Central Annals of Sports Medicine and Research

Cite this article: Gali JC, Petta GC, Azeredo GB, Gazarini JP, Junior CA, da Silva PAC, et al. (2017) Medial Patellotibial Ligament Insertions Radiographic Landmarks. Ann Sports Med Res 4(5): 1119.

*Corresponding authorJulio Cesar Gali, Department of Orthopaedic Surgery, Catholic University of São Paulo, Rua Joubert Wey, 290. Sorocaba - SP, Brazil, Tel: 55-015-3233-4171; Fax: 55-015-3233-4171; Email:

Submitted: 18 July 2017

Accepted: 18 August 2017

Published: 19 August 2017

ISSN: 2379-0571

Copyright© 2017 Gali et al.

OPEN ACCESS

Keywords•Patellar instability; Patellar ligaments; Radiography

Abstract

Introduction: The medial patellar ligaments are passive stabilizers which act against lateral patellar dislocation during movement. Recently, further attention has been given to the medial patellotibial ligament (MPTL) importance as a restraint to lateral dislocation of the patella, and some reconstruction procedures of this ligament have been describedto treat patellofemoral instability. The aim of this study is to establish the MPTL insertions radiographic landmarks to guide itsanatomical reconstruction and for postoperative radiological control.

Methods: In 12 knees obtained from amputations, the MPTL patellar and tibial insertion sites were identified, and they had their centers recorded with metallic markers. The knees were x-rayed in anteroposterior (AP) and lateral incidences. In the AP x-rays views two lines were drawn: one over the tibial articular surface and another parallel to the first one, passing through the MPTL tibial insertion center. Then the distances from this center to the articular surface and to the medial tibial cortex were measured. The greatest pole-to-pole patellar length was delineated in the lateral x-ray incidences and the distance from the superior patellar pole to the MPTL patellar insertion center was measured.

Results: In the AP x-ray view the average distance between the MPTL tibial insertion center to the tibial articular surface was 22.5 ± 6.2 mm and from this insertion center to the medial tibial cortex was 17.4 ± 6.2 mm. The perpendicular line originated on the MPTL tibial insertion center reached the one over the tibial articular surface at a mean 21.2 ± 7.8 % of this line, from medial to lateral. On the lateral view the MPTL patellar insertion center was established at a mean of 46.6 ± 8.1 % on a line drawn from the superior to the inferior patellar pole. On this incidence the distance from the patellar superior pole to the MPTL insertion center was 20.2 ± 4.0 mm.

Conclusion: It was possible to determine the MPTL insertion sites radiographic location. Such knowledge may be useful for intraoperative reconstruction guidance as well as for postoperative radiological control.

Research Article

Medial Patellotibial Ligament Insertions Radiographic LandmarksJulio Cesar Gali*, Guilherme Camargo Petta, Gustavo Blanco Azeredo, João Paulo Gazarini, Carlos Amaral Junior, and Phelipe Augusto Cintra da Silva Department of Orthopaedic Surgery, Catholic University of São Paulo, Brazil

ABBREVIATIONSAP: Anteroposterior; MPFL: Medial Patellofemoral Ligament;

MPML: Medial Patellar Meniscal Ligament; MPTL: Medial Patellotibial Ligament ; MRI: Magnetic Resonance Imaging

INTRODUCTIONPatellar instability is the more frequent pathology of the knee

which during growth [1]. The incidence of patellar dislocation among the general population of the United States of America is 2.29 to 100,000 individuals yearly, without any risk differences regarding gender, and with greater incidence between the ages of 15 and 19 [2].

Gravesen et al. analyzed 24,154 cases of primary patellar dislocation that occurred in Denmark between 1994 and 2013. The incidence of this pathology was 42 to 100,000 individuals yearly mainly among girls aged 10 to 17. In this ten-year period, the global risk of recurrent dislocation was 22.7%, and it was larger among girls between 10 and 17 years of age (36.8%). The total risk of patellar dislocation of the contralateral knee was 5.8%, and 11.1% among patients between 10 and 17 years of age

- which could indicate the existence of a pathologic basis [3].

Sanders et al., in a cohort study between 1990 and 2000, involving 232 patients skeletally immature who experienced the first episode of patellar dislocation, showed a high recurrencerate, associated with patella alta, with distance between tibial tuberosity and trochlear sulcus greater than 20 mm, and with trochlear dysplasia. The probability of contralateral dislocation was approximately 10% and the occurrence of arthritis after 20 years was 20% [4].

Non surgical treatment is the first option for patellofemoral instability and surgical intervention is recommended in cases of serious chondral lesion and recurrent dislocation [5].

During the movement, the medial patellar ligaments are passive stabilizers which counteract lateral patellar dislocation. The medial patellofemoral ligament (MPFL) is considered the main static medial patellar stabilizer [6-10].

The MPTL, in conjunction with the medial patellomeniscal ligament (MPML), has a secondary role in restraining lateral patellar dislocation.8 Such ligaments are stabilizers mainly in

Central

Gali et al. (2017)Email:

Ann Sports Med Res 4(5): 1119 (2017) 2/4

flexions above 45° and mostly in patellar rotation (responsible for 92% of the stabilization, at a 90° knee flexion) [11]. According to Marcacci et al., the patellotibial medial and patellomeniscal complex ligament have an important role in limiting lateral patellar dislocation and, for Ebied et al., the absence of the MPTL may lead to an increase in translation and even lateral subluxation [12].

The MPFLreconstruction for the treatment of patellar instability has brought excellent functional results [13]. However, there is few reference in the literature about MPTL surgical reconstruction. Some authors recommend its reconstruction together with the reconstruction of the MPFL, [12,14-18] or with the vastus medialis obliquus advancement [19,20]. Others solely recommend the isolated MPTL reconstruction [21]. However, the reconstruction proposed by Drez et al. is the only one that nears an anatomical reconstructions, i.e. a reconstruction performed in the original ligament attachmentsites [14].

The MPTL anatomy has been studied earlier thoroughly [22]. However, we found just one study on the radiographic positioning of its insertion sites [23]. The aim of our research was to describe the MPTL insertion sites radiographic position in order to provide guidelines for its anatomical reconstruction and for postoperative radiographic evaluation.

METHODSOur research was approved by the Ethics Committee of our

University. Identifying the radiographic location of the MPTL insertion sites required 12 knees obtained from amputations. Immediately following the amputations, the specimens were frozen and kept below -15°C. The knees were then removed from the freezer and allowed to thaw at room temperature the night prior to dissection. The skin and subcutaneous tissues were removed, the fascia was opened and the MPTL was dissected from its origin, in the patella, up to its tibial insertion.

The knees were x-rayed in anteroposterior (AP) and lateral incidences. In the AP x-rays views three lines were drawn: one over the tibial articular surface, another parallel to the first one, passing through the tibial MPTL radiographic insertion center and another, perpendicular to the others, from the tibial radiographic insertion to the tibial articular surface. Then the distances from this center to the tibial articular surface (d1) and from this point to the medial tibial cortex (d2) were measured. The percentage where the vertical line reached the one drawn over the tibial articular surface, from medial to lateral, was also calculated (Figure 1).

The greatest pole-to-pole patellar line was delineated in the lateral x-ray incidences and its length and the distance from the superior patellar pole to the MPTL patellar insertion center were measured. The percentage where the MPTL patellar insertion center was located at the greatest pole-to-pole line, from superior to inferior, was calculated (Figure 2).

Two knee surgeons carried out the evaluations. The Wilcoxon Signed-Rank Test (at a 95% reliability rate) was used to analyze whether the measures were significantly different.

RESULTSPatients’ age at the time of amputation ranged from 43 to 93

(average age 62.9 years). Four individuals were male and eight were female. Seven of the knees were right knees and five, left.

In the AP x-ray view the average distance between the MPTL tibial insertion center to the tibial articular surface was 22.5 ± 6.2 mm (varying from 10.0 to 31.0 mm) and from this insertion center to the medial tibial cortex was 17.4 ± 6.2 mm (varying from 10.0 to 29.0). The perpendicular line originated on the MPTL tibial insertion center reached the one over the tibial articular surface at a mean of 21.2 ± 7.8 % of this line, from medial to lateral (varying from 12.8 to 38.6%).

On the lateral view the MPTL patellar insertion center was established at a mean of 46.6 ± 8.1 % on the line drawn from the superior to the inferior patellar pole (varying from 35 to 63.8%). On this incidence the distance from the patellar superior pole to the MPTL insertion center varied from 14.0 a 30.0 mm (average 20.2 ± 4.0 mm). All the results are grouped in Table 1.

The Wilcoxon test p-value was 0.287 (> 0.05). Thus, we have considered that the measurements taken by both researchers were relatively the same.

DISCUSSIONThe MPTL is responsible for 92% of the patellofemoral

stability at a 90° knee flexion [10]. There are various surgical techniques for its reconstruction, either isolated or in conjunction with other procedures [12, 14-21].

In a review article on high resolution magnetic resonance imaging (MRI) of the patellar retinaculum Thawait et al. [24] informed that MPTL ligament is a very thin structure within layer III which can be visible at the tibial plateau level.

Dirim et al. [25] in a MRI investigation using seven fresh frozen cadaveric knees (mean age at death, 83.4 years; range, 74-93 years) showed that MPTL insertions are at the medial aspect of the tibia immediately below the joint line and at the lower part of the patella and proximal part of the patellar tendon. The aim of this study was to describe the radiographic position of the MPTL insertion sites in order to assist in its accurate intraoperative positioning, through the image intensifier, as well as evaluate the placement of bone tunnels postoperatively.

By dissecting 12 knees, we determined the MPTL origin and the insertion attachments, and through the radiographic exam, the mean position of the MPTL insertion centers in the anatomic specimens was in a point 22.5 ± 6.2 mm distant from the tibial articular surface and 17.4 ± 6.2 mm distant from the medial tibial cortex at the tibia, in the AP x-ray view, while at the patella it was 20.2 ± 4.0 mm from the patellar superior pole, in lateral x-ray view.

On the other hand, Hinckel et al. [23] recently published their outcomes about MPTL insertion centersradiographic location. In a study with 10 cadavers’ knees (median age 67.4 years) they reported that MPTL tibial insertion site is 9.4 ± 4.9 mm distant from the joint and 23.8 ± 4.3 mm distant from the medial tibial cortex, in the AP x-ray view, while the patellar insertion site, in lateral x-ray view, it was 4.8 ± 4.7 mm from the patellar inferior pole, results very different from ours.

This study has some limitations: the MPTL insertions

Central

Gali et al. (2017)Email:

Ann Sports Med Res 4(5): 1119 (2017) 3/4

Table 1 : Demographic data andresults.

Age Gender Side

Lateral View AP View

Patellar-Lenght (mm)

Distancefromthepa-tellar superior pole totheinsertion point (mm)

Location of the inser-tion site at greater patellar length (%)

Length of tibial articular surface (mm)

Distance from the insertion to the tibial articular surface (mm)

Distance from the insertion to the medial tibial cor-tex (mm)

Location of the inser-tion of the tibial articu-lar line (%)

1 81 F R 40 14 35.0% 76 29 12 15.7%

2 70 F R 40 21 52.5% 78 20 10 12.8%

3 53 F L 42 16 38.1% 78 20 13 16.6%

4 82 M R 47 30 63.8% 84 27 12 14.2%

5 73 M R 48 20 41.6% 84 20 17 20.2%

6 65 M L 49 20 40.8% 87 22 18 20.6%

7 48 F R 43 18 41.8% 82 30 12 14.6%

8 55 M L 41 18 43.9% 87 31 16 18.3%

9 82 F R 39 20 51.2% 75 22 29 38.6%

10 93 F L 45 20 44.4% 85 25 20 23.5%

11 85 F R 44 23 52.2% 78 10 24 30.7%

12 83 F L 43 23 53.4% 90 15 26 28.8%

Mean 72.5 Female Right 43.4 20.2 46.6% 82.0 22.5 17.4 21.2%

SD 14.4 8 7 3.2 4.0 8.1% 4.9 6.2 6.2 7.8%

Max 93.0 Male Left 49.0 30.0 63.8% 90.0 31.0 29.0 38.6%

Min 48.0 4 5 39.0 14.0 35.0% 75.0 10.0 10.0 12.8%

Figure 1 Lines drawn at AP radiography, for measures. Figure 2 Lines drawn at lateral radiography, for measures.

radiographic landmarks analyses were carried out on knees without history of lateral patellar instability and patients’ average age (62.9 years) at amputation time was greater than those where patellar dislocation is more common.

CONCLUSIONThe outcomes of our study could determine the MPTL insertion

sites radiographic landmarks. It may be useful for intraoperative reconstruction guidance as well as for postoperative radiological control.

REFERENCES1. Hasler CC, Studer D. Patella instability in children and adolescents.

Efort Open Rev. 2017; 1: 160-166.

2. Waterman BR, Belmont PJ, Owens BD. Patellar dislocation in the United States: role of sex, age, race, and athletic participation. J Knee Surg. 2012; 25: 51-57.

3. Gravesen KS, Kallemose T, Blønd L, Troelsen A, Barfod KW. High incidence of acute and recurrent patellardislocations: a retrospective nationwide epidemiological study involving 24.154 primary dislocations.Knee Surg Sports Traumatol Arthrosc. 2017; 23: 4594-4597.

Central

Gali et al. (2017)Email:

Ann Sports Med Res 4(5): 1119 (2017) 4/4

4. Sanders TL, Pareek A, Hewett TE, Stuart MJ, Dahm DL, Krych AJ. Highrate of recurrentpatellardislocation in skeletallyimmaturepatients: a long-term population-based study. Knee Surg Sports Traumatol Arthrosc. 2017; 15.

5. DeFroda SF, Gil JA, Boulos A, Cruz AI Jr. Diagnosis and Management of Traumatic Patellar Instability in the Pediatric Patient.Orthopedics. 2017; 6: 1-8.

6. Conlan T, Garth WP Jr, Lemons JE. Evaluation of the medial soft-tissue restraints of the extensor mechanism of the knee. J Bone Joint Surg Am. 1993; 75: 682-693.

7. Desio SM, Burks RT, Bachus KN. Soft tissue restraints to lateral patellar translation in the human knee.Am J Sports Med. 1998; 26: 59-65.

8. Hautamaa PV, Fithian DC, Kaufman KR, Daniel DM, Pohlmeyer AM. Medial soft tissue restraints in lateral patellar instability and repair.Clin Orthop Relat Res. 1998; 349: 174-182.

9. Panagiotopoulos E, Strzelczyk P, Herrmann M, Scuderi G. Cadaveric study on static medial patellar stabilizers: the dynamizing role of the vastus medialis obliquus on medial patellofemoral ligament. Knee Surg Sports Traumatol Arthrosc. 2006; 14: 7-12.

10. Philippot R, Boyer B, Testa R, Farizon F, Moyen B. The role of the medial ligamentous structures on patellar tracking during knee flexion. Knee Surg Sports Traumatol Arthrosc. 2012; 20: 331-336.

11. Marcacci M, Zaffagnini S, Bruni D, Muccioli GMM, Giordano G, Alvarez PG. MPTL (Medial Patellotibialligament) Reconstruction. In: Zaffagnini S, Dejour D, Arendt EA. Patellofemoral Pain, Instability, and Arthritis. Springer: Heidelberg; 2010; 185-192.

12. Ebied AM, El-Kholy W. Reconstruction of the medial patello-femoral and patello-tibial ligaments for treatment of patellar instability. Knee Surg Sports Traumatol Arthrosc. 2012; 20: 926-932.

13. Buckens CF, Saris DB. Reconstruction of the medial patellofemoral ligament for treatment of patellofemoral instability: a systematic review. Am J Sports Med. 2010; 38: 181-188.

14. Drez D, Edwards TB, Williams CS. Results of medial patellofemoral ligament reconstruction in the treatment of patellar dislocation. Arthroscopy. 2001; 17: 298-306.

15. Nietosvaara Y, Paukku R, Palmu S, Donell ST. Acute patellar dislocation in children and adolescents. Surgical technique. J Bone Joint Surg Am. 2009; 91:139-145.

16. Giordano M, Falciglia F, Aulisa AG, Guzzanti V. Patellar dislocation in skeletally immature patients: semitendinosous and gracilis augmentation for combined medial patellofemoral and medial patellotibial ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2012; 20: 1594-1598.

17. Sobhy MH, Mahran MA, Kamel EM. Midterm results of combined patellofemoral and patellotibial ligaments reconstruction in recurrent patellar dislocation. Eur J Orthop Surg Traumatol. 2013; 23: 465-470.

18. Hinckel BB, Gobbi RG, Bonadio MB, Demange MK, Pécora JR, Camanho GL. Reconstruction of medial patellofemoral ligament using quadriceps tendon combined with reconstruction of medial patellotibial ligament using patellar tendon: initial experience. Rev Bras Ortop. 2016; 51: 75-82.

19. Myers P, Williams A, Dodds R, Bülow J. The three-in-one proximal and distal soft tissue patellar realignment procedure. Results, and its place in the management of patellofemoral instability. Am J Sports Med. 1999; 27: 575-579.

20. Oliva F, Ronga M, Longo UG, Testa V, Capasso G, Maffulli N. The 3-in-1 procedure for recurrent dislocation of the patella in skeletally immature children and adolescents. Am J Sports Med. 2009; 37: 1814-1820.

21. Zaffagnini S, Grassi A, Marcheggiani Muccioli GM, Luetzow WF, Vaccari V, Benzi A, Marcacci M. Medial patellotibial ligament (MPTL) reconstruction for patellar instability. Knee Surg Sports Traumatol Arthrosc. 2014; 22: 2491-2498.

22. Gali JC, Amaral Jr C, Nogueira F, Nakamichi Y, Santos NB, Silva PAC. Medial Patellotibial Ligament Anatomy and Histology. Ann Sports Med Res 2017; 4 :1111.

23. Hinckel BB, Gobbi RG, Demange MK, Pereira CAM, Pécora JR, Natalino RJM, Miyahira L, Kubota BS, Camanho GL. Medial Patellofemoral Ligament, Medial Patellotibial Ligament, and Medial Patellomeniscal Ligament: Anatomic, Histologic, Radiographic, and Biomechanical Study. Arthroscopy. 2017; 26: 30392-30394.

24. Thawait SK, Soldatos T, Thawait GK, Cosgarea AJ, Carrino JA, Chhabra A. High resolution magnetic resonance imaging of the patellar retinaculum: normal anatomy, common injury patterns,and pathologies. Skeletal Radiol. 2012; 41:137-148.

25. Dirim B, Haghighi P, Trudell D, Portes G, Resnick D. Medial patellofemoral ligament: cadaveric investigation of anatomy with MRI, MR arthrography, and histologic correlation. AJR Am J Roentgenol. 2008; 191: 490-498.

Gali JC, Petta GC, Azeredo GB, Gazarini JP, Junior CA, da Silva PAC, et al. (2017) Medial Patellotibial Ligament Insertions Radiographic Landmarks. Ann Sports Med Res 4(5): 1119.

Cite this article