The Role of Arthroscopic Partial Meniscectomy in the Management of Degenerative Meniscus Tears: A Review of the Recent Literature

Arthroscopic surgery or exercise therapy for degenerative meniscal lesions: a systematic review of systematic reviews

BACKGROUND

Arthroscopic partial meniscectomy (APM) is widely applied for the treatment of degenerative meniscal lesions in middle-aged patients; however, such injury is often associated with mild or moderate osteoarthritis and has been reported by MRI in asymptomatic knees. Previous studies suggested, in most patients, a lack of benefit of surgical approach over conservative treatment, yet many controversies remain in clinical practice. Our aims were to assess the functional and pain scores between exercise therapy and arthroscopic surgery for degenerative meniscal lesions and to evaluate the methodological quality of the most recent systematic reviews (SRs).

METHODS

Two authors independently searched PubMed and Google Scholar for SRs comparing the outcome (in knee pain and functionality) of arthroscopic treatment and exercise therapy or placebo for degenerative meniscal lesions. The timeframe set was from 2009 to 2019 included.

RESULTS

A total of 13 SRs were selected. Two reviewers independently assessed the methodological quality of each paper using the AMSTAR 2 tool: seven scored as "moderate," four obtained a "low" grade while the remaining two were evaluated as "critically low." SRs agreed that in middle-aged patients with degenerative meniscal lesions arthroscopic surgery appears to grant no long-term improvement in pain and function over exercise therapy or placebo.

CONCLUSIONS

Conservative treatment based on physical therapy should be the first-line management. However, most SRs revealed subgroups of patients that fail to improve after conservative treatment and find relief when undergoing surgery. In the future, randomized controlled trials, evidence should be looked for that APM can be successful in case of the unsatisfactory results after physical therapy.

Preoperative Patient-Centric Predictors of Postoperative Outcomes in Patients Undergoing Arthroscopic Meniscectomy

PURPOSE

To determine the minimal clinically important difference (MCID) using Patient-Reported Outcome Measurement Information System (PROMIS) computer-adaptive testing assessments in patients undergoing arthroscopic partial meniscectomy. The secondary purpose was to identify which preoperative patient factors are associated with MCID achievement.

METHODS

Three PROMIS computer-adaptive testing assessments (Physical Function [PF], Pain Interference [PI], and Depression [D]) were administered to all patients presenting to 1 of 2 board-certified, sports medicine orthopaedic surgeons. Patients with Current Procedural Terminology codes of 29880 or 29881 were chart reviewed for a host clinical and demographic factors. PROMIS scores were assessed for improvement and patient characteristics were assessed for influence on any improvement. MCID was calculated according to the distribution methodology and receiver operating characteristics were used to assess preoperative scores predictive ability.

RESULTS

In total, 166 patients met inclusion criteria (58 exclusions). Postoperative PROMIS-PF (45.6), PROMIS-PI (54.6), and PROMIS-D (44.1) significantly improved at least 3 months after surgery when compared with baseline (P = .002). MCID values for PROMIS-PF, PROMIS-PI, and PROMIS-D were 3.5, 3.3, and 4.4, respectively. Individuals with PROMIS-PF scores below 34.9 yielded an 82% probability of achieving MCID, while PROMIS-PI scores above 67.5 yielded an 86% probability of achieving MCID and a cutoff of 58.9 for PROMIS-D yielded a 60% probability of achieving MCID, with 90% specificity.

CONCLUSIONS

PROMIS scores, obtained preoperatively, were shown to be valid predictors of postoperative clinical improvement in patients undergoing meniscectomy. Our findings suggest that patients with physical function scores of 34.9 or less have an increased probability of reaching a minimal clinically important difference. Similarly, patients with pain interference scores of 67.5 and above have increased probability of reaching MCID for pain interference. These cutoffs may be used by physicians to aid in the counseling of patients considering arthroscopic meniscectomy.

LEVEL OF EVIDENCE

IV, Case Series.

Preliminary Results From a US Clinical Trial of a Novel Synthetic Polymer Meniscal Implant

Background:

At least 760,000 outpatient meniscectomies are performed in the United States each year, making this the most common musculoskeletal procedure. However, meniscal resection can alter the joint biomechanics and overload the articular cartilage, which may contribute to degenerative changes and the need for knee replacement. Avoiding or delaying knee replacement is particularly important in younger or more active patients. Synthetic meniscal implants have been developed in an attempt to restore the natural joint biomechanics, alleviate pain and disability, and potentially minimize degenerative changes in patients who require meniscectomy.

Purpose

To evaluate the preliminary results from 2 ongoing trials that are evaluating the safety and effectiveness of a synthetic polymer meniscal implant (NUsurface; Active Implants, LLC).

Study Design:

Cohort study; Level of evidence, 2.

Methods:

This was a preliminary analysis of the first 100 patients enrolled across 2 studies for 12 months: a single-arm, intervention-only study and a randomized controlled trial comparing the investigational meniscal implant with nonsurgical therapy. There were 65 patients in the implant group (30 randomized) and 35 in the control group. Outcomes included Knee injury and Osteoarthritis Outcome Score (KOOS) and adverse events (AEs) collected at baseline and follow-up visits of 6 weeks, 6 months, and 12 months.

Results:

No statistically significant differences were found in baseline characteristics between the implant and control groups. At 12 months, follow-up KOOS data were available for 87% of the 100 included patients. Significantly greater improvements from baseline were observed in the implant group compared with controls in all KOOS subcomponents, except for symptoms (119%-177% greater improvement at 12 months). AEs were reported at similar rates between the 2 groups, with 12 AEs among 11 patients in the implant group (16.9%) versus 5 AEs among 5 patients (14.3%) in the control group (P = .99).

Conclusion:

These preliminary results suggest significant improvements in pain and function scores with the implant over nonsurgical therapy and a similar adverse event rate.

Cartilage degeneration post-meniscectomy performed for degenerative disease versus trauma: data from the Osteoarthritis Initiative

OBJECTIVE

To compare the extent of cartilage deterioration in knees with prior meniscal resection related to trauma versus knees with resection related to degenerative disease, and to compare cartilage deterioration in knees with meniscal surgery to knees without meniscal surgery, controlling for prior knee trauma.

MATERIALS AND METHODS

In this cross-sectional study, we assessed cartilage deterioration in right knees of Osteoarthritis Initiative participants: (i) with meniscal surgery due to injury (n = 79); (ii) matched control knees with a prior injury but without meniscal surgery (n = 79); (iii) with meniscal surgery but without preceding injury (n = 36); and (iv) matched control knees without meniscal surgery or prior knee injury (n = 36). Cartilage composition was measured using T2 measurements derived using semi-automatic cartilage segmentation of the right. Linear regression analysis was used to compare compartmental values of T2 between groups.

RESULTS

Comparing the mean T2 values in surgical cases with and without injury our results did not show significant differences (group i vs. iii, p > 0.05). However, knees with previous meniscal surgery showed significantly (p < 0.001) higher mean T2 values across all compartments (i.e., global T2) when compared to those without meniscal surgery for both knees with a history of trauma (group i vs. ii) and knees without prior trauma (group iii vs. iv). Similar results were obtained when analyzing the compartments separately.

CONCLUSIONS

Cartilage deterioration, assessed by T2, is similar in knees undergoing meniscal surgery after trauma and for degenerative conditions. Both groups demonstrated greater cartilage deterioration than nonsurgical knees, controlling for prior knee injury.

Knee Arthroscopic Surgery in Middle-Aged Patients With Meniscal Symptoms: A 5-Year Follow-up of a Prospective, Randomized Study

Background:

Arthroscopic meniscal surgery is a common orthopaedic procedure in middle-aged patients, but the efficacy of this procedure has been questioned. In this study, we followed up the only randomized controlled trial that has shown a 1-year benefit from knee arthroscopic surgery with an exercise program compared with an exercise program alone.

Purpose:

To (1) evaluate whether knee arthroscopic surgery combined with an exercise program provided an additional 5-year benefit compared with an exercise program alone in middle-aged patients with meniscal symptoms, (2) determine whether baseline mechanical symptoms affected the outcome, and (3) compare radiographic changes between treatment groups.

Study Design:

Randomized controlled trial; Level of evidence, 1.

Methods:

Of 179 eligible patients aged 45 to 64 years, 150 were randomized to either a 3-month exercise program (nonsurgery group) or to the same exercise program plus knee arthroscopic surgery (surgery group) within 4 weeks. Radiographs were assessed, according to the Kellgren-Lawrence grade, at baseline and at the 5-year follow-up. The primary outcome was the change in Knee injury and Osteoarthritis Outcome Score (KOOS)–Pain (KOOS_PAIN) subscore from baseline to the 5-year follow-up. We performed an as-treated analysis.

Results:

A total of 102 patients completed the 5-year questionnaire. At the 5-year follow-up, both groups had significant improvement in KOOS_PAIN subscores, although there was no significant change from the 3-year scores. There was no between-group difference in the change in the KOOS_PAIN subscore from baseline to 5 years (3.2 points [95% CI, –6.1 to 12.4]; adjusted P = .403). In the surgery group, improvement was greater in patients without mechanical symptoms than in those with mechanical symptoms (mean difference, 18.4 points [95% CI, 8.7 to 28.1]; P < .001). Radiographic deterioration occurred in 60% of patients in the surgery group and 37% of those in the nonsurgery group (P = .060).

Conclusion:

Knee arthroscopic surgery combined with an exercise program provided no additional long-term benefit after 5 years compared with the exercise program alone in middle-aged patients with meniscal symptoms. Surgical outcomes were better in patients without mechanical symptoms than in patients with mechanical symptoms during the preoperative period. Radiographic changes did not differ between treatment groups.

Registration:

NCT01288768 (ClinicalTrials.gov identifier).

Tibiofemoral Contact Mechanics With Horizontal Cleavage Tears and Treatment of the Lateral Meniscus in the Human Knee: An In Vitro Cadaver Study

BACKGROUND

Partial meniscectomy is one of the most commonly performed orthopaedic procedures for a meniscus tear. Decreased contact area and increased contact pressure have been seen in partial meniscectomies from treatment of various types of meniscal tears; however, the biomechanical effect of a horizontal cleavage tear in the lateral meniscus and subsequent treatment are unknown.

QUESTIONS/PURPOSES

This study asked whether a horizontal cleavage tear of the lateral meniscus, resecting the inferior leaf, and further resecting the superior leaf would (1) decrease contact area and (2) increase peak contact pressure.

METHODS

Eleven fresh-frozen human cadaveric knees were evaluated under five conditions of intact meniscus, horizontal cleavage tear, inferior leaf resection, and resection of the inferior and superior leaves of the lateral meniscus. Tibiofemoral contact area and pressure were measured at 0° and 60° knee flexion under an 800-N load, normalized to that at the intact condition of the corresponding knee flexion, and compared across the five previously described conditions.

RESULTS

At 0° knee flexion, normalized contact area with inferior leaf resection (65.4% ± 14.1%) was smaller than that at the intact condition (100% ± 0.0%, p < 0.001); smaller than horizontal cleavage tear (94.1% ± 5.8%, p = 0.001) contact area; and smaller than repaired horizontal tear (92.8% ± 8.2%, p = 0.001) contact area. Normalized contact area with further superior leaf resection (50.5% ± 7.3%) was smaller than that at the intact condition (100% ± 0.0%, p < 0.001); smaller than horizontal cleavage tear (94.1% ± 5.8%, p < 0.001) contact area; and smaller than repaired horizontal tear (92.8% ± 8.2%, p < 0.001) contact area. At 60° flexion, normalized contact area with inferior leaf resection (76.1% ± 14.8%) was smaller than that at the intact condition (100% ± 0.0%, p = 0.004); smaller than horizontal cleavage tear (101.8% ± 7.2%, p = 0.006) contact area; and smaller than repaired horizontal tear (104.0% ± 13.3%, p < 0.001) contact area. Normalized contact area with further superior leaf resection (52.1% ± 16.7%) was smaller than that at the intact condition (100% ± 0.0%, p < 0.001); smaller than horizontal cleavage tear (101.8% ± 7.2%, p < 0.001) contact area; and smaller than repaired horizontal tear (104.0% ± 13.3%, p < 0.001) contact area. At 60° flexion, contact area with both leaf resection (52.1% ± 16.7%) was smaller than that with inferior leaf resection (76.1% ± 14.8%, p = 0.039). At 0° knee flexion, peak pressure increased to 127.0% ± 22.1% with inferior leaf resection (p = 0.026) and to 138.6% ± 24.3% with further superior leaf resection (p = 0.002) compared with that at the intact condition (100% ± 0.0%). At 60° flexion, compared with that at the intact condition (100% ± 0.0%), peak pressure increased to 139% ± 33.6% with inferior leaf resection (p = 0.035) and to 155.5% ± 34.7% (p = 0.004) with further superior leaf resection.

CONCLUSIONS

Resection of the inferior leaf or both leaves of the lateral meniscus after a horizontal cleavage tear resulted in decreased contact area and increased peak contact pressure at 0° and 60° knee flexion.

CLINICAL RELEVANCE

In vitro resection of one or both leaves of a horizontal cleavage tear of the lateral meniscus causes increases in peak pressure, consistent with other types of partial meniscectomies associated in a clinical setting with excessive loading and damage to knee cartilage. Clinical outcomes in patients undergoing partial leaf meniscectomy could confirm this theory. Avoidance of resection may be relatively beneficial for long-term function. The findings of this in vitro study lend biomechanical support for nonoperative management.