Background: Repair of a posterior root tear of the medial meniscus (MRT) decreases peak contact pressure by restoring hoop tension and is expected to prevent progression to osteoarthritis.
Purpose: The purposes of this study were (1) to report the clinical and magnetic resonance imaging (MRI) results of arthroscopic pull-out repair of the MRT and (2) to identify prognostic factors of poor outcome.
Study Design: Case series; Level of evidence, 4.
Methods: Fifty-one patients (47 women, 4 men) who underwent arthroscopic pull-out repair of the MRT by a single surgeon were enrolled. Mean follow-up after surgery was 33 months (range, 24-44 months). To identify factors affecting final outcome, patient-specific factors, such as gender, age, body mass index, meniscus extrusion, extrusion increase, subchondral edema, degree of varus alignment (<5° or >5°), and cartilage status in the medial compartment (Outerbridge grade 1 or 2 lesion vs grade 3 or 4 lesion), were investigated. Final clinical outcomes were determined using a visual analog scale (VAS) for pain and patient satisfaction scores, American Knee Society (AKS) scores, and Lysholm scores, and MRI outcomes were determined by evaluating meniscus extrusion and articular cartilage status. Multiple regression analysis was performed to identify variables that independently affected clinical and MRI-determined outcomes.
Results: All clinical outcome measures significantly improved after surgery. Patients with Outerbridge grade 3 or 4 chondral lesions had poorer results than those with grade 1 or 2 lesions in terms of AKS function and Lysholm scores. Patients with varus alignment of >5° had poorer results than those with varus alignment of <5° in terms of VAS satisfaction, AKS function, and Lysholm scores. Mean meniscus extrusion increased from 3.6 mm preoperatively to 5.0 mm postoperatively. Chondral lesions progressed in 3 (9.7%) of 31 patients. Preoperative meniscus extrusion was found to be positively correlated with final extrusion.
Conclusion: At a mean follow-up of 33 months after pull-out repair, extrusion of the meniscus was found to have progressed. Nevertheless, this technique provided patients with a clinical benefit. Outerbridge grade 3 or 4 chondral lesions and varus alignment of >5° were found to independently predict an inferior clinical outcome.
Background: Arthroscopic meniscal repair techniques are continuing to evolve. Most studies to date comparing the healing rate of inside-out to all-inside meniscal repair techniques are confounded by associated anterior cruciate ligament reconstruction or deficiency.
Purpose: This review was conducted to compare the effectiveness and complications of the inside-out repair technique to that of the all-inside repair technique in isolated unstable peripheral longitudinal (”bucket-handle”) meniscal tears.
Study Design: Systematic review.
Methods: Computerized keyword searches of MEDLINE, EMBASE, CINAHL, ACP Journal Club, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews were performed. Two reviewers independently performed searches and article reduction. Studies that included stratified data for isolated unstable longitudinal meniscal tears in stable knees, repaired with either an inside-out or all-inside repair technique, were selected. Data on clinical failure, subjective outcome measures, and complications were summarized.
Results: Nineteen studies included data specific to isolated meniscal tears. The rate of clinical failure was 17% for inside-out repairs and 19% for all-inside repairs. Lysholm scores and Tegner activity scores were similar between the 2 repair methods (87.8 vs 90.2 and 5.6 vs 5.5, respectively). The prevalence of nerve injury/irritation was higher with the inside-out technique (9% vs 2%). All-inside techniques had a higher rate of local soft tissue irritation, swelling, and implant migration or breakage. The use of older generation, rigid, all-inside implants is associated with chondral injury.
Conclusion: There are no differences in clinical failure rate or subjective outcome between inside-out and all-inside meniscus repair techniques. Complications are associated with both techniques. More nerve symptoms are associated with the inside-out repair and more implant-related complications are associated with the all-inside technique.
Clinical Relevance: Rates of structural healing and complications are comparable for inside-out and all-inside repair techniques for isolated meniscal injury. Differences in observed healing rates after meniscal repair may be more dependent on tear pattern and associated anterior cruciate ligament reconstruction rather than an inside-out versus all-inside surgical approach.
Background: The failure rate after arthroscopic meniscal repair ranges from 5% to 43.5% (mean, 15%) in the literature. But little is known about the amount of meniscal tissue removed after failed meniscal repair.
Hypothesis: The volume of subsequent meniscectomy after failed meniscal repair is not increased when compared with the volume of meniscectomy that would have been performed if not initially repaired.
Study Design: Case series; Level of evidence, 4.
Methods: From January 2000 to December 2009, 295 knees underwent arthroscopic meniscal repair for unstable peripheral vertical tears. When present (219 cases), all anterior cruciate ligament (ACL) tears underwent reconstruction. Patients with multiple ligament injuries and posterior cruciate ligament injuries were excluded from the analysis. Thirty-two medial and 5 lateral menisci underwent subsequent meniscectomy after failed repair at a mean of 26 months postoperatively (range, 3-114 months). Five parameters were specifically evaluated: the amount of meniscectomy related to the initial tear, the ACL status, the appearance of chondral lesions, the time from the initial injury to meniscal repair, and the time from repair to meniscectomy.
Results: The posterior segment of the meniscus was involved in all tears and retears. Among failures, resection of the meniscal segments primarily repaired occurred for 17 medial and 2 lateral meniscal tears (52%); the tear extended in 5 cases (all medial menisci), and healing of some repaired segments led to a partial resection of the initial lesion in 35% of cases (10 medial menisci, 3 lateral menisci). The time from injury to meniscal repair was correlated with an increasing volume of meniscus removed (P < .05) and with the presence of stage 2 or 3 chondral lesions at revision (P < .03). All knees with extended tears (5 cases) and/or with significant chondral degeneration (8 cases) occurred in ACL-reconstructed knees. Among them, 50% (6 of 12) of ACL-reconstructed knees were ACL deficient.
Conclusion: There are few detrimental effects when repairing a repairable meniscal lesion, even if it fails. The amount of meniscectomy is rarely increased when compared with the initial lesion. This study supports the hypothesis that the meniscus can be partially saved and that a risk of a partial failure should be taken when possible.
Background: Consistency of arthroscopic evaluation and documentation in meniscal tears between investigators is essential to the validity of multicenter studies. A group of experts developed a classification of meniscal tears that may be used internationally.
Hypothesis: The International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) classification of meniscal tears provides sufficient interobserver reliability for pooling of data from international clinical trials designed to evaluate the outcomes of treatment for meniscal tears.
Study Design: Cohort study (diagnosis); Level of evidence, 1.
Methods: A pilot study was performed by having 8 members of the committee grade 10 arthroscopic videos for classification of tear depth, rim width, location, tear pattern, and quality of the tissue. The results of the pilot study were used to change the instruction sheet and evaluation form. International interobserver reliability was determined by having 8 orthopaedic surgeons who practice in different countries evaluate 37 arthroscopic videos selected to represent different meniscal tear characteristics. The Spearman correlation coefficient was used to compare the area of the meniscus excised, as drawn on the diagram, with the numeric percentage of meniscus excised.
Results: There was an 87% agreement for anterior-posterior location of the tear ( = .65); 79% agreement for tear pattern ( = .72); 88% agreement for tear depth ( = .52); 68% agreement for anterior, middle, and posterior location of the tear ( = .46); and 72% agreement for tissue quality ( = .47). There was 54% agreement for the rim width ( = .25) and 67% agreement if the tear was central to the popliteal hiatus ( = .36). Based on the Landis and Koch criteria for coefficients, there was substantial agreement for anterior-posterior location of the tear and tear pattern; moderate agreement for tear depth, anterior, middle, and posterior location of the tear, and tissue quality; and fair agreement for rim width and if the tear was central to the popliteal tear. Interobserver reliability based on the intraclass correlation coefficient (ICC) was good for tear length (ICC = .83) and moderate for percentage of meniscus that was excised (ICC = .65). The mean for all raters was .92 (95% confidence interval [CI], .89-.94) comparing the values for percentage of meniscus excised with the area on the diagrams.
Conclusion: The ISAKOS classification of meniscal tears provides sufficient interobserver reliability for pooling of data from international clinical trials designed to evaluate the outcomes of treatment for meniscal tears.
Background: Radial meniscal tears historically have been treated by partial meniscectomy, although they are more biomechanically detrimental than longitudinal tears. Clinical results after meniscal repair for radial tears of the midbody of the lateral meniscus have been reported rarely.
Study Design: Case series: Level of evidence, 4.
Methods: Fourteen consecutive patients who had radial tears of the midbody of the lateral meniscus underwent arthroscopic repair. Inclusion criteria were radial tears involving the red-red or red-white zone. All patients underwent all-inside meniscal repair using absorbable sutures. Postoperative evaluation was performed using joint-line tenderness, McMurray test, range of motion, and follow-up magnetic resonance imaging (MRI) scan at 6 months postoperatively. Lysholm knee score and Tegner activity level were evaluated at last follow-up. In 4 patients, second-look arthroscopies were performed.
Results: The average follow-up was 36.3 months. No patient had joint-line tenderness. Three patients complained of pain or a click on McMurray test. The mean follow-up range of motion was 138.6°. Follow-up MRI scans demonstrated that 5 (35.7%) menisci were healed, 8 (57.1%) were partially healed, and 1 (7.1%) was not healed. The follow-up Lysholm score was 94.7 (range, 81-100; standard deviation [SD] = 6.4) and Tegner score was 5.7 (range, 3-7; SD = 1.4). Second-look arthroscopies in 4 patients showed partial healing of meniscal tears.
Conclusion: Meniscal repair for radial tears of the midbody of the lateral meniscus may be an effective, alternative treatment to partial meniscectomy.
Background: The influence of standard meniscus treatment strategies regarding osteoarthritic progress, function, and sports activity has not been estimated in a direct long-term comparison.
Hypothesis: Meniscal repair compared with partial meniscectomy (partial meniscal resection) decreases osteoarthritic changes and reduces the effect on sports activity in the long-term follow-up.
Study Design: Cohort study; Level of evidence, 3.
Methods: Eighty-one patients with an arthroscopic meniscus shape–preserving surgery after isolated traumatic medial meniscal tear (repair: n = 42; meniscectomy: n = 39) were examined clinically (Lysholm score, Tegner score) and radiologically (Fairbank score, compared with the uninjured knee); the follow-up was divided into midterm (3.4 years; n = 35) and long term (8.8 years; n = 46). Additionally, the influences of the preoperative sports activity level and age at surgery were evaluated.
Results: In the long-term follow-up, no osteoarthritic progress was detectable in 80.8% after repair compared with 40.0% after meniscectomy (P = .005) with significant benefit for the “young” subgroup (P = 0.01). The preinjury activity level was obtained in 96.2% after repair compared with 50% after meniscectomy (P = .001). The function score revealed no significant difference between these strategies (P = .114). The athletes showed a significantly reduced loss of sports activity after repair compared with the athletes after meniscectomy (P = .001).
Conclusion: Arthroscopic meniscal repair offers significantly improved results for isolated traumatic meniscal tears regarding the long-term follow-up in osteoarthritis prophylaxis and sports activity recovery compared with partial meniscectomy.
