Alteration in ACL loading after total and partial medial meniscectomy.

Anterior cruciate ligament (ACL) injuries are often caused by high impact loadings during competitive sports but may also happen during regular daily activities due to tissue degeneration or altered mechanics after a previous knee injury or surgery such as meniscectomy. Most existing research on ACL injury has focused on impact loading scenarios or the consequence of ACL injury on meniscus. The objective of the present study was to investigate the effects of varying degrees of medial meniscectomy on the mechanics of intact ACL by performing a poromechanical finite element analysis under moderate creep loadings. Four clinical scenarios with 25%, 50%, 75% and total medial meniscectomy were compared with the intact knee finite element model. Our results suggested that different medial meniscal resections may increase, at different extents, the knee laxity and peak tensile stress in the ACL, potentially leading to collagen fiber fatigue tearing and altered mechanobiology under normal joint loadings. Interestingly, the ACL stress actually increased during early knee creep (~ 3 min) before it reached an equilibrium. In addition, meniscectomy accelerated ACL stress reduction during knee creep, transferred more loading to tibial cartilage, increased contact pressure, and shifted the contact center posteriorly. This study may contribute to a better understanding of the interaction of meniscectomy and ACL integrity during daily loadings.

Editorial Commentary: Complications After Meniscal Surgery Are Rare and Generally Associated With Medical Comorbidity.

Meniscal tears are prevalent and frequently require surgical intervention. This injury affects younger, active patients after acute trauma. Meniscal repair is often indicated. Degenerative tears are more common in elderly patients and are generally treated with partial meniscectomy. Other factors such as chronicity, stability, tear type, and associated injuries may also play a role in the treatment algorithm. In terms of complications, both procedures are generally safe, with a complication rate approximating 1%, but adverse effects such as deep venous thrombosis, pulmonary embolism, surgical-site infection, readmission, and reoperation can occur. Complications are more common in elderly patients. Moreover, recent research shows that complications are associated with medical comorbidities, with smoking, and with longer operating times.

Arthroscopy with partial meniscectomy for degenerative tear does not increase the risk of total knee arthroplasty at five year follow up; however, this population undergoes total knee arthroplasty with a lower threshold of osteoarthritis.

PURPOSE: Degenerative meniscus tears can cause discomfort in some patients, and when medical treatments fail to provide relief, arthroscopy may be considered before resorting to knee prosthesis. However, the benefits of arthroscopy over nonsurgical treatments in patients over 60 years old are limited, and the evidence regarding its overall efficiency and drawbacks remains scarce. Furthermore, there has been no investigation into whether those patients treated with partial meniscectomy, undergo the knee operation at an earlier stage of osteoarthritis. METHODS: This study focused on data from a single Belgian hospital, involving patients over 60 years old with internal meniscal tears. The participants were categorized into two groups based on the treatment they received: arthroscopic partial meniscectomy (APM) or conservative management. The primary outcome assessed was the occurrence of knee arthroplasty within a five year period. Secondary outcomes included evaluating the ICRS cartilage grade and the time taken until total knee arthroplasty (TKA). RESULTS: A total of 194 patients with internal meniscal tears were included in the study. At the 5-year mark, the overall rate of knee arthroplasty was found to be 16.5%, with 11.9% of cases occurring within two years. After the 5-year follow-up, it was observed that 19.2% (24 patients) of the APM group and 11.6% (8 patients) of the conservative management group underwent knee arthroplasty. Notably, patients over 70 years old who underwent APM had a higher risk of eventually requiring TKA compared to those who received conservative management. Additionally, patients who underwent meniscectomy and later underwent TKA showed less wear in the internal compartment of the knee compared to patients in the conservative treatment group who underwent TKA. CONCLUSION: The study suggests that patients who underwent arthroscopy faced a similar risk of knee arthroplasty compared to those who underwent conservative management, excepted for patients over 70 years old. Despite this similar risk of arthroplasty for the whole population, they exhibited lower osteoarthritis severity when compared to the conservative group.

The value of reducing arthroscopic partial meniscectomy in the treatment of degenerative meniscus tears: a budget impact analysis.

AIMS: Numerous studies have shown that arthroscopic partial meniscectomy (APM) is not (cost-) effective in patients with symptoms attributed to a degenerative meniscus tear. We aimed to assess the budget impact of reducing APM in routine clinical practice in this population. MATERIALS AND METHODS: A patient-level state transition model was developed to simulate patients recently diagnosed with a degenerative meniscus tear. Three strategies were compared: "current guideline" (i.e., postpone surgery to at least 3 months after diagnosis), "APM at any time" (i.e., APM available directly after diagnosis), and "nonsurgical" (i.e., APM no longer performed). Total societal costs over 5 years were calculated to determine the budget impact. Probabilistic and deterministic sensitivity analyses were conducted to address uncertainty. RESULTS: The average cost per patient over 5 years were EUR 5,077, EUR 4,577, and EUR 4,218, for the "APM at any time," "current guideline," and "nonsurgical" strategy, respectively. Removing APM from the treatment mix (i.e., 30,000 patients per year) in the Netherlands, resulted in a reduction in health care expenditures of EUR 54 million (95 percent confidence interval [CI] EUR 38 million-EUR 70 million) compared to the "current guideline strategy" and EUR 129 million (95 percent CI EUR 102 million-EUR 156 million) compared to the "APM at any time" strategy. Sensitivity analyses showed that uncertainty did not alter our conclusions. CONCLUSIONS: Substantial costs can be saved when APM is no longer performed to treat symptoms attributed to degenerative meniscus tears in the Netherlands. It is therefore recommended to further reduce the use of APM to treat degenerative meniscus tears.

Finite element analysis of the knee joint stress after partial meniscectomy for meniscus horizontal cleavage tears.

OBJECTIVE: To establish a finite element model of meniscus horizontal cleavage and partial resection, to simulate the mechanical changes of knee joint under 4 flexion angles, and to explore what is the optimal surgical plan. METHODS: We used Mimics Research, Geomagic Wrap, and SolidWorks computer software to reconstruct the 3D model of the knee joint, and then produced the horizontal cleavage tears model of the internal and lateral meniscus, the suture model, and the partial meniscectomy model. These models were assembled into a complete knee joint in SolidWorks software, and corresponding loads and boundary constraints were added to these models in ANSYS software to simulate the changing trend of pressure and shear force on femoral condylar cartilage, meniscus, and tibial cartilage under the flexion angles of 0°, 10°, 20°, 30° and 40° of the knee joint. At the same time, the difference of force area between medial interventricular and lateral interventricular of knee joint under four states of bending the knee was compared, to explore the different effects of different surgical methods on knee joint after horizontal meniscus tear. RESULTS: Within the four medial meniscus injury models, the lowest peak internal pressure and shear force of the knee joint was observed in the meniscal suture model; the highest values were found in the bilateral leaflet resection model and the inferior leaflet resection model; the changes of pressure, shear force and stress area in the superior leaflet resection model were the most similar to the changes of the knee model with the meniscal suture model. CONCLUSION: Suture repair is the best way to maintain the force relationship in the knee joint. However, resection of the superior leaflet of the meniscus is also a reliable choice when suture repair is difficult.

Total Knee Replacement After Arthroscopic Meniscectomy in Knee Osteoarthritis: A Nationwide Population-Based Cohort Study.

BACKGROUND: Recent studies raise concerns that arthroscopic meniscectomy (AM) for degenerative tear may be detrimental to the maintenance of the joint structure. This study was performed to examine the rate of total knee replacement (TKR) among patients with knee osteoarthritis (OA) who underwent AM for meniscal tears and compare this rate with those who did not. METHODS: A retrospective cohort study was conducted using the National Health Insurance Database of South Korea. Among knee OA patients aged 50-79, those who were treated with AM due to meniscal damage from 2007 to 2009 were selected as the AM group while those not treated with AM despite the presence of meniscal damage were selected as control group. Both were matched based on a propensity score and followed-up until the earliest occurrence of: TKR, death, or 10 years. Cox proportional hazards models were used to compare the outcome. RESULTS: A total of 36,974 patients were included in AM groups and non-AM group after 1:1 matching. TKR occurred in 9.62% and 7.64% in AM and non-AM groups with the average duration after meniscectomy of 5.88 ± 2.77 and 5.50 ± 2.94 years, respectively. After adjustment for baseline confounders, the TKR rate in the AM group was calculated to be 25% higher than that in the non-AM group (subdistribution hazard ratio, 1.25; 95% confidence interval, 1.16-1.34). The mortality rate was 5.20%, which did not significantly differ between groups. CONCLUSION: OA patients who underwent AM for the meniscal injury had higher incidence of TKR up to 10 years of follow-up than the non-operated group. The greater TKR utilization observed in patients undergoing AM merits caution when treating OA patients with meniscal injury.

Low early complication rates after arthroscopic meniscus repair and meniscectomy.

PURPOSE: To evaluate the 30-day complication rates after arthroscopic meniscus repair and meniscectomy using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database, with subgroup analysis of patients aged > 40 years. METHODS: NSQIP registries between 2006 and 2019 were queried using Current Procedural Terminology codes to identify patients undergoing arthroscopic meniscus repair (CPT 29882, 29883) and meniscectomy (29880, 29881). The following 30-day complications were assessed: pulmonary embolism (PE), venous thromboembolism (VTE), surgical site infection (SSI), reoperation, and readmission. Complications rates between treatment groups were compared using multivariate logistic regression analyses adjusted for sex, age, steroid use, and smoking/dyspnoea/COPD. A subgroup analysis was performed for patients aged > 40 years. RESULTS: A total 6354 meniscus repairs and 99,372 meniscectomies were identified. Complication rates were < 1% for both meniscus repair and meniscectomy. Meniscus repair was associated with significantly higher rates of PE, VTE, and readmission compared to meniscectomy: PE (0.2% vs 0.1%, p < 0.001), VTE (0.8% vs 0.4%, p < 0.001), superficial SSI (0.1% vs 0.2%, n.s), deep SSI (0.07% vs 0.1%, n.s), reoperation (0.5% vs 0.4%, n.s), and readmission (0.9% vs 0.8%, p = 0.003). Among patients aged > 40 years, complication rates were < 1.3% for both meniscus repair and meniscectomy. Similar trends and rates were found in patients aged > 40 years undergoing meniscus repair versus meniscectomy: PE (0.38% vs 0.12%, p < 0.001), VTE (1.07% vs 0.46%, p < 0.001), superficial SSI (0.03% vs 0.19%, n.s), deep SSI (0.1% vs 0.06%, n.s), reoperation (0.48% vs 0.43%, n.s), and readmission (1.2% vs 0.85%, p = 0.01). CONCLUSION: Arthroscopic meniscus repair and meniscectomy are both low-risk procedures with 30-day complication rates < 1% overall and < 1.3% among patients aged > 40 years. These findings support meniscus repair whenever feasible in the setting of preserved articular cartilage. Understanding of the short-term complication rates after arthroscopic meniscus repair and meniscectomy can aid surgeons in providing comprehensive preoperative counselling to patients considering such treatments, specifically when discussing the risks and benefits of meniscus repair. LEVEL OF EVIDENCE: III.

Ipsilateral chondral lesions worsen the long-term prognosis following arthroscopic partial medial meniscectomy.

PURPOSE: The effect of knee cartilage defects that are detected during partial meniscectomy remains controversial in terms of the long-term prognosis on knee function. This study aimed to investigate the effect of concurrent medial compartment focal cartilage lesions on the long-term prognosis of knee function in patients who underwent arthroscopic partial medial meniscectomy for traumatic medial meniscal tears. METHODS: This retrospective study analyzed 46 patients who underwent arthroscopic partial medial meniscectomy between 1991 and 2008 by a single surgeon. Twenty-one patients who underwent arthroscopic partial medial meniscectomy due to traumatic meniscal tear had focal chondral lesions only at the medial compartment, and these patients were assigned to group A. Twenty-five patients who had no cartilage lesions in any compartments were assigned to group B. The age, sex, body mass index (BMI), follow-up time, age at the time of surgery, clinical and radiological scores, and perioperative arthroscopy findings were analyzed. RESULTS: The mean follow-up time was 20 ± 3.7 years. No significant difference was found in the demographic data, and the average age of the patients at the time of operation was 35 ± 9.5 years. Both groups had improved Lysholm score at the last follow-up. Although no difference was found between the groups during the preoperative period, group B had a higher Lysholm score at the last follow-up than group A. The mean International Knee Documentation Committee (IKDC) and Knee injury and Osteoarthritis Outcome Score (KOOS) scores at the last follow-up were significantly higher in group B. The mean Kellgren-Lawrence grades in the operated knees of group A were higher than those of group B. In group A, a negative correlation was found between the BMI and postoperative Lysholm (r = - 0.461, p = 0.03) IKDC (r = - 0.433, p = 0.05) and KOOS (r = - 0.565, p = 0.008) scores. In group B, no correlation was found between BMI and any score. CONCLUSION: Among patients who underwent arthroscopic partial medial meniscectomy with an average follow-up of 20 years, those with concurrent focal cartilage defect in the medial compartment had clinically and radiologically worse outcomes than patients without any cartilage defect. Therefore, orthopedic surgeons should be meticulous before performing any arthroscopic partial medial meniscectomy in case of concurrent cartilage lesion. LEVEL OF EVIDENCE: Level III.

Medial meniscus posterior root tears and partial meniscectomy significantly increase stress in the knee joint during dynamic gait.

PURPOSE: As a simple and invasive treatment, arthroscopic medial meniscal posterior horn resections (MMPHRs) can relieve the obstructive symptoms of medial meniscus posterior root tears (MMPRTs) but with the risk of aggravating biomechanical changes of the joint. The aim of this study was to analyze dynamic simulation of the knee joint after medial meniscus posterior root tear and posterior horn resection. METHODS: This study established static and dynamic models of MMPRTs and MMPHRs on the basis of the intact medial meniscus model (IMM). In the finite element analysis, the three models were subjected to 1000 N axial static load and the human walking gait load defined by the ISO14243-1 standard to evaluate the influence of MMPRTs and MMPHRs on knee joint mechanics during static standing and dynamic walking. RESULTS: In the static state, the load ratio of the medial and lateral compartments remained nearly constant (2:1), while in the dynamic state, the load ratio varied with the gait cycle. After MMPHRs, at 30% of the gait cycle, compared with the MMPRTs condition, the maximum von Mises stress of the lateral meniscus (LM) and the lateral tibial cartilage (LTC) were increased by 166.0% and 50.0%, respectively, while they changed by less than 5% during static analysis. The maximum von Mises stress of the medial meniscus (MM) decreased by 55.7%, and that of the medial femoral cartilage (MFC) increased by 53.5%. CONCLUSION: After MMPHRs, compared with MMPRTs, there was no significant stress increase in articular cartilage in static analysis, but there was a stress increase and concentration in both medial and lateral compartments in dynamic analysis, which may aggravate joint degeneration. Therefore, in clinical treatments, restoring the natural structure of MMPRTs is first recommended, especially for physically active patients.

Meniscectomy is associated with a higher rate of osteoarthritis compared to meniscal repair following acute tears: a meta-analysis.

PURPOSE: Meniscal tears are common and may impair knee function and biomechanics. This meta-analysis compared meniscal repair versus resection in patients with symptomatic meniscal tears in terms of patient-reported outcomes measures (PROMs), joint width, surgical failure, and rate of progression to osteoarthritis (OA) at conventional radiography. METHODS: This study was conducted according to the 2020 PRISMA statement. In August 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. Two reviewers independently performed the analysis and a methodological quality assessment of the included studies. All the clinical investigations which compared repair versus resection of meniscal tears were accessed. RESULTS: Data from 20 studies (31,783 patients) were collected. The mean BMI was 28.28 ± 3.2 kg/m2, and the mean age was 37.6 ± 14.0 years. The mean time elapsed from injury to surgery was 12.1 ± 10.2 months and the mean medial joint width was 4.9 ± 0.8 mm. Between studies comparability at baseline was found in age, women, BMI, time from injury to surgery and length of the follow-up, PROMs, medial joint width, and stage of OA. The resection group demonstrated a greater Lysholm score (P = 0.02). No difference was found in the International Knee Documentation Committee (P = 0.2). Nine studies reported data on the rate of failures at a mean of 63.00 ± 24.7 months. No difference was found between the two groups in terms of persistent meniscal symptoms (P = 0.8). Six studies reported data on the rate of progression to total knee arthroplasty at a mean of 48.0 ± 14.7 months follow-up. The repair group evidenced a lower rate of progression to knee arthroplasty (P = 0.0001). Six studies reported data on the rate of advanced knee OA at a mean of 48.0 ± 14.7 months of follow-up. The repair group evidenced a lower rate of advanced knee OA (P = 0.0001). No difference was found in the mean joint space width (P = 0.09). CONCLUSION: Meniscal repair is associated with a lower progression to knee osteoarthritis at approximately six years of follow-up compared to partial meniscectomy. No difference in PROMs, medial joint width, and failures were evidenced. LEVEL OF EVIDENCE: Level III, meta-analysis.

Prior Meniscectomy in Patients Undergoing Primary Total Knee Arthroplasty is Associated With Worse Short-Term Outcomes.

BACKGROUND: Patients undergoing total knee arthroplasty (TKA) who have prior meniscectomy may have increased rates of postoperative infection, arthrofibrosis, and revision. However, aside from an increased risk of complications, it is unclear whether prior meniscectomy impacts functional outcomes after TKA. This study was conducted to compare functional outcomes following TKA in patients who did and did not have a prior meniscectomy. We hypothesized that patients who had a prior ipsilateral meniscectomy would have worse functional outcomes after undergoing TKA. METHODS: A retrospective matched case-control study was conducted at a tertiary academic center. Patients who underwent both meniscectomy and TKA (cases) or TKA alone (controls) from 2013 to 2020 were identified from our institutional database using current procedural terminology codes. Cases were matched in a 1:3 ratio to controls using age, sex, race, body mass index, and a comorbidity index. Inclusion criteria comprised a minimum of 1-year follow-up for the Knee Injury and Osteoarthritis Outcome Score Junior (KOOS-JR). Exclusion criteria included patients undergoing revision TKA and patients who had a history of ligamentous knee surgery or fracture. T- and Chi-squared analyses were conducted, with significance threshold being P < .05. A total of 589 cases and 1,767 controls were included after matching. There were no significant differences in demographic variables. Cases underwent TKA after their meniscectomy at a mean of 2.9 years (range: 42 days to 16 years). RESULTS: While no significant difference existed for preoperative KOOS-JR scores (46.4 versus 46.4; P = .984), postoperative KOOS-JR scores were significantly lower in the case group (71.9 versus 75.3; P = .001). The case group also achieved the KOOS-JR minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) at significantly lower rates than the control group [(MCID: 71.0 versus 77.3%; P = .011) (PASS: 69.4 versus 76.7%; P = .001);]. CONCLUSION: Patients who had a prior meniscectomy may experience lower postoperative functional outcome scores after TKA and had a lower rate of achieving the MCID and PASS for KOOS-JR. Patient expectations should be adjusted accordingly.

Posterior subtotal meniscectomy revealed the worst scenario for the progression of osteocartilaginous damage in cases of juvenile discoid lateral meniscus with peripheral tear.

INTRODUCTION: We compared subtotal meniscectomy and saucerization with stabilization for osteocartilaginous damage based on injured location and further examined the factors related to osteocartilaginous damage in juvenile discoid lateral meniscus (DLM) with peripheral tear after a follow-up period of at least 5 years. MATERIALS AND METHODS: We retrospectively reviewed juvenile DLM patients with peripheral tear who underwent arthroscopic surgery with more than 5 years of follow-up. Osteocartilaginous damage, which was identified by osteochondritis dissecans (OCD) development and the whole-organ magnetic resonance imaging score (WORMS) of cartilage grade ≥ 3, was compared between subtotal meniscectomy and saucerization with stabilization. A subgroup analysis examining the location of the tear site was performed. Factors for osteocartilaginous damage were analyzed between the damaged and non-damaged groups. RESULTS: Forty-one patients, including 29 who underwent saucerization with stabilization and 12 who underwent subtotal meniscectomy, were included in this study. Seven patients developed OCD lesions; six patients showed cartilage WORMS of more than grade 3. Overall, there was a significant difference in the total cartilage and meniscus WORMS between the two groups at the final follow-up. The subgroup analysis demonstrated more severe osteocartilaginous damage developed in posterior subtotal meniscectomy than in posterior stabilization following saucerization. The damaged group showed significant difference compared to the non-damaged group in terms of age (p = 0.003), sex (p = 0.036), and posterior subtotal meniscectomy (p < 0.001). CONCLUSIONS: Posterior subtotal meniscectomy revealed the worst scenario for the progression of osteocartilaginous damage in cases of juvenile DLM with peripheral tear over a minimum follow-up period of 5 years.

Arthroscopic partial meniscectomy for the degenerative meniscus tear: a comparison of patients included in RCTs and prospective cohort studies.

BACKGROUND AND PURPOSE: Concerns exist regarding the generalizability of results from randomized controlled trials (RCTs) evaluating arthroscopic partial meniscectomy (APM) to treat degenerative meniscus tears. It has been suggested that study populations are not representative of subjects selected for surgery in daily clinical practice. Therefore, we aimed to compare patients included in trials and prospective cohort studies that received APM for a degenerative meniscus tear. PATIENTS AND METHODS: Individual participant data from 4 RCTs and 2 cohort studies undergoing APM were collected. 1,970 patients were analyzed: 605 patients included in RCTs and 1,365 included in the cohorts. We compared patient and disease characteristics, knee pain, overall knee function, and health-related quality of life at baseline between the RCT and cohort groups using standardized differences, ratios comparing the variance of continuous covariates, and graphical methods such as quantile-quantile plots, side-by-side boxplots, and non-parametric density plots. RESULTS: Differences between RCT and the cohort were observed primarily in age (younger patients in the cohort; standardized difference: 0.32) and disease severity, with the RCT group having more severe symptoms (standardized difference: 0.38). While knee pain, overall knee function, and quality of life generally showed minimal differences between the 2 groups, it is noteworthy that the largest observed difference was in knee pain, where the cohort group scored 7 points worse (95% confidence interval 5-9, standardized difference: 0.29). CONCLUSION: Patients in RCTs were largely representative of those in cohort studies regarding baseline scores, though variations in age and disease severity were observed. Younger patients with less severe osteoarthritis were more common in the cohort; however, trial participants still appear to be broadly representative of the target population.

Does anterior cruciate ligament reconstruction increase venous thromboembolism risk compared with knee meniscectomy under arthroscopy?

BACKGROUND: This study compared the incidence of postoperative venous thromboembolism (VTE) between meniscectomy and anterior cruciate ligament reconstruction (ACLR) under arthroscopy and assessed whether ACLR increases the VTE risk compared with meniscectomy. METHODS: A retrospective study of prospectively collected clinical data, including data on 436 patients ranging in age from 18 to 60 years who underwent ACLR or meniscectomy surgery, was performed between October 2018 and October 2019 in our hospital. All patients underwent routine VTE screening by venous ultrasonography in postoperative week 2 and then clinical follow-up at 4 and 6 weeks post-surgery. The incidence of VTE was calculated, and clinical factors such as age, sex, body mass index (BMI), smoking, concomitant procedure, Caprini score, and duration of tourniquet use were evaluated in relation to the risk factors for VTE. RESULTS: A total of 320 patients who underwent arthroscopic ACLR or meniscectomy were available for analysis. Of these patients, 130 (40.6%) underwent ACLR, and 190 (59.4%) underwent meniscectomy. No cases of pulmonary embolism (PE) or femoral deep vein thrombosis (DVT) were reported in either group. Fourteen patients (10.8%) developed VTE in the ACLR group compared with 10 (5.3%) in the meniscectomy group, with no significant difference (p = 0.066). Among these patients, 4 (3.1%) patients in the ACL reconstruction group and 2 (1.1%) patients in the meniscectomy group had DVT confirmed by Doppler ultrasound (p > 0.05). ACLR, age, and BMI (OR = 3.129; 1.061; 1.435) tended to increase the risk of VTE, but the results were not statistically significant (p = 0.056, 0.059, 0.054). CONCLUSIONS: The incidence of VTE after ACLR and meniscectomy within 6 weeks post-surgery was 10.8 and 5.3%, respectively. ACLR, age, and BMI had a tendency to increase the risk of VTE.

The efficacy of intraarticular viscosupplementation after arthroscopic partial meniscectomy: a randomized controlled trial.

BACKGROUND: This study aimed to evaluate the efficacy of viscosupplementation after arthroscopic partial meniscectomy. METHOD: A randomized controlled trial of 47 patients who underwent arthroscopic partial meniscectomy was conducted between March 2020 and March 2021. Patients were randomized into two groups: a viscosupplementation group (n = 23) and a control group (n = 24). A single-dose intraarticular hyaluronic acid injection was used as viscosupplementation. The 100 mm visual analogue scale (VAS) for pain assessment was measured at baseline and at 1 day, 2 weeks, 6 weeks, and 3 months post-surgery. The International Knee Documentation Committee (IKDC), Tegner, Lysholm, and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores and range of motion (ROM) of the knee were measured at baseline, 2 weeks, 6 weeks, and 3 months. RESULTS: The 100 mm VAS score for pain was significantly lower in the viscosupplementation group at 2 weeks post-surgery (27.5 mm vs. 40.7 mm, P = 0.047). ROM was significantly greater in the viscosupplementation group than in the control group at 2 weeks (131.5° vs. 121.0°, P = 0.044) post-surgery. No significant differences were observed in the IKDC or in the Tegner, Lysholm, and WOMAC scores between the two groups. CONCLUSIONS: Viscosupplementation after arthroscopic partial meniscectomy significantly reduced pain at 2 weeks post-surgery and improved ROM of the knee at 2 weeks post-surgery. There might be some benefits in terms of pain and functional recovery of viscosupplementation after arthroscopic surgery. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. TRIAL REGISTRATION: This randomized controlled trial was registered at cris.nih.go.kr # KCT0004921 .

Corticosteroid injections 2 months before arthroscopic meniscectomy increases the rate of postoperative infections requiring surgical irrigation and debridement.

PURPOSE: Consensus guidelines recommend administering a corticosteroid injection (CSI) for patients with a symptomatic degenerative meniscus lesion prior to arthroscopic partial meniscectomy (APM). A recent study found that CSI administered within 1 month prior to meniscectomy is associated with an increased risk of postoperative infection. However, infections may range in severity from superficial infections to serious infections requiring surgical interventions. The aim of this analysis was to define the rate of infections requiring surgery after APM and determine its relationship to preoperative CSI. METHODS: The PearlDiver Mariner administrative claims database was queried for patients > 35 years old who had a CSI in the year prior to isolated APM. Rates of deep infection and infection requiring surgery within 6 months were reported between matched patients with a CSI and no injection. RESULTS: After matching, there were 16,009 patients per group with a mean age of 59.4 years (SD = 9.6), 53.5% obesity, and 40% male. Forty-four of 113 patients who developed a postoperative deep infection went on to have a reoperation for irrigation and/or debridement (0.1% of all APM). Of these 44 patients, 30 had a preoperative CSI and 14 were controls unadjusted odds ratio (unadj-OR) if given CSI = 1.95, 95% CI 1.03-3.68, P = 0.04). Having a CSI within the month before surgery conferred a 4.56-fold increase in odds of an infection warranting surgery (95% CI 1.96-10.21, P < 0.01), whilst having a CSI 4-8 weeks before surgery conferred a 2.42-fold increase in odds (95% CI 1.04-5.42, P = 0.03). Receiving multiple CSI in the year prior to APM was associated with 5.27-fold increased odds of an infection requiring surgery (95% CI 1.19-23.27, P = 0.03), compared to having a single CSI. CONCLUSIONS: Serious infections requiring a surgical intervention are rare after a meniscectomy, occurring in 0.1% of APMs in a matched cohort of patients over 35. Patients were five times more likely to return to the operating room for infection after APM if they had a CSI in the month before or had multiple CSIs in the year before surgery. The risk of infection was no longer significant if there was at least a 2-month interval between preoperative CSI and APM. LEVEL OF EVIDENCE: Level III.

Anterior cruciate ligament reconstruction with lateral plasty restores anterior-posterior laxity in the case of concurrent partial medial meniscectomy.

PURPOSE: To evaluate the in vivo knee laxity in the presence of a partial medial meniscectomy before and after a single-bundle ACL reconstruction with a lateral plasty (SBLP) and to compare it with the knee laxity after a single-bundle ACL reconstruction (SB). METHODS: One-hundred and one patients with ACL tear were enrolled in the study and grouped according to the surgical technique and the meniscus treatment: regarding the SBLP technique (n = 55), 31 patients underwent isolated ACL reconstruction ("SBLP Isolated ACL Group"), while 24 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SBLP ACL + MM Group"); regarding the SB technique (n = 46), 33 patients underwent isolated ACL reconstruction ("SB Isolated ACL Group"), while 13 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SB ACL + MM Group"). Anterior-posterior clinical laxity at 30° (AP30) and 90° (AP90) of knee flexion was quantified before and after surgery through a surgical navigation system dedicated to kinematic assessment. RESULTS: In the ACL-deficient status, the antero-posterior laxity was significantly higher in the presence of a combined MM in both the AP30 and the AP90, with no differences between the two surgical techniques. After the ACL reconstruction, both AP30 and AP90 translations decreased significantly (p < 0.0001) compared to the ACL-deficient status. No differences were found for AP30 and AP90 between SBLP Isolated ACL and SBLP + MM groups, while a significantly higher AP90 translation was found for the SB + MM group compared to the SB Isolated ACL group. Moreover, the AP90 translation in the SB ACL + MM group was significantly higher than the one of the other three groups, i.e., SBLP ACL + MM, SB, and SBLP Isolated ACL group. CONCLUSION: The ACL reconstruction with lateral plasty reduced the AP knee laxity caused by the medial meniscectomy in the context of an ACL surgery. LEVEL OF EVIDENCE: Level II.

Do Synovial Inflammation and Meniscal Degeneration Impact Clinical Outcomes of Patients Undergoing Arthroscopic Partial Meniscectomy? A Histological Study.

The menisci exert a prominent role in joint stabilization and in the distribution of mechanical loading. Meniscal damage is associated with increased risk of knee OA. The aim of this study was to characterize the synovial membrane and meniscal tissues in patients undergoing arthroscopic partial meniscectomy for meniscal tear and to evaluate association with clinical outcomes. A total of 109 patients were recruited. Demographic and clinical data were collected. Visual Analogic Scale (VAS) measuring pain and Knee injury and Osteoarthritis Outcome Score (KOOS) were recorded at baseline and at 2-years follow-up. Histological and immunohistochemical characterizations were performed on synovial membranes and meniscal tissues. More than half of the patients demonstrated synovial mononuclear cell infiltration and hyperplasia. Synovial fibrosis was present in most of the patients; marked vascularity and CD68 positivity were observed. Inflammation had an impact on both pain and knee symptoms. Patients with synovial inflammation had higher values of pre-operative VAS and inflammation. Higher pre-operative pain was observed in patients with meniscal MMP-13 production. In conclusion, multivariate analysis showed that synovial inflammation was associated with pre-operative total KOOS scores, knee symptoms, and pain. Moreover, meniscal MMP-13 expression was found to be associated with pre-operative pain in multivariate analysis. Thus, targeting inflammation of the synovial membrane and meniscus might reduce clinical symptoms and dysfunction at the time of surgery.

Corticosteroid Injections 1 Month Before Arthroscopic Meniscectomy Increase the Risk of Surgical-Site Infection.

PURPOSE: To define the incidence of postoperative infections in patients who receive corticosteroid injections prior to arthroscopic meniscectomy, to determine whether there is a temporal relation between injections and the risk of surgical-site infections, and to identify corresponding risk factors. METHODS: The Humana administrative claims database was reviewed for patients undergoing arthroscopic meniscectomy within 1 year of injection and those undergoing arthroscopic meniscectomy without prior injection. Patients with preoperative injections were further stratified by the duration in months between the injection and the surgical procedure. Surgical-site infection within 6 months of surgery was recorded. Univariate analysis and binary logistic regression were performed to determine independent risk factors for surgical-site infection. Statistical significance was defined as P < .05. RESULTS: We identified patients with (n = 11,652) and without (n = 37,261) a history of a knee corticosteroid injection within 1 year of arthroscopic meniscectomy with at least 6 months of database activity from 2007 to 2017. In patients who received knee injections within 1 month prior to surgery, the rate of development of postoperative infections was twice that in patients who did not receive an injection (1.28% vs 0.63%; odds ratio [OR], 1.84; 95% confidence interval [CI], 1.24-2.62; P = .001). Multivariate logistic regression identified male sex (OR, 1.39; 95% CI, 1.14-1.71; P = .001), diabetes (OR, 1.48; 95% CI, 1.19-1.85; P < .001), chronic obstructive pulmonary disease (OR, 1.57; 95% CI, 1.27-1.94; P < .001), obesity (OR, 1.32; 95% CI, 1.07-1.63; P = .010), tobacco use (OR, 1.61; 95% CI, 1.30-1.98; P < .001), and preoperative injections within 1 month of surgery (OR, 1.78; 95% CI, 1.21-2.54; P = .002) as significant predictors, whereas injections administered more than 1 month before surgery were not significantly associated with postoperative surgical-site infection after arthroscopic meniscectomy. CONCLUSIONS: Injections 1 month before arthroscopic meniscectomy significantly increase the risk of surgical-site infection. However, injections can be safely administered more than 1 month prior to surgery because there is no increased risk of postoperative infection at this time point. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Administrative Databases Used for Sports Medicine Research Demonstrate Significant Differences in Underlying Patient Demographics and Resulting Surgical Trends.

PURPOSE: To discern differences between the PearlDiver and MarketScan databases with regards to patient demographics, costs, reoperations, and complication rates for isolated meniscectomy. METHODS: We queried the PearlDiver Humana Patient Records Database and the IBM MarketScan Commercial Claims and Encounters database for all patients who had record of meniscectomy denoted by Current Procedure Terminology 29880 or 29881 between January 1, 2007, and December 31, 2016. Those that had any other knee procedure at the same time as the meniscectomy were excluded, and the first instance of isolated meniscectomy was recorded. Patient demographics, Charlson Comorbidity Index, reoperations, 30- and 90-day complication rates, and costs were collected from both databases. Pearson's χ2 test with Yate's continuity correction and the Student t test were used to compare the 2 databases, and an alpha value of 0.05 was set as significant. RESULTS: We identified 441,147 patients with isolated meniscectomy from the MarketScan database (0.36% of total database), approximately 10 times the number of patients (n = 49,924; 0.20% of total database) identified from PearlDiver. The PearlDiver population was significantly older (median age: 65-69) than the MarketScan cohort, where all patients were younger than 65 (median age: 52; P < .001). Average Charlson Comorbidity Index was significantly lower for MarketScan (0.172, standard deviation [SD]: 0.546) compared with PearlDiver (1.43, SD: 2.05; P < .001), even when we restricted the PearlDiver cohort to patients younger than 65 years (1.02, SD: 1.74; P < .001). The PearlDiver <65 years subcohort also had increased 30- (relative risk 1.53 [1.40-1.67]) and 90-day (relative risk 1.56 [1.47-1.66]) postoperative complications compared with MarketScan. Overall, laterality coding was more prevalent in the PearlDiver database. CONCLUSIONS: For those undergoing isolated meniscectomy, the MarketScan database comprised an overall larger and younger cohort of patients with fewer comorbidities, even when examining only subjects younger than 65 years of age. LEVEL OF EVIDENCE: Level III, retrospective comparative study.