Citations

Abstract Platelet‐rich plasma (PRP) continues to generate both excitement and skepticism within orthopaedics and sports medicine. As a biologic derived from autologous blood, PRP offers an appealing, minimally invasive option for treating musculoskeletal pathology through the delivery of concentrated growth factors and cytokines. Evidence across orthopaedic subspecialties remains mixed, however, with studies showing variable efficacy and inconsistent methodologies. Recent data on PRP use for extra‐articular hip pathology, particularly greater trochanteric pain syndrome, hamstring injuries, and piriformis syndrome show encouraging improvements in pain and function, including faster return to sport and favorable patient‐reported outcomes. Yet, significant heterogeneity in study design, PRP preparation, and control interventions limits generalizability and hinders clear clinical guidance. These inconsistencies mirror similar challenges in PRP research for a variety of other orthopaedic pathologies, underscoring the need for standardized preparation protocols and consistent reporting frameworks. Despite these limitations, a signal of efficacy persists within the data, suggesting PRP may indeed provide meaningful benefit for select extra‐articular hip conditions. As surgical alternatives for these pathologies often carry substantial morbidity, continued refinement of PRP formulations and methodology represents a promising step toward establishing biologics as reliable, evidence‐based tools in orthopaedic care.

Purpose To develop an expert consensus statement on the diagnosis, management, and rehabilitation of medial meniscal root tears (MMRTs) using a modified Delphi technique. Methods A working group developed statements on MMRT diagnosis, nonoperative management, surgical indications, surgical management, alignment, and rehabilitation using modified Delphi techniques. Fifty‐six experts were surveyed over 3 rounds to reach consensus, with agreement measured on a 5‐point Likert scale. Statements were included, revised, or excluded on the basis of predefined thresholds (≥75% agreement, <20% disagreement). Experts suggested revisions or new statements in the first 2 rounds, and final consensus statements were included. Results All 56 experts completed 3 survey rounds. Experts agreed that root tears may occur with no known history of trauma, typically in older patients, and that it should be diagnosed with an magnetic resonance imaging. In symptomatic patients with MMRTs without advanced osteoarthritis should be repaired using an anatomic transtibial pull‐out technique (performing a pie‐crusting technique can be helpful for visualization). Nonoperative management is advised for patients with advanced osteoarthritis. High tibial osteotomy may be considered for significant varus malalignment during MMRT repair. The only statement without consensus was the management of asymptomatic MMRTs with mild medial compartment cartilage wear, indicating ongoing debate. Conclusions Overall, 98% of statements reached consensus. There is agreement that magnetic resonance imaging is the gold standard for diagnosis. Symptomatic MMRTs without advanced osteoarthritis should be repaired early using an anatomic transtibial pull‐out technique. End‐stage knee osteoarthritis warrants nonoperative management of MMRTs, and a structured postoperative protocol with limited weightbearing and range of motion is essential after repair. No agreement was reached on managing asymptomatic MMRTs in patients without significant medial compartment degeneration. Meniscal centralization sutures may help in cases of substantial extrusion, but their routine use is debated. Level of Evidence Level V, consensus of expert opinion.

Purpose To establish international expert consensus on surgical techniques, complications, and rehabilitation protocols for lateral extra‐articular procedures (LEAPs) performed adjunctively with anterior cruciate ligament reconstruction. Methods Fifty‐five knee surgeons from 17 countries on 5 continents completed a 3‐round modified Delphi process. In the final round, 16 statements on LEAP techniques and complications were scored on a 5‐point Likert scale; ≥75% “agree/strongly agree” constituted consensus. When appropriate, strength of recommendation was graded. Statements lacking support were revised until consensus or abandonment. Results Six statements achieved unanimous consensus (100%), 2 had strong consensus (90%‐99.9%), and 3 reached consensus (75%‐89.9%); 4 were removed. Key technical recommendations were as follows: (1) in iliotibial band procedures, the graft strip should pass beneath the lateral collateral ligament; (2) an anatomic technique is mandatory for anterolateral ligament reconstruction; and (3) no single LEAP is clinically superior to another. Unanimous agreement indicated that modern LEAPs do not increase lateral compartment osteoarthritis risk, carry a low complication rate, and do not necessitate changes to rehabilitation or return‐to‐play timelines. Conclusions Consensus defined core surgical principles and confirmed the safety of adding LEAPs to anterior cruciate ligament reconstruction. When an iliotibial band graft is used, it should be routed deep to the lateral collateral ligament and fixed between 0° and 60° of knee flexion under low tension. For anterolateral ligament reconstruction, femoral fixation should be in full extension at a posterior‐proximal point relative to the lateral epicondyle. Although no single LEAP proved superiority, adherence to these principles permits safe, effective surgery without altering standard rehabilitation or return‐to‐sport protocols and without increasing osteoarthritis risk. Level of Evidence Level V, expert opinion.

Purpose To define expert consensus on whether and how lateral extra‐articular procedures (LEAPs) should accompany anterior cruciate ligament (ACL) reconstruction to optimize outcomes in ACL‐deficient knees. Methods Fifty‐five knee surgeons from 17 countries on 5 continents completed a 3‐round modified Delphi process. Twenty‐one statements on patient selection for combined ACL reconstruction (ACLR) + LEAPs were graded on 5‐point Likert scales; ≥75% “agree/strongly agree” signified consensus. Strength of recommendation was ranked, and statements failing the threshold were revised or discarded after discussion. Results One statement achieved unanimous agreement (100%): it is strongly recommended to add a LEAP for active patients ≤25 years receiving hamstring‐autograft ACLR to reduce graft failure. Strong consensus (≥90%) supported LEAPs in primary ACLR when grade 3 pivot shift (97.9%), knee hyperextension (97.9%), skeletally immature status (79.5%), revision ACLR (91.5%), return to pivoting sports (93.2%), active patients ≤25 years using nonhamstring grafts (90.7%), grade 3 Lachman test (90%), and when multiple relative risk factors coexist (statement 36, 97.1%). Consensus (75%‐89.9%) favored LEAPs for chronic symptomatic ACL deficiency (86.1%), posterior tibial slope >12° (85.7%), and a history of contralateral ACL injury (88.9%). Eight statements did not reach consensus regarding small‐diameter autografts, female athletes, imaging signs of anterolateral injury (e.g., Segond fracture, lateral femoral‐notch sign), and concomitant meniscal procedures. One statement on LEAPs with primary ACL repair was withdrawn because the project focused on reconstruction. Conclusions International experts strongly recommend adding a LEAP in young active patients undergoing hamstring‐autograft ACLR and in cases of high‐grade rotational or anterior laxity, knee hyperextension, revision surgery, or returning to pivoting sports. Unresolved issues include small graft size, female athletes, imaging findings of rotational instability, and concurrent meniscal procedures, highlighting priorities for future research. Level of Evidence Level V, expert opinion.

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.

Background: The microvasculature of the human meniscus has been previously described by Arnoczky and Warren. However, to date, the qualitative and quantitative extra-articular vascular anatomy of the medial meniscus has not been characterized. Purposes: To perform a qualitative and quantitative anatomic study of the extra-articular medial meniscal vasculature and to introduce the novel “medial meniscal artery” (MMA), potentially providing future guidelines for the treatment of meniscal abnormalities. Study Design: Descriptive laboratory study. Methods: A total of 33 unpaired, frozen human cadaveric knees were dissected. The femoral artery was identified and cannulated using an angiocatheter. The arteries were perfused with a red acrylic paint solution, allowing for improved visualization. Artery dimensions and distances were measured using a digital caliper. Perfused specimens were imaged using computed tomography and segmented using 3D reconstruction software to identify vessels and repeat artery measurements digitally. Results: The MMA was consistently identified in all specimens. In 27 (82%) of 33 specimens, the MMA branched directly from the popliteal artery; in 5 (15%), the MMA shared a common trunk with the inferior medial genicular artery; and in 1 specimen (3%), the MMA shared a common branch with the inferior lateral genicular artery. The MMA was easily distinguishable from the superior, inferior, and middle genicular arteries, given its direct course to the medial joint line with terminal branches to the posterior horn of the medial meniscus and deep to the semimembranosus tendon. The MMA exhibited a consistently smaller vessel diameter relative to the genicular arteries. Conclusion: This is the first study to identify and quantitatively describe the MMA in the human knee. The MMA can be identified consistently on gross anatomic dissection in cadaveric donors of varying demographics. Further research is needed to identify and characterize the artery in vivo and to determine the MMA’s role in meniscus preservation surgery. Clinical Relevance: The findings of this study will provide future avenues of research toward understanding medial meniscus vascularization and the genesis of potential degenerative changes when vascularization is poor. This will help to further refine diagnostic and treatment options for meniscus revascularization and compartment preservation. Additionally, this study may help define safe zones in the knee during posterior approaches and expand the base of knowledge for emerging vascular procedures such as genicular artery embolization.

Purpose To evaluate the available literature on the relationship between knee bony morphology and medial meniscus posterior root tears (MMPRTs) to determine which tibiofemoral morphologic risk factors may predispose the development of MMPRTs. Methods Embase, MEDLINE, and PubMed databases were searched to identify all relevant human clinical studies investigating knee morphologic features and MMPRTs. Shape features were compared between control groups and patients with MMPRTs. The methodological index for nonrandomized studies (MINORS) instrument was utilized to assess the methodological quality of included studies. Results Thirteen level III evidence studies and 1 level IV evidence study were included in this review (n = 2,181), with 895 patients in the MMPRT group and 1,286 in the control group. Tibial morphology features associated with an increased risk for MMPRTs included an increased medial tibial slope (6 studies), increased tibial torsion (1 study), increased medial meniscal slope (1 study), and shallower medial tibial plateau concavity (1 study). Varus mechanical alignment was found to increase the risk for MMPRTs (4 studies). Femoral morphology features associated with an increased risk for MMPRTs included an A‐type intercondylar notch (1 study), increased medial femoral condyle (MFC) angle (1 study), narrower intercondylar distance (1 study), narrower intercondylar notch width (1 study), shorter MFC distal offset distance (1 study), increased MFC width (1 study), increased MFC to medial tibial condyle width ratio (1 study), greater distance between the medial tibial eminence and MFC (1 study), and smaller femoral offset ratios of both the medial and lateral condyles (1 study). Conclusions Multiple tibiofemoral shape features, including a steeper slope of the medial tibial plateau, greater varus alignment, and a narrower intercondylar distance and notch width, were found to be predictive factors for MMPRTs. Level of Evidence Level IV, systematic review of Level III and IV studies.

Objectives: The microvasculature of the human meniscus has been previously described by Arnoczky and Warren. However, to date the qualitative and quantitative extra-articular vascular anatomy of the medial meniscus has not yet been characterized. Therefore, the purpose of our study was to perform a qualitative and quantitative anatomic study of the extra-articular medial meniscal vasculature and to introduce the novel “medial meniscal artery” (MMA), potentially providing future guidelines for the treatment of meniscal pathology. Methods: Thirty-three unpaired frozen human cadaveric knees were dissected. The popliteal artery was identified and cannulated with an angiocatheter. The arteries were perfused with a red acrylic paint solution allowing for improved visualization. Artery dimensions and distances were measured using a digital caliper. Perfused specimens were imaged with Computed Tomography scanning and segmented using software to identify vessels and repeat artery measurements. Results: The MMA was consistently identified in all specimens. In 26 of 33 (82%) specimens, the MMA branched directly from the popliteal artery, while in 6, the MMA shared a common trunk with the inferior medial genicular artery (IMGA). The MMA was easily distinguishable from the superior MGA, inferior MGA, and MGA, given its direct course to the medial joint line with terminal branches to the posterior horn of the medial meniscus and deep to the semimembranosus tendon. The MMA exhibited a consistently smaller vessel diameter relative to the genicular arteries. Conclusions: This is the first study identifying and quantitively describing the MMA in the human knee. The MMA can be identified consistently on gross anatomic dissection in patients of varying demographics. The findings of this study will provide future avenues of study toward understanding the medial meniscus vascularization and the genesis of potential degenerative changes when vascularization is poor. This will help to further refine diagnostic and treatment options for meniscus revascularization and compartment preservation. Additionally, this study may help define safe zones in the knee during posterior approaches, as well as furthering the base of knowledge for emerging vascular procedures such as genicular artery embolization. Further research is needed to identify and characterize the artery in vivo and to determine the MMA’s role in meniscus preservation.

Multiligament knee injuries (MLKIs) represent a broad spectrum of pathology with potentially devastating consequences. Currently, disagreement in the terminology, diagnosis and treatment of these injuries limits clinical care and research. This study aimed to develop consensus on the nomenclature, diagnosis, treatment and rehabilitation strategies for patients with MLKI, while identifying important research priorities for further study. An international consensus process was conducted using validated Delphi methodology in line with British Journal of Sports Medicine guidelines. A multidisciplinary panel of 39 members from 14 countries, completed 3 rounds of online surveys exploring aspects of nomenclature, diagnosis, treatment, rehabilitation and future research priorities. Levels of agreement (LoA) with each statement were rated anonymously on a 5-point Likert scale, with experts encouraged to suggest modifications or additional statements. LoA for consensus in the final round were defined ‘a priori’ if >75% of respondents agreed and fewer than 10% disagreed, and dissenting viewpoints were recorded and discussed. After three Delphi rounds, 50 items (92.6%) reached consensus. Key statements that reached consensus within nomenclature included a clear definition for MLKI (LoA 97.4%) and the need for an updated MLKI classification system that classifies injury mechanism, extent of non-ligamentous structures injured and the presence or absence of dislocation. Within diagnosis, consensus was reached that there should be a low threshold for assessment with CT angiography for MLKI within a high-energy context and for certain injury patterns including bicruciate and PLC injuries (LoA 89.7%). The value of stress radiography or intraoperative fluoroscopy also reached consensus (LoA 89.7%). Within treatment, it was generally agreed that existing literature generally favours operative management of MLKI, particularly for young patients (LoA 100%), and that single-stage surgery should be performed whenever possible (LoA 92.3%). This consensus statement will facilitate clinical communication in MLKI, the care of these patients and future research within MLKI.

Objectives: The vascularity of the human meniscus was first famously described by Arnoczky and Warren, who used histological analysis to map out vessel contributions to the medial and lateral menisci. This study determined that the medial and lateral superior and inferior genicular arteries branches give rise to a perimeniscal capillary plexus within the capsular and synovial tissues of the knee. However, since this study, there have been limited investigations into the macro- and microvascularity of the menisci. This includes anatomical, biomechanical, and imaging studies. Doppler ultrasound is an easily accessible, safe, and non-invasive modality that gives clinicians real-time visualization of vascular anatomy. To date, there have been no ultrasound studies that have highlighted vascular deviations from the popliteal artery to the medical meniscus, including the newly discovered medial meniscal artery (MMA), as described in Part 1 of this study (Figure 1, from Part 1 of this investigation). The purpose of this study was to use find a reproducible ultrasound technique to identify the MMA and provide a detailed characterization of the vessel’s precise anatomy. We hypothesized that the MMA would be consistently identifiable in vivo using ultrasound imaging and that multiple anatomic variants of the MMA would exist. Methods: Fifty-six patients underwent ultrasound examination of the left knee. Patient demographics were collected. The MMA was isolated by one of two techniques. In the first approach, the inferior medial genicular artery (IMGA) was isolated and followed back to the popliteal artery, where the examiner then coursed the artery proximally to find medial-sided vasculature branching to the medial meniscus. In the second approach, the probe was started on the medial meniscus and once an arterial supply was found, it was traced back to the popliteal artery. Once the MMA was isolated by either technique, the following variables were measured: presence or absence of MMA, artery diameter, presence of arterial calcifications or atheromatous plaques, and any vascular variations. Once the MMA was found and isolated in the left knee, its presence was investigated in the right knee. Results: The MMA was identified in 50/56 patients (89.2%). The average vessel diameter was 0.89 mm (SD ± 0.39). All 50 patients with a MMA present on the left knee also had the presence of the artery on the right knee. None of the MMA isolated in this study were noted to have any plaques or calcifications. 45 patients were noted to have a Type 1 MMA, whereas five patients were noted to have a Type 2 MMA where the vessel shares an origin with the IMGA (Figure 2). Conclusions: This is the first study to utilize ultrasound to isolate and characterize the MMA in a in vivo human model. The MMA can be consistently seen on ultrasonography in the majority of patients and ultrasound examination demonstrated that the artery perforates into the meniscal tissue to contribute to the meniscal microplexus. The key methods to ensure reproducible identification of the artery and patient characteristics that produce lesser quality images are discussed in detail. Ultrasound identification in clinic may serve as a point-of-care diagnostic modality to determine the likelihood of success of procedures such as medial meniscal repair, given the artery provides a direct blood supply to the meniscus. The MMA may play a pivotal role in meniscal injury, repair, healing, and preservation. Future studies are necessary to determine the extent to which this vessel contributes to said mechanisms.