Treatment of Patellofemoral Instability and Chondral Lesions.

Lateral patellar instability is one of the most common knee disorders among adolescents. Numerous anthropometric features, including trochlear dysplasia, patella alta, high tibial tubercle-to-trochlear groove distance, and coronal and rotational plane malalignment, are considered primary risk factors for patellar dislocation, and the understanding of their complex interplay is continuously evolving. Because of the multifactorial nature of patellar instability, there is a lack of consensus regarding many aspects of surgical intervention. Medial patellofemoral ligament reconstruction is considered to be the essential procedure in preventing recurrent instability. However, there is growing interest in addressing underlying anatomic risk factors that contribute to patellar instability. It is important to discuss the diagnosis and management of patellar instability, surgical considerations in medial patellofemoral ligament reconstruction, mitigation/correction of anatomic risk factors, and treatment of associated chondral lesions.

Meniscus Extrusion, Radial Tears, and Root Tears.

Management of meniscal radial and root tears and extrusion is complex and has changed significantly over recent years. It is important to provide a comprehensive overview of the management of radial and root tears and meniscal extrusion and be aware of the currently available evidence on repair techniques, rehabilitation, and outcomes following radial and root repairs.

Early- and Late-Stage Benefits of Blood Flow Restriction Training on Knee Strength in Adolescents After Anterior Cruciate Ligament Reconstruction.

Background: Blood flow restriction training (BFRT) after anterior cruciate ligament reconstruction (ACLR) is rising in popularity because of its benefits in reducing muscle atrophy and mitigating knee strength deficits. Purpose: To investigate the impact BFRT has on adolescent knee strength after ACLR at 2 postoperative time points: at 3 months and the time of return to sport (RTS). Study Design: Cohort study; Level of evidence, 3. Methods: A prospective intervention (BFRT) group was compared to an age-, sex-, and body mass index-matched retrospective control group. Patients aged 12 to 18 years who underwent primary ACLR with a quadriceps tendon autograft were included. Along with a traditional rehabilitation protocol, the BFRT group completed a standardized BFRT protocol (3 BFRT exercises performed twice weekly for the initial 12 weeks postoperatively). Peak torque values for isometric knee extension and flexion strength (at 3 months and RTS) and isokinetic strength at 180 deg/s (at RTS) as well as Pediatric International Knee Documentation Committee (Pedi-IKDC) scores were collected. Differences between the BFRT and control groups were compared with 2-way mixed analysis of variance and 1-way analysis of variance. Results: The BFRT group consisted of 16 patients (10 female; mean age, 14.84 ± 1.6 years) who were matched to 16 patients in the control group (10 female; mean age, 15.35 ± 1.3 years). Regardless of the time point, the BFRT group demonstrated significantly higher isometric knee extension torque compared to the control group (2.15 ± 0.12 N·m/kg [95% CI, 1.90-2.39] vs 1.74 ± 0.12 N·m/kg [95% CI, 1.49-1.98], respectively; mean difference, 0.403 N·m/kg; P = .024). The BFRT group also reported significantly better Pedi-IKDC scores compared to the control group at both 3 months (68.91 ± 9.68 vs 66.39 ± 12.18, respectively) and RTS (89.42 ± 7.94 vs 72.79 ± 22.81, respectively) (P = .047). Conclusion: In adolescents, the addition of a standardized BFRT protocol to a traditional rehabilitation protocol after ACLR significantly improved knee strength and patient-reported function compared to a traditional rehabilitation program alone.

A modified Delphi consensus statement on patellar instability: part II.

Aims: The aim of this study was to establish consensus statements on medial patellofemoral ligament (MPFL) reconstruction, anteromedialization tibial tubercle osteotomy, trochleoplasty, and rehabilitation and return to sporting activity in patients with patellar instability, using the modified Delphi process. Methods: This was the second part of a study dealing with these aspects of management in these patients. As in part I, a total of 60 surgeons from 11 countries contributed to the development of consensus statements based on their expertise in this area. They were assigned to one of seven working groups defined by subtopics of interest. Consensus was defined as achieving between 80% and 89% agreement, strong consensus was defined as between 90% and 99% agreement, and 100% agreement was considered unanimous. Results: Of 41 questions and statements on patellar instability, none achieved unanimous consensus, 19 achieved strong consensus, 15 achieved consensus, and seven did not achieve consensus. Conclusion: Most statements reached some degree of consensus, without any achieving unanimous consensus. There was no consensus on the use of anchors in MPFL reconstruction, and the order of fixation of the graft (patella first versus femur first). There was also no consensus on the indications for trochleoplasty or its effect on the viability of the cartilage after elevation of the osteochondral flap. There was also no consensus on postoperative immobilization or weightbearing, or whether paediatric patients should avoid an early return to sport.

Meniscus Size Differs Between Patient and Donor Populations for Meniscus Allograft Transplantation.

Purpose: To determine the extent of variability in meniscus size and anthropometric data between donors (supply) and patients (demand), to evaluate potential factors that may contribute to size discrepancies, and to determine whether the discrepancies lead to longer patient wait times. Methods: Lateral and medial meniscal measurements, anthropometric data, and time to match a donor graft were extracted from a tissue supplier database. The frequency and distribution of meniscus size were analyzed. Body mass index (BMI), relative meniscus area, body mass to meniscus area index, and height to meniscus area index were compared between patient and donor pools via χ2 tests and independent samples t-test. The effect of size on time to match was analyzed using analysis of variance and post-hoc Tukey test. Results: The lateral meniscus patient population showed a greater frequency of larger size requirements compared to the donor population (P < .001) and the medial meniscus patient population showed a higher frequency of smaller meniscus size requirements (P < .001). The medial meniscus analysis showed significantly smaller meniscus areas (P < .001) in the patient population contributing to the observed trend of an increased body mass to meniscus area index and height to meniscus area index. The time to match a donor meniscus was affected by the patient meniscus size. Conclusions: This analysis demonstrates variations in frequency of meniscus sizes between donor and patient populations. This variation is attributed to differences in anthropometric data between patient and donor populations. This work identifies a mismatch between demand and supply for certain patient sizes contributing to longer times to match. Clinical Relevance: This work associated donor and patient mismatches with longer wait times. This can be useful for patient counseling as well as provide a framework to determine whether there are solutions within the current meniscus donor pool that can be used to meet this clinical need.

Discoid Lateral Meniscus.

PURPOSE OF REVIEW: Discoid lateral meniscus (DLM) is a well-known meniscus variant, and comprises excess and thickened meniscal tissue, altered collagen ultrastructure, and peripheral instability. This article presents a comprehensive review on current knowledge of DLM, focusing on pathology in parallel with surgical techniques and outcomes. RECENT FINDINGS: A paradigm shift in surgical management of DLM is taking place as knee surgeons are seeing more patients with long-term sequelae of partial lateral meniscectomy, the standard treatment for DLM for many years. Surgical treatment has evolved alongside the understanding of DLM pathology. A new classification system has been proposed and optimal surgical techniques described in recent years. This article highlights up-to-date evidence and techniques in management of both acute DLM tears and joint restoration following subtotal meniscectomy for DLM. Surgical management of DLM must be tailored to individual pathology, which is variable within the diagnosis of DLM. We present an algorithm for management of DLM and discuss future directions for the understanding and treatment of this debilitating condition.

Unpacking the Tibial Tubercle-Trochlear Groove Distance: Evaluation of Rotational Factors, Trochlear Groove and Tibial Tubercle Position, and Role of Trochlear Dysplasia.

BACKGROUND: The tibial tubercle to trochlear groove (TT-TG) distance is often utilized for determining the surgical treatment for patients with patellar instability (PI). It is thought to directly represent the position of the TT on the tibia. Recent work has shown that the measurement of the TT-TG distance is multifactorial. PURPOSE: To investigate the relationship between relative tibial external rotation (rTER) and trochlear dysplasia (TD), as well as the location of the TG and TT in patients with and without PI, and to correlate these and other anatomic measurements with the TT-TG distance. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 89 patients with PI who underwent magnetic resonance imaging were identified with 92 matched control patients. A standardized measurement protocol on axial magnetic resonance imaging determined rTER, the proximal and distal TG lateralization (pTGL and dTGL, respectively) ratios, and the TT lateralization (TTL) ratio. Other measures of interest included the lateral trochlear inclination angle, sulcus angle, and lateral patellar inclination angle. Univariate regression was used to determine the associations of TD (lateral trochlear inclination angle, sulcus angle) with rTER and the TG position, and multivariate regression was used to model associations among all the variables with the proximal and distal TT-TG distances. RESULTS: rTER was significantly higher in the study group (P < .001), and univariate regression showed a significant association between dysplasia measures and rTER (P < .001). The pTGL ratio was lower in the study group (P = .025), but there was no difference in the dTGL ratio (P = .090) or the TTL ratio (P = .098) between the groups. There were no associations between dysplasia measures and the pTGL and dTGL ratios (P > .05). Multivariate regression showed that the proximal TT-TG distance is predicted by the sulcus angle, pTGL ratio, rTER, and TTL ratio (P < .05) and that the distal TT-TG distance is predicted by the lateral patellar inclination angle, dTGL ratio, sulcus angle, rTER, and TTL ratio (P < .05). CONCLUSION: rTER had a significant association with TD. The position of the proximal TG was more medial in patients with PI. There was no significant difference in the TTL ratio between patients with and without PI. The TT-TG distance was associated with multiple anatomic measures and was not solely predicated on the position of the TT.

Reliability of Radiographic Imaging Characteristics for Osteochondritis Dissecans of the Capitellum.

BACKGROUND: A primary challenge in the treatment of capitellar osteochondritis dissecans (OCD) is accurate imaging assessment. Radiographic classification consensus is not available in the current literature, and correlation of radiographs with lesion stability and resultant best treatment is lacking. PURPOSE: To determine the inter- and intrarater reliability of the presence or absence and common radiographic characteristics of capitellar OCD lesions. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 3. METHODS: Anteroposterior, lateral, and oblique radiographs for 29 cases were reviewed by 7 orthopaedic surgeons. Images were assessed for elbow anthropometry and morphology, OCD presence, lesion characteristics, the presence of progeny bone and progeny features, and radial head abnormalities. Intra- and interrater reliability was assessed using Fleiss and Cohen kappa for nominal variables and intraclass correlation coefficients (ICCs) for continuous variables. RESULTS: Surgeons demonstrated substantial to excellent inter- and intrarater reliability when assessing elbow characteristics: anthropometric (interrater ICC, 0.94-0.99; intrarater ICC, 0.82-0.96) and morphologic (Fleiss, 0.61-0.76; Cohen, 0.68). When the OCD lesion was assessed, fair to moderate interrater agreement was found for classifying the absence or presence of a lesion (Fleiss, 0.28-0.46) and the location of the OCD (Fleiss, 0.24-0.52), poor agreement for assessing the contour of the lesion (Fleiss, 0.00-0.09), and excellent agreement for measuring the size of the lesion (ICC, 0.82-0.94). Poor to fair interrater agreement was found for radial head abnormalities (Fleiss, 0.00-0.27). Progeny bone visualization and fragmentation demonstrated moderate interrater agreement (Fleiss, 0.43-0.47) where displacement of the bone demonstrated poor interrater agreement (Fleiss, 0.11-0.16). Intrarater agreement for OCD lesion characteristics, progeny bone visualization, and progeny bone features was moderate to excellent. CONCLUSION: Given only the fair to moderate agreement among raters for identifying OCD on radiographs, this imaging modality may not serve as a dependable screening tool in isolation. Additional imaging should be obtained if the clinical presentation suggests capitellar OCD and a definitive diagnosis is not possible with radiographs. However, clinicians can reliability measure the size of radiographically apparent OCD, suggesting that radiographs may serve as an appropriate imaging modality for follow-up care.

All-Inside Meniscus Repair.

PURPOSE OF REVIEW: The indications for partial meniscectomy are becoming increasingly limited, and recent evidence suggests that the meniscus should be preserved whenever possible. Because of its many proposed advantages, all-inside meniscus repairs are becoming increasingly common. This review discusses the indications, advantages, disadvantages, and biomechanical and clinical outcomes of all-inside meniscus repair. RECENT FINDINGS: All-inside meniscus repair demonstrates equal functional outcomes, healing rates, and complications compared to inside-out repair of vertical longitudinal and bucket-handle tears with the advantages of decreased surgical time and faster post-operative recovery. In addition, return-to-sport and activity levels are high following all-inside repair regardless of whether concomitant anterior cruciate ligament reconstruction is performed. Biomechanical studies have demonstrated advantages of all-inside meniscal based repairs on radial and horizontal tears. All-inside meniscus repair compares favorably to inside-out repair of vertical longitudinal and bucket-handle tears and continues to increase in popularity. Both capsular based and meniscal based repairs can be used to repair a variety of tear patterns. While biomechanical results are encouraging, further research on the clinical outcomes of meniscal based repairs is needed to elucidate the role of these techniques in the future.

Patellar Height Correlates Modestly With Trochlear Dysplasia: A Magnetic Resonance Imaging Analysis.

Purpose: To evaluate whether there is a correlation between the position of the patella and trochlear morphology in patients with and without patellar instability using exclusively MRI measurements. Methods: MRI scans of knees in patients with patellofemoral instability and knees of patients with an ACL (anterior cruciate ligament) tear as a control group were reviewed. Measurements of patellar position (Canton-Deschamps ratio, Patellar Trochlear Index, and lateral patellar inclination) and trochlear morphology (lateral trochlear inclination and sulcus angle) were obtained from each scan. Bivariate and multivariate analysis was performed to identify correlations between study group, demographics, and patellofemoral joint measurements. Results: There were 70 knees in the patellofemoral instability group and 60 knees in the control group. Bivariate analysis showed a significant difference in all measurements between the patellar instability group and the control group. Multivariate analysis showed modest correlations between patellar position and trochlear morphology. The Caton-Deschamps (CD) ratio correlated with patellar trochlear index (P < .001) and lateral trochlear inclination (P < .001). The respective R-square goodness of fit was 41.1%. Patellar trochlear index correlated with CD ratio (P < .001), lateral trochlear inclination (P < .001), lateral patellar inclination (P < .001), and patellar instability group (P = .011). The R-sq goodness of fit was 37.3%. Lateral patellar inclination correlated with patellar trochlear index (P < .001), Lateral trochlear inclination (P < .001), and age at first dislocation or injury (P = .02). The R-sq goodness of fit was 68.56%. Conclusions: Using MRI-based measurements of the patellofemoral joint, we identified modest, but significant, correlations between measures of patellar height (patellar trochlear index, CD ratio, and lateral patellar inclination) and trochlear dysplasia. This correlation is unclear and is likely multifactorial, but on the basis of this work, a causal relationship between trochlear dysplasia and patella alta cannot be established. Clinical Relevance: Radiographic evaluation of the patella and how it relates to the surrounding boney anatomy provides important information regarding our understanding of patella instability and its treatment.

Side Effects and Patient Tolerance with the Use of Blood Flow Restriction Training after ACL Reconstruction in Adolescents: A Pilot Study.

Background: Blood flow restriction training (BFRT) has gained popularity in rehabilitation due to its benefits in reducing muscle atrophy and mitigating strength deficits following anterior cruciate ligament reconstruction (ACLR). While the effectiveness and safety of BFRT has been well studied in healthy adult subjects, there is limited information about the use of BFRT in the adolescent population, specifically related to patient tolerance and reported side effects post ACLR. Purpose: To investigate and record reported side effects and patient tolerance to BFRT during ACLR rehabilitation in adolescents. Study Design: Prospective Cohort Study. Methods: Patients between 12 and 18 years of age who underwent ACLR at Connecticut Children's were included. Patients utilized an automatic personalized tourniquet system and followed a standardized BFRT exercise protocol over 12 weeks starting 8.72 ± 3.32 days post-op. Upon completion of exercise while using BFRT, patients reported side effects and any adverse events were logged. Descriptive statistics were used to describe the reported side effects and adverse events associated with BFRT and calculate the frequencies of those events over a 12-week period. Results: Five hundred and thirty-five total BFRT sessions were completed between 29 patients (15.39 ± 1.61 years of age). There were zero reports of subcutaneous hemorrhage (SubQ hemorrhage) and deep vein thrombosis (DVT). Reported minor side effects to BFRT included itchiness of the occluded limb (7.85%), lower extremity paresthesia (2.81%), and dizziness (0.75%). A total of 10.47% of BFR treatment sessions were unable to be completed due to tolerance, and 3.5% of sessions required a reduction in limb occlusion pressure (LOP). Conclusion: These preliminary data suggest that BFRT is safe with only minor side effects noted in the adolescent population after ACLR. Further investigations are warranted to continue to evaluate patient tolerance and safety with BFRT, because while these preliminary results suggest a positive safety profile and good tolerance in the adolescent population after ACLR, they represent the experiences of only a small sample. Level of Evidence: Level 3.

Reliability of a New Arthroscopic Discoid Lateral Meniscus Classification System: A Multicenter Video Analysis.

BACKGROUND: The discoid lateral meniscus (DLM) is one of the most common congenital anomalies of the knee. The pathomorphology of DLM varies. Current classification systems are inadequate to describe the spectrum of abnormality. PURPOSE: A study group of pediatric orthopaedic surgeons from 20 academic North American institutions developed and tested the reliability of a new DLM classification system. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: After reviewing existing classifications, we developed a comprehensive DLM classification system. Four DLM features were evaluated: meniscal width, meniscal height, peripheral stability, and meniscal tear. Stepwise arthroscopic examination using anteromedial and anterolateral viewing portals was established for evaluating these features. Three senior authors who were not observers selected 50 of 119 submitted videos with the best clarity and stepwise examination for reading. Five observers performed assessments using the new classification system to assess interobserver reliability, and a second reading was performed by 3 of the 5 observers to assess intraobserver reliability using the Fleiss κ coefficient (fair, 0.21-0.40; moderate, 0.41-0.60; substantial, 0.61-0.80; excellent, 0.81-1.00). RESULTS: Interobserver reliability was substantial for most rating factors: meniscal width, meniscal height, peripheral stability, tear presence, and tear type. Interobserver reliability was moderate for tear location. Intraobserver reliability was substantial for meniscal width and meniscal height and excellent for peripheral stability. Intraobserver agreement was moderate for tear presence, type, and location. CONCLUSION: This new arthroscopic DLM classification system demonstrated moderate to substantial agreement in most diagnostic categories analyzed.

Patellar Tendon Imbrication for Patella Alta.

Patella alta is a significant contributor to patellar instability. Historically, distalizing tibial tubercle osteotomy has been recommended for this problem; however, complications such as nonunion, fracture and hardware irritation are concerning. Additionally, the procedure cannot be performed on skeletally immature patients without violation of the proximal tibial physis. The authors describe a technique of patellar tendon imbrication that does not involve hardware or osteotomy. This technique allows for reliable correction of patella alta and provides patellar stability without the complications associated with osteotomy.

Anterior cruciate ligament (ACL) repair using cortical or anchor fixation with suture tape augmentation vs ACL reconstruction: A comparative biomechanical analysis.

BACKGROUND: The purpose was to compare knee kinematics in a cadaveric model of anterior cruciate ligament (ACL) repair using an adjustable-loop femoral cortical suspensory (AL-CSF) or independent bundle suture anchor fixation (IB-SAF) with suture tape augmentation to a bone-patellar tendon-bone (BPTB) ACL reconstruction. METHODS: Twenty-seven cadaveric knees were randomly assigned to one of three surgical techniques: (1) ACL repair using the AL-CSF technique with suture tape augmentation, (2) ACL repair using the IB-SAF technique with suture tape augmentation, (3) ACL reconstruction using a BPTB autograft. Each specimen underwent three conditions according to the state of the ACL (native, proximal transection, repair/reconstruction) with each condition tested at four different angles of knee flexion (0°, 30°, 60°, 90°). Anterior tibial translation (ATT) and internal tibial rotation (ITR) were evaluated using 3-dimensional motion tracking software. RESULTS: ACL transection resulted in a significant increase in ATT and ITR when compared to the native state (P < 0.001, respectively). ACL repair with the AL-CSF or IB-SAF technique as well as BPTB reconstruction restored native ATT and ITR at all tested angles of knee flexion, while showing significantly less ATT at 0°, 30°, 60°, and 90° as well as significantly less ITR at 30°, 60°, and 90° of knee flexion when compared to the ACL-deficient state. There were no significant differences in ATT and ITR between the three techniques utilized. CONCLUSION: ACL repair using the AL-CSF or IB-SAF technique with suture tape augmentation as well as BPTB ACL reconstruction each restored native anteroposterior and rotational laxity, without significant differences in knee kinematics between the three techniques utilized. LEVEL OF EVIDENCE: Controlled Laboratory Study.

Short-term isokinetic and isometric strength outcomes after anterior cruciate ligament reconstruction in adolescents.

OBJECTIVES: To examine differences in knee strength outcomes after ACL reconstruction according to quadriceps tendon (QT) or hamstring tendon (HT) autograft in adolescents. DESIGN: Retrospective cohort. METHODS: Surgical and clinical outcome data were collected. Analyses were conducted separately for female and male cohorts and grouped by graft type (HT or QT). A Mann-Whitney U test of independent samples was used to examine group differences according to graft type. RESULTS: 107 females (age = 15.6 ± 1.5 years) and 94 males (age = 15.7 ± 1.5 years) were included. Mean time since surgery ranged from 7.2 to 7.9 months. Those with a QT autograft had decreased normalized isokinetic quadriceps peak torque on the involved limb compared to the HT group (p < 0.01, ES = 0.71-0.89). Normalized isometric hamstring peak torque was decreased for those with HT autograft in the female cohort (p = 0.02, ES = 0.57). CONCLUSION: Normalized isokinetic quadriceps peak torque was reduced by 18-20% on the involved limb in those with a QT autograft. Normalized isometric hamstring peak torque was decreased by 13% for those with HT autograft in the female cohort. Method of strength testing may be an important consideration to fully appreciate strength deficits after ACL reconstruction according to graft type.

Descriptive Epidemiology From the Research in Osteochondritis Dissecans of the Knee (ROCK) Prospective Cohort.

BACKGROUND: Osteochondritis dissecans (OCD) occurs most commonly in the knees of young individuals. This condition is known to cause pain and discomfort in the knee and can lead to disability and early knee osteoarthritis. The cause is not well understood, and treatment plans are not well delineated. The Research in Osteochondritis Dissecans of the Knee (ROCK) group established a multicenter, prospective cohort to better understand this disease. PURPOSE: To provide a baseline report of the ROCK multicenter prospective cohort and present a descriptive analysis of baseline data for patient characteristics, lesion characteristics, and clinical findings of the first 1000 cases enrolled into the prospective cohort. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients were recruited from centers throughout the United States. Baseline data were obtained for patient characteristics, sports participation, patient-reported measures of functional capabilities and limitations, physical examination, diagnostic imaging results, and initial treatment plan. Descriptive statistics were completed for all outcomes of interest. RESULTS: As of November 2020, a total of 27 orthopaedic surgeons from 17 institutions had enrolled 1004 knees with OCD, representing 903 patients (68.9% males; median age, 13.1 years; range, 6.3-25.4 years), into the prospective cohort. Lesions were located on the medial femoral condyle (66.2%), lateral femoral condyle (18.1%), trochlea (9.5%), patella (6.0%), and tibial plateau (0.2%). Most cases involved multisport athletes (68.1%), with the most common primary sport being basketball for males (27.3% of cases) and soccer for females (27.6% of cases). The median Pediatric International Knee Documentation Committee (Pedi-IKCD) score was 59.9 (IQR, 45.6-73.9), and the median Pediatric Functional Activity Brief Scale (Pedi-FABS) score was 21.0 (IQR, 5.0-28.0). Initial treatments were surgical intervention (55.4%) and activity restriction (44.0%). When surgery was performed, surgeons deemed the lesion to be stable at intraoperative assessment in 48.1% of cases. CONCLUSION: The multicenter ROCK group has been able to enroll the largest knee OCD cohort to date. This information is being used to further understand the pathology of OCD, including its cause, associated comorbidities, and initial presentation and symptoms. The cohort having been established is now being followed longitudinally to better define and elucidate the best treatment algorithms based on these presenting signs and symptoms.

Discoid Lateral Meniscus Saucerization and Treatment of Intrasubstance Degeneration Through an Accessory Medial Portal Using a Small Arthroscope.

Discoid lateral meniscus (DLM) is a rare meniscal variant characterized by an increased amount of meniscal tissue that resembles the shape of a disc as opposed to the typical crescent shape of the lateral meniscus. Surgical intervention is recommended for symptomatic DLM with persistent pain, mechanical symptoms, or motion impairment. The technique described is a reliable and reproducible method to identify and treat intrasubstance degeneration (ID) in the setting of DLM. A small arthroscope is used that allows more room for a meniscal repair device, as well as improved visualization and access of the lateral compartment. An accessory medial portal is used that allows perpendicular access to the anterior half of the body, as well as the posterior aspect of the anterior horn for repair. Successful surgery with this technique preserves meniscus and produces a strong reliable all-meniscal based repair of ID that allows early weight bearing and range of motion postoperatively.

Effect of Static Alignment on Dynamic Knee Abduction Moments in Adolescent Athletes with Recent ACL Reconstruction.

PURPOSE: Dynamic limb valgus, particularly high knee abduction moments, is a known risk factor for anterior cruciate ligament (ACL) injury and may result from poor static anatomic limb alignment, faulty biomechanics, or a combination of both. The purpose of this study was to assess the influence of static lower extremity anatomic alignment and dynamic kinematic/kinetic measures on knee abduction moments during sidestep cutting in adolescent athletes with recent ACL reconstruction. METHODS: This retrospective study included 50 adolescents with recent unilateral ACL reconstruction (18/50 female, mean age = 15.8 yr, 7.6 months postsurgery). Frontal plane hip-to-ankle imaging was used to measure mechanical axis deviation and tibial-femoral angle. Three-dimensional motion capture provided lower extremity kinematics and kinetics during quiet standing and during the loading phase (initial contact to peak knee flexion) of an anticipated 45° sidestep cut. Imaging, static motion capture, and dynamic motion capture measures were investigated as potential predictors of average dynamic knee abduction moment using correlation and backward stepwise linear regression. RESULTS: Dynamic knee abduction moment was best predicted by a combination of younger age and dynamic measures: trunk lean toward the planting limb, knee abduction and external rotation, and ankle inversion. Although static measures were correlated with dynamic knee abduction moment in univariate analysis, no static/anatomic variables entered the model once the dynamic measures were included. CONCLUSION: Knee abduction moments during sidestep cutting were related to dynamic factors reflecting frontal and transverse plane motion. Static (anatomic) lower limb alignment did not influence knee abduction moments once these dynamic factors were considered. Knee abduction moments and ACL injury risk are therefore not dictated by anatomic alignment and can be altered through neuromuscular/biomechanical training.