Open meniscal repair: clinical and magnetic resonance imaging findings after twelve years

Do MRI Results Represent Functional Outcomes Following Arthroscopic Repair of an Isolated Meniscus Tear in Young Patients?-A Prospective Comparative Cohort Study

BACKGROUND

The use of postoperative MRI to assess the healing status of repaired menisci is a long-standing issue. This study evaluates and compares functional and MRI outcomes following an arthroscopic meniscus repair procedure with the aim of postoperative MRI diagnostic accuracy clarification in young patients.

METHODS

A total of 35 patients under 18 years old who underwent isolated meniscus repair were included. The Pedi-IKDC score, Lysholm score, and Tegner activity index (TAS) were compared between the groups formed according to the Stroller and Crues three-grade classification of postoperative MRI-based evaluations. Grade 3 MRI views were classified as unhealed, grade 2 as partially healed, and grade 1 as fully healed within the repaired meniscus, whereas grade 3 cases were considered unsuccessful due to MRI evaluation.

RESULTS

MRI assessment revealed 4 cases of grade 1 (11.4%), 14 cases of grade 2 (40.8%), and 17 cases of grade 3 (48.0%) lesions. Pedi-IKDC and TAS scores were significantly higher among MRI grade 2 patients than among MRI grade 3 patients (p < 0.05). Weak negative correlations between MRI grades and all functional scales were found (p < 0.05). ROC analysis showed that Pedi-IKDC and TAS scores could correctly classify 77% and 71% of MRI grade 3 patients, respectively. The optimal cut-off values to detect grade 3 patients were 88.74 for the Pedi-IKDC score and 4.5 for the TAS score.

CONCLUSIONS

To conclude, established functional score cut-off values may help identify unhealed meniscus repair patients.

MRI Criteria for Healing at 1 Year After Repair of a Traumatic Meniscal Tear

BACKGROUND

Meniscal repair for a traumatic meniscal tear is increasingly used to preserve the meniscus. Interpreting postoperative magnetic resonance imaging (MRI) scans remains challenging, especially in symptomatic patients. There is a lack of reliable MRI criteria to affirm the healed character of a traumatic meniscal injury repair.

PURPOSE

To identify relevant MRI criteria for meniscal healing after meniscal repair.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

We prospectively included all patients with a traumatic meniscal injury who underwent either an isolated meniscal repair or a repair during a concomitant anterior cruciate ligament reconstruction. A standardized preoperative and postoperative clinical evaluation was performed, along with collection of functional scores-Knee injury and Osteoarthritis Outcome Score, International Knee Documentation Committee, Lysholm Score, and 36-Item Short Form Health Survey. An MRI scan was performed 1 year postoperatively and compared with the preoperative MRI scan. The following MRI aspects were analyzed: variation of morphology and fat-saturated (FS) T2 intensity signal and pre- and postoperative tear diastasis measurement.

RESULTS

Fifty patients (age, mean ± SD, 28.7 ± 8.5 years [range, 16-45 years]) who were 1 year postoperative were included. All patients were considered clinically healed had the same MRI characteristics. A signal change (FS T2) was observed from a high signal intensity fluid to a nonfluid moderate signal intensity. The morphology of the lesion was more complex: from the initial lesion, line ramifications appeared, creating the appearance of tree branches. The tear diastasis decreased (from 2.3 ± 0.5 mm [range, 1.3-3.5] to 1.1 ± 0.28 mm [range, 0.5-1.5]).

CONCLUSION

MRI criteria confirming meniscal healing after traumatic meniscal repair at 1 year were identified: a change in the intrameniscal signal becoming nonfluid and moderate in intensity; a reduction in tear diastasis to <1.5 mm; and a change in the signal morphology of the repaired meniscus.

A highly elastic absorbable monofilament suture fabricated from poly(3-hydroxybutyrate-co-4-hydroxybutyrate)

To address the growing demand for more elastic sutures free from unwanted knot loosening, we fabricated an absorbable monofilament suture from poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and subjected it to physical property characterization and performance evaluation (in vitro and in vivo degradability tests and a porcine abdominal wall suture test). As this flexible, highly stretchable, and difficult-to-untie suture exhibited additional advantages of small knot size and medium to long-term bioabsorbability, it was concluded to be a safe alternative to existing monofilament sutures, with far-reaching potential applications.

[The postoperative knee : Common complications and their correct diagnosis]

BACKGROUND

Injuries of the knee are common, with torn meniscus and anterior cruciate ligament tears being among the pathologies most commonly treated by surgery.

OBJECTIVES

To review the various normal and pathological postoperative magnetic resonance imaging (MRI) findings following anterior cruciate ligament reconstruction or meniscus surgery.

MATERIALS AND METHODS

Evaluation of clinical trials and expert opinions.

RESULTS

After knee surgery, various complications (e.g., inadequate tunnel placement, impingement, arthrofibrosis, graft disruption, and recurrent meniscus tear) have been described. These can usually be reliably diagnosed if the timing and type of surgery are known; however, limitations for imaging must also be considered.

CONCLUSIONS

Interpretation of postoperative knee MRI is challenging and requires knowledge of common complications of each type of surgery and their normal postoperative appearance on MRI.

Arthroscopic meniscus repair and augmentation with autologous fibrin clot in Indian population: A 2-year prospective study

INTRODUCTION

This study was proposed to evaluate the efficacy of fibrin clot augmentation in meniscal tear using inside-out meniscal repair.

METHODS

A total of 35 patients with meniscus tears were operated on with inside-out meniscus repair and fibrin clot augmentation. Patients were evaluated preoperatively and postoperatively with clinical criteria, Lysholm knee scoring system, and MRI.

RESULTS

Out of the total 35 cases, 5 cases were lost to follow-up. Clinical improvement was observed in 29 out of 30 patients (96.6%). The mean Lysholm score improved significantly from 67.63 ± 6.55 points preoperatively to 92.0 ± 2.9 points postoperatively (P < 0.05) in 3 years follow-up. Follow-up MRI in all patients revealed complete healing except in 1 case where the patient presented with recurrence of symptoms such as pain and locking which resolved with partial meniscectomy. Paraesthesia in the anterior part of the knee was observed in 2 cases. (6.6%).

CONCLUSION

We conclude that fibrin clot augmentation is a good cost-effective modality of treatment for repairable meniscus tears to preserve the meniscus and decrease the point contact pressure on the condyles which may prevent the early occurrence of osteoarthritis.

Meniscal Repair Outcomes at Greater Than 5 Years: A Systematic Review and Meta-Analysis

BACKGROUND

The utilization of meniscal repair techniques continues to evolve in an effort to maximize the rate of healing. Meniscal repair outcomes at a minimum of 5 years postoperatively appear to better represent the true failure rates. Thus, a systematic review and meta-analysis of the current literature was conducted to assess the rate of failure at a minimum of 5 years after meniscal repair.

METHODS

We performed a systematic review of studies reporting the outcomes of meniscal repair at a minimum of 5 years postoperatively. A standardized search and review strategy was utilized. Failure was defined as recurrent clinical symptoms or a meniscal reintervention to repair or resect the meniscus in any capacity, as defined by the study. When reported, outcomes were assessed relative to anterior cruciate ligament (ACL) status, sex, age, and postoperative rehabilitation protocol. Meta-analyses were performed with a random-effects model.

RESULTS

A total of 27 studies of 1,612 patients and 1,630 meniscal repairs were included in this review and meta-analysis. The pooled overall failure rate was 22.6%, while the failure rate of modern repairs (excluding early-generation all-inside devices) was 19.5%. Medial repairs were significantly more likely to fail compared with lateral repairs (23.9% versus 12.6%, p = 0.04). Failure rates were similar for inside-out (14.2%) and modern all-inside repairs (15.8%). Early-generation all-inside devices had a significantly higher failure rate (30.2%) compared with modern all-inside devices (15.8%, p = 0.01). There was no significant difference in meniscal failure rate between repairs with concomitant ACL reconstruction (21.2%) and repairs in ACL-intact knees (23.3%, p = 0.54).

CONCLUSIONS

Modern meniscal repair had an overall failure rate of 19.5% at a minimum of 5 years postoperatively. Modern all-inside techniques appear to have improved the success rate of meniscal repair compared with use of early-generation all-inside devices. Lateral repairs were significantly more likely to be successful compared with medial repairs, while no difference was seen between patients undergoing meniscal repair with and without concomitant ACL reconstruction.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A systematic review about long-term results after meniscus repair

PURPOSE

Aim of this systematic review was to analyze long-term results after meniscus refixation.

METHODS

A systematic literature search was carried out in various databases on studies on long-term results after meniscus refixation with a minimum follow-up of 7 years. Primary outcome criterion was the failure rate. Secondary outcome criteria were radiological signs of osteoarthritis (OA) and clinical scores.

RESULTS

A total of 12 retrospective case series (level 4 evidence) were identified that reported about failure rates of more than 7 years follow-up. There was no statistical difference in the failure rates between open repair, arthroscopic inside-out with posterior incisions and arthroscopic all-inside repair with flexible non-resorbable implants. In long-term studies that examined meniscal repair in children and adolescents, failure rates were significantly higher than in studies that examined adults. Six studies have shown minor radiological degenerative changes that differ little from the opposite side. The reported clinical scores at follow-up were good to very good.

CONCLUSION

This systematic review demonstrates that good long-term outcomes can be obtained in patients after isolated meniscal repair and in combination with ACL reconstruction. With regard to the chondroprotective effect of meniscus repair, the long-term failure rate is acceptable.

LEVEL OF EVIDENCE

IV.

Excellent medium-term survival of an all-inside tensionable knotted suture device justifies repair of most meniscal tears encountered during reconstructive knee ligament surgery

PURPOSE

All-inside meniscal repair devices have evolved to allow surgeons to undertake complex repairs in a timely and efficient manner. This is advantageous in active patients, where meniscus preservation is critical in preserving joint function and stability. The aim of the study was to evaluate the failure rate of all-inside meniscal repair performed in patients undergoing reconstructive ligament surgery using a particular meniscal repair device.

METHODS

Patients were identified using a single-site prospectively maintained patient registry. Primary outcome was failure, defined as return to surgery with documented failure of repair. Complication rates and functional scores were also recorded. Patients in whom meniscal repair failure was identified were further assessed, to identify any common features.

RESULTS

Over an 8-year period, 323 patients underwent meniscal repair at the time of ligament reconstruction, compared to 244 meniscectomies. Of these, 286 patients underwent repair using an all-inside suture device. One-hundred and twenty-seven repairs were to the medial meniscus only, 124 were lateral, and in 35 patients both menisci were repaired. Follow-up was to a median of 51.5 months. There were 31 (9.7%) failures reported at a median of 22 months post-operatively (IQR 13.5-41.5). Medial repair failures were seen more frequently than lateral (13.6% versus 5.6% OR 2.62 95% CI 1.17-5.88 p = 0.022). Failure of ACL reconstruction was associated with meniscal repair failure (OR 5.83 95% CI 1.55-21.95 p = 0.0039). Multi-ligament reconstruction was undertaken in 70/286 patients receiving meniscal repair and was not associated with failure (OR 1.3 95% CI 0.57-2.98 p = 0.51). Mode number of all-inside sutures used was 3 in both medial and lateral repairs (Range 1-9 lateral; 1-7 medial).

CONCLUSIONS

All-inside repair is a safe and versatile technique which can be used in the majority of meniscal tears encountered during ligament reconstruction with excellent mid-term success. Failure is seen more commonly in medial sided repairs and with failure of ACL reconstruction.

LEVEL OF EVIDENCE

IV.

Magnetic resonance imaging can increase the diagnostic accuracy in symptomatic meniscal repair patients

PURPOSE

The purpose of this study was to evaluate meniscal repair healing in symptomatic patients through combined clinical assessment, magnetic resonance imaging (MRI) and re-arthroscopy. This study investigated the diagnostic accuracy of MRI and clinical assessment in determining failed meniscal repair in symptomatic meniscal repair patients, as verified by re-arthroscopy.

METHODS

Eighty patients were included. All had undergone a primary meniscal repair followed by an MRI and re-arthroscopy due to clinical symptoms of a meniscal lesion. A validated semi-quantitative scoring system was employed for identifying MRI-diagnosed healing failure. The clinical assessment was divided into joint swelling, joint-line tenderness, locking and a positive McMurray's test. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of MRI and positive clinical findings were calculated using second-look arthroscopy as a standard.

RESULTS

The MRI results showed healing of 22 (27.5%) of the menisci and 58 (72.5%) unhealed menisci, whereas second-look arthroscopy identified 15 (19%) healed menisci and 65 (81%) unhealed menisci. The isolated MRI findings were 0.85, 0.8, 0.95 and 0.55 for sensitivity, specificity, PPV and NPV, respectively. The PPVs of the clinical assessments were 0.78, 0.85 and 0.94, with one, two and three clinical findings, respectively. A grade 3 MRI combined with joint-line tenderness presented a PPV of 0.98.

CONCLUSION

A supplementary MRI will increase diagnostic accuracy when fewer than three clinical findings are present in a symptomatic meniscal repair patient. The clinical relevance of this finding is that MRI contributes to enhancing the diagnostic accuracy of an unhealed meniscal repair when there are limited clinical signs of meniscal pathology.

LEVEL OF EVIDENCE

III.

Arthroscopic all-inside repair with suture hook for horizontal tear of the lateral meniscus at the popliteal hiatus region: a preliminary report

Background

Arthroscopic surgery procedures vary depending on the types of meniscus tear, including meniscectomy and meniscus repair. Among the several types of meniscus tear, the horizontal tear of the lateral meniscus at the popliteal hiatus region is a common injury, and its surgical treatment is still inconsistent.

Methods

Between January 2018 and October 2018, 20 patients who underwent all-inside repair with suture hook for the horizontal tear of the lateral meniscus at the popliteal hiatus region were recruited. Any operative complication was recorded, and postoperative MRI scans were conducted at the 6 months. The clinical results were graded based on the scale of the Lysholm knee score preoperatively and at follow-up.

Results

No operative complications were recorded. Postoperative MRIs at the 6 months showed that there was no re-tear for all patients, though signal intensity remained high in T2-weighted MRI in the lateral meniscus for nine cases. The average preoperative Lysholm knee score was 58.6 ± 10.1, which increased significantly to 89.3 ± 7.8 (t = − 11.01, p = 0.001) at the last follow-up. Recurrence or aggravation of symptoms was not noted at the final follow-up.

Conclusion

All-inside repair with suture hook may be a good option for the horizontal tear of the lateral meniscus at the popliteal hiatus region which preserves the meniscus; avoids iatrogenic injury on the adjacent popliteal tendon, common peroneal nerve, and inferior lateral geniculate artery.

Management of traumatic meniscus tears: the 2019 ESSKA meniscus consensus

PURPOSE

The importance of meniscus integrity in the prevention of early osteoarthritis is well known, and preservation is accepted as the primary goal. The purpose of the ESSKA (European Society for Sports Traumatology, Knee Surgery and Arthroscopy) European consensus on traumatic meniscus tears was to provide recommendations for the treatment of meniscus tears based on both scientific evidence and the clinical experience of knee experts.

METHODS

Three groups of surgeons and scientists elaborated and ratified the so-called formal consensus process to define the recommendations for the management of traumatic meniscus tears. A traumatic meniscus tear was defined as a tear with an acute onset of symptoms caused by a sufficient trauma. The expert groups included a steering group of eight European surgeons and scientists, a rating group of another nineteen European surgeons, and a peer review group. The steering group prepared twenty-seven question and answer sets based on the scientific literature. The quality of the answers received grades of A (a high level of scientific support), B (scientific presumption), C (a low level of scientific support) or D (expert opinion). These question and answer sets were then submitted to and evaluated by the rating group. All answers were scored from 1 (= totally inappropriate) to 9 (= totally appropriate) points. Thereafter, the comments of the members of the rating group were incorporated by the steering group and the consensus was submitted to the rating group a second time. Once a general consensus was reached between the steering and rating groups, the finalized question and answer sets were submitted for final review by the peer review group composed of representatives of the ESSKA-affiliated national societies. Eighteen representatives replied.

RESULTS

The review of the literature revealed a rather low scientific quality of studies examining the treatment of traumatic meniscus tears. Of the 27 questions, only one question received a grade of A (a high level of scientific support), and another received a grade of B (scientific presumption). The remaining questions received grades of C and D. The mean rating of all questions by the rating group was 8.2 (95% confidence interval 8.1-8.4). A general agreement that MRI should be performed on a systematic basis was not achieved. However, MRI was recommended when arthroscopy would be considered to identify concomitant pathologies. In this case, the indication for MRI should be determined by a musculoskeletal specialist. Based on our data, stable left in situ lateral meniscus tears appear to show a better prognosis than medial tears. When repair is required, surgery should be performed as early as possible. Evidence that biological enhancement such as needling or the application of platelet-rich plasma would improve healing was not identified. Preservation of the meniscus should be considered as the first line of treatment because of an inferior clinical and radiological long-term outcome after partial meniscectomy compared to meniscus repair.

DISCUSSION

The consensus was generated to present the best possible recommendations for the treatment of traumatic meniscus tears and provides some groundwork for a clinical decision-making process regarding the treatment of meniscus tears. Preservation of the meniscus should be the first line of treatment when possible, because the clinical and radiological long-term outcomes are worse after partial meniscectomy than after meniscus preservation. The consensus clearly states that numerous meniscus tears that were considered irreparable should be repaired, e.g., older tears, tears in obese patients, long tears, etc. LEVEL OF EVIDENCE: II.

3D-MRI combined with signal-to-noise ratio measurement can improve the diagnostic accuracy and sensitivity in evaluating meniscal healing status after meniscal repair

PURPOSE

This study compared the diagnostic accuracy of second-look arthroscopy, clinical assessment, and magnetic resonance imaging (MRI) in evaluating meniscal healing following repair. To explore the application of 3D-MRI sequences with signal-to-noise ratio (SNR) measurements and the analysis of sensitivity and accuracy in evaluating meniscal healing status after meniscal repair.

METHODS

This study included 75 patients (75 menisci; mean age, 25.4 ± 6.6 years) who underwent arthroscopic meniscal repair (medial menisci, 45; and lateral menisci, 29). Follow-up evaluation included clinical assessment, magnetic resonance imaging (MRI), and second-look arthroscopy (mean follow-up, 10.2 ± 3.4 months). The criteria defined for unhealed menisci were: on arthroscopy, presence of cleft; on clinical assessment, presence of joint-line tenderness, swelling, locking, or positive McMurray test; on MRI, grade III signal intensity at the site of repair. Finally, the SNR on 3D-MRI of the healed and the unhealed groups were compared.

RESULTS

On second-look arthroscopy, 68 (90.7%) menisci were found to be completely healed. With the arthroscopic healing rate as the standard, the clinical healing rate was 69.3% (63 menisci) [sensitivity, 85.7%; specificity, 75.0%; accuracy, 76.0%; positive predictive value (PPV), 26.1%; negative predictive value (NPV), 98.1%]. Similarly, the sensitivity, specificity, accuracy, PPV and NPV, respectively, for MRI in four sequences were as follows: 2D-T2W-Sag: 71.4, 79.4, 78.7, 26.3, and 96.4%; 2D-T2W-Cor: 71.4, 82.4, 81.3, 29.4, and 96.6%; 3D-PDW-Sag: 100.0, 50.0, 54.7, 17.1, and 100.0%; 3D-PDW-Cor: 100.0, 58.8, 62.7, 20.0, and 100.0%. The mean SNRs of the healed group (3D-PDW-Sag, 66.7 ± 11.9; 3D-PDW-Cor, 63.9 ± 12.4) were significantly lesser than that of the unhealed group (3D-PDW-Sag, 89.2 ± 9.6; 3D-PDW-Cor, 82.2 ± 18.5) (P < 0.05). Identifying grade 3 meniscal damage on 3D-PDW images prior to applying the different SNR cut-off points revealed SNR values 80 in the sagittal plane and 70 in the coronal plane as having better diagnostic accuracy and sensitivity. The clinical relevance of the study was that 3D-MRI combined with SNR measurement may be a noninvasive and accurate method of assessment clinically, and a reliable alternative to second-look arthroscopy.

LEVEL OF EVIDENCE

III.

Current concepts in the techniques, indications and outcomes of meniscal repairs

Knee arthroscopy for meniscal tears is one of the most commonly performed orthopaedic procedures. In recent years, there has been an increasing incidence of meniscal repairs, as there are concerns that meniscectomy predisposes patients to early osteoarthritis. Indications for meniscal repair are increasing and can now be performed in older patients who are active, even if the tear is in the avascular zone. Options for meniscal tear management broadly fall into three categories: non-operative management, meniscal repair or meniscectomy. With limited evidence directly comparing each of these options optimal management strategies can be difficult. Decision making requires thorough assessment of patient factors (e.g. age and comorbidities) and tear characteristics (e.g. location and reducibility). The purpose of this paper is, therefore, to review the management options of meniscal tears and summarize the evidence for meniscal tear repair.

Are Outcomes After Meniscal Repair Age Dependent? A Systematic Review

PURPOSE

To determine if the failure rate and functional outcome after arthroscopic meniscus suture repair are age dependent.

METHODS

A systematic review was conducted using a computerized search of the electronic databases MEDLINE and ScienceDirect in adherence with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Extracted data from each included study were recorded on a standardized form. Studies were included if they (1) were English-language studies in peer-reviewed journals, (2) used a distinct age cut-off to evaluate outcome of meniscal surgery for those above and below the specified cut-off, and (3) used meniscal repairs using suture based technique with inside-out, outside-in, or all-inside techniques. Review papers, case reports, technique papers, non-English language publications, abstracts, and data on meniscal repairs using meniscal screws, arrows, or darts were excluded.

RESULTS

15 of 305 identified articles met the inclusion/exclusion criteria. There were 1,141 menisci treated in 1,063 patients. Seven and 8 studies met the inclusion/exclusion criteria for analysis for the age thresholds of 25 years and 30 years, respectively, demonstrating no difference in failure rates relative to age threshold. Four of 6 studies that met analysis criteria found no difference in failure rates above or below an age threshold of 35 years. No significant difference in failure in patients younger than 40 than patients older than 40 was found for 4 of the 5 studies in that arm of the review.

CONCLUSIONS

Analysis of the composite data in this systematic review reveals that no significant difference exists when evaluating meniscal repair failure rate as a function of age above or below the given age thresholds.

LEVEL OF EVIDENCE

Level IV, systematic review of level III and IV studies.

Analysis of short and long-term results of horizontal meniscal tears in young adults

INTRODUCTION

Symptomatic horizontal meniscal tears are rare but worrisome lesions in young adults. These are overuse injuries not amenable to the classic arthroscopic sutures. An open meniscal repair allows the meniscal lesion to be suture vertically, perpendicular to its in the vascularized zone. The purpose of this study was to evaluate the short and long-term clinical and radiological outcomes of the aforementioned surgical technique.

MATERIAL AND METHOD

The first cohort consisted of 24 patients operated between 2009 and 2011 (6 women, 18 men; mean age 26years) having 11 lateral and 13 medial meniscal tears. The second cohort was of 10 patients operated between 2001 and 2002 (3 women, 7 men; mean age 24years) having 8 lateral and 2 medial meniscal tears. Patients were reviewed at the last follow-up using the IKDC, Lysholm and KOOS scores. Patients in the first cohort had an MRI, while those in the second cohort had X-rays.

RESULTS

Eighteen patients in the first cohort were reviewed with a mean follow-up of 2 years (12-45 months) and 9 patients from the second cohort were reviewed after 10years (97-142 months). In the first cohort, one patient required secondary menisectomy. The mean Lysholm score was 90 and the subjective IKDC was 85. Every MRI examination found reduced extent and intensity of the hyperintense signal. In the second cohort, no patients required secondary meniscectomy. Two patients had joint space narrowing (less than 50%) on radiographs. The mean Lysholm score was 99 and the subjective IKDC was 91.

CONCLUSION

Open repair of horizontal meniscal tears in young adults leads to good subjective and objective results in the short term, which are maintained in the long-term.

LEVEL OF EVIDENCE

Level IV - retrospective study.

Quantitative Ultrashort Echo Time Magnetic Resonance Imaging Evaluation of Postoperative Menisci: a Pilot Study

BACKGROUND

Magnetic resonance imaging (MRI) visualization of meniscal signal is particularly challenging as the highly organized ultrastructure of meniscal fibrocartilage yields very short T2 values (∼6 ms) and a paucity of signal intensity during conventional image acquisition.

QUESTION/PURPOSE

The purpose of this study was to evaluate the feasibility of imaging postoperative menisci using an experimental, quantitative ultrashort echo time (UTE) MRI pulse sequence. This sequence acquires short echo images (echo time (TE) ∼0.3 ms) to produce multi-echo images for quantitative T2* calculations that provide an objective measure of collagen organization.

PATIENTS AND METHODS

MRI scans of the knee were acquired at 6- and 12-month intervals on a clinical 3.0 T scanner following meniscal surgery in eight patients (ages 13-41), four of whom underwent repair and the other four partial meniscectomy. Conventional MRI sequences were qualitatively evaluated for meniscal morphology and signal and correlated with quantitative UTE results.

RESULTS

A wide range of mean T2* values for both postsurgical groups was measured, and these values changed for each patient between the 6- and 12-month intervals. In many instances, the UTE sequence demonstrated quantitative differences between the two time intervals that were not detected with conventional sequences.

CONCLUSIONS

This pilot study presents preliminary, observational data to be used as a baseline for future studies. Although the T2* values did not reveal a trend in either group or correlate with expected signal changes on conventional MRI, we speculate that the UTE sequence may detect ultrastructural alterations in meniscal composition that are otherwise not perceived with routine fast spin echo (FSE) sequences.

All-inside meniscal repair surgery: factors affecting the outcome

Background

Meniscal injury is currently a well-recognized source of knee dysfunction. While it would be ideal to repair all meniscus tears, the failure rate is significantly high, although it may be reduced by careful selection of the patients. Our objective was to assess the outcome of meniscal repair surgery and the role of simultaneous reconstruction of the anterior cruciate ligament (ACL).

Materials and methods

Retrospectively, all consecutive patients between January 2008 and 2011 who underwent meniscal repair were included. Patients were identified using the hospital database with diagnosis and procedure codes. Patient notes were reviewed, including details of the type of tear, chronicity, location, and surgery. We used symptomatic resolution as the outcome measure.

Results

136 Meniscal repairs were performed in 122 patients with a mean age of 26.8 years. Mean follow-up duration was 9 months. 63 % of the patients underwent medial and 37 % underwent lateral meniscal repair, with failure rates of 19 % for medial and 12 % for lateral menisci. Ligament injuries were found in 61 % of the patients (n = 83). Failure of meniscal repair occurred in 14.5 % (n = 12) of the patients who had early ACL reconstruction and in 27 % (n = 22) of the patients who had delayed ACL reconstruction (p = 0.0006). The failure rate was found to be 13 % in patients who were younger than 25 years (61 %) and 15 % in patients who were older than 25 years (39 %).

Conclusion

The success rate of meniscal repair was found to be significantly better when ACL reconstruction was performed simultaneously with meniscal repair.

Level of evidence

Level IV.

Failure of meniscal repair association with late anterior cruciate ligament reconstruction

INTRODUCTION

Meniscus injury is associated with ACL (anterior cruciate ligament) injury. It would be ideal to repair all meniscus tears but failure rate is high.

AIM

Our objective was to assess the success of meniscus repair.

METHOD

All consecutive patients between Jan 2009 to Dec 2013 were retrospectively analysed.

RESULTS

85 meniscus repairs were performed: 64 patients presented after 3 months (Group 1) and 21 patients had meniscus repair within 2 weeks. The failure rate group 1 was 23%-4.8% group 2 at a mean follow up of 11 months.

CONCLUSION

Early meniscal repair had a higher success rate. Level III evidence.

Platelet-rich plasma for open meniscal repair in young patients: any benefit?

PURPOSE

Many studies have demonstrated that injection of various growth factors including platelet-derived growth factor could increase meniscal cell activity and stimulate repair. The purpose of this study was to augment repair and promote meniscal healing by the use of platelet-rich plasma (PRP) within horizontal cleavage meniscal tears repaired via an open approach. The hypothesis was that the clinical outcomes and healing process would be improved using this meniscal healing augmentation technique.

METHODS

In this case-control study, 34 consecutive young patients underwent an open meniscal repair to treat symptomatic Grade 2 or Grade 3 horizontal meniscal tears [median age 28 years (13-40)]. The median time between the onset of symptoms and surgery was 11.5 months (6-50). In the first group (17 consecutive patients, Group 1), a standard open meniscal repair was performed. In the second group (17 consecutive patients, Group 2), the same surgical repair was performed, but platelet-rich plasma was introduced into the lesion at the end of the procedure. Clinical outcomes were evaluated using KOOS and IKDC 2000 scores. MRI was performed at 1 year after surgery for objective evaluation.

RESULTS

At a minimum of 24 months postoperatively (mean 32.2 months, 24-40), three patients underwent subsequent meniscectomy (two in Group 1, one in Group 2). The mean KOOS distribution (pain, symptoms, daily activities, sports, quality of life) was 78.4, 86.1, 93.8, 74.4, 74.6 in Group 1, and 93.3, 90.7, 97.1, 88.8, 78.3 in Group 2 (p < 0.05 for pain and sports parameters). MRI revealed five cases with the complete disappearance of any hypersignal within the repaired meniscus in Group 2, and none in Group 1 (p < 0.01).

CONCLUSIONS

Open meniscal repair of horizontal tears extending into the avascular zone was effective at midterm follow-up in young patients. Clinical outcomes were slightly improved by the addition of PRP in this case-control study.

LEVEL OF EVIDENCE

III.

Long-term outcomes of all-inside meniscal repair

PURPOSE

The mean reported healing rate after meniscal repair is 60% of complete healing, 25% of partial healing and 15% of failure. However, partially or incompletely healed menisci are often asymptomatic in the short term. It is unknown whether the function of the knee with a partially or incompletely healed meniscus is disturbed in the long term. The purpose of this study was to assess the long-term outcomes of meniscal repairs according to the initial rate of healing.

METHODS

Forty-one consecutive meniscal repairs were performed between 2002 and 2003. The median age at the time of surgery was 22 years (9-40). There were 25 medial and 16 lateral menisci. When present, all ACL lesions underwent reconstruction (61.3% of cases). According to Henning's criteria, by Arthro-CT at 6 months, twenty cases had healed completely, seven partially healed and four cases healed incompletely.

RESULTS

At a mean follow-up of 114 ± 10 months, 31 patients were retrospectively followed for clinical and imaging assessments. Objective IKDC score was good in 92% of the cases (17 IKDC A, 8 B and 2 C). The mean KOOS distribution was as follows: pain 94.3 ± 9; symptoms 90.9 ± 15; daily activities 98.7 ± 2; sports activities 91.1 ± 14; and quality of life 91.5 ± 15. Twenty-three patients displayed no signs of osteoarthritis when compared to the non-injured knee, six patients had grade 1 osteoarthritis and two grade 2. The subjective IKDC score did not decrease with time (ns). Moreover, there were no differences between lateral and medial menisci (ns), in stable or stabilised knees (ns). The initial meniscal healing rate did not significantly influence clinical or imaging outcomes (ns). Four patients with no healing underwent a meniscectomy (12.9%).

CONCLUSION

Arthroscopic all-inside meniscal repair with hybrid devices may provide long-term protective effects, even if the initial healing is incomplete.

LEVEL OF EVIDENCE

Case series, Level IV.

The Effect of Perioperative Ketorolac on the Clinical Failure Rate of Meniscal Repair

Background:

There has been recent interest in the effect of nonsteroidal anti-inflammatory medications on musculoskeletal healing. No studies have yet addressed the effect of these medications on meniscal healing.

Hypothesis:

The administration of ketorolac in the perioperative period will result in higher rates of meniscal repair clinical failure.

Study design:

Cohort study; Level of evidence, 3.

Methods:

A total of 110 consecutive patients underwent meniscal repair at our institution between August 1998 and July 2001. Three patients were lost to follow-up, and the remaining 107 (mean age, 15.9 ± 4.4 years) had a minimum 5-year follow-up (mean follow-up, 5.5 years). Thirty-two patients (30%) received ketorolac perioperatively. The primary outcome measure was reoperation for continued symptoms of meniscal pathology. Asymptomatic patients were evaluated by the International Knee Documentation Committee (IKDC) Subjective Knee Form, Short Form–36 (SF-36) Health Survey, and Knee Outcome Osteoarthritis Score (KOOS).

Results:

Kaplan-Meier survivorship revealed no difference in reoperation rates with and without the administration of perioperative ketorolac (P = .95). There was an overall failure rate of 35% (37/107 patients), with a 34% failure rate in patients receiving ketorolac (11/32 patients). Multivariable Cox regression confirmed that age, duration of symptoms, meniscal tear type, fixation technique, concurrent anterior cruciate ligament repair, and ketorolac usage did not have an impact on the rate of failure (P > .05 for all; ketorolac use, P > .50). Female sex (P = .04) and medial location (P = .01) were predictive of an increased risk for reoperation.

Conclusion:

Failure of meniscal repair was not altered with the administration of perioperative ketorolac. Further work studying the effects of longer term anti-inflammatory use after meniscal repair is necessary before stating that this class of medications has no effect on meniscal healing.

Clinical Relevance:

Results of this study suggest that nonsteroidal anti-inflammatory ketorolac can be administered perioperatively during a meniscal repair procedure to harness its benefits of decreased narcotic requirement, decreased pain, and shorter length of hospital stay without negatively influencing the long-term outcome of the surgery.

Free rehabilitation is safe after isolated meniscus repair: a prospective randomized trial comparing free with restricted rehabilitation regimens

BACKGROUND

The optimal rehabilitation program after meniscus repair has not been established. Numerous regimens have been suggested as beneficial for meniscus healing, but no controlled trials exist in the literature.

HYPOTHESIS

The purpose of this prospective randomized trial was to investigate outcome with a free or a restricted rehabilitation regimen after isolated meniscus repair. The hypothesis was that free rehabilitation would result in increased failure of meniscus healing.

STUDY DESIGN

Randomized controlled clinical trial; Level of evidence, 1.

METHODS

A total of 60 patients were included in this study within 2 to 3 days after meniscus repair. No patients with concomitant ligament reconstruction or cartilage repair surgery were included. Meniscus repair was performed with the all-inside technique; only vertical meniscus lesions close to the capsule were repaired. Patients were randomized to free (n = 32) or restricted (n = 28) rehabilitation. Free rehabilitation consisted of 2 weeks (range of motion [ROM], 0°-90°, no brace) and touch weightbearing, with unrestricted activity and free ROM allowed thereafter. Restricted rehabilitation consisted of 6 weeks of hinged brace use with a gradual increase ROM to 90° and only touch weightbearing during the 6 weeks. Patients were seen for follow-up at 3 months, 1 year, and 2 years. Those patients with joint line pain at the 3-month follow-up underwent MRI scanning to evaluate meniscus healing; a subsequent arthroscopy was performed for final evaluation meniscus healing if the MRI indicated lack of meniscus healing. At follow-up, the Knee Osteoarthritis Outcome Score (KOOS), Tegner function score, pain assessment, and patient satisfaction were used to evaluate outcomes.

RESULTS

Eleven patients were lost to follow-up. Repeat arthroscopy in patients with persistent symptoms demonstrated partial healing or lack of healing in 28% and 36% of patients in the free and the restricted rehabilitation groups, respectively (P = .53, nonsignificant). The KOOS and Tegner function scores were similar between groups at all follow-up times, as was patient satisfaction. Patients who underwent subsequent partial meniscectomy because of meniscus repair failure had lower KOOS score and Tegner function score than did patients without repair failure.

CONCLUSION

Free rehabilitation after meniscus repair is safe and does not entail increased failure rates compared with restricted rehabilitation. Subjective and functional outcomes at 1- and 2-year follow-up were not affected by rehabilitation regimen. Clinical outcomes in patients with repair failure who underwent subsequent partial meniscectomy were poorer than in those with healed meniscus repairs. A concern is the 30% overall lack of healing for patients with isolated meniscus lesions repaired with the all-inside technique.

Trends in meniscus repair and meniscectomy in the United States, 2005-2011

BACKGROUND

Meniscus deficiency may lead to degenerative arthritis in the knee. There is a significant emphasis on meniscus preservation, particularly in the young patient, to reduce the risk of arthritis.

PURPOSE

To report on the incidence of meniscus repair and meniscectomy, with and without concomitant anterior cruciate ligament (ACL) reconstruction, in the United States (US) over the past 7 years.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Patients who underwent arthroscopic meniscectomy (Current Procedural Terminology [CPT] codes 29880 and 29881), meniscus repair (CPT codes 29882 and 29883), and ACL reconstruction (CPT code 29888) for the years 2005 through 2011 were identified using the PearlDiver Patient Record Database. Age group and sex were collected for each patient. Patient groups included meniscectomy alone, meniscus repair alone, meniscus repair followed by meniscectomy, ACL reconstruction with concomitant meniscus repair, and ACL reconstruction with concomitant meniscus repair followed by meniscectomy. Linear regression and Student t tests were utilized for comparisons, with an α value of .05 set as significant.

RESULTS

The database represented approximately 9% of the US population under 65 years of age. There was no significant change in the number of patients in the covered population during the study time frame (P = .138). From 2005 to 2011, there were a total of 387,833 meniscectomies, 23,640 meniscus repairs, and 84,927 ACL reconstructions. There was a significant increase in the total number of isolated meniscus repairs performed (P = .001) and a doubling of the incidence of repairs from 2005 to 2011. There was no significant increase in the total number of meniscectomies performed (P = .712), while the incidence of meniscectomies increased only 14% from 2005 to 2011. There was no significant change in the number of meniscus repairs performed at the same time as ACL reconstruction during the study time frame. The total number and incidence of meniscectomies after repair with and without ACL reconstruction significantly decreased.

CONCLUSION

There has been an increased number of isolated meniscus repairs being performed in the US over the past 7 years without a concomitant increase in meniscectomies over the same time frame. These data suggest that meniscus repairs are preferentially being performed over meniscectomies.

Magnetic resonance imaging is not suitable for interpretation of meniscal status ten years after arthroscopic repair

PURPOSE

The purpose of this study was to assess the MRI features of the all-inside repaired meniscus in the long-term.

METHODS

Among 27 consecutive all-inside arthroscopic meniscal repairs, 23 patients aged 25 ± 5 years at the time of surgery were reviewed at a median follow-up of 10 ± 1 years. Retrospective clinical examinations and imaging assessments using a 1.5-T MRI after all-inside arthroscopic meniscal repair were conducted.

RESULTS

At follow-up, Lysholm and IKDC averaged 89 ± 11 and 95 ± 8, respectively. MRI examinations revealed no meniscal signal alteration in three patients (13%), a vertical signal located in the previously torn area in seven (30%), a horizontal grade 3 in nine (39%), and a complex tear (grade 4) in four (17.5%). There were no differences between medial and lateral menisci (p = 0.15), stable and stabilised knees (p = 0.56).

CONCLUSIONS

Several abnormal vertical and/or horizontal hypersignals are still present on MRI examination ten years after arthroscopic all-inside meniscal repair. The appearance of early signs of osteoarthritis is rare, suggesting a chondroprotective effect of the repaired meniscus.

Meniscal repair outcomes at greater than five years: a systematic literature review and meta-analysis

BACKGROUND

Meniscal repair offers the potential to avoid the long-term articular cartilage deterioration that has been shown to result after meniscectomy. Failure of the meniscal repair can occur several years postoperatively. Limited evidence on the long-term outcomes of meniscal repair exists.

METHODS

We performed a systematic review of studies reporting the outcomes of meniscal repair at a minimum of five years postoperatively. Pooling of data and meta-analysis with a random-effects model were performed to evaluate the results.

RESULTS

Thirteen studies met the inclusion criteria. The pooled rate of meniscal repair failure (reoperation or clinical failure) was 23.1% (131 of 566). The pooled rate of failure varied from 20.2% to 24.3% depending on the status of the anterior cruciate ligament (ACL), the meniscus repaired, and the technique utilized. The rate of failure was similar for the medial and the lateral meniscus as well as for patients with an intact and a reconstructed ACL.

CONCLUSIONS

A systematic review of the outcomes of meniscal repair at greater than five years postoperatively demonstrated very similar rates of meniscal failure (22.3% to 24.3%) for all techniques investigated. The outcomes of meniscal repair at greater than five years postoperatively have not yet been reported for modern all-inside repair devices.

Outcome of repaired unstable meniscal tears in children and adolescents

BACKGROUND

Unstable meniscal tears are rare injuries in skeletally immature patients. Loss of a meniscus increases the risk of subsequent development of degenerative changes in the knee. This study deals with the outcome of intraarticular meniscal repair and factors that affect healing. Parameters of interest were type and location of the tear and also the influence of simultaneous reconstruction of a ruptured ACL.

METHODS

We investigated the outcome of 25 patients (29 menisci) aged 15 (4-17) years who underwent surgery for full thickness meniscal tears, either as isolated lesions or in combination with ACL ruptures. Intraoperative documentation followed the IKDC 2000 standard. Outcome measurements were the Tegner score (pre- and postoperatively) and the Lysholm score (postoperatively) after an average follow-up period of 2.3 years, with postoperative arthroscopy and MRT in some cases.

RESULTS

24 of the 29 meniscal lesions healed (defined as giving an asymptomatic patient) regardless of location or type. 4 patients re-ruptured their menisci (all in the pars intermedia) at an average of 15 months after surgery following a new injury. Mean Lysholm score at follow-up was 95, the Tegner score deteriorated, mean preoperative score: 7.8 (4-10); mean postoperative score: 7.2 (4-10). Patients with simultaneous ACL reconstruction had a better outcome.

INTERPRETATION

All meniscal tears in the skeletally immature patient are amenable to repair. All recurrent meniscal tears in our patients were located in the pars intermedia; the poorer blood supply in this region may give a higher risk of re-rupture. Simultaneous ACL reconstruction appears to benefit the results of meniscal repair.

MR imaging of the postoperative knee

Advances in orthopedic and arthroscopic surgical procedures of the knee such as, knee replacement, ligamentous reconstruction as well as articular cartilage and meniscus repair techniques have resulted in a significant increase in the number of patients undergoing knee arthroscopy or open surgery. As a consequence postoperative MR imaging examinations increase. Comprehensive knowledge of the normal postoperative MR imaging appearances and abnormal findings in the knee associated with failure or complications of common orthopedic and arthroscopic surgical procedures currently undertaken is crucial. This article reviews the various normal and pathological postoperative MR imaging findings following anterior and posterior cruciate ligament, medial collateral ligament and posterolateral corner reconstruction, meniscus and articular cartilage surgery as well as total knee arthroplasty with emphasis on those surgical procedures which general radiologists will likely be faced in their daily clinical routine.

Clinical and radiological results 21 years following successful, isolated, open meniscal repair in stable knee joints

The long-term results over 20 years following meniscal repair in stable knees have not been described yet. The objective was therefore to analyze the clinical and radiological outcomes of successful, isolated, open meniscal repairs with an intact ACL after a mean follow-up of 20.6 years (range, 16-25) retrospectively in 26 patients. Clinical evaluation included objective (Lysholm, IKDC, Tegner) and subjective scores. Standard radiological assessment according to Ahlbäck's osteoarthritis classification and weight-bearing full-leg radiography for alignment were performed. Eight patients were excluded due to a re-rupture of the meniscus. In the 18 remaining patients (12 male, 6 female), the mean Lysholm and IKDC score was 97.8 points (range, 85-100) and 93% (range, 77-100) at the most recent follow-up, respectively. The Tegner activity scale averaged 4.2 (range, 3-7). Subjectively, 13 patients rated their outcome excellent, 4 good, and 1 fair. The radiological evaluation demonstrated an average development of "+1" grade (range, 0-"+2") osteoarthritic changes versus preoperatively; however, the contralateral healthy knee also revealed comparable (on average "+1" grade) degenerative changes reflecting natural history. The alignment was not significantly different between the operated and the contralateral leg. Overall, isolated open meniscal repair in stableness has the potential of a successful surgery with good to excellent long-term results. The development of osteoarthritic changes within the femorotibial compartments is mild and comparable to contralateral and the alignment of the axis is preserved. Therefore, repair of a ruptured meniscus is recommended whenever possible, even in isolated meniscal tears. However, a re-rupture rate of approximately 30% in isolated meniscal tears has to be acknowledged, which still reflects the need for biological enhancement of meniscal healing.

Meniscal repair in anterior cruciate ligament reconstruction: a long-term outcome study

PURPOSE

To study the long-term outcome of patients who have undergone inside-out, vertical stacked mattress suture repair of meniscal tears combined with anterior cruciate ligament (ACL) reconstruction.

METHODS

From a database of ACL reconstructed patients, consecutive patients undergoing concomitant meniscal repair and ACL reconstruction between 1991 and 1999 were identified. Patients with previous ACL or meniscal pathology were excluded. Two age- and sex-matched cohorts who had undergone combined ACL reconstruction and menisectomy and who had undergone ACL reconstruction with normal menisci were identified for comparison. Outcome scoring included IKDC and Lysholm scores for the meniscal repair group. Two sample t-tests and chi-square tests were used to compare the IKDC subjective scores, with a minimum level of significance set at 5% (P = 0.05).

RESULTS

Fourty-four patients were identified for analysis with a median follow-up of 10 years (7.7-12.6). Patients undergoing ACL reconstruction combined with meniscal repair had a mean IKDC of 84.2 compared with a mean score of 70.5 (P = 0.008) in patients who had undergone menisectomy and 88.2 (P = 0.005) in patients with intact menisci. 86.2% of patients with ACL reconstruction and meniscal repair had Lysholm score of between 80 and 100%. Sixty-nine percent follow-up was achieved. Survival analysis by life table method shows a best case of 89% 10-years survival.

CONCLUSIONS

This study demonstrates that good long-term outcomes can be obtained in patients up to over 12 years after combined ACL reconstruction and meniscal repair. Improved functional scores can be achieved when compared with ACL reconstruction and menisectomy. The authors advocate repair of meniscal tears during ACL reconstruction unless there is complex tearing, radial tearing or plastic deformation of the remaining meniscus.

LEVEL OF EVIDENCE

III.

Diagnostic values of 3 methods for evaluating meniscal healing status after meniscal repair: comparison among second-look arthroscopy, clinical assessment, and magnetic resonance imaging

BACKGROUND

The main diagnostic methods for evaluating repaired menisci include second-look arthroscopy, clinical assessment, and magnetic resonance imaging (MRI). None of the previous studies applied all 3 methods for each consecutive case nor made any systematic comparison among them.

PURPOSE

This study was undertaken to compare the diagnostic values of the 3 different methods in an attempt to propose suggestions for evaluating meniscal healing results.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

Eighty-one patients (89 menisci), with a mean age of 25.4 years (standard deviation [SD], 7.7; range, 15-50 years), underwent arthroscopic meniscal repair, including 65 medial menisci and 24 lateral menisci. Follow-up evaluation for each meniscus included clinical assessment, second-look arthroscopy, and postoperative MRI, with a mean follow-up time of 25.4 months (SD, 6.0; range, 17.4-48.3 months). Defined criteria for unhealed meniscus were any symptoms such as joint-line tenderness, swelling, locking, or positive McMurray test for clinical assessment; cleft or instability on second-look arthroscopy; and grade 3 signal intensity shown at the repaired site on postoperative MRI.

RESULTS

Seventy-seven menisci were confirmed completely healed by second-look arthroscopy, with a total healing rate of 86.5%. Clinical assessment found 63 menisci healed, with a clinical healing rate of 70.8% (sensitivity, 58.3%; specificity, 75.3%; accuracy, 73.0%). By using the second-look arthroscopy as the standard, the sensitivity, specificity, and accuracy, respectively, were calculated for MRI in 5 sequences: sagittal T1: 91.7%, 58.4%, 62.9%; sagittal proton density (PD): 83.3%, 40.3%, 46.1%; sagittal T2: 58.3%, 89.6%, 85.4%; coronal PD: 75.0%, 74.0%, 74.2%; and coronal T2: 41.7%, 98.7%, 91.0%.

CONCLUSION

Second-look arthroscopy was the most dependable way to determine meniscal healing. Clinical assessment had obvious limitations in diagnosing healed menisci. On MRI examination, T2-weighted sequences had obviously higher specificity and accuracy, while PD and T1 had higher sensitivity. The diagnostic value could be improved by a combined application of different sequences.

Long-term outcome after arthroscopic meniscal repair versus arthroscopic partial meniscectomy for traumatic meniscal tears

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.

Measurements of the quadriceps femoris function after meniscus refixation at the stable athlete's knee

INTRODUCTION

The purpose of this study was to monitor the muscular changes regarding the isokinetic strength and torque pattern of the quadriceps femoris at the stable athlete's knee after meniscus tear refixation.

MATERIALS AND METHODS

Therefore 15 athletes (10 male, 5 female) performing recreational or competitional sports at least five times a week before injury were retrospectively examined in the average 2.5 years after isolated arthroscopic meniscus refixation using Inside Out technique. Next to function and sport activity focused scores the isokinetic peak torque (PT) and in the EMG have been analyzed compared to the uninjured knee.

RESULTS

The mean age was 31.26 years. The time between injury and surgery was in the average 13.7 days. According to our first results the data suggest a complete recovery of functional and muscular pattern after meniscus refixation at the stable athlete's knee. No significant EMG changes for quadriceps femoris were detectable. The PT was fully recovered. The functional and sport activity score analysis (Lysholm and Tegner score) showed no changes in the postoperative long-term follow up compared to the preinjured status.

CONCLUSION

Examining isokinetic PT and the EMG of the quadriceps femoris, these data show no side-to-side differences. Regarding the function and sports activity score system, the functionally high demand patients seem to profit by this procedure.

Magnetic resonance imaging of the postoperative meniscus

Imaging of the postoperative meniscus is a challenge. Nevertheless, magnetic resonance imaging (MRI) of the symptomatic knee after meniscal surgery is a valuable diagnostic study of both the menisci and the entire joint. At present, symptomatic patients who have had partial meniscectomy of less than 25% may be evaluated by MRI. For those with partial meniscectomy of greater than 25% or after meniscal repair, direct or indirect magnetic resonance arthrography (MRA) should be considered. Currently, the decision of whether to perform direct (intra-articular) versus indirect (intravenous) MRA must be reviewed on a case-by-case basis considering both the patient's ability to tolerate intra-articular injection and whether a significant effusion already exists, which will imbue the tear with synovial fluid (making intra-articular injection of less importance). In such cases of significant effusion, indirect MRA would be preferred. If MRI or MRA is contraindicated, computed tomography arthrography seems a promising alternative. For a patient who has undergone meniscal allograft transplantation, MRI seems adequate for detecting meniscocapsular healing, allograft extrusion, and allograft tear. Future improvements in MRI sequencing may obviate the need for invasive modalities.

Retears of postoperative knee meniscus: findings on magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) by using low and high field magnets

PURPOSE

The purpose of this study was to determine the diagnostic performance of magnetic resonance (MR) obtained with intra-articular contrast medium in the evaluation of recurrent meniscal tears using low-field extremity-only and high-field whole-body magnets.

MATERIALS AND METHODS

Postoperative standard MR examinations and MR arthrographies of 95 knees were reviewed. Patients experiencing pain and disability after meniscal repair underwent standard MR and MR arthrography (Gadoterate meglumine 0.0025 mmol/ml) on both a 0.2-T and 1.5-T magnet. In 52 of 95 patients, second-look arthroscopy was performed; in the remaining 43 of 95 patients, clinical follow-up was used as the standard of reference. Sensitivity, specificity, positive and negative predictive values as well as accuracy of MRI/MR arthrographic signs as meniscal morphologic changes and the presence of contrast medium tracking into the tear at T1- and T2-weighted sequences in the detection of recurrent meniscal tears were determined.

RESULTS

All MR and MR arthrograpic signs were sensitive in the detection of recurrent tears (range 80-91%). Abnormal meniscal morphology had low specificity [26% (13/50)] for both the 0.2-T and 1.5-T scanner, whereas accuracy was 55% (52/95) and 57% (54/95), respectively. The presence of contrast medium within the meniscus substance on T2-weighted images had higher value of specificity [84% (42/50)] and accuracy [84% (80/95)] by using low field strength magnet than by using high field strength magnet [74% (37/50) and 81% (77/95), respectively]. Whereas, the increased intrameniscal signal intensity extending to the meniscal surface at T1-weighted sequences after intra-articular contrast medium administration had lower specificity and accuracy on 0.2-T images [84% (42/50) and 82% (78/95), respectively] than on 1.5-T images [90% (45/50) and 88% (84/95), respectively].

CONCLUSION

A diagnosis of recurrent meniscal tear in a previously arthroscopically repaired meniscus can be made both on 0.2-T and 1.5-T magnets on the basis of increased signal on T2-weighted and T1-weighted images in the presence of intra-articular contrast material.

Meniscal repair using an all-inside, rapidly absorbing, tensionable device

PURPOSE

The purpose of this study was to evaluate the clinical success rate of all-inside meniscal repairs using a rapidly absorbing device in patients undergoing concurrent anterior cruciate ligament (ACL) reconstructions.

METHODS

Patients with menisci repaired using the polydioxanone Mitek RapidLoc (Depuy Mitek, Raynham, MA) during concurrent ACL reconstruction were evaluated clinically 2 years following index surgery. We performed examinations on 38 meniscal tears in 30 patients using the International Knee Documentation Committee form and the Knee Disorders Subjective History visual analog scale. We also performed physical examinations for an effusion, joint line tenderness, McMurray's testing, and KT-1000 arthrometry (MEDmetric, San Diego, CA).

RESULTS

The clinical success rate for meniscal repair was 86.8% (33 of 38) at a mean follow-up of 30.4 months (range, 21 to 56 months). Univariate analysis revealed sex as the only predictive variable for failure; all failures occurred in male patients. Nonpredictive variables included tear length, type, and configuration; a duration of more than 3 months, compartment, zone, ligament graft choice, age, follow-up, Tegner score, and visual analog scale score.

CONCLUSIONS

The polydioxanone RapidLoc device was found to have a clinical success rate of 86.8%. These data suggest that the more rapidly absorbing polydioxanone device is effective for all-inside meniscal repair during concurrent ACL reconstruction.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Clinical results of meniscus repair with the meniscus arrow: a 4- to 8-year follow-up study

The short-term clinical results of meniscus repair with the meniscus arrow were promising. Unfavorable outcomes were reported in two studies, with longer follow-up, raising concerns about the efficacy of this device. We retrospectively reviewed 62 patients (mean age 23.7 years; range 14-37 years) that underwent all-inside meniscus repair, using the meniscus arrow. Seventeen patients had an isolated meniscus tear (ACL intact group) and 45 patients concomitant ACL rupture that was reconstructed at the same time with the meniscus repair (ACL reconstructed group). All patients followed a non-aggressive rehabilitation protocol. Follow-up was assessed by clinical examination, Lysholm and Tegner score, IKDC knee examination form and KT-2000 arthrometry for the anteroposterior laxity of the reconstructed knees. At an average follow-up of 73 months (range 49-96 months) there were three failures (4.8%), one from the ACL intact group and two from the ACL reconstructed group. One patient developed arthrofibrosis (ACL reconstructed group) that resolved conservatively. Soft tissue irritation at the repair site was noted in three patients. In two patients the symptoms were transient. In the third patient the arrow tip was cut off under local anaesthesia due to saphenous infrapatellar branch irritation and the symptoms resolved (inappropriate arrow size). KT-2000 arthrometry showed that sagittal knee laxity was less than 3 mm in all reconstructed knees. The mean Tegner activity score decreased from 6.7 (pretrauma) to 6.2 (postoperatively). The average Lysholm score was 96, with normal or nearly normal function of all success knees, according to the IKDC knee examination form. Our results show a high clinical success rate of meniscus repair with the meniscus arrow. We found this device both safe and effective.

Mid-term clinical results of medial meniscus repair with the meniscus arrow in the unstable knee

The medial meniscus is a secondary stabilizer to anterior tibial translation and provides significant stability, especially in an ACL-deficient knee. The purpose of this study is to evaluate the clinical outcome of medial meniscus repair in the unstable knee. Between 1997 and 2002, 11 patients, with a mean age of 25.8 years (range 15-39 years), underwent all-inside medial meniscus repair, using the Meniscus Arrow, for unstable medial meniscus tear in ACL-deficient knees. For various reasons none of these patients underwent ACL reconstruction. The average follow-up was 73 months (range 52-91 months). There were three failures (27.3%) defined as the need for reoperation and partial meniscectomy. The mean Tegner activity score decreased from 6.75 (pretrauma) to 4.5 (postoperatively). The average Lysholm and subjective IKDC scores were 83 and 77.4, respectively. Two patients were graded as B (nearly normal) and six as C (abnormal), according to the IKDC knee evaluation form. KT-2000 arthrometry demonstrated that sagittal knee laxity was more than 5 mm in all knees (side to side difference). MRI demonstrated grade three signal alterations at the repair site of meniscus in three patients and signs of cartilage damage in two patients. All patients were asymptomatic during daily activities but seven out of eight reported pain or effusion after sports. Medial meniscus repair in the ACL-deficient knee is not contraindicated. The need of reducing the level of physical activity is essential.

Arthroscopic meniscal repair: a comparative study between three different surgical techniques

The purpose of this prospective study was to evaluate and compare the results of arthroscopic meniscal repair using three different techniques. Between January 2002 and March 2004, 57 patients who met the inclusion criteria underwent an arthroscopic meniscal repair. The outside-in technique was used in 17 patients (group A), the inside-out in 20 patients (group B), while the rest of the 20 patients (group C) were managed by the all-inside technique using the Mitek RapidLoc soft tissue anchor (Mitek Surgical Products, Westwood, MA, USA). Anterior cruciate ligament (ACL) reconstruction was performed in 29 patients (51%). The criteria for clinical success included absence of joint line tenderness, locking, swelling, and a negative McMurray test. The minimum follow-up was one year for all groups. The mean follow-up was 23 months for group A, 22 months for group B, and 22 months for group C. All meniscal repairs were considered healed according to our criteria in group A, while 19 out of 20 repairs (95%) healed in group B. Finally 7 of 20 repairs (35%) were considered failures in group C and this difference was statistically significant in comparison with other groups. The time required for meniscal repair averaged 38.5 min for group A, 18.1 min for group B, and 13.6 min for group C. Operation time for meniscal repair in group A was statistically longer in comparison with other groups. There were no significant differences among the three groups concerning complications. According to our results, arhtroscopic meniscal repair with the inside-out technique seems to be superior in comparison with the other methods because it offers a high rate of meniscus healing without prolonged operation time.

Midterm and long-term results after arthroscopic suture repair of isolated, longitudinal, vertical meniscal tears in stable knees

BACKGROUND

The long-term outcome of meniscal suture repair has not been firmly established.

PURPOSE

To compare the midterm and long-term functional and radiographic outcome of meniscal suture repairs with the natural history of the uninjured knees of each of a cohort of patients.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Eighty-eight patients with an isolated, longitudinal, vertical tear of one of the menisci within a stable knee were arthroscopically treated with a meniscal suture repair. No patient had a previous surgery, and no additional chondral lesion was present. The opposite knee of each patient was uninjured. Both knees of each patient were examined clinically and radiographically in a retrospective follow-up 5 to 17 years (mean, 10 years) after meniscal repair.

RESULTS

Three patients with postoperative complications and 21 patients whose menisci had to be removed because of rerupture were excluded from further evaluation for purposes of this study. The remaining 64 patients reached a mean Tegner activity level of 6 points (range, 3-10 points) and achieved a mean Lysholm score of 94 points (range, 26-100 points). Osteoarthritis was found in 46 of the injured knees, compared with 27 of the uninjured knees (P = .004). However, 42 of the patients had no difference in the grade of osteoarthritis between the injured knee and the uninjured knee, 19 had a difference of 1 grade, 2 had a difference of 2 grades, and 1 had a difference of 3 grades.

CONCLUSION

Arthroscopic meniscal repair for isolated longitudinal meniscal injuries in stable knees yields favorable functional results, but its effects on the risk of secondary osteoarthritis are not clear.

MRI of menisci repaired with bioabsorbable arrows

OBJECTIVE

To analyze with conventional magnetic resonance imaging (MRI) the signal appearance of menisci repaired with bioabsorbable arrows.

DESIGN AND PATIENTS

Forty-four patients with 47 meniscal tears treated with bioabsorbable arrows underwent follow-up conventional MRI examination. The time interval between the surgery and MRI varied from 5 to 67 months (mean 26 months). Twenty-six patients also had concurrent repair of torn anterior cruciate ligament. The following grades were used to classify meniscal signal intensity: (a) G0; low signal intensity on all sequences and regular configuration in every plane, (b) G1; increased signal intensity within the meniscus, not extending to the meniscal surface, (c) G2; increased signal intensity linear in shape, which may or may not communicate with the capsular margin of the meniscus, without extending to the meniscal surface, and (d) G3; increased signal intensity extending to the meniscal surface.

RESULTS

Thirteen menisci (27.5%) had normal signal intensity, 13 menisci (27.5%) Grade 1 signal intensity, 9 menisci (19%) Grade 2 signal intensity and 12 menisci (26%) Grade 3 signal intensity. The time difference between operation and MRI was statistically significant between the G0 (36 months) and G3 groups (14 months; P = 0.0288). There was no statistical significance in different grades between medial and lateral meniscus or between patients with operated or intact ACL. On physical examination sixteen patients reported slight symptoms, seen evenly in each group.

CONCLUSION

No difference was seen in different grades between patients with operated or intact ACL. The highest incidence of menisci with a Grade 3 signal was seen in patients where surgery was within the last 18 months.

Evaluation of the second-generation meniscus arrow in the fixation of bucket-handle tears in the vascular area of the meniscus. A prospective study of 20 patients with a mean follow-up of 26 months

The purpose of this prospective study was to evaluate whether the shorter degradation time of the second-generation Meniscus Arrow would be adequate to allow meniscal healing and whether equally good results could be achieved compared to the first generation implant. We also wanted to assess whether some of the implant related complications could be avoided with the altered absorption time. A total of 20 patients were included in this study. The mean follow-up was 26 months. The average Lysholm score at the final follow-up was 90. There were 13 second-look arthroscopies performed during the follow-up and in them two failures of the repaired menisci to heal were seen. Seven patients were found with some degree of chondral irritation of the femoral condyle corresponding to the repair site. The second generation Meniscus Arrow seems to give results comparable to the first generation Meniscus Arrow. The potential complications caused by the implant reported in the earlier literature using the first generation arrow are possible also using this implant. In seven of the 13 second-look arthroscopies some degree of chondral irritation corresponding to the repair site was seen. The clinical relevance of these lesions remains to be seen.

[MRI after meniscus and cruciate ligament surgery]

Nowadays, due to its high diagnostic accuracy, MR imaging is the method of choice for the evaluation of knee joint disorders pre- and postoperatively. Accurate diagnosis is sometimes possible only if the reporting radiologist has knowledge of the therapeutic procedures and the surgical report. Frequently, further therapeutic management is strongly influenced by MR examinations and radiological reports.

MR imaging evaluation of the postoperative knee: ligaments, menisci, and articular cartilage

The surgical management of knee injuries has increased in recent years. Postoperative magnetic resonance (MR) imaging of the knee following surgical intervention serves an important role in the diagnostic evaluation of patients with recurrent or residual symptoms following surgical intervention. MR imaging additionally assists in the noninvasive documentation of temporal changes at the surgical site potentially reflective of procedural success, or failure. Background understanding of the common surgical procedures performed, their normal postoperative MR imaging appearance, and imaging features of potential procedural complications are essential in the accurate evaluation of patients following prior knee surgery. The focus of the following article is to review the clinical and MR imaging features of the postoperative knee following prior surgical treatment of ligamentous, meniscal, and articular cartilage injuries of the joint.

Arthroscopic meniscal repair with an absorbable screw: results and surgical technique

The results of a new method for arthroscopic all-inside meniscus repair using a biodegradable cannulated screw (Clearfix meniscal screw) were assessed in a medium-term follow-up prospective study. The Clearfix meniscal screw system consists of delivery cannulae, screw driver, and screw implants. After tear debridement, a screw is located on the driver and passed through the cannula to the insertion site, holding the two sides of the tear together under linear compression. Forty-eight patients (48 repairs) with a mean age of 32.7 years were included in the study. Ligament stabilizing procedures were done in 39 patients (81%) who had anterior cruciate ligament deficient knees. Only longitudinal lesions in the red/red or red/white zone were repaired. Follow-up averaged 19 months, with a range from 12 to 48 months. Patients were evaluated using clinical examination, the "Orthopaedische Arbeitsgemeinschaft Knie (OAK)" knee evaluation scheme and magnetic resonance imaging (MRI). Criteria for clinical success included absence of joint-line tenderness, absence of swelling and a negative McMurray test. Postoperatively, there were no complications directly associated with the device. Twelve of 48 repaired menisci (25%) were considered failures according to the above-mentioned criteria. According to the OAK knee evaluation scheme, 38 patients (79%) had an excellent or good result. MRI, however, showed persisting grade III or IV lesions in 35 patients (73%). Analysis showed that age, length of tear, and simultaneous anterior cruciate ligament reconstruction did not affect the clinical outcome. In contrast, risk factors for failure of meniscus repair are chronicity of injury, location of tear more than 3 mm from the meniscosynovial junction and meniscus side (medial).

Imaging the post-operative meniscus

Considerable developments have occurred in meniscal surgery, and consequently in the imaging of post-operative menisci, over the last 15 years. A drive to preserve meniscal physiologic function for as long as possible, in order to delay osteoarthrosis, has resulted in limited partial meniscectomies, meniscal repairs and meniscal transplants. Each of these techniques affects the imaging appearance of the meniscus, reducing the accuracy of conventional MRI in predicting recurrent tears. The specificity of conventional MRI can be improved by employing at least two T2-weighted sequences, but this still leaves a shortfall in sensitivity. In an attempt to increase the diagnostic accuracy of cross-sectional imaging, MR arthrography (MRA) and CT arthrography (CTA), have been applied to the post-operative meniscus. Sensitivities and specificities for these two techniques approach 90% in predicting recurrent meniscal tears. In the setting of clinical symptoms and gross meniscal deficiency, meniscal allografts are being transplanted with increasing frequency. In these transplants meniscal degeneration, fragmentation and separation are common findings, but the role of imaging in the management of these patients has not yet been well defined. This review explores the imaging techniques available for the evaluation of the post-operative meniscus, their strengths and weaknesses, and the reasons that they may find a place in a rational strategy for imaging of the symptomatic post-operative knee.