Partial Lateral Meniscectomy Research Articles

The Contribution of Partial Meniscectomy to Preoperative Laxity and Laxity After Anatomic Single-Bundle Anterior Cruciate Ligament Reconstruction: In Vivo Kinematics With Navigation

Background: Limited in vivo kinematic information exists on the effect of clinical-based partial medial and lateral meniscectomy in the context of anterior cruciate ligament (ACL) reconstruction. Hypothesis: In patients with ACL deficiency, partial medial meniscus removal increases the anteroposterior (AP) laxity with compared with those with intact menisci, while partial lateral meniscus removal increases dynamic laxity. In addition, greater postoperative laxity would be identified in patients with partial medial meniscectomy. Study design: Cross-sectional study; Level of evidence, 3. Methods: A total of 164 patients with ACL tears were included in the present study and divided into 4 groups according to the meniscus treatment they underwent: patients with partial lateral meniscectomy (LM group), patients with partial medial meniscectomy (MM group), patients with partial medial and lateral meniscectomy (MLM group), and patients with intact menisci who did not undergo any meniscus treatment (IM group). A further division in 2 new homogeneous groups was made based on the surgical technique: 46 had an isolated single-bundle anatomic ACL reconstruction (ACL group), while 13 underwent a combined single-bundle anatomic ACL reconstruction and partial medial meniscectomy (MM-ACL group). Standard clinical laxities (AP translation at 30° of knee flexion, AP translation at 90° of knee flexion) and pivot-shift (PS) tests were quantified before and after surgery by means of a surgical navigation system dedicated to kinematic assessment. The PS test was quantified through 3 different parameters: the anterior displacement of the lateral tibial compartment (lateral AP); the posterior acceleration of the lateral AP during tibial reduction (posterior acceleration); and finally, the area included by the lateral AP translation with respect to the flexion/extension angle (area). Results: In the ACL-deficient status, the MM group showed a significantly greater tibial translation compared with the IM group (P < .0001 for AP displacement at 30° [AP30] and 90° [AP90] of flexion) and the LM group (P = .002 for AP30 and P < .0001 for AP90). In the PS test, the area of LM group was significantly larger (57%; P = .0175) than the one of the IM group. After ACL reconstruction, AP translation at 30° was restored, while the AP90 remained significantly greater at 1.3 mm (P = .0262) in the MM-ACL group compared with those with intact menisci. Conclusion: Before ACL reconstruction, partial medial meniscectomy increased AP laxity at 30° and 90° and lateral meniscectomy increased dynamic PS laxity with respect to intact menisci. Anatomic single-bundle ACL reconstruction decreased laxities, but a residual anterior translation of 1.3 mm at 90° remained in patients with partial medial meniscectomy, with respect to those with intact menisci.

Incidence of Symptomatic Pulmonary Embolus and Deep Vein Thrombosis After Knee Arthroscopy in the Pediatric and Adolescent Population.

The incidence of deep venous thrombosis (DVT) and pulmonary embolism (PE) after pediatric knee arthroscopy is unknown. The purpose of this study was to determine the incidence of venous thromboembolism (VTE) after knee arthroscopy in the pediatric and adolescent population in a high-volume center. Retrospective cohort study. Tertiary care children's hospital. All patients who underwent arthroscopy of the knee for a sports-related injury by 2 surgeons were reviewed. Chief complaint, past medical/surgical history, medications, procedure performed, intraoperative findings, intraoperative complications, and postoperative recovery were reviewed. The incidences of postoperative VTE within 30 days after the procedure were reviewed. Seven hundred forty-six (358 male and 388 female patients) knee arthroscopies performed from September 2011 to October 2016 by 2 pediatric orthopedic surgeons specializing in sports-related injuries were included. The average age was 15.2 ± 2.72 years. Five patients were suspected to have either DVT or PE postoperatively (0.67%). The overall incidence of symptomatic confirmed VTE after knee arthroscopic procedures was 0.27% (one DVT after a partial lateral meniscectomy and one PE after fixation of an osteochondral lesion). The incidence of VTE after pediatric sports medicine knee arthroscopies is low, 0.27%. Patients who present with calf swelling or pain, chest pain, or shortness of breath after arthroscopic surgery should be examined closely. Level III.

High Rate of Recurrent Meniscal Tear and Lateral Compartment Osteoarthritis in Patients Treated for Symptomatic Lateral Discoid Meniscus: A Population-Based Study.

Background:Little is known about the natural history of a surgically treated symptomatic lateral discoid meniscus. The goals of this study were to describe the rate and factors associated with recurrent lateral meniscal tears and progression to symptomatic lateral compartment osteoarthritis (OA) in patients surgically treated for a symptomatic lateral discoid meniscus.Hypothesis:Patients with surgically treated lateral discoid meniscus have a high incidence of meniscal retear and progression to lateral compartment OA.Study Design:Case series; Level of evidence, 4.Methods:A large geographic database was reviewed to identify and confirm patients presenting with symptomatic lateral discoid meniscus between 1998 and 2015. Charts were reviewed to document treatment and outcomes at a minimum clinical follow-up of 2 years.Results:A total of 59 patients (27 females, 32 males) with a mean age of 25.7 years (range, 4.0-66.0 years) underwent surgical management of a discoid lateral meniscus and were evaluated for a mean of 5.6 years (range, 2.0-23.7 years). Of these, 48 (82%) patients underwent partial lateral meniscectomy, with 24 patients undergoing concurrent saucerization. Eleven (18%) underwent meniscal repair. Tear-free survival following surgery was 41% at 8 years. Progression to symptomatic lateral compartment OA was 50% at 8 years. Young age (hazard ratio, 0.96; 95% CI, 0.93-0.99; P = .01) and open growth plates (hazard ratio, 3.19; 95% CI, 1.15-8.88; P = .03) were associated with increased incidence of postoperative retear. Older age at diagnosis and body mass index ≥30 kg/m2 were associated with increased risk of progression to lateral compartment OA on final radiographs.Conclusion:Patients with a surgically treated lateral discoid meniscal tear had a high rate of recurrent meniscal tear (59% at 8 years). Approximately 50% of surgically treated patients developed symptomatic lateral compartment OA at 8 years from diagnosis.

High Rate of Recurrent Meniscus Tear and Lateral Compartment Osteoarthritis in Patients Treated for Symptomatic Lateral Discoid Meniscus: A Long-Term Population-Based Study

Objectives: Little is known about the natural history and long-term outcome of a surgically treated symptomatic lateral discoid meniscus. The goals of this study were to describe the rate and factors associated with recurrent lateral meniscus tears and progression to symptomatic lateral compartment osteoarthritis (OA) in patients surgically treated for a symptomatic lateral discoid meniscus. Patients with surgically treated lateral discoid meniscus have a high incidence of meniscus re-tear and progression to lateral compartment OA. Methods: A large, geographic database was reviewed to identify and confirm patients presenting with symptomatic lateral discoid meniscus between 1998 and 2015. Charts were reviewed to document treatment and outcomes at a minimum clinical follow-up of two years. Results: 70 discoid meniscus patients (30 F, 40 M) with a mean age of 27 years (Range: 2.0-66.0) were followed for an average of 5.8 years (Range 2.0-23.7). Sixty patients underwent surgical management: 49 (82%) patients underwent partial lateral meniscectomy and 11 (18%) underwent meniscus repair (including saucerization). Tear-free survival following surgery was 93% at 2 years, 69% at 5 years, and 40% at 8 years. Overall progression to symptomatic lateral compartment OA in the surgical group was 10% at 2 years, 23% at 5 years, and 48% at 8 years. Of those patients who developed lateral compartment OA, 55% (11/20) had a Kellgren-Lawrence score 2 or greater at last radiographic follow-up. Young age and open growth plates were associated with increased incidence of postoperative re-tear (HR: 0.96, CI: 0.93-0.99, p = 0.01). Increased age at diagnosis and BMI ≥ 30 were associated with increased risk of progression to lateral compartment OA on final radiographs. Conclusion: Patients with a surgically treated lateral discoid meniscus tear had a high rate of recurrent meniscus tear at long-term follow-up (60% at 8 years) that was associated with young age. Approximately 48% of surgically treated patients developed symptomatic lateral compartment OA at eight years from initial presentation. The risk of progression to OA increased with older age at diagnosis and BMI ≥ 30.

PARTIAL TRANSPHYSEAL ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: CLINICAL, FUNCTIONAL, AND RADIOGRAPHIC OUTCOMES

BACKGROUND Partial transphyseal anterior cruciate ligament (ACL) reconstruction is a technique utilized in the skeletally immature population. The femoral tunnel is placed in the distal femoral epiphysis whereas the tibial tunnel is placed in a transphyseal fashion medial to the tibial tubercle. This technique was introduced in an effort to lessen insult to the distal femoral physis of skeletally immature adolescents while also avoiding the technical difficulty of placing an intra-epiphyseal tunnel in the proximal tibia which at times can be non-anatomic. There is limited literature examining this technique. In this study we analyzed the concurrent surgical procedures, re-operation and graft failure rates, and radiographic outcomes in adolescents undergoing partial transphyseal ACL reconstruction. METHODS Consecutive patients undergoing partial transphyseal ACL reconstruction by the two senior authors (NP and CA) were retrospectively reviewed. Inclusion criteria consisted of patients with symptomatic ACL rupture with open distal femoral physes and at least two years of growth remaining by chronologic and physiologic age as determined by growth and pubertal history. All patients received hamstring autograft. Femoral tunnels were drilled in an intra-epiphyseal location utilizing small angle guides under fluoroscopic guidance. Transphyseal tibial tunnels were drilled in standard fashion with a tip-aiming guide while minimizing thermal damage from slow reaming, avoiding horizontal tunnel placement, and using extraphyseal graft fixation to lessen insult to the proximal tibial physis. Radiographic outcomes including bilateral limb length (LL) and alignment as judged by mechanical axis deviation (MAD), mechanical lateral distal femoral angle (mLDFA), and medial proximal tibial angle (MPTA) were measured on long standing anterior-to-posterior (AP) view radiographs. Growth disturbance was defined as = 1 cm leg length discrepancy, = 1 cm difference in MAD, or 5-degree difference in mLDFA or MPTA as compared to the non-operative side and MAD/mLDFA/MPTA outside of established range of normal values. Clinical outcomes including graft failure and need for repeat operation were recorded at each follow-up visit. Operative extremity alignment measurements were compared to non-operative extremity measurements utilizing a paired students t-test. RESULTS Twenty-four patients with average follow up of 31.5 ± 17.1 months met inclusion criteria for this study. Five female and 19 male patients were enrolled consisting of 13 left and 11 right knees. Average age at time of surgery was 12.3 ± 0.9 years (10.1-13.8 years). The average ACL graft size was 7.8 mm ± 0.5 mm (6-9 mm). Ten patients (41.7%) had concurrent meniscal surgery, with seven (29.2%) undergoing partial lateral meniscectomy, two (8.3%) lateral meniscus repairs, and one patient (4.2%) with medial and lateral meniscal repairs. Six patients (25.0%) required re-operation at an average of 29.2 ± 17.3 months (1.5-49.5 months) for removal of hardware (n=3), revision ACL reconstruction (n=2), and meniscus surgery (n=1). Two patients had ACL graft failure (8.3%) during sporting activity and underwent revision ACL reconstruction at 19.7 months and 49.5 months post-operatively. There were no contralateral ACL tears. As shown in Table 1, comparison of the mean alignment and limb length measurements between all patients’ operative to nonoperative extremity revealed no significant difference in femur length, MAD, MLDFA, or MPTA. There was a small but statistically significant difference in operative versus non-operative tibia length (390.2 cm versus 392.4 cm, p=0.0004) and limb length (880.9 cm versus 884.0 cm, p=0.02). In analyzing individual patients’ limb length or alignment differences, five patients (20.8%) were identified with a growth disturbance. One patient had isolated shortening of the operative extremity, two with significant lateral deviation of the MAD, and two with both shortening and lateral MAD translation. No patients had significant side-to-side difference in mLDFA or MPTA. Femoral shortening accounted for the majority of the limb length discrepancy in two of the three patients with significant limb length discrepancy. All patients returned to sport. CONCLUSIONS / SIGNIFICANCE Partial transphyseal ACL reconstruction has a 25.0% re-operation rate, most often for hardware removal, and an 8.3% graft failure rate. Overall, approximately 20% of patients undergoing partial transphyseal ACL reconstruction had a growth disturbance but none required surgical intervention for these disturbances. While the partial transphyseal technique spares the distal femoral physis, femur-dominant limb length discrepancy can still occur. Drilling and graft placement across the tibial physis appears to be safe. Further studies are needed to directly compare the radiographic, functional, and clinical outcomes of partial transphyseal ACL reconstruction with transphyseal and all-epiphyseal techniques in the pediatric population. [Table: see text]

Partial meniscectomy adversely affects return-to-sport outcome after anatomical double-bundle anterior cruciate ligament reconstruction.

The purposes of this study were to determine whether the partial meniscectomy combined with ACL reconstruction affect the postoperative return-to-sport and to identify if partial meniscectomy has an influence on the graft failure following an anatomical double-bundle ACL reconstruction case. A retrospective cohort study including 426 primary double bundle ACL reconstruction cases. There were 206 males and 220 females, median age of 28.4years, median BMI of 23.0, median preinjury Tegner score of 7.0 and median follow-up period after surgery of 24.0months. Patients with less than 12months of follow-up, revision surgery, multi-ligaments injury, previous contralateral knee ligaments injury and postoperative infection cases were excluded. Furthermore, patients who had meniscal repair were excluded in order to compare the outcomes between patients who had intact menisci and those who underwent partial meniscectomy. There were 227 patients with intact menisci (group A) and 199 patients with partial meniscectomy (group B). The median age was younger and the preoperative Tegner score was higher in group A. The patients in group B were subcategorized as the site of partial meniscectomy, including medial (group C), lateral (group D) and bicompartmental (group E) meniscectomy. There were 74, 94, and 31 patients in group C, D, and E, respectively. Return-to-sport (running and sport phase) and graft failure were included in our primary outcomes, and functional outcome as Lysholm knee scores was included in secondary outcome. The rate of return to running phase and sport phase were 91% (387/426) and 76% (303/399), the mean time taken to return to running and sport phase were 5.7months and 11.1months, respectively. There was significant difference in the returning to sport phase between group A and B (p=0.01), and between group A and D/E subgroups (p=0.007). There were fourteen graft failures (3.5%) in total. In addition, 9 and 5 graft failures in group A and B, respectively. Of the 5 graft failures in group B, 2 and 3 graft failures in group C and D, respectively. There was no significant difference of the graft failure ratio among the groups. Our study demonstrates that partial meniscectomy has an adverse effect on the return to sport phase following the anatomical double-bundle ACL reconstruction. Therefore, greater postoperative care would be needed to return to sport with partial meniscectomy in ACL reconstruction cases. On the contrary, partial meniscectomy is not considered to be the risk factor for graft failure at short-term follow-up. Case-control study, Level III.

Incidence and Treatment Trends of Symptomatic Discoid Lateral Menisci: An 18-Year Population-Based Study.

Background:A symptomatic discoid lateral meniscus is an uncommon orthopaedic abnormality, and the majority of information in the literature is limited to small case series.Purpose/Hypothesis:The purpose of this study was to determine the incidence of symptomatic discoid menisci in a geographically determined population and to describe treatment trends over time. The hypothesis was that the incidence of symptomatic discoid menisci would be highest among adolescent patients, and thus, the rate of surgical treatment would be high compared with nonoperative treatment.Study Design:Descriptive epidemiology study.Methods:The study population included 79 patients in Olmsted County, Minnesota, identified through a geographic database, who were diagnosed with a symptomatic discoid lateral meniscus between 1998 and 2015. The complete medical records were reviewed to confirm the diagnosis and evaluate the details of injury and treatment. Age- and sex-specific incidence rates were calculated and adjusted to the 2010 United States population.Results:The overall annual incidence of symptomatic discoid lateral menisci was 3.2 (95% CI, 2.5-3.9) per 100,000 person-years; 12.6% of the patients in the cohort had bilateral symptomatic discoid lateral menisci. The overall annual incidence was similar between male (3.5 per 100,000 person-years) and female patients (2.8 per 100,000 person-years). The highest incidence of symptomatic discoid lateral menisci was noted in adolescent male patients aged 15-18 years (18.8 per 100,000 person-years). A majority (72.2%) of patients presented with a symptomatic tear of the discoid meniscus. The remaining patients presented with mechanical symptoms, including catching/locking or effusion, with no demonstrable meniscus tear on imaging or diagnostic arthroscopic surgery. Additionally, 20.0% of patients were observed to have peripheral instability of the meniscus at the time of diagnostic arthroscopic surgery. The mean age of those with peripheral instability was significantly younger than of those who did not have peripheral instability. Sixty patients (75.9%) received surgical treatment during the study period, including 49 (81.7%) patients who underwent partial lateral meniscectomy and 11 (18.3%) patients who underwent lateral meniscus repair in addition to saucerization.Conclusion:With an overall annual incidence of 3.2 per 100,000 person-years, a symptomatic discoid meniscus is an uncommonly encountered orthopaedic abnormality. However, the incidence of symptomatic discoid lateral menisci is highest in adolescent male patients. Because of the high rate of meniscus tears in patients presenting with symptoms, the majority are treated surgically.

Adipose-to-muscle area ratio at the knee is superior to BMI in predicting post-operative outcome following arthroscopic meniscectomy

To determine if measurement of leg adipose tissue area by MRI is a better predictor of post-operative clinical outcome compared to body mass index (BMI) following arthroscopic meniscectomy. Patients that underwent an arthroscopic partial meniscectomy between 2011 and 2016 were identified and a retrospective chart review was performed. Patients with additional knee pathology other than a meniscal tear with or without associated articular cartilage injury were excluded. Leg adipose tissue and muscle area measurements at the level of the knee joint were performed for patients on their preoperative axial magnetic resonance imaging (MRI) study and adipose-to-muscle area ratio (AMR) was calculated. Correlations among AMR, BMI, and post-operative clinical outcomes were compared. A total of 74 patients (32 females and 42 males) were included (mean age 50.0 years, std. dev. 12.3years). 35 patients underwent a partial medial meniscectomy, 15 underwent a partial lateral meniscectomy, and 24 underwent both. Linear regression analysis showed that the AMR, compared to BMI, had a significantly stronger correlation to both mean post-operative Knee Injury and Osteoarthritis Outcome Score (KOOS) across all 5 subscales (KOOS5) and Tegner Current score. Patients that had cartilage damage and concurrent chondroplasty tended to be older and have lower post-operative KOOS5 compared to those with no cartilage damage. AMR was also significantly correlated to age and BMI. The current study demonstrates that compared to BMI, leg adiposity as determined by the ratio of adipose tissue to muscle area on axial MRI (AMR), is a stronger predictor of functional outcome following meniscectomy. This suggests a role of obesity in the progression of OA beyond the increased joint forces associated with increased BMI. IV, retrospective case series.

Risk factors for progression of articular cartilage damage after anatomical anterior cruciate ligament reconstruction: a second-look arthroscopic evaluation.

To investigate the risk factors for progression of articular cartilage damage after anatomical anterior cruciate ligament (ACL) reconstruction. A total of 174 patients who underwent second-look arthroscopic evaluation after anatomical ACL reconstruction were enrolled in this study. The graded condition of the articular cartilage at the time of ACL reconstruction was compared with that at second-look arthroscopy. Age, gender, body mass index (BMI), ACL reconstruction technique, meniscal conditions, and other variables were assessed by regression analysis as risk factors for progression of damage to the articular cartilage. In the medial compartment, multivariable logistic regression analysis indicated that partial medial meniscectomy (odds ratio (OR) 6.82, 95% confidence interval (CI) 2.11 to 22.04, p = 0.001), pivot-shift test grade at the final follow-up (OR 3.53, CI 1.39 to 8.96, p = 0.008), BMI (OR 1.15, CI 1.03 to 1.28, p = 0.015) and medial meniscal repair (OR 3.19, CI 1.24 to 8.21, p = 0.016) were significant risk factors for progression of cartilage damage. In the lateral compartment, partial lateral meniscectomy (OR 10.94, CI 4.14 to 28.92, p < 0.001) and side-to-side differences in anterior knee laxity at follow-up (OR 0.63, p = 0.001) were significant risk factors. Partial meniscectomy was found to be strongly associated with the progression of articular cartilage damage despite r anatomical ACL reconstruction. Cite this article: Bone Joint J 2018;100-B:285-93.

Diagnosis and Management of Postoperative Conversion Disorder in an Adolescent Following Arthroscopic Meniscectomy

Conversion disorder (CD), also known as a functional neurological symptom disorder, is a somatoform disorder involving an unconscious, involuntary process in which psychosocial needs, conflicts, and internal stresses are expressed as somatic symptoms without an anatomical or physiological explanation. The signs and symptoms are involuntary and appear with no underlying physical cause. Various triggers and psychologic stresses may result in the sudden clinical manifestations of the disorder. We present a 14-year-old adolescent who developed a CD following anesthetic care for a partial lateral meniscectomy. Previous reports of postoperative CDs are reviewed, etiologic considerations during the postoperative period are discussed, and management options are presented. J Med Cases. 2017;8(10):326-329 doi: https://doi.org/10.14740/jmc2905w

Risk factors for radiographic joint space narrowing and patient reported outcomes of post-traumatic osteoarthritis after ACL reconstruction: Data from the MOON cohort.

The Multicenter Orthopaedic Outcomes Network (MOON) is an NIH-funded prospective, longitudinal cohort of over 3,500 patients who have undergone anterior cruciate ligament reconstruction (ACLR) by 14 sports medicine surgeons at 7 academic medical centers. Patient reported outcome questionnaires (PRO's) are completed at baseline and multiple timepoints after surgery, and a nested cohort of patients return for radiographs to assess the development of joint space changes. We review the risk factors for worse patient reported outcomes, the predictors of clinically significant symptoms of post-traumatic osteoarthritis (PTOA), and the factors associated with more radiographic joint space narrowing. Baseline PRO's were highly predictive of follow-up scores. Factors associated with worse PRO's at 2 and 6 years included female sex, higher BMI, smoking, less education, allograft, medial meniscectomy, or repair, and chondral injury. Partial lateral meniscectomy was unexpectedly associated with better PRO's. Factors associated with clinically significant symptoms of PTOA at 2 and 6 years included subsequent surgery, meniscal pathology, and chondral injury. Factors associated with narrower medial compartment joint space width included medial meniscectomy, medial meniscus repair, and increased age. Medial joint space width was slightly wider overall for the ACLR knees compared to the contralateral normal knees. Future studies will evaluate PRO's and radiographs at 10-year follow-up. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1366-1374, 2017.

Successful Return to Sport Following Distal Femoral Varus Osteotomy

Objectives:Distal femoral varus osteotomy is an effective treatment for unloading valgus knee malalignment; however, there is limited evidence on the ability for patients to return to athletics following this procedure. The purpose of this study is to report the functional outcomes and return to sport for athletic patients that underwent distal femoral varus osteotomy.Methods:A consecutive series of athletic patients that had undergone distal femoral varus osteotomy for symptomatic lateral compartment overload and valgus knee malalignment were prospectively reviewed. All patients had a minimum of 2-year follow-up. Radiographs were assessed to determine pre-operative and post-operative alignment. Details regarding sport of interest, ability to return to sport, and timing of return were obtained from the patients. Prospective institutional registries were utilized to collect pre-operative and post-operative Marx Activity Scale and International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC) scores; these values were compared using paired t-tests with p < 0.05 as the threshold for significance.Results:A total of 13 patients with a mean age of 24 years (range: 17-35) and a mean follow-up of 43 months (range: 24-74) were included in the study. Six patients underwent medial closing wedge osteotomy, and seven patients underwent lateral opening wedge osteotomy. The mean alignment correction was 8 degrees (range: 5-13). Nine patients underwent one or more concomitant procedures at the time of the osteotomy: 6 lateral femoral condyle osteochondral allografts, 2 partial lateral meniscectomies, 1 lateral meniscus allograft transplantation, and 1 revision anterior cruciate ligament reconstruction. All patients were able to successfully return to their sport of choice (4 soccer, 2 softball, 2 running, 1 football, 1 basketball, 1 ice hockey, 1 volleyball, 1 rowing) at a mean of 11 months (range: 9-13). Furthermore, all 13 patients demonstrated an improvement in both Marx Activity Scale and IKDC scores after surgery. The mean improvement in Marx Activity Scale was 7 (mean pre-op: 4, mean post-op: 11, p < 0.01), and the mean improvement in IKDC score was 36 (mean pre-op: 53, mean post-op: 89, p < 0.01).Conclusion:Valgus knee malalignment results in overload of the lateral compartment and can severely limit one’s ability to participate in athletic activities. Correction of valgus knee malalignment through distal femoral varus osteotomy - either medial closing wedge or lateral opening wedge - can reliably result in improvement in function and return to sport, provided that concomitant chondral, meniscal, and ligamentous pathology is addressed. Therefore, distal femoral varus osteotomy should be considered in the athletic population for correction of symptomatic valgus knee malalignment.

Predictors of Lateral Compartment Joint Space Difference at a Minimum of Two Years after ACL Reconstruction

Objectives:ACL reconstruction effectively restores knee stability and allows a return to athletic activities after ACL injury, but patients are still at higher risk of developing post-traumatic OA. Patient reported outcomes from the Multicenter Orthopaedic Outcomes Network (MOON) prospective longitudinal cohort of over 1500 patients undergoing ACL reconstruction showed no increase in OA symptoms (KOOS subscale) at 2 or 6 years after surgery. Therefore, identification of structural changes of OA that may precede the onset of symptoms is of critical importance for determining risk factors for the initiation and progression of post-traumatic OA in addition to measuring the effectiveness of potential disease-modifying treatments. One structural measure of OA is radiographic joint space width (JSW). We previously demonstrated that meniscus treatment and age predict narrower medial compartment JSW.Methods:335 patients from the MOON cohort (154 males, 181 females, median age 18 years at the time of surgery) were recruited at a minimum of 2 years following surgery for on-site evaluations including bilateral metatarsophalangeal joint (MTP) radiographs to assess JSW. To minimize bias related to pre-existing knee injury or OA, subjects were 35 years or younger, were injured playing a sport, had primary ACL reconstruction without prior meniscus or articular cartilage surgery, did not undergo subsequent ACL revision, and had a surgically normal contralateral knee. Radiographic JSW was measured in the lateral compartment of both knees using a validated semiautomated method. The association of age, sex, BMI, meniscus treatment, and articular cartilage treatment with lateral compartment JSW differences (JSD) between the reconstructed and normal knees was examined using multivariable generalized linear models. The Holm-Bonferroni method was used to account for multiple comparisons.Results:The mean lateral compartment JSW was 7.73 mm and (95% CI 7.61-7.85 mm) for ACL reconstructed knees and 7.82 mm (95% CI 7.71-7.94 mm) for contralateral normal knees, with a mean JSD of 0.10 mm (p<0.01). A miltivariable generalized linear model was constructed which adjusted for age, gender, BMI, and baseline Marx activity level. Predictors of JSD that were statistically significant and predicted narrower JSW on the ACL reconstructed side included partial lateral meniscectomy (p<0.001), Marx activity level less than 16(p=0.002), and higer BMI (p=0.02). Graft source, cartilage injury, sex and lateral compartment articular carilage injury wer not significant. Model results are shown in the table.Conclusion:We found that radiographic lateral compartment JSW differences between reconstructed and normal knees could be detected 2 years after durgery in a cohort of patients with previously uninjured knees who sustained ACL tears and underwent subsequent ACL reconstruction. The model showed that parial lateral meniscectomy, lower Marx activity level, and higher BMI were associated with decreased joint space width. The reason that patients with lower activity levels at baseline have narrower lateral compartment JSW on their ACL reconstructed side is unclear and warrants further study.

A new quantitative measure for radiologic osteoarthritis of the lateral knee compartment distinguishes patients with longstanding lateral meniscectomy from non-pathological knees.

Common radiologic scores to evaluate knee osteoarthritis (OA) have been widely used but are descriptive and may lack objectivity. The aim of this study was to develop a quantitative and objective radiologic measure for the evaluation of lateral knee compartment OA. Furthermore, we tested the reliability of this new measure and its correlation to well-accepted radiologic scores. This retrospective study was performed within the context of a multi-centre long-term follow-up (15-25years) of a patient cohort after partial or total lateral meniscectomy (n=36 knees). In addition, 99 radiographs of clinically and radiologically normal knees were obtained from a control group. Anteroposterior weight-bearing views (0°) and Schuss (45°) views were analysed. The joint height of the lateral knee compartment was measured on the lateral border (lateral joint space height) and in the centre (central joint space height, CJSH) and normalized with respect to the width of the lateral compartment (X). All measurements were taken independently by two observers, allowing for inter- and intra-observer reliability assessments. The results of the two groups were compared using an analysis of covariance. Finally, the correlations between the results and the Fairbank and Kellgren & Lawrence scores were determined using a Spearman ρ rank order correlation. The normalized joint space height in the centre of the compartment on the Schuss view (CJSH/X) showed the highest intra- (ICC=0.980) and inter-observer reliability (ICC=0.982). There was a significant difference in CJSH/X between the control (0.19±0.05) and the meniscectomized knees (0.08±0.07) (p<0.001). CJSH/X showed a significant decline of 11% per 10years in the meniscectomy group. A negative correlation could be found between CJSH/X and the Fairbank (ρ=-0.751; p<0.001) and Kellgren & Lawrence scores (ρ=-0.712; p<0.001). A cut-off value of 0.14 of CJSH/X was defined-representing one standard deviation below the mean of the control group-from which measurements were considered as pathologic. The normalized joint space height measured in the centre of the lateral knee compartment from a Schuss view, CJSH/X, was highly reproducible and showed a significant correlation to established radiologic scores. This new measure has the advantage of being objective and dimensionless and thus independent of the size of the radiograph. The normative values provided by our healthy control knees are useful to help establish an early diagnosis of radiologic lateral knee compartment OA. Retrospective diagnostic study, Level III.

MR T1ρ and T2 of meniscus six months and one year after acute anterior cruciate ligament injury

s / Osteoarthritis and Cartilage 23 (2015) A82eA416 A223 354 MR T1r AND T2 OF MENISCUS SIX MONTHS AND ONE YEAR AFTER ACUTE ANTERIOR CRUCIATE LIGAMENT INJURY A. Wang, F. Su, V. Pedoia, M. Kretzschmar, L. Nardo, T.M. Link, C.B. Ma, X. Li. Univ. of California, San Francisco, San Francisco, CA, USA Purpose: Acute anterior cruciate ligament (ACL) injury, a high-risk factor for post-traumatic osteoarthritis, is often concomitant with meniscal lesions and tears. In our previous cross-sectional study, we found that acute ACL injuries were associated with significantly elevated meniscal T1r and T2 values compared to healthy knees, even in menisci without morphological signs of damage. The goal of this longitudinal study was to evaluate intermediate-term changes in meniscal T1r and T2 quantification in ACL-injured patients six months and one year after ACL reconstruction and to compare these changes to baseline results. Methods: Using a 3T MR scanner, a closed cohort of 39 patients (age 1⁄4 29.4 ± 7.5 years; 16 females) with acute ACL injuries was scanned at an average of 8.4 ± 6.4 weeks post-injury and prior to ACL reconstruction. After ACL reconstruction, follow-up scans of ACL-injured knees were completed at six months and one year after baseline scan. Subjects were categorized by no lateral meniscectomy (n 1⁄4 32) and partial lateral meniscectomy (n 1⁄4 7). Effects of medial meniscectomy were not evaluated due to small sample size (n 1⁄4 2). Imaging protocol included sagittal T2-weighted 3D fast spin-echo (CUBE) images [repetition time (TR)/echo time (TE) 1⁄4 1500/25 ms, field of view (FOV)1⁄4 16 cm, matrix1⁄4 384 x 384, slice thickness1⁄4 1mm, echo train length 1⁄4 50, bandwidth 1⁄4 50 kHz, number of excitations 1⁄4 0.5] and sagittal 3D T1r and T2 quantification sequences [TR/TE 1⁄4 9 ms/min full, FOV1⁄4 14 cm, matrix1⁄4 256 x 128, slice thickness1⁄4 4mm, Views Per Segment 1⁄4 64, time of recovery 1⁄4 1.2 s, spin-lock frequency 1⁄4 500 Hz, ARC phase AF1⁄4 2. TSL1⁄4 0/10/40/80 ms for T1r, and preparation TE1⁄4 0/ 13.7/27.3/54.7 ms for T2]. Menisci were segmented using CUBE images into four sub-compartments: anterior horn of the lateral/medial meniscus (AHLAT/AHMED) and the posterior horn of the lateral/medial meniscus (PHLAT/PHMED). These regions of interest (ROI) were overlaid onto T1r and T2 maps, andmean T1r and T2 values were calculated for each ROI. Paired t-tests were performed when comparing the same cohort at different time points, and unpaired t-tests were performed when comparing patients who had a partial meniscectomy and patients who did not have a meniscectomy. An alpha of less than 0.05 was considered significant. Results: In ACL-injured knees without meniscectomy, T1r values increased significantly from baseline to six months in the AHLAT, AHMED, and PHMED (all p r > -0.46; p r > -0.30; p<0.005). Intraclass correlation coefficients ranged between 0.95-1.00 for the DCE-MRI variables and 0.80-1.00 for the static MRI variables. Conclusions: The results confirm an association between pain and synovitis assessed on both DCEand CE-MRI in obese patients with knee OA. The whole-knee synovitis score on CE-MRI and most of the DCE-MRI variables were also significantly associated with the remaining KOOS items. DCE-MRI analyses were robust and highly reproducible and have the potential to be used to further investigate the role of inflammation and perfusion in knee OA, in a similar way it has been used in inflammatory joint diseases.

Financial impact of third-party reimbursement due to changes in the definition of ICD-9 arthroscopy codes 29880, 29881, and 29877.

The relative value units (RVUs) of the International Classification of Diseases, Ninth Revision (ICD-9) codes 29880 (partial medial and lateral meniscectomy) and 29881 (partial medial or lateral meniscectomy) were decreased from 2011 to 2012, and codes 29877 (debridement or shaving articular cartilage) and G0289 (debridement of articular cartilage or removal of foreign/loose body in a separate compartment) were bundled with codes 29880 and 29881. Our goal was to quantify the decrease in physician reimbursement in 2012 and to determine if there was an increase in the use of codes 29875 (limited synovectomy), 29876 (major synovectomy), and 29879 (abrasion arthroplasty or microfracture). We analyzed a structured query language database for ICD-9 coding and third-party reimbursement of a large group practice. All knee arthroscopy cases were identified, and codes 29880, 29881, and 29877 were specifically assessed and compared between the years 2011 and 2012. The data were analyzed for number of cases, changes in code utilization, reimbursement per individual code and combinations of codes, and change in Medicare reimbursement between years. Statistical analyses were performed with chi-square tests to determine the difference in cases per year, and independent t tests were used to evaluate differences in reimbursement rates by insurance provider per year. Mean surgeon third-party reimbursement for code 29880 decreased from $734.33 in 2011 to $630.40 in 2012 and from $709.17 to $639.18 for code 29881. Comparing the combination of codes 29880/29877 in 2011 to 29880 in 2012, mean reimbursement decreased from $995.07 to $630.40 (-36.65%, p < 0.001); 29881/29877 in 2011 to 29881 in 2012 (-37.39%, p < 0.001) had a similar decrease. Mean Medicare reimbursement decreased from $749.58 for 29880/29877 in 2011 to $532.71 for 29880 in 2012 and from $704.11 for 29881/29877 in 2011 to $527.04 for 29881 in 2012. When referenced to the total number of knee arthroscopy cases each year, overall use of code 29877 decreased from 2710 times in 2011 to 348 times in 2012 (-28.12%). In 2012, the use of code 29875 increased from 247 to 467 times (5.25%), the use of code 29876 increased from 852 to 874 times (4.88%), and the use of code 29879 increased from 119 to 143 times (1.06%). Third-party reimbursement rates for cases in 2011 dropped by over 35% for similar cases in 2012. The percentage drop in Medicare payment has been similar to other payers, but the absolute reimbursements are lower. Codes 29875, 29876, and 29879 were used more often in 2012, but the absolute numbers do not balance the decrease in use of code 29877.

Clinical and radiographic results of arthroscopic partial lateral meniscectomies in stable knees with a minimum follow up of 20 years.

The purpose of this retrospective multicentric study was to evaluate the long-term effects of lateral meniscectomy and to identify those patients who are at the most risk of developing osteoarthritis (OA). Eighty-nine arthroscopic partial lateral meniscectomies in stable knees with a mean follow-up of 22 ± 3 years were included. The following influencing factors were analyzed: age, sex, body mass index (BMI), physical activity, alignment, the types of meniscal lesions, the extent of meniscal resections and the initially associated cartilage lesions. An independent examiner reviewed all patients, using subjective (KOOS and IKDC scores) and objective clinical and radiological evaluations (IKDC score). The contralateral knee was used as a reference to calculate the prevalence and the incidence of OA. The mean age at the time of surgery was 35 ± 13 years. The main location of the lesions was the mid-section of the lateral meniscus (79% of the cases). At the latest follow-up, 48% of the patients had an active lifestyle with as many as 48% of the patients enjoying moderate to intense physical activity 22 years after the procedure (vs. 71% before surgery). The KOOS score evolved from 82 to 69% during the same period. The prevalence of OA was 56% in the affected knee and the difference of prevalence between the operated and healthy knees was 44%. In those patients presenting with an OA of the operated knee and a normal contralateral knee, the incidence of OA was 53%. Predictors of OA were an age superior to 38 years at the time of surgery, obesity (BMI >30), and valgus malalignment as well as the presence of cartilage and degenerative meniscal lesions at the time of surgery. In the long term, arthroscopic partial lateral meniscectomy in stable knees without initial cartilage lesions might yield good to excellent results in young patients. Patients are at higher risk to develop symptomatic OA if they are over 40, having a high BMI, valgus malalignment and cartilage lesions at the time of surgery. This study provides precise guidelines for the surgical treatment of lateral meniscus tears. IV.

Return to Play After Lateral Meniscectomy Compared With Medial Meniscectomy in Elite Professional Soccer Players

Background: Meniscectomy is frequently performed in elite soccer athletes to allow return to a high level of performance as early as possible. Although lateral meniscectomy is known to have more serious long-term sequelae than medial meniscectomy, little is known about the effect of lateral meniscectomy on the time to return to play during the early recovery phase in professional soccer players. Hypothesis: Lateral meniscectomy results in longer times to return to preinjury level of competition and a higher incidence of adverse outcomes compared with medial meniscectomy in elite professional soccer players. Study Design: Cohort study; Level of evidence, 3. Methods: A single-surgeon database containing the injury history and operative details of elite soccer athletes from 2005 to 2009 was used to identify players who had undergone an isolated partial lateral or medial meniscectomy. The time to return to preinjury level of competition, the incidence of adverse events during early recovery, and the need for further arthroscopy were recorded. Time to return to play was analyzed by using the Kaplan-Meier method. A multivariate analysis was used to control for age, location of meniscectomy, percentage of meniscus excised, and type of tear. Results: Ninety soccer players were identified, of which 42 had a lateral meniscectomy and 48 had a medial meniscectomy. The median time to return to play, to the nearest week, was longer in the lateral group than the medial group (7 vs 5; P < .001). At all time points after surgery, the cumulative probability of returning to play was 5.99 times greater (95% confidence interval, 3.34-10.74; P < .001) after medial meniscectomy. More lateral meniscectomy cases experienced adverse events related to pain/swelling—29 (69%) vs 4 (8%) (P < .001)—and required a second arthroscopy: 3 (7%) vs 0 (P = .098). Conclusion: The time to return to preinjury level of competition is significantly longer after lateral than medial meniscectomy in elite professional soccer athletes. Lateral meniscectomy has a higher incidence of adverse events in the early recovery period, including pain/swelling and the need for further arthroscopy. It is also associated with a significantly lower rate of return to play. These findings form the basis of an important discussion that must be had with player and club before a lateral meniscectomy is performed in elite soccer athletes.

Return to Play After Partial Lateral Meniscectomy in National Football League Athletes

Background: Lateral meniscal injury is a common and possibly career-threatening injury among players in the National Football League (NFL). The rate of return to play (RTP) and factors that affect RTP after lateral meniscal injury in NFL players are currently not defined. Purpose: The aims of this study were to determine the rate of RTP to regular-season NFL game play of NFL players after arthroscopic partial lateral meniscectomy and to identify factors that can predict the ability to return to play. Study Design: Case series; Level of evidence, 4. Methods: Seventy-two patients undergoing 77 arthroscopic lateral partial meniscectomies were followed to determine the rate of RTP (defined as successful RTP in at least 1 regular-season NFL game after meniscectomy) and factors predicting players’ ability to return to play. Perioperative variables were recorded using retrospective chart review. Players’ heights and weights, dates of return, draft rounds, and counts of games, starts, and seasons both before and after meniscectomy were all collected from statistical databases maintained by the NFL. Chi-square and Student t tests were performed to assess differences among covariates with respect to an athlete’s ability to return to play, and odds ratios were calculated as appropriate. All percentages were calculated as percent of total procedures performed (n = 77). Results: Of the 77 partial lateral meniscectomies performed, 61% (n = 47) resulted in the athlete returning to play at his previous level of competition with an average length of time to RTP of 8.5 months; 19 (40%) of those who returned were still active in the NFL at the time of follow-up. Age at time of surgery, games and seasons played before surgery, and individual position were not significantly different between those who did and did not return to play. Undergoing a concomitant procedure did not affect an athlete’s ability to return to play, nor did concurrent arthroscopic anterior cruciate ligament reconstruction affect a player’s likelihood to return to play. Players drafted in the first 4 rounds of the NFL draft were 3.7 times more likely to return to play than players drafted after the fourth round, and players who started more than 46.2% of their games played (the mean value for this population) were 2.8 times more likely to return to play. Speed-position players (running backs, receivers, linebackers, and defensive backs) were 4.0 times less likely to return to play than non–speed position players (linemen and tight ends). Conclusion: The majority of NFL players undergoing arthroscopic lateral meniscectomy are able to return to play. Players selected earlier in the NFL draft and who are listed as starters in more of their games are more likely to return to play, as are linemen and tight ends. It is significantly more difficult for running backs, receivers, linebackers, and defensive backs to return to play.

Altered Tibiofemoral Contact Mechanics Due to Lateral Meniscus Posterior Horn Root Avulsions and Radial Tears Can Be Restored with in Situ Pull-Out Suture Repairs

An avulsion of the posterior root attachment of the lateral meniscus or a radial tear close to the root attachment can lead to degenerative knee arthritis. Although the biomechanical effects of comparable injuries involving the medial meniscus have been studied, we are aware of no such study involving the lateral meniscus. We hypothesized that in situ pull-out suture repair of lateral meniscus root avulsions and of complete radial tears 3 and 6 mm from the root attachment would increase the contact area and decrease mean and peak tibiofemoral contact pressures, at all knee flexion angles, relative to the corresponding avulsion or tear condition. Eight human cadaveric knees underwent biomechanical testing. Eight lateral meniscus conditions (intact, footprint tear, root avulsion, root avulsion repair, radial tears at 3 and 6 mm from the posterior root, and repairs of the 3 and 6-mm tears) were tested at five different flexion angles (0°, 30°, 45°, 60°, and 90°) under a compressive 1000-N load. Avulsion of the posterior root of the lateral meniscus or an adjacent radial tear resulted in significantly decreased contact area and increased mean and peak contact pressures in the lateral compartment, relative to the intact condition, in all cases except the root avulsion condition at 0° of flexion. In situ pull-out suture repair of the root avulsion or radial tear significantly reduced mean contact pressures, relative to the corresponding avulsion or tear condition, when the results for each condition were pooled across all flexion angles. Posterior horn root avulsions and radial tears adjacent to the root attachment of the lateral meniscus significantly increased contact pressures in the lateral compartment. In situ pull-out suture repairs of these tears significantly improved lateral compartment joint contact pressures. In situ repair may be an effective treatment to improve tibiofemoral contact profiles after an avulsion of the posterior root of the lateral meniscus or a complete radial tear adjacent to the root. In situ repairs should be further investigated clinically as an alternative to partial lateral meniscectomy.