Long-term outcome of meniscectomy: symptoms, function, and performance tests in patients with or without radiographic osteoarthritis compared to matched controls

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.

Gender Effect on the Outcome of Partial Medial Meniscectomy

Complex posterior horn tears of the medial meniscus are common. Previous reports performed statistical stratifications to address the influence of gender on outcome following arthroscopic partial medial meniscectomy with variable conclusions. The aim of this study was to compare the clinical results of arthroscopic partial meniscectomy of the knee between men and women with complex medial meniscal tear type while controlling for other variables that may affect outcome. This study compared groups of 86 men and 49 women who were followed prospectively using the Lysholm Knee Scoring Scale, the visual analogue scale, and patient's satisfaction. Mean age at operation was 51 years and mean follow-up was 26 months. Mean Lysholm score improved from 69 preoperatively to 82.1 postoperatively (P<.001) in the male group and from 64.2 preoperatively to 73.5 postoperatively (P=.04) in the female group. At last follow-up, 68 (79%) men and 35 (71%) women stated that they were satisfied with the operation. In both groups, the severity of chondral lesions was found to be negatively correlated to the preoperative score. Women had more severe chondral lesions at arthroscopy than men. This comparative study showed no significant difference between men and women in terms of clinical improvement following arthroscopic partial meniscectomies of complex tear types in stable knees with intact lateral meniscus. Women had lower functionality pre- and postoperatively, which correlated with more severe chondral degeneration at surgery compared with men.

Meniscal allograft transplantation: how should we be doing it? A systematic review

PURPOSE

We undertook a systematic review to assess a number of the technical aspects of meniscal allograft transplantation (MAT) that have not been covered in other reviews. Specific variables studied included the indications for MAT, graft fixation method, rehabilitation protocols, outcome scores, and definition of failure.

METHODS

We performed a systematic literature review of the PubMed, EMBASE, and Cochrane databases to determine the outcomes of meniscal transplantation at greater than 2 years postoperatively. PRISMA (Preferred Reporting for Systematic Reviews and Meta-Analyses) guidelines were followed with a PRISMA checklist. The search was completed on January 5, 2014.

RESULTS

These queries returned 629 results from which 41 articles were identified as meeting the inclusion criteria. No studies in this review were randomized or controlled.

CONCLUSIONS

MAT is a worthwhile procedure, with evidence that it provides pain relief and improved function, and good results reported in mid- to long-term studies. The procedure should be considered only in a patient with localized pain and a stable (or stabilized) and well-aligned (or realigned) knee. The controversial areas studied in this review include the following: there is no evidence to support fixation with either bone plugs or soft tissue; there is no standardized rehabilitation program, but it appears that full weight bearing by 6 weeks is not detrimental; and a clear and uniform definition of failure and use of consistent outcome scores would aid future reporting and analysis of the results of meniscal transplantation.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II to IV studies.

Mechanobiology of the meniscus

The meniscus plays a critical biomechanical role in the knee, providing load support, joint stability, and congruity. Importantly, growing evidence indicates that the mechanobiologic response of meniscal cells plays a critical role in the physiologic, pathologic, and repair responses of the meniscus. Here we review experimental and theoretical studies that have begun to directly measure the biomechanical effects of joint loading on the meniscus under physiologic and pathologic conditions, showing that the menisci are exposed to high contact stresses, resulting in a complex and nonuniform stress-strain environment within the tissue. By combining microscale measurements of the mechanical properties of meniscal cells and their pericellular and extracellular matrix regions, theoretical and experimental models indicate that the cells in the meniscus are exposed to a complex and inhomogeneous environment of stress, strain, fluid pressure, fluid flow, and a variety of physicochemical factors. Studies across a range of culture systems from isolated cells to tissues have revealed that the biological response of meniscal cells is directly influenced by physical factors, such as tension, compression, and hydrostatic pressure. In addition, these studies have provided new insights into the mechanotransduction mechanisms by which physical signals are converted into metabolic or pro/anti-inflammatory responses. Taken together, these in vivo and in vitro studies show that mechanical factors play an important role in the health, degeneration, and regeneration of the meniscus. A more thorough understanding of the mechanobiologic responses of the meniscus will hopefully lead to therapeutic approaches to prevent degeneration and enhance repair of the meniscus.

Tibiofemoral loss of contact area but no changes in peak pressures after meniscectomy in a Lapine in vivo quadriceps force transfer model

PURPOSE

The menisci are thought to modulate load transfer and to absorb shocks in the knee joint. No study has experimentally measured the meniscal functions in the intact, in vivo joint loaded by physiologically relevant muscular contractions.

METHODS

Right knee joints of seven New Zealand white rabbits were loaded using isometric contractions of the quadriceps femoris muscles controlled by femoral nerve stimulation. Isometric knee extensor torques at the maximal and two submaximal force levels were performed at knee angles of 70°, 90°, 110°, and 130°. Patellofemoral and tibiofemoral contact areas and pressure distributions were measured using Fuji Presensor film inserted above and below the menisci and also with the menisci removed.

RESULTS

Meniscectomy was associated with a decrease in tibiofemoral contact area ranging from 30 to 70% and a corresponding increase in average contact pressures. Contact areas measured below the menisci were consistently larger than those measured on top of the menisci. Contact areas in the patellofemoral joint (PFJ), and peak pressures in tibiofemoral and PFJs, were not affected by meniscectomy. Contact areas and peak pressures in all joints depended crucially on knee joint angle and quadriceps force: The more flexed the knee joint was, the larger were the contact areas and the higher were the peak pressures.

CONCLUSIONS

In agreement with the literature, removal of the menisci was associated with significant decreases in tibiofemoral contact area and corresponding increases in average contact pressures, but surprisingly, peak pressures remained unaffected, indicating that the function of the menisci is to distribute loads across a greater contact area.

Correlation between body mass index and chondral lesions in isolated medial meniscus tears

BACKGROUND

Chondral lesions of the knee are commonly found during arthroscopic partial meniscectomy. The literature advises against arthroscopic medial meniscectomy in the presence of advanced chondral derangement because of unfavorable outcome. Recent studies have shown an association between obesity and chondropathy in patients with meniscal tears. The aim of this study was to assess whether body mass index (BMI) correlates with the severity of chondral lesions in patients with isolated medial meniscus tears (i.e. without ligamentous or lateral meniscal injury).

MATERIALS AND METHODS

837 knee arthroscopies were performed in a regional referral center of arthroscopic surgery between January 2011 and December 2012. Of these 168 (109 males, 59 females) patients with no axial knee deformity and no radiological signs of osteoarthritis who have had arthroscopic debridement for isolated torn medial meniscus were included in the study. The correlation between different demographic factors and the level of chondral damage reported at surgery was evaluated. The mean age of patient was 50 years (range 13-82 years) and an average BMI was 28.2 kg/m(2) (range17.5-42.5 kg/m(2)).

RESULTS

Overall, regression analysis showed both age and BMI to be linearly correlated to chondral score (r = 0.53, P < 0.04); however, there were no advanced chondral lesions found in patients younger than 40 years of age and all severe lesions were at age 50 years or more. Therefore, further analysis was performed for age subgroups: patients were grouped as younger than 40, between the age of 40 and 50 (middle age) and older than 50 years. The BMI was linearly correlated to the severity of chondral score exclusively in the middle aged group (i.e. 40-50 years old). There was no correlation between activity level and chondral damage. Women had worse chondral lesions than men in all age groups.

CONCLUSION

Higher BMI in middle aged patients with isolated medial meniscus tears and unremarkable radiographs may predict more advanced chondral lesions at arthroscopy.

Cartilage degeneration and not age influences the health-related quality of life outcome after partial meniscectomy

PURPOSE

The purpose of this study is to investigate whether inconsistently reported factors influence the health-related quality of life (HRQOL) outcome of partial meniscectomy.

METHOD

Short Form 36 (SF-36) data on 216 patients were retrospectively analysed for the influence of the factors age, gender and degree of cartilage degeneration. Mixed linear models were applied for univariate and multivariate analyses.

RESULTS

All SF-36 scales, including the psychosocial scales, showed a significant improvement from pre- to post-operative (p < 0.001). The factor 'degree of cartilage degeneration' was found to significantly influence post-surgical improvement of the SF-36 'physical component summary' score. Patients with mild cartilage degeneration benefited significantly more from surgery than did patients with advanced cartilage degeneration (p = 0.011). Older patients had significantly lower scores on each subscale, but showed no significant age-time interaction, that is, no association was seen between age and the degree of improvement. No effect was determined for the variable gender.

CONCLUSIONS

The findings of the current study can be interpreted to show that arthroscopic partial meniscectomy significantly improves HRQOL, even in mental or psychosocial dimensions of HRQOL. Not age but the degree of cartilage degeneration influences the HRQOL gain that can be expected. The factor gender has no effect on HRQOL. The findings of our study influence our daily routine, in that we take the degree of cartilage degeneration and not age as predictive value for the success to be anticipated from the procedure. Concerning the preoperative consenting, it is important to mention that advanced cartilage degeneration is a predictor of a less favourable outcome.

LEVEL OF EVIDENCE

IV.

Why menisci show higher healing rate when repaired during ACL reconstruction? Growth factors release can be the explanation

PURPOSE

Healing rate of meniscus repair is higher when the suture is associated with anterior cruciate ligament reconstruction. A possible explanation can be a different pattern of release of growth factors between anterior cruciate ligament reconstruction and isolated meniscus surgery. Hypothesis of this study is that the concentrations of bFGF, TGF-β and platelet-derived growth factor (PDGF) in joint fluid, immediately after single-bundle anterior cruciate ligament reconstruction and arthroscopic partial meniscectomy, can be different.

METHODS

Twenty consecutive patients underwent partial medial meniscectomy and twenty consecutive patients underwent single-bundle anterior cruciate ligament reconstruction with hamstring grafts were enrolled in the study. Thirty minutes after the end of the surgical procedure, a sample of joint fluid, as well of venous blood, was collected from all the patients. Concentrations of growth factors were determined by enzyme-linked immunosorbent assay.

RESULTS

The peripheral blood concentration of TGF-β, bFGF and PDGF was comparable between partial meniscectomy and anterior cruciate ligament reconstruction groups. No differences between the two surgical techniques were also found in term of TGF-β and bFGF joint fluid concentration, whereas joint PDGF concentration of anterior cruciate ligament reconstruction patients was significantly higher than the one found in partial meniscectomy patients.

CONCLUSIONS

A significant growth factors release was detected in the knee joint during arthroscopic surgery. PDGF concentration was significantly higher in anterior cruciate ligament reconstructed knee than in the meniscectomy group. PDGF can play an important role enhancing the healing response of meniscus suture and can be one of the biological reasons of the higher meniscal healing rate in anterior cruciate ligament reconstructed knee.

Medial meniscus tear morphology and related clinical symptoms in patients with medial knee osteoarthritis

PURPOSE

The objective of this study was to examine the association between clinical symptoms and arthroscopic meniscal findings in patients with early to moderate medial knee osteoarthritis.

METHODS

One hundred and four patients (110 knees) were selected from a group of 132 patients (140 knees) aged ≥50 years who underwent arthroscopic surgery for medial meniscal tears. Inclusion criteria were as follows: (a) medial knee osteoarthritis and (b) simple medial meniscal tears extending to ≥1/4 of the meniscal margin. Subjective symptoms, location and nature of the pain, as well as the physical findings observed during initial assessment were evaluated using a standardized assessment chart. The relationship between arthroscopic meniscal findings and clinical symptoms was then analysed.

RESULTS

Isolated meniscal tears were classified into four types: radial tear of the middle segment; posterior root tear; horizontal tear of the posterior segment; and flap tear. The following symptoms were reported at significantly higher frequencies: pain on standing and a catching sensation in patients with flap tears; pain on walking and nocturnal pain on rolling over in bed in patients with radial tears of the middle segment; and popliteal pain in patients with posterior root tears.

CONCLUSIONS

This study demonstrates a relationship between the type of medial meniscal tear and characteristic clinical symptoms reported by patients with medial knee osteoarthritis. These results suggest that clinical symptoms in patients with osteoarthritis of the knee may be caused by meniscal tears. This evidence may help to better inform patients and surgeons regarding choice of treatment.

LEVEL OF EVIDENCE

Case control study, Level III.

Long-term follow-up of nonoperatively and operatively treated acute primary patellar dislocation in skeletally immature patients

Purpose. The present study reports a long-term follow-up of acute primary patellar dislocation in patients with open physes. The purpose of the study was to evaluate knee function and recurrence rates after surgical and nonsurgical treatment of patellar dislocation. Methods. A total of 51 patients, including 29 girls and 22 boys, who were 9–14 years of age at the time of injury, were retrospectively evaluated. The minimum follow-up time was 5 years. Thigh muscle torque, range of motion, the squat test, the knee injury and osteoarthritis outcome score (KOOS), the Kujala score, and the recurrence rate were registered. Radiological predisposing factors at the time of injury were determined. Results. Quality of life and sports/recreation were the most affected subscales, according to KOOS, and a reduced Kujala score was also observed in all treatment groups. The surgically treated patients had a significantly lower recurrence rate. Those patients also exhibited reduced muscle performance, with a hamstring to quadriceps ratio (H/Q) of 1.03. The recurrence rate was not correlated with knee function. Conclusions. Patellar dislocation in children influences subjective knee function in the long term. Surgery appears to reduce the recurrence rate, but subjective knee function was not restored.

The effect on knee-joint load of instruction in analgesic use compared with neuromuscular exercise in patients with knee osteoarthritis: study protocol for a randomized, single-blind, controlled trial (the EXERPHARMA trial)

BACKGROUND

Knee osteoarthritis (OA) is a mechanically driven disease, and it is suggested that medial tibiofemoral knee-joint load increases with pharmacologic pain relief, indicating that pharmacologic pain relief may be positively associated with disease progression. Treatment modalities that can both relieve pain and reduce knee-joint load would be preferable. The knee-joint load is influenced by functional alignment of the trunk, pelvis, and lower-limb segments with respect to the knee, as well as the ground-reaction force generated during movement. Neuromuscular exercise can influence knee load and decrease knee pain. It includes exercises to improve balance, muscle activation, functional alignment, and functional knee stability. The primary objective of this randomized controlled trial (RCT) is to investigate the efficacy of a NEuroMuscular EXercise (NEMEX) therapy program, compared with optimized analgesics and antiinflammatory drug use, on the measures of knee-joint load in people with mild to moderate medial tibiofemoral knee osteoarthritis.

METHOD/DESIGN

One hundred men and women with mild to moderate medial knee osteoarthritis will be recruited from general medical practices and randomly allocated (1:1) to one of two 8-week treatments, either (a) NEMEX therapy twice a week or (b) information on the recommended use of analgesics and antiinflammatory drugs (acetaminophen and oral NSAIDs) via a pamphlet and video materials. The primary outcome is change in knee load during walking (the Knee Index, a composite score of the first external peak total reaction moment on the knee joint from all three planes based on 3D movement analysis) after 8 weeks of intervention. Secondary outcomes include changes in the external peak knee-adduction moment and impulse and functional performance measures, in addition to changes in self-reported pain, function, health status, and quality of life.

DISCUSSION

These findings will help determine whether 8 weeks of neuromuscular exercise is superior to optimized use of analgesics and antiinflammatory drugs regarding knee-joint load, pain and physical function in people with mild to moderate knee osteoarthritis.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01638962 (July 3, 2012).

Repair of horizontal meniscus tears: a systematic review

PURPOSE

Despite the well-documented advantages of meniscal repair over meniscectomy, horizontal cleavage tears (HCTs) are often not repaired. Reported reasons include difficulty performing the repair, potential suture failure due to mechanical stresses, and poor healing rates. In addition, many surgeons have the perception that debriding the tear until the superior and inferior laminae are stable results in a good clinical outcome. Furthermore, many of the tears occur in patients who are older than the generally accepted indicated age for repair and may also have a degenerative component, making them potentially less likely to benefit from repair. This review was performed to evaluate the published outcomes of HCT repairs and test the hypothesis that surgically repaired HCTs have an unacceptably low rate of success.

METHODS

A systematic search of the PubMed and Embase databases was performed in December 2013 to identify studies in which meniscal HCTs were repaired. Inclusion criteria for the analysis were English language, reference to a patient with an HCT repaired by any method, and a report of at least 1 postoperative outcome. For the purposes of this review, a failed outcome was defined as the need for reoperation.

RESULTS

More than 16,000 abstracts were returned in the search. From these abstracts, we identified 210 articles for further review, of which 9 met the inclusion criteria. A total of 98 repairs of horizontal tears were evaluated in these studies. By use of reoperation as the criterion for treatment failure, 77 of the repairs were successful, for an overall success rate of 77.8%.

CONCLUSIONS

The literature does not support the hypothesis that surgically repaired HCTs have an unacceptably low rate of success. Rather, our results show that existing studies of repaired HCTs show a comparable success rate to repairs of other types of meniscal tears.

LEVEL OF EVIDENCE

Level IV, systematic review of Level IV studies.

Anterior cruciate ligament injury and radiologic progression of knee osteoarthritis: a systematic review and meta-analysis

BACKGROUND

Knee osteoarthritis after anterior cruciate ligament (ACL) injury has previously been reported. However, there has been no meta-analysis reporting the development and progression of osteoarthritis.

PURPOSE

We present the first meta-analysis reporting on the development and progression of osteoarthritis after ACL injury at a minimum mean follow-up of 10 years, using a single and widely accepted radiologic classification, the Kellgren & Lawrence classification.

STUDY DESIGN

Meta-analysis.

METHOD

Articles were included for systematic review if they reported radiologic findings of ACL-injured knees and controls using the Kellgren & Lawrence classification at a minimum mean follow-up period of 10 years. Appropriate studies were then included for meta-analysis.

RESULTS

Nine studies were included for systematic review, of which 6 studies were further included for meta-analysis. One hundred twenty-one of 596 (20.3%) ACL-injured knees had moderate or severe radiologic changes (Kellgren & Lawrence grade III or IV) compared with 23 of 465 (4.9%) uninjured ACL-intact contralateral knees. After ACL injury, irrespective of whether the patients were treated operatively or nonoperatively, the relative risk (RR) of developing even minimal osteoarthritis was 3.89 (P < .00001), while the RR of developing moderate to severe osteoarthritis (grade III and IV) was 3.84 (P < .0004). Nonoperatively treated ACL-injured knees had significantly higher RR (RR, 4.98; P < .00001) of developing any grade of osteoarthritis compared with those treated with reconstructive surgery (RR, 3.62; P < .00001). Investigation of progression to moderate or severe osteoarthritis (grade III or IV only) after 10 years showed that ACL-reconstructed knees had a significantly higher RR (RR, 4.71; P < .00001) compared with nonoperative management (RR, 2.41; P = .54). It was not possible to stratify for return to sports among the patients undergoing ACL reconstruction.

CONCLUSION

Results support the proposition that ACL injury predisposes knees to osteoarthritis, while ACL reconstruction surgery has a role in reducing the risk of developing degenerative changes at 10 years. However, returning to sports activities after ligament reconstruction may exacerbate the development of arthritis.

The human meniscus: a review of anatomy, function, injury, and advances in treatment

Meniscal injuries are recognized as a cause of significant musculoskeletal morbidity. The menisci are vital for the normal function and long-term health of the knee joint. The purpose of this review is to provide current knowledge regarding the anatomy and biomechanical functions of the menisci, incidence, injury patterns and the advancements in treatment options of meniscal injury. A literature search was performed by a review of PubMed, Google Scholar, MEDLINE, and OVID for all relevant articles published between 1897 and 2014. This study highlights the anatomical and biomechanical characteristics of the menisci, which may be relevant to injury patterns and treatment options. An understanding of the normal anatomy and biomechanical functions of the knee menisci is a necessary prerequisite to understanding pathologies associated with the knee.

Vertical Tears of the Lateral Meniscus: Effects on In Vitro Tibiofemoral Joint Mechanics

BACKGROUND

Lateral meniscal tears are often seen with acute anterior cruciate ligament (ACL) injury and may be left in situ, repaired, or treated with meniscectomy. Clinical studies have shown good outcomes with vertical tears left in situ and poor outcomes following meniscectomy. However, clinically relevant studies are needed to establish a biomechanical foundation for treatment of these tears, particularly regarding the effects of meniscectomy.

PURPOSE

To compare tibiofemoral joint mechanics following vertical lateral meniscal tears and meniscectomies. We hypothesized that a peripheral vertical tear of the lateral meniscus would alter joint mechanics, increasing contact pressure and area, and that more drastic effects would be seen following meniscectomy, at higher knee flexion angles, and with increased loads.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten fresh-frozen cadaveric knees (average age, 55 ± 12 years) were tested with 5 lateral meniscus states: intact, short vertical tear, extended vertical tear, posterior horn partial meniscectomy (rim intact), and posterior horn subtotal meniscectomy (rim excised). The specimens were loaded axially at knee flexion angles of 0°, 30°, and 60°, and musculotendinous forces were applied, simulating a 2-legged squat. Intra-articular contact pressures were measured using pressure-sensitive Fuji film. Kinematic data were acquired through digitization of fiducial markers.

RESULTS

Vertical tears did not cause a significant change in contact pressure or area. Partial meniscectomy increased maximum contact pressures in the lateral compartment at 30° and 60° from 5.3 MPa to 7.2 MPa and 7.6 MPa, respectively (P = .02, P = .007). Subtotal meniscectomy (8.4 MPa) significantly increased contact pressure compared with partial meniscectomy (7.6 MPa) at 60° (P = .04). Both meniscectomy states significantly increased contact pressures with increasing flexion from 0° to 60° (P < .001, P < .001).

CONCLUSION

Vertical tears of the lateral meniscus during a simulated 2-legged squat did not significantly change contact pressures and areas compared with an intact meniscus. However, treating these tears with partial and complete meniscectomy significantly increased maximum contact pressures.

CLINICAL RELEVANCE

Biomechanical evidence supports treating vertical lateral meniscus tears with meniscal-sparing techniques as opposed to meniscectomy, which may lead to progressive degenerative joint disease from altered joint biomechanics.

The relationship between lateral meniscus shape and joint contact parameters in the knee: a study using data from the Osteoarthritis Initiative

Introduction

The meniscus has an important role in force transmission across the knee, but a detailed three-dimensional (3D) morphometric shape analysis of the lateral meniscus to elucidate subject-specific function has not been conducted. The aim of this study was to perform 3D morphometric analyses of the lateral meniscus in order to correlate shape variables with anthropometric parameters, thereby gaining a better understanding of the relationship between lateral meniscus shape and its load-bearing function.

Methods

The lateral meniscus (LM) was manually segmented from magnetic resonance images randomly selected from the Osteoarthritis Initiative (OAI) non-exposed control subcohort. A 3D statistical shape model (SSM) was constructed to extract the principal morphological variations (PMV) of the lateral meniscus for 50 subjects (25 male and 25 female). Correlations between the principal morphological variations and anthropometric parameters were tested. Anthropometric parameters that were selected included height, weight, body mass index (BMI), femoral condyle width and axial rotation.

Results

The first principal morphological variation (PMV) was found to correlate with height (r = 0.569), weight (r = 0.647), BMI (r = 0.376), and femoral condyle width (r = 0.622). The third PMV was found to correlate with height (r = 0.406), weight (r = 0.312), and femoral condyle width (r = 0.331). The percentage of the tibial plateau covered by the lateral meniscus decreases as anthropometric parameters relating to size of the subject increase. Furthermore, when the size of the subject increases, the posterior and anterior horns become proportionally longer and wider.

Conclusion

The correlations discovered suggest that variations in meniscal shape can be at least partially explained by the levels of loads transmitted across the knee on a regular basis. Additionally, as the size of the subject increases and body weight rises, the coverage percentage of the meniscus is reduced, suggesting that there would be an increase in the load-bearing by the cartilage. However, this reduced coverage percentage is compensated by the proportionally wider and longer meniscal horn.

Is postoperative exercise therapy necessary in patients with degenerative meniscus? A randomized controlled trial with one year follow-up

PURPOSE

There is no consensus on a postoperative rehabilitation regimen for patients who have undergone surgery for medial meniscus damage. The aim of this investigation was to evaluate two rehabilitation approaches after arthroscopic surgery in patients with degenerative meniscus: supervised medical exercise therapy versus no treatment.

METHODS

A prospective randomized controlled clinical trial. Over 4 months, 70 participants were randomly assigned into either a medical exercise therapy group (n = 36) or a control group (n = 34). Pain was a composite score of a visual analogue scale (VAS), and function was measured with a functional assessment questionnaire (KOOS), while anxiety and depression were measured with the Hospital Anxiety and Depression Scale. Function was also measured with tests of quadriceps femoris strength and a one-leg jump test.

RESULTS

Prognostic variables were similar between the groups at baseline, with five (7 %) patients dropping out during the treatment period and another six (8 %) before the one-year follow-up. After 3 months, the medical exercise therapy group achieved significantly better outcome effects than the control group for pain and function. The results after the 12-month follow-up indicated the same results as at posttest, whereas Hospital Anxiety and Depression Scale, fiveRM and the one-leg hop test also demonstrated a significant difference between the groups from pre- to posttest to follow-up.

CONCLUSION

In patients with surgery for degenerative meniscus damage, postoperative medical exercise therapy is an efficient treatment alternative compared to no treatment.

Clinical healing rates of meniscus repairs of tears in the central-third (red-white) zone

PURPOSE

To determine the clinical healing rate of repairs of meniscus tears that extend into the central one-third region and the factors that affect the outcome.

METHODS

A systematic search of PubMed was conducted to determine the outcome of meniscus repairs in the red-white (R/W) zone. Inclusion criteria were as follows: English language, clinical trials published from 1996 to 2013, R/W tears analyzed separately from tears in other zones, arthroscopic suture-based repairs, and all evidence levels.

RESULTS

Of 344 articles identified, 23 met the inclusion criteria. There were 1,232 patients who had 1,326 meniscus repairs, of which 767 were in the R/W zone. Concurrent anterior cruciate ligament reconstruction was performed in 955 patients (78%). The mean age was 25 years, and the mean follow-up was 4 years. Evaluation criteria included clinical examination in 22 studies, follow-up arthroscopy in 15, magnetic resonance imaging in 6, weight-bearing radiographs in 3, and the International Knee Documentation Committee subjective score in 1. Overall, 637 (83%) of the repairs were considered clinically healed because no additional surgery was required and no obvious clinical meniscus symptoms were detected. This included 382 of 470 inside-out suture repairs (81%) and 255 of 297 all-inside suture repairs (86%). Twenty-two factors were assessed in 13 studies to determine their influence on the outcome, with varying results. Authors generally found that patient age, chronicity of injury, involved tibiofemoral compartment, gender, and concurrent anterior cruciate ligament reconstruction did not adversely affect the results. Insufficient data existed to assess the healing rates according to the type of meniscus tear except for single longitudinal tears. Complications were reported in 3% of the patients in this review. Long-term assessment of a chondroprotective effect of the repairs was conducted in only 2 studies.

CONCLUSIONS

An acceptable midterm clinical healing rate was found for R/W meniscus repairs, supporting this procedure when appropriately indicated. Long-term studies assessing the chondroprotective effect in the involved tibiofemoral compartment using magnetic resonance imaging and radiographs are needed.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I-IV studies.

Arthroscopic partial meniscectomy versus sham surgery for a degenerative meniscal tear

BACKGROUND

Arthroscopic partial meniscectomy is one of the most common orthopedic procedures, yet rigorous evidence of its efficacy is lacking.

METHODS

We conducted a multicenter, randomized, double-blind, sham-controlled trial in 146 patients 35 to 65 years of age who had knee symptoms consistent with a degenerative medial meniscus tear and no knee osteoarthritis. Patients were randomly assigned to arthroscopic partial meniscectomy or sham surgery. The primary outcomes were changes in the Lysholm and Western Ontario Meniscal Evaluation Tool (WOMET) scores (each ranging from 0 to 100, with lower scores indicating more severe symptoms) and in knee pain after exercise (rated on a scale from 0 to 10, with 0 denoting no pain) at 12 months after the procedure.

RESULTS

In the intention-to-treat analysis, there were no significant between-group differences in the change from baseline to 12 months in any primary outcome. The mean changes (improvements) in the primary outcome measures were as follows: Lysholm score, 21.7 points in the partial-meniscectomy group as compared with 23.3 points in the sham-surgery group (between-group difference, -1.6 points; 95% confidence interval [CI], -7.2 to 4.0); WOMET score, 24.6 and 27.1 points, respectively (between-group difference, -2.5 points; 95% CI, -9.2 to 4.1); and score for knee pain after exercise, 3.1 and 3.3 points, respectively (between-group difference, -0.1; 95% CI, -0.9 to 0.7). There were no significant differences between groups in the number of patients who required subsequent knee surgery (two in the partial-meniscectomy group and five in the sham-surgery group) or serious adverse events (one and zero, respectively).

CONCLUSIONS

In this trial involving patients without knee osteoarthritis but with symptoms of a degenerative medial meniscus tear, the outcomes after arthroscopic partial meniscectomy were no better than those after a sham surgical procedure. (Funded by the Sigrid Juselius Foundation and others; ClinicalTrials.gov number, NCT00549172.).

Return to sport after arthroscopic meniscectomy on stable knees

Background

Athletes suffering from any injuries want to know when they will be able to return sports activity. The period of return-to-sport after the arthroscopic meniscectomy is still unknown. The aim of this study is to investigate the period of the return-to-sport from surgery and the clinical symptoms after the meniscectomy on stable knees.

Methods

Fifty-six athletes who underwent the arthroscopic meniscectomy were evaluated. The patients with an average age of 26.7 years (range, 13–67) comprised 45 men and 11 women, 16 medial meniscus and 40 lateral meniscus injuries. The average of the follow-up period was 9.2 months. The parameter examined were age, the injured side of meniscus (medial or lateral), articular cartilage status, amount of resection, and sports activity level.

Results

The mean period was 54 days in young group, and was 89 days in old group (p = 0.0013). The period was 79 days in medial meniscus (MM) injured group, and was 61 days in lateral meniscus (LM) group (p = 0.017). There was a significant difference among the groups in activity levels and in amount of resection. Pain and/or effusion in the knee after the return-to-sport were found 22% of the MM group and 53% in the LM group.

Conclusions

The period of the return-to-sport was shorter in young age, high activity and large amount of resection group. Although athletes in LM group can return to sports earlier than those in MM group, more than half of athletes have pain or effusion at the time of return-to sport.

Complex cartilage cases in the athletic patient: advances in malalignment, instability, articular defects, and meniscal insufficiency

For sports medicine specialists, patients presenting with multiple coexisting knee pathologies can be some of the most difficult to treat patients, especially those with cartilage pathology. In particular, articular cartilage lesions are often incidental findings, and the decision to treat patients must be based on the lesions' confirmed contribution to patient symptomatology. The combination of malalignment, ligamentous instability, and chondral/meniscal damage in patients is challenging to treat because of the difficulty in determining both the relative contribution of each of the pathologies to patient clinical condition and the timing of performing specific corrective procedures. Corrective operations performed in isolation to treat each of the pathologies have historically produced reasonable results in patients; however, combined procedures for treatment of combined pathologies may prove essential for the success of any single procedure. This review describes the clinical evaluation of patients with multiple coexisting knee pathologies and highlights current evidence-based treatment strategies for the management of these combined disorders.

Cross-sectional analysis of trends in meniscectomy and meniscus repair

Knee arthroscopy to address meniscus tears is among the most common orthopedic procedures performed, and technical advances in the treatment of meniscus tears have affected the treatment options available to orthopedic surgeons. The purpose of this study was to perform a large cross-sectional analysis of orthopedic patients to investigate trends in arthroscopic meniscectomy and meniscus repair in the United States. Patients who underwent arthroscopic meniscectomy (Current Procedural Terminology codes 29881 and 29880) and arthroscopic meniscus repair (Current Procedural Terminology codes 29882 and 29883) were identified using the PearlDiver Patient Record Database, which is a national database of insurance records. The authors identified 187,607 arthroscopic medial or lateral meniscectomies and repairs performed between 2004 and 2009. Ninety-six percent of patients underwent meniscectomy and 4% underwent repair. No change occurred in the incidence of medial or lateral meniscectomy. The incidence of medial meniscus repair decreased from 5.3 cases per 10,000 patients in 2004 to 3.8 in 2009 (P<.001), although no significant change occurred in the incidence of lateral meniscus repair. Medial meniscectomy was most commonly performed in patients aged 50 to 59 years, whereas lateral meniscectomy demonstrated a bimodal age distribution. Conversely, meniscus repairs were most frequently performed in patients aged 10 to 19 years. Sex differences were more pronounced with meniscus repair (63% male vs 37% female) compared with meniscectomy (53% male vs 47% female). A high frequency of meniscus debridement can be expected in arthroscopic knee surgery. Despite advances in meniscus repair techniques and devices, no increase occurred in the performance of meniscus repair compared with meniscectomy.

A comparative study of meniscectomy and nonoperative treatment for degenerative horizontal tears of the medial meniscus

BACKGROUND

It is still debated whether a degenerative horizontal tear of the medial meniscus should be treated with surgery.

HYPOTHESIS

The clinical outcomes of arthroscopic meniscectomy will be better than those of nonoperative treatment for a degenerative horizontal tear of the medial meniscus.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 102 patients with knee pain and a degenerative horizontal tear of the posterior horn of the medial meniscus on magnetic resonance imaging were included in this study between January 2007 and July 2009. The study included 81 female and 21 male patients with an average age of 53.8 years (range, 43-62 years). Fifty patients underwent arthroscopic meniscectomy (meniscectomy group), and 52 patients underwent nonoperative treatment with strengthening exercises (nonoperative group). Functional outcomes were compared using a visual analog scale (VAS) for pain, Lysholm knee score, Tegner activity scale, and patient subjective knee pain and satisfaction. Radiological evaluations were performed using the Kellgren-Lawrence classification to evaluate osteoarthritic changes.

RESULTS

In terms of clinical outcomes, meniscectomy did not provide better functional improvement than nonoperative treatment. At the final follow-up, the average VAS scores were 1.8 (range, 1-5) in the meniscectomy group and 1.7 (range, 1-4) in the nonoperative group (P = .675). The average Lysholm knee scores at 2-year follow-up were 83.2 (range, 52-100) and 84.3 (range, 58-100) in the meniscectomy and nonoperative groups, respectively (P = .237). In addition, the average Tegner activity scale and subjective satisfaction scores were not significantly different between the 2 groups. Although most patients initially had intense knee pain with mechanical symptoms, both groups reported a relief in knee pain, improved knee function, and a high level of satisfaction with treatment (P < .05 for all values). Two patients in the meniscectomy group and 3 in the nonoperative group with Kellgren-Lawrence grade 1 progressed to grade 2 at the 2-year follow-up.

CONCLUSION

There were no significant differences between arthroscopic meniscectomy and nonoperative management with strengthening exercises in terms of relief in knee pain, improved knee function, or increased satisfaction in patients after 2 years of follow-up.

The incidence of secondary pathology after anterior cruciate ligament rupture in 5086 patients requiring ligament reconstruction

We reviewed 5086 patients with a mean age of 30 years (9 to 69) undergoing primary reconstruction of the anterior cruciate ligament (ACL) in order to determine the incidence of secondary pathology with respect to the time between injury and reconstruction. There was an increasing incidence of medial meniscal tears and chondral damage, but not lateral meniscal tears, with increasing intervals before surgery. The chances of requiring medial meniscal surgery was increased by a factor of two if ACL reconstruction was delayed more than five months, and increased by a factor of six if surgery was delayed by > 12 months. The effect of delaying surgery on medial meniscal injury was also pronounced in the patients aged < 17 years, where a delay of five to 12 months doubled the odds of medial meniscal surgery (odds ratio (OR) 2.0, p = 0.001) and a delay of > 12 months quadrupled the odds (OR 4.3, p = 0.001). Increasing age was associated with a greater odds of chondral damage (OR 4.6, p = 0.001) and medial meniscal injury (OR 2.9, p = 0.001), but not lateral meniscal injury. The gender split (3251 men, 1835 women) revealed that males had a greater incidence of both lateral (34% (n = 1114) vs 20% (n = 364), p = 0.001) and medial meniscal tears (28% (n = 924) vs 25% (n = 457), p = 0.006), but not chondral damage (35% (n = 1152) vs 36% (n = 665), p = 0.565). We conclude that ideally, and particularly in younger patients, ACL reconstruction should not be delayed more than five months from injury.

Finnish Degenerative Meniscal Lesion Study (FIDELITY): a protocol for a randomised, placebo surgery controlled trial on the efficacy of arthroscopic partial meniscectomy for patients with degenerative meniscus injury with a novel 'RCT within-a-cohort' study design

INTRODUCTION

Arthroscopic partial meniscectomy (APM) to treat degenerative meniscus injury is the most common orthopaedic procedure. However, valid evidence of the efficacy of APM is lacking. Controlling for the placebo effect of any medical intervention is important, but seems particularly pertinent for the assessment of APM, as the symptoms commonly attributed to a degenerative meniscal injury (medial joint line symptoms and perceived disability) are subjective and display considerable fluctuation, and accordingly difficult to gauge objectively.

METHODS AND ANALYSIS

A multicentre, parallel randomised, placebo surgery controlled trial is being carried out to assess the efficacy of APM for patients from 35 to 65 years of age with a degenerative meniscus injury. Patients with degenerative medial meniscus tear and medial joint line symptoms, without clinical or radiographic osteoarthritis of the index knee, were enrolled and then randomly assigned (1 : 1) to either APM or diagnostic arthroscopy (placebo surgery). Patients are followed up for 12 months. According to the prior power calculation, 140 patients were randomised. The two randomised patient groups will be compared at 12 months with intention-to-treat analysis. To safeguard against bias, patients, healthcare providers, data collectors, data analysts, outcome adjudicators and the researchers interpreting the findings will be blind to the patients' interventions (APM/placebo). Primary outcomes are Lysholm knee score (a generic knee instrument), knee pain (using a numerical rating scale), and WOMET score (a disease-specific, health-related quality of life index). The secondary outcome is 15D (a generic quality of life instrument). Further, in one of the five centres recruiting patients for the randomised controlled trial (RCT), all patients scheduled for knee arthroscopy due to a degenerative meniscus injury are prospectively followed up using the same protocol as in the RCT to provide an external validation cohort. In this article, we present and discuss our study design, focusing particularly on the internal and external validity of our trial and the ethics of carrying out a placebo surgery controlled trial.

ETHICS AND DISSEMINATION

The protocol has been approved by the institutional review board of the Pirkanmaa Hospital District and the trial has been duly registered at ClinicalTrials.gov. The findings of this study will be disseminated widely through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION

ClinicalTrials.gov, number NCT00549172.

Epidemiology of osteoarthritis

Osteoarthritis (OA) is the most common form of arthritis in the United States and is a leading cause of disability. It is typically defined in epidemiologic studies by radiographic findings and consideration of symptoms. Its incidence and prevalence are rising, likely related to the aging of the population and increasing obesity. Risk factors for OA include numerous person-level factors, such as age, sex, obesity, and genetics, as well as joint-specific factors that are likely reflective of abnormal loading of the joints. In studying OA, several methodologic challenges exist that can hamper our ability to identify pertinent relationships.

Comparison of gait and pathology outcomes of three meniscal procedures for induction of knee osteoarthritis in sheep

OBJECTIVE(S)

Meniscectomy (MX) of sheep induces a well-established animal model of human osteoarthritis (OA). This study compared the clinical (lameness) and pathological outcomes of unilateral, complete medial MX vs two less traumatic and more easily performed meniscal destabilisation procedures.

METHODS

Four-year old wethers (n = 6/group) underwent sham operation, cranial pole release (CPR), mid-body transection (MBT) or total MX of the medial meniscus. Joints were assessed for gross pathology (cartilage erosion and osteophytes), histomorphometry, two histopathology scoring methods (modified Mankin-type and Pritzker score), and immunohistology for ADAMTS- and MMP-cleaved neoepitopes, at 12 weeks post-op. Ground reaction forces (GRFs) were determined by force plate in a subset (n = 4/group) at baseline, 2.5, 8, and 12 weeks post-op.

RESULTS

Gross pathology scores of operated groups differed significantly from sham animals (P < 0.05) but not from each other, though qualitative differences were noted: CPR sheep developed more cranial and focal lesions, while MBT and MX joints showed more widespread lesions and osteophyte formation. Similarly, histopathology scores were significantly elevated vs sham but did not differ between operated groups at P < 0.05, except for a trend for lower tibial cartilage histopathology in MBT consistent with the immunohistologic pattern of reduced aggrecanase-cleavage neoepitope in that model. CPR sheep developed less femoral subchondral sclerosis, suggesting some residual biomechanical effect from the destabilised but intact meniscus. Few significant differences were noted between operated groups in force plate analyses, though gait abnormalities appeared to be least in CPR sheep, and most persistent (>12 weeks) in MBT animals.

CONCLUSION

The well-validated ovine MX model and the simpler meniscal destabilisation procedures resulted in broadly similar joint pathology and lameness. Meniscal CPR or MBT, as easier and more clinically relevant procedures, may represent preferred models for the induction of OA and evaluation of potential disease-modifying therapies.

A 12-week exercise therapy program in middle-aged patients with degenerative meniscus tears: a case series with 1-year follow-up

STUDY DESIGN

Case series.

BACKGROUND

Exercise is a viable treatment alternative to arthroscopic partial meniscectomy in patients with degenerative meniscus tears. No study has reported in detail the type of exercises, progression, tolerance, and potential benefit from an exercise therapy program in these patients who have not had surgery. This case report describes a progressive exercise therapy program aimed at improving neuromuscular function and muscle strength in middle-aged patients with degenerative meniscus tears, the outcome over a 12-week period, and the ability to maintain improvements up to 1 year.

CASE DESCRIPTION

The first 20 patients (age range, 38-58 years) included in an ongoing randomized controlled trial.

OUTCOMES

Outcomes data included the Knee injury and Osteoarthritis Outcome Score, a 7-point global rating of change scale, isokinetic knee muscle strength tests, and 3 lower extremity performance tests. Postintervention, 16 of 20 patients showed clinically meaningful changes (greater than 10 points) on the Knee injury and Osteoarthritis Outcome Score knee-related quality of life subscale, 19 of 20 patients rated themselves as "a lot better" or "better" on the global rating of change scale, all patients had increased quadriceps muscle strength, and the majority of patients improved on the lower extremity performance tests. At 1 year postintervention, the majority of patients had maintained the improvements and none of the patients had undergone surgery.

DISCUSSION

The described neuromuscular- and strength-training program should be considered for rehabilitation of middle-aged individuals with degenerative meniscus tears. However, head-to-head comparison of programs in a randomized design is needed to determine if this specific program is significantly better than other interventions.

Meniscectomy

To review the meniscus from a historical perspective especially on surgical management and general guidelines for arthroscopic meniscectomy procedures for various types of meniscal tears. We searched MEDLINE and PubMed for the years of 1980-2010 using the terms meniscus, meniscal repair, menisectomy, and arthroscopy. Orthopedic surgeons frequently encounter patients with pain or functional impairment of the knee joint and repair or resection of the injured meniscus is one of the most common orthopedic operative procedures. The object of meniscal surgery is to reduce pain, restore functional meniscus and prevent the development of degenerative osteoarthritis in the involved knee. Historically, total meniscectomy was a common procedure performed for meniscus tear symptoms. However, it has been reported that total meniscectomy has deleterious effects on the knee. In the past, the menisci were thought as a functionless remnant tissue. Currently, it is known that the meniscus is an important structure for knee joint function. Menisci provide several vital functions including mechanical support, localized pressure distribution, and lubrication to the knee joint. It is widely accepted that the function of the meniscus can be preserved through minimal excision. An arthroscopic partial meniscectomy preserving more of the meniscus is preferred over total meniscectomy. In recent decades, this shift toward arthroscopic partial meniscectomy has led to the development of new surgical techniques.

Anterior cruciate ligament rupture and osteoarthritis progression

Anterior Cruciate Ligament (ACL) rupture is a common sporting injury that frequently affects young, athletic patients. Apart from the functional problems of instability, patients with ACL deficient knees also develop osteoarthritis. Although this is frequently cited as an indication for ACL reconstruction, the relationship between ACL rupture, reconstruction and the instigation and progression of articular cartilage degenerative change is controversial.The purpose of this paper is to review the published literature with regards ACL rupture and the multifactorial causes for osteoarthritis progression, and whether or not this is slowed or stopped by ACL reconstruction.There is no evidence in the published literature to support the view that ACL reconstruction prevents osteoarthritis, although it may prevent further meniscal damage. It must be recognised that this conclusion is based on the current literature which has substantial methodological limitations.

Changes in self-reported knee function and health-related quality of life after knee injury in female athletes

OBJECTIVE

To document the changes in self-reported health-related quality of life and knee function in a cohort of young female athletes who have sustained a knee injury.

DESIGN

Prospective cohort.

SETTING

An outpatient sports medicine clinic and university student health service.

PARTICIPANTS

A convenience sample of 255 females (age = 17.4 ± 2.4 years) who injured their knee participating in sport or recreational activities. Injuries were categorized as anterior cruciate ligament tears, anterior knee pain, patellar instability, meniscus tear, collateral ligament sprain, and other.

INTERVENTIONS

Knee function was assessed with the 2000 International Knee Documentation Committee (IKDC) knee survey. Health-related quality of life was assessed with the SF-12 version 2.0 (acute) survey (SF-12).

MAIN OUTCOME MEASURES

Dependent variables included the paired differences in the 2000 IKDC and SF-12 subscales, and composite scores from preinjury to diagnosis. Paired differences were assessed with paired t tests (P < 0.05) reported as the mean ± SD.

RESULTS

International Knee Documentation Committee scores at diagnosis were significantly lower than preinjury scores (P < 0.001). SF-12 scores were lower (P < 0.001) at diagnosis for each subscale (physical functioning, role physical, bodily pain, general health, vitality, social function, role emotional, and mental health) as well as the physical and mental composite scores.

CONCLUSIONS

In addition to negatively affecting knee function, sport medicine providers should be aware that knee injuries can negatively impact the health-related quality of life in these athletes immediately after injury.

Muscle strength and functional performance in patients at high risk of knee osteoarthritis: a follow-up study

PURPOSE

To investigate whether changes from 2 to 4 years post arthroscopic partial meniscectomy (APM) in mechanical muscle function and objectively measured function differ between the operated and contra-lateral leg of APM patients or compared with controls.

METHODS

Twenty-two patients (age 46.6 ± 5.0, BMI 24.7 ± 2.9) and 25 controls (age 46.4 ± 5.2, BMI 25.1 ± 4.6) previously examined at ~2 years post APM were examined again at ~4 years post surgery for maximal knee extensor/flexor voluntary contraction (MVC) and rapid force capacity. Functional performance was assessed by the distance achieved during a one-leg hop test and the maximum number of knee bends performed in 30 s. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was used to evaluate self-reported outcomes.

RESULTS

Overall changes from 2 to 4 years post APM did not differ in maximal muscle strength, rapid force capacity, and functional performance between the operated and contra-lateral leg of patients or control legs. However, secondary analysis showed a difference in change in knee extensor MVC resulting in a 6% difference between the operated and contra-lateral leg of patients at follow-up.

CONCLUSIONS

No differences in longitudinal changes were observed from 2 to 4 years post APM between patients and controls. The secondary finding of differential changes over time in knee extensor MVC between the operated and contra-lateral leg partly confirm our hypothesis that differences in muscle strength may evolve from 2 to 4 years post APM. This differential change may represent an initial sign of an evolving lower limb muscle asymmetry, which may play a role in the development of knee OA.

LEVEL OF EVIDENCE

III.

Successful treatment of painful irreparable partial meniscal defects with a polyurethane scaffold: two-year safety and clinical outcomes

BACKGROUND

A novel, biodegradable, polyurethane scaffold was designed to fulfill an unmet clinical need in the treatment of patients with painful irreparable partial meniscal defects.

HYPOTHESIS

The use of an acellular polyurethane scaffold for new tissue generation in irreparable partial meniscal defects provides both pain relief and improved functionality.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Fifty-two patients with irreparable partial meniscal defects (34 medial and 18 lateral, 88% with 1-3 previous surgeries on the index meniscus) were implanted with a polyurethane scaffold in a prospective, single-arm, multicenter, proof-of-principle study. Safety was assessed by the rate of scaffold-related serious adverse events (SAEs) and the International Cartilage Repair Society articular cartilage scoring system comparing magnetic resonance imaging (MRI) at 24 months to MRI at baseline (1 week). Kaplan-Meier time to treatment failure distributions were performed. Clinical outcomes were measured comparing visual analog scale, International Knee Documentation Committee, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Lysholm scores at 24 months from baseline (entry into study).

RESULTS

Clinically and statistically significant improvements (P < .0001) compared with baseline were reported in all clinical outcome scores (baseline/24 months): visual analog scale (45.7/20.3), International Knee Documentation Committee (45.4/70.1), KOOS symptoms (64.6/78.3), KOOS pain (57.5/78.6), KOOS activities of daily living (68.8/84.2), KOOS sports (30.5/59.0), KOOS quality of life (33.9/56.6), and Lysholm (60.1/80.7), demonstrating improvements in both pain and function. The incidence of treatment failure was 9 (17.3%) patients, of which 3 patients (8.8%) had medial meniscal defects and 6 patients (33.3%) had lateral meniscal defects. There were 9 SAEs requiring reoperation. Stable or improved International Cartilage Repair Society cartilage grades were observed in 92.5% of patients between baseline and 24 months.

CONCLUSION

At 2 years after implantation, safety and clinical outcome data from this study support the use of the polyurethane scaffold for the treatment of irreparable, painful, partial meniscal defects.

Lower extremity-specific measures of disability and outcomes in orthopaedic surgery

Outcome measures may be simple questions or complex measures that assess multiple interrelated domains affecting treatment outcomes. Outcome measures should be relevant to patients, easy to use, reliable, valid, and responsive to clinical changes. Joint and disease-specific outcome measures have been developed for the hip, knee, and foot and ankle. Many of these measures would benefit from further research into their validity, reliability, and optimal applicability. General health measures and activity level scores should be included in outcome assessments after treatment for orthopaedic conditions.

Meniscus repair and transplantation: a comprehensive update

Preservation of meniscal tissue is paramount for long-term joint function, especially in younger patients who are athletically active. Many studies have reported encouraging results following repair of meniscus tears for both simple longitudinal tears located in the periphery and complex multiplanar tears that extend into the central third avascular region. This operation is usually indicated in active patients who have tibiofemoral joint line pain and are less than 50 years of age. However, not all meniscus tears are repairable, especially if considerable damage has occurred. In select patients, meniscus transplantation may restore partial load-bearing meniscus function, decrease symptoms, and provide chondroprotective effects. The initial postoperative goal after both meniscus repair and transplantation is to prevent excessive weight bearing, as high compressive and shear forces can disrupt healing meniscus repair sites and transplants. Immediate knee motion and muscle strengthening are initiated the day after surgery. Variations are built into the rehabilitation protocol according to the type, location, and size of the meniscus repair, if concomitant procedures are performed, and if articular cartilage damage is present. Meniscus repairs located in the periphery heal rapidly, whereas complex multiplanar repairs tend to heal more slowly and require greater caution. The authors have reported the efficacy of the rehabilitation programs and the results of meniscus repair and transplantation in many studies.

Biomechanical considerations in the pathogenesis of osteoarthritis of the knee

Osteoarthritis is the most common joint disease and a major cause of disability. The knee is the large joint most affected. While chronological age is the single most important risk factor of osteoarthritis, the pathogenesis of knee osteoarthritis in the young patient is predominantly related to an unfavorable biomechanical environment at the joint. This results in mechanical demand that exceeds the ability of a joint to repair and maintain itself, predisposing the articular cartilage to premature degeneration. This review examines the available basic science, preclinical and clinical evidence regarding several such unfavorable biomechanical conditions about the knee: malalignment, loss of meniscal tissue, cartilage defects and joint instability or laxity. Level of evidence IV.

Treatment of meniscus tears during anterior cruciate ligament reconstruction

PURPOSE

To define the incidence of meniscectomy, meniscus repair, and meniscus tears left in situ during anterior cruciate ligament (ACL) reconstruction.

METHODS

A systematic search of PubMed and 7 sports medicine journal databases was performed to determine the treatment of meniscus tears during ACL reconstruction. Inclusion criteria were English language, publication in the last 10 years, clinical trials, all evidence levels, and skeletally mature or immature knees. Exclusion criteria were revision ACL reconstruction, concomitant ligament reconstruction, and studies with exclusion or inclusion criteria regarding meniscus surgery during ACL reconstruction.

RESULTS

Of 634 articles identified, 159 met the inclusion criteria, encompassing 19,531 patients. There were 11,711 meniscus tears; they were treated by meniscectomy in 65% (7,621 tears), treated by repair in 26% (3,022 tears), or left in situ in 9% (1,068 tears). Only 19 studies analyzed the treatment of meniscus tears according to the tibiofemoral compartment. These reported medial compartment tears were treated by meniscectomy in 63%, treated by repair in 27%, and left in situ in 9%. Lateral compartment tears were treated by meniscectomy in 71%, treated by repair in 14%, and left in situ in 14%. Only 24 studies identified the type of meniscus repair procedure performed. In 33 studies (21%) repair was performed more frequently than meniscectomy.

CONCLUSIONS

Meniscectomy is performed 2 to 3 times more frequently than meniscus repair during ACL reconstruction. We were unable to analyze the effect of the location and type of meniscus tear, sex, age, or chronicity of injury on the treatment of meniscus tears. The number of potentially repairable meniscus tears that were treated by resection could not be identified.

CLINICAL RELEVANCE

This study found that meniscectomy was performed in 65% of meniscus tears. This is concerning because studies have shown that, regardless of knee stability obtained after ACL reconstruction, meniscectomy accelerates degenerative joint changes.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I to IV studies.

Anterior cruciate ligament tears: conservative or surgical treatment? A critical review of the literature

PURPOSE

Is it rational to recommend surgical reconstruction of the torn anterior cruciate ligament to every patient? Is conservative management still a valid option?

METHOD

Through a literature review, we looked for the arguments from each side and checked their validity.

RESULTS

Unfortunately results of most studies cannot be compared because of the following reasons not exhaustively cited: studied populations differed with respect to age, sex, professional and sports activity level, lesions associated with ACL rupture, patient recruitment methods, time from injury to treatment and different therapeutic modalities. Furthermore, various methods were used to evaluate the clinical and radiological results and there was no consensus of their interpretation. Some authors assumed that the incidence of further meniscus lesions could probably be reduced if the torn ACL was surgically reconstructed. But, we have no evidence to believe that this would be due to the surgical repair rather than to a decrease of involvement in strenuous activities. At present it is not demonstrated that ACL-plasty can prevent osteoarthritis. Numerous factors could explain evolution to arthrosis whatever the treatment for the ACL-ruptured knee. Studies comparing surgical and conservative treatments confirm that ACL reconstruction is not the pre-requisite for returning to sporting activities. More recent and scientifically well-designed studies demonstrate that conservative treatment could give satisfactory results for many patients. They suggest some methods to help them choose the best treatment.

CONCLUSION

At present there are no evidence-based arguments to recommend a systematic surgical reconstruction to any patient who tore his ACL. Knee stability can be improved not only by surgery but also by neuromuscular rehabilitation. Whatever the treatment, fully normal knee kinematics are not restored. While the patients wish to go back to their sport and want everything possible done to prolong their ability to perform these activities, they should be informed that the risk of further knee lesions and osteoarthritis remains high, whatever the treatment, surgical or conservative.

LEVEL OF EVIDENCE

Systematic review of Level I, II, III and IV studies, Level IV.

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.