Abstract
Purpose
The purposes of this study were to evaluate reliability of the Single-limb mini squat test (a dynamic measure of medio-lateral knee position) and the Quadriceps-angle (Q-angle) (a static measure of medio-lateral knee position), present paediatric reference values of the Q-angle, and evaluate the association between the tests.
Methods
Two hundred and forty-six healthy children (9–16 years) were included (intra/inter-rater reliability for Q-angle (n = 37/85) and for Single-limb mini squat test (n = 33/28)). Dynamic medio-lateral knee position was assessed by the Single-limb mini squat test. Static medio-lateral knee position was evaluated by the Q-angle.
Results
The reliability of the Single-limb mini squat test was found to be moderate (kappa 0.48–0.57, 95% CI 0.16–0.85, 76–79% agreement). Fair to moderate reliability (ICC 0.35-0.42, 95% CI 0.11–0.66, SEM 1.4°–1.9°, n.s.) of the Q-angle measurements was found. Reference values for the Q-angle (mean 13.5° (1.9)–15.3° (2.8)) varies with age and gender. No associations were found between dynamic and static measures.
Conclusions
The Single-limb mini squat test showed a moderate reliability and the Q-angle showed a fair to moderate reliability. A difference found for age and gender was lower than 5° and may not be clinical significant. No association were found between the two tests, indicating dynamic and static knee position being two different concepts. In a clinical perspective, we suggest that the Single-limb mini squat test is a contribution to the available tool box for evaluation of dynamic medio-lateral knee position in children, although the Q-angle may not be used before more research has been done justifying its use.
Level of evidence
Diagnostic study, Level III.
Similar content being viewed by others
References
Ageberg E, Bennell KL, Hunt MA, Simic M, Roos EM, Creaby MW (2010) Validity and inter-rater reliability of medio-lateral knee motion observed during a single-limb mini squat. BMC Musculoskelet Disord 11:265–272
Andriacchi TP (1994) Dynamics of knee malalignment. Orthop Clin North Am 25:395–403
Barber-Westin SD, Smith ST, Campbell T, Noyes FR (2010) The Drop-jump video screening test: retention of improvement in neuromuscular control in female volleyball players. J Strength Cond Res 24:3055–3062
Bayraktar B, Yucesir I, Ozturk A, Cakmak AK, Taskara N, Kale A, Demiryurek D, Bayramoglu A, Camlica H (2004) Change of quadriceps angle values with age and activity. J Saudi Med 25:756–760
Beyer WH (1966) Handbook of tables for probability and Statistics. The Chemical Ruber CO, Cleveland
Bland JM, Altman DG (1986) Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1:307–310
Bremander AB, Dahl LL, Roos EM (2007) Validity and reliability of functional performance tests in meniscectomized patients with or without knee osteoarthritis. Scand J Med Sci Sports 17:120–127
Duffey MJ, Martin DF, Cannon DW, Craven T, Messier SP (2000) Etiologic factors associated with anterior knee pain in distance runners. Med Sci Sports Exerc 32:1825–1832
Hewett TE, Ford KR, Myer GD (2006) Anterior cruciate ligament injuries in female athletes: part 2, a meta-analysis of neuromuscular interventions aimed at injury prevention. Am J Sports Med 34:490–498
Hunter DJ, Sharma L, Skaife T (2009) Alignment and osteoarthritis of the knee. J Bone Joint Surg Am 91(1):85–89
Insall J, Falvo KA, Wise DW (1976) Chondromalacia Patellae. A prospective study. J Bone Joint Surg Am 58:1–8
Kramer LC, Denegar CR, Buckley WE, Hertel J (2007) Factors associated with anterior cruciate ligament injury: history in female athletes. J Sports Med Phys Fitness 47:446–454
Landis JR, Koch GG (1977) The measurement of observer agreement for categorical data. Biometrics 33:159–174
Livingston LA (1998) The quadriceps angle: a review of the literature. J Orthop Sports Phys Ther 28:105–109
Loudon JK, Jenkins W, Loudon KL (1996) The relationship between static posture and ACL injury in female athletes. J Orthop Sports Phys Ther 24:91–97
Nietosvaara Y, Aalto K, Kallio PE (1994) Acute patellar dislocation in children: incidence and associated osteochondral fractures. J Pediatr Orthop 14:513–515
Noyes FR, Barber-Westin SD, Fleckenstein C, Walsh C, West J (2005) The drop-jump screening test: difference in lower limb control by gender and effect of neuromuscular training in female athletes. Am J Sports Med 33:197–207
Pantano KJ, White SC, Gilchrist LA, Leddy J (2005) Differences in peak knee valgus angles between individuals with high and low Q-angles during a single limb squat. Clin Biomech 20:966–972
Rankin G, Stokes M (1998) Reliability of assessment tools in rehabilitation: an illustration of appropriate statistical analyses. Clin Rehabil 12:187–199
Rauh MJ, Koepsell TD, Rivara FP, Rice SG, Margherita AJ (2007) Quadriceps angle and risk of injury among high school cross-country runners. J Orthop Sports Phys Ther 37:725–733
Roebroeck ME, Harlaar J, Lankhorst GJ (1993) The application of generalizability theory to reliability assessment: an illustration using isometric force measurements. Phys Ther 73:386–395
Shrout PE, Fleiss JL (1979) Intraclass correlations: uses in assessing rater reliability. Psychol Bull 86:420–428
Shultz SJ, Nguyen AD, Schmitz RJ (2008) Differences in lower extremity anatomical and postural characteristics in males and females between maturation groups. J Orthop Sports Phys Ther 38:137–149
Shultz SJ, Nguyen AD, Windley TC, Kulas AS, Botic TL, Beynnon BD (2006) Intratester and intertester reliability of clinical measures of lower extremity anatomic characteristics: implications for multicenter studies. Clin J Sport Med 16:155–161
Sim J, Wright CC (2005) The kappa statistic in reliability studies: use, interpretation, and sample size requirements. Phys Ther 85:257–268
Smith TO, Hunt NJ, Donell ST (2008) The reliability and validity of the Q-angle: a systematic review. Knee Surg Sports Traumatol Arthrosc 16:1068–1079
Tomsich DA, Nitz AJ, Threlkeld AJ, Shapiro R (1996) Patellofemoral alignment: reliability. J Orthop Sports Phys Ther 23:200–208
Woodland LH, Francis RS (1992) Parameters and comparisons of the quadriceps angle of college-aged men and women in the supine and standing positions. Am J Sports Med 20:208–211
Acknowledgments
This study was supported by grants from Promobilia, Trygg-Hansa and Karolinska Institutet. The authors also wish to thank Elisabeth Berg for help with the statistical analysis.
Conflict of interest
The authors declare that they have no conflict of interest.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Örtqvist, M., Moström, E.B., Roos, E.M. et al. Reliability and reference values of two clinical measurements of dynamic and static knee position in healthy children. Knee Surg Sports Traumatol Arthrosc 19, 2060–2066 (2011). https://doi.org/10.1007/s00167-011-1542-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00167-011-1542-9