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Knee Surgery, Sports Traumatology, Arthroscopy

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01-11-2014 | Knee

Introduction of a classification system for patients with patellofemoral instability (WARPS and STAID)

Authors: Laurie A. Hiemstra, Sarah Kerslake, Mark Lafave, S. Mark Heard, Gregory M. L. Buchko

Published in: Knee Surgery, Sports Traumatology, Arthroscopy | Issue 11/2014

Abstract

Purpose

The primary purpose of this paper is to introduce the WARPS/STAID classification system for patellofemoral instability. The secondary purpose is to establish the validity and reliability of the WARPS/STAID classification system.

Methods

Patients (n = 31) with a confirmed diagnosis of patellofemoral instability underwent a thorough knee history and physical examination with 3 raters. The raters graded each component of the WARPS/STAID classification system on a visual analogue scale (VAS). A single Global VAS WARPS/STAID score was graded after all other components of the classification system were completed. Intraclass correlation coefficient (ICC 2, 3) was calculated for each metric of the classification scale and for the Global score. Concurrent validity was assessed by correlating the WARPS/STAID score with the Kujala score. Subjects were assigned to one of three categories (WARPS, STAID, or mixed characteristics) according to the Total WARPS/STAID score to determine the level of agreement between the three raters.

Results

Intraclass correlation coefficient (ICC 2, 3) of the WARPS/STAID classification continuum ranged between 0.73 and 0.91 for the individual metrics of the classification. The ICC (2, 3) for the Global WARPS/STAID score was 0.75. The mean Kujala score (m = 61, SD 18) was significantly correlated with the total WARPS/STAID score (r = 0.387, p < 0.05). The majority of subjects were assigned to either the WARPS or STAID categories.

Conclusion

This study introduced the WARPS/STAID classification system and established both validity and reliability in subjects with patellofemoral instability.

Level of evidence

II.

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Andrish J (2007) Surgical options for patellar stabilization in the skeletally immature patient. Sports Med Arthrosc 15(2):82–88PubMedCrossRef

Arendt EA, Fithian DC, Cohen E (2002) Current concepts of lateral patella dislocation. Clin Sports Med 21(3):499–519PubMedCrossRef

Atkin DM, Fithian DC, Marangi KS, Stone ML, Dobson BE, Mendelsohn C (2000) Characteristics of patients with primary acute lateral patellar dislocation and their recovery within the first 6 months of injury. Am J Sports Med 28(4):472–479PubMed

Balcarek P, Ammon J, Frosch S, Walde TA, Schuttrumpf JP, Ferlemann KG, Lill H, Sturmer KM, Frosch KH (2010) Magnetic resonance imaging characteristics of the medial patellofemoral ligament lesion in acute lateral patellar dislocations considering trochlear dysplasia, patella alta, and tibial tuberosity-trochlear groove distance. Arthroscopy 26(7):926–935PubMedCrossRef

Bonett DG (2002) Sample size requirements for testing and estimating coefficient alpha. J Educ Behav Stat 27(4):335–340CrossRef

Camp CL, Krych AJ, Dahm DL, Levy BA, Stuart MJ (2010) Medial patellofemoral ligament repair for recurrent patellar dislocation. Am J Sports Med 38(11):2248–2254PubMedCrossRef

Dejour H, Walch G, Nove-Josserand L, Guier C (1994) Factors of patellar instability: an anatomic radiographic study. Knee Surg Sports Traumatol Arthrosc 2(1):19–26PubMedCrossRef

Franzone JM, Stein BES, Vitale MA, Ahmad CS (2012) Is there an association between chronicity of patellar instability and patellofemoral cartilage lesions? an arthroscopic assessment of chondral injury. J Knee Surg 25(5):411–416PubMedCrossRef

Fulkerson JP, Shea KP (1990) Disorders of patellofemoral alignment. J Bone Joint Surg 72(A)(9):1424–1429

10.

Kujala UM, Jaakkola LH, Koskinen SK, Taimela S, Hurme M, Nelimarkka O (1993) Scoring of patellofemoral disorders. Arthroscopy 9(2):159–163PubMedCrossRef

11.

McFarland EG, Kim TK, Park HB, Neira CA, Gutierrez MI (2003) The effect of variation in definition on the diagnosis of multidirectional instability of the shoulder. J Bone Joint Surg 85-A(11):2138–2144PubMed

12.

McGraw KOWSP (1996) Forming inferences about some intraclass correlation coefficients. Psychol Meth 1:30–46CrossRef

13.

Nomura E, Inoue M (2005) Second-look arthroscopy of cartilage changes of the patellofemoral joint, especially the patella, following acute and recurrent patellar dislocation. Osteoarthr Cartil 13(11):1029–1036PubMedCrossRef

14.

Panni AS, Cerciello S, Maffulli N, Di Cesare M, Servien E, Neyret P (2011) Patellar shape can be a predisposing factor in patellar instability. Knee Surg Sports Traumatol Arthrosc 19(4):663–670PubMedCrossRef

15.

Paxton EW, Fithian DC, Stone ML, Silva P (2003) The reliability and validity of knee-specific and general health instruments in assessing acute patellar dislocation outcomes. Am J Sports Med 31(4):487–492PubMed

16.

Portney LG, Watkins MP (2009) Foundations of clinical research, 3rd edn. Applications to Practice, Prentice Hall

17.

Servien E, Verdonk PC, Neyret P (2007) Tibial tuberosity transfer for episodic patellar dislocation. Sports Med Arthrosc 15(2):61–67PubMedCrossRef

18.

Shrout PE, Fleiss JL (1979) Intraclass correlations: uses in assessing rater reliability. Psychol Bull 86(2):420–428PubMedCrossRef

19.

Sillanpaa P, Mattila VM, Iivonen T, Visuri T, Pihlajamaki H (2008) Incidence and risk factors of acute traumatic primary patellar dislocation. Med Sci Sport Exerc 40(4):606–611CrossRef

20.

Stefancin JJ, Parker RD (2007) First-time traumatic patellar dislocation: a systematic review. Clin Orthop Relat Res 455:93–101PubMedCrossRef

21.

Streiner DL, Norman GR (2003) Health measurement scales: a practical guide to their development and use, 3rd edn. Oxford University Press, New York

22.

Thomas SC, Matsen FA 3rd (1989) An approach to the repair of avulsion of the glenohumeral ligaments in the management of traumatic anterior glenohumeral instability. J Bone Joint Surg 71(4):506–513PubMed

23.

Vollnberg B, Koehlitz T, Jung T, Scheffler S, Hoburg A, Khandker D, Hamm B, Wiener E, Diederichs G (2012) Prevalence of cartilage lesions and early osteoarthritis in patients with patellar dislocation. Eur Radiol 22(11):2347–2356PubMedCrossRef

Title: Introduction of a classification system for patients with patellofemoral instability (WARPS and STAID)
Authors: Laurie A. Hiemstra
Sarah Kerslake
Mark Lafave
S. Mark Heard
Gregory M. L. Buchko
Publication date: 01-11-2014
Publisher: Springer Berlin Heidelberg
Published in: Knee Surgery, Sports Traumatology, Arthroscopy / Issue 11/2014
Print ISSN: 0942-2056
Electronic ISSN: 1433-7347
DOI: https://doi.org/10.1007/s00167-013-2477-0

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Springer Medicine

Introduction of a classification system for patients with patellofemoral instability (WARPS and STAID)

Abstract

Purpose

Methods

Results

Conclusion

Level of evidence

At a glance: The ONWARDS insulin icodec trials

Springer Medicine

Abstract

Purpose

Methods

Results

Conclusion

Level of evidence

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