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Introduction: Evaluating the mechanical-anatomical alignment and angles of the knee joint is crucial for athletes. We aimed to analyse the relationship between lower extremity bone alignment and the importance of the Q angle (QA) in male athletes., Methods: We included 38 male professional football athletes without any alignment or varus-valgus deformity who actively played football in various football clubs in Istanbul. This study was conducted using quantitative research methods within the scope of a cohort study design and employed a correlational survey method. A health specialist at the orthopaedic outpatient clinic of the Haseki Training and Research Hospital, Istanbul, evaluated the participants' lower extremity bone alignment using standing anteroposterior radiographs and assessed the QA using the goniometric measurement method. The anatomical lateral distal femoral angle (aLDFA), medial proximal tibial angle (MPTA) and QA data were analysed to assess lower extremity straightness., Results: Significant relationships between the right and left leg aLDFA, MPTA and QA values of the participants' lower extremity mechanical axis values and between the aLDFA and right leg QA values ( r  = 0.380, p  = 0.019) were found. These relationships were attributed to the difference between proximal and distal alignments of the lower extremities. The correlation between QA and certain mechanical alignment parameters was due to unilateral and bilateral symmetrical arrangements of the lower extremities., Conclusions: The parameters of lower extremity mechanical-anatomical alignment are considered preliminary indicators of relationships among sports injuries, structural factors and predisposition to such injuries. Individual differences in the angular values of mechanical-anatomical alignment and the application of different methods for determining these angles have revealed some uncertainties. We determined the mechanical axis data of football athletes who predominantly used their lower extremities using the most reliable methods and examined the relationship among the right and left leg aLDFA, MPTA and QA values. We believe that our findings provide insights and guidance for experts in the field., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Patellofemoral or anterior knee pain is a common cause of medical evaluation around the globe. It affects one in four individuals and is more frequent in females. It is considered a multifactorial disease in which conservative management must focus on the alterations found in the physical exam and radiologic images. Recurrence is high, as 39-40% of the patients continue with symptoms in one year of follow-up. Surgical management should be considered when symptoms persist after six months of conservative measures and when evident malalignments are identified. This article aims to establish and summarize the possible causes, involve the importance of the physical examination and the radiologic images suggested, as to consider the different treatment options that may be used to treat such a frequent and irregular pathology., Competing Interests: The authors declare no conflict of interest

Background: The newly defined angle, quadriceps-patella angle (QPA), reflects the combined force transmitted to the patella by the quadriceps muscles and patellar tendon. An increase in QPA may correlate with an increased force on the patella, which is significant in diagnosing patellofemoral instability and pain syndrome. In our study, we examined how various angles and pathologies vary depending on lateral patellar tilt angle (LPTA). QPA and patellar malalignment was investigated. Thus, the importance of understanding patellar malalignment and the research gap., Methods: Three hundred and fifty patients who underwent knee magnetic resonance imaging (MRI) examinations were included. The cross-sectional study conducted retrospectively between the years of 2018-2020 in a tertiary care outpatient clinic. Shapiro-Wilk normality, Chi-square, Mann-Whitney- U , Spearman correlation and receiver operating characteristic (ROC) curve analysis, statistical tests used for analysis. The patellar tendon length, patellar height, tibial tubercle-trochlear groove distance (TT-TG), patella angle, trochlear sulcus angle, trochlear groove depth (TGD), medial trochlea length (MT), lateral trochlea length (LT), medial trochlear/lateral trochlear length ratio (MT/LT), LPTA, patella-patellar tendon angle (PPTA), QPA, Insall-Salvati index (ISI), medial trochlear inclination (MTI), lateral trochlear inclination (LTI) were among these measurements. In addition, we aim to reveal whether there is a significant relationship between two important angles LPTA and QPA. Whether there is a significant increase in the development of chondromalacia for the patient group with LPTA >5°. We examined how the frequency of chondromalacia changes in the patient group with LPTA >5°., Results: Two hundred and seventy seven patients included in the study and many measurements were performed on MRI. Fad-pad edema was found to be significantly higher in the group with LPTA <5° (P=0.046). TT-TG distance was significantly higher, TGD and MT were significantly lower in patients with higher LPTA (P=0.001, P=0.002 and P=0.017, respectively). A low level of significant positive correlation was found between QPA and patellar tendon length. There is no significant difference between QPA and PPTA angles between the groups with LPTA <5° and >5° (P=0.503, P=0.188). In the ROC analysis performed to determine the cut-off value, the LPTA value ≤14.2° which significantly predicted the presence of fad-pad edema, had the highest sensitivity and specificity [sensitivity: 76.71%, specificity: 39.90%, area under the curve (AUC): 0.588, P=0.024]., Conclusions: QPA is independent from many angles of the knee and does not change significantly. As the patellar tendon length increases, QPA angle also increases. In patients with abnormal LPTA, the frequency of TT-TG distance and chondromalacia increased, while TGD and MT decreased. Patients with a low LPTA can be more carefully examined for chondromalacia and fad-pad edema in clinical and MRI examination., Competing Interests: Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-23-1592/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

Anterior Cruciate Ligament (ACL) injuries are a prevalent concern in athletic population, particularly among female athletes who are disproportionately affected. The increased incidence of ACL injuries in females is attributed to a combination of anatomical, physiological, and biomechanical factors that influence knee stability. This review comprehensively explores these contributing factors, highlighting gender-specific anatomical differences such as wider pelvis, increased quadriceps (Q) angle, and steeper tibial slopes, all of which predispose females to greater knee valgus during dynamic activities. Furthermore, hormonal influences and greater ligament laxity are discussed as physiological contributors to increased ACL injury risk. Biomechanical factors such as reduced knee flexion, increased knee valgus, and altered muscle activation patterns further amplify the risk of ACL tears in female athletes. Despite extensive research, gaps remain in the understanding of how these factors interact and influence injury susceptibility. This article is focussed on the critical points in the current literature, analyzing key risk factors, and identifying future research directions that can inform more effective prevention strategies. A better understanding of these factors will ultimately contribute to reducing the incidence of ACL injuries among female athletes and improving long-term strength and stability of knee joint., Competing Interests: Competing interests: All authors have read the manuscript and declare no conflict of interest. No writing assistance was utilized in the production of this manuscript.

Introduction Gonarthrosis (G) is a progressive disease that affects the knee joint and causes pain and limitation of movement in the knee. The determination of the morphometric status of G patients has been a subject of interest recently. The purpose of this study is to determine how hamstring length (HL) and patellofemoral angle (Q angle [QA]) affect the ability of individuals with G to maintain balance. Methods A total of 80 (40 G patients and 40 in the control group [CG]) participants aged 40-65 were included in the study. A goniometer was used to measure the participants' QA. The mean age of the participants was 50.18±7.16 in the G group and 51.40±6.64 in CG. HL was measured using the sit-and-reach test. Participants' dynamic balance state was evaluated using the Y balance test by stepping in the following directions: right-anterior (R-An), right-posteromedial (R-Pm), right-posterolateral (R-Pl), left-anterior (L-An), left-posteromedial (L-Pm), and left-posterolateral (L-Pl). Results According to the results of this research, the balance performance of G patients was significantly lower in all directions (R-An, R-Pm, R-Pl, L-An, L-Pm, L-Pl) compared to the CG. In both groups, R-QA, L-QA, and HL did not change. However, linear regression analysis indicated that in G patients, R-QA, L-QA, and HL affected balance performance. No significant interaction was found between these parameters and balance performance in the CG. Conclusion HL and QA have a significant role in determining body balance. In our study, we found that QA decreased in G patients, leading to genu varum in these individuals. The hamstring muscle shortening observed in G patients significantly negatively affected balance, especially in the R-An, R-Pm, L-An, L-Pm, and L-Pl directions. For healthcare professionals preparing treatment protocols for G patients, we recommend providing exercises to improve balance, especially in these directions., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Ciftci et al.)

Background: Football practice involves a great muscular demand, leading to the development of the lower limbs that, on occasions, can cause deviations from the normal anthropometric values. The quadriceps angle (Q angle) is a value often taken as a reference for the alignment of the lower limbs., Objective: To observe the changes of the Q angle in young football players, because of muscular effort, analyzing the differences between four groups of different ages and to determine whether the playing position might influence these variations., Methods: A cross sectional study was carried out with 104 male subjects divided into four groups according to age: under 8 years-old, 8-17 years-old, 17-21 years-old and over 21 years-old. A photograph was taken in standing position and the Q angle was plotted with KINOVEA® software. As for the reliability of the measurements, intraclass intra and interobserver coefficient were 0.958 and 0.860 respectively. The study was conducted in mid-season., Results: Q angle value is greater in those under 8 years of age and decreases gradually and significantly (p < 0.005) until 17-21 years of age, where it stabilizes at values of 5.73° ± 2.78 for right Q angle and 5.88° ± 2.55 for left Q angle. Two way ANOVA demonstrated a significant group*position interaction for goalkeepers with a medium effect size in both angles (p < 0.001) with a medium effect (η 2 Right Q angle = 0.31; η 2 Left Q angle = 0.37). The values remain unchanged in subjects over 21 years of age (p > 0.005), except for goalkeepers, who suffered a difference in the evolution of the angle within their age category (p < 0.005) and with a high effect size with the other positions (value > 0.8) except forward (value < 0.5)., Conclusion: This study determines that the Q angle in football players decreases with growth, reaching values below 15° at the end of development. Playing positions only influence players over the age of 21, and the Q-angle of goalkeepers is greater than that of other players., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (© 2023 The Authors.)

Background: The aim of this study was to compare the effect of exercises focusing on the proximal and distal joints to knee and knee local exercises on the Patellar location in athletes with patellofemoral pain (PFP)., Methods: A randomized controlled, single-blinded trial was conducted. Thirty-five athletes with PFP were randomly divided into three groups; proximal (12), distal (11) and local (12). Q Angle was measured with goniometer, tilt and congruence angle were measured with digital radiology before and after the exercise programs. The exercises were performed three sessions of 70 min per week, for 8 weeks. Data were analyzed by mixed analysis of variance, post hoc test and dependent t-test., Results: In the pre-intervention, no significant difference was observed between the groups (P > 0.05). But in the post-intervention, Q angle, tilt angle, congruence angle and knee pain in the proximal group were significantly less than the distal and local groups (P < 0.01); while there were no significant differences between the distal and local groups (P > 0.05). Also, in the proximal group, there were significant differences between pre-intervention and post intervention in Q angle, tilt angle and congruence angle (P = 0.001), but no significant differences were observed in the distal and local groups (P > 0.05). Knee pain in all three groups showed significant differences between pre-intervention and post-intervention (P < 0.01)., Conclusions: The findings of the present study indicated further improvement in patellar location and knee pain in the proximal group. Accordingly, proximal group exercises can improve the pain and performance of athletes with PFP by patellar relocation to the normal position., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background and Objectives: Anterior cruciate ligament (ACL) injuries occur as a result of the deterioration of the static and dynamic stability of the knee. One of the structures involved in providing static stability is the patellofemoral angle (Q angle). The aim of this study was to investigate the relationships between Q angle, pelvis diameter, lower extremity length, and foot posture index (FPI) in patients who had undergone ACL reconstruction (ACLR) with the semitendinosus/gracilis (ST/G) technique on both the operated and non-operated sides. Materials and Methods: Twenty-five male recreational athletic patients between the ages of 18 and 35 who had undergone semitendinosus/gracilis (ST/G) anterior cruciate ligament reconstruction at least 6 months earlier were included in the study. Femur length, lower extremity length, pelvis diameter, and Q angle measurements, total foot posture index (FPI) scores, and single leg hop (SLH) and triple hop distance (THD) test results were determined on the operated and non-operated sides. Results: When the findings of the patients were evaluated statistically between the operated and non-operated sides, no significant differences were found in Q angle, femur length, and lower extremity length ( p > 0.05). In terms of FPI scores, a significant difference was found only in the inversion/eversion of the calcaneus (CALC) parameter ( p < 0.05). When the single hop test (SLHT) results were evaluated statistically on the operated and non-operated sides, the results were in favor of the non-operated side ( p < 0.05). In the correlation analysis conducted for both the operated and non-operated sides, positive and significant correlations were found only between SLH and THD ( p < 0.05). No significant difference was found in the other parameters. Conclusions : The fact that ST/G ACLR 6th month post-operative findings revealed similar results in Q angle, lower extremity length, and total FPI scores between the operated and non-operated sides showed that the 6-month process did not cause a difference in these parameters. However, it was found that the operated sides showed lower findings compared to non-operated sides for SLHTs, although these findings were within normal ranges in terms of the limb symmetry index.

Background: Anterior knee pain is the most common problem in the young and sporting population. Quadriceps femoris angle and condylar distance are tools to assess the bio-mechanical function of the knee joint. The aim of this research was to give comparative data of quadriceps femoris angle and condylar distance in the Indian population (sedentary/sportsperson). The study also aims to know which parameter (condylar distance/quadriceps angle) is the better predictor for knee pain in the young Indian population., Materials and Methods: This study was composed of a total of 130 individuals suffering from anterior knee pain which was divided into two categories; Sedentary and sportsperson. Each category consisted of 65 individuals. Q angle (goniometric method) and condylar distance (manual caliper) of each participant were calculated. A comparison of body parameters was done by independent t-test. Comparison between the two parameters (condylar distance and quadriceps angle) was done to know which is the better predictor of anterior knee pain., Results: Statistically significant sexual variation (p<0.05) was observed in both quadriceps angle and condylar distance in sedentary and sportsperson groups. Females had a higher value of Q angle than males (p<0.05). The difference in quadriceps angle was statistically significant (p<0.05) between sedentary and sportsperson groups. Cohen's kappa coefficient of Q angle was 0.72 while that of bi-condylar distance was 0.49.  Conclusion: Q angle is a better indicator for anterior knee pain than condylar distance. Females in either category; sedentary and sportsperson, had higher Q angle in comparison to males making them more susceptible to disorders of the patellofemoral joint. Hence, encouragement and awareness are needed not only to carry out periodic screening of the susceptible population but also to emphasize its usage in clinical practice and the prognosis of the affected individual after treatment., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Chaudhary et al.)

Background: Studies have shown that Q angle measurements were unreliable. Imaging studies have largely replaced the Q angle for measuring tibial tubercle lateralization. Creating a standardized protocol to measure the Q angle, with normative values, would provide a reliable reference without expensive imaging techniques., Methods: Thirty men and 27 women without history of knee problems or family history of dislocating kneecaps were subjects. Exclusion criteria were: patellofemoral abnormalities upon examination. We measured the Q angles of both knees using a standardized protocol and a long-armed goniometer. These data were analyzed to calculate normative values., Results: For all subjects, the mean was 14.8° (≈15°), 95% confidence interval (CI): ±5.4°. The male mean was 13.5°, 95% CI: ±5.2°. The female mean was 15.9°, 95% CI: ±4.8°. There was no significant difference between the right and left knees of the males (p = 0.52), nor of the females (p = 0.62), Beta = 0.14. The 2.4° difference between male and female means was due to the average height difference between the men and women., Conclusions: This study provides a standardized Q angle measurement protocol to assess tibial tubercle lateralization at a patient's first encounter (and intra-operatively) without resorting to expensive imaging studies. These values provide a reliable reference for clinical comparison, and will allow all clinicians and sports medicine personnel to assess tubercle lateralization with reliability and validity. When using this protocol, the term "Standard Q Angle" (SQA) should be used, to avoid confusion with other measurement protocols., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Introduction: The high rate of recurrence in patellar dislocation treatment, requires a more comprehensive action, this is due to causes not only single but often multifactorial, including problems with static stability, dynamic stability or both., Presentation of Case: 1 st case: A-39-years-old male, complain of irreducible right patella dislocation with valgus knee and already done soft tissue procedure for patella dislocation. Long-leg radiographs of the right leg showed 18° valgus mechanical angle. 2 nd case: A-26-years-old obese female, complain of dislocation of left patella and history of surgery for dislocation at 5 years old. Long-leg radiographs of the right leg showed 11° valgus mechanical angle., Discussion: After knowing the cause of the patellar dislocation from history taking, physical and supporting examination, we performed lateral open wedge distal femoral osteotomy also MPFL and MCL reconstruction, and tibial tuberosity medialization osteotomy. There is improvement mean score in Tegner Lysholm Knee Scoring system and IKDC Scoring at 6 months after surgery., Conclusion: Lateral open wedge distal femur osteotomy combine with MPFL and MCL reconstruction and tibial tuberosity medialization realignment procedure can be successfully done for improve irreducible patellar dislocation in valgus knee, from clinical and radiological evaluation have good outcome after surgery., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Changes in postural stability may be a reason for injuries in individuals who have altered musculoskeletal alignment. Q angle (QA) has shown to be a predictor for lower extremity injuries. However, the relationship between balance and QA has not been investigated in young adults., Objective: The aim of the study was to investigate the relationship between QA and balance in young adults., Methods: Ninety participants performed the single leg stance test (SLST) and Star Excursion Balance Test (SEBT) to assess static and dynamic balance, respectively. QA was measured using a manual goniometer. Participants were divided into low, normal and high QA groups., Results: The relationship between SLST and QA was not statistically significant in both eyes opened and closed condition (r=-0.030, p= 0.782; r= 0.031, p= 0.774; respectively). SLST scores did not differ among the three groups in both eyes opened and closed condition (p= 0.781, p= 0.790; respectively). QA significantly correlated with lateral, posterolateral directions and sum score of SEBT (r= 0.240, p= 0.023; r= 0.269, p= 0.010; r= 0.210, p= 0.047). The comparisons among the low, normal and high Q angle groups' SEBT scores showed that balance performance in lateral direction was poorer in low QA group (p= 0.027)., Conclusions: The results of the study showed that QA and dynamic balance have a significant relationship. To reduce musculoskeletal injury risk, the dynamic balance should be assessed in young adults who have lower QA.

This aim of this study is to observe the differences in foot posture and the angle of the knee according to different physical activities. Seventy-eight football players and 72 swimmers were recruited, and in each case a foot posture analysis, based on the foot posture index (FPI), was conducted and the Q angle of the knee was determined. The following mean values were obtained for the lower extremities: in the swimmers, FPI 6.45 ± 2.04 and Q angle 15.38º ± 3.79º. In the footballers, FPI 2.23 ± 1.72 and Q angle 13.16º ± 1.36º. There were statistically significant differences (p < 0.001) between the two groups. The swimmers presented a foot posture with a tendency towards pronation, and a Q angle with a tendency towards valgus, while the results for the footballers were within the normal range.

Purpose: An increased lateral quadriceps vector has been associated with lateral patellar dislocation. Surgical correction of this increased vector through tibial tubercle medialization is often recommended when the quadriceps vector is "excessive". This can be evaluated by physical examination measurements of Q-angle and/or tubercle sulcus angle (TSA), as well as the magnetic resonance imaging (MRI) measurement of tibial tubercle-trochlear groove (TT-TG) distance. This study examined the relationship between three objective measurements of lateral quadriceps vector (TT-TG, Q-angle, TSA). A secondary goal was to relate lateral patellar tilt to these measurements., Methods: Consecutive patients undergoing patellofemoral stabilization surgery from 9/2010 to 6/2011 were included. The Q-angle and TSA were measured on intra-operative physical examination. The TT-TG and patellar tilt were measured on MRI. TSA, Q-angle, and patellar tilt were compared to TT-TG using Pearson correlation coefficient., Results: The study cohort included 49 patients, ages 12-37 (mean 23.2); 62% female. The Pearson correlation coefficients showed (+) significance (p < 0.01) between the TT-TG and both TSA and Q-angle. Tilt and TT-TG were (+) non-significantly correlated. Despite positive correlations of each measurement with TT-TG, there is not uniform intra-patient correlation. In other words, if TT-TG is elevated for a patient, it does not guarantee that all other measurements, including tilt, are elevated in that individual patient., Conclusion: The TT-TG distance has significant positive correlation with the measurements of TSA and Q-angle in patients undergoing surgery for patellofemoral instability. The clinical relevance is that the variability within individual patients demonstrates the need for considering both TSA and TT-TG before and during surgical intervention to avoid overcorrection with a medial tibial tubercle osteotomy., Level of Evidence: Diagnostic study, Level III.

Objectives: This study aims to investigate the effects of knee and foot alignments on the risk of falling., Patients and Methods: Between April 2016 and December 2016, a total of 74 individuals (24 males, 50 females; mean age 32.2±4.9 years; range 18 to 65 years) were included in the study. The knee Q angle and Chippaux-Smirak Index (CSI), Arch Index, and foot progression angle (FPA) evaluated by pedobarography were used for the assessment of the lower extremity alignment. The fall risk was evaluated by the Fall Index, Fourier 56 Index (F56), and Stability Index., Results: The fall index was found to be correlated with the Q angle, CSI, the Arch index, and FPA (p<0.05). Q angle, Arch Index, and FPA which were explained 40% of the variance of the fall index. The Q angle was correlated with F56 and the stability index at the most position (p<0.05). The CSI was correlated with the F56 and the stability index at two and three positions, respectively (p<0.05); however, the Arch Index and FPA were not correlated with the F56 and Stability Index at any of the eight positions (p>0.05). According to the categorical regression analysis, the Q angle was the most effective on the F56 and Stability Index., Conclusion: Our study results suggest that lower extremity malalignment increases the risk of falling. We believe that the risk of falling can be decreased by the reduction of these malalingments and, thus, mortality and morbidity associated with the fall can be reduced as well., Competing Interests: Conflict of Interest: The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Purpose: To determine whether the tibial tuberosity-to-trochlear groove distance (TT-TG) and patellar tendon-to-trochlear groove distance (PT-TG) are equal, whether the bony and cartilaginous points coincide in the trochlea, and whether the insertion of the PT coincides with the most anterior point of the TT in patients with patellar instability., Methods: Fifty-three MRI scans of patients with patellar instability were examined. TT-TG and PT-TG were measured by three examiners in 31 knees. Additionally, the bone-cartilage distance in the trochlea [trochlear cartilage to trochlear bone (TC-TB)] and the distance between the mid-point of the PT insertion and the most anterior point of the TT (PT-TT) were measured by one examiner. The intraclass correlation coefficient was used to evaluate the reliability of the measurements between the three examiners. The relationships between the measurements were determined, the means of the measurements were calculated, and the correlations between PT-TG and TT-TG, PT-TT, and TC-TB were assessed., Results: The ICC was above 0.8. PT-TG was 3.7 mm greater than TT-TG. The TC and TB coincided in 73 % of cases, and the mean TC-TB was 0.3 mm. The PT was lateral to the TT in 94 % of the cases, and the mean PT-TT was 3.4 mm. The Pearson's correlation coefficients between PT-TG and TT-TG, PT-TT, and TC-TB were 0.946, 0.679, and 0.199, respectively., Conclusion: TT-TG underestimated PT-TG, primarily due to the lateralization of the PT insertion relative to the most anterior point of the TT., Clinical Relevance: our study shows that in patients with patellar instability, there are differences in the absolute values of TT-TG and PT-TG, as previously reported for patients without patellar instability. Hence, normal cut-off values based on case-control studies of TT-TG cannot be equivalently used when measuring PT-TG to indicate TT medialization in patients with patellar instability. It is also important to note that the clinical outcomes cannot be directly compared between patients evaluated using TT-TG versus PT-TG measurements., Level of Evidence: III.

Examination of the patellofemoral joint can prove to be challenging. Although certain acute injuries such as patella fracture or tendon rupture can be diagnosed quickly, more chronic injuries such as patellar subluxation and patellofemoral pain syndrome are more difficult to diagnose because of the subtlety of the examination findings. The source of the problem can also vary, and must be identified to direct treatment. Adding to the complexity is that other structures around the knee may present with anterior knee pain and can be mistaken for patellofemoral disorder, which is why the patellofemoral examination should be performed in the context of a complete knee examination. For all of these reasons, performing a thorough and systematic examination of the patellofemoral joint can lead to optimal outcomes for patients., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: The relationship between one-leg static standing balance (OLSSB) and patellofemoral pain syndrome (PFPS) is unknown., Hypothesis: OLSSB decreases in patients with PFPS., Design: Prospective case series., Methods: Fifty-two women with unilateral PFPS were enrolled in this study. OLSSB was evaluated with a stabilometer. Q angle was measured with a lengthened-arm universal goniometer. Lower extremity alignment was analyzed with full-length standing anteroposterior teleroentgenograms. Quadriceps and hamstring strength was measured on an isokinetic dynamometer., Results: There were significant differences in OLSSB, Q angle, and strength of quadriceps and hamstring between the symptomatic and asymptomatic sides. There was a correlation between the strength of the quadriceps and hamstring and OLSSB, while there was no correlation between OLSSB and the severity of pain, lower extremity alignment, and Q angle on the symptomatic side., Conclusions: OLSSB and quadriceps and hamstring strength decreased and Q angle increased on the symptomatic side in PFPS patients. A relationship between OLSSB and pain, Q angle, and lower extremity alignment was not detected, while there was a correlation between the strength of the quadriceps and hamstring and OLSSB., Clinical Relevance: A quadriceps and hamstring strengthening may be beneficial to improve OLSSB in patients with PFPS.

Objectives: The objective of this study was to document and explain bilateral differences in the Q angle., Materials and Methods: Two hundred limbs of healthy adult Indian volunteers were studied. The Q angle was measured using a goniometric method with the subjects supine, quadriceps relaxed and lower limbs in neutral rotation. The relative lateral placement of the tibial tuberosity with respect to the centre of the patella was measured. Appropriate statistical tests were used to determine the bilateral variability in the Q angle and the lateral placement of the tibial tuberosity. Inter-observer variation of the above mentioned parameters were studied in twenty limbs., Results: The average Q angle value of all the 200 limbs was 12.73 °C; the mean value on the right was 12.86 °C and 12.60 °C on the left. When the Q angle and the lateral placement of the tibial tuberosity were considered in pairs a significant difference was noted in males. The Q angle value on the right side was more often greater than the left. The relative lateral placement of the tibial tuberosity showed a significant positive correlation with the Q angle. The intra-class correlation coefficient was 0.66 for the Q angle and 0.8 for the lateral placement of the tibial tuberosity., Conclusion: The present study shows that bilateral variability in the Q angle could be attributed to an alteration of the relative placement of the tibial tuberosity with respect to the centre of the patella.