Meniscal Circumferential Fiber Augmentation: A Biomechanical Arthroscopic Meniscal Repair Technique.

Radial tears of the human knee meniscus result in the loss of circumferential hoop stress and are highly correlated with knee degeneration. Although a variety of surgical techniques are available to repair radial meniscal tears, including inside-out, outside-in, and all-inside techniques, conventional repair techniques focus only on stabilizing the damaged portion. This Technical Note describes a biomechanical meniscus repair technique of meniscal circumferential fiber augmentation, concomitant with conventional repair, to promote meniscal healing from a biomechanical perspective.

The Wound Dressing Influenced Effectiveness of Cryotherapy After Anterior Cruciate Ligament Reconstruction: Case-Control Study Comparing Gauze Versus Film Dressing.

Purpose: To compare the clinical effectiveness of cryotherapy after anterior cruciate ligament reconstruction using 2 different wound dressings, conventional postoperative gauze dressings and polyurethane semipermeable transparent film dressings. Methods: In total, 60 patients who had undergone arthroscopic anterior cruciate ligament reconstruction with an autogenous patellar tendon were assigned to 2 groups. The surgical wound was covered with 5 sheets of gauze with an elastic bandage (control group) in 30 patients and film dressing was used (film group) in the remaining 30 patients. Silicone drainage catheters were inserted at the intercondylar notch, beside the distal outlet of the tibial tunnel for 2 days. After 1 hour of cooling using the device, the knee was chilled with an ice bag every 2 hours until the next morning. The severity of pain was evaluated by the number of times an analgesic, 50 mg of diclofenac sodium suppositories, had to be administered in the 24 hours after surgery. The amount of drainage during the following 2 days, the range of motion at 21 days, the change of hemoglobin concentration at 1 and 7 days, and C-reactive protein (CRP) at 1 and 7 days were examined. Results: The number of patients who used an analgesic was 18 in the control group and 7 in the film group (P = .003). The amount of drainage was 165.2 ± 72.9 mL in the control group and 289.7 ± 77.6 mL in the film group (P < .001). The postoperative CRP value was 0.77 ± 0.65 mg/dL at 1 day in the control group and 0.39 ± 0.42 mg/dL in the film group (P = .009). No statistical difference was seen for hemoglobin concentration at 1 or 7 days, CRP at 7 days or range of motion at 21 days. Conclusions: In this study, we found that film dressing enhanced the effect of cryotherapy with respect to pain control, wound drainage, and inflammation immediately after surgery compared with traditional gauze dressing with elastic wrap. Level of Evidence: III, case-control study.

Anatomical rectangular tunnel anterior cruciate ligament reconstruction provides excellent clinical outcomes.

PURPOSE: The purpose of this study was to prospectively evaluate the clinical outcomes following anatomical rectangular tunnel anterior cruciate ligament (ACL) reconstruction with a bone-patellar tendon-bone (BTB) graft using an adjustable-length femoral cortical fixation device with enough patients and a high follow-up rate. METHODS: This study included 125 patients who underwent anatomical rectangular tunnel ACL reconstruction with a BTB graft. A BTB TightRope® was used for femoral graft fixation. Clinical evaluations were performed more than 2 years after surgery using the International Knee Documentation Committee (IKDC) Form. Patients interviewed by telephone were only subjectively evaluated. The side-to-side difference in anterior laxity at a manual maximum force was measured using the KT-2000 Arthrometer®. RESULTS: Among the 125 patients, 99 were ultimately included and 26 were lost to follow-up (follow-up rate: 79%). Eight patients had re-tear (re-tear rate: 8%) and six patients had ACL injuries to the contralateral knee. Three patients did not follow our rehabilitation programme. One patient suffered septic arthritis. These 18 patients were considered ineligible for clinical evaluations. Therefore, clinical evaluations were performed in 81 of the 99 patients (64 were available for direct follow-up and 17 were available for a telephone interview). The follow-up period was 30 ± 10 months (range 24-68 months). According to the IKDC subjective assessment, 48 (59%) and 33 (41%) knees were graded as normal and nearly normal, respectively. A loss of extension (3°-5°) was observed in five patients (8%), whereas one patient (2%) exhibited a loss of flexion (3°-5°). The Lachman test was negative in 63 patients (98%). The pivot shift test was negative in 59 patients (92%). The side-to-side difference in KT value was 0.4 ± 0.7 mm (range - 1-4 mm). CONCLUSION: Anatomical rectangular tunnel ACL reconstruction with a BTB graft using an adjustable-length femoral cortical fixation device provided excellent clinical outcomes both subjectively and objectively more than 2 years after surgery, whereas 8 of the 99 patients had re-tear of the graft. The adjustable-length femoral cortical fixation device could be safely used in anatomical rectangular tunnel ACL reconstruction with a BTB graft. LEVEL OF EVIDENCE: III.

Tibial insertion of the anterior cruciate ligament and anterior horn of the lateral meniscus share the lateral slope of the medial intercondylar ridge: A computed tomography study in a young, healthy population.

BACKGROUND: The central intercondylar ridge (CIR) is an anatomical bony landmark that bisects the slope of the medial intercondylar ridge (MIR) between the tibial insertion of the anterior cruciate ligament (ACL) and anterior horn of lateral meniscus (AHLM) and was recently revealed by computed tomography (CT) evaluation corresponding to histologic slices of cadaveric knees. The purpose of this study was to clarify the shape and size of ACL and AHLM tibial insertion in young, healthy knees using the new bony landmark (CIR) and previously reported landmarks. METHODS: The contralateral healthy knees in 34 ACL-reconstructed patients (18 male patients, 16 female patients, mean age: 24.0 years) were scanned by CT. In the reconstructed coronal/sagittal images, bony landmarks of ACL (anterior: anterior ridge, posterior: blood vessel in tubercle fossa, medial: MIR, lateral: CIR) and AHLM (medial: CIR, lateral: bottom of the slope) were plotted for evaluation. The length of sagittal slices and the width in five coronal slices of the insertion were measured. RESULTS: The ACL insertion consistently showed a boot-like-shape adjacent to the square shape of AHLM on three-dimensional imaging. The mean ACL sagittal length was 14.5 ±â€¯1.9 mm, while the mean ACL widths (in mm) from anterior to posterior were 12.7 ±â€¯2.7, 8.1 ±â€¯1.9, 7.9 ±â€¯2.0, 7.5 ±â€¯1.5, and 7.2 ±â€¯1.6, which was highly correlated with the tibial plateau size. CONCLUSIONS: The boot-like-shape of the ACL tibial footprint insertion shared the slope of MIR with the rectangular shape of AHLM in young, healthy knees. This study may provide useful information for safe tibial tunnel creation at the time of ACL reconstruction.

Loop Length Change of an Adjustable-Length Femoral Cortical Suspension Device in Anatomic Rectangular Tunnel Anterior Cruciate Ligament Reconstruction With a Bone-Patellar Tendon-Bone Graft and Associated Clinical Outcomes.

PURPOSE: To evaluate loop length changes of an adjustable femoral cortical suspensory fixation device and assess the clinical results after anatomic rectangular tunnel anterior cruciate ligament (ART-ACL) reconstruction with a bone-tendon-bone (BTB) graft. METHODS: The study included 50 patients who underwent ART-ACL reconstruction with a BTB graft fixed using the adjustable-length device BTB TightRope for femoral fixation between July 2013 and December 2014. Computed tomography examinations were performed at 1 and 12 weeks after the surgery. Loop length was measured in the reconstructed plane just parallel to the femoral tunnel, including the bone plug and the button. Measurement was performed thrice, and the mean value was used. Loop length change was defined as the difference in loop length between 1 and 12 weeks after the surgery. A paired t test was conducted with the effect size for statistical analysis. At 2 years postoperatively, clinical evaluations, including subjective and objective assessments, were performed. RESULTS: The mean loop lengths at 1 and 12 weeks were 25.77 ± 3.88 mm and 25.81 ± 3.89 mm, respectively, with a significant difference (P = .01). However, the effect size was 0.01, suggesting that the difference was not meaningful. The mean individual loop length change was 0.04 ± 0.13 mm. All individual loop length changes were within the measurement error range. At 2 years postoperatively, 49 patients (98%) were graded as normal or nearly normal according to the International Knee Documentation Committee form. The mean side-to-side difference in anterior laxity at manual maximum force was 0.2 ± 0.5 mm. CONCLUSIONS: The loop length change of an adjustable-length femoral cortical suspension device was negligible after ART-ACL reconstruction with a BTB graft. This ART-ACL reconstruction with a BTB graft using an adjustable-length device could safely provide sufficient stability to the operated knee. LEVEL OF EVIDENCE: Level Ⅳ, therapeutic case series.

Tibial insertions of the anterior cruciate ligament and the anterior horn of the lateral meniscus: A histological and computed tomographic study.

BACKGROUND: A positional relationship between the anterior cruciate ligament (ACL) and the anterior horn of the lateral meniscus (AHLM) has not previously been a topic of interest in the literature because the AHLM is already known to be obviously adjacent to the ACL and is assumed as a lateral border. The objective of this study was to investigate the positional anatomic relationship between the ACL and AHLM by histological evaluation of sequential slices and computed tomography (CT) of the tibial insertion sites. HYPOTHESIS/PURPOSE: The ACL has a specific positional relationship with the AHLM and there is an identifiable distinct bony border between them. The position of the AHLM could be an important and useful landmark for accurate tibial tunnel positioning in anatomical ACL reconstruction. STUDY DESIGN: Descriptive laboratory study. METHODS: Twelve ACL-intact knees from embalmed cadavers were used in this study. Six knees were sectioned into four slices for histologic examination in the coronal planes parallel to the AHLM alignment. Before sectioning, these knees were subjected to three-dimensional (3-D) volume-rendering CT. Each of the four slices demonstrated the insertion area of the ACL relative to the position of the AHLM. Each histologic slice was compared with the corresponding CT image. Only histological examination in the sagittal planes was performed in the other six knees. RESULTS: The ACL fibres were broadly attached at the region anterior to the AHLM. However, the ACL and AHLM shared a clear border identifiable on the coronal CT images and appeared as a prominence of the bony ridge on the 3-D CT images. No dense ACL fibres were attached to the region posterior to the AHLM. Based on the histological data, the geometry of the ACL tibial insertion was L-shaped along the AHLM. CONCLUSION: The ACL and AHLM have a specific positional relationship not only in the mediolateral direction but also anteroposteriorly. The AHLM serves not only as a lateral border, but also as a useful reference in an anterioposterior direction for tunnel positioning in ACL reconstruction. Specifically, the ACL fibres were found to be broadly attached onto the bony surface in the region anterior to the AHLM and there was no firm attachment of the ACL in the region posterior to the AHLM on the tibial side, which is useful in avoiding posterior tunnel placement.

Healing of tibial bone tunnels after bone grafting for staged revision anterior cruciate ligament surgery: A prospective computed tomography analysis.

AIM: To quantify healing of tibial bone tunnels after bone grafting in two-stage ACL reconstruction revision. METHODS: Ten consecutive patients underwent autogenous bone grafting prior to ACL reconstruction revision (four females and six males, average age 28years). The indications for two-stage surgery were as follows: (1) the enlargement of the tibial tunnel aperture was >20mm in diameter or, (2) the existing tunnel was overlapped with the optimal tunnel and positioned more than a half tunnel diameter posterior to the optimal position. An autogenous iliac bone block was driven into a new tunnel. CT examinations were performed at three, 12 and 24weeks after bone grafting. Evaluations were performed on 15 axial planes at one-millimeter intervals from the articular surface perpendicular to the long axis of the tibia using the following three parameters: occupying ratio (OR), union ratio (UR), and bone mineral density (BMD) of grafted bone. RESULTS: The average ORs were 81, 85 and 94%, and the average URs were 49, 75 and 89% at three, 12 and 24weeks, respectively. Each parameter significantly increased over time. The average BMD was 510 and 571mg/cm(3) at 12 and 24weeks, respectively, with a significantly higher value at 24weeks. CONCLUSION: The average ORs, URs and BMD at 24weeks after bone grafting were higher than those at 12weeks, which suggests that at 24weeks after bone grating, the condition of the patients' beds becomes favorable for safe implantation and fixation of ACL graft revision. LEVEL OF EVIDENCE: Case series Level IV.

Early reconstruction should be considered in younger patients with symptomatic mucoid degeneration of the anterior cruciate ligament.

BACKGROUND: Mucoid degeneration of the anterior cruciate ligament (ACL) is mostly observed in middle-aged patients with knee pain and limited range of motion. Although arthroscopic resection of the degenerated ACL is the treatment of choice following the failure of conservative management, the extent of the excision and subsequent ACL reconstruction for postoperative knee instability remains controversial. CASE REPORTS: We present four cases of mucoid degeneration of the ACL in patients aged <40 years, and suggest a suitable treatment strategy for younger patients. All four patients (mean age, 33.8 years) were diagnosed with mucoid degeneration of the ACL based on characteristic clinical symptoms and magnetic resonance imaging. Arthroscopic resection of the affected portion of the ACL was performed as follows: partial resection in two cases with limited hypertrophy, and total ACL resection in the remaining two cases with degeneration involving the entire ligament. Preoperative symptoms disappeared in all cases after resection of the lesions. In the two patients with partial resection, the ACL was completely torn during subsequent sports activities despite showing no symptoms of instability for 2 years postoperatively. All four patients, including the two treated by total resection, underwent ACL reconstruction using an autogenous hamstring tendon. CONCLUSION: Considering the rupture of residual ACL fibres after partial resection and the inevitability of total ACL resection due to degeneration of the entire ligament, ACL reconstruction should be considered in younger patients with symptomatic mucoid degeneration of the ACL.

Patellar mobility can be reproducibly measured using ultrasound.

The present study was performed to examine the reliability of ultrasound in evaluating patellar mobility in the superior-inferior direction. Twelve healthy men volunteered for the study. Patellar mobility in the superior-inferior direction during isometric knee extension contraction with the knee immobilized in a semi-flexed knee brace was measured using ultrasound. Both intra-observer and inter-observer reliability were assessed by intra-class correlation coefficients (ICCs). Bland-Altman analysis was used for assessing agreement between measurements. ICC values were excellent for both intra-observer and inter-observer reliability at 0.97 and 0.93, respectively. In 95 % of measurements, the same observer measured within -0.55 to 0.61 mm, while different observers measured within -0.82 to 0.85 mm. In conclusion, patellar mobility in the superior-inferior direction during an isometric knee extension exercise can be reproducibly measured using ultrasound. THE LEVEL OF EVIDENCE: VI (basic study of a novel evaluation method).

Anterior knee symptoms after double-bundle ACL reconstruction with hamstring tendon autografts: an ultrasonographic and power Doppler investigation.

PURPOSE: Anterior knee pain related to the donor site is a frequent complication of anterior cruciate ligament reconstruction (ACLR) with bone-patellar tendon-bone autograft tissue. Even when hamstring tendon (HT) grafts are used instead, symptoms such as mild pain and discomfort can still occur. The purpose of this study was to elucidate the pathophysiology of anterior knee symptoms after ACLR with HT autografts. METHODS: Fifty-seven patients (22 men and 35 women; mean age, 24.7 years) who underwent anatomic double-bundle ACLR with HT autografts were examined 6 months post-operatively. The presence of anterior knee symptoms, anterior knee laxity, range of motion, and muscle strength were assessed. Changes in patellar tendon and infrapatellar fat pad (IFP) morphology and blood flow were also evaluated using ultrasound. Potential variables affecting the presence of anterior knee symptoms were subjected to univariate analysis and multivariate logistic regression analysis to identify independent risk factors. RESULTS: Six months post-operatively, the total incidence of anterior knee symptoms was 56.1 % (32/57). According to univariate analysis, age, quadriceps strength, and increased blood flow in the IFP were significantly associated with the presence of anterior knee symptoms. Multivariate logistic regression analysis revealed that increased blood flow in the IFP was an independent factor for the presence of anterior knee symptoms (odds ratio 5.0; 95 % confidence interval 1.3-19.9). There were no significant findings inside the patellar tendon. CONCLUSIONS: Increased blood flow in the IFP was identified as an independent factor for the presence of anterior knee symptoms 6 months after ACLR with HT autografts. The ultrasound evaluation can help to define precisely the origin of anterior knee symptoms after ACLR with HT autografts. LEVEL OF EVIDENCE: Case series with no comparison groups, Level IV.

MRI analysis of single-, double-, and triple-bundle anterior cruciate ligament grafts.

PURPOSE: The purpose of the study was to evaluate the entire course of ACL grafts on coronal oblique MR images, focusing on differences in graft morphology and graft-to-tunnel healing among single-bundle (SB), double-bundle (DB), and triple-bundle (TB) reconstructions. METHODS: Eighty-three patients underwent anatomical ACL reconstruction using the semitendinosus tendon. SB reconstruction was performed on 20 patients, DB on 29 patients, and TB on 34 patients. The anteromedial-bundle (AMB) and posterolateral-bundle (PLB) images were extracted from coronal oblique images of grafts at 6 months to visualize their entire course. Signal intensity of grafts was measured independently in three regions: (1) intra-femoral tunnel region, (2) intra-articular region, and (3) intra-tibial tunnel region, followed by calculation of the signal-to-noise quotient (SNQ). To evaluate graft-to-tunnel healing, T2-weighted images were examined for the presence of a high signal-intensity lesion between the graft and bone tunnel around the tunnel aperture. RESULTS: AMB images showed that SB graft was thick throughout the entire course, while DB graft was thinner than SB graft. TB graft showed a fan shape approaching the tibial tunnels. The SNQ in the femoral tunnel of SB graft was significantly lower than in the DB and TB grafts. High signal-intensity lesions were frequently observed around the femoral tunnel aperture in PLB images of DB and TB grafts compared to SB grafts. CONCLUSION: Gross morphology of TB grafts resembled that of the natural ACL. However, the graft-to-tunnel healing around the femoral tunnel seemed to be insufficient in PLB images of DB and TB compared to SB grafts.

Transarticular drilling for stable juvenile osteochondritis dissecans of the medial femoral condyle.

PURPOSE: Drilling is the most common operative treatment for stable juvenile osteochondritis dissecans (OCD) of the knee. However, prognostic factors remain unclear because of lack of precise radiographic and histopathologic investigations. The purpose of this study was to evaluate the clinical results and prognostic factor of the arthroscopic drilling for juvenile OCD lesions at the medial femoral condyle (MFC), using computed tomography (CT) images. METHODS: Eighteen skeletally immature patients (boys, n = 16; girls, n = 2, mean age, 12 years) underwent arthroscopic antegrade transarticular drilling for a total of 19 OCD lesions of MFC. Functional outcomes were evaluated with the Lysholm score at follow-up (mean, 30 months). Preoperative osteochondral condition and postoperative healing were evaluated by CT images. RESULTS: All 18 patients returned to their previous level of sports activity and showed excellent functional outcomes (mean Lysholm score, 77.2 ± 9.4 preoperative vs. 99.5 ± 1.6 postoperative). There were 10 osteochondral lesions and 9 subchondral bone defect lesions under preoperative CT examination. Postoperatively, 15 of 19 lesions healed completely at a mean of 6 months; however, the remaining four lesions (all osteochondral types) did not achieve complete radiographic healing after 2 years. CONCLUSION: Transarticular drilling for stable juvenile OCD produced excellent functional outcomes. However, the osteochondral type may influence radiographic outcome. LEVEL OF EVIDENCE: Case series, Level IV.