85% of statements reaching unanimous or strong consensus. These findings underscore the need for standardized communication, improved regulatory frameworks, and enhanced safety measures while highlighting persistent challenges in addressing cost and ethical considerations. Level of Evidence Level V, expert opinion.

Background: Mismatch between osteochondral allograft (OCA) donor and recipient sex has been shown to negatively affect outcomes. This study accounts for additional donor variables and clinically relevant outcomes. Purpose: To evaluate whether donor sex, age, donor-recipient sex mismatch, and duration of graft storage affect clinical outcomes and failure rates after knee OCA transplantation. Study Design: Cohort study; Level of evidence, 3. Methods: Patients undergoing knee OCA transplantation between 2003 and 2018 were prospectively followed. Inclusion criteria consisted of primary OCA transplantation and minimum 2-year follow-up. Patient descriptive data and allograft donor sex, age, and graft storage time before implantation were collected. Patients were evaluated for reoperation, failure, and achievement of clinically significant outcomes for International Knee Documentation Committee scores. Reoperation was defined as subsequent surgical intervention of the transplanted allograft, including second-look arthroscopy for graft evaluation, debridement, and loose body removal. Failure was defined as revision of the primary OCA transplantation or conversion to arthroplasty. A Kaplan-Meier curve determined cumulative survivability of OCA transplantations, and log-rank testing was used to compare survivorship between groups. Stepwise regression analysis was utilized to evaluate associations between donor variables and achievement of clinically significant outcomes, reoperation, and failure. Results: A total of 372 patients undergoing OCA transplantation were included and followed for a mean 5.4 years (SD, 2.7; range, 2.0-16.3). Isolated OCA transplantation was performed in 45% of cases (169/372). A mismatch in donor and recipient sex was present for more female patients (90%) than male patients (10%; P < .001). Those who had a sex-mismatched graft more frequently underwent concomitant tibial tubercle osteotomy ( P = .034). When controlling for patient sex, no other differences were seen between groups matched and mismatched by sex. Univariable and multivariable analysis found no significant difference in survival free from reoperation or failure on the basis of donor-recipient sex mismatch, donor age, or graft storage time before implantation. Conclusion: In contrast to previous historical data, no donor variables were associated with inferior clinical outcomes in patients who underwent OCA transplantation. These data can help inform graft selection, expedient recipient selection, and outcome optimization after OCA transplantation.

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).

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.

Purpose To assess the relation between tendon migration, as measured by radiostereometric analysis, and patient‐reported outcome measures (PROMs) after biceps tenodesis (BT); to determine the likelihood of achieving clinically significant outcomes (CSOs) after BT; and to identify factors that impact CSO achievement. Methods Patients undergoing arthroscopic suprapectoral or open subpectoral BT at a single, high‐volume academic medical center were prospectively enrolled. A tantalum bead sutured to the tenodesis construct was used as a radiopaque marker. Biceps tendon migration was measured on calibrated radiographs at 12 weeks postoperatively. PROMs (Constant‐Murley, Single Assessment Numeric Evaluation [SANE], and Patient‐Reported Outcomes Measurement Information System–Upper Extremity [PROMIS‐UE] scores) were collected preoperatively and at minimum 2‐year follow‐up. Results Of 115 patients enrolled, 94 (82%) were included (median age, 52 years; median body mass index, 31.4). At a mean follow‐up of 2.9 years, the median Constant‐Murley, SANE, and PROMIS‐UE scores were 33 (interquartile range [IQR], 26‐35), 90 (IQR, 80‐99), and 47 (IQR, 42‐58), respectively. Median tantalum bead migration was 6.5 mm (IQR, 1.8‐13.8 mm). There were significant correlations between migration and Constant‐Murley score ( r 2 = 0.222; β = –0.554 [95% confidence interval (CI), –1.027 to –0.081]; P = .022), SANE score ( r 2 = 0.238; β = –0.198 [95% CI, –0.337 to –0.058]; P = .006), and PROMIS‐UE score ( r 2 = 0.233; β = –0.406 [95% CI, –0.707 to –0.104]; P = .009). On univariable analysis, higher body mass index was associated with achievement of substantial clinical benefit (unadjusted odds ratio [OR], 1.078 [95% CI, 1.007 to 1.161]; P = .038). Greater bead migration was negatively associated with achievement of the minimal clinically important difference (unadjusted OR, 0.969 [95% CI, 0.943 to 0.993]; P = .014) and patient acceptable symptomatic state (unadjusted OR, 0.965 [95% CI, 0.937 to 0.989]; P = .008) on all 3 instruments. Conclusions A 1‐cm increase in post‐tenodesis biceps tendon migration was associated with a decrease in the Constant‐Murley, SANE, and PROMIS‐UE scores of 6, 2, and 4 points, respectively, at a mean of 2.9 years after surgery. Most patients achieved CSOs for these PROMs by latest follow‐up, and greater biceps tendon construct migration was negatively associated with the likelihood of CSO achievement. Level of Evidence Level IV, retrospective case series.

Background: Osteochondral allograft (OCA) transplantation is an important surgical technique for full-thickness chondral defects in the knee. For patients undergoing this procedure, topography matching between the donor and recipient sites is essential to limit premature wear of the OCA. Currently, there is no standardized process of donor and recipient graft matching. Purpose: To evaluate a novel topography matching technique for distal femoral condyle OCA transplantation using 3-dimensional (3D) laser scanning to create 3D-printed patient-specific instrumentation in a human cadaveric model. Study Design: Descriptive laboratory study. Methods: Human cadaveric distal femoral condyles (n = 12) underwent 3D laser scanning. An 18-mm circular osteochondral recipient defect was virtually created on the medial femoral condyle (MFC), and the position and orientation of the best topography-matched osteochondral graft from a paired donor lateral femoral condyle (LFC) were determined using an in silico analysis algorithm minimizing articular step-off distances between the edges of the graft and recipient defect. Distances between the entire surface of the OCA graft and the underneath surface of the MFC were evaluated as surface mismatch. Donor (LFC) and recipient (MFC) 3D-printed patient-specific guides were created based on 3D reconstructions of the scanned condyles. Through use of the guides, OCAs were harvested from the LFC and transplanted to the reamed recipient defect site (MFC). The post-OCA recipient condyles were laser scanned. The 360° articular step-off and cartilage topography mismatch were measured. Results: The mean cartilage step-off and graft surface mismatch for the in silico OCA transplant were 0.073 ± 0.029 mm (range, 0.005-0.113 mm) and 0.166 ± 0.039 mm (range, 0.120-0.243 mm), respectively. Comparatively, the cadaveric specimens postimplant had significantly larger step-off differences (0.173 ± 0.085 mm; range, 0.082-0.399 mm; P = .001) but equivalent graft surface topography matching (0.181 ± 0.080 mm; range, 0.087-0.396 mm; P = .678). All 12 OCA transplants had mean circumferential step-off differences less than a clinically significant cutoff of 0.5 mm. Conclusion: These findings suggest that the use of 3D-printed patient-specific guides for OCA transplantation has the ability to reliably optimize cartilage topography matching for LFC to MFC transplantation. This study demonstrated substantially lower step-off values compared with previous orthopaedic literature when also evaluating LFC to MFC transplantation. Using this novel technique in a model performing MFC to MFC transplantation has the potential to yield further enhanced results due to improved radii of curvature matching. Clinical Relevance: Topography-matched graft implantation for focal chondral defects of the knee in patients improves surface matching and has the potential to improve long-term outcomes. Efficient selection of the allograft also allows improved availability of the limited allograft sources.