Factors influencing inconsistent leg length discrepancy in dysplastic hip osteoarthritis: a retrospective study.

BACKGROUND: We aimed to examine the inconsistency between radiographic leg length discrepancy (R-LLD) and perceived LLD (P-LLD) in patients with dysplastic hip osteoarthritis and to evaluate the factors that can cause such inconsistency. METHODS: We conducted a retrospective study on 120 patients. An inconsistent LLD was defined as a condition in which the P-LLD was shorter than the R-LLD by > 5 mm. We compared relevant data on the general characteristics of the patients and the radiological findings between consistent (group E, 92 cases [76.7%]) and inconsistent LLDs (group S, 28 cases [23.3%]). RESULTS: The number of patients with a history of hip surgery on the affected side and the Japanese Orthopedic Association classification pain scores were significantly higher in group S than in group E (32.1% vs. 10.8%, respectively; P = 0.015, and 21.7 ± 7.0 vs. 17.5 ± 8.2, respectively; P = 0.036). The pelvic oblique angle and length of the R-LLD were significantly higher in group S than in group E (2.9 ± 2.5° vs. 0.3 ± 2.3°, respectively; P < 0.01, and 17.2 ± 8.9 mm vs. 6.3 ± 8.4 mm, respectively; P < 0.01). Multivariate logistic analysis revealed that the pelvic oblique angle (odds ratio [OR]: 1.80, 95% confidence interval [CI]: 1.28-2.52; P < 0.01) and length of the R-LLD (OR: 2.75, 95% CI: 1.24-6.12; P = 0.013) were independent risk factors of inconsistent LLD. CONCLUSION: The pelvic oblique angle and a long R-LLD were independent risk factors of inconsistent LLD in patients with dysplastic hip osteoarthritis. Therefore, hip surgeons should consider P-LLD rather than R-LLD to understand the need for conservative intervention.

A preliminary examination of the association between locomotive syndrome and circulating miRNA-199 in community-dwelling people: The Yakumo study.

BACKGROUND: The risk of locomotive syndrome (LS) has been proposed as a criterion for evaluating physical ability. The expression levels of circulating miRNAs (c-miRNAs) are predictors of various diseases. This preliminary study aimed to evaluate the relationship between serum levels of several miRNAs and LS. METHODS: We enrolled 423 participants in whom we conducted a survey with the 25-question Geriatric Locomotive Function Scale (GLFS-25) and measured the serum levels of 21 c-miRNAs. The relationship between the GLFS-25 and each c-miRNA was evaluated with a linear regression analysis, and independent associations between the GLFS-25 and each c-miRNA were assessed with a multiple regression analysis using various independent variables. RESULTS: Only the serum level of miR-199 was significantly associated with LS after adjustment for age, BMI, sex, and all comorbidities. The receiver operating characteristics curve for the predictive value of the miR-199 level to indicate the presence or absence of LS risk had an area under the curve (AUC) of 0.576 (95% confidence interval: 0.501-0.651). CONCLUSION: The expression level of miRNA-199 was associated with the risk of LS in community-dwelling Japanese people.

The development of knee osteoarthritis and serum carotenoid levels among community-dwelling people in Japan.

OBJECTIVES: Carotenoids are plant pigments found in many vegetables, functioning as antioxidants scavenging singlet molecular oxygen and peroxyl radicals. No longitudinal study exists on the relationship between carotenoids and knee osteoarthritis (KOA) development. We aimed to determine the incidence of KOA development for 10 years in community-dwelling people in Japan and assess its association with serum carotenoids. METHODS: Data of 440 participants (174 men, 266 women) with health-screening records for at least 10 years were analysed. We defined KOA development as advancing from K/L grade 0/1 at the initial check-up to grade ≥2 in a unilateral knee during a 10-year follow-up period. Serum carotenoid levels were measured using high-performance liquid chromatography. We used the Cox hazard model for multivariate analysis and investigated each carotenoid's impact on KOA development. RESULTS: KOA developed in 33.4% of patients; the annual KOA development rate was significantly higher among women than among men (p < .01; 3.4% vs. 1.6%). Among the carotenoids measured, only retinol was associated with KOA development in women using multivariable analysis. KOA development was not associated with any carotenoids in men. CONCLUSION: The annual rate of KOA development was higher in women, and retinol was associated with KOA development in women.

Differences of 2-year longitudinal changes of locomotive syndrome among patients treated with thoracolumbar interbody fusion, total hip arthroplasty, and total knee arthroplasty for degenerative diseases.

OBJECTIVES: To clarify the longitudinal changes in patients with preoperative Stage-3 locomotive syndrome (LS) according to different types of surgeries, we investigated the changes in the LS stage in patients who underwent surgery for degenerative musculoskeletal diseases. METHODS: A prospective cohort study was conducted on 168 patients with degenerative diseases [46 spinal deformities treated with thoracolumbar interbody fusion (T/LIF), 86 hips with osteoarthritis treated with total hip arthroplasty (THA), and 36 knees with osteoarthritis treated with total knee arthroplasty (TKA)]. The results for the LS stage, stand-up test, two-step test, and 25-question Geriatric Locomotive Function Scale (GLFS-25) were evaluated preoperatively and at 6 months, 1 year, and 2 years postoperatively. RESULTS: Preoperatively, most patients had Stage-3 LS (89.1, 90.8, and 80.6% in the T/LIF, THA, and TKA groups, respectively). At 2 years postoperatively, the Stage-3 LS improved in 41.5, 75.6, and 55.2% of patients in the T/LIF, THA, and TKA groups, respectively. All groups showed similar improvements in the two-step test. The THA group showed the best result in the GLFS-25. CONCLUSIONS: LS stage improved in different patterns over 2 years postoperatively and the LS risk test revealed differences in postoperative movement ability according to the type of surgery.

Collapse Progression or Cessation Affects the Natural History of Contralateral Osteonecrosis of the Femoral Head.

BACKGROUND: It is unclear how the condition of one side of the hip joint affects the natural history of contralateral osteonecrosis of the femoral head (ONFH). This study aimed to investigate the natural progression of bilateral ONFH on the asymptomatic side between patients with collapse progression and cessation on the symptomatic side. METHODS: The study included 109 patients with bilateral ONFH at the first visit, who were divided into two groups in accordance with the symptomatic side based on the collapse progression of ≥3 mm (progressive group: 74 hips) and collapse cessation of <3 mm (stable group: 35 hips) with a minimum follow-up of 3 years. The assessment parameters included age, gender, body mass index, etiology, type classification, and survival rates of the asymptomatic side with radiographic failure as the endpoints. RESULTS: Age, gender, body mass index, and etiology were not different between the two groups; however, a difference was observed in the type classification of the symptomatic side. The 4-year survival rates were significantly different between the progressive (34.3%) and stable groups (85.7%). Multivariate Cox regression analysis showed that age <40 years (vs ≥40 years; hazard ratio [HR], 2.439), type C2 (vs B + C1; HR, 2.865), and collapse progression on the symptomatic side (vs collapse cessation; HR, 7.751) were independent factors determining collapse on the asymptomatic side. CONCLUSION: Collapse progression on the symptomatic side is a poor prognostic factor for the natural history of contralateral ONFH.

Improvement of locomotive syndrome after total hip arthroplasty: A two-year longitudinal cohort study.

OBJECTIVES: Patients requiring total hip arthroplasty (THA) may possibly have locomotive syndrome (LS). Therefore, we investigated changes of LS in patients undergoing THA and clarified key factors that affected LS stage. METHODS: A prospective cohort study was conducted with 88 patients undergoing THA (74 females, 14 males, mean age: 67.6 years). Data collected using LS stage, stand-up test, two-step test, and 25-question Geriatric Locomotive Function Scale results were evaluated before THA, and 6 months, 1 year, and 2 years after THA. Key factors were determined using multivariate analysis and receiver operating characteristic (ROC) curve analysis. RESULTS: Before THA, all patients had fallen LS (stage1: 3.4% and stage2: 96.6%). Overall, 56.8% patients improved their LS stage, and 17.0% of patients overcame LS at 2 years after THA. The key factors that affected LS stage were preoperative two-step test and age. ROC analyses showed a preoperative two-step test score of 0.988 and an age of 67.5 years as a cut-off value for the change of LS stage. CONCLUSIONS: Patients experiencing LS due to hip disorders have the potential to recover after THA. Additional postoperative training may be beneficial for patients with low preoperative two-step test scores to improve their LS stage.

Stretch reflex changes in ACL-deficient individuals and healthy controls during normal and surprise landings.

No studies in ACL-D individuals have examined neuromuscular adaptations during landing from a jump where an unexpected mechanical event changes the pre-programmed course of movement. The purpose of this study was to compare pre- and post-landing muscle activation in ACL-D individuals and uninjured controls during normal and surprise landings. Nineteen ACL-D and 17 uninjured volunteered. Participants performed repeated single leg landings from 30 and 15 cm heights. During 15 cm landings, a single surprise landing was performed where participants unexpectedly fell through a false surface at 15 cm to the solid floor a further 15 cm below. Electromyography (EMG) amplitude from vastus lateralis (VL), lateral hamstrings (LH), and soleus (Sol) was recorded. Pre-landing (-60 to 0 ms), post-landing short latency (31-60 ms), and post-landing medium latency (61-90 ms) periods were examined. Comparisons in EMG amplitudes were made across limbs (ACL-D, ACL intact, and control) in 30 cm landings. Additionally, the ratio of EMG amplitude in surprise:30 cm normal landings was analyzed. Post-landing LH EMG was reduced in the ACL-D compared to control limbs at short latencies (P < 0.05). Post-landing VL EMG was reduced in the ACL-D and ACL intact compared to the control limb at both latencies (P < 0.05). Surprise landings notably increased post-landing EMG in all muscles, across all limbs (P < 0.001). However, the gain in VL EMG was significantly greater in ACL-D and ACL intact limbs (P < 0.05). These changes in neuromuscular control of ACL-D individuals during expected and surprise landings may have important implications for rehabilitation, instability, and the risk of secondary injury.

Effect of Subcutaneous Tissue on Changes in Thigh Circumference Following Anterior Cruciate Ligament Reconstruction.

Circumference measurements have been used to estimate muscle cross-sectional area (CSA) in clinical settings. Measurements of thigh circumference are affected by muscle and subcutaneous fat (SF). In fact, SF could increase over a short period. Therefore, clarifying the relationship between thigh circumference and muscle and SF following ACL reconstruction is important. This study's primary purpose was to examine pre- and post-operative changes in thigh circumference, thigh muscles and SF CSAs in both legs. Secondary, the relationship between thigh circumference and muscle and SF CSAs was examined to demonstrate that circumference measurements could be used to detect atrophy. Quadriceps, hamstrings, and SF CSAs at 15, 10, and 5 cm proximal to the patella were measured by MRI pre- and 4 weeks postoperatively to examine how reconstruction affected those tissues in the thighs. The results showed increases in SF CSA (r=0.72 at 10 cm, r=0.67 at 15 cm) greatly affected thigh circumference in females on the surgical side. In males, increases in SF CSA (r=0.83) at 15- and 5-cm and decreases in quadriceps muscle CSA (r=0.73) at 5 cm affected thigh circumference on the surgical side. Thigh circumference measurements might not reflect actual muscle CSA in ACL patients.

Muscle Damage After Total Hip Arthroplasty Through the Direct Anterior Approach for Developmental Dysplasia of the Hip.

BACKGROUND: Total hip arthroplasty (THA) through the direct anterior approach (DAA) is known to cause less muscle damage than other surgical approaches. However, more complex primary cases, such as developmental dysplasia of the hip (DDH), might often cause muscle damage. The objective of the present study was to clarify the muscle damage observed 1 year after THA through the DAA for DDH using magnetic resonance imaging. METHODS: We prospectively compared the muscle cross-sectional area (M-CSA) and fatty atrophy (FA) in muscles by magnetic resonance imaging and the Harris hip score before and at 1-year follow-up after THA through the DAA in 3 groups: 37 patients with Crowe group 1 DDH (D1), 13 patients with Crowe group 2 and 3 DDH (D2 + 3), and 12 patients with osteonecrosis as a control. RESULTS: THA through the DAA for D1 displayed significantly decreased M-CSA and significantly increased FA in the gluteus minimus (Gmini), the tensor fasciae latae (TFL), and the obturator internus (OI). Patients with D2 + 3 group did not have decreased M-CSA in the TFL or increased FA in the Gmini. Postoperatively, a significant negative correlation was observed between the M-CSA and FA for the OI in patients with D1 and D2 + 3. CONCLUSION: THA through the DAA for DDH caused the damage in the Gmini, the TFL, and the OI; severe damage was observed in the OI, showing increased FA with decreased M-CSA in patients with both D1 and D2 + 3.

Arthroscopic treatment of symptomatic discoid meniscus in children.

PURPOSE: To study discoid meniscus in children who underwent arthroscopic surgery at our center. SUBJECTS AND METHODS: Thirty-four patients (39 knees) younger than 15 years with discoid lateral meniscus (mean age, 12.9 years; 13 males, 21 females) who underwent arthroscopic surgeries since 2007 were studied. The surgical procedure consisted of, in principle, saucerization with additional suture repair in the case of meniscal instability at the peripheral rim of the residual meniscus. The mechanisms of symptom onset, symptoms, complications and postoperative outcome in these cases were examined. In addition, Lysholm scores were obtained before surgery and at the last postoperative follow-up in all patients. RESULTS: Symptom onset was associated with sports in 18 knees, fall in 3 knees, and no definitive trigger in the remaining knees. The presenting symptoms were pain in 32 knees, catching in 11 knees, and locking in 6 knees. According to Watanabe classification, 26 knees were complete type and 13 knees were incomplete type. The modes of tear included horizontal tear in 10 knees and longitudinal tear in 10 knees, while no definitive tear was present on the knee joint surface. The surgical procedures included saucerization only in 22 knees, partial meniscectomy in 10 knees, and saucerization with suture repair in 5 knees. The mean Lysholm score was 63.9 before surgery, and improved significantly to 92.3 at the last follow-up. Only two knees developed osteochondritis dissecans after surgery. Two knees required reoperation; one knee underwent subtotal meniscectomy and one knee had partial meniscectomy with suturing. CONCLUSION: Although the short-term outcome after saucerization with or without suture repair for discoid meniscus is favorable, degenerative change or change of lower limb alignment may occur in the long term. Further long-term study is required.

Prospective analysis using a patient-based health-related scale shows lower functional scores after posterior cruciate ligament reconstructions as compared with anterior cruciate ligament reconstructions of the knee.

PURPOSE: This study evaluated the treatment outcome of posterior cruciate ligament (PCL) reconstruction using the Medical Outcome Study 36-item Short-Form Health Survey (SF-36), a patient-based quality of life (QOL) questionnaire comparing it with anterior cruciate ligament (ACL) reconstruction. METHODS: Patients who underwent reconstruction at our center for PCL (n = 24) or ACL (n = 197) injury were studied. The patients were evaluated using SF-36, visual analogue scale (VAS) for knee pain, Lysholm scale, posterior or anterior tibial translation and range of motion (ROM) before surgery until 24 months after surgery. Results were compared. RESULTS: In the ACL group, all evaluation methods showed significant improvement after surgery. In the PCL group, however, improvement was observed in only three of eight subscales of the SF-36, Lysholm score and posterior tibial translation after surgery. In intergroup comparison, the PCL group showed inferior performance in three subscales of the SF-36, Lysholm score and ROM for flexion compared with the ACL group. CONCLUSIONS: The surgical outcome of PCL reconstruction was inferior to that of ACL reconstruction both in patient-based and conventional doctor-based assessments. An improved surgical technique for PCL is required.

Meniscal tears associated with anterior cruciate ligament injury.

PURPOSE: To investigate the frequency of meniscal tear and the location of tear associated with anterior cruciate ligament (ACL) injury. SUBJECTS AND METHODS: We studied 549 patients (552 knees) who were diagnosed with ACL injury by arthroscopy at our center between January 2006 and March 2014 (8 years and 3 months). The subjects comprised 289 males and 263 females ranging in age from 13 to 66 (mean 26.1) years. The cause of injury was sports-related in 89.1 %, and the mean interval from injury to initial arthroscopy was 23 months. The patients were divided into two groups: arthroscopy performed within 8 weeks after injury (acute group; 256 knees) and more than 8 weeks after injury (chronic group; 296 knees). Frequency of meniscal tear and location of tear were compared between two groups. RESULTS: The incidence of meniscal tear diagnosed by arthroscopic examination was 79.2 % (437 of 552 knees) in all subjects; 72.7 % (186 of 256 knees) in acute group and 84.8 % (251 of 296 knees) in chronic group, and was significantly higher in chronic group. Regarding the locations of meniscal tears, in acute group (186 knees), medial meniscal tear only was found in 20 knees (10.8 %), lateral meniscal tear only in 129 knees (69.4 %), and bilateral (including medial and lateral) meniscal tears in 37 knees (19.9 %). In chronic group (251 knees), medial meniscal tear only was found in 62 knees (24.7 %), lateral meniscal tear only in 85 knees (33.9 %), and bilateral meniscal tears in 104 knees (41.4 %). Lateral meniscal tear was commonly associated with acute ACL injury, while medial meniscal tear with chronic ACL injury. Bucket handle tear was observed in 25 knees (medial: 17 knees, lateral: 8 knees) in acute group, and 81 knees (medial: 69 knees, lateral: 12 knees) in chronic group, and was more common in the chronic group. CONCLUSION: The incidence of meniscal tear associated with ACL injury is higher in chronic cases; the number of medial meniscal tears is particularly high, many of which require meniscectomy. Early ACL reconstruction is recommended also for the prevention of secondary meniscal tear.

Stabilization of photochromic isomers by copper nanoparticles in a high-diffusivity solid matrix.

Nanoparticles that are dispersed in a solid matrix have no effect on co-dispersed molecules unless they happen to be located close to one another. A polymer with a high diffusion coefficient allows molecules to circulate in the matrix to find a particle that enhances their function. A polymer composite containing copper nanoparticles was created by a low-temperature, nonvacuum process. That is, laser ablation was conducted in polydimethylsiloxane oil for both anti-oxidation and efficient particle collection, and then this suspension was cured to create a metal-polymer composite. This composite enhanced optical functions of a photochromic dye owing to its high diffusivity.

Prospective evaluation of patients with anterior cruciate ligament reconstruction using a patient-based health-related survey: comparison of acute and chronic cases.

INTRODUCTION: To verify the usefulness of and optimal timing for conducting anterior cruciate ligament (ACL) reconstruction, we evaluated and compared baseline characteristics and surgical outcomes in patients with ACL injury divided into acute and chronic groups. PATIENTS AND METHODS: 101 patients after ACL reconstruction were studied. Patients who underwent surgery within 8 weeks after injury were classified as acute group (n = 40), and those having surgery after 8 weeks as chronic group (n = 61). SF-36, VAS, Lysholm score, anterior tibial translation, and pivot shift were assessed before surgery and 6, 18 and 30 months after surgery. The results of two groups were compared. RESULTS: In the preoperative SF-36 survey, physical and mental health scores were lower than the national standard scores in both groups. Physical health score was significantly lower in acute group, although mental health score was not significantly different between two groups. Preoperative VAS and Lysholm score were significantly poorer in acute group compared to chronic group. However, preoperative anterior tibial translation and pivot shift were not significantly different between the two groups. In postoperative evaluations, all parameters were improved significantly compared to preoperative values in both groups, and no significant differences were observed between the two groups. DISCUSSION: All evaluation methods showed significant improvements after surgery in both acute and chronic groups, confirming that ACL reconstruction is useful for both acute and chronic injuries. However, preoperative evaluations by SF-36, VAS, and Lysholm scale yielded different results in two groups, indicating the need to evaluate acute and chronic cases separately. Development of a specific evaluation method that is valid for any duration from injury to surgery is desirable.

Complications after arthroscopic knee surgery.

PURPOSE: To examine the complications of arthroscopic knee surgeries conducted in the Sports Medicine and Knee Center of our hospital. SUBJECTS AND METHODS: In this prospective study, a total of 2,623 patients (1,396 men and 1,227 women) who underwent arthroscopic knee surgeries in our center between January 2006 and March 2013 (7 years and 3 months) were studied. The ages at surgery ranged 7-96 years (mean 33.5 years). Arthroscopy was conducted because of sports injuries in 1,653 patients (63.0 %). The main diagnoses included meniscal injury in 920 patients, discoid meniscus in 64 patients, anterior cruciate ligament injury in 580 knees, posterior cruciate ligament injury in 30 knees, loose body in 61 knees, and intraarticular fracture in 33 knees. Arthroscopic procedures included meniscectomy in 987 knees, meniscal suture repair in 262 knees, and anterior cruciate ligament reconstruction in 508 knees. Intraoperative and postoperative complications in these cases were investigated. RESULTS: The rate of complication was 7 in 2,623 cases (0.27 %). Intraoperative complications comprised three cases of intraarticular instrument breakage and one case of meniscal injury. Postoperative complications consisted of two cases of septic arthritis and one case of superficial infection, and reoperation was necessary in the two cases of septic arthritis. There were no neural, vascular and ligament injuries during surgery, and no complex regional pain syndrome, symptomatic deep vein thrombosis, and pulmonary embolism were observed. CONCLUSION: Arthroscopic knee surgeries are considered to be minimally invasive, and are conducted relatively safe with low complication rates. In this series, however, seven cases of complications occurred, including two cases (0.08 %) of septic arthritis. Furthermore, symptomatic thromboembolism has been reported to occur also in arthroscopic surgery. The risk of severe complications has to be acknowledged.

Clinical results of arthroscopic all-inside lateral meniscal repair using the Meniscal Viper Repair System.

PURPOSE: This study examined the postoperative outcome of the all-inside arthroscopic meniscal suture repair technique using the Meniscal Viper Repair System for lateral meniscus tears. METHODS: Between January 2006 and December 2008, 57 patients (27 males and 30 females) with lateral meniscus tears who underwent meniscal repair using the Meniscal Viper Repair System were evaluated prospectively. Among them, 52 cases were tears involving the posterior third of the lateral meniscus, and most were longitudinal tears or bucket handle tears. The postoperative follow-up period ranged from 12 months to 4 years and 2 months, and averaged 19 months. RESULTS: Both Lysholm and Japanese Orthopaedic Association Score were significantly improved after surgery. Forty-nine of 57 patients (86.0 %) had no locking or catching, no joint line tenderness, and a negative McMurray test at the last follow-up. Of 32 patients who underwent second-look arthroscopy, 24 achieved complete healing, while four showed partial healing and required repeat repair, and four showed no healing and meniscectomy was conducted. The failure rate in all patients was thus 14.0 % (8 of 57 repairs). No major complications associated with the use of the Meniscal Viper Repair System were observed. CONCLUSION: The Meniscal Viper System is a convenient and effective device for all- inside lateral meniscal suture, with high success rate and no major complications.

Impacts of Segond Fractures on Anterior Cruciate Ligament Reconstruction Outcomes.

INTRODUCTION: Segond fractures, characterized by avulsion injuries at the lateral tibial condyle's anterolateral structure (ALS) attachment, often coincide with anterior cruciate ligament (ACL) injuries, potentially leading to knee instability. However, the influence of Segond fractures on knee stability after ACL reconstruction remains uncertain. Despite documented ALS reconstructions, there is a lack of consensus regarding the assessment of ALS failure and the criteria for surgical interventions. This study aimed to determine if Segond fracture presence impacts ACL reconstruction outcomes, utilizing patient-reported subjective assessments and healthcare providers' objective evaluations. MATERIALS AND METHODS: This retrospective study encompassed 639 patients (328 males, 311 females; mean age 26.9 years) who underwent ACL reconstruction, with a follow-up of at least one year. Subjects were divided into two groups: Segond fractures diagnosed through radiographic findings (Group S+, n = 17) and no Segond fractures (Group S-, n = 622). Clinical evaluation included the 36-item Short Form Survey (SF-36), Lysholm score, visual analog scale (VAS) for knee pain, knee injury and osteoarthritis outcome score (KOOS), and knee instability assessment via Telos SE (Telos Japan, Tokyo, Japan). Statistical comparisons were performed between the two groups. RESULTS: At the final follow-up, all SF-36 subscales improved in all eight subscales compared to before surgery, reaching national standard scores; no significant inter-group differences were evident. Lysholm scores were 93.0 ± 12.1 (Group S+) and 91.7 ± 10.9 (Group S-) (P = 0.62), VAS for knee pain was 10.0 ± 18.0 (Group S+) and 11.9 ± 16.9 (Group S-) (P = 0.62), total KOOS was 89.0 ± 17.4 (Group S+) and 90.7 ± 9.9 (Group S-) (P = 0.39), and anterior tibial translation differences were 2.8 ± 3.0 mm (Group S+) and 2.7 ± 2.9 mm (Group S-) (P = 0.73). All these values represent postoperative measurements. No significant discrepancies existed between groups across evaluation methods. CONCLUSIONS: This study's results suggest that Segond fractures have minimal impact on clinical ACL reconstruction outcomes, as assessed through both patient-reported subjective evaluations and objective healthcare provider evaluations. Segond fractures' significance in postoperative outcomes questions the necessity of ALS reconstruction.

Abnormality in re-programing of preparatory muscle activity for landing following unpredictable events in patients with anterior cruciate ligament injury.

BACKGROUND: Anterior cruciate ligament deficiency (ACL-D) causes dysfunction in the quadriceps femoris muscle, and this dysfunction hampers a safe return to sports. However, how the dysfunctional quadriceps femoris muscle affects instantaneous re-programming of motor command in response to unpredictable events remains unknown. This study aimed to examine the effects of ACL-D on re-programming of preparatory muscle activity during an unpredictable landing task. METHODS: Eighteen patients with ACL-D and 20 healthy participants (controls) performed normal landing and surprise landing tasks. In the surprise landing task, a false floor, designed to dislodge easily under load, was positioned in the middle of the descent path. This setup causes participants to unpredictably fall through the false floor onto the actual landing surface. Electromyography data collected during the period after passing through the false floor until landing was segmented into two equal halves. The average electromyography amplitude for each muscle in each period was compared between patients and controls. RESULTS: In the vastus medialis and rectus femoris during the surprise landing task, the average electromyography amplitude during only the second half period in patients with ACL-D was significantly smaller than that in controls (p = 0.011 and 0.004, respectively). CONCLUSIONS: Abnormalities were detected in the re-programming of preparatory muscle activation during an unpredictable landing task in the vastus medialis and rectus femoris of patients with ACL-D. The surprise landing task used in the present study has the potential to become a diagnostic tool to evaluate readiness for safely returning to sports.

Hereditary Anatomical Risk Factors for Anterior Cruciate Ligament Injuries.

INTRODUCTION:  Genetic and anatomical factors have been reported as risk factors for anterior cruciate ligament (ACL) injuries. This study aimed to investigate anatomical characteristics in family members sustaining ACL injuries, compared with age- and sex-matched patients with simple meniscus injuries. MATERIALS AND METHODS:  Medical records of 1548 patients who underwent ACL reconstruction were reviewed. Cases of ACL injury occurring in first-degree relatives were selected. Forty-one patients from 20 families were included in the study (F-ACL group). Fifty patients with meniscus injuries were included as controls. Anatomical factors comprising posterior-inferior tibial slope (PITS), notch width index (NWI), notch angle (NA), and intercondylar notch roof inclination angle (RA) were compared between groups. The correlation of these anatomical factors between parent and child or siblings was also investigated. RESULTS:  The 41 patients (20 families) consisted of 12 parent-child pairs and 29 siblings (13 pairs and one trio). Injuries occurred during playing the same sport in 11 families (55%). PITS was significantly steeper in the F-ACL group (9.9 vs. 7.8 degrees). NWI and NA were significantly smaller in the F-ACL group (0.262 vs. 0.278 and 50.5 vs. 58.8 degrees). RA was significantly greater in the F-ACL group (130 vs. 126.9 degrees). A positive correlation in NA (r = 0.677) and a weak correlation in NWI and RA were observed between family members. CONCLUSIONS:  Common anatomical risk factors of ACL injury exist within families, including intercondylar notch stenosis and steep posterior tibial slope. The findings suggest the potential for developing effective ACL injury prevention programs targeting these risk factors.