Ten-Year Clinical Outcomes of Endoscope-Assisted Minimally Invasive Surgical Decompression for Lumbar Spinal Stenosis with Degenerative Spondylolisthesis and Comparison with Conservative Treatment.

Introduction: This study aimed to evaluate the 10-year clinical outcomes of endoscope-assisted, minimally invasive surgical (MIS) decompression for lumbar spinal canal stenosis (LSS) with lumbar degenerative spondylolisthesis (DS) and to compare the radiographic changes in patients who underwent this procedure with those who underwent conservative therapy at 10-year follow-up. Methods: Between April 2007 and April 2010, 347 consecutive patients with DS and evidence of LSS underwent conservative treatment first from 2 to 4 weeks. The 114 patients who failed conservative treatment were then treated surgically by endoscope-assisted MIS decompression. Of them, 91 patients were followed for more than 10 years (group S), and 146 of the 233 patients treated conservatively were followed for more than 10 years (group C). Clinical outcomes of endoscope-assisted MIS decompression were assessed using the Short Form Health Survey-36 score (SF-36), the Roland Morris Disability Questionnaire (RDQ), and the neurological leg symptoms of the Japanese Orthopaedic Association Score (JOA score). Radiographic changes of the two groups were assessed by %slip, dynamic %slip, range of motion (ROM), and the height of the disc (DH) on plain radiographs. Results: Significant improvements in clinical outcomes on the SF-36, RDQ, and neurological leg symptoms of the JOA were observed. Radiographic assessment did not show significant differences in the assessed items between the two groups at baseline and after last treatment. Both groups had significantly decreased ROM and DH. Conclusions: The 10-year clinical outcomes of endoscope-assisted MIS decompression for DS were generally good. Furthermore, on radiographic comparison, the progress of spondylolisthesis after this procedure was virtually the same as in the natural course of the disease at 10-year follow-up.

Effect of Postoperative Non-Weight-Bearing in Trochanteric Fracture of the Femur: A Retrospective Cohort Study Using Propensity Score Matching.

Introduction: The effects of postoperative early weight-bearing (WB) on walking ability, muscle mass, and sarcopenia have been investigated. Postoperative WB restriction is also reportedly associated with pneumonia and prolonged hospitalization; however, its effect on surgical failures has not been studied. This study aimed to assess whether WB restriction after surgery for trochanteric fracture of the femur (TFF) is useful in preventing surgical failure, considering the unstable fracture type, quality of intraoperative reduction, and tip-apex distance. Patients and Methods: This retrospective analysis included 301 patients admitted to a single institution between January 2010 and December 2021, diagnosed with TFF, and who underwent femoral nail surgery. Eight patients were excluded, and finally 293 patients were included in the study. Propensity score (PS) matching yielded 123 cases; 41 patients in the non-WB (NWB) group and 82 patients in the WB group were included in the final analysis. The primary outcome was surgical failure (cutout, nonunion, osteonecrosis, and implant failure). The secondary outcomes were medical complications (pneumonia, urinary tract infection, stroke, and heart failure), change in walking ability, period of hospitalization, and sliding distance of the lag screw. Results: Five surgical complications occurred in the NWB group and two in the WB group, with significantly more surgical complications in the NWB group (P = .041). Cutout occurred in two cases, each in the NWB and WB groups. Two cases of nonunion and one case of implant failure occurred in the NWB group, but not in the WB group. Osteonecrosis did not occur in both groups. The secondary outcomes were not significantly different between the two groups. Conclusions: The results of this retrospective cohort study using a PS matching approach showed that WB restriction after TFF surgery could not decrease the incidence of surgical failures.

Effectiveness of Adhering Adipose-Derived Stem Cells to Defective Cartilage in Promoting Cartilage Regeneration in a Rabbit Model.

PURPOSE: To evaluate the therapeutic effect of using a local adherent technique to transplant adipose-derived stem cells (ADSCs) for cartilage regeneration in a rabbit model for patients with traumatic damage or osteochondritis dissecans. METHODS: Cartilage defects were created in the trochlear groove of 60 adult white rabbit knees. The rabbits were either left untreated (control group), treated with intra-articularly injected ADSCs (injected group), or treated by adhering ADSCs (adherent group). The 3 groups were compared at 4, 12, and 24 weeks postoperatively using the International Cartilage Repair Society macroscopic scoring system and a modified Wakitani histologic grading system to quantitatively evaluate the regenerated cartilage. The degree of defect repair, integration to the border zone, macroscopic appearance, cell morphology, matrix staining, surface regularity, cartilage thickness, and integration of the donor with the host were evaluated. RESULTS: The mean International Cartilage Repair Society scores in the control, injected, and adherent groups were 6.4 ± 2.9, 7.6 ± 0.8, and 7.6 ± 1.4, respectively, at 4 weeks; 6.2 ± 2.4, 8.2 ± 1.5, and 9.6 ± 1.0, respectively, at 8 weeks; and 7.6 ± 1.0, 8.4 ± 1.4, and 10.2 ± 1.7, respectively, at 24 weeks. Although the scores were higher in the adherent group, no significant difference was noted. The mean modified Wakitani scores in the control, injected, and adherent groups were 3.8 ± 2.0, 5.1 ± 1.8, and 7.8 ± 1.3, respectively, at 4 weeks (P = .041); 5.1 ± 1.0, 5.4 ± 2.7, and 9.6 ± 1.4, respectively, at 12 weeks (P = .016); and 5.4 ± 1.0, 5.9 ± 1.5, and 9.8 ± 1.8, respectively, at 24 weeks (P = .007). CONCLUSIONS: The histologic modified Wakitani scores showed that adhering ADSCs to osteochondral cartilage defects was more effective than intra-articular injection for promoting cartilage regeneration. CLINICAL RELEVANCE: Local adhesion of ADSCs can promote cartilage regeneration and may be a treatment option for cartilage repair.

A Scaffold-Free Allogeneic Construct From Adipose-Derived Stem Cells Regenerates an Osteochondral Defect in a Rabbit Model.

PURPOSE: To determine whether an osteochondral defect could be healed histologically by implanting allogeneic 3-dimensionally formed adipose-derived stem cells (ADSCs) in a rabbit model. METHODS: Thirty Japanese white rabbits (aged 15-17 weeks) were assigned to 1 of 2 groups. An osteochondral defect (diameter, 4.8 mm; depth, 3 mm) was created in the trochlear groove of the knee using a drill. The defects were left empty in the control group and were filled with cylindrical plugs of allogeneic ADSCs extracted from adipose tissue in the experimental group. Macroscopic scoring, histologic scoring, and immunohistologic stainability of type II collagen were evaluated at 4, 8, and 12 weeks postoperatively. RESULTS: The macroscopic scores of the healing tissue in the experimental group were significantly greater than those in the control group at 12 weeks (P = .031). Histologically, safranin O staining was noted at 4 weeks and increased gradually over time in the experimental group. The modified International Cartilage Repair Society histologic score in the experimental group was significantly higher than that in the controls at 8 and 12 weeks (14 vs 9 at 8 weeks [P = .008], 18 vs 10 at 12 weeks [P = .007]). The implanted tissue was positive for type II collagen, and stainability increased gradually over time. CONCLUSIONS: The 3-dimensional scaffold-free allogeneic ADSCs implanted into the osteochondral defect survived, adhered to the defect, increased the stainability of type II collagen gradually over time, and promoted histologic healing in a rabbit model. CLINICAL RELEVANCE: ADSC implantation designed to promote osteochondral healing may play an important role in osteochondral healing.

Poor static balance is a risk factor for non-contact anterior cruciate ligament injury.

BACKGROUND: This prospective study aimed to investigate the relationship between static balance and the incidence of non-contact anterior cruciate ligament (ACL) injury in female high school athletes. METHODS: This study included 276 female high school handball or basketball players. At the time of admission, each subject's static balance was measured with a gravicorder, and the incidence of non-contact ACL injury was investigated in the 3 years until the student graduated. The measured parameters of postural sway were locus length per time (the distance that a center of gravity of the foot pressure moves per second) and environmental area (AR: the area surrounded by the integumentary covering of the trace of the center of gravity). Twenty-seven players (9.8%) experienced an ACL injury during the 3-year observation period. Twenty-four injured players sustained a non-contact injury and three injured players sustained a contact injury. In this study, the three contact injury players were excluded. We compared the differences in the static balance between injured and uninjured players. RESULTS: The locus length per time was significantly longer in injured than in uninjured players (p = 0.046). Though there was no statistically significant difference between the two groups in AR (p = 0.190), AR tended to be larger in the ACL injured group. CONCLUSIONS: This result shows that poor static balance is a risk factor for non-contact ACL injury.

Two-dimensional motion analysis of dynamic knee valgus identifies female high school athletes at risk of non-contact anterior cruciate ligament injury.

PURPOSE: Female athletes are at greater risk of non-contact ACL injury. Three-dimensional kinematic analyses have shown that at-risk female athletes have a greater knee valgus angle during drop jumping. The purpose of this study was to evaluate the relationship between knee valgus angle and non-contact ACL injury in young female athletes using coronal-plane two-dimensional (2D) kinematic analyses of single-leg landing. METHODS: Two hundred ninety-one female high school athletes newly enrolled in basketball and handball clubs were assessed. Dynamic knee valgus was analysed during single-leg drop jumps using 2D coronal images at hallux-ground contact and at maximal knee valgus. All subjects were followed up for 3 years for ACL injury. Twenty-eight (9.6%) of 291 athletes had ACL rupture, including 27 non-contact ACL injuries. The injured group of 27 knees with non-contact ACL injury was compared with a control group of 27 randomly selected uninjured knees. The relationship between initial 2D movement analysis results and subsequent ACL injury was investigated. RESULTS: Dynamic knee valgus was significantly greater in the injured group compared to the control group at hallux-ground contact (2.1 ± 2.4 vs. 0.4 ± 2.2 cm, P = 0.006) and at maximal knee valgus (8.3 ± 4.3 vs. 5.1 ± 4.1 cm, P = 0.007). CONCLUSION: The results of this study confirm that dynamic knee valgus is a potential risk factor for non-contact ACL injury in female high school athletes. Fully understanding the risk factors that increase dynamic knee valgus will help in designing more appropriate training and interventional strategies to prevent injuries in at-risk athletes. LEVEL OF EVIDENCE: Prognostic studies, Level II.

Conscious performance and arthroscopic findings in athletes with anterior cruciate ligament injuries treated via conservative therapy during the competitive season.

PURPOSE: Athletes often receive conservative treatment for injured anterior cruciate ligaments (ACLs) so that they can continue to play to the end of their season. The purpose of this study was to examine the conscious performance and arthroscopic findings of athletes who received conservative therapy for ACL injuries. METHODS: Forty-two patients with ACL injuries underwent conservative treatment. After the season ended, ACL reconstruction was performed. We examined the following parameters: (1) time required for return to competition after injury, (2) conscious performance after return to competition, (3) whether the injured knee gave way during conservative therapy or after return to competition, and (4) cause of performance deterioration if applicable. To determine conscious performance, patients were asked to rate their performance after therapy relative to their performance before injury. RESULTS: Thirty-eight of the 42 patients (90.5%) returned to competition after conservative treatment. The mean time to return was 13.8 ± 7.6 weeks, and the mean conscious performance score was 58.4 ± 16.5%. Thirty-eight patients (90.5%) experienced their knee giving way, of whom 36 (94.9%) stated that fear of their knee giving way hampered their performance. At the time of ACL reconstruction, 9 patients had chondral injuries and 22 patients had meniscus injuries. CONCLUSION: Most athletes with damaged ACLs returned to the field within the same season after conservative treatment. However, conscious performance was only about 60%. It is possible that knees giving way caused secondary meniscus and joint cartilage damage. Therefore, conservative treatment of individuals with ACL injuries should be considered carefully.

Scaffold-Free Tissue-Engineered Allogenic Adipose-Derived Stem Cells Promote Meniscus Healing.

PURPOSE: To determine whether meniscal tissue could be healed histologically by the implantation of allogenic three-dimensional formed adipose-derived stem cells (ADSCs) in a rabbit model of partial meniscectomy. METHODS: Forty Japanese white rabbits (aged 15-17 weeks) were assigned to 2 groups. Defects 1.5 mm in diameter were created in the anterior horn of the medial menisci. The defects were left empty in the control group and were filled with cylindrical plugs of allogenic ADSCs extracted from adipose tissue in the experimental group. Macroscopic scoring (range, 0-3), histological scoring (range, 0-12), and immunohistological stainability of type I collagen were evaluated at 2, 4, 8, and 12 weeks postoperatively (n = 5 rabbits for each week). RESULTS: Macroscopically, the height of the healing tissue in the experimental group was significantly greater than that of the control group at 2 weeks (3 vs 0, P = .01), 4 weeks (3 vs 1, P = .01), and 8 weeks (3 vs 2, P = .02). Histologically, safranin-O staining was noted at 2 weeks and increased gradually over time in the experimental group. In contrast, the intensity of staining was lower in controls at all weeks. Tissue quality scores were significantly higher in the experimental group than in the controls at all weeks (3 vs 0 at 2 weeks [P = .00009], 4.5 vs 2 at 4 weeks [P = .00023], 9 vs 5 at 8 weeks [P = .0047], 10.5 vs 6 at 12 weeks [P = .00026]). The implanted tissue was positive for type I collagen, and stainability was increased gradually over time. CONCLUSIONS: Three-dimensional scaffold-free allogenic ADSCs implanted into a 1.5-mm avascular meniscal defect survived, adhered to the defect, and promoted histological meniscus healing in a rabbit model. CLINICAL RELEVANCE: ADSC implantation designed to promote meniscal healing may play an important role as a tool for meniscus healing.

The cross-sectional shape of the fourfold semitendinosus tendon is oval, not round.

BACKGROUND: The looped side of the semitendinosus tendon (ST) graft (i.e., the side inserted into the femoral tunnel during anterior cruciate ligament reconstruction) appears to be oval rather than round. The purpose of this study was to investigate the cross section of the fourfold semitendinosus tendon graft and, more specifically, the differences in pressure exerted by a rounded rectangular tunnel versus a round femoral tunnel. METHODS: Seven STs were harvested from cadaveric knees and a fourfold ST graft was made. Aluminum cubes with round or rectangular tunnels containing four-way pressure-sensitive conductive sensors (vertically and bilaterally) were used. The area of both cubes was the same. The graft was inserted into the tunnels 15 mm from the looped edge. After measuring pressure, the graft was fixed using ultraviolet-curing acrylic resin and was cut at 7.5 mm and 15 mm from the lapel edge. The area, axes for the best fitting ellipse of the cross-section, and ellipticity of the axes were measured. RESULTS: In the round tunnel, the mean contact pressure was 287.0 ± 136.7 gf at the bilateral sensor; there was no contact pressure detected by the vertical sensor. In the rounded rectangular tunnel, the mean contact pressure was 260.9 ± 186.4 gf at the bilateral sensor and 352.9 ± 49.5 gf at the vertical sensor. Ellipticity was 1.25 ± 0.13 at 7.5 mm, and 1.17 ± 0.07 at 15 mm from the lapel edge of the graft. CONCLUSIONS: The cross-sectional shape of the fourfold ST graft was not round, but oval. Moreover, the rounded rectangular tunnel was more fitted to the graft than the round tunnel.

Computed tomography value and tunnel enlargement of round and rounded rectangular femoral bone tunnel for anterior cruciate ligament reconstruction.

INTRODUCTION: We developed a novel technique for anatomical single-bundle anterior cruciate ligament (ACL) reconstruction: creation of a rounded rectangular femoral bone tunnel. The purpose of this study was to compare the computed tomography (CT) value and tunnel enlargement ratio of the femoral bone tunnel with those of round tunnel ACL reconstruction. MATERIALS AND METHODS: We included 39 knees that underwent round tunnel ACL reconstruction and 42 that underwent rounded rectangular ACL reconstruction. To evaluate the CT value, we compared the CT images approximately 1 week after surgery. Making a parallel slice toward the opening of bone tunnels to a depth of 3 mm, we evaluated the CT value of eight directions in the bone tunnel wall. To evaluate tunnel enlargement, we compared CT images approximately 1 week after surgery with images taken 3 months after surgery. Using a parallel slice toward the opening of the bone tunnel, we measured the bone tunnel area and calculated the tunnel enlargement ratio. The level of significance was P < 0.05, and the t test was used for statistical analyses. RESULTS: The CT value was significantly increased for the rounded rectangular tunnel in comparison with the round tunnel in almost all directions (P < 0.05). The rounded rectangular tunnel area enlargement ratio was significantly lower (round, 110 ± 38 %; rounded rectangular, 73 ± 37 %; P = 0.001). CONCLUSION: The rounded rectangular tunnel could have a compression effect on the cancellous bone and reduce enlargement of the bone tunnel.

Psychological traits regarding competitiveness are related to the incidence of anterior cruciate ligament injury in high school female athletes.

BACKGROUND: The purpose of this study was to investigate the relationship between psychological competitive ability and the incidence of noncontact ACL injuries among high school female athletes. METHODS: A three-year prospective cohort study was conducted using 300 15-year-old high school female athletes with no previous injuries or symptoms in their lower limbs (106 handball players and 194 basketball players). At baseline, their psychological competitive abilities were assessed using a self-administered questionnaire-the Diagnostic Inventory of Psychological Competitive Ability (DIPCA.3). After the baseline examination was performed at high school entry, all players were prospectively followed for 36months to document any subsequent incidence of ACL injury, according to their coaches. An unpaired t-test with Welch's correction was performed to compare the differences in the psychological competitive abilities between the injured and uninjured players. RESULTS: Of the 300 players, 25 (8.3%) experienced a noncontact ACL injury during the three-year observation period. The injured players had significantly higher total DIPCA.3 scores for psychological competitive ability than the uninjured players (169.9±18.8 vs. 159.2±21.6, P=.036). Additionally, the injured players had significantly higher scores than the uninjured players in the following categories: aggressiveness, volition for self-realization, volition for winning, judgment, and cooperation. However, no significant differences were observed in patience, self-control, ability to relax, concentration, confidence, decision, and predictive ability. CONCLUSIONS: High psychological competitive ability was associated with the incidence of noncontact ACL injuries in high school female athletes. LEVEL OF EVIDENCE: Level II (prospective cohort study).

Changes in muscle activity after performing the FIFA 11+ programme part 2 for 4 weeks.

Changes in muscle activity were evaluated by positron emission tomography-computed tomography (PET-CT) after performing part 2 of the Fédération Internationale de Football Association's 11+ programme (11+) for 4 weeks. Eleven males performed part 2 of the 11+ for 20 min before and after 37 MBq of (18)F-fluorodeoxyglucose (FDG) was injected intravenously. PET-CT images were obtained 50 min after FDG injection. The participants were then instructed to perform part 2 of the 11+ 3 times per week for 4 consecutive weeks, after which another set of PET-CT images was obtained following the same procedure. Regions of interest were defined within 30 muscles. The standardised uptake value (SUV) of FDG by muscle tissue per unit volume was calculated, and FDG accumulation was compared between pre- and post-training PET-CT results. Performing part 2 of the 11+ for 4 weeks increased mean SUV in the sartorius, semimembranosus, biceps femoris, abductor hallucis, and flexor hallucis brevis muscles (P < 0.05). In conclusion, routinely performing part 2 of the 11+ for 4 weeks increased glucose uptake related to muscle activity in the hamstrings and hallux muscles. We speculate that there is some possibility of this change of muscle activity contributing to a decrease in sports-related injuries.

Ultrasonography imaging of the anterolateral ligament using real-time virtual sonography.

BACKGROUND: The anterolateral ligament (ALL) functions as a stabilizer in the internal rotation of the knee. Previous studies have reported the ALL can be identified using magnetic resonance imaging (MRI); however, there are no reports on using ultrasonography (US) for this purpose. Real-time virtual sonography (RVS) uses magnetic navigation and computer software for the synchronized display of real-time US and multiplanar reconstruction MRI images. This study investigated the ability of using US with RVS to evaluate the ALL. METHODS: Nine healthy subjects were enrolled. The Digital Imaging Communications in Medicine MRI dataset was loaded into the Hitachi Aloka Preirus, and US images were displayed on the same monitor. When the ALL was identified using MRI, the monitor was frozen to evaluate the ALL. The ALL was divided into the femoral, meniscal, and tibial portions. The portions and thickness of the ALLs and the lateral inferior genicular artery (LIGA), a landmark for the ALL, were evaluated. RESULTS: All portions of the ALL could be identified using MRI. Using US, the tibial portion of the ALL was detected in all subjects and the femoral portion was detected in seven subjects; however, the meniscal portions could not be identified. The average ALL thickness as measured by US was 1.3±0.1 mm and the LIGA was identified in all cases. CONCLUSIONS: Most portions of the ALL can be identified using US. As most ALL injuries occur at the femoral or tibial portion, US may be useful as a diagnostic tool for ALL injury. LEVEL OF EVIDENCE: 4.

Effects of the belt electrode skeletal muscle electrical stimulation system on lower extremity skeletal muscle activity: Evaluation using positron emission tomography.

BACKGROUND: Lower-extremity muscle weakness in athletes after lower limb trauma or surgery can hinder their return to sports, and the associated muscle atrophy may lead to deterioration in performance after returning to sports. Recently, belt electrode skeletal muscle electrical stimulation (B-SES) which can contract all the lower limb skeletal muscles simultaneously was developed. However, no study has evaluated skeletal muscle activity with B-SES. Since only superficial muscles as well as a limited number of muscles can be investigated using electromyography, we investigated whether positron emission tomography (PET) can evaluate the activity of all the skeletal muscles in the body simultaneously. The purpose of this study was to evaluate the effectiveness of the B-SES system using PET. METHODS: Twelve healthy males (mean age, 24.3 years) were divided into two groups. The subjects in the control group remained in a sitting position for 10 min, and [(18)F] fluorodeoxyglucose (FDG) was intravenously injected. In the exercise group, subjects exercised using the B-SES system for 20 min daily for three consecutive days as a pre-test exercise. On the measurement day, they exercised for 10 min, received an injection of FDG, and exercised for another 10 min. PET-computed tomography images were obtained in each group 60 min after the FDG injection. Regions of interest were drawn in each lower-extremity muscle. We compared each skeletal muscle metabolism using the standardized uptake value. RESULTS: In the exercise group, FDG accumulation in the gluteus maximus, gluteus medius, gluteus minimus, quadriceps femoris, sartorius, and hamstrings was significantly higher than the muscles in the control (P < 0.05). CONCLUSION: Exercise with B-SES increased the skeletal muscle activity of the gluteal muscles as well as the most lower-extremity muscles simultaneously.

Ipsilateral Medial and Lateral Discoid Meniscus with Medial Meniscus Tear.

INTRODUCTION: Discoid meniscus is a well-documented knee pathology, and there are many cases of medial or lateral discoid meniscus reported in the literature. However, ipsilateral concurrent medial and lateral discoid meniscus is very rare, and only a few cases have been reported. Herein, we report a case of concurrent medial and lateral discoid meniscus. CASE REPORT: A 27-year-old Japanese man complained of pain on medial joint space in his right knee that was diagnosed as a complete medial and lateral discoid meniscus. In magnetic resonance imaging, although the lateral discoid meniscus had no tear, the medial discoid meniscus had a horizontal tear. Arthroscopic examination of his right knee similarly revealed that the medial discoid meniscus had a horizontal tear. In addition, the discoid medial meniscus also had an anomalous insertion to the anterior cruciate ligament, and there was also mild fibrillation of the medial tibial cartilage surface. We performed arthroscopic partial meniscectomy for the torn medial discoid meniscus but not for the asymptomatic lateral discoid meniscus. The latest follow-up at 18 months indicated satisfactory results. CONCLUSION: We report a rare case of ipsilateral medial and lateral discoid meniscus with medial meniscus tear. The medial discoid meniscus with tear was treated with partial meniscectomy, whereas the lateral discoid meniscus without tear was only followed up.

Technique of anatomical single bundle ACL reconstruction with rounded rectangle femoral dilator.

BACKGROUND: This study aimed to present a new technique for anatomical single bundle anterior cruciate ligament (ACL) reconstruction. We developed an original rounded rectangular dilator set to create rounded rectangular femoral tunnels. This technique can increase the femoral tunnel size without roof impingement, and has the potential to reduce the graft failure rate. We investigated the tunnel position and the incidence of intraoperative complications. METHOD: The presented technique is anatomical single bundle ACL reconstruction using a semitendinosus graft (with or without the gracilis tendon). The tunnel was drilled via an additional medial portal. Rounded rectangular tunnels were created using a special dilator. Tibial tunnels were created using conventional rounded tunnels. Fixation was achieved using a suspensory device on the femoral side and a plate and screw on the tibial side. PATIENTS: Fifty patients underwent this surgery, and intraoperative complications were investigated. The femoral tunnel positions were documented postoperatively from computed tomography scans using the quadrant method. The tibial tunnel positions (anterior-to-posterior, medial-to-lateral) were documented using intraoperative X-ray scans. RESULTS: Only one patient had a partial posterior tunnel wall blowout. The femoral tunnel length varied between 30 and 40mm (mean, 34.9±3.3mm). All femoral and tibial tunnels were located within the area of the anatomical ACL insertions. CONCLUSION: We did not experience any serious intraoperative complications during anatomical single bundle ACL reconstruction using a rounded rectangle dilator, and the resulting locations of the femoral and tibial tunnels were within the anatomical ACL footprint. LEVEL OF EVIDENCE: Level IV.

Precise risk factors for Osgood-Schlatter disease.

INTRODUCTION: A number of studies have examined the risk factors for Osgood-Schlatter disease (OSD). Studies on risk factors have not necessarily accurately demonstrated the risk factors of this disease because they were not prospective cohort studies or the populations in the studies were not categorized by the skeletal maturation of the tibial tuberosity. We can identify the precise risk factors for OSD by performing a prospective cohort study of a group of asymptomatic patients in particular times of adolescent using ultrasonography. In the present study, we aimed to investigate the precise risk factors for OSD. METHODS: For all examinations, we used a 3-stage classification for tibial tuberosity development observed on ultrasonography: sonolucent (stage S), individual (stage I), and connective stages (stage C). Among 150 players with 300 knees, we included 37 male players with 70 knees at asymptomatic stage I on the first examination. We re-examined the included knees 1 year after the first examination and compared 10 knees with OSD (OSD group) and 60 knees without OSD (control group). Height, body weight, body mass index, tightness of the quadriceps femoris and hamstring muscles, muscle strength during knee extension, and flexion were assessed during the first medical examination. RESULTS: The incidence of OSD was 14.3 % in this 1-year cohort study. A significant difference was found in body weight, quadriceps muscle tightness, and muscle tightness and strength during knee extension between the 2 groups. The precise risk factors for OSD were increased, namely the quadriceps femoris muscle tightness and strength during knee extension and flexibility of the hamstring muscles, using logistic regression analysis. CONCLUSIONS: This information may be useful for teaching quadriceps stretching in preadolescent male football players with stage I.

Common Peroneal Nerve Palsy with Multiple-Ligament Knee Injury and Distal Avulsion of the Biceps Femoris Tendon.

A multiple-ligament knee injury that includes posterolateral corner (PLC) disruption often causes palsy of the common peroneal nerve (CPN), which occurs in 44% of cases with PLC injury and biceps femoris tendon rupture or avulsion of the fibular head. Approximately half of these cases do not show functional recovery. This case report aims to present a criteria-based approach to the operation and postoperative management of CPN palsy that resulted from a multiple-ligament knee injury in a 22-year-old man that occurred during judo. We performed a two-staged surgery. The first stage was to repair the injuries to the PLC and biceps femoris. The second stage involved anterior cruciate ligament reconstruction. The outcomes were excellent, with a stable knee, excellent range of motion, and improvement in the palsy. The patient was able to return to judo competition 27 weeks after the injury. To the best of our knowledge, this is the first case report describing a return to sports following CPN palsy with multiple-ligament knee injury.

Repair and augmentation of a spontaneous patellar tendon rupture in a patient with Ehlers-Danlos syndrome: a case report.

INTRODUCTION: Disruption of the knee extensor mechanism is a serious disorder that requires prompt treatment. It often occurs in the form of a patellar tendon rupture. It may occur in association with systemic disease or after administration of corticosteroids or fluoroquinolones. These conditions can cause tendon weakness, and consequent ruptures usually require both repair and augmentation. This paper reports on repair and augmentation for treating patellar tendon rupture in patients with Ehlers-Danlos syndrome (EDS). CASE REPORT: We report a patellar tendon rupture in a 27-year-old man with EDS, which occurred in the midsubstance of the patella. As the patient has tendon weakness, extensive repair will increase the risk of patella baja, and the use of end-to-end suturing technique alone will not be enough to prevent a rupture recurring; however, augmentation could be used to address the tendon weakness. Repair of the rupture and augmentation with hamstring tendon was performed. One year after the surgery, the patient was able to move his knee joint without pain and had an active range of motion of 0° (passive 20°)-145°. He was able to perform a straight leg raise without an extension lag. CONCLUSIONS: Repair and augmentation with hamstring tendon was an effective treatment option for patellar tendon rupture in a patient with EDS.