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Kennedy, Nicholas I.

https://orcid.org/0000-0003-4405-9234

Mayo Clinic

Mayo Clinic

Citations 18

Poster 360: Long-Leg Lateral Monopodal Stress Radiographs for the Assessment of Anterior Tibial Translation with Anterior Cruciate Ligament Injury: A Prospective Study
Otremba, Jace R., Tollefson, Luke V. , Knowlan, Claire J., Kennedy, Nicholas I. , LaPrade, Robert F.

Orthopaedic Journal of Sports Medicine | August 15, 2024 | Volume: 12 | Issue: 7_suppl2 | Pages: No page available

10.1177/2325967124s00326 Get It

Objectives: The purpose of this study is to use standing anterior cruciate ligament (ACL) stress radiographs to evaluate how posterior tibial slope (PTS) compared to anterior tibial translation (ATT) in an injured knee. A secondary purpose was to determine how posterior tibial slope (PTS) affects ATT side-to-side difference. Our hypothesis was that anterior tibial translation would be higher in the injured knee compared to the contralateral side and posterior tibial slope will have a positive effect on anterior tibial translation. Methods: A retrospective study of ACL stress radiographs was assessed from patients with primary ACL reconstructions with no concomitant ligamentous injury between January 2023 and August 2023. Institutional Review Board approval was obtained. The bilateral radiographs were long-leg lateral “stress views” which was accomplished by monopodal weight-bearing in 20° flexion and are a part of the initial patient workup. Stress radiographs were utilized to measure the anterior tibial translation (ATT) and posterior tibial slope (PTS) for both knees. Differences in ATT between knees and the correlation between PTS and ATT was assessed via paired t-tests and regression analysis. Results: A final cohort of 39 patients were analyzed using preoperative ACL stress radiographs. The results reported a significant regression with positive correlation between posterior tibial slope (PTS) and anterior tibial translation for the injured knee using both anatomic (Figure 1, P<0.001, R 2 =0.302) and mechanical (Figure 2, P=0.038, R 2 =0.111) PTS measurements. Anatomic PTS measurements are better at predicting ATT for the injured knee compared to mechanical PTS measurements. Conclusions: The findings of this study report a significant regression with a positive correlation between posterior tibial slope (PTS) and anterior tibial translation (ATT) of the injured knee, with anatomic PTS measurements being a better predictor of ATT than mechanical PTS measurements. This indicates an important relationship between PTS and ATT with higher PTRS predicting higher ATT.
Poster 344: The New "Terrible Triad": Anterior Cruciate Ligament Reconstruction With Concurrent Meniscal Lateral Root and Medial Ramp Repairs
Shoemaker, Evan P , Tollefson, Luke V. , Kennedy, Nicholas I. , Homan, Morgan D. , Shah, Ayush , Sieffert, Kayla J., Wulf, Corey A., Bjerke, Brian, McGaver, Rebecca Stone , Larson, Christopher Michael , LaPrade, Robert F.

Orthopaedic Journal of Sports Medicine | August 15, 2024 | Volume: 12 | Issue: 7_suppl2 | Pages: No page available

10.1177/2325967124s00310 Get It

Objectives: The purpose of this paper was to compare patient reported outcomes (PROMs) between isolated anterior cruciate ligament (ACLR) and ACLR with concomitant medial meniscus ramp and lateral meniscus root repairs and compare PROMs between different medial meniscus ramp and lateral meniscus root repair techniques. Methods: All patients with isolated (ISO) ACL reconstruction or ACL reconstruction with concomitant medial meniscus ramp and lateral meniscus root repairs with a minimum 2 years of follow-up were retrospectively evaluated. Institutional review board approval was obtained for this study. A final total of 42 ISO-ACL patients were matched based upon age, sex, and body mass index to 40 in the “terrible triad” (TT) cohorts. Outcome measures were obtained from 32 patients in the ISO cohort, and 38 patients in the TT cohort. The PROMs used for this study include the International Knee Documentation Committee (IKDC) Subjective Knee, Cincinnati, Tegner, Lysholm, Veterans RAND 12-Item Health Survey (VR-12), and Knee Injury and Osteoarthritis Outcomes Score (KOOS) questionnaire forms. T tests and chi-square goodness of fit tests were used to compare the above PROMs both pre- and postoperatively within each cohort, and between cohorts and rates of revision or reoperation. Results: The preoperative and postoperative PROMs between patients in the isolated cohort and the triad cohort demonstrated no significant differences, except for the Physical category of the VR-12, in which the triad cohort had significantly higher results (p = 0.04) (Figure 1). Both the isolated cohort and the triad cohort reported significant differences between pre- and postoperative PROMs within their own cohorts. When comparing methods of surgery, including all-inside vs. inside-out for the medial meniscus repairs and tunnel versus no-tunnel for the lateral meniscus root repairs, no significant differences were found between postoperative PROMs. Additionally, no significant difference was found in revision or reoperative rates between the triad and isolated cohorts (p = 0.374) (Figure 2), the all-inside versus inside-out medial meniscus cohorts (p = 0.267), or the tunnel vs. no-tunnel lateral meniscus cohorts (p = 0.781). Conclusions: There was no significant difference in PROMs between isolated ACLR versus ACLR with concomitant medial meniscus ramp and lateral meniscus root repairs. While the complexity of the TT ACLR patients was more involved, PROMs and healing rates were similar and performing concurrent medial ramp and lateral root repairs at the time of ACLR should be considered.
Paper 34: Supratubercle Anterior Closing Wedge Osteotomy: No Change in Patellar Height, Compared to Decreased Height for Medial Opening Wedge Proximal Tibial Osteotomy, and Significant Decreases in Anterior Tibial Translation at Six Months Postoperatively
Tollefson, Luke V. , Kennedy, Nicholas I. , Banovetz, Mark T., Homan, Morgan D. , Wulf, Corey A., Engebretsen, Lars , Moatshe, Gilbert , Larson, Christopher Michael , LaPrade, Robert F.

Orthopaedic Journal of Sports Medicine | August 15, 2024 | Volume: 12 | Issue: 7_suppl2 | Pages: No page available

10.1177/2325967124s00046 Get It

Objectives: The purpose of this study was to radiographically assess changes in 1) patellar height, 2) anterior tibial translation (ATT), and 3) posterior tibial slope following supratubercle ACW-PTO and to compare changes in patellar height to a cohort of medial opening proximal tibial osteotomies (MOW-PTO). Methods: Patients who underwent supratubercle ACW-PTO by a single surgeon from July 2019-February 2023 were included. Institutional Review Board approval was obtained for this study. Radiographic assessment at four time points (preoperative, postoperative day 1, 3 months and 6 months) of patellar height (via the Caton Dechamps and Insall Salvati ratios), posterior tibial slope, and anterior tibial translation of the lateral tibial plateau relative to the lateral femoral condyle was completed. A comparison cohort of patients undergoing MOW-PTO was included for comparison of patellar height. Results: Patellar height averages ( n=16) after ACW-PTO using the Caton-Deschamps ratio (Figure 1) demonstrated a significant increase in patellar height on postoperative day 1 ( p=0.004), but were not significantly different at 3 and 6 months postoperatively (Table 2). Conversely, averages of patellar height after MOW-PTO ( n=28) demonstrated no difference on postoperative day 1, but then was significantly decreased by 6 months postoperatively ( p=0.005) (Table 1). There was a significant difference between the closing and opening-wedge cohorts when comparing the difference in patellar height using the CD ratio between preoperative and 6 months ( p=0.011). Anterior tibial translation in the ACW-PTO cohort was significantly decreased by an average of 9.0 mm from preoperative to postoperative values ( p<<0.001) (Figure 2). Posterior tibial slope in the ACW-PTO cohort was significantly decreased by an average of 11.8° from preoperative to postoperative values ( p<<0.001). Conclusions: Supratubercle ACW-PTO performed for ACL failure in the setting of increased tibial slope did not induce significant changes in patellar height postoperatively. Furthermore, following ACW-PTO there was a significant decrease in anterior tibial translation and posterior tibial slope.
Contemporary outcomes of primary total hip arthroplasty in patients with inflammatory arthritis
Wooster, Benjamin M., Kennedy, Nicholas I. , Dugdale, Evan M. , Sierra, Rafael J. , Perry, Kevin I. , Berry, Daniel J. , Abdel, Matthew P. , Abdel, Matthew P , Sierra, Rafael J , Berry, Daniel J

The Bone & Joint Journal | July 1, 2023 | Volume: 105-B | Issue: 7 | Pages: 768-774

10.1302/0301-620x.105b7.bjj-2023-0220.r1 Get It

AimsContemporary outcomes of primary total hip arthroplasties (THAs) with highly cross-linked polyethylene (HXLPE) liners in patients with inflammatory arthritis have not been well studied. This study examined the implant survivorship, complications, radiological results, and clinical outcomes of THA in patients with inflammatory arthritis.MethodsWe identified 418 hips (350 patients) with a primary diagnosis of inflammatory arthritis who underwent primary THA with HXLPE liners from January 2000 to December 2017. Of these hips, 68% had rheumatoid arthritis (n = 286), 13% ankylosing spondylitis (n = 53), 7% juvenile rheumatoid arthritis (n = 29), 6% psoriatic arthritis (n = 24), 5% systemic lupus erythematosus (n = 23), and 1% scleroderma (n = 3). Mean age was 58 years (SD 14.8), 66.3% were female (n = 277), and mean BMI was 29 kg/m2 (SD 7). Uncemented femoral components were used in 77% of cases (n = 320). Uncemented acetabular components were used in all patients. Competing risk analysis was used accounting for death. Mean follow-up was 4.5 years (2 to 18).ResultsThe ten-year cumulative incidence of any revision was 3%, and was highest in psoriatic arthritis patients (16%). The most common indications for the 15 revisions were dislocations (n = 8) and periprosthetic joint infections (PJI; n = 4, all on disease-modifying antirheumatic drugs (DMARDs)). The ten-year cumulative incidence of reoperation was 6.1%, with the most common indications being wound infections (six cases, four on DMARDs) and postoperative periprosthetic femur fractures (two cases, both uncemented femoral components). The ten-year cumulative incidence of complications not requiring reoperation was 13.1%, with the most common being intraoperative periprosthetic femur fracture (15 cases, 14 uncemented femoral components; p = 0.13). Radiological evidence of early femoral component subsidence was observed in six cases (all uncemented). Only one femoral component ultimately developed aseptic loosening. Harris Hip Scores substantially improved (p < 0.001).ConclusionContemporary primary THAs with HXLPE in patients with inflammatory arthritis had excellent survivorship and good functional outcomes regardless of fixation method. Dislocation, PJI, and periprosthetic fracture were the most common complications in this cohort with inflammatory arthritis.Cite this article: Bone Joint J 2023;105-B(7):768–774.
Posterolateral Corner Reconstruction Using Double Femoral Fixation With Adjustable Loop Cortical Suspension and Interference Screw
Kennedy, Nicholas I. , Therrien, Érik , Marx, Robert G. , Levy, Bruce A. , Stuart, Michael J.

Video Journal of Sports Medicine | October 6, 2022 | Volume: 2 | Issue: 5 | Pages: No page available

10.1177/26350254221114890 Get It

Background: The posterolateral corner (PLC) of the knee is a complex anatomic region of the knee comprising the popliteus tendon, the popliteofibular ligament (PFL), and the fibular collateral ligament (FCL). Treatment of PLC injuries is based on the degree of varus and rotational instability on preoperative examination and is recommended in grade 3 injuries. 1,6 Technique Description: The key concept of this new surgical technique is to use adjustable loop cortical suspensory fixation implants for initial femoral fixation of the popliteus and the FCL grafts. This allows for individual tensioning of the grafts prior to definitive fixation with an interference screw. An anatomic fibular tunnel is initially created, followed by popliteus and FCL anatomic femoral socket drilling. A TightRope RT implant is attached to the popliteus end of the graft and secured through a bone tunnel on the medial femoral cortex initially. The popliteus end of the graft is then pulled into the femoral socket before tunneling the graft through the fibular tunnel. A second TightRope RT implant is secured to the FCL end of the graft before securing it to the medial femoral cortex through a bone tunnel and pulling the graft into the drilled femoral socket. An interference screw is first used to secure the graft at the fibular tunnel. The knee is then taken to 60° where the TightRope device is used to remove residual creep and optimize final tensioning prior to final fixation with interference screw in femoral socket. With the knee at 30° of flexion, neutral rotation, and slight valgus, the same steps are repeated for FCL graft. A posterolateral capsular shift is completed for additional stability. Results: Residual posterolateral corner instability or failure after reconstruction surgery has been reported in 6% to 9.4% of surgical reconstruction case. 2,3,5 The use of cortical suspensory devices in PLC reconstructions allows independent dialing of optimal graft tension for both the popliteus and FCL reconstruction before final interference screw fixation, therefore presumably limiting any residual creep and allowing for a double femoral fixation of the graft. Discussion: We describe a novel technique for posterolateral corner reconstruction which allows for optimal and individual tensioning of the structures of the posterolateral corner. Given the technique still uses well-described and validated graft choices and anatomic landmarks for reconstruction, we expect this new technique to allow for similar if not improved outcomes when compared with current gold standard. 4
Benefits of Meniscal Repair in Selected Patients Aged 60 Years and Older
Husen, Martin , Kennedy, Nicholas I. , Till, Sara E., Reinholz, Anna K., Krych, Aaron J. , Saris, Daniël B.F. , Till, Sara, Reinholz, Anna, Krych, Aaron J , Stuart, Michael J.

Orthopaedic Journal of Sports Medicine | September 1, 2022 | Volume: 10 | Issue: 9 | Pages: No page available

10.1177/23259671221117491 Get It

Background: Little is known about the benefits and outcomes of meniscal repair in patients older than 60 years. Purpose: To (1) report the clinical and radiographic outcomes of meniscal repair in patients aged ≥60 years and compare them with matched patients who underwent meniscectomy and (2) identify procedural failures. Study Design: Cohort study; Level of evidence, 2. Methods: We included 32 knees in 32 patients aged ≥60 years (20 female, 12 male; mean age, 64.5 ± 4.6 years) who underwent meniscal repair surgery at a single medical institution between 2010 and 2020. Patients were matched according to age, sex, body mass index, and meniscal tear type with a comparison cohort who underwent meniscectomy (n = 49 patients [49 knees]; 32 female, 17 male). For all patients, demographic information, clinical history, physical examination findings, treatment details, and radiographic images were reviewed and analyzed. At final follow-up (mean, 42.2 months; range, 13-128 months), patients completed the 2000 International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Knee injury and Osteoarthritis Outcome Score (KOOS), and Lysholm score. Clinical failure was defined as revision surgery and/or progression to total knee arthroplasty (TKA). A matched-pairs t test was used to analyze differences between the 2 treatment groups, and Kaplan-Meier analysis was used to determine the rates of knee osteoarthritis and progression to TKA. Results: The majority of patients had a medial meniscal tear (72.8%), whereas the lateral meniscus was torn in 27.2% of cases. Most tears were located in the meniscal root (56.8%), followed by the posterior horn (34.6%) and midbody (8.6%). At final follow-up, all outcome scores were higher in the repair group compared with the meniscectomy group (IKDC, 78.9 ± 13.4 vs 56.0 ± 15.4; KOOS, 86.6 ± 11.9 vs 61.7 ± 16.2; Lysholm, 88.3 ± 13.3 vs 68.7 ± 15.2, respectively; P < .001 for all). Clinical failure was observed in 22% of patients in the repair group. Conclusion: All clinical outcome scores were higher in the meniscal repair group compared with the matched meniscectomy group at final follow-up. The clinical failure rate of the repair group was 22%. These findings support meniscal repair in selected patients aged ≥60 years.
Complex Patellofemoral Reconstruction for Recurrent Instability
Floyd, Edward R. , Kennedy, Nicholas I. , Tagliero, Adam J. , Carlson, Gregory B. , Tagliero, Adam , Floyd, Edward R. , LaPrade, Robert F.

Video Journal of Sports Medicine | January 4, 2022 | Volume: 2 | Issue: 1 | Pages: No page available

10.1177/26350254211035396 Get It

Background: Patellofemoral instability is due to a combination of bony and soft tissue factors. While recurrent patellar dislocations are rare, evaluation and treatment of these conditions require addressing patellar height and lateralization of the tibial tubercle (TT), restraint to lateral patellar subluxation, and trochlear dysplasia. Other factors to consider are coronal limb-length alignment outside of the physiologic 5 to 8° of valgus, which may significantly alter the Q angle and contribute to lateral instability. Other ligaments around the patella contribute to soft-tissue restraint, including the medial and lateral patellotibial ligaments, patellomeniscal ligaments, and the medial quadriceps tendon femoral ligament. Patellar tilt is assessed with and without quadriceps contraction to further evaluate the patella’s relationship to the trochlear groove. The Caton-Deschamps Index, as well as patellar trochlear index (PTI), are used to measure patellar height for patella alta or baja. Technique Description: The technique is to surgically manage a patient in neutral mechanical alignment on standing limb radiographs, with moderate-to-severe DeJour type B trochlear dysplasia and a trochlear sulcus angle of around 145°, patella alta with a Caton-Deschamps Index of 1.6 and PTI of 0.22, a TT to trochlear groove (TT-TG) distance of 8 mm, and a deficient medial patellofemoral ligament (MPFL). The MPFL reconstruction is done first, with harvesting of the ipsilateral quadriceps tendon and maintenance of its distal attachment on the superior patellar pole. The quadriceps tendon graft is folded medially upon its distal attachment and fixed in this position with suture anchors. Tibial tubercle osteotomy is accomplished by spacing drill holes 2 mm apart, medially and laterally, on the TT and connecting the drill holes with an osteotome and reciprocating saw. A distalized location to secure the TT is selected and superficial bone is excised. A medial parapatellar arthrotomy is performed, and bur attachments are used to drill into the subchondral bone beneath the femoral articular surface to create a V-shaped flap of trochlear cartilage. An arthroscope is inserted under the trochlear flap during this process to visualize the appropriate depth. The trochlear flap is then secured with screws passed over guide pins to secure the flap to the desired location. Cannulated screws and washers are then used to secure the TT to its distalized and/or medialized position, with fluoroscopic verification of screw depth and location. The arthrotomy is then closed with the knee at 45°. The quadriceps graft is passed through a subretinacular channel and secured with suture anchors, adjacent to the adductor tubercle, to complete the MPFL reconstruction. Before closure, appropriate tracking and translation of the patella is verified. Results: Sulcus-deepening trochleoplasty, with or without MPFL reconstruction, has been reported to obtain satisfactory outcomes at 2 years, with close to 85% return to sport and 100% return to work, with improvements in International Knee Documentation Committee (IKDC) scores from 50.8 to 79.1 in some studies. MPFL reconstruction with tibial tubercle osteotomy (TTO) has yielded a 94.5% patient satisfaction rate in the literature. Discussion/Conclusion: In patients with recurrent patellar instability and DeJour types B-D trochlear dysplasia, MPFL reconstruction with TTO and sulcus-deepening trochleoplasty provides excellent subjective outcomes and restores patellar tracking with elimination of recurrent subluxation.
Change in Posterior Tibial Slope in Skeletally Immature Patients With Anterior Cruciate Ligament Injury: A Case Series With a Mean 9 Years’ Follow-up
Martin, R. Kyle , Ekås, Guri Ranum , Benth, Jūratė Šaltytė , Kennedy, Nicholas I. , Krych, Aaron J. , Kennedy, Nicholas, Krych, Aaron J , Moatshe, Gilbert , Engebretsen, Lars

The American Journal of Sports Medicine | March 8, 2021 | Volume: 49 | Issue: 5 | Pages: 1244-1250

10.1177/0363546521997097 Get It

Background: Increased lateral posterior tibial slope (LPTS) is associated with increased rates of anterior cruciate ligament (ACL) injury and failure of ACL reconstruction. It is unknown if ACL deficiency influences the developing proximal tibial physis and slope in skeletally immature patients through anterior tibial subluxation and abnormal force transmission. Purpose: To assess the natural history of LPTS in skeletally immature patients with an ACL-injured knee. Study Design: Case series; Level of evidence, 4. Methods: A total of 38 participants from a previous study on nonoperative management of ACL injury in skeletally immature patients were included. During the initial study, bilateral knee magnetic resonance imaging (MRI) was performed within 1 year of enrollment and again at final follow-up. All patients were younger than 13 years at the time of enrollment, and final follow-up occurred a mean 10 years after the injury. MRI scans were retrospectively reviewed by 2 reviewers to determine bilateral LPTS for each patient and each time point. Linear mixed models were used to assess LPTS differences between knees, change over time, and association with operational status. Subgroup analyses were performed for patients who remained nonoperated throughout the study. Results: A total of 22 patients had ACL reconstruction before final follow-up and 16 remained nonoperated. In the entire study population, the mean LPTS was higher in the injured knee than in the contralateral knee at final follow-up by 2.0° ( P < .001; 95% CI, 1.3°–2.6°). The mean LPTS increased significantly in the injured knee by 0.9° ( P = .042; 95% CI, 0.03°–1.7°), while the mean LPTS decreased in the contralateral knee by 0.4° ( P = .363; 95% CI, –0.8° to 0.4°). A significant difference in LPTS was also observed in the nonoperated subgroup. No significant association was observed between LPTS and operational status. Conclusion: Lateral posterior tibial slope increased more in the ACL-injured knee than in the contralateral uninjured knee in a group of skeletally immature patients. Lateral posterior tibial slope at baseline was not associated with the need for surgical reconstruction over the study period.
Arthroscopic Identification of the Knee Posterolateral Corner Structures and Anatomic Arthroscopic Posterolateral Corner Reconstruction: Technical Note – Part 2
Freychet, Benjamin , Sonnery‐Cottet, Bertrand , Vieira, Thaïs Dutra , Sanders, Thomas L. , Kennedy, Nicholas I. , Krych, Aaron J. , Stuart, Michael J. , Levy, Bruce A. , Krych, Aaron J , Stuart, Michael J

Arthroscopy Techniques | December 21, 2020 | Volume: 9 | Issue: 12 | Pages: No page available

10.1016/j.eats.2020.08.033 Get It

Abstract Posterolateral corner injuries are complex injuries, and their therapeutic management varies from one individual to another. Biomechanical studies demonstrate that anatomic posterolateral corner reconstruction restores knee kinematics better than nonanatomic reconstruction. The purpose of this report is to describe an all‐arthroscopic procedure for anatomic posterolateral corner reconstruction. Technique Video video See video under supplementary data.
Arthroscopic Identification of the Knee Posterolateral Corner Structures and Anatomic Arthroscopic Posterolateral Corner Reconstruction: Technical Note – Part 1
Freychet, Benjamin , Sonnery‐Cottet, Bertrand , Sanders, Thomas L. , Kennedy, Nicholas I. , Krych, Aaron J. , Levy, Bruce A. , Krych, Aaron J , Vieira, Thaïs Dutra , Stuart, Michael J.

Arthroscopy Techniques | December 21, 2020 | Volume: 9 | Issue: 12 | Pages: No page available

10.1016/j.eats.2020.08.026 Get It

Abstract Arthroscopic assessment of posterior compartments of the knee and the posterior aspect of the proximal tibial and fibula is challenging because of the relative proximity of the neurovascular bundle. This Technical Note describes a reproducible arthroscopic surgical approach in a cadaveric model that aims to identify and expose the popliteus tendon, posterior fibular head, fibular collateral ligament popliteal fibular ligament, biceps femoris tendon, and peroneal nerve. Technique Video video See video under supplementary data.