Abstract
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.
Similar content being viewed by others
References
Amis AA (2007) Current concepts on anatomy and biomechanics of patellar stability. Sports Med Arthrosc 15:48–56
Arendt EA, Dejour D (2013) Patella instability: building bridges across the ocean a historic review. Knee Surg Sports Traumatol Arthrosc 21:279–293
Balcarek P, Jung K, Frosch KH, Sturmer KM (2011) Value of the tibial tuberosity-trochlear groove distance in patellar instability in the young athlete. Am J Sports Med 39:1756–1761
Balcarek P, Walde TA, Frosch S, Schuttrumpf JP, Wachowski MM, Sturmer KM, Frosch KH (2011) Patellar dislocations in children, adolescents and adults: a comparative MRI study of medial patellofemoral ligament injury patterns and trochlear groove anatomy. Eur J Radiol 79:415–420
Beaconsfield T, Pintore E, Maffulli N, Petri GJ (1994) Radiological measurements in patellofemoral disorders. A review. Clin Orthop Relat Res 308:18–28
Biyani R, Elias JJ, Saranathan A, Feng H, Guseila LM, Morscher MA, Jones KC (2014) Anatomical factors influencing patellar tracking in the unstable patellofemoral joint. Knee Surg Sports Traumatol Arthrosc 22:2334–2341
Brown DE, Alexander AH, Lichtman DM (1984) The Elmslie-Trillat procedure: evaluation in patellar dislocation and subluxation. Am J Sports Med 12:104–109
Camp CL, Heidenreich MJ, Dahm DL, Stuart MJ, Levy BA, Krych AJ (2016) Individualizing the tibial tubercle-trochlear groove distance: patellar instability ratios that predict recurrent instability. Am J Sports Med 44:393–399
Camp CL, Stuart MJ, Krych AJ, Levy BA, Bond JR, Collins MS, Dahm DL (2013) CT and MRI measurements of tibial tubercle-trochlear groove distances are not equivalent in patients with patellar instability. Am J Sports Med 41:1835–1840
Cooke TD, Price N, Fisher B, Hedden D (1990) The inwardly pointing knee. An unrecognized problem of external rotational malalignment. Clin Orthop Relat Res 260:56–60
Daynes J, Hinckel BB, Farr J (2015) Tibial tuberosity-posterior cruciate ligament distance. J Knee Surg. doi:10.1055/s-0035-1564732
Dejour D, Le Coultre B (2007) Osteotomies in patello-femoral instabilities. Sports Med Arthrosc 15:39–46
Dejour H, Walch G, Nove-Josserand L, Guier C (1994) Factors of patellar instability: an anatomic radiographic study. Knee Surg Sports Traumatol Arthrosc 2:19–26
Farr J, Covell DJ, Lattermann C (2012) Cartilage lesions in patellofemoral dislocations: incidents/locations/when to treat. Sports Med Arthrosc 20:181–186
Fithian DC, Paxton EW, Stone ML, Silva P, Davis DK, Elias DA, White LM (2004) Epidemiology and natural history of acute patellar dislocation. Am J Sports Med 32:1114–1121
Fulkerson JP (1983) Anteromedialization of the tibial tuberosity for patellofemoral malalignment. Clin Orthop Relat Res 177:176–181
Guerrero P, Li X, Patel K, Brown M, Busconi B (2009) Medial patellofemoral ligament injury patterns and associated pathology in lateral patella dislocation: an MRI study. BMC Sports Med Arthrosc Rehabil Ther Technol 1:17
Hawkins RJ, Bell RH, Anisette G (1986) Acute patellar dislocations. The natural history. Am J Sports Med 14:117–120
Heidenreich MJ, Camp CL, Dahm DL, Stuart MJ, Levy BA, Krych AJ (2015) The contribution of the tibial tubercle to patellar instability: analysis of tibial tubercle-trochlear groove (TT-TG) and tibial tubercle-posterior cruciate ligament (TT-PCL) distances. Knee Surg Sports Traumatol Arthrosc. doi:10.1007/s00167-015-3715-4
Hinckel BB, Gobbi RG, Filho EN, Pecora JR, Camanho GL, Rodrigues MB, Demange MK (2015) Are the osseous and tendinous-cartilaginous tibial tuberosity-trochlear groove distances the same on CT and MRI? Skeletal Radiol 44:1085–1093
Hinckel BB, Gobbi RG, Kihara Filho EN, Demange MK, Pécora JR, Camanho GL (2015) Patellar tendon–trochlear groove angle measurement: a new method for patellofemoral rotational analyses. Orthop J Sports Med 3:2325967115601031
Ho CP, James EW, Surowiec RK, Gatlin CC, Ellman MB, Cram TR, Dornan GJ, LaPrade RF (2015) Systematic technique-dependent differences in CT versus MRI measurement of the tibial tubercle-trochlear groove distance. Am J Sports Med 43:675–682
Koeter S, Diks MJ, Anderson PG, Wymenga AB (2007) A modified tibial tubercle osteotomy for patellar maltracking: results at two years. J Bone Joint Surg Br 89:180–185
Koeter S, Horstmann WG, Wagenaar FC, Huysse W, Wymenga AB, Anderson PG (2007) A new CT scan method for measuring the tibial tubercle trochlear groove distance in patellar instability. Knee 14:128–132
Kohlitz T, Scheffler S, Jung T, Hoburg A, Vollnberg B, Wiener E, Diederichs G (2013) Prevalence and patterns of anatomical risk factors in patients after patellar dislocation: a case control study using MRI. Eur Radiol 23:1067–1074
Kuroda R, Kambic H, Valdevit A, Andrish JT (2001) Articular cartilage contact pressure after tibial tuberosity transfer. A cadaveric study. Am J Sports Med 29:403–409
Mani S, Kirkpatrick MS, Saranathan A, Smith LG, Cosgarea AJ, Elias JJ (2011) Tibial tuberosity osteotomy for patellofemoral realignment alters tibiofemoral kinematics. Am J Sports Med 39:1024–1031
Pandit S, Frampton C, Stoddart J, Lynskey T (2011) Magnetic resonance imaging assessment of tibial tuberosity-trochlear groove distance: normal values for males and females. Int Orthop 35:1799–1803
Saudan M, Fritschy D (2000) AT-TG (anterior tuberosity-trochlear groove): interobserver variability in CT measurements in subjects with patellar instability. Rev Chir Orthop Reparatrice Appar Mot 86:250–255
Schoettle PB, Zanetti M, Seifert B, Pfirrmann CW, Fucentese SF, Romero J (2006) The tibial tuberosity-trochlear groove distance; a comparative study between CT and MRI scanning. Knee 13:26–31
Seeley MA, Knesek M, Vanderhave KL (2013) Osteochondral injury after acute patellar dislocation in children and adolescents. J Pediatr Orthop 33:511–518
Seitlinger G, Scheurecker G, Hogler R, Labey L, Innocenti B, Hofmann S (2012) Tibial tubercle-posterior cruciate ligament distance: a new measurement to define the position of the tibial tubercle in patients with patellar dislocation. Am J Sports Med 40:1119–1125
Shih YF, Bull AM, Amis AA (2004) The cartilaginous and osseous geometry of the femoral trochlear groove. Knee Surg Sports Traumatol Arthrosc 12:300–306
Skelley N, Friedman M, McGinnis M, Smith C, Hillen T, Matava M (2015) Inter- and intraobserver reliability in the MRI measurement of the tibial tubercle-trochlear groove distance and trochlea dysplasia. Am J Sports Med 43:873–878
Staeubli HU, Bosshard C, Porcellini P, Rauschning W (2002) Magnetic resonance imaging for articular cartilage: cartilage-bone mismatch. Clin Sports Med 21:417–433
Staubli HU, Durrenmatt U, Porcellini B, Rauschning W (1999) Anatomy and surface geometry of the patellofemoral joint in the axial plane. J Bone Joint Surg Br 81:452–458
Thakkar RS, Del Grande F, Wadhwa V, Chalian M, Andreisek G, Carrino JA, Eng J, Chhabra A (2015) Patellar instability: CT and MRI measurements and their correlation with internal derangement findings. Knee Surg Sports Traumatol Arthrosc. doi:10.1007/s00167-015-3614-8
Wagenaar FC, Koeter S, Anderson PG, Wymenga AB (2007) Conventional radiography cannot replace CT scanning in detecting tibial tubercle lateralisation. Knee 14:51–54
Wagner D, Pfalzer F, Hingelbaum S, Huth J, Mauch F, Bauer G (2013) The influence of risk factors on clinical outcomes following anatomical medial patellofemoral ligament (MPFL) reconstruction using the gracilis tendon. Knee Surg Sports Traumatol Arthrosc 21:318–324
Wilcox JJ, Snow BJ, Aoki SK, Hung M, Burks RT (2012) Does landmark selection affect the reliability of tibial tubercle-trochlear groove measurements using MRI? Clin Orthop Relat Res 470:2253–2260
Wittstein JR, Bartlett EC, Easterbrook J, Byrd JC (2006) Magnetic resonance imaging evaluation of patellofemoral malalignment. Arthroscopy 22:643–649
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no conflicts of interest.
Rights and permissions
About this article
Cite this article
Hinckel, B.B., Gobbi, R.G., Kihara Filho, E.N. et al. Why are bone and soft tissue measurements of the TT-TG distance on MRI different in patients with patellar instability?. Knee Surg Sports Traumatol Arthrosc 25, 3053–3060 (2017). https://doi.org/10.1007/s00167-016-4095-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00167-016-4095-0