A preliminary study on the spasticity reduction of quadriceps after selective dorsal rhizotomy in pediatric cases of spastic cerebral palsy.

OBJECTIVE: This study aimed to evaluate the potential alleviation of quadriceps spasticity in children diagnosed with spastic cerebral palsy (CP) following selective dorsal rhizotomy (SDR). METHODS: A retrospective study was conducted on children suffering from spastic CP who underwent SDR at the Department of Neurosurgery, Shanghai Children's Hospital, from July 2018 to September 2020. Inclusion criteria comprised children exhibiting quadriceps spasticity exceeding modified Ashworth Scale grade 2. Muscle tone and motor function were assessed before the operation, at short-term follow-up and at the last follow-up after SDR. Additionally, intraoperative neurophysiological monitoring data were reviewed. RESULTS: The study comprised 20 eligible cases, where, prior to surgery, 35 quadriceps muscles exhibited spasticity exceeding modified Ashworth Scale grade 2. Following short-term and mid-term follow-up, specifically an average duration of 11 ± 2 days and 1511 ± 210 days after SDR, it was observed that muscle tension in adductors, hamstrings, gastrocnemius, and soleus decreased significantly. This reduction was accompanied by a decrease in quadriceps muscle tone in 24 out of 35 muscles (68.6%). Furthermore, the study found that intraoperative electrophysiological parameters can predict postoperative spasticity relief in the quadriceps. The triggered electromyographic (EMG) output of the transected sensory root/rootlets after single-pulse stimulation revealed that the higher the EMG amplitudes in quadriceps, the greater the likelihood of postoperative decrease in quadriceps muscle tension. CONCLUSIONS: SDR demonstrates the potential to reduce muscle spasticity in lower extremities in children diagnosed with CP, including a notable impact on quadriceps spasticity even they are not targeted in SDR. The utilization of intraoperative neurophysiological monitoring data enhances the predictability of quadriceps spasticity reduction following SDR.

Weaker Quadriceps Muscle Strength With a Quadriceps Tendon Graft Compared With a Patellar or Hamstring Tendon Graft at 7 Months After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Impaired quadriceps muscle strength after anterior cruciate ligament reconstruction (ACLR) is associated with worse clinical outcomes and a risk of reinjuries. Yet, we know little about quadriceps muscle strength in patients reconstructed with a quadriceps tendon (QT) graft, which is increasing in popularity worldwide. PURPOSE: To describe and compare isokinetic quadriceps strength in patients undergoing ACLR with a QT, hamstring tendon (HT), or bone-patellar tendon-bone (BPTB) autograft. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: We included patients with QT grafts (n = 104) and matched them to patients with HT (n = 104) and BPTB (n = 104) grafts based on age, sex, and associated meniscal surgery. Data were collected through clinical strength testing at a mean of 7 ± 1 months postoperatively. Isokinetic strength was measured at 90 deg/s, and quadriceps strength was expressed as the limb symmetry index (LSI) for peak torque, total work, torque at 30° of knee flexion, and time to peak torque. RESULTS: Patients with QT grafts had the most impaired isokinetic quadriceps strength, with the LSI ranging between 67.5% and 75.1%, followed by those with BPTB grafts (74.4%-81.5%) and HT grafts (84.0%-89.0%). Patients with QT grafts had a significantly lower LSI for all variables compared with patients with HT grafts (mean difference: peak torque: -17.4% [95% CI, -21.7 to -13.2], P < .001; total work: -15.9% [95% CI, -20.6 to -11.1], P < .001; torque at 30° of knee flexion: -8.8% [95% CI, -14.7 to -2.9], P = .001; time to peak torque: -17.7% [95% CI, -25.8 to -9.6], P < .001). Compared with patients with BPTB grafts, patients with QT grafts had a significantly lower LSI for all variables (mean difference: peak torque: -6.9% [95% CI, -11.2 to -2.7], P < .001; total work: -7.7% [95% CI, -12.4 to -2.9], P < .001; torque at 30° of knee flexion: -6.3% [95% CI, -12.2 to -0.5], P = .03; time to peak torque: -8.8% [95% CI, -16.9 to -0.7], P = .03). None of the graft groups reached a mean LSI of >90% for peak torque (QT: 67.5% [95% CI, 64.8-70.1]; HT: 84.9% [95% CI, 82.4-87.4]; BPTB: 74.4% [95% CI, 72.0-76.9]). CONCLUSION: At 7 months after ACLR, patients with QT grafts had significantly worse isokinetic quadriceps strength than patients with HT and BPTB grafts. None of the 3 graft groups reached a mean LSI of >90% in quadriceps strength.

Time to treat the tendon rupture induced by surgery: early hypertrophy of the patellar tendon graft site predicts strong quadriceps after ACLR with bone-patellar tendon-bone autograft.

PURPOSE: Quadriceps dysfunction is ubiquitous after anterior cruciate ligament reconstruction, especially when using bone-patellar tendon-bone (BPTB) autografts. The role of patellar tendon hypertrophy after graft harvest on knee extensor strength is unknown. The purpose of this study was to determine the predictive ability of patellar tendon (PT) and quadriceps muscle (Quad) cross-sectional area (CSA) on knee extensor strength 1-2 months after ACLR using BPTB autografts. METHODS: This is a cross-sectional analysis of a cohort 1-2 months after ACLR using BPTB autograft. Peak knee extensor torque, and PT and Quad CSA measured using ultrasound imaging, were collected in 13 males and 14 females. Simple linear regressions compared quadriceps strength index (QI) against limb symmetry index (LSI) in PT and Quad CSA. Multiple linear regressions with sequential model comparisons predicting peak knee extensor torque were performed for each limb. The base model included demographics. Quad CSA was added in the first model, then PT CSA was added in the second model. RESULTS: Both PT (p < 0.001, R2 = 0.693) and Quadriceps CSA (p = 0.013, R2 = 0.223) LSI had a positive linear relationship with QI. In the involved limb, addition of PT CSA significantly improved the model (R2 = 0.781, ΔR2 = 0.211, p for ΔR2 < 0.001). In the uninvolved limb, the addition of Quad CSA improved the model, but the addition of PT CSA did not. CONCLUSION: PT LSI was more predictive of QI than Quad CSA LSI. Involved limb PT CSA mattered more in predicting peak knee extensor torque than did Quad CSA, but in the uninvolved limb, Quad CSA was the most important predictor of peak knee extensor torque. Graft site patellar tendon hypertrophy is key for strong quadriceps early after ACLR. Early targeted loading via exercise to promote healing of the graft site patellar tendon may bring patients a step closer to winning their battle against quadriceps dysfunction. LEVEL OF EVIDENCE: Level I.

Quadriceps injuries.

Injuries to the quadriceps muscle group are common in athletes performing high-speed running and kicking sports. The complex anatomy of the rectus femoris puts it at greatest risk of injury. There is variability in prognosis in the literature, with reinjury rates as high as 67% in the severe graded proximal tear. Studies have highlighted that athletes can reinjure after nonoperative management, and some benefit may be derived from surgical repair to restore function and return to sport (RTS). This injury is potentially career-threatening in the elite-level athlete, and we aim to highlight the key recent literature on interventions to restore strength and function to allow early RTS while reducing the risk of injury recurrence. This article reviews the optimal diagnostic strategies and classification of quadriceps injuries. We highlight the unique anatomy of each injury on MRI and the outcomes of both nonoperative and operative treatment, providing an evidence-based management framework for athletes.

The accessory heads of the quadriceps femoris muscle may affect the layering of the quadriceps tendon and potential graft harvest lengths.

PURPOSE: The aim of the study was to assess the quadriceps femoris system for the presence of additional layers. METHODS: One hundred and twenty-eight lower limbs fixed in 10% formalin were examined. RESULTS: Five types of quadriceps tendon layering were found based on the accessory heads of the quadriceps muscle. Type I (55%)-represented by four heads and four layers, and it was something new because standard orthopaedic textbooks described quadriceps tendon as a structure composed of only three layers. Type II (27.4%)-the first four layers were the same as in Type 1, but the accessory tendon of the fifth head of the quadriceps femoris muscle had the deepest attachments. Type III (10.9%)-this type included 6 heads of quadriceps femoris. It consisted of five layers. Type IV (3.1%)-this type included 7 quadriceps femoris heads. This type consisted of only four layers. Type V (3.1%)-this type included 8 heads of the quadriceps femoris heads. This type consist of 5 layers. CONCLUSION: The findings of this study provide a detailed anatomy of the quadriceps tendon including the accessory tendons of the accessory heads of the quadriceps tendon. The accessory heads of the quadriceps femoris muscle contribute to the layering of the quadriceps tendon. The second conclusion of this study is the development of safe distances depending on the types. Not all types are perfect for harvesting-Type IV seems to be the safest type, in turn Type V the most dangerous.

Better forgotten joint scores when the angle of the prosthetic trochlea is lateral to the quadriceps vector in kinematically aligned total knee arthroplasty.

PURPOSE: The primary aim was to analyze unrestricted kinematic alignment (unKA) total knee arthroplasty (TKA) and determine the frequency of medial deviation of the prosthetic trochlear angle (PTA) of the femoral component relative to the quadriceps vector (QV) that terminates at the anterior inferior iliac spine (AIIS), and whether patients with medial deviation had a worse Forgotten Joint Score (FJS) and Oxford Knee Score (OKS) relative to those with lateral deviation. The secondary aim was to determine the frequency of medial deviation for mechanical alignment (MA) TKA simulations. METHODS: From a database of a single surgeon, the study extracted de-identified data on 147 patients with a CT scanogram showing the pelvis and AIIS, a limb with an unKA TKA, and a native (i.e., healthy) opposite limb. On the scanogram, an examiner, blinded to the PROMs, measured the PTA-QV angle on the unKA TKA and on the opposite limb simulated MA TKA by drawing the PTA at 6° valgus relative to the femoral mechanical axis and measuring the PTA-QV angle. RESULTS: Medial deviation of the PTA occurred in 86% of patients with unKA TKA, and the 126 with medial deviation had a 17/1 point worse median FJS/OKS than the 21 with lateral deviation at a mean follow-up of 47 ± 8 months, respectively (p < 0.0001, p = 0.0053). In addition, 21%, 17%, and 8% of MA TKA had medial deviation after radiographic simulation using reported surgical errors for manual, patient-specific, and robotic instrumentation, respectively. CONCLUSION: In most patients with unKA TKA and a smaller proportion with MA TKA, a PTA of 6° valgus was medial to the QV, which, by excluding the patient's Q-angle, might alter patellofemoral kinematics like an incorrectly oriented trochleoplasty. The 17-point worse FJS in the patients with an unKA TKA and medial deviation of the PTA suggests the surgical target should be to orient the PTA lateral to the QV. LEVEL OF EVIDENCE: IV.

Postoperative quadriceps weakness and male sex are risk factors for patellofemoral articular cartilage lesions after anatomical anterior cruciate ligament reconstruction.

PURPOSE: Patellofemoral (PF) compartment cartilage lesions are a frequent problem after anterior cruciate ligament (ACL) reconstruction. This study aimed to determine the factors that influence PF cartilage lesions after anatomical ACL reconstruction. METHODS: This study enrolled a total of 114 patients who did not manifest PF compartment cartilage lesions during anatomical ACL reconstruction and underwent second-look arthroscopy 18 months postoperatively. Arthroscopy using the International Cartilage Repair Society (ICRS) classification was used to assess cartilage lesions. The correlation between surgical findings, radiographic factors, and clinical factors and change of ICRS grade was analysed. Multivariate regression analysis was conducted to reveal the independent risk factors for PF cartilage lesions among patients' demographic data and parameters that correlated with the change of ICRS grade in the correlation analyses. RESULTS: ICRS grade changes in PF cartilage were significantly correlated with age, sex, quadriceps strength at 1 year postoperatively, hamstrings strength at pre- and 1 year postoperatively, and single leg hop test at 1 year postoperatively. However, no significant correlation was found between the time between injury and surgery, posterior tibial slope angle, pre- and postoperative Tegner activity scale, graft type, initial graft tension, meniscus injury, meniscus injury treatment, pre- and postoperative range of motion, anteroposterior laxity and preoperative quadriceps strength, and the change in ICRS grade. Multivariate regression analysis revealed male (P = 0.019) and quadriceps strength weakness at 1 year postoperatively (P = 0.009) as independent risk factors for PF cartilage lesions. CONCLUSIONS: Quadriceps strength weakness 1 year after ACL reconstruction and males were correlated with a new PF cartilage lesion after anatomical ACL reconstruction, with no significant correlation between bone-patellar tendon-bone autograft, initial graft tension, or extension deficit and new PF cartilage lesion. Rehabilitation that focuses on quadriceps strength after ACL reconstruction is recommended to prevent new PF cartilage lesions. LEVEL OF EVIDENCE: Level IV.

Vitamin D status associates with skeletal muscle loss after anterior cruciate ligament reconstruction.

BACKGROUNDAlthough 25-hydroxyvitamin D [25(OH)D] concentrations of 30 ng/mL or higher are known to reduce injury risk and boost strength, the influence on anterior cruciate ligament reconstruction (ACLR) outcomes remains unexamined. This study aimed to define the vitamin D signaling response to ACLR, assess the relationship between vitamin D status and muscle fiber cross-sectional area (CSA) and bone density outcomes, and discover vitamin D receptor (VDR) targets after ACLR.METHODSTwenty-one young, healthy, physically active participants with recent ACL tears were enrolled (17.8 ± 3.2 years, BMI 26.0 ± 3.5 kg/m2). Data were collected through blood samples, vastus lateralis biopsies, dual energy x-ray bone density measurements, and isokinetic dynamometer measures at baseline, 1 week, 4 months, and 6 months after ACLR. The biopsies facilitated CSA, Western blotting, RNA-seq, and VDR ChIP-seq analyses.RESULTSACLR surgery led to decreased circulating bioactive vitamin D and increased VDR and activating enzyme expression in skeletal muscle 1 week after ACLR. Participants with less than 30 ng/mL 25(OH)D levels (n = 13) displayed more significant quadriceps fiber CSA loss 1 week and 4 months after ACLR than those with 30 ng/mL or higher (n = 8; P < 0.01 for post hoc comparisons; P = 0.041 for time × vitamin D status interaction). RNA-seq and ChIP-seq data integration revealed genes associated with energy metabolism and skeletal muscle recovery, potentially mediating the impact of vitamin D status on ACLR recovery. No difference in bone mineral density losses between groups was observed.CONCLUSIONCorrecting vitamin D status prior to ACLR may aid in preserving skeletal muscle during recovery.FUNDINGNIH grants R01AR072061, R01AR071398-04S1, and K99AR081367.

Limited preoperative knee extension in anterior cruciate ligament reconstruction using a hamstring tendon affects improvement of postoperative knee extensor strength.

PURPOSE: This study aimed to determine the factors affecting knee extensor strength 6 months after anterior cruciate ligament (ACL) reconstruction using autograft hamstring tendon. METHODS: 144 patients who could undergo regular follow-up after ACL reconstruction were divided into 2 groups: those with greater than 90% (Group A: n = 95) and less than 85% (Group B: n = 49) isokinetic knee contraction at 60°/s 6 months post-ACL reconstruction. Basic information, injury status, limited preoperative knee extension, and knee extensor strength at 3 and 6 months postoperatively were compared between the groups. Multivariate logistic analysis was performed and included variables that showed statistically significant differences between the groups in the univariate analysis. In addition, the cut-off value for the limb symmetry index (LSI) at 3 months postoperatively needed to exceed an LSI of 90% at 6 months postoperatively was calculated using the receiver operating characteristics curve. RESULTS: Age, preoperative waiting period, limited preoperative knee extension, and knee extensor strength at 3 months postoperatively were significantly different between the two groups. The multivariate logistic analysis showed that all the variables affected the improvement in knee extensor strength at 6 months postoperatively. Limited preoperative knee extension was the most significant factor (odds ratio: 15.1, 95% confidence interval: 2.57-118.56, p < 0.01). The LSI cut-off value at 3 months postoperatively was 72.0%. CONCLUSION: Key factors in achieving the necessary knee extensor strength criteria for return to sports at 6 months post-ACL reconstruction include addressing limited preoperative knee extension and achieving an LSI ≥ 72% in knee extensor strength at 3 months postoperatively. LEVEL OF EVIDENCE: Level III.

Increased quadriceps muscle strength after medial meniscus posterior root repair is associated with decreased medial meniscus extrusion progression.

BACKGROUND: This study aimed to assess quadriceps muscle strength after medial meniscus (MM) posterior root repair and determine its relationship with clinical scores and MM extrusion (MME). METHODS: Thirty patients who underwent pullout repair for MM posterior root tear and were evaluated for quadriceps muscle strength preoperatively and at 1 year postoperatively were included in this study. Quadriceps muscle strength was measured using the Locomo Scan-II instrument (ALCARE, Tokyo, Japan). MME and clinical scores (i.e., Knee Injury and Osteoarthritis Outcome Score [KOOS], International Knee Documentation Committee score, Lysholm score, Tegner score, and visual analog scale pain score) were evaluated preoperatively and at 1 year postoperatively, and second-look arthroscopy was performed at 1 year postoperatively. Wilcoxon's signed-rank test was used to compare each measure pre- and postoperatively. Pearson's correlation coefficient was used to assess the correlation with quadriceps muscle strength values. Multiple regression analysis was performed to identify factors associated with the change in MME (ΔMME). RESULTS: Second-look arthroscopy confirmed continuity of the posterior root in all patients. The quadriceps muscle strength measured at 1 year postoperatively (355.1 ± 116.2 N) indicated significant improvement relative to the quadriceps muscle strength measured preoperatively (271.9 ± 97.4 N, p < 0.001). The MME at 1 year postoperatively (4.59 ± 1.24 mm) had progressed significantly relative to the MME preoperatively (3.63 ± 1.01 mm, p < 0.001). The clinical scores at 1 year postoperatively were improved significantly relative to the scores preoperatively (p < 0.001). The postoperative quadriceps muscle strength was correlated with ΔMME (correlation coefficient = -0.398, p = 0.030), and the change in quadriceps muscle strength was correlated with the KOOS-Quality of Life (correlation coefficient = 0.430, p = 0.018). Multiple regression analysis showed that the postoperative quadriceps muscle strength had a significant effect on ΔMME even when the body mass index and time from injury to surgery were included. CONCLUSIONS: After MM posterior root repair, patients with greater quadriceps muscle strength showed less MME progression. In addition, patients with greater improvement in quadriceps muscle strength had better clinical scores; therefore, continued rehabilitation aimed at improving quadriceps muscle strength after MM posterior root repair is recommended. LEVEL OF EVIDENCE: IV.

The Influence of Quadriceps Strength and Rate of Torque Development on the Recovery of Knee Biomechanics During Running After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: After anterior cruciate ligament reconstruction (ACLR), altered surgical knee biomechanics during running is common. Although greater quadriceps strength is associated with more symmetrical running knee kinetics after ACLR, abnormal running mechanics persist even after resolution of quadriceps strength deficits. As running is a submaximal effort task characterized by limited time to develop knee extensor torque, quadriceps rate of torque development (RTD) may be more closely associated with recovery of running knee mechanics than peak torque (PT). PURPOSE: To assess the influence of recovery in quadriceps PT and RTD symmetry on knee kinematic and kinetic symmetry during running over the initial 2 years after ACLR. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 39 Division I collegiate athletes (106 testing sessions; 19 female) completed serial isometric performance testing and running analyses between 3 and 24 months after ACLR. Athletes performed maximal and rapid isometric knee extension efforts with each limb to assess PT and RTD between-limb symmetry indices (PTLSI and RTDLSI), respectively. Peak knee flexion difference (PKFDIFF) and peak knee extensor moment limb symmetry index (PKEMLSI) during running were computed. Multivariable linear mixed-effects models assessed the influence of PTLSI and RTDLSI on PKFDIFF and PKEMLSI over the initial 2 years after ACLR. RESULTS: Significant main effects of RTDLSI (P < .001) and time (P≤ .02) but not PTLSI (P≥ .24) were observed for both PKFDIFF and PKEMLSI models. For a 10% increase in RTDLSI, while controlling for PTLSI and time, a 0.9° (95% CI, 0.5°-1.3°) reduction in PKFDIFF and a 3.5% (95% CI, 1.9%-5.1%) increase in PKEMLSI are expected. For every month after ACLR, a 0.2° (95% CI, 0.1°-0.4°) reduction in PKFDIFF and a 1.3% (95% CI, 0.6%-2.0%) increase in PKEMLSI are expected, controlling for PTLSI and RTDLSI. CONCLUSION: Quadriceps RTDLSI was more strongly associated with symmetrical knee biomechanics during running compared with PTLSI or time throughout the first 2 years after ACLR.

Vastus Lateralis and Vastus Intermedius Myocutaneous Flap Reconstruction for Complicated Trochanteric and Ischial Pressure Sores with Extended Girdlestone Resection: A Case Series.

OBJECTIVE: Most paraplegic patients with complicated trochanter sores or ischial sores present with lower limb muscle atrophy. Therefore, in patients who have undergone Girdlestone arthroplasty, filling the dead space and replacing the volume defect through an appropriate surgical technique is extremely challenging. This study presents a case series of vastus lateralis and vastus intermedius myocutaneous flap reconstruction after extended proximal femoral osteotomy in paraplegic patients. The aim of study is to investigate (i) whether sufficient volume replacement was achieved, (ii) whether muscle volume was maintained during long-term follow-up, and (iii) the presence of donor site morbidity. METHOD: A retrospective review was conducted with eight patients who underwent this method from March 2017 to December 2021. A total of nine flaps was elevated, and the defect was successfully reconstructed without dead space. Computed tomography was performed to identify the changes in thickness and volume of the muscle portion. The Wilcoxon signed-rank test was performed to assess the significance of the differences in muscle thickness between pre- and post-measurements. RESULTS: After surgery, all patients healed within 1 month; three patients experienced minor complications. The average follow-up period was 14.5 months, during which only one patient with an ischial pressure ulcer developed wound disruption and recurrence. The average thickness of the rotated muscle was 51.95 mm at 2 to 4 weeks postoperatively and 53.07 mm at 6 months postoperatively (𝑝 = 0.071). CONCLUSION: All nine cases healed well without major complications. When comparing the volume of the rotated muscle on radiological examinations before and after surgery, no significant differences were observed. Our modified Girdlestone resection technique provides a simple and reliable method for reconstructing complex trochanteric or ischial sores in paraplegic patients. It ensures anatomical consistency, ample volume, and structural stability by leaving the rectus femoris (RF) in place. Careful tension management is required when using this flap in the ischial area.

[Effect of dietary supplements and whey protein on muscle mass and strength of the operated limb after anterior cruciate ligament reconstruction: a systematic review].

Muscle weakness and atrophy of the quadriceps muscle after anterior cruciate ligament reconstruction may persist for up to 6 months after surgery and cause re-injury to the ipsilateral or contralateral limbs. Many authors state that adequate nutritional status during the rehabilitation period can contribute to faster postoperative recovery of muscle mass and strength of the lower limb, be an adjunct to exercise, or serve an alternative treatment strategy. The purpose of the research was to conduct a systematic review of the literature and evaluate the degree of influence of dietary supplements on muscle mass and strength of the operated limb after reconstruction of the anterior cruciate ligament (ACL). Material and methods. The search for articles was carried out in international databases PubMed, Google Scholar, Cochrane Library. The time frame of the search was 22 years. To be included in the review, studies had to meet the PICOS criteria: participants were men and women over 18 years of age after ACL reconstruction; intervention - supplementation after and/or before and after ACL reconstruction; comparison - placebo group or no supplementary interventions; results - assessment of the dynamics of changes in muscle mass (cross-sectional area, muscle thickness or size of skeletal muscle fibers) and / or maximum strength (dynamic or isometric) of the operated limb; research design - randomized controlled trials (RCT). The quality of selected RCTs was assessed using the Cochrane Collaboration Risk of Bias (RoB 2) tool. Results. A total of 1397 articles were found after searching in the databases. This systematic review included 6 RCTs with a total number of patients 186. The following dietary supplements were used: leucine - 1 article, glucosam ine - 1 article, creatine - 1 article, vitamins E and C - 2 articles. One study evaluated the effect of whey protein supplementation in combination with neuromuscular electrical stimulation on isometric strength of the operated limb. When comparing the data of 3 groups in the pre- and postoperative periods, there were no statistically significant differences between the groups. When considering the protocols for taking dietary supplements based on creatine, glucosamine, vitamins E and C, none of the studies demonstrated statistically significant improvements in the parameters of maximum strength or muscle hypertrophy of the operated limb in the main groups compared with the control groups. Also, no results have been obtained indicating that these dietary supplements can slow down muscl e atrophy after surgery. In another study that evaluated the effect of leucine supplementation, by the end of the rehabilitation program, the muscle strength of the operated limb tended to increase more in the leucine group than in the placebo group, but without a statistically significant difference. At 10 cm from the patella, the femoral circumference of the operated limb in the leucine group increased more than in the placebo group, and the differences were statistically significant (р=0.009). Two studies were rated as high risk of bias, three as moderate risk, and one as low risk. Conclusion. None of the supplements used had a statistically significant effect on the muscle strength of the operated limb after ACL reconstru ction. In terms of thigh muscle hypertrophy, the only significant improvement was associated with leucine supplementation and an increase in thigh circumference at a distance of 10 cm from the patella.

The Impact of Meniscal Tear Type and Surgical Treatment on Quadriceps Strength: A Study of Adolescent Patients Post Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Treatment of meniscal injuries at the time of anterior cruciate ligament reconstruction (ACLR) can result in restrictions on weightbearing and range of motion in the early rehabilitative phases. What is unknown is the effect of (1) meniscal tear type and location at the time of anterior cruciate ligament injury and (2) meniscal treatment at the time of ACLR on quadriceps strength in adolescents during the late rehabilitative phase. HYPOTHESIS: Meniscal tears involving the root and requiring repair would adversely affect quadriceps strength at 6 to 9 months postoperatively. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients who underwent ACLR at 1 of 2 research sites between 2013 and 2021 were identified. Adolescent participants were included if they were between the ages of 12 and 20 years at the time of assessment and had undergone primary unilateral ACLR in the previous 6 to 9 months. Participants were subgrouped by meniscal tear type (no tear, nonroot tear, root tear) and meniscal treatment at the time of ACLR (no treatment, meniscectomy, meniscal repair), which were confirmed via chart review. Isokinetic strength testing occurred at 60 deg/s, and quadriceps strength and quadriceps strength limb symmetry index were compared between the meniscal tear type and meniscal procedure subgroups using analysis of covariance while controlling for the effects of age, sex, and ACLR graft source. RESULTS: An overall 236 patients were included in this analysis (109 male, 127 female; mean ± SD age, 16.0 ± 1.9 years). There were no significant differences in ACLR limb quadriceps strength based on meniscal tear type (P = .61) or meniscal procedure at the time of ACLR (P = .61), after controlling for age, biological sex, and ACLR graft source. Similarly, quadriceps strength limb symmetry index did not differ by meniscal tear type (P = .38) or meniscal procedure at the time of ACLR (P = .40). CONCLUSION: Meniscal tear type and treatment at the time of ACLR did not affect quadriceps strength or quadriceps strength symmetry in adolescents 6 to 9 months after ACLR.

Editorial Commentary: Limited Preoperative Range of Motion Is Associated With Range of Motion Deficits After Anterior Cruciate Ligament Reconstruction: "If the Knee Is Not Straight, Wait".

Optimal timing of anterior cruciate ligament reconstruction (ACLR) remains under debate. Prolonging time between injury and ACLR risks damaging the meniscus and chondral surface, as well as delays return to play. Early ACLR may be associated with postoperative stiffness or arthrofibrosis. We emphasize that optimal timing for ACLR depends on criterion-based return of knee range of motion and quadriceps strength, not a quantitative temporal period. The length of time is far less important that the quality of prereconstruction care provided. Prereconstruction care includes "prehabilitation," including prone hangs focusing on optimizing knee range of motion, postinjury effusion resolution, and mentally preparing the patient for postoperative expectations. Defining preoperative criteria for proceeding with surgery is crucial to decrease the risk of arthrofibrosis. Some patients meet these criteria within 2 weeks, whereas others linger to 10 weeks. Reduction in arthrofibrosis requiring surgical intervention is multifactorial and not solely dependent on the length of time between injury and intervention.

Combining age, sex, body mass index, sport level, and preoperative quadriceps strength improves the predictive ability of quadriceps strength recovery after anterior cruciate ligament reconstruction.

PURPOSE: This study compared the predictive ability of each independent predictor with that of a combination of predictors for quadriceps strength recovery one year after anterior cruciate ligament (ACL) reconstruction. METHODS: Patients who underwent primary ACL reconstruction using hamstring autografts were enrolled. Quadriceps strength, hamstring strength, and anterior tibial translation were measured, and the limb symmetry index (LSI) of the quadriceps and the hamstrings was calculated preoperatively and one year after surgery. Patients were classified into two groups according to the LSI of the quadriceps strength at one year postoperatively (≥ 80% or < 80%). Multivariate logistic regression analysis identified the independent predictors of quadriceps strength recovery, and the cut-off value was calculated using the receiver operating characteristic curve. A model assessing predictive ability of the combination of independent predictors was created, and the area under the curve (AUC) for each independent predictor was calculated by using the receiver-operating characteristic curves and the DeLong method. RESULTS: Of the 646 patients, 414 (64.1%) had an LSI of at least 80% for quadriceps strength one year after surgery, and 232 patients (35.9%) had an LSI of < 80%. Age, sex, body mass index (BMI), preinjury sport level, and LSI of preoperative quadriceps strength were independently associated with quadriceps strength recovery one year after ACL reconstruction. The cut-off values were age: 22.5 years; sex: female; BMI: 24.3 kg/m2; preinjury sport level: no sport; and LSI of preoperative quadriceps strength: 63.3%. The AUC of the model assessing the predictive ability of the combination of age, sex, BMI, preinjury sport level, and LSI of preoperative quadriceps strength was significantly higher (0.73) than that of similar factors of preoperative quadriceps strength (AUC: 0.63, 0.53, 0.56, 0.61, and 0.68, p < 0.01, respectively). CONCLUSION: The combination of age, sex, BMI, preinjury sport level, and LSI of preoperative quadriceps strength had a superior predictive ability for quadriceps strength recovery at one year after ACL reconstruction than these predictors alone. Multiple factors, including patient characteristics and preoperative quadriceps strength, should be considered when planning rehabilitation programs to improve quadriceps strength recovery after ACL reconstruction. LEVEL OF EVIDENCE: III.

[Return to Sport (RTS) After Anterior Cruciate Ligament Reconstruction: Which Factors Influence the RTS Decision?] / Rückkehr zum Sport nach Rekonstruktion des vorderen Kreuzbandes ­ Welche Faktoren beeinflussen die Return to Sport-Entscheidung?

BACKGROUND: It is unknown which valid criteria should be considered to justify the decision for return to sport (RTS) following anterior cruciate ligament reconstruction (ACLR). The research question is whether gender, age, the outcome of the isokinetic maximal strength measurement and the single-leg hop test (quantitative/qualitative) influence the decision for RTS nine months after ACLR. METHODS: This study is a retrospective data analysis. The research question was evaluated with a multiple logistic regression analysis (MLR). The dependent variable, RTS yes/no, is based on the decision of the orthopaedist in charge of treatment nine months (±30 days) after ACLR. The following possible influencing factors were investigated: gender, age, limb symmetry index (LSI) of maximal knee extension and knee flexion strength at 60°/sec., LSI of single-leg hop test and evaluation of knee valgus. RESULTS: Data of 71 patients were included for MLR. The odds ratios (OR) for RTS increased with female gender (OR, 4.808; p=0.035), a higher LSI of maximal strength of knee extension (OR, 1.117; p=0.009) and a higher LSI of the single-leg hop test (OR, 1.125; p=0.020). Age, the LSI of maximal strength of knee flexion and knee valgus had no influence on the RTS decision. CONCLUSION: Gender and the limb symmetry indexes of the maximal strength of knee extension and of the single-leg hop test are associated with RTS nine months after ACLR. These results should be considered to optimise rehabilitation after ACLR.

Rotura traumática simultánea y bilateral del tendón del cuádriceps en un paciente fisicoculturista: informe de caso y revisión de la literatura / Simultaneous bilateral traumatic quadriceps tendon rupture in a bodybuilding patient: case report and literature review

La rotura traumática, simultánea y bilateral del tendón cuadricipital es una lesión infrecuente, generalmente asociada a otras enfermedades sistémicas tales como insuficiencia renal o trastornos endocrinos. Presentamos el caso de un varón sano y atleta de 38 años que sufrió esta lesión mientras realizaba una sentadilla en el gimnasio. (AU)

The traumatic bilateral and simultaneous quadriceps tendon rupture is a rare injury, usually associated with other systemic diseases such as renal insufficiency or endocrine disorders. We present the case of a 38-year-old healthy male athlete who sustained this injury while performing a squat at the gym. (AU)

Chronic quadriceps tendon rupture: quadriceps tendon reconstruction using ipsilateral semitendinosus tendon graft.

Ruptures of the quadriceps tendon (QTRs) are uncommon. If the rupture is not diagnosed, chronic ruptures may develop. Re-ruptures of the quadriceps tendon are rare. Surgery is challenging because of tendon retraction, atrophy and poor quality of the remaining tissue. Multiple surgical techniques have been described. We propose a novel technique in which the quadriceps tendon is reconstructed using the ipsilateral semitendinosus tendon.