Lateral Meniscectomy Research Articles

Complications of Arthroscopic Meniscectomy in the Older Population

Background: Complications of arthroscopic meniscectomy in the older population have not been established. Purpose: To determine the risk and relative risk of developing pyogenic arthritis (PA), a deep vein thrombosis (DVT), and pulmonary embolism (PE) in an older population of patients who have undergone arthroscopic meniscectomy. Study Design: Case series; Level of evidence, 4. Methods: Men and women ≥65 years old who underwent procedures coded as CPT-29880 (medial and lateral meniscectomy) and CPT-29881 (medial or lateral meniscectomy) were identified in the Medicare Standard Analytic Files database from 2005 to 2008. Identified patients were analyzed for gender and postoperative complications, including PA, DVT, and PE, occurring within 90 days of the index operation. Results: Overall, 314,578 patients (119,814 men and 194,764 women) were identified. With respect to the Current Procedural Terminology codes, 131,420 patients were coded 29880 and 183,158 patients were coded 29881. In the study population, 0.4% (1107 patients) developed PA, 0.8% (2507 patients) developed a DVT, and 0.3% (982 patients) developed a PE. Among male patients, 0.4% developed PA, 0.7% developed a DVT, and 0.2% developed a PE. Among female patients, 0.3% developed PA, 0.8% developed a DVT, and 0.3% developed a PE. Overall, men had a statistically significant higher relative risk of PA and women had a statistically significant higher relative risk of DVT and PE. Conclusion: Postoperative complications, including PA, DVTs, and PEs, are rare in patients ≥65 years old. However, gender-specific differences in the rate and type of postoperative complications may exist. Further studies in this population are warranted.

Full-Thickness Knee Articular Cartilage Defects in National Football League Combine Athletes Undergoing Magnetic Resonance Imaging: Prevalence, Location, and Association With Previous Surgery

To better define the prevalence and location of full-thickness articular cartilage lesions in elite football players undergoing knee magnetic resonance imaging (MRI) at the National Football League (NFL) Invitational Combine and assess the association of these lesions with previous knee surgery. We performed a retrospective review of all participants in the NFL Combine undergoing a knee MRI scan from 2005 to 2009. Each MRI scan was reviewed for evidence of articular cartilage disease. History of previous knee surgery including anterior cruciate ligament reconstruction, meniscal procedures, and articular cartilage surgery was recorded for each athlete. Knees with a history of previous articular cartilage restoration surgery were excluded from the analysis. A total of 704 knee MRI scans were included in the analysis. Full-thickness articular cartilage lesions were associated with a history of any previous knee surgery (P < .001) and, specifically, previous meniscectomy (P < .001) but not with anterior cruciate ligament reconstruction (P = .7). Full-thickness lesions were present in 27% of knees with a previous meniscectomy compared with 12% of knees without any previous meniscal surgery. Full-thickness lesions in the lateral compartment were associated with previous lateral meniscectomy (P < .001); a similar relation was seen for medial meniscus tears in the medial compartment (P = .01). Full-thickness articular cartilage lesions of the knee were present in 17.3% of elite American football players at the NFL Combine undergoing MRI. The lateral compartment appears to be at greater risk for full-thickness cartilage loss. Previous knee surgery, particularly meniscectomy, is associated with these lesions. Level IV, therapeutic case series.

Partial Meniscectomy Changes Fluid Pressurization in Articular Cartilage in Human Knees

Partial meniscectomy is believed to change the biomechanics of the knee joint through alterations in the contact of articular cartilages and menisci. Although fluid pressure plays an important role in the load support mechanism of the knee, the fluid pressurization in the cartilages and menisci has been ignored in the finite element studies of the mechanics of meniscectomy. In the present study, a 3D fibril-reinforced poromechanical model of the knee joint was used to explore the fluid flow dependent changes in articular cartilage following partial medial and lateral meniscectomies. Six partial longitudinal meniscectomies were considered under relaxation, simple creep, and combined creep loading conditions. In comparison to the intact knee, partial meniscectomy not only caused a substantial increase in the maximum fluid pressure but also shifted the location of this pressure in the femoral cartilage. Furthermore, these changes were positively correlated to the size of meniscal resection. While in the intact joint, the location of the maximum fluid pressure was dependent on the loading conditions, in the meniscectomized joint the location was predominantly determined by the site of meniscal resection. The partial meniscectomy also reduced the rate of the pressure dissipation, resulting in even larger difference between creep and relaxation times as compared to the case of the intact knee. The knee joint became stiffer after meniscectomy because of higher fluid pressure at knee compression followed by slower pressure dissipation. The present study indicated the role of fluid pressurization in the altered mechanics of meniscectomized knees.

Changes of contact pressure and area in patellofemoral joint after different meniscectomies

We investigated the contact pressure and area of the patellofemoral joint both before and after different meniscectomies to provide a biomechanical basis for selecting meniscectomy and its clinical application for meniscus injuries. Six fresh cadaveric knees were used in the study. Using Staubli robots and an ultra-low-min-type pressure-sensitive tablet, changes in contact area and stress in the patellofemoral joint were measured at various flexion angles following different parts and degrees of meniscectomy. The patellofemoral contact area enlarged with the increase of knee flexion angle. From the values obtained from contact areas and average contact pressure of the patellofemoral joint, we found no significant difference between partial meniscectomy and intact knees, but a significant difference was found between total meniscectomy and intact knees. The contact area after lateral meniscectomy was statistically less than that of intact knees. The mean patellofemoral contact pressure after lateral meniscectomy was larger than in intact knees at each angle of flexion. No significant difference in contact area was observed between intact knees and medial meniscectomy. The average patellofemoral contact pressure after medial meniscectomy was larger than in intact knees from 0° ~ 30° of knee flexion, and no significant differences were found between intact knees and medial meniscectomy while knee bending from 60° to 90°. Different meniscectomies result in high contact pressure or disordered distribution of contact pressure, which may be the cause of postoperative patellofemoral degenerative arthrosis.

Inferior Lateral Genicular Artery Injury during Anterior Cruciate Ligament Reconstruction Surgery

We report a case of inferior lateral genicular artery (ILG) injury during anterior cruciate ligament (ACL) reconstruction surgery with lateral partial meniscectomy. This is a rare arthroscopy complication. A review of the literature has been made with the aim to define the anatomy of ILG across the lateral articular line and the risk of lesion during knee arthroscopy. We propose embolization as a good treatment option for this type of injuries.

Dynamic Contact Mechanics of Radial Tears of the Lateral Meniscus: Implications for Treatment

To characterize the effect of radial tears (RTs) of the lateral meniscus and their subsequent treatment (inside-out repair, partial meniscectomy) on joint contact mechanics during simulated gait. Six human cadaveric knees were mounted on a simulator programmed to mimic human gait. A sensor was inserted below the lateral meniscus to measure peak joint contact pressure location, magnitude, and contact area. The following conditions were compared: intact meniscus, 30% RT (at the popliteal hiatus), 60% RT, 90% RT, repair, and partial meniscectomy. Data were analyzed in the midstance phase of gait (14% and 45%) when axial force was at its highest (2,100 N). Intact knees had peak contact pressures of 5.9 ± 0.9 MPa and 6.4 ± 1.1 MPa at 14% and 45% of gait, respectively. RTs of up to and including 60% had no effect on pressure magnitude or location. RTs of 90% resulted in significantly increased peak pressure (8.4 ± 1.1 MPa) in the postero-peripheral aspect of the tibial plateau and reduced contact area versus the intact knee, at 45% of gait. Repair resulted in a significant decrease in peak pressure (7.7 ± 1.0 MPa) relative to 90% RT but had no effect on contact area. Partial lateral meniscectomy resulted in areas and pressures that were not significantly different from 90% tears (8.7 ± 1.5 MPa). Simulated large RTs of the lateral meniscus in the region of the popliteal hiatus show unfavorable dynamic contact mechanics that are not significantly different from those resulting from a partial lateral meniscectomy. Pressure was significantly reduced with inside-out repair but was not affected by partial meniscectomy; contact area was not restored to that of the intact condition for either procedure. Large RTs in the region of the popliteal hiatus show unfavorable dynamic contact mechanics.

Anteromedial versus central single-bundle graft position: which anatomic graft position to choose?

To compare the time-zero stability of an anatomic anteromedial (AM) single-bundle ACL reconstruction to an anatomic central (CTR) single-bundle ACL reconstruction. Twelve (6 paired) hip to knee cadaveric specimens were studied. Using custom ACL computer navigation software, a Lachman test and a previously validated, navigated mechanized pivot shift test were performed on 4 separate experimental groups in each specimen: (1) intact ACL, (2) ACL deficient with total medial and lateral meniscectomy, (3) following anatomic AM single-bundle ACL reconstruction, and (4) after anatomic CTR single-bundle ACL reconstruction. Maximum anterior tibial translation in each group was measured. Lachman: No significant difference was observed between the AM and CTR reconstructions (n.s.) or between reconstruction and the intact ACL (3.4±1.7mm) (n.s.). Pivot Shift: Both the AM and CTR ACL reconstructions significantly reduced anterior translation relative to the ACL/menisci-deficient condition (lateral compartment: 8.9±3.8 mm and 6.75±4.6 mm vs. 17.25±3.5mm, respectively; P<0.001 and medial compartment: -3.0±5.3 mm vs. -3.7±5.7 mm vs. 6.2±6.7mm, P<0.05). There was also a significant difference between the AM (P<0.001) and CTR (P<0.05) ACL reconstructions and the intact ACL (2.8±4.4mm) for lateral compartment translation. Further, no difference was found between lateral or medial compartment translations in the AM versus CTR reconstructions (n.s.). It has been shown that there was no difference in the time-zero biomechanical stability between an anatomic anteromedial and anatomic central single-bundle ACL reconstruction. Given the current debate on the best anatomic ACL reconstruction technique, anatomic socket position in either the anteromedial or central locations provides similar time-zero biomechanics.

Predictors of Radiographic Knee Osteoarthritis After Anterior Cruciate Ligament Reconstruction

Background: Evidence suggests that single-bundle anterior cruciate ligament (ACL) reconstruction does not reliably prevent the development of knee osteoarthritis (OA). Purpose: This study was conducted to determine the overall prevalence of and risk factors for the development of radiographic knee OA after single-bundle ACL reconstruction. Study Design: Case control study; Level of evidence, 3. Methods: There were 249 individuals who had undergone primary single-bundle ACL reconstruction included in this retrospective cohort study. Follow-up radiographs were scored by a single orthopaedic surgery sports medicine fellow using the Kellgren-Lawrence (KL) scale to determine the degree of OA in the medial, lateral, and patellofemoral compartments. Radiographic OA of the involved knee was considered to be present if, compared with the noninvolved knee, there was at least a 2-grade difference in the KL score in at least 1 compartment or a 1-grade difference in at least 2 compartments. Predictors of OA that were explored included patient age, sex, body mass index (BMI), smoking status activity level, meniscectomy before or concurrent with ACL reconstruction, chondral injury present at the time of ACL reconstruction, graft type and source, tibial and femoral tunnel positions, need for revision, and length of follow-up. Univariable and stepwise multivariable logistic regressions were used to identify factors that were associated with radiographic knee OA. Results: Thirty-nine percent of the patients had radiographic OA an average of 7.8 years after surgery. Female sex, BMI, time from injury to surgery, medial and patellofemoral compartment chondrosis, prior medial or lateral meniscectomy, concurrent medial meniscectomy, and length of follow-up were associated with radiographic knee OA after ACL surgery. Stepwise multivariable logistic regression indicated that prior medial meniscectomy (95% confidence interval [CI], 1.39-6.85), grade 2 or greater medial chondrosis (95% CI, 1.27-6.73), length of follow-up (95% CI, 1.07-1.24), and BMI (overweight 95% CI, 1.08-3.84; obese 95% CI, 1.34-7.80) were the best set of predictors of knee OA. Conclusion: Despite reduced laxity and instability and improved activity and participation, individuals who have undergone ACL reconstruction are still at high risk for developing knee OA compared with the general population. The strongest predictors of knee OA after ACL reconstruction were obesity and grade 2 or greater chondrosis in the medial compartment. These results may aid in identifying patients at risk for OA after ACL reconstruction.

Expression of β-defensin-4 in “an in vivo and ex vivo model” of human osteoarthritic knee meniscus

To investigate, for the first time, the expression of β-defensins-4, by immunohistochemistry and western blotting, in OA meniscus versus control meniscus, thus providing new insights into the physiological processes of meniscus repairing. β-defensins-4 was studied in vivo, in knee osteoarthritic menisci obtained from 30 patients (20 men and 10 women) who underwent isolated arthroscopic partial medial or lateral meniscectomy, and in vitro on fibrochondrocyte cells from human OA knee menisci. The study was conducted using morphological, immunohistochemical, and Western blot analysis. The histological results demonstrated structural alterations and cracks of OA menisci accompanied by a very strong β-defensin-4 immunohistochemical staining. The Western blot analysis confirmed also a strong expression of β-defensin-4 in OA fibrochondrocyte cells. The present study suggests an activation of β-defensin-4 induction, in human knee meniscus induced by the OA inflammatory process. It may represent an endogenous antibiotic defense mechanism accompanied by an intrinsic effort of tissue remodeling in OA articular joints. In conclusion, the present paper suggests the clinical relevance of β-defensin-4 in the prospective of future alternative medical treatment for OA.

Both the medial and lateral meniscal allograft transplantation following the anterior cruciate ligament reconstruction by arthroscopic surgical technique

To discuss the minimal invasive arthroscopic surgery technique and clinical results of both the medial and lateral meniscal transplantation following the anterior cruciate ligament reconstruction with double bundles and bone tunnels. In August 2008 a minimal invasive surgery of both the medial and lateral meniscal allograft transplantation following anterior cruciate ligament reconstruction was preformed for 1 case with both the medial and lateral meniscectomy by arthroscopic surgery. The method of two bone plugs attached on tibial plateau was employed for medial meniscal allograft transplantation and the technique the bridge in slot for lateral meniscal allograft transplantation. The VAS, Lysholm score and IKDC rating were recorded before and after operation. The stability of knee was assessed by Lachman test, drawer sign and pivot shift test. The patient was followed up 26 month after the operations. The degrees of knee flexion, extension and function of walk were normal. The Lachman test, drawer sign and pivot shift test were nearly normal. The VAS after operation was 2 points lower than that before operation. The Lysholm score post-operation was 20 points higher than pre-operation. The IKDC became B degree in late following-up from C degree before the operation. MRI revealed anterior cruciate ligament graft was continuous and the meniscal allograft was normal shape on year 1 after the operation. The posterior horn of medial meniscal allograft and anterior corner of lateral meniscal allograft showed slightly shrunk. The second-look arthroscopy showed that the healing occurring between meniscal allograft and the capsule and meniscal allograft was normal shape on month 18 after the operation. The anterior horn of medial and lateral meniscus was slightly worn. Both the medial and lateral meniscal transplantation following the anterior cruciate ligament reconstruction in appropriately selected patients with the medial and lateral meniscus-deficient knee may recover the knee mechanic balance and stability, which is a option of treatment for that young and activity patients. It is proposed that the medial and lateral meniscal grafts harvested from a single donator. Attention should be paid to the direction of the bone tunnels fixing the horns of the meniscus in order to avoid communication with the tunnels of anterior cruciate ligament reconstruction.

Effect of Tunnel Position and Graft Size in Single-Bundle Anterior Cruciate Ligament Reconstruction: An Evaluation of Time-Zero Knee Stability

To determine whether (1) increased graft size with anatomic anterior cruciate ligament reconstruction (ACLR) would confer proportionally increased time-zero biomechanical stability and (2) larger grafts would compensate for the inferior time-zero biomechanical kinematics of nonanatomic, single-bundle ACLR. Ten cadaveric knees were allocated for single-bundle ACLR in an anatomic, center-center or nonanatomic, posterolateral-to-anteromedial footprint position with hamstring autograft. Medial arthrotomy defined the native anterior cruciate ligament (ACL) tibial and femoral footprints. ACLR was performed with a 6-mm semitendinosus graft in 6-mm tunnels and repeated with a 9-mm semitendinosus and gracilis graft in 9-mm tunnels for each knee. Lachman and instrumented pivot-shift examinations assessed knee stability in the ACL-intact, ACL-deficient, and ACLR conditions. Medial and lateral meniscectomies after ACL transection created reproducible pivot shifts. Significance was defined as P < .05. ACLR in the center-center or posterolateral-to-anteromedial position significantly reduced anterior tibial translation compared with the ACL- and meniscus-deficient conditions (P < .001). Larger graft size, however, did not significantly improve time-zero biomechanical stability compared with a smaller graft in the same position for either reconstruction (P = .41 to .74). A center-center ACLR controlled tibial translation significantly better than a nonanatomic graft position regardless of graft size (P < .001). A smaller graft in the anatomic position controlled tibial translation significantly better than a larger graft in a nonanatomic position (P < .001). This study showed that increasing graft size did not improve the time-zero biomechanical stability of the knee after ACLR. Increased graft size did not compensate for the biomechanical instability documented with the nonanatomic tunnel position. Restoration of native footprint anatomy in ACLR is of paramount importance regardless of graft size and source. A larger graft size does not ameliorate the inferior time-zero biomechanics associated with nonanatomic tunnel preparation during single-bundle ACLR.

Intra-articular Findings in Primary and Revision Anterior Cruciate Ligament Reconstruction Surgery

Background: At the time of anterior cruciate ligament (ACL) reconstruction, there are usually concurrent meniscal and articular cartilage injuries. It is unclear if there is a significant difference between intra-articular injuries at the time of a primary ACL reconstruction compared with revision ACL reconstruction. Purpose: To compare the meniscal and articular cartilage injuries found at the time of primary and revision ACL reconstruction surgery and to determine associations between primary and revision surgery and specific intra-articular findings. Study Design: Cohort study (prevalence); Level of evidence, 2. Methods: Primary and revision ACL surgeries were identified from the Multicenter Orthopedic Outcomes Network (MOON) and Multicenter ACL Revision Study (MARS) study groups, respectively, from January 1, 2007 to November 1, 2008. Demographic data on individual patients were analyzed including age, body mass index (BMI), and gender. Intra-articular findings including the presence of medial or lateral meniscal tears and chondral damage to articular surfaces were analyzed for each patient. Comparisons of intra-articular findings at the time of surgery for the 2 groups were analyzed. Chondral damage in the medial and lateral compartments was analyzed considering previous meniscal tear as a possible confounder. Results: There were 508 patients undergoing primary ACL reconstruction and 281 patients undergoing revision ACL reconstruction who were identified for inclusion. There were no differences in the mean age, BMI, and gender in the 2 study groups. There was a decreased odds ratio (OR) of new untreated lateral meniscal tears (OR, 0.54; P < .01) but not of medial meniscal tears (OR, 0.86; P = .39) in revision compared with primary ACL reconstruction. There was an increased OR of Outerbridge grade 3 and 4 articular cartilage injury in revision compared with primary ACL reconstruction in the lateral compartment (OR, 1.73; P = .04) and in the patellar-trochlear compartment (OR, 1.70; P = .04) but not in the medial compartment (OR, 1.33; P = .23). There was an increased OR of Outerbridge grade 3 and 4 articular cartilage injury in patients from both groups having a prior medial meniscectomy on the medial femoral condyle (OR, 1.44; P < .01) and on the medial tibial plateau (OR, 1.63; P < .01). There was an increased OR of Outerbridge grade 3 and 4 articular cartilage injury in patients from both groups having a prior lateral meniscectomy on the lateral femoral condyle (OR, 1.65; P < .01) and on the lateral tibial plateau (OR, 1.56; P < .01). Conclusion: Meniscal tears are a common finding in both primary and revision ACL reconstruction. These results show a decreased OR of new untreated lateral meniscal tears in revision compared with primary ACL reconstruction. A previous medial or lateral meniscectomy increases the OR of articular cartilage damage in the medial or lateral compartments, respectively. Even when controlling for meniscus status, there is an increased OR in revision compared with primary ACL reconstruction of significant lateral compartment and patellar-trochlear chondral damage but not medial compartment chondral damage.

Previous Knee Surgery Is a Risk Factor for Knee Articular Cartilage Lesions Among Athletes at the NFL Combine (SS-29)

Introduction Although articular cartilage lesions of the knee are a common finding among elite athletes, the risk factors for these lesions have not been well defined. The purpose of this study was to better define the prevalence of articular cartilage lesions in elite football players undergoing knee MRI at the National Football League (NFL) Combine and to test the hypothesis that previous knee surgery is a risk factor for these lesions. Methods We performed a retrospective review of all NFL Combine participants undergoing knee MRI from 2005 to 2009. A total of 597 players (726 knee MRIs) were reviewed for evidence of articular cartilage disease, classified as absent, chondromalacia, or full-thickness cartilage loss. History of previous knee surgery (including ACL reconstruction, meniscal procedures, and articular cartilage surgery) was recorded for each athlete. Results Full-thickness articular cartilage lesions were seen in 18% of knees and were associated with a history of any previous knee surgery (p<0.001) and specifically, previous meniscectomy (p<0.001). Full-thickness lesions were present in 29% of knees with a previous meniscectomy compared to 14% of knees without previous meniscal surgery (p<0.001). Full-thickness lesions were found in the lateral compartment of 25% of knees with previous partial lateral meniscectomy compared to 5% of knees without such surgery (p<0.001). The effect was also present in the medial compartment where 2% of knees without previous partial medial meniscectomy had full-thickness lesions compared to 7% of knees with previous partial medial meniscectomy (p=0.025). Previous ACL reconstruction was not associated with an increased risk of full-thickness articular cartilage lesions. Conclusion Previous knee surgery is a risk factor for full-thickness cartilage lesions in athletes participating in cutting contact sports such as American football. Partial meniscectomy increases the risk of full-thickness cartilage lesions, particularly in the lateral compartment. Future research should investigate the effect of these lesions on athlete performance and longevity, as well as potential methods of chondral protection such as meniscal repair in this patient cohort. Although articular cartilage lesions of the knee are a common finding among elite athletes, the risk factors for these lesions have not been well defined. The purpose of this study was to better define the prevalence of articular cartilage lesions in elite football players undergoing knee MRI at the National Football League (NFL) Combine and to test the hypothesis that previous knee surgery is a risk factor for these lesions. We performed a retrospective review of all NFL Combine participants undergoing knee MRI from 2005 to 2009. A total of 597 players (726 knee MRIs) were reviewed for evidence of articular cartilage disease, classified as absent, chondromalacia, or full-thickness cartilage loss. History of previous knee surgery (including ACL reconstruction, meniscal procedures, and articular cartilage surgery) was recorded for each athlete. Full-thickness articular cartilage lesions were seen in 18% of knees and were associated with a history of any previous knee surgery (p<0.001) and specifically, previous meniscectomy (p<0.001). Full-thickness lesions were present in 29% of knees with a previous meniscectomy compared to 14% of knees without previous meniscal surgery (p<0.001). Full-thickness lesions were found in the lateral compartment of 25% of knees with previous partial lateral meniscectomy compared to 5% of knees without such surgery (p<0.001). The effect was also present in the medial compartment where 2% of knees without previous partial medial meniscectomy had full-thickness lesions compared to 7% of knees with previous partial medial meniscectomy (p=0.025). Previous ACL reconstruction was not associated with an increased risk of full-thickness articular cartilage lesions. Previous knee surgery is a risk factor for full-thickness cartilage lesions in athletes participating in cutting contact sports such as American football. Partial meniscectomy increases the risk of full-thickness cartilage lesions, particularly in the lateral compartment. Future research should investigate the effect of these lesions on athlete performance and longevity, as well as potential methods of chondral protection such as meniscal repair in this patient cohort.

Landing adaptations following isolated lateral meniscectomy in athletes

Objective functional outcomes following isolated radial lateral meniscus tears in the athlete between the ages of 14-25 are not clearly defined. The objective of this study was to determine whether patients following lateral meniscectomy demonstrate lower extremity asymmetries relative to control athletes 3months after surgery. We hypothesized that following lateral meniscectomy, athletes aged 14-25years old would demonstrate altered landing biomechanics compared to sex, age, height, weight, and sport-matched controls. A total of 18 subjects were included in this study. Nine patients (7 men and 2 women, 20.1±2.8years) who had undergone first-time isolated radial lateral meniscus tears were tested 3months following partial lateral meniscectomies and compared to nine sex, age, height, weight, and sport-matched controls (7 men and 2 women, 19.7±3.1years). A ten-camera motion analysis system and two force platforms were used to collect three trials of bilateral drop landings. A 2X2 ANOVA was used to test the interaction between side (involved vs. uninvolved) and group (patient vs. control). The patient group landed with a decreased internal knee extensor moment compared to the uninvolved side and controls (interaction P<0.05). The involved limb quadriceps isokinetic torque was not decreased compared to the contralateral or control (n.s.). Decreased knee extensor moments were significantly associated with reduced measures of function (IKDC scores: r=0.69; P<0.05). Athletes who return to sport at approximately 3months following a partial lateral meniscectomy may employ compensation strategies during landing as evidenced by reduced quadriceps recruitment and functional outcome scores. Clinicians should focus on improving quadriceps function during landing on the involved leg in an attempt to decrease residual limb asymmetries. Case-control study, Level III.

Meniscectomy causes significant in vivo kinematic changes and mechanically induced focal chondral lesions in a sheep model

Significant meniscal loss with progression to osteoarthritis is common in humans. In vitro work suggests that meniscectomy causes increased joint contact stress, but what other alterations in dynamic joint actions actually occur remains unknown. In a sheep model, we tested the hypothesis that complete lateral meniscectomy increases joint abduction, shifting the in vivo locations of tibiofemoral contact to regions that qualitatively correspond to locations of chondral damage. Nine sheep underwent unilateral arthrotomy (n = 4) or arthrotomy plus complete lateral meniscectomy (n = 5). Kinematics were collected prior to surgery and serially up to 20 weeks post-surgery. Gross cartilage damage was mapped in each joint, graded using a published scoring scheme used in goats, and compared to the locations of minimum tibiofemoral distance. Over the 20 weeks, meniscectomy caused increased stifle abduction and medial tibial translation, shifting the points of minimum tibiofemoral distance 7.5 ± 2.1 mm laterally and 3.3 ± 1.1 mm anteriorly (mean ± SEM), which corresponded to the locations of focal chondral damage. Locations of new tibiofemoral contact in the meniscectomized compartment qualitatively correspond to subject-specific locations of early chondral damage in an ovine model.

Meniscectomy as a risk factor for knee osteoarthritis: a systematic review

This review defines the recognized risk factors responsible for the development of knee osteoarthritis after surgical management of meniscal tears. We performed a literature search using Medline, Ovid, Cochrane and Google Scholar using the keywords: 'Meniscal tears', 'meniscectomy', 'osteoarthritis', 'complications' and 'risk factors'. Thirty-two published studies were identified. In the long term, osteoarthritis develops in the knee of patients undergoing surgery for meniscal tears. The Coleman methodology score showed great heterogeneity in terms of patient characteristics and outcome assessment. Amount of meniscus removed, duration of pre-operative symptoms and lateral meniscectomy show strong statistical association to onset of knee osteoarthritis. We did not find univocal findings defining the risk factors responsible for the development of post-operative knee osteoarthritis. There is a need for standardized clinical and imaging validated scale to improve definition of post-operative knee osteoarthritis to allow easier and more reliable comparison of outcomes in different studies. Appropriately powered randomized controlled trials reporting clinical and imaging-related outcomes in patients undergoing arthroscopic minimally invasive procedures and meniscal suturing should be performed. Comparing imaging findings of patients undergoing arthroscopic partial and open meniscectomy, a lower incidence of knee osteoarthritic evolution was detected after arthroscopy. The amount of removed meniscus is the most important predictor factor for the development of osteoarthritis. Minimally invasive procedures seem to reduce the incidence of long-term osteoarthritic changes of the knee compared with more invasive open and or arthroscopic procedures.

Arthroscopic Resection of a Bucket Handle Tear of the Meniscus: A Technical Note

Arthroscopic resection of bucket handle tears of the meniscus is difficult owing to the obstructed view of the posterior horn. It often requires an additional portal for access or additional tools. We describe a technique involving conventional tools including grasper, shaver, and basket forceps. No additional portal is required. The basket forceps are used to cut the anterior attachment of the tear, and the bucket handle is shaved to a suitable size. The grasper is then used to hold the remaining meniscus and move it to the posterior space. The posterior corner of the meniscus is then turned over so that its posterior horn can be seen and accessible for cutting. This technique is primarily for medial meniscectomy. For lateral meniscectomy, the conventional technique may suffice, as the lateral compartment can be easily expanded between the femur and tibia.

Arthroscopic Lateral Meniscectomy—Analysis of Cases with Fair Results—

Arthroscopic Lateral Meniscectomy—Analysis of Cases with Fair Results—

Strategies for Repair of Radial Tears Close to the Meniscal Rim—Biomechanical Analysis with a Cyclic Loading Protocol

Background Lateral meniscectomy contributes to early-onset osteoarthritis. Biomechanical properties of sutures repairs for complete radial meniscal tears remain unknown. Hypothesis Double horizontal suture techniques for repair of radial meniscal tears with a shorter distance from the meniscal rim provide significantly higher structural properties than do comparable single-suture techniques with a wider distance from the meniscal rim. Study Design Controlled laboratory study. Methods In 55 fresh-frozen porcine menisci, standardized complete radial meniscal tears were repaired with different distances from the meniscal rim and tear edges and with different numbers of sutures. In group A, the suture was 4 mm from the tear and 8 mm from the meniscal rim; group B, 2 mm from tear; group C, 2 mm from tear, 12 mm from rim; group D, double-loop technique, 2 mm from tear, 5 mm and 10 mm from rim; group E, longitudinal tear sutured with 1 loop, 8 mm from rim, and 4 mm between stitches. The specimens were cyclically loaded 1000 times between 5 and 20 N and loaded to failure. Results All repaired constructs survived the cyclic loading protocol. Compared with the single-loop techniques, the double-loop technique (group D) showed a significantly higher maximum load and yield load and significantly lower displacement after 1000 cycles. Compared with group B, group C had a higher displacement after 1000 cycles (P < .05), and its stiffness showed a descriptive negative trend (P = .09). Displacement after cycling testing in group C was higher than in groups B and D (P < .05). Conclusion Repair of radial meniscal tears with a second suture and shorter distance from the meniscal rim has a positive influence on primary stability. Different distances from tear edges apparently have no influence on structural properties. Clinical Relevance Horizontal sutures for repair of radial meniscal tears provide high stability and can be enhanced with a second horizontal suture and shorter distance from the meniscal rim.

Arthroscopic Treatment of Acute Septic Arthritis After Meniscal Allograft Transplantation

We present the 30-month follow-up results of an acute septic arthritis of the knee after meniscal allograft transplantation, which was successfully treated with graft retention. A 21-year-old man presented with a 4-month history of right knee pain following arthroscopic subtotal lateral meniscectomy. Plain radiographs showed there was no arthritic change with neutral limb alignment. Fourteen days after meniscal allograft transplantation, septic arthritis was confirmed with positive cultures for Staphylococcus epidermidis, and arthroscopic debridement and irrigation were performed. The suggested procedures of our treatment regimen include arthroscopic debridement and irrigation with >or=10 L of normal saline as soon as possible after diagnosis or a clinical suspicion is reached, repeated irrigation under the local anesthesia and intravenous antibiotics until clinical symptoms and laboratory results improve. The decision to repeat the debridement was based on clinical and laboratory results. We reevaluated the patients the third or fourth day after every arthroscopic treatment. At last follow-up, 2 years after the final operation, the patient had no clinical sign of infection. Erythrocyte sedimentation rate and C-reactive protein level were normal and plain radiographs indicated no arthritic change. Further the patient had full pain-free range of knee motion. At this time the Lysholm knee score was 89 and the Tegner score was 5. Magnetic resonance imaging 30 months postoperatively revealed slight (3 mm) extrusion without tear. This case is notable because it shows that early aggressive arthroscopic debridement and repeated irrigation with graft retention can be an effective treatment regimen in selected cases.