Anterior cruciate ligament reconstruction in the over-50s. A prospective comparative study between surgical and functional treatment.

INTRODUCTION: In patients aged over-50 years, although data are sparse, results of anterior cruciate ligament (ACL) surgery are good if selection is correctly performed. However, non-operative treatment is usually proposed for this age group, as patients generally prefer just to scale down their sports activities. Non-operative results are acceptable, but with a high risk of residual instability, secondary lesions and lifestyle alteration. The main aim of the present study was to compare results between surgical versus non-surgical treatment of ACL tear in over-50 year-olds. Secondary objectives comprised assessing prognostic factors for poor functional outcome, and comparing the 2 groups epidemiologically to identify clinical decision-making factors. The study hypothesis was that results are comparable between operative and non-operative treatment of ACL tear. MATERIAL AND METHOD: Three hundred twenty patients were followed up prospectively: 92 non-surgical (NS group) and 288 surgical (S group). Classical epidemiological data were collected. Clinical laxity, differential laximetry, KOOS, IKDC, Tegner and ACL-RSI scores and radiologic assessment were collected pre- and postoperatively, as were intraoperative data. Early and late complications were collected. RESULTS: All patients were followed up. Patients were principally female, and were older, less athletic, with more stable knee and less severe functional impact in the NS group. Functional scores improved in both groups, and especially in group S, where sports scores were also better. In the NS group, laximetry at follow-up correlated with preoperative marked pivot-shift (p=0.024). Severe differential laxity was predictive of poor IKDC score (p=0.06). In the S group, laximetry at follow-up correlated with preoperative explosive pivot-shift (p<0.001), lateral meniscal lesion (p=0.007), use of hamstring tendon (p=0.007), and non-operated early complications (p=0.004). Factors for poor global KOOS score in group S comprised female gender (p<0.001), high BMI (p<0.001) and skiing (p=0.038). Factors for poor Tegner scores comprised skiing or team sport (p<0.05), isolated moderate medial osteoarthritis (p=0.01), and non-operated early complications (p=0.022). Factors for poor IKDC score comprised female gender (p=0.064), and non-operated early complications (p=0.019). Complications did not differ between groups. DISCUSSION/CONCLUSION: Results were satisfactory in both groups, with significant improvement in functional scores, but were better in group S. For NS patients, pivot sport was barely feasible and sports activity scores decreased. In case of severe laxity at diagnosis, surgical treatment should be proposed. LEVEL OF EVIDENCE: III; non-randomized prospective comparative series.

Female gender and medial meniscal lesions are associated with increased pain and symptoms following anterior cruciate ligament reconstruction in patients aged over 50 years.

PURPOSE: Several studies report satisfactory clinical outcomes following ACLR in older patients, but none evaluated the effects of meniscal and cartilage lesions. The aim was to evaluate the influence of meniscal and cartilage lesions on outcomes of ACLR in patients aged over 50 years. METHODS: The authors prospectively collected records of 228 patients that underwent primary ACLR, including demographics, time from injury to surgery, whether injuries were work related, and sports level (competitive, recreational, or none). At a minimum follow-up of 6 months, knee injury and osteoarthritis outcome scores (KOOS), International Knee Documentation Committee (IKDC) score and Tegner activity level were recorded, and differential laxity was measured as the side-to-side difference in anterior tibial translation (ATT) using instrumented laximetry devices. Regression analyses were performed to determine associations between outcomes and meniscal and cartilage lesions as well as nine independent variables. RESULTS: A total of 228 patients aged 54.8 ± 4.3 years at index ACLR were assessed at a follow-up of 14.3 ± 3.8 months. KOOS subcomponents were 85 ± 13 for symptoms, 91 ± 10 for pain, 75 ± 18 for daily activities, 76 ± 18 for sport, and 88 ± 12 for quality of life (QoL). The IKDC score was A for 84 (37%) knees, B for 96 (42%) knees, C for 29 (13%) knees, and D for 8 (4%) knees. Tegner scores showed a decrease (median 0, range -4 to 4) and differential laxity also decreased (median - 4, range - 23.5 to 6.0). KOOS symptoms worsened with higher BMI (p = 0.038), for women (p = 0.007) and for knees that had medial meniscectomy (p = 0.029). KOOS pain worsened with higher BMI (p ≤ 0.001), for women (p = 0.002) and for knees with untreated (p = 0.047) or sutured (p = 0.041) medial meniscal lesions. Differential laxity increased with follow-up (p = 0.024) and in knees with lateral cartilage lesions (p = 0.031). CONCLUSION: In primary ACLR for patients aged over 50 years, female gender and medial meniscal lesions significantly compromised KOOS symptoms and pain, while lateral cartilage lesions significantly increased differential laxity. Compared to knees with an intact medial meniscus, those with sutured or untreated medial meniscal lesions had worse pain, while those in which the medial meniscus was resected had worse symptoms. These findings are clinically relevant as they could help surgeons with patient selection and adjusting expectations according to their functional demands. LEVEL OF EVIDENCE: III.

ACL reconstruction in over-50 year-olds: Comparative study between prospective series of over-50 year-old and under-40 year-old patients.

INTRODUCTION: ACL reconstruction is increasingly proposed for over-50 year-olds, although surgery had a poor reputation in this age-group, mainly due to postoperative stiffness. ACL reconstruction results were compared between two prospective series of, respectively, over-50 year-old (group 1) and under-40 year-old patients (group 2). The main study hypothesis was that ACL surgery provides the same functional results after 50 as before 40 years of age, and the secondary hypothesis was that the rate of complications does not differ. METHODS: A multicenter prospective non-randomized follow-up study included 228 over-50 year-old and 130 under-40 year-old patients in 10 public and private sector centers. Epidemiological data were collected. Clinical laxity, differential laxity, KOOS, IKDC, Tegner and ACL-RSI scores and radiologic aspect were assessed pre- and post-operatively. Early (<3 months) and late (>3 months) complications were collected. Functional scores were compared between groups at last follow-up: 14.2 months (range, 3.5-30.5 months in group 1, and 20.5 months (range, 11.4-29.4 months) in group 2. RESULTS: Analysis of epidemiological data showed some inter-group differences: female predominance in group 1 (59% versus 35%), longer trauma-to-surgery time in group 2 (23.6 versus 8.7 weeks), predominance of pivot-contact (team) sports in group 2 (49% versus 6%), and predominance of pivot sports (skiing) in group 1. Tegner scores were lower in group 1 (5.2 versus 7.6). Meniscal lesions were more frequent in group 1 (68% versus 36%), as were cartilage lesions (76% versus 10%). Initial laxity levels were identical (6.5mm in group 1 and 6.7mm in group 2). Type of surgery was identical: 86% hamstring graft in group 1 and 89% in group 2. There were more early complications (hematoma) in group 1; rates of late complications were comparable. Laxity at last follow-up was 2.2mm in both groups, and thus Lachman and pivot-shift test results were identical in terms of firm end-feel and absence of pivot shift. Quality-of-life assessment found higher KOOS scores in group 2, although ACL-RSI scores were identical. Global IKDC scores were slightly better in group 2, due to osteoarthritis in the older patients. CONCLUSION: ACL reconstruction after 50 years of age gave good results, correcting laxity as effectively as in under-40 year-olds, with identical technique and identical rates of complications. Time to return to sports and resumed level were comparable. LEVEL AND TYPE OF STUDY: III, prospective comparative non-randomized.

Factors affecting outcome of ACL reconstruction in over-50-year-olds.

INTRODUCTION: With increasing life expectancy and ever-improving quality of life in industrialized countries, functional demand and sports levels are increasing in older subjects, who are thus exposed to central pivot lesions almost as much as younger ones. While non-operative treatment provides acceptable results, it entails significant reduction in sports level. The aim of the present study was to analyze medium-term clinical, functional and radiological results of anterior cruciate ligament (ACL) reconstruction in over-50-year-olds, in order to identify factors for failure. HYPOTHESIS: The study hypothesis was that surgical management provides good results if patient selection is rigorous. PATIENTS AND METHODS: A multicenter retrospective study included 398 patients undergoing ACL reconstruction between April 1, 2009 and December 6, 2016. Inclusion criteria comprised: age≥50 years, with proven ACL tear. Preoperatively, clinical work-up was supplemented by measurement of differential anterior laxity and radiologic assessment of cartilage status. Functional level was assessed on the objective IKDC score. Intraoperative data comprised type of graft and meniscal and cartilage status. The same parameters were assessed postoperatively. Functional results were assessed on objective IKDS, KOOS and ACL-RSI scores. RESULTS: The mean follow-up was 42.2 months. The mean improvement in differential anterior laxity was 4.2mm. Pivot-shift showed improvement, with 97% absent or glide (p<0.001). Objective IKDC score showed significant improvement (p<0.0001). 23% of patients had poor clinical results: IKDC C or D. Preoperative explosive pivot-shift (p<0.0001), medial tibiofemoral osteoarthritis (p<0.0001) and medial meniscus lesion (p<0.002) emerged as risk factors for poor functional outcome. CONCLUSION: ACL reconstruction in over-50-year-olds provided satisfactory clinical and functional results. Rigorous patient selection is mandatory, as radiologic signs of medial tibiofemoral osteoarthritis indicate a risk of poor outcome. Surgery may be proposed in patients with high functional and athletic demand, before medial meniscal lesions can set in. In case of explosive pivot shift, associated anterolateral reconstruction should be considered.

Influence of operative technique on anterior cruciate ligament reconstruction in patients older than 50 years.

BACKGROUND: A consequence of the steady growth in the worldwide population of elderly individuals who remain in good health and continue to engage in sports is an increase in the incidence of anterior cruciate ligament (ACL) rupture occurring after 50 years of age. ACL reconstruction was formerly reserved for young athletes but now seems to produce good outcomes in over 50s. The type of graft and graft fixation method were selected empirically until now, given the absence of investigations into potential relationships of these two parameters with the outcomes. The objective of this study was to assess associations linking the type of graft and the method of femoral graft fixation to outcomes in patients older than 50 years at ACL reconstruction. HYPOTHESIS: The operative technique is not associated with the clinical outcomes or differential laxity. MATERIAL AND METHODS: A multicentre retrospective cohort of 398 patients operated between 1 January 2011 and 31 December 2015 and a multicentre prospective cohort of 228 patients operated between 1 January 2016 and 30 June 2017 were conducted. Mean follow-up was 42.7 months in the retrospective cohort and 14.2 months in the prospective cohort. The primary evaluation criterion was the clinical outcome as assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Tegner Activity Score (TAS). Differential laxity was the secondary evaluation criterion. The Wilcoxon rank sum test and Kruskal-Wallis test were used to compare groups, and p-values<0.05 were considered significant. RESULTS: In the retrospective and prospective cohorts, hamstring tendons were used in 269 (67.6%) and 197 (86.4%) patients and extensor apparatus tendons in 124 (31.2%) and 31 (13.6%) patients. Femoral fixation in the retrospective cohort was cortical in 81 (20.4%) cases, by press-fit in 112 (28.1%) cases, and by interference screw in 205 (51.5%) cases; corresponding figures in the prospective cohort were 135 (59.2%), 17 (7.5%), and 76 (33.3%). The multivariate analysis of the retrospective data identified no significant associations of graft type or femoral fixation type with the KOOS, TAS, or differential laxity values. In the prospective cohort, hamstring grafts were associated with 0.6mm of additional laxity (p=0.007); compared to cortical fixation, press-fit fixation of patellar tendon grafts was associated with 0.3mm of additional laxity (p=0.029) and a 0.5-point lower TAS value (p=0.033), with no difference in KOOS values. None of these differences were clinically significant. DISCUSSION: The various ACL reconstruction techniques used in patients older than 50 years produce similar outcomes. The technique can be chosen based on surgeon preference without regard for patient age. LEVEL OF EVIDENCE: IV.

Anterior Laxity at 2 Years After Anterior Cruciate Ligament Reconstruction Is Comparable When Using Adjustable-Loop Suspensory Fixation and Interference Screw Fixation.

BACKGROUND: Adjustable-loop suspensory fixation (ALSF) devices are commonly used in anterior cruciate ligament reconstruction (ACLR). However, concern exists regarding the potential for lengthening under cyclical loads. PURPOSE: To compare the residual anterior laxity of 2 methods of femoral fixation, ALSF versus interference screw fixation, in patients undergoing isolated ACLR in the absence of meniscal injuries. To determine the preoperative risk factors associated with residual postoperative anterior laxity. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A retrospective analysis was performed comparing 2 groups of patients that underwent primary ACLR using ALSF versus bioabsorbable interference screw fixation. Anterior knee laxity was assessed with Telos stress radiography, while functional outcomes were evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS) and Tegner activity level scale at a minimum of 2 years postoperatively. A multivariate analysis was performed to identify factors associated with residual postoperative laxity >3 mm. RESULTS: Of the 1136 patients who underwent ACLR during the study period, 363 met the inclusion criteria. A total of 272 patients (75%) (mean age, 31.7 ± 10.7 years) with a mean follow-up of 25.7 ± 4.6 months (range, 24-36 months) consented to participate (screw group: n = 121; ALSF group: n = 151). The 2 groups were statistically comparable in terms of age, sex ratio, time from injury to surgery, graft diameter, preoperative laxity, preoperative objective International Knee Documentation Committee (IKDC) grade, and preoperative Tegner score. The mean postoperative laxity as a continuous variable was significantly different comparing the ALSF and screw groups (1.49 ± 1.98 mm and 2.32 ± 1.97 mm, respectively; P < .001). In the screw group, 76 patients (62.8%) had normal (<3 mm), 40 (33.1%) had nearly normal (3-6 mm), and 5 (4.1%) had abnormal (≥6 mm) postoperative knee laxity according to the IKDC grade, while in the ALSF group, 112 patients (74.2%) had normal, 37 (24.5%) had nearly normal, and 2 (1.3%) had abnormal laxity ( P = .0833). No significant difference was found in KOOS or Tegner scores comparing the 2 femoral fixation methods: KOOS, 90.6 ± 7.5 (ALSF group) and 90.6 ± 7.4 (screw group) ( P = .7631), versus Tegner, 6.5 ± 1.3 (ALSF group) and 6.3 ± 1.4 (screw group) ( P = .2992). A negative correlation was found between postoperative laxity and final Tegner ( rs = -0.303, P < .001) and KOOS scores ( rs = -0.168, P = .005). The initial univariate analysis showed differences between groups of patients with residual knee laxity ≥3 mm and <3 mm on preoperative pivot shift, preoperative laxity, age, fixation type, and preoperative objective IKDC grade. The multivariate analysis on these factors showed that the pivot shift remained the only significant predictor for residual laxity ≥3 mm for pivot shift grade 2 compared with grade 1 (odds ratio, 4.689 [95% CI, 2.465-9.286]) and for pivot shift grade 3 compared with grade 1 (odds ratio, 58.025 [95% CI, 12.757-557.741]) ( P < .001). CONCLUSION: For primary ACLR, the use of an ALSF device for femoral fixation is associated with noninferior postoperative anterior knee laxity results compared with interference screw fixation at a minimum 2 years' follow-up. The preoperative pivot shift is the only significant risk factor for postoperative residual anterior knee laxity >3 mm.

The lateralization and distalization shoulder angles are important determinants of clinical outcomes in reverse shoulder arthroplasty.

BACKGROUND: Reverse shoulder arthroplasty (RSA) designs vary in the lateralization and distalization geometry, which may affect functional outcomes. The purpose was to determine the effect of RSA lateralization and distalization on final functional outcomes by using the "lateralization shoulder angle" (LSA) and the "distalization shoulder angle" (DSA). METHODS: Forty-six consecutive patients who underwent RSA for cuff tear arthropathy were retrospectively evaluated. Functional outcome and radiographs were evaluated at a minimum of 2 years postoperatively and compared between implants with or without glenoid lateralization and with or without humeral-sided lateralization. Anteroposterior shoulder radiographs were used to evaluate the LSA and DSA. RESULTS: Both angles showed substantial to almost perfect intrarater and inter-rater agreement. Higher LSA values were found in more lateralized RSAs (P = .027), and values between 75° and 95° were correlated with better active external rotation (quadratic regression analysis R2 = 0.553, P < .001). Postoperative active anterior elevation (R2 = 0.2, P = .008), Constant (rs = 0.29, P = .05), and Activities of Daily Living Requiring External Rotation scores (rs = 0.4 P = .007) had a positive correlation with the LSA. The quadratic regression analysis also showed that a DSA between 40° and 65° resulted in better active anterior elevation (R2 = 0.4, P < .001) and abduction (R2 = 0.4, P < .001). The negative correlation between the LSA and DSA (rs = -0.7, P < .001) revealed that, according to the implant used, the more distally the RSA is placed the less lateralization is achieved. CONCLUSIONS: The LSA and the DSA are reproducible measurements that may be used to estimate "lateralization and distalization" after RSA. These measurements are correlated with postoperative clinical outcomes.

Factors that influence blood loss and need for transfusion following total knee arthroplasty.

BACKGROUND: Blood loss during total knee arthroplasty (TKA) remains a concern, as many patients require blood transfusions, which increase risks of allergic reactions, disease transmission, and thromboembolisms. The purpose was to determine factors associated with blood loss and need for transfusion in patients receiving routine TKA. METHODS: The authors prospectively analyzed 150 consecutive uncemented TKAs for age, gender, body mass index (BMI), anticoagulant medication, type of anesthesia, tranexamic acid (TXA) administration, tourniquet inflation, drain placement, pre- and post-operative Haemoglobin (Hb) level (g/dL), and whether transfusion was necessary. Univariable and multivariable regression analyses were performed to identify factors associated with Hb loss and need for transfusion with significance level set at P value<0.05. RESULTS: The cohort comprised 92 women and 58 men, aged 69.5±8.9 years. The mean Hb loss was 3.7±1.3 g/dL. The 20 patients (13%) who had transfusions also had lower preoperative Hb (12.6±1.2 g/dL) compared to the remaining patients (14.3±1.2 g/dL). Hb loss was significantly associated with preoperative Hb, TXA, and gender, but multivariable regression identified gender as a confounder and indicated that TXA reduced Hb loss by 0.92 g/dL. Multivariable regression revealed the need for transfusion was only significantly associated with preoperative Hb and indicated that a decrease of preoperative Hb by 1 g/dL nearly quadrupled the chances of needing transfusion. CONCLUSIONS: Hb loss was significantly associated with preoperative Hb levels and use of TXA, while the need for transfusion was only associated with preoperative Hb levels. These findings could help identify patients at risk for blood transfusions. Level of evidence: level III, prospective case series.

Adjustable Button Devices for All-Arthroscopic Posterior Cruciate Ligament Reconstruction Using the Hamstrings Tendons and the "Forgotten" Transseptal Approach.

Posterior cruciate ligament (PCL) ruptures account for nearly 20% of all ligamentous knee injuries. These may be either isolated or in the setting of a more complex knee trauma. Isolated tears with moderate posterior laxity (grades I or II) are commonly treated conservatively; nevertheless, symptomatic grade III injuries frequently require surgical intervention. PCL reconstruction remains a challenging surgery for multiple reasons like the neurovascular structures' proximity, the difficult passage of the graft with the "killer turn" angle, or the risk of poor graft fixation. We describe an all-inside operative technique using hamstrings tendon autografts with tibial and femoral adjustable buttons cortical fixation and the visualization of the posterior transseptal portal.

All-Arthroscopic Suture Fixation of Patellar Osteochondritis Dissecans.

Osteochondritis dissecans of the knee, despite its cause, is characterized by the impairment of the subchondral bone. Failure of its spontaneous healing makes surgical fixation often necessary. The patella is less affected than other locations in the knee. Its surgical treatment remains a challenge due to the thickness of the lesion and the complex approach of the retropatellar cartilage. Arthroscopy has the theoretical advantage to avoid a possible arthrotomy; however, the retrograde application of fixation materials does not guarantee good fragment compression and may lead to cartilage penetration and damage. The purpose of this Technical Note is to present a reproducible, full arthroscopic suture fixation technique for patellar osteochondritis dissecans lesions. By using the posterior cruciate tibial drill guide, absorbable sutures are passed through the center and the peripheral borders of the lesion resulting in a "spider-parachute-type" fixation with direct fragment compression.

Minimally Invasive Combined Anterior and Anterolateral Stabilization of the Knee Using Hamstring Tendons and Adjustable-Loop Suspensory Fixation Device: Surgical Technique.

Despite the numerous techniques described regarding isolated anterior cruciate ligament (ACL) reconstruction, many authors have reported that residual knee rotational instability is not always eliminated. The combination of lateral extra-articular knee tenodesis and ACL reconstruction is an alternative surgical approach with very promising clinical results. The purpose of this article is to describe a reliable and reproducible technique of combined ACL reconstruction and lateral extra-articular knee tenodesis using a continuous looped hamstring tendon autograft. A 4-strand graft inside the joint and a 2-strand graft for the tenodesis are attached to 2 adjustable-loop button suspensory fixation devices.

Is the two-dimensional computed tomography scan analysis reliable for coracoid graft positioning in Latarjet procedures?

BACKGROUND: The aim of the study was to develop a computed tomography (CT)-based measurement protocol for coracoid graft (CG) placement in both axial and sagittal planes after a Latarjet procedure and to test its intraobserver and interobserver reliability. METHODS: Fifteen postoperative CT scans were included to assess the intraobserver and interobserver reproducibility of a standardized protocol among 3 senior and 3 junior shoulder surgeons. The evaluation sequence included CG positioning, its contact area with the glenoid, and the angle of its screws in the axial plane. The percentage of CG positioned under the glenoid equator was also analyzed in the sagittal plane. The intraobserver and interobserver agreement was measured by the intraclass correlation coefficient (ICC), and the values were interpreted according to the Landis and Koch classification. RESULTS: The ICC was substantial to almost perfect for intraobserver agreement and fair to almost perfect for interobserver agreement in measuring the angle of screws in the axial plane. The intraobserver agreement was slight to almost perfect and the interobserver agreement slight to substantial regarding CG positioning in the same plane. The intraobserver agreement and interobserver agreement were both fair to almost perfect concerning the contact area. The ICC was moderate to almost perfect for intraobserver agreement and slight to almost perfect for interobserver agreement in analyzing the percentage of CG under the glenoid equator. CONCLUSION: The variability of ICC values observed implies that caution should be taken in interpreting results regarding the CG position on 2-dimensional CT scans. This discrepancy is mainly explained by the difficulty in orienting the glenoid in the sagittal plane before any other parameter is measured.

Histological features of the ACL remnant in partial tears.

BACKGROUND: The aim of this study was to investigate the histological features of the remaining fibers bridging the femur and tibia in partial ACL tears. METHODS: Twenty-six ACL remnants were harvested from patients who had arthroscopic criteria concordant with a partial tear. Histological analysis includes cellularity, blood vessel density evaluation and characterization of the femoral bony insertion morphology. Immunohistochemical studies were carried out to determine cells positive for α-smooth actin and for mechanoreceptor detection. RESULTS: In these samples, a normal femoral insertion of the remnant was present in 22.7% of the cases. In 54% of the samples, substantial areas of hypercellularity were observed. Myofibroblasts were the predominant cell type and numerous cells positive for α-smooth actin were detected at immunostaining. Blood vessel density was increased in hypercellularity areas and in the synovial sheet. Free nerve endings and few Golgi or Ruffini corpuscles were detected in 41% of the specimens. The cellularity was correlated to the time between injury to surgery (p=0.001). CONCLUSION: Competent histological structures including a well-vascularized synovial sheet, numerous fibroblasts and myofibroblasts and mechanoreceptors were found in ACL remnants. These histological findings bring additional knowledge towards the preservation of the ACL remnant in partial tears when ACL reconstruction or augmentation is considered. CLINICAL RELEVANCE: Descriptive laboratory study.

The diagnostic value of clinical tests, magnetic resonance imaging, and instrumented laxity in the differentiation of complete versus partial anterior cruciate ligament tears.

PURPOSE: To evaluate the question of whether different arthroscopically confirmed anterior cruciate ligament (ACL) injury patterns have distinctive preoperative findings on clinical examination, instrumented laxity, and magnetic resonance imaging (MRI). METHODS: Three hundred consecutive ACL-deficient patients with isolated ACL tears were evaluated with the Lachman test (LT), the pivot-shift test (PST), stress radiographs using the Telos Stress Device (Metax, Hungen, Germany), and MRI. After arthroscopic confirmation of the ACL injury, we grouped patients into 4 different ACL tear types (complete, partial anteromedial [AM] bundle intact, posterolateral [PL] bundle intact, and posterior cruciate ligament [PCL] healing), and partial tears were further evaluated for mechanical integrity and functionality of the remaining fibers. RESULTS: PST grades of +2 and +3 were consistent with complete ACL tears (86%; P < .00001), whereas PST grades of 0 or +1 were strongly related to partial tears (76%; P < .00001). Instrumented laxity results showed a significant difference in side-to-side difference (SSD) of anterior tibial translation in complete tears (9.1 ± 3.4 mm) versus partial tears (5.2 ± 2.9 mm; P < .0001). Most PL-intact cases were "functional" (67%), with lower instrumented laxity values (SSD, 4.3 ± 2.3 mm) than the "nonfunctional" cases (SSD, 6.7 ± 2.9 mm; P < .001). The contrary was not observed for AM-intact cases (17% functional). Partial ACL tears with functional remaining fibers had PST grades of 0 or +1 and less than a 4 mm SSD in stress radiographs (sensitivity, 0.76; specificity, 0.90). Partial ACL tears with nonfunctional fibers had positive PST results and an SSD of anterior tibial displacement from 4 to 9 mm (sensitivity, 0.56; specificity, 0.92). Positive PST results and an SSD greater than 9 mm was recorded in complete ACL tears (sensitivity, 0.88; specificity, 0.96). MRI analysis revealed overlapping results between complete and partial tears. CONCLUSIONS: Preoperative evaluation of different ACL tear types showed differences between complete and partial ACL tears with functional fibers in clinical examination and instrumented laxity tests. The combination of clinical tests and stress radiographs produced threshold values that distinguished complete from partial ACL tears, which may help the surgeon in the early identification of the presence of remaining functional fibers. LEVEL OF EVIDENCE: Level III, case-control study.

Navigated anterior cruciate ligament reconstruction: correlation between computer data and radiographic measurements.

The goal of this study was to prove the reliability of computer-aided navigation for the surgical reconstruction of the anterior cruciate ligament (ACL) using an arthroscopic procedure. The study involved 50 patients preceded by a learning curve period. Computer-recorded data were compared with specific radiography measurements of the frontal and anteroposterior views. The radiographs were used to measure the position of the tibial tunnel in the frontal and sagittal plane, the angulation of the tibial tunnel in the frontal and sagittal plane, and the position of the femoral tunnel in the lateral condyle.