Evaluation of Patellar Height After Medial Patellofemoral Ligament Reconstruction in Skeletally Immature Patients: A Radiographic and Functional Analysis
DOI:
https://doi.org/10.63403/re.v32i3.444Keywords:
Patellar instability, Patella alta, Medial patellofemoral ligament reconstruction, Caton-Deschamps, PediatricsAbstract
Introduction: in pediatric patients with open physes and patella alta presenting with recurrent patelofemoral instability (PFI), medial patellofemoral ligament reconstruction (MPFL-R) has proven to be an effective surgical technique. However, its impact on patellar height remains unclear.
Objective: to evaluate whether isolated MPFL reconstruction in skeletally immature patients with patella alta modifies patellar height and correlates with clinical and functional outcomes. We hypothesized that isolated MPFL reconstruction would be associated with decreased patellar height and improved functional scores in this population.
Materials and methods: we conducted an observational, retrospective, and analytical study including 26 patients aged ≤16 years with patella alta, open physes, and PFI treated with MPFL-R. Lysholm, Tegner, and subjective IKDC scores were assessed, and clinically meaningful thresholds (MCID and PASS) were calculated. The Caton- Deschamps index was analyzed on pre- and postoperative lateral radiographs. Statistical significance was set at p <0.05.
Results: of the 32 patients initially included, 26 completed a minimum follow-up of 24 months. Significant improvements were observed in functional scores: Lysholm (43.7 ± 4.7 to 87.1 ± 3.6; p <0.0001; 95% CI, 38.7-44.9), Tegner (2.8 ± 0.8 to 8.8 ± 0.8; p <0.0001; 95% CI, 5.7-6.1), and subjective IKDC (52.3% ± 6.4 to 91.6%± 5.2; p <0.0001; 95% CI, 38.1-44.5). The Caton–Deschamps index significantly decreased. No recurrences orpostoperative complications were recorded.
Conclusion: isolated medial patellofemoral ligament reconstruction in skeletally immature patients with patellofemoral instability and mild patella alta was associated with a significant decrease in the Caton-Deschamps index and a clinically relevant functional improvement, without recurrences or complications, supporting its use as an effective and safe option in selected cases.
Level of evidence: IV. Retrospective Cohort Study
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Hiemstra LA, Kerslake S, Lafave M. Assessment of demographic and pathoanatomic risk factors in recurrent patellofemoral instability. Knee Surg Sports Traumatol Arthrosc. 2017 Dec;25(12):3849-3855. doi: https://www.doi.org/10.1007/s00167-016-4346-0.
Schneider DK, Grawe B, Magnussen RA, Ceasar A, Parikh SN, Wall EJ, et al. Outcomes after isolated medial patellofemoral ligament reconstruction for the treatment of recurrent lateral patellar dislocations: a systematic review and meta-analysis. Am J Sports Med. 2016 Nov;44(11):2993-3005. doi: https://www.doi.org/10.1177/0363546515624673.
Erickson BJ, Nguyen J, Gasik K, Gruber S, Brady J, Shubin Stein BE. Isolated medial patellofemoral ligament reconstruction for patellar instability regardless of tibial tubercle-trochlear groove distance and patellar height: outcomes at 1 and 2 years. Am J Sports Med. 2019 May;47(6):1331-1337. doi: https://www.doi.org/10.1177/0363546519835800.
Sanchis-Alfonso V. Guidelines for medial patellofemoral ligament reconstruction in chronic lateral patellar instability. J Am Acad Orthop Surg. 2014 Mar;22(3):175-182. doi: https://www.doi.org/10.5435/JAAOS-22-03-175.
Aulisa AG, Falciglia F, Giordano M, Savignoni P, Guzzanti V. Galeazzi's modified technique for recurrent patella dislocation in skeletally immature patients. J Orthop Sci. 2012 Mar;17(2):148-155. doi: https://www.doi.org/10.1007/s00776-011-0189-1.
Wagner D, Pfalzer F, Hingelbaum S, Huth J, Mauch F, Bauer G. The influence of risk factors on clinical outcomes following anatomical medial patellofemoral ligament (MPFL) reconstruction using the gracilis tendon. Knee Surg Sports Traumatol Arthrosc. 2013 Feb;21(2):318-324. doi: https://www.doi.org/10.1007/s00167-012-2015-5.
Grannatt K, Heyworth BE, Ogunwole O, Micheli LJ, Kocher MS. Galeazzi semitendinosus tenodesis for patellofemoral instability in skeletally immature patients. J Pediatr Orthop. 2012 Sep;32(6):621-625. doi: https://www.doi.org/10.1097/BPO.0b013e318263a230.
Dejour H, Walch G, Nove-Josserand L, Guier C. Factors of patellar instability: an anatomic radiographic study. Knee Surg Sports Traumatol Arthrosc. 1994;2(1):19-26. doi: https://www.doi.org/10.1007/BF01552649.
Balcarek P, Jung K, Ammon J, Walde TA, Frosch S, Schüttrumpf JP, et al. Anatomy of lateral patellar instability: trochlear dysplasia and tibial tubercle-trochlear groove distance is more pronounced in women who dislocate the patella. Am J Sports Med. 2010 Nov;38(11):2320-2327. doi: https://www.doi.org/10.1177/0363546510373887.
Fabricant PD, Ladenhauf HN, Salvati EA, Green DW. Medial patellofemoral ligament (MPFL) reconstruction improves radiographic measures of patella alta in children. Knee. 2014 Dec;21(6):1180-1184. doi: https://www.doi.org/10.1016/j.knee.2014.07.023.
Hopper GP, Leach WJ, Rooney BP, Walker CR, Blyth MJ. Does degree of trochlear dysplasia and position of femoral tunnel influence outcome after medial patellofemoral ligament reconstruction? Am J Sports Med. 2014 Mar;42(3):716-722. doi: https://www.doi.org/10.1177/0363546513518413.
Howells NR, Barnett AJ, Ahearn N, Ansari A, Eldridge JD. Medial patellofemoral ligament reconstruction: a prospective outcome assessment of a large single centre series. J Bone Joint Surg Br. 2012 Sep;94(9):1202-1208. doi: https://www.doi.org/10.1302/0301-620X.94B9.28738.
Hiemstra LA, Kerslake S, Lafave MR. Patellar apprehension is reduced in most but not all patients after successful patellar stabilization. Am J Sports Med. 2021 Mar;49(4):975-981. doi: https://www.doi.org/10.1177/0363546520988731.
Lykissas MG, Li T, Eismann EA, Parikh SN. Does medial patellofemoral ligament reconstruction decrease patellar height? A preliminary report. J Pediatr Orthop. 2014;34:78-85. doi: https://www.doi.org/10.1097/BPO.0b013e3182a12102.
Luceri F, Roger J, Randelli PS, Lustig S, Servien E. How does isolated medial patellofemoral ligament reconstruction influence patellar height? Am J Sports Med. 2020 Mar;48(4):895-900. doi: https://www.doi.org/10.1177/0363546520902132.
Woodmass JM, Johnson NR, Cates RA, Krych AJ, Stuart MJ, Dahm DL. Medial patellofemoral ligament reconstruction reduces radiographic measures of patella alta in adults. Orthop J Sports Med. 2018 Jan 25;6(1):2325967117751659. doi: https://www.doi.org/10.1177/2325967117751659.
Anagnostakos K, Lorbach O, Reiter S, Kohn D. Comparison of five patellar height measurement methods in 90° knee flexion. Int Orthop. 2011 Dec;35(12):1791-1797. doi: https://www.doi.org/10.1007/s00264-011-1236-4.
Caton JH, Dejour D. Tibial tubercle osteotomy in patello-femoral instability and in patellar height abnormality. Int Orthop. 2010 Feb;34(2):305-309. doi: https://www.doi.org/10.1007/s00264-009-0929-4.
Thévenin-Lemoine C, Ferrand M, Courvoisier A, Damsin JP, Ducou le Pointe H, Vialle R. Is the Caton-Deschamps index a valuable ratio to investigate patellar height in children? J Bone Joint Surg Am. 2011 Apr;93(8):e35. doi: https://www.doi.org/10.2106/JBJS.J.00759.
Shamrock AG, Day MA, Duchman KR, Glass N, Westermann RW. Medial patellofemoral ligament reconstruction in skeletally immature patients: A systematic review and meta-analysis. Orthop J Sports Med. 2019 Jul;7(7):2325967119855023. doi: https://www.doi.org/10.1177/2325967119855023.
Nelitz M, Dreyhaupt J, Reichel H, Woelfle J, Lippacher S. Anatomic reconstruction of the medial patellofemoral ligament in children and adolescents with open growth plates: surgical technique and clinical outcome. Am J Sports Med. 2013 Jan;41(1):58-63. doi: https://www.doi.org/10.1177/0363546512463683.
Hiemstra LA, Kerslake S, Lafave MR, Tucker A. Patella alta is reduced following MPFL reconstruction but has no effect on quality-of-life outcomes in patients with patellofemoral instability. Knee Surg Sports Traumatol Arthrosc. 2021 Feb;29(2):546-552. doi: https://www.doi.org/10.1007/s00167-020-05977-8.
Tegner Y, Lysholm J. Rating systems in the evaluation of knee ligament injuries. Clin Orthop Relat Res. 1985 Sep;(198):43-49.
Lysholm J, Gillquist J. Evaluation of knee ligament surgery results with special emphasis on use of a scoring scale. Am J Sports Med. 1982 May-Jun;10(3):150-154. doi: https://www.doi.org/10.1177/036354658201000306.
Herrera Rodríguez JS, Ponce de León MC, Castañeda JF, Yela H, Díaz A. Transcultural validation and adaptation of the Pedi-IKDC scale for the functional assessment of children that undergo knee surgery. Rev Esp Cir Ortop Traumatol. 2022 Nov-Dec;66(6):500-503. English, Spanish. doi: https://www.doi.org/10.1016/j.recot.2022.06.002.
Jaeschke R, Singer J, Guyatt GH. Measurement of health status. Ascertaining the minimal clinically important difference. Control Clin Trials. 1989 Dec;10(4):407-415. doi: https://www.doi.org/10.1016/0197-2456(89)90005-6.
Tubach F, Ravaud P, Baron G, Falissard B, Logeart I, Bellamy N, et al. Evaluation of clinically relevant states in patient reported outcomes in knee and hip osteoarthritis: the patient acceptable symptom state. Ann Rheum Dis. 2005 Jan;64(1):34-37. doi: https://www.doi.org/10.1136/ard.2004.023028.
Zhang Q, Ying L, Han D, Ye L, Tung TH, Liang J, et al. Arthroscopic reconstruction of the medial patellofemoral ligament in skeletally immature patients using the modified sling procedure: a novel technique for MPFL reconstruction. J Orthop Surg Res. 2023 May;18(1):334. doi: https://www.doi.org/10.1186/s13018-023-03775-9.
Yang DZ, Orellana K, Houlihan NV, Lee J, Carter MV, Ganley TJ, et al. Medial patellofemoral ligament reconstruction improves patella alta. J Pediatr Orthop. 2025 Feb;45(2):e106-e111. doi: https://www.doi.org/10.1097/BPO.0000000000002816.
Grammont PM, Latune D, Lammaire IP. Die behandlung der subluxation und luxation der kniescheibe beim Kind. Technik von Elmslie mit beweglichem weichteilstiel (8-Jahres-Ubersicht) [Treatment of subluxation and dislocation of the patella in the child. Elmslie technic with movable soft tissue pedicle (8 year review)]. Orthopade. 1985 Sep;14(4):229-238. German.
Kraus T, Lidder S, Švehlík M, Rippel K, Schneider F, Eberl R, et al. Patella re-alignment in children with a modified Grammont technique. Acta Orthop. 2012 Oct;83(5):504-510. doi: https://www.doi.org/10.3109/17453674.2012.736168.
Masquijo JJ. Transferencia subperióstica del tendón rotuliano en pacientes esqueléticamente inmaduros con inestabilidad patelofemoral. Artroscopia. 2021;28(3):227-231.
Bartsch A, Lubberts B, Mumme M, Egloff C, Pagenstert G. Does patella alta lead to worse clinical outcome in patients who undergo isolated medial patellofemoral ligament reconstruction? A systematic review. Arch Orthop Trauma Surg. 2018 Nov;138(11):1563-1573. doi: https://www.doi.org/10.1007/s00402-018-2971-4.
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Copyright (c) 2025 Lucas D. Marangoni, Iván J. Bitar, Damián G. Bustos, Luciano Pezzutti, Lucía B. Bitar, Valentín Rivera Bacile, Nicolás Rabello, Javier Masquijo
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