The effect of meniscal repair on strength deficits 6 months after ACL reconstruction

Management of Meniscus Pathology with Concomitant Anterior Cruciate Ligament Injury

PURPOSE OF REVIEW

The purpose of this review is to summarize current clinical knowledge on the prevalence and types of meniscus pathology seen with concomitant anterior cruciate ligament (ACL) injury, as well as surgical techniques, clinical outcomes, and rehabilitation following operative management of these pathologies.

RECENT FINDINGS

Meniscus pathology with concomitant ACL injury is relatively common, with reports of meniscus pathology identified in 21-64% of operative ACL injuries. These concomitant injuries have been associated with increased age and body mass index. Lateral meniscus pathology is more common in acute ACL injury, while medial meniscus pathology is more typical in chronic ACL deficiency. Meniscus tear patterns associated with concomitant ACL injury include meniscus root tears, lateral meniscus oblique radial tears of the posterior horn (14%), and ramp lesions of the medial meniscus (8-24%). These meniscal pathologies with concomitant ACL injury are associated with increased rotational laxity and meniscal extrusion. There is a paucity of comparative studies to determine the optimal meniscus repair technique, as well as rehabilitation protocol, depending on specific tear pattern, location, and ACL reconstruction technique. There has been a substantial increase in recent publications demonstrating the importance of meniscus repair at the time of ACL repair or reconstruction to restore knee biomechanics and reduce the risk of progressive osteoarthritic degeneration. Through these studies, there has been a growing understanding of the meniscus tear patterns commonly identified or nearly missed during ACL reconstruction. Surgical management of meniscal pathology with concomitant ACL injury implements the same principles as utilized in the setting of isolated meniscus repair alone: anatomic reduction, biologic preparation and augmentation, and circumferential compression. Advances in repair techniques have demonstrated promising clinical outcomes, and the ability to restore and preserve the meniscus in pathologies previously deemed irreparable. Further research to determine the optimal surgical technique for specific tear patterns, as well as rehabilitation protocols for meniscus pathology with concomitant ACL injury, is warranted.

Influence of Graft Type and Meniscal Involvement on Short-Term Outcomes Following Anterior Cruciate Ligament Reconstruction

CONTEXT

The purpose of this study was to compare short-term clinical outcomes between meniscus procedures performed with anterior cruciate ligament reconstruction (ACLR), ACLR (ACLR-only), ACLR with meniscectomy/resection (ACLR-resect), and ACLR with meniscal repair (ACLR-repair) for bone patellar tendon bone grafts (BPTB) and hamstring tendon grafts, separately.

DESIGN

This was a cross-sectional study conducted in a controlled laboratory setting as part of a large point-of-care collaborative research program.

METHODS

This study included 314 participants (168 females; mean [SD]: age, 19.7 [4.8]) with primary unilateral ACLR with a BPTB or hamstring tendon. Patients were divided into 3 groups depending on meniscal procedure (ACLR-only, ACLR-resect, and ACLR-repair). Postsurgical testing included: isokinetic assessment of knee extension and flexion, single-leg hop tests, and patient-reported outcomes. Multivariate analysis of covariance compared differences between meniscal procedures on the battery of tests, and for each statistically significant variable an analysis of covariance assessed the effect of meniscal procedure within each graft type. Chi-square analysis assessed the influence of meniscal procedure on tests' pass rates defined as 90% of limb symmetry index.

RESULTS

BPTB: ACLR-only had greater hamstring strength than ACLR-resect (P = .05) and ACLR-repair (P = .005). ACLR-only had the highest proportion of participants to pass the hamstring strength test (P = .02). Hamstring tendon: ACLR-only (P = .03) and ACLR-resect (P = .003) had higher International Knee Documentation Committee scale scores than ACLR-repair. There was a significant difference in the proportion of participants who scored >90% limb symmetry index on the timed hop test (P = .05).

CONCLUSIONS

The influence of meniscal repair on clinical outcomes is dependent on the graft choice. Following an ACLR with BPTB and a meniscal procedure, hamstring function should be more closely monitored for optimal short-term recovery.

Return-to-sport criteria after isolated meniscus suture: Scoping review of the literature

BACKGROUND

Follow-up care including rehabilitation therapy after isolated meniscal repair remains to be standardized. Thus, no standard criteria are available for the return-to-running (RTR) or return-to-sport (RTS). The objective of this study was to identify criteria for RTR and RTS after isolated meniscal repair, based on a review of the literature.

HYPOTHESIS

Return-to-sport criteria after isolated meniscal repair have been published.

METHODS

We performed a scoping review of the literature using the methodology developed by Arksey and O'Malley. The terms "menisc*" and "repair" and "return-to-sport" or "return to play" or "return to run" or "rehabilitation" were used to search the PubMed database on 1st March 2021. All relevant studies were included. All RTR and RTS criteria were identified, analyzed, and classified.

RESULTS

We included 20 studies. Mean RTR and RTS times were 12.9 and 20 weeks, respectively. Clinical, strength, and performance criteria were identified. The clinical criteria included full range-of-motion recovery with no pain, quadriceps wasting, or joint effusion. Strength criteria were a quadriceps and hamstring deficit, no greater than 30% and 15% for RTR and RTS, respectively, compared to the normal side. Performance criteria were successful completion of proprioception, balance, and neuromuscular tests. RTS rates ranged from 80.4% to 100%.

CONCLUSION

Patients must meet clinical, strength, and performance criteria before resuming running and sports. The level of evidence is low, due to the heterogeneity and generally arbitrary choice of criteria. Further large-scale studies are therefore needed to validate and standardize RTR and RTS criteria.

LEVEL OF EVIDENCE

IV.

Concentric Isokinetic Strengthening Program's Impact on Knee Biomechanical Parameters, Physical Performance and Quality of Life in Overweight/Obese Women with Chronic Meniscal Lesions

Meniscal injuries are one of the most common intra-articular knee injuries. Different treatments are presented depending on the symptoms and duration of meniscus tears, such as arthroscopic partial meniscectomy, physiotherapy, or even pharmacological treatment. The purpose was to investigate the effect of a concentric isokinetic knee muscle strengthening program on strength, joint range of motion, physical performance, quality of life and pain tolerance in overweight/obese women with chronic meniscal lesions. Twenty-four overweight/obese women were randomized into two groups. A control group (CG) performed a usual rehabilitation program plus isokinetic muscle strengthening (IMS) in the continuous passive motion mode and measured with an isokinetic dynamometer. An experimental group (EG) performed the same program in combination with IMS in the isokinetic active mode. The peak torque of the knee extensors (PTE) and flexors (PTF), sit-to-stand test, stair climb test, joint amplitude, heel-to-buttock distance, Thessaly test, KOOS questionnaire of pain and quality of life were measured pre- and post-protocol. After the intervention, the sit-stand number for both groups was significantly higher (p < 0.001) and the time to climb stairs was significantly reduced for the EG (p < 0.001). A significant improvement in joint range of motion, life quality (p < 0.001), relief in knee pain (p < 0.001) and in the post-program evaluation at the EG (p < 0.05) was noted. There was no significant difference in PTE and PTF between groups at 60°/s and 180°/s. The IMS in the active mode could be an effective therapeutic modality in managing middle-aged patients suffering from a degenerative meniscal tear.

The Impact of Meniscal Tear Type and Surgical Treatment on Quadriceps Strength: A Study of Adolescent Patients Post Anterior Cruciate Ligament Reconstruction

BACKGROUND

Treatment of meniscal injuries at the time of anterior cruciate ligament reconstruction (ACLR) can result in restrictions on weightbearing and range of motion in the early rehabilitative phases. What is unknown is the effect of (1) meniscal tear type and location at the time of anterior cruciate ligament injury and (2) meniscal treatment at the time of ACLR on quadriceps strength in adolescents during the late rehabilitative phase.

HYPOTHESIS

Meniscal tears involving the root and requiring repair would adversely affect quadriceps strength at 6 to 9 months postoperatively.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent ACLR at 1 of 2 research sites between 2013 and 2021 were identified. Adolescent participants were included if they were between the ages of 12 and 20 years at the time of assessment and had undergone primary unilateral ACLR in the previous 6 to 9 months. Participants were subgrouped by meniscal tear type (no tear, nonroot tear, root tear) and meniscal treatment at the time of ACLR (no treatment, meniscectomy, meniscal repair), which were confirmed via chart review. Isokinetic strength testing occurred at 60 deg/s, and quadriceps strength and quadriceps strength limb symmetry index were compared between the meniscal tear type and meniscal procedure subgroups using analysis of covariance while controlling for the effects of age, sex, and ACLR graft source.

RESULTS

An overall 236 patients were included in this analysis (109 male, 127 female; mean ± SD age, 16.0 ± 1.9 years). There were no significant differences in ACLR limb quadriceps strength based on meniscal tear type (P = .61) or meniscal procedure at the time of ACLR (P = .61), after controlling for age, biological sex, and ACLR graft source. Similarly, quadriceps strength limb symmetry index did not differ by meniscal tear type (P = .38) or meniscal procedure at the time of ACLR (P = .40).

CONCLUSION

Meniscal tear type and treatment at the time of ACLR did not affect quadriceps strength or quadriceps strength symmetry in adolescents 6 to 9 months after ACLR.

Etiology of posterior meniscus root tears: medial vs. lateral

PURPOSE

The aim of this study was to generate more information on the etiology and pathogenesis of medial (MM) and lateral (LM) meniscus root tears. Our hypothesis was that root tears of the MM predominantly result from degenerative damage, whereas root injuries of the LM are mainly of traumatic origin.

METHODS

Consecutively, 53 patients with a root tear of the medial meniscus (MMRT) and 51 patients with a root tear of the lateral meniscus (LMRT) were included in this study. The diagnosis was confirmed radiologically by MRI as well as arthroscopically. In addition to patient-specific data such as age, BMI and trauma history, the leg axis was determined and accompanying injuries (ligamentous and chondrogenic) were documented.

RESULTS

The mean age of the MMRT group was 57.2 (± 11.2) years, and that of the LMRT group 33.9 (± 11.4) years. The BMI was significantly higher in the MMRT group compared to the LMRT (30.5 vs. 25.1). 82.4% of patients in the LMRT group demonstrated an accompanying anterior cruciate ligament (ACL) rupture, whereas only 5.7% of the MMRT were associated with an ACL injury. A trauma was described in only 13.2% of patients of the MMRT group in contrast to 88.2% of the LMRT group. An extrusion > 3 mm of the MM in the coronal plane of MRI images could be detected in 86.8% of patients, whereas in the LMRT group, it was 15.7%. The mechanical varus angle was 5.6° in the MMRT group and 2.4° in the LMRT group. The rate and degree of concomitant cartilage damage in the affected compartment was significantly higher in the group with medial root injuries than in the group with lateral root tears.

CONCLUSIONS

The root injuries of the MM and LM show significant differences in terms of patient age, etiology and accompanying injuries. Root injuries to the medial meniscus are mostly of non-traumatic origin and more likely to occur in the context of medial osteoarthritis and varus deformity of the knee. Lateral root tears tend to be predominantly traumatic and are frequently associated with ACL ruptures. However, in the MMRT group, a small subgroup with a traumatic etiology and in the LMRT group a small subgroup of patients with non-traumatic etiology could be identified.

LEVEL OF EVIDENCE

III.

General, spinal or regional anaesthesia does not affect strength performance 6 months after ACL reconstruction

PURPOSE

The recovery of strength is a key element in successfully returning to sports after ACL reconstruction. The type of anaesthesia has been suspected an influential factor in the post-operative recovery of muscle function.

METHODS

In this retrospective analysis, n = 442 consecutive patients undergoing primary isolated ACL reconstruction using a hamstring autograft were analysed by pre- and post-operative isokinetic tests in a single orthopaedic centre. These were subdivided into four cohorts: (1) general anaesthesia (n = 47), (2) general anaesthesia with prolonged (48 h) on-demand femoral nerve block (n = 37), (3) spinal anaesthesia (n = 169) and (4) spinal anaesthesia with prolonged (48 h) on-demand femoral nerve block (n = 185). Primary outcome was the change from pre- to post-operative isokinetic strength during knee extension and flexion.

RESULTS

Using one-way ANOVA, there was no significant influence of the type of anaesthesia. The main effect of anaesthesia on change in extension forces was not significant, and effect sizes were very small (n.s.). Similarly, the main effect of anaesthesia on change in flexion forces was statistically not significant (n.s.).

CONCLUSIONS

The findings of this study support the interpretation that the type of anaesthesia has no significant effect on the ability to recover thigh muscle strength 6 months after isolated hamstring ACL reconstruction. With regard to the recovery of athletic performance and return-to-sports testing criteria, there is no reason to avoid regional anaesthesia.

LEVEL OF EVIDENCE

III.

High quality rehabilitation to optimize return to sport following lateral meniscus surgery in football players

There is a paucity of studies in the literature pertaining about how to guide rehabilitation and return to sport (RTS) progression for football players that have sustained a lateral meniscus injury and subsequent surgery. These patients are clinically challenging. If they return to sport too soon, before the rehabilitation process is completed and RTS criteria have been met, functional outcomes could be non-optimal and/or associated with higher reinjury risk. The aims of this paper are (I) to provide a brief overview of the current trends in acute lateral meniscus tears surgery in football players and (II) to suggest a framework for clinicians on how to progress the player following lateral meniscus surgery. Post-operative rehabilitation approaches are different for meniscus repair and for the other surgical techniques. The main goal of all involved practitioners should be to balance the "short term success" with the "long term protection" of the athlete's health. Specific key goals and interventions in early-, mid-, and late-stage rehabilitation are provided. The most important principle is to manage the progressive increase in loading through multiple measurements including frequent medical control consultations and functional tests detailing movement quantity and quality. RTS monitoring needs to be comprehensive and interdisciplinary, incorporating state of the art tests, to achieve recovery of sport-specific fitness, optimal movement quality and on-field rehabilitation progression.

Novel press-fit technique of patellar bone plug in anterior cruciate ligament reconstruction is comparable to interference screw fixation

PURPOSE

Conventional press-fit technique for anterior cruciate ligament reconstruction (ACLR) is performed with extraction drilling of the femoral bone tunnel and manual shaping of the patellar bone plug. However, the disadvantages of this technique include variation in bone plug size and, thus, the strength of the press-fit fixation, bone loss with debris distribution within the knee joint, potential heat necrosis, and metal wear debris due to abrasion of the guide wire. To overcome these disadvantages, a novel technique involving punching of the femoral bone tunnel and standardized compression of the bone plug was introduced. In this study, the fixation strength and apparent stiffness were tested and compared to that of the gold-standard interference screw fixation technique in three flexion angle configurations (0°/45°/90°) in a porcine model. We hypothesized that the newly developed standardized press fit fixation would not be inferior to the gold standard method.

METHODS

Sixty skeletally mature porcine knees (30 pairs) were used. Full-thickness central third patellar tendon strips were harvested, including a patellar bone cylinder of 9.5 mm in diameter. The specimens were randomly assigned to 10 pairs per loading angle (0°, 45°, 90°). One side of each pair was prepared with the press-fit technique, and the contra-lateral side was prepared with interference screw fixation. Equivalent numbers of left- and right-sided samples were used for both fixation systems. A three-way multifactor ANOVA was carried out to check for the influence of (a) fixation type, (b) flexion angle, and (c) side of the bone pair.

RESULTS

The primary fixation strength of femoral press-fit graft fixation with punched tunnels and standardized bone plug compression did not differ significantly from that of interference screw fixation (p = 0.51), which had mean loads to failure of 422.4 ± 134.6 N and 445.4 ± 135.8 N, respectively. The flexion angle had a significant influence on the maximal load to failure (p = 0.01). Load values were highest in 45° flexion for both fixations. The anatomical side R/L was not a statistically significant factor (p = 0.79).

CONCLUSION

The primary fixation strength of femoral press-fit graft fixation with punched femoral tunnels and standardized bone plug compression is equivalent to that of interference screw fixation in a porcine model. Therefore, the procedure represents an effective method for ACL reconstruction with patellar or quadriceps tendon autografts including a patellar bone plug.

Does meniscal repair impact muscle strength following ACL reconstruction?

Purpose: Meniscal lesions are commonly associated with anterior cruciate ligament (ACL) rupture. Meniscal repair, when possible, is widely accepted as the standard of care. Despite advancements in surgical and rehabilitation techniques, meniscal repair may impact muscle recovery when performed in conjunction with ACL reconstruction. The objective of this study was to explore if meniscal repairs in the context of ACL reconstruction affected muscle recovery compared to isolated ACL reconstruction. Methods: Fifty-nine patients with isolated ACL reconstruction were compared to 35 patients with ACL reconstruction with an associated meniscal repair. All ACL reconstructions were performed using hamstring grafts with screw-interference graft fixation. Isokinetic muscle testing was performed between six and eight months of follow-up. Muscle recovery between both groups was compared. A further subgroup analysis was performed to compare muscle recovery function of gender and meniscal tear location. Tegner scores were assessed at six months’ follow-up. Results: No significant differences were found between the two groups regarding muscle recovery. No difference in muscle recovery was found concerning gender. Lesion of both menisci significantly increased the deficit of hamstrings muscular strength at 60°/s compared to a lesion of one meniscus (26.7% ± 15.2 vs. 18.1% ± 13.5, p = 0.018) and in eccentric test (32.4% ± 26.2 vs. 18.1% ± 13.5, p = 0.040). No significant differences were found concerning the Tegner score. Conclusion: Meniscal repairs performed during an ACL reconstruction do not impact muscle recovery at 6–8 months post-operatively compared to an isolated ACL reconstruction. However, reparations of both menisci appear to impact hamstring muscle recovery negatively.

Level of evidence: III, Retrospective cohort study

Preoperative quadriceps muscle strength deficit severity predicts knee function one year after anterior cruciate ligament reconstruction

Quadriceps strength is critical for patients with anterior cruciate ligament (ACL) reconstruction; however, little is known about the relationship between preoperative quadriceps strength deficit and postoperative subjective knee functions. The study aimed to investigate the relationship between preoperative quadriceps strength and postoperative knee function in patients after ACL reconstruction. Seventy-five male patients with primary ACL reconstruction surgery with hamstring autografts between 2014 and 2017 were included. An isokinetic dynamometer assessed quadriceps strength while self-reported knee functions were measured by the International Knee Documentation Committee (IKDC) and Lysholm scores at baseline and 1 year after surgery. The three identified groups (Q1-Q3) were classified according to the preoperative quadriceps muscle strength deficit. Q1 were patients with < 25% quadriceps muscle strength deficit, Q2 showed a 25-45% deficit, and Q3 included those with a deficit > 45%. We compared knee functions between the three groups and examined the associations between preoperative variables and functional knee outcomes. The preoperative quadriceps muscle strength deficit had a negative association with the knee functional scores at 1 year follow-up including the IKDC score (r_s = - 0.397, p = 0.005) and the Lysholm score (r_s = - 0.454, p < 0.001), but not other factors. Furthermore, only the Q1 group, with < 25% deficit in preoperative quadriceps muscle strength, showed a significant correlation in postoperative IKDC score (r = - 0.462, p = 0.030), and Lysholm score (r = - 0.446, p = 0.038). Preoperative quadriceps muscle strength deficit had a significant negative relationship with postoperative function at 1 year following ACL reconstruction.

Isokinetic torque analysis demonstrates deficits in knee flexor and extensor torque in patients at 9-12 months after anterior cruciate ligament reconstruction, despite peak torque symmetry

BACKGROUND

Lower limb strength asymmetry is associated with re-injury after anterior cruciate ligament reconstruction (ACLR). This study investigated limb symmetry indices (LSIs) during isokinetic knee extensor and flexor assessment after ACLR.

METHODS

Overall, 25 patients underwent isokinetic knee extensor and flexor strength assessment, 9-12 months after ACLR with a semitendinosus autograft. While patients were included if they presented with peak knee extensor (PKET) and flexor (PKFT) torque LSIs ≥ 90%, LSIs were calculated at designated points throughout the isokinetic torque range of motion, including: 15°, 30°, 45°, 60° and 75° (from 90° of knee flexion) during PKET and 15°, 30°, 45°, 60° and 75° (from full knee extension) during PKFT. T-tests investigated limb differences for PKET and PKFT, as well as at the final 75° assessment point during knee extension and flexion, between: (1) males and females, (2) those that did, or did not, undergo meniscal surgery, and (3) those undergoing ACLR on their dominant or non-dominant limb.

RESULTS

Significant differences between limbs were observed for PKET at 15° (p = 0.040) and 75° (p = 0.002), and for PKFT at 60° (p = 0.001) and 75° (p < 0.0001). No comparative differences (p > 0.05) were seen based on gender, meniscal surgery or whether ACLR was on the dominant or non-dominant limb.

CONCLUSION

Despite 100% of patients demonstrating PKET and PKFT LSIs ≥ 90%, LSI differences existed at designated points throughout the knee extensor and flexor torque range of motion. Analysis of torques throughout full range should be considered in future studies, as comparison of isolated peak measures miss strength deficits.

Predictive factors for failure of anterior cruciate ligament reconstruction via the trans-tibial technique

INTRODUCTION

Factors for graft failure after trans-tibial (TT) ACL reconstruction, including anterolateral ligament (ALL) injury and degree of synovialization, remain unclear. This study is to evaluate the risk factors for graft failures after TT ACL reconstruction including ALL injury and synovialization.

MATERIALS AND METHODS

A total 391 patients who underwent primary TT ACL reconstruction were included. Failure was defined as greater than grade 2 laxity on the Lachman or pivot shift tests or 5 mm of anterior translation on stress radiograph. After applying inclusion/exclusion criteria, 31 patients with failure were categorized as group 1 and 89 patients without failure were categorized as group 2. Chi-square test and Cox proportional hazard analyses were performed.

RESULTS

Preoperatively, 64 patients had ALL injuries (53.3%), 58 had medial meniscal (MM) tears (48.3%), and 62 had lateral meniscal (LM) tears (51.6%). Ninety-three patients (77.5%) had acute injuries and 27 had chronic injuries as per 6-weeks duration. Significant risk factors for failure were LM tear (hazard ratio [HR], 4.018; 95% confidence interval [CI] 1.677-9.629; p = 0.002), chronicity (HR, 6.812; 95% CI 2.758-16.824; p = 0.000), presence of ALL injury (HR, 3.655; 95% CI 1.442-9.265; p = 0.006), and poor synovialization (HR, 3.134; 95% CI 1.298-7.566; p = 0.011) in Cox proportional hazard analysis. If combined MM and LM tears were found, an increased risk of failure was also identified (combined tears: HR, 3.951; 95% CI 1.754-8.901; p = 0.001/preoperative high-grade laxity: HR, 4.546; 95% CI 1.875-11.02; p = 0.001).

CONCLUSION

Chronic ACL injuries, meniscus tear, preoperative ALL injuries, preoperative high-grade laxity and poor synovialization are significant risk factors. Therefore, these factors should be carefully assessed and properly treated in TT ACL reconstruction.

LEVEL OF EVIDENCE

IV, retrospective cohort study.