Lateral Meniscectomy Research Articles

Anterior Cruciate Ligament Reconstruction After 10 to 15 Years: Association Between Meniscectomy and Osteoarthrosis

To evaluate the stability and arthrosis of the knee 10 to 15 years after arthroscopic-assisted anterior cruciate ligament (ACL) reconstruction with patellar tendon graft. From July 1986 to March 1991, 82 patients underwent arthroscopic-assisted ACL reconstruction with patellar tendon graft. Of these, 62 returned for follow-up evaluation between November 2000 and April 2001. Four different physicians, blinded to each other's examination findings, evaluated the radiologic as well as surgical results according to the International Knee Documentation Committee criteria and the Lysholm knee scoring scale. There were 47 male and 15 female patients. The mean period between injury and surgery was 16 months (range, 2 weeks to 8 years). Results of radiographs were compared with the finding of meniscal lesions during surgery and with International Knee Documentation Committee test results. A statistically significant association (P < .0001) was found between medial or lateral arthrosis of the knee and meniscal injury. In all patients the presence of tears in both menisci was associated with osteoarthrosis in both compartments (medial and lateral). In patients who underwent arthroscopic-assisted ACL reconstruction with patellar tendon graft who also had medial or lateral meniscectomy (or both), arthrosis of the respective compartments developed by 10 to 15 years after reconstruction. Meniscectomy was also associated with poorer results on objective tests of knee function, even with a stable knee joint. Level IV, therapeutic case series.

Osteotomies: The Surgical Treatment of the Valgus Knee

Lateral compartment arthrosis from congenital valgus or the result of previous lateral meniscectomy can be a disabling condition. Realignment osteotomy, which may avoid or delay the need for a total knee replacement, is appropriate for young or middle-aged patients suffering from a painful valgus knee. Medium or large corrections can be managed with distal femoral lateral opening wedge osteotomy while minimal deformities are best treated with medial closing wedge tibial osteotomy.

MRI Evaluation of Isolated Arthroscopic Partial Meniscectomy Patients at a Minimum Five-Year Follow-up

The risk of radiographic knee degeneration after partial or total meniscectomy is well documented, but no prior study has employed cartilage-sensitive MRI technology to assess degenerative changes after meniscectomy. Arthroscopic partial meniscectomy results in early articular cartilage wear and subchondral bony degeneration, even in the absence of clinical symptoms, and these findings can be evaluated with cartilage-sensitive MRI. Retrospective cohort. Twenty-nine patients (ages: 15-40) who had undergone isolated arthroscopic partial medial or lateral meniscectomy with at least 5-year follow-up were evaluated. All patients had arthroscopically normal articular cartilage at the time of initial meniscectomy. Seventeen patients (18 knees) underwent partial medial meniscectomy (MM) and 12 patients underwent partial lateral meniscectomy (LM) with mean follow-up of 8.4 and 7.1 years, respectively. Follow-up evaluation included physical examination, outcome questionnaires, and cartilage-sensitive MRI examination with modified Outerbridge grading of articular surfaces. Outerbridge grades II-IV were noted in 64% of medial compartment joint surfaces in group MM knees versus 33% of lateral compartment joint surfaces in group LM knees. Abnormal cartilage surfaces (grades II-IV), subchondral sclerosis, and condylar squaring were all significantly more frequent after medial meniscectomy (p < 0.05). Groups MM and LM had no significant differences among outcome scores, which remained excellent in both groups. A significant negative correlation was found between the severity of cartilage wear and functional scoring in the MM group, suggesting that functional disability lags behind early MRI evidence of degeneration. Despite optimal preoperative prognostic factors and excellent functional outcomes, MRI evidence of early articular cartilage degeneration was present in both partial medial and lateral meniscectomy patients at a minimum 5-year follow-up. Results support the use of cartilage-sensitive MRI as a noninvasive screening technique to evaluate cartilage changes after arthroscopic partial meniscectomy and may help to counsel the high-risk patient in regard to postoperative activity.

Hydrogel Meniscal Replacement in the Sheep Knee

Background Meniscal allograft transplantation has become a viable surgical alternative for a select group of patients with deficient or irreparable menisci. Subjective results are encouraging; long-term success, durability, and safety of allograft meniscal transplantation are uncertain. Purposes To evaluate a novel hydrogel meniscal replacement implant in an ovine model and assess chondroprotective effects of this hydrogel meniscal replacement using several validated outcome measures. Study Design Controlled laboratory study. Methods Fourteen skeletally mature sheep underwent hydrogel meniscal replacement; 45 additional animals had previously undergone 1 of 3 operations: lateral meniscectomy (24), meniscal allograft transplant (17), and sham (4). Animals were sacrificed at 2, 4, or 12 months. Cartilage was assessed by magnetic resonance imaging, gross inspection, biomechanical testing, and semiquantitative histological analysis. Results There were no differences between the sham operation and nonoperated control limbs. Compared with meniscectomy, hydrogel meniscal replacement resulted in significantly decreased cartilage degeneration with all outcome parameters (P < .05). Compared with nonoperated control limbs, hydrogel meniscal replacements demonstrated no significant differences at 2 months in any category. By 4 months, hydrogel limbs demonstrated significantly greater cartilage degeneration than did nonoperated control limbs in all categories. Compared with meniscal allograft transplantation animals, hydrogel meniscal replacements demonstrated no differences at 2 months but had significantly increased cartilage degeneration in the peripheral zone of the tibial plateau at 4 months (P < .05). At 1 year, all hydrogel implants had developed complete radial splits in the posterior third of the implant. Conclusion Although promising preliminary results for hydrogel meniscal replacement were seen at early time points, significant cartilage degeneration and implant failure were seen at 1 year, and overall performance was worse than was allograft transplantation. Improvements in hydrogel material properties and surface characteristics and more accurate size matching may improve outcomes. Clinical Relevance Improvements in the hydrogel material properties and surface characteristics and more accurate size matching may lead to the use of hydrogel implants in humans.

Le ménisque latéral de l’adulte: En partenariat avec la SFA (Société Française d’Arthroscopie)

Meniscal lesion does not mean meniscectomy and this is particularly true for the lateral meniscus. The reputation of mildness of the meniscectomy is usurped. The rate of joint space narrowing after lateral meniscectomy is of 40% at a follow-up of 13 years compared to 28% for the medial meniscus (symposium SFA 1996). Several arguments explain those results: biomechanical: the lateral meniscus contributes to the congruence; particularly the lateral meniscus is the zone where antero-posterior translational during knee flexion is 12 mm. The pejorative effects of lateral meniscectomy have conducted, more though to the medial meniscus, to the concept of meniscal economy. Lateral meniscectomy must be as partial as possible. Particularly, a discoid meniscus presenting a complete tear should be treated by a meniscoplasty in order to shape the meniscus in a more anatomic form than a total meniscectomy. Lateral meniscectomy is indicated in complex or horizontal cleavage, symptomatic, on stable knees. A particular case is the cyst of the lateral meniscus. It is a cystic subcutaneous formation, usual consequence of a horizontal cleaved meniscus of which the particularity is that it opens besides the articulation. The strategy must not consist in the isolated treatment of the cyst. This pathology should be addressed by an arthroscopic meniscectomy reaching the meniscosynovial junction at the level of the cyst. Meniscal repair must be proposed every time if possible. Criteria of reparability are better studied on MRI. Preoperatively MRI is the first choice radiological exam. Two essential indications can be held back: the vertical peripheral longitudinal lesion is on the non-vascularized area, and the horizontal cleaving of the junior athlete (if the cleaving remains purely intra meniscal). Meniscal repair is highly performed when the meniscal tear is associated to a rupture of the ACL (simultaneous reconstruction of the LCA). Postoperative outcome is different of that of a ″simple″ arthroscopic meniscectomy. The healing process being slow, it suits to protect the suture by a splint in the first month, and with an exclusion of sports with knee torsion during 6 months. Functional results (absence of secondary meniscectomy) and anatomical results (reality of the cicatrisation) are good in 77% of cases (symposium of the French Society of Arthroscopy 2003) at a follow-up of 55 months. Survivorship analysis indicates that majority of the failures occur within two years: this testifies a default of primary cicatrisation. At the studied follow-up, meniscal repair was efficient to protect the cartilage. Lateral meniscus results are better that medial meniscus one. Those data support indications: — All suspicion of meniscal lesion must have an MRI preoperatively to confirm the lesion, to localize her and to search criteria of reparability; — All vertical longitudinal peripheral lesions can and must be repaired especially in young patients and children; — All horizontal cleaving of the junior athlete should be treated by open repair; Surgical abstention must be proposed when the lesion is non symptomatic, or when le lesion is limited and associated to an ACL tear (in that case isolated ACL reconstruction is proposed), or when clinical symptoms are minimal; — Meniscectomy, always arthroscopic, is proposed for a symptomatic lesion in the avascular zone or for a deep horizontal cleavage or a complex tear; — Tear of the discoid meniscus should be treated by meniscoplasty. A painful knee after lateral meniscectomy might be due to a too limited initial meniscectomy: an iterative meniscectomy may be indicated or lateral femorotibial arthritis, especially after subtotal or total meniscectomy. In this last case and after failure of usual medical treatment such as viscosupplementation surgery may be indicated. Osteotomy in order to unload the lateral femorotibial compartment gives a partial response as the shearing forces remain. This osteotomy is indicated only if the lower limb axis is normal or in valgus. Meniscal allograft is an option in young patients in grade I or II arthritis. Results are promising. Rene Verdonk's series show a survivorship analysis of 75% at 7 years. Early diagnosis of a postmeniscectomy syndrome before cartilaginous lesions occur is essential for an adapted treatment. In conclusion, lateral meniscectomy are less frequent than those of the medial meniscus but their prognosis is less favorable. They should be early diagnosed (MRI). Treatment options are various: abstention, meniscectomy, and repair. Painful post lateral meniscectomy syndrome may be treated by a new surgical option: meniscal allograft.

Meniscal Allograft Transplantation in the Sheep Knee

Background Early protection of articular cartilage, before degenerative changes appear on radiographs, should result in better long-term results, but scientific evidence regarding the effectiveness of meniscal transplantation is lacking. Purpose To assess the chondroprotective effects of a new meniscal allograft transplantation animal model and evaluate a magnetic resonance imaging parameter, T2 mapping, in articular cartilage after meniscectomy and meniscal transplantation. Study Design Controlled laboratory study. Methods Forty-five skeletally mature sheep were placed into 3 surgical groups lateral meniscectomy (n = 24), meniscal allograft transplant (n = 17), and sham (n = 4). Animals were sacrificed at 2, 4, or 12 months. Cartilage was assessed by gross inspection, magnetic resonance imaging, T2 mapping, biomechanical testing, and semiquantitative histologic analysis. Results There were no differences between the sham operation and nonoperated control limbs. Compared with control limbs, meniscectomy resulted in significant increases in cartilage degeneration by all objective criteria (P < .01). Compared with meniscectomy, meniscal allograft transplantation resulted in significant decreases in cartilage degeneration (P < .02). There were significant correlations between T2-mapping data and all other traditional outcomes measures (P < .05, r2 = 0.37-0.67). Compared with the nonoperated control limbs, allograft transplants demonstrated no significant differences at 2 months in any category, except magnetic resonance imaging data. By 4 months, nonoperated control limbs demonstrated significantly less wear compared to allograft limbs in all categories except modified Mankin scores. Conclusion This model demonstrated significant chondroprotection compared with meniscectomy but demonstrated more cartilage wear at 4 months compared to control limbs. A high degree of allograft cell viability and vascular ingrowth was seen in allograft explants. T2 mapping may provide an accurate noninvasive measure of early cartilage degeneration after meniscectomy, as well as cartilage protection after meniscal allograft transplantation. Clinical Relevance This study establishes a reliable animal model for meniscal allograft transplantation and provides evidence for the utility of T2 mapping at clinically relevant magnetic resonance imaging field strengths for evaluation of early cartilage degeneration.

Arthroscopic Lateral Meniscectomy in Knees With Lateral Compartment Osteoarthritis: A Case Series Study

The purpose of this study was to investigate the intermediate-term postoperative results of arthroscopic surgery for lateral compartment osteoarthritis (OA) of the knee in a case series study. In a series of 30 knees in 29 patients who underwent arthroscopic surgery for lateral compartment OA, we were able to observe 25 joints in 24 patients prospectively for the entire postoperative period. The follow-up period ranged from 1 to 13 years, with a mean of 5.5 +/- 3.7 years. The procedure in all cases comprised lateral partial meniscectomy with either abrasion arthroplasty, or debridement of the articular cartilage surface or microfracture. Of 25 cases, 13 underwent abrasion arthroplasty, 10 underwent debridement of the articular cartilage surface, and 2 underwent microfracture. Results were assessed by use of the postoperative knee score, findings of arthritic changes on plain knee radiographs, and other measurements of postoperative progress. Further surgery was required in 2 cases (8%) because of poor postoperative progress. In the remaining 22 patients, knee scores improved from a mean of 52.4 points preoperatively to 84.6 points postoperatively and mean function scores improved from 45.4 points to 82.6 points, with these favorable results being maintained at the last follow-up. The femoral-tibial angle decreased slightly as each year passed postoperatively. Radiologic progression of OA was seen at 3 years postoperatively in 7 patients (28%), but no progression was seen in 12 (48%). A positive correlation was seen between the preoperative femoral-tibial angle and postoperative results (R = 0.81, P < .01). When lateral compartment OA and lateral meniscal tears are both present, the clinical outcome of lateral meniscal resection was favorable. In patients with lateral compartment OA, therefore, an arthroscopic procedure, including meniscectomy, should be considered early. Level IV, therapeutic case series.

Meniscus-Stabilizing Function of the Meniscofemoral Ligament: Experimental Study of Pig Knee Joints

To demonstrate experimentally, with the use of pig knee joints, that the posterior meniscofemoral ligament (PML) stabilizes the lateral meniscus (LM). Amputated stumps of the knee joints of Yorkshire pigs, which are anatomically similar to human knee joints, were used. The PML was intact or was cut according to 1 of 6 different conditions: (1) intact PML with intact LM, (2) intact PML with a radial tear of the posterior horn of the LM, (3) intact PML with total lateral meniscectomy, (4) cut PML with intact LM, (5) cut PML with a radial tear of the posterior horn of the LM, and (6) cut PML with total lateral meniscectomy. Pressure-sensitive film was inserted beneath the lateral femoral condyle, an axial load of 150 kg was placed on the knee joint with a universal testing machine, and the pressed area and maximum and average pressures were measured with the Prescale Imaging Analysis System (Fujifilm Medical Systems, Stamford, CT). With an intact PML, no difference was seen between the intact meniscus and the radial tear of the posterior horn of the LM in pressed area and maximum and average pressures. With a cut PML, pressure concentration, detected as significantly reduced pressed area and increased maximum and average pressures, was observed, regardless of the condition of the LM. PML of the pig stabilized the LM under an axial load, and an intact PML yielded results similar to those observed in total lateral meniscectomy. Our findings suggest that posterior horn tears of the LM, which are rarely symptomatic, may be caused by stabilizing of the lateral meniscus by the PML against the load placed on the knee joint. Findings suggest that the PML, lateral side, stabilizes the LM when the ligament is intact. Even when a tear of the meniscus occurs, no increased localized pressure areas appear on the meniscus; this may explain why these tears are rarely symptomatic.

Rapid chondrolysis after arthroscopic partial lateral meniscectomy in athletes: a case report

We present a patient with a severe chondrolysis after arthroscopic partial lateral meniscectomy in a 17-year-old high school basketball player. This is a rare but severe complication after arthroscopic partial lateral meniscectomy. At 7 months after the first operation, a second-look arthroscopy showed numerous cartilaginous debris floating in the knee and a high-grade cartilage damage on the lateral compartment of the tibia. This unexpected complication and a consideration of its etiology are shown.

Why lateral meniscectomy is more dangerous than medial meniscectomy. A finite element study

Total meniscectomies are commonly thought to cause progressive degenerative arthrosis pathology in articular cartilage in a period of a few years because of alteration of the biomechanical environment including increased joint instability. This concern has lead to a preference for partial meniscectomies, although lateral partial meniscectomies sometimes lead to catastrophic results. We performed a three-dimensional finite element model of the human tibiofemoral joint to examine the effect of lateral meniscectomy on knee biomechanics. The results were compared to those from modeling a medial meniscectomy. Under axial femoral compressive loads, the peak contact stress and maximum shear stress in the articular cartilage increased 200% more after a lateral than a medial meniscectomy. These increased stresses could partly explain the higher cartilage degeneration observed after a lateral meniscectomy.

Iliotibial band friction syndrome after anterior cruciate ligament reconstruction using the transfix device: report of two cases and review of the literature

The use of hamstrings is increasing as a treatment for anterior cruciate ligament (ACL) injuries. There are a lot of new devices and techniques that try to fix the graft without causing further injury or increased morbidity. We report two cases in relation to the transfix device for reconstructing the ACL. The first case is a 38-year-old female who was treated with an autologous hamstring graft for chronic ACL instability brought on by a sport trauma. The patient developed iliotibial band friction syndrome 3 months after the operation. MRI showed incorrect positioning and a rupture of the femoral bio-absorbable cross-pin. The hamstring graft always had good fixation and did not produce instability of the knee. We removed the cross-pin fragment in a second surgery and the patient returned to her daily lifestyle after 3 weeks. The second case is a 52-year-old female with a painful and unstable knee due to a previous lateral meniscectomy and failure of an ACL reconstruction. We performed an ACL reconstruction with an autologous hamstring graft and a lateral meniscus transplantation. Some months after the procedure she also developed this syndrome. MRI showed the same features as shown in the first case and a second surgery was needed. To our knowledge this clinical and technical problem has not been previously described.

Rapid Progression of Chondral Disease in the Lateral Compartment of the Knee Following Meniscectomy

We present 2 cases of severe, rapidly progressive chondral disease in the lateral compartment within 12 months after meniscectomy. In both cases, the lateral compartment was salvaged with simultaneously performed cartilage repair techniques and meniscal transplantation. The first case is of a 16-year-old boy who suffered a complex irreparable posterior horn lateral meniscus tear that was treated with an aggressive partial meniscectomy, and developed a rapid onset of severe lateral compartment symptoms associated with a focal grade IV chondral defect of the lateral femoral condyle within 10 months of his index meniscectomy. The second case is that of an athletic 43-year-old orthopaedic surgeon who suffered a complex lateral meniscus tear that required a near total lateral meniscectomy. Within 5 months of the lateral meniscectomy, he developed severe lateral symptoms with a focal grade IV chondral defect of the lateral femoral condyle. In both cases, the articular cartilage defects were treated with osteochondral grafting at the time of lateral meniscus transplantation with excellent results at 2-year follow-up. These cases highlight the significant need for a heightened the awareness of the relatively increased risk of rapid lateral compartment degeneration following lateral meniscectomy. This, in combination with the appropriate use of cartilage restoration techniques, provides the potential to salvage or prevent rapid onset, unicompartmental degenerative disease, and the ability to reduce symptoms and improve function in these challenging patients.

Type II collagen synthesis in the articular cartilage of a rabbit model of osteoarthritis: expression of type II collagen C-propeptide and mRNA especially during early-stage osteoarthritis

BackgroundThe aim of this study was to observe time course changes in type II collagen synthesis in various regions of articular cartilage affected with osteoarthritis (OA) by examining the expression of type II collagen C-propeptide (pCOL II-C) and mRNA in a rabbit OA model. MethodsOsteoarthritis was experimentally induced by partial lateral meniscectomy in the knees of Japanese white rabbits. The cartilage of the animals was then examined histologically over time. The degenerative area of articular cartilage was divided into three areas, according to the degree of degeneration. The ability to synthesize type II collagen was estimated by the immunohistological staining of pCOL II-C and the in situ hybridization of mRNA in type II collagen. ResultsThe positive rate of pCOL II-C immunostaining in chondrocytes was highest in the central-degenerative region 1week after surgery, and the highest rate in the para-degenerative region was observed 2 and 4weeks after surgery. The percentage of pCOL II-C positive cells increased as the histological degeneration score increased to moderate degeneration and then decreased with further progression of the severity of cartilage degeneration. Examination by in situ hybridization revealed that the regions marked by strong pCOL II-C mRNA expression were similar to those indicated by the immunohistology results. ConclusionsThese results suggest that the type II collagen-synthesizing potential of chondrocytes is highest in moderately degenerated areas of OA articular cartilage. Cartilage repair continues to be seen even as OA advances, although the reaction varies depending on the stage of OA.

Patellofemoral Replacement

Patellofemoral Replacement

Arthroscopic Diagnosis of the Snapping Popliteus Tendon

Abstract The syndrome of the snapping popliteus tendon is a rare cause of lateral knee pain and may be difficult to diagnose, leading to patients undergoing inappropriate therapy or surgical intervention. In this report, we describe the arthroscopic findings of the snapping popliteus tendon. Two men and 1 woman presented complaining of pain and a snapping sensation at the lateral aspect of the knee. No clear traumatic history was reported by any of the patients. Two patients had previously undergone partial lateral meniscectomy without relief of their symptoms. While the only consistently positive clinical sign was the Cabot sign, the arthroscopic findings confirmed the diagnosis in all cases. We observed in all cases inflammation around the tendon and visualized the portion of popliteus tendon near its insertion that is usually hidden by the femoral condyle. Further, flexion and extension with the limb in the tailor position revealed the snapping popliteus tendon. Successful treatment was achieved by securing the popliteus tendon to its sulcus on the lateral femoral condyle. Arthroscopic examination helps the surgeon to identify the snapping popliteus tendon to better treat this simple, yet oftentimes perplexing, condition.

Multiple osteochondral arthroscopic grafting (mosaicplasty) for cartilage defects of the knee: Prospective study results at 2-year follow-up

To prospectively evaluate the mosaicplasty technique for treatment of femoral condyle cartilage lesions (Outerbridge grade IV) less than 2.5 cm2 in homogeneous group of young active patients. Case series. Thirty-seven patients (10 female, 27 male; mean age, 29.5 years) with full-thickness knee chondral lesions were treated by the arthroscopic mosaicplasty technique. All patients practiced sports. There were 12 ACL reconstructions, 11 medial meniscectomies, and 8 lateral meniscectomies associated; 10 meniscectomies, 9 ACL reconstructions, and 5 cartilage reparative operations had been previously performed. All patients were evaluated at a 2-year follow-up. The International Cartilage Repair Society (ICRS) form, return to sports, computed tomography, or magnetic resonance imaging were used for clinical evaluation. In some cases, second-look arthroscopy was performed. The ICRS showed 78.3% good and excellent results; 27 patients returned to sports at the same level and 5 at a lower level, but 5 were not able to resume sports. Results in the lateral condyles were significantly better than those in medial condyles, and younger patients had a better clinical outcome than did older patients. Cases with associated surgery had better clinical results; previous surgery did not significantly influence the clinical outcome. The results of this technique at medium-term follow-up are encouraging with 78.3% clinically satisfactory results. Better results can be obtained in young patients with associated surgery, with localized grade 4 lesions of the lateral condyles. This arthroscopic 1-step surgery appears to be a valid solution for the treatment of grade III-IV cartilage defects not more than 2.5 cm2. Level IV, Case Series.

The nitric oxide donor glyceryl trinitrate increases subchondral bone sclerosis and cartilage degeneration following ovine meniscectomy

To examine the effect of glyceryl trinitrate (GTN), a nitric oxide (NO) donor compound, on the concurrent progression of cartilage and subchondral bone changes in an ovine meniscectomy model of osteoarthritis (OA). Bilateral lateral meniscectomy (MX) was performed on 12 ewes to induce OA. Six were treated with topical GTN (0.7mg/kg twice weekly) (MX+GTN). Six other sheep formed non-operated controls (NOC). After sacrifice at six months, the subchondral bone density (BMD) of the lateral and medial femoral condyles (LFC, MFC) and tibial plateau (LTP, MTP) was assessed by DEXA. Dynamic biomechanical testing was performed across the MTP and LTP. Histological sections from each region were scored qualitatively and the thickness of the subchondral bone plate (SCB) was determined by image analysis. MX+GTN displayed significantly greater SCB thickness relative to MX in the LFC (mean increase +88% and +42%, respectively) and the MFC. SCB BMD was 10-12% greater in MX+GTN relative to MX in the LFC, LTP and MTP. MX+GTN sheep also showed greater increases in some histopathology variables, greater central erosion of the LTP, and changes in dynamic stiffness (decreased) and phase lag (increased) in the outer zone of the LTP. Treatment with GTN significantly increased subchondral bone thickness and density during subchondral remodelling following meniscectomy. In addition, it slightly but significantly worsened degeneration of cartilage structure and function. These results suggest that clinical use of GTN may accelerate both cartilage degeneration and subchondral bone sclerosis if used in the presence of OA, and demonstrate that NO has the potential be an important mediator of the subchondral bone changes seen in OA.

Arthroscopic treatment of 105 lateral meniscal cysts with 5-year average follow-up.

To evaluate meniscal damage and the midterm clinical outcome, we performed a retrospective review of 105 lateral meniscal cysts that were treated arthroscopically at our institution. Retrospective review. From a series of 8,100 knee arthroscopies, 122 patients (1.5%) with 124 lateral meniscal cysts were selected. Eight of the patients were lost to follow-up and 11 patients had associated pathology; therefore, 105 lateral meniscal cysts on stable knees were included in this study. Average follow-up was 5 years (range, 1 to 12.5 years). The mean age was 33 years (range, 12 to 69 years). All patients had presented with tenderness over the joint line with a palpable mass. All cases were treated arthroscopically and all patients underwent a complete physical examination before surgery and at last follow-up. Radiographic evaluation was available at final follow-up for 68 cases. All patients had a meniscal tear at the time of surgery and 60 (57%) had a horizontal cleavage component. For meniscal tears, arthroscopic partial lateral meniscectomy was performed in 104 cases and meniscal repair in 1 case. For cysts, intra-articular debridement was performed in 91 cases and open cystectomy in 14. Eleven cysts recurred and a second arthroscopy was required. The clinical results, including those cases with recurrent cysts, were excellent or good in 87% of cases. Osteoarthritis following treatment for meniscal cysts occurred in 9% of cases. When there was a cyst and no other intra-articular damage, the prognosis was excellent. For lateral meniscal cysts, arthroscopic partial meniscectomy with intra-articular debridement yields predictable results. Level IV.

Risk factors for symptomatic knee osteoarthritis fifteen to twenty-two years after meniscectomy.

To evaluate the influence of age, sex, body mass index (BMI), extent of meniscal resection, cartilage status, and knee load on the development of radiographically evident osteoarthritis (OA) of the knee and knee symptoms after meniscal resection. We evaluated 317 patients with no cruciate ligament injury (mean +/- SD age 54 +/- 11 years) who had undergone meniscal resection 15-22 years earlier (followup rate 70%), with radiographic and clinical examination. The Knee injury and Osteoarthritis Outcome Score was used to quantify knee-related symptoms. Sixty-eight unoperated subjects identified from national population records were included as a reference group. Symptomatic radiographic OA (corresponding to Kellgren/Lawrence grade > or =2) was present in 83 of 305 operated knees (27%) and 7 of 68 control knees (10%) (relative risk 2.6, 95% confidence interval [95% CI] 1.3-6.1). Patients who had undergone total meniscectomy and subjects with obesity (BMI > or =30) had a greater likelihood of tibiofemoral radiographic OA than those who had undergone partial meniscal resection and those with a BMI <25, respectively. Furthermore, degenerative meniscal tear, intraoperative cartilage changes, and lateral meniscectomy were associated with radiographic OA more frequently than were longitudinal tear, absence of cartilage changes, and medial meniscectomy, respectively. Symptomatic tibiofemoral or patellofemoral radiographic OA was associated with obesity, female sex, and degenerative meniscal tear. Contributing risk factors for OA development after meniscal resection are similar to risk factors for common knee OA. Systemic factors and local biomechanical factors interact. Obesity, female sex, and preexisting early-stage OA are features associated with poor self-reported and radiographic outcome. Partial meniscal resection is associated with less radiographic OA over time than is total meniscectomy.

The long-term evaluation of lateral meniscus tears left in situ at the time of anterior cruciate ligament reconstruction

Purpose: The goal of this study was to determine the long-term subjective and objective results for patients with lateral meniscus tears found at the time of anterior cruciate ligament (ACL) reconstruction that were left in situ or abraded and trephined but not repaired or removed. Type of Study: Retrospective review of prospectively collected data. Methods: From a database of ACL reconstruction patients, 332 patients were noted to have lateral meniscus tears that were left in situ or underwent abrasion and trephination. Exclusion criteria included lateral or medial partial meniscectomy, previous knee surgery, or greater than grade II chondromalacia in any knee compartment. The tears were classified as posterior horn tears (n = 70), stable radial flap tears (n = 50), or peripheral or posterior tears (n = 212). Patients were evaluated subjectively using a modified Noyes knee questionnaire and objectively using International Knee Documentation Committee (IKDC) criteria. Results: At a mean of 6.6 years (range, 2 to 16.5 years) after surgery, the mean total modified Noyes score for 239 patients was 93.8 ± 7.6 points. At a mean of 5.1 ± 3.8 years after surgery, the objective IKDC evaluation showed that 163 of 170 (96%) patients had an overall rating of normal or nearly normal. Radiographic evaluation showed that 162 patients (95%) had a normal rating, 6 patients had a nearly normal rating and 2 patients had an abnormal rating. Of 332 patients, only 8 (2.4%) required subsequent surgery for the lateral meniscus. Conclusions: Lateral meniscus tears that are posterior horn tears, stable radial flap tears, or peripheral or posterior third tears that do not extend further than 1 cm in front of the popliteus tendon can be treated successfully with abrasion and trephination or by being left in situ. Level of Evidence: Level III, retrospective cohort study.