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Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes
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Original article
Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes S. Otsuki ∗ , Y. Okamoto , T. Murakami , K. Nakagawa , N. Okuno , H. Wakama , M. Neo Department of orthopedic surgery, Osaka medical college, 2-7 Daigakumachi Takatsuki, 569-8686 Osaka, Japan
a r t i c l e
i n f o
Article history: Received 18 August 2017 Accepted 3 January 2018 Keywords: Patellar instability Patella alta Middle age Trochleoplasty
a b s t r a c t Introduction: Although several surgical treatments for patellar instability with patella alta have been reported, the clinical outcomes and optimal surgical procedures for patellar instability with patella alta in middle-aged patients are still controversial. We hypothesized that optimal surgical procedures for patellar instability with patella alta in middle-aged patients may induce good clinical outcomes with better patellofemoral geometry. Materials and methods: Twelve middle-aged patients with a mean age of 44 years (range: 40–55 years), who presented with patellar instability and patella alta, were treated with a combination of several surgeries, such as medial patellofemoral ligament (MPFL) reconstruction, trochleoplasty, lateral release, and three-dimensional transfer of the tibial tuberosity, based on a surgical algorithm. Patellar position and clinical outcomes were evaluated postoperatively. The mean follow-up time was 41.5 months (range: 24–72 months). Results: Patellar position altered from 1.31 (1.21–1.53) preoperatively to 0.88 (0.69–1.06) postoperatively on the Caton-Deschamps Index (p < 0.01). The tibial tuberosity–trochlear groove (TT-TG) distance altered from 21.8 mm (20.1–25.8 mm) to 10.3 mm (5.1–14.7 mm), and patellar tilt ranged from 28.1◦ (21–40◦ ) to 14.6◦ (5–28◦ ), respectively (p < 0.01). Clinical outcomes on the Lysholm and Kujala scales improved from 43.1 and 38.4 to 86.7 and 78.3, respectively, at final follow-up (p < 0.01). Surgical treatment that included trochleoplasty resulted in better outcomes than other surgical combinations without trochleoplasty (p < 0.05). Sulcus angle and postoperative patellar tilt improved more in those who underwent trochleoplasty than in those who did not (p < 0.05). Discussion: Surgical treatment for patellar instability with patella alta in middle-aged patients resulted in improved clinical outcomes. In particular, a combination surgery including trochleoplasty resulted in the greatest improvement in case of severe trochlear dysplasia. Level of evidence: IV. Retrospective case series study. © 2018 Elsevier Masson SAS. All rights reserved.
1. Introduction Patellar instability after recurrent patellar dislocation is associated with patellofemoral dysplasia, such as patella alta, trochlear dysplasia, patellar dysplasia, and original malalignment [1,2]. Patellar instability and patellar dislocation occur most frequently in teenagers, and numerous surgical techniques have been described, including trochleoplasty, medial patellofemoral ligament (MPFL) reconstruction, and transfer of the tibial tuberosity [3]. Trochleoplasty is an established and accepted technique for the treatment of patellar instability to address a shallow or
∗ Corresponding author. E-mail address: [email protected] (S. Otsuki).
absent trochlear groove [4]. Trochleoplasty was first described by Masse, who remodeled the trochlear groove [5], with good clinical outcomes [6–9]. If patellar stability is not restored, it can lead to articular cartilage injury, pain, decreased activity, and patellofemoral osteoarthritis (OA) [10]. MPFL reconstruction is another surgical approach to address patellofemoral instability. With regard to the factors that impact clinical outcomes following MPFL reconstruction, Enderlein et al. reported that age greater than 30, obesity, cartilage injury, and female sex are predictors of poor subjective outcome following surgery [11]. In previous studies, we have treated patellar instability with patella alta, using a three-dimensional (3D) transfer of the tibial tuberosity [12] and have shown that the clinical outcomes depend on the age of the patient at the time of surgery, which also correlates with cartilage damage [13]. The main problem with
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Table 1 Patient characteristics and radiological parameters. Patients (M/F) Age (y.o.) BMI (kg/m2 ) FTA (◦ ) K/L grade Patellofemoral OA Follow-up (months)
12 (2/10) 44 (40–55) 24.4 (19.6–29.8) 175 (169–180) I; 2, II; 7, III; 3 I; 1, II; 5, III; 5, IV: 1 41.5 (24–72)
BMI: body mass index; K/L: Kellgren-Lawrence; OA: osteoarthritis.
patellar instability during middle age is that most patients have already progressed to the point of secondary osteoarthritic changes, including osteophyte formation and cartilage erosion. These aging and osteoarthritic changes may prevent better patellofemoral congruity after general patellofemoral reconstruction surgery. Moreover, an additional option for trochleoplasty might be needed for improving patellofemoral geometry. Although several surgical treatments for patellar instability have been reported, the optimal clinical approach for patellar instability with patella alta in middle-aged patients is still controversial. The purpose of this study was to clarify the optimal surgical approach for patellar instability with patella alta based on a surgical algorithm and to assess the effect of trochleoplasty in middle-aged patients. The hypothesis was that optimal surgical procedures for patellar instability with patella alta in middle-aged patients may induce good clinical outcomes with better patellofemoral geometry. 2. Materials and methods 2.1. Enrollment From 2008 to 2015, we operated on 42 patients (47 knees) for recurrent patellar instability at our institution. The inclusion criteria for this study were patellar instability with patella alta and age from 40 to 70 years. We excluded 28 patients (32 knees) who were younger than 40, one patient (one knee) older than 70, and 2 patients (2 knees) who were older than 40, but did not have patella alta. Ultimately, 12 patients (2 males and 10 females) were analyzed in this study. The mean age was 44 years (40–55 years) and the mean body mass index (BMI) was 24.4 kg/m2 (19.6–29.8 kg/m2 ). The mean femorotibial angle (FTA) was 175◦ (169–180◦ ). On the Kellgren-Lawrence Scale, 2 patients had grade I knee OA, 7 had grade II, and 3 had grade III OA. Meanwhile, 1 patient had stage I patellofemoral OA, 5 had stage II, 5 had stage III, and 1 had stage IV OA, based on Iwano’s classification [14]. The mean time to final follow-up was 41.5 months (24–72 months) (Table 1). This study was performed in accordance with a protocol approved by the institutional review board of Osaka Medical College (no. 1291).
2.3. Surgical technique Three-dimensional transfer of the tibial tuberosity has been described previously [12]. Briefly, an anteromedial to posterolateral osteotomy of the tibial tuberosity was performed and the tibial tuberosity was transferred to an anteromedial and distal position based on the degree of patella alta and TT-TG distance to restore normal patellar position. Trochleoplasty was performed in two ways. Sulcus-deepening osteotomy was performed when the articular cartilage had an International Cartilage Repair Society (ICRS) cartilage grade lower than grade II [19]. When the cartilage had already eroded at the patellofemoral joint, a v-shaped sulcus-deepening osteotomy was performed. After removing the osteophytes, the location and depth of the sulcus-deepening osteotomy was determined according to (a) the length of the lateral facet and (b) the cleft of the patella, respectively (Fig. 1A and B). After creating the lateral facet, the new joint surface was coated with bone wax to prevent bleeding and arthrofibrosis. When the cartilage was preserved at the medial facet (Fig. 1C), sulcus deepening was performed according to Dejour’s procedure [19] and fixed with fiber wire (Fig. 1D). Postoperative X-ray was shown in Fig. 1D. MPFL reconstruction was performed using the gracilis tendon [20,21]. The tendon was fitted with No. 0 FiberWire non-absorbable suture baseball stitches (Arthrex, Naples, FL, US) at each end. After making a bone tunnel on the femoral side, the gracilis was fixed to the lateral femoral cortex with an Endobutton CL (Smith & Nephew, Memphis, TN, US). Subsequently, it was fixed to 2 holes in the patella, using 4.75 mm SwiveLock (Arthrex) with a tension of 10 N, using a tension meter at 30◦ of knee flexion based on biomechanical analysis [22]. The surgical procedures for all cases are shown in Table 3. All cases involved 3D transfer of the tibial tuberosity due to patella alta. Five patients had Dejour type A trochlear dysplasia, 2 had type B, 3 had type C, and 2 had type D. Four patients with Dejour type B and D dysplasia were treated with trochleoplasty. Three patients with patellar instability displayed a lateral shift at 60◦ on a skyline view and were treated with MPFL reconstruction. The remaining 9 patients underwent medial plication. Lateral release was performed in all cases. 2.4. Rehabilitation All surgical procedures were allowed the same protocol; Passive ROM exercise was allowed from the first day after surgery. Fifty percent weight-bearing was started 2 weeks after surgery and full weight-bearing was permitted 4 weeks after surgery. 2.5. Assessment method Patellar position and clinical outcomes were compared pre- and postoperatively. Patellar position was measured using the CatonDeschamps Index, TT-TG distance, and patellar tilt, and the clinical outcomes were evaluated using Lysholm and Kujala scores.
2.2. Surgical algorithm for patellar instability with patella alta 2.6. Statistical analysis Surgical treatment was selected based on our algorithm (Table 2). Patellar height was evaluated using the Caton-Deschamps Index [15,16], trochlear dysplasia was classified using the Dejour classification [17], and lateral shift was evaluated on plain radiographs using a skyline view at 30◦ and 60◦ of knee flexion. Malalignment of the patella and lower extremity was evaluated by patellar tilt and tibial tuberosity–trochlear groove (TT-TG) distance with CT scan [16,18]. Based on this composite evaluation, a combination of surgical procedures such as transfer of the tibial tuberosity, MPFL reconstruction, medial plication, release of the lateral retinaculum, and trochleoplasty for sulcus deepening were selected.
Pre- and postoperative results were compared using a paired T-test and JMP Pro software (version 11.2.0, SAS, Cary, NC, US). A comparison of clinical outcomes was performed using the MannWhitney U test. A p-value of < 0.05 was considered statistically significant. 3. Results Postsurgical patellar position was located from 1.31 (1.21–1.53) to 0.88 (0.69–1.06) on the Caton-Deschamps index, with a TT-TG distance of 21.8 mm (20.1–25.8 mm) to 10.3 mm (5.1–14.7 mm),
Please cite this article in press as: Otsuki S, et al. Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes. Orthop Traumatol Surg Res (2017), https://doi.org/10.1016/j.otsr.2018.01.003
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Table 2 Algorism for patellar instability with patella alta. Proximal
Distal
Trochlea dysplasia
Lateral sift
Patella malalignment
Patella alta
Mal-rotation
CD: Caton-Deschamps index; TT-TG: tibial tuberosity–trochlear groove distance; MPFL: medial patellofemoral ligament.
Fig. 1. Surgical procedure for trochleoplasty. A and B. Planning of a v-shaped sulcus-deepening osteotomy. V-shaped osteotomy is planned based on the (a) length and (b) crest of the patella. C and D. V-shaped osteotomy of the femoral trochlea performed at the site of sclerotic bone. After creating the lateral facet, the new joint surface is coated with bone wax. When the cartilage is preserved, especially at the medial facet, sulcus deepening is performed according to Dejour’s procedure and fixed with fiber wire. E and F. Pre- and postoperative X-ray were shown. Table 3 Surgical procedures for all cases. Case
Age, gender
Caton-Deschamps
3D transfer
Dejour
Trochleoplasty
1 2 3 4 5 6 7 8 9 10 11 12
46 F 55 M 43 F 44 F 45 F 40 M 47 F 43 F 43 F 44 F 45 F 46 F
1.24 1.32 1.21 1.35 1.21 1.35 1.35 1.53 1.22 1.28 1.53 1.24
O O O O O O O O O O O O
D D B B C A A C A C A A
O O O O
MPFL
Medial plication
Lateral release
PFOA
O O
O O O O O O O O O O O O
3 4 3 3 2 3 2 2 1 2 2 3
O O O O O O O O O O
3D transfer: three-dimensional transfer of tibial tuberosity; MPFL: medial patellofemoral ligament; PFOA: patellofemoral osteoarthritis.
and 28.1◦ (21–40◦ ) to 14.6◦ (5–28◦ ) of patellar tilt (Table 4, p < 0.01). The mean Lysholm and Kujala scores improved significantly from 43.1 to 86.7, and 38.4 to 78.3, respectively (Fig. 2, p < 0.01). To further assess the surgical factors related to clinical outcomes, we focused on patellar medialization and trochleoplasty. Although there was no significant difference between MPFL reconstruction and plication of the medial retinaculum for medialization, the 4 patients with Dejour type B or D dysplasia, who underwent trochleoplasty, showed significantly greater improvement than the
other 8 patients who did not undergo trochleoplasty (Table 5, p < 0.05). The preoperative sulcus angle in those who underwent trochleoplasty was significantly higher than in those that did not undergo trochleoplasty (Table 6, p = 0.003), but no significant difference was detected postoperatively. Patellar tilt was significantly improved with or without trochleoplasty (p < 0.01). However, postoperative patellar tilt in those who underwent trochleoplasty improved more than the patellar tilt in those who did not undergo trochleoplasty.
Please cite this article in press as: Otsuki S, et al. Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes. Orthop Traumatol Surg Res (2017), https://doi.org/10.1016/j.otsr.2018.01.003
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Fig. 2. Comparison of pre- and postoperative clinical outcomes. With combination surgery, the mean Lysholm and Kujala scores significantly improved from 43.1 to 86.7 and from 38.4 to 78.3, respectively (p < 0.01). Table 4 Changes of patellofemoral geometry.
Patellar position Caton-Deschamps TT-TG Patellar tilt
Preoperative
Final F/U
p-value
1.31 (1.21–1.53) 21.8 (20.1–25.8) 28.1 (21–40)
0.88 (0.69–1.06) 10.3 (5.1–14.7) 14.6 (5–28)
< .01 < .01 < .01
F/U: follow up; TT-TG: tibial tuberosity–trochlear groove distance. Table 5 Effect of patellar medializationand trochleoplasty for clinical outcome. Lysholm
Kujala
Patellar medialization
MPFL
plication
p-value
MPFL
plication
p-value
Preoperative Final F/U Improvement Trochleoplasty Preoperative Final F/U Improvement
39.6 76.9 37.3 + 33.5 86.8 53.3
42.9 85.3 42.4 − 40.9 74.9 34.0
n.s. n.s. n.s.
35.0 84.7 49.7 + 38.8 92 53.3
45.7 90.7 45 − 44.8 82.8 37.4
n.s. n.s. n.s.
.017 n.s. .020
n.s. n.s. .005
Clinical outcome of Lysholm and Kujala scores were compared between MPFL reconstruction and plication of medial retinaculum, and with or without trochleoplasty. MPFL: medial patellofemoral ligament; F/U: follow up. Improvement = Final F/U − Preoperative Score. Table 6 Radiographical changes with trochleoplasty. Trochleoplasty Sulcus angle Preoperative Postoperative Patellar tilt Preoperative Postoperative
+
−
p-value
158.0 ± 6.5 141.5 ± 4.2*
144.3 ± 5.2 144.4 ± 4.5
.003 .31
28.0 ± 6.1 9.0 ± 4.8*
28.2 ± 6.7 17.1± 5.5*
.97 .03
Comparison between pre- and postoperative parameters and significant difference were detected in asterisk (*). * p < 0.01.
4. Discussion The most important finding of this study was that the clinical outcomes for patellar instability with patella alta in middleaged patients significantly improved with surgical treatment. In particular, a combination of surgical procedures including trochleoplasty for Dejour type B and D trochlear dysplasia improved patellofemoral geometry, with good clinical outcomes.
With regard to the clinical outcomes of sulcus-deepening trochleoplasty, Ntagiopoulos et al. reported satisfactory restoration of patellar stability and improvement of knee scores, with no complications due to subsequent arthritis at midterm follow-up [6]. Likewise, several reports of sulcus-deepening trochleoplasty have shown good clinical outcomes with long-term results [7–9]. However, sulcus-deepening trochleoplasty requires careful attention to detail [23]. Patellofemoral arthritis, skeletal immaturity, and isolated patellofemoral pain are contra-indications for trochleoplasty [24]. Although trochleoplasty is not indicated for patellofemoral arthritis [19] and arthrofibrosis after trochleoplasty has been reported [23], trochleoplasty can permanently restore patellofemoral stability [4]. In the present series, we performed a combination surgery based on a surgical algorithm, which included trochleoplasty for Dejour type B and D trochlear dysplasia [16]. The first of these patients experienced a contracture caused from the two weeks’ immobilization and performed manipulation; otherwise, there were no limitations in knee range of motion. From the second patient onward, rehabilitation started strictly on postoperative day 1. Physicians should consider a strong fixation procedure such as trochleoplasty in combination with MPFL reconstruction to achieve patellar stability with early exercise [25]. Patellofemoral OA is a relatively common condition that affects up to 24% of women and 11% of men older than 55 years who have symptomatic OA of the knee [26]. Isolated patellofemoral arthritis is highly associated with patella alta and trochlear dysplasia [27]. Van Haver et al. investigated trochlear dysplasia and patellofemoral biomechanics in a cadaveric study, and reported that the relationship between the shape of the trochlea and patellofemoral biomechanics can provide insight into the short-term effects (maltracking, increased pressure, and instability) and long-term effects (OA) of different types of trochlear dysplasia [28]. The reported surgical options for patellofemoral OA in middle-aged patients include patellectomy [11,12], lateral retinacular release [29], lateral patellar facetectomy, or a combination of these [30]. If patients with patellar instability and patella alta undergo these surgeries, patellar instability may be accelerated by of the loss of patellofemoral congruity. Establishing better patellofemoral congruity might induce better clinical outcomes and has potential of cartilage remodeling after surgery. This study has several limitations. It is a retrospective study with a short-term follow-up period involving a very small number of heterogeneous patients because most of the patients had received surgical treatment within teenager and middle-aged
Please cite this article in press as: Otsuki S, et al. Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes. Orthop Traumatol Surg Res (2017), https://doi.org/10.1016/j.otsr.2018.01.003
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patients of patellar instability with alta are not so much. Although further research is needed, good clinical outcomes were obtained in middle-aged patients with patellar instability and patella alta. Studies with a larger number of patients and longer follow-up are required and second-look arthroscopy might be interesting for evaluating cartilage regeneration. 5. Conclusions Appropriate surgical treatment for patellar instability with patella alta in middle-aged patients results in improved clinical outcomes. In particular, a combination surgery including trochleoplasty is of interest in case of severe trochlear dysplasia. Disclosure of interest The authors declare that they have no competing interest. References [1] Wibeeg G. Roentgenographs and anatomic studies on the femoropatellar joint: with special reference to chondromalacia patellae. Acta Orthop Scand 1941;12:319–410. [2] Colvin AC, West RV. Patellar instability. J Bone Joint Surg Am 2008;90:2751–62. [3] Weber AE, Nathani A, Dines JS, Allen AA, Shubin-Stein BE, Arendt EA, et al. An algorithmic approach to the management of recurrent lateral patellar dislocation. J Bone Joint Surg Am 2016;98:417–27. [4] Laprade RF, Cram TR, James EW, Rasmussen MT. Trochlear dysplasia and the role of trochleoplasty. Clin Sports Med 2014;33:531–45. [5] Masse Y. [Trochleoplasty. Restoration of the intercondylar groove in subluxations and dislocations of the patella]. Rev Chir Orthop Reparatrice Appar Mot 1978;64:3–17. [6] Ntagiopoulos PG, Byn P, Dejour D. Midterm results of comprehensive surgical reconstruction including sulcus-deepening trochleoplasty in recurrent patellar dislocations with high-grade trochlear dysplasia. Am J Sports Med 2013;41:998–1004. [7] Fucentese SF, Zingg PO, Schmitt J, Pfirrmann CWA, Meyer DC, Koch PP. Classification of trochlear dysplasia as predictor of clinical outcome after trochleoplasty. Knee Surg Sports Traumatol Arthrosc 2011;19:1655–61. [8] Donell ST, Joseph G, Hing CB, Marshall TJ. Modified Dejour trochleoplasty for severe dysplasia: operative technique and early clinical results. Knee 2006;13:266–73. [9] Rouanet T, Gougeon F, Fayard JM, Rémy F, Migaud H, Pasquier G. Sulcus deepening trochleoplasty for patellofemoral instability: a series of 34 cases after 15 years postoperative follow-up. Orthop Traumatol Surg Res 2015;101:443–7. [10] Fithian DC, Paxton EW, Stone ML, Silva P, Davis DK, Elias DA, et al. Epidemiology and natural history of acute patellar dislocation. Am J Sports Med 2004;32:1114–21. [11] Enderlein D, Nielsen T, Christiansen SE, Faunø P, Lind M. Clinical outcome after reconstruction of the medial patellofemoral ligament in patients with recurrent patella instability. Knee Surg Sports Traumatol Arthrosc 2014;22:2458–64.
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[12] Otsuki S, Nakajima M, Oda S, Hoshiyama Y, Fujiwara K, Jotoku T, et al. Threedimensional transfer of the tibial tuberosity for patellar instability with patella alta. J Orthop Sci 2013;18:437–42. [13] Otsuki S, Nakajima M, Fujiwara K, Okamoto Y, Iida G, Murakami T, et al. Influence of age on clinical outcomes of three-dimensional transfer of the tibial tuberosity for patellar instability with patella alta. Knee Surg Sports Traumatol Arthrosc 2016:1–5. [14] Iwano T, Kurosawa H, Tokuyama H, Hoshikawa Y. Roentgenographic and clinical findings of patellofemoral osteoarthrosis. With special reference to its relationship to femorotibial osteoarthrosis and etiologic factors. Clin Orthop Relat Res 1990:190–7. [15] Caton J, Deschamps G, Chambat P, Lerat JL, Dejour H. [Patella infera. Apropos of 128 cases]. Rev Chir Orthop Reparatrice Appar Mot 1982;68:317–25. [16] Dejour H, Walch G, Nove-Josserand L, Guier C. Factors of patellar instability: an anatomic radiographic study. Knee Surg Sports Traumatol Arthrosc 1994;2:19–26. [17] Dejour D, Le Coultre B. Osteotomies in patello-femoral instabilities. Sports Med Arthrosc 2007;15:39–46. [18] Otsuki S, Nakajima M, Okamoto Y, Oda S, Hoshiyama Y, Iida G, et al. Correlation between varus knee malalignment and patellofemoral osteoarthritis. Knee Surg Sports Traumatol Arthrosc 2014;24:176–81. [19] Dejour D, Saggin P. The sulcus deepening trochleoplasty–the Lyon’s procedure. Int Orthop 2010;34:311–6. [20] Schöttle P, Schmeling A, Romero J, Weiler A. Anatomical reconstruction of the medial patellofemoral ligament using a free gracilis autograft. Arch Orthop Trauma Surg 2009;129:305–9. [21] Christiansen SE, Jacobsen BW, Lund B, Lind M. Reconstruction of the medial patellofemoral ligament with gracilis tendon autograft in transverse patellar drill holes. Arthroscopy 2008;24:82–7. [22] Stephen JM, Kittl C, Williams A, Zaffagnini S, Marcheggiani Muccioli GM, Fink C, et al. Effect of medial patellofemoral ligament reconstruction method on patellofemoral contact pressures and kinematics. Am J Sports Med 2016;44:1186–94. [23] Verdonk R, Jansegers E, Stuyts B. Trochleoplasty in dysplastic knee trochlea. Knee Surg Sports Traumatol Arthrosc 2005;13:529–33. [24] Ntagiopoulos PG, Dejour D. Current concepts on trochleoplasty procedures for the surgical treatment of trochlear dysplasia. Knee Surg Sports Traumatol Arthrosc 2014;22:2531–9. [25] Dejour D, Byn P, Ntagiopoulos PG. The Lyon’s sulcus-deepening trochleoplasty in previous unsuccessful patellofemoral surgery. Int Orthop 2013;37: 433–9. [26] Walker T, Perkinson B, Mihalko WM. Patellofemoral arthroplasty: the other unicompartmental knee replacement. J Bone Joint Surg 2012;94: 1712–20. [27] Mofidi A, Veravalli K, Jinnah RH, Poehling GG. Association and impact of patellofemoral dysplasia on patellofemoral arthropathy and arthroplasty. Knee 2014;21:509–13. [28] Van Haver A, De Roo K, De Beule M, Labey L, De Baets P, Dejour D, et al. The effect of trochlear dysplasia on patellofemoral biomechanics: a cadaveric study with simulated trochlear deformities. Am J Sports Med 2015 [03635465155 72143]. [29] Fosco M, Dagher E. Proposal of a therapeutic protocol for selected patients with patellofemoral knee osteoarthritis: arthroscopic lateral retinacular release followed by viscosupplementation. Musculoskelet Surg 2016:1–8. [30] Becker R, Röpke M, Krull A, Musahl V, Nebelung W. Surgical treatment of isolated patellofemoral osteoarthritis. Clin Orthop Relat Res 2008;466:443–9.
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Original article
Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes S. Otsuki ∗ , Y. Okamoto , T. Murakami , K. Nakagawa , N. Okuno , H. Wakama , M. Neo Department of orthopedic surgery, Osaka medical college, 2-7 Daigakumachi Takatsuki, 569-8686 Osaka, Japan
a r t i c l e
i n f o
Article history: Received 18 August 2017 Accepted 3 January 2018 Keywords: Patellar instability Patella alta Middle age Trochleoplasty
a b s t r a c t Introduction: Although several surgical treatments for patellar instability with patella alta have been reported, the clinical outcomes and optimal surgical procedures for patellar instability with patella alta in middle-aged patients are still controversial. We hypothesized that optimal surgical procedures for patellar instability with patella alta in middle-aged patients may induce good clinical outcomes with better patellofemoral geometry. Materials and methods: Twelve middle-aged patients with a mean age of 44 years (range: 40–55 years), who presented with patellar instability and patella alta, were treated with a combination of several surgeries, such as medial patellofemoral ligament (MPFL) reconstruction, trochleoplasty, lateral release, and three-dimensional transfer of the tibial tuberosity, based on a surgical algorithm. Patellar position and clinical outcomes were evaluated postoperatively. The mean follow-up time was 41.5 months (range: 24–72 months). Results: Patellar position altered from 1.31 (1.21–1.53) preoperatively to 0.88 (0.69–1.06) postoperatively on the Caton-Deschamps Index (p < 0.01). The tibial tuberosity–trochlear groove (TT-TG) distance altered from 21.8 mm (20.1–25.8 mm) to 10.3 mm (5.1–14.7 mm), and patellar tilt ranged from 28.1◦ (21–40◦ ) to 14.6◦ (5–28◦ ), respectively (p < 0.01). Clinical outcomes on the Lysholm and Kujala scales improved from 43.1 and 38.4 to 86.7 and 78.3, respectively, at final follow-up (p < 0.01). Surgical treatment that included trochleoplasty resulted in better outcomes than other surgical combinations without trochleoplasty (p < 0.05). Sulcus angle and postoperative patellar tilt improved more in those who underwent trochleoplasty than in those who did not (p < 0.05). Discussion: Surgical treatment for patellar instability with patella alta in middle-aged patients resulted in improved clinical outcomes. In particular, a combination surgery including trochleoplasty resulted in the greatest improvement in case of severe trochlear dysplasia. Level of evidence: IV. Retrospective case series study. © 2018 Elsevier Masson SAS. All rights reserved.
1. Introduction Patellar instability after recurrent patellar dislocation is associated with patellofemoral dysplasia, such as patella alta, trochlear dysplasia, patellar dysplasia, and original malalignment [1,2]. Patellar instability and patellar dislocation occur most frequently in teenagers, and numerous surgical techniques have been described, including trochleoplasty, medial patellofemoral ligament (MPFL) reconstruction, and transfer of the tibial tuberosity [3]. Trochleoplasty is an established and accepted technique for the treatment of patellar instability to address a shallow or
∗ Corresponding author. E-mail address: [email protected] (S. Otsuki).
absent trochlear groove [4]. Trochleoplasty was first described by Masse, who remodeled the trochlear groove [5], with good clinical outcomes [6–9]. If patellar stability is not restored, it can lead to articular cartilage injury, pain, decreased activity, and patellofemoral osteoarthritis (OA) [10]. MPFL reconstruction is another surgical approach to address patellofemoral instability. With regard to the factors that impact clinical outcomes following MPFL reconstruction, Enderlein et al. reported that age greater than 30, obesity, cartilage injury, and female sex are predictors of poor subjective outcome following surgery [11]. In previous studies, we have treated patellar instability with patella alta, using a three-dimensional (3D) transfer of the tibial tuberosity [12] and have shown that the clinical outcomes depend on the age of the patient at the time of surgery, which also correlates with cartilage damage [13]. The main problem with
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Please cite this article in press as: Otsuki S, et al. Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes. Orthop Traumatol Surg Res (2017), https://doi.org/10.1016/j.otsr.2018.01.003
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Table 1 Patient characteristics and radiological parameters. Patients (M/F) Age (y.o.) BMI (kg/m2 ) FTA (◦ ) K/L grade Patellofemoral OA Follow-up (months)
12 (2/10) 44 (40–55) 24.4 (19.6–29.8) 175 (169–180) I; 2, II; 7, III; 3 I; 1, II; 5, III; 5, IV: 1 41.5 (24–72)
BMI: body mass index; K/L: Kellgren-Lawrence; OA: osteoarthritis.
patellar instability during middle age is that most patients have already progressed to the point of secondary osteoarthritic changes, including osteophyte formation and cartilage erosion. These aging and osteoarthritic changes may prevent better patellofemoral congruity after general patellofemoral reconstruction surgery. Moreover, an additional option for trochleoplasty might be needed for improving patellofemoral geometry. Although several surgical treatments for patellar instability have been reported, the optimal clinical approach for patellar instability with patella alta in middle-aged patients is still controversial. The purpose of this study was to clarify the optimal surgical approach for patellar instability with patella alta based on a surgical algorithm and to assess the effect of trochleoplasty in middle-aged patients. The hypothesis was that optimal surgical procedures for patellar instability with patella alta in middle-aged patients may induce good clinical outcomes with better patellofemoral geometry. 2. Materials and methods 2.1. Enrollment From 2008 to 2015, we operated on 42 patients (47 knees) for recurrent patellar instability at our institution. The inclusion criteria for this study were patellar instability with patella alta and age from 40 to 70 years. We excluded 28 patients (32 knees) who were younger than 40, one patient (one knee) older than 70, and 2 patients (2 knees) who were older than 40, but did not have patella alta. Ultimately, 12 patients (2 males and 10 females) were analyzed in this study. The mean age was 44 years (40–55 years) and the mean body mass index (BMI) was 24.4 kg/m2 (19.6–29.8 kg/m2 ). The mean femorotibial angle (FTA) was 175◦ (169–180◦ ). On the Kellgren-Lawrence Scale, 2 patients had grade I knee OA, 7 had grade II, and 3 had grade III OA. Meanwhile, 1 patient had stage I patellofemoral OA, 5 had stage II, 5 had stage III, and 1 had stage IV OA, based on Iwano’s classification [14]. The mean time to final follow-up was 41.5 months (24–72 months) (Table 1). This study was performed in accordance with a protocol approved by the institutional review board of Osaka Medical College (no. 1291).
2.3. Surgical technique Three-dimensional transfer of the tibial tuberosity has been described previously [12]. Briefly, an anteromedial to posterolateral osteotomy of the tibial tuberosity was performed and the tibial tuberosity was transferred to an anteromedial and distal position based on the degree of patella alta and TT-TG distance to restore normal patellar position. Trochleoplasty was performed in two ways. Sulcus-deepening osteotomy was performed when the articular cartilage had an International Cartilage Repair Society (ICRS) cartilage grade lower than grade II [19]. When the cartilage had already eroded at the patellofemoral joint, a v-shaped sulcus-deepening osteotomy was performed. After removing the osteophytes, the location and depth of the sulcus-deepening osteotomy was determined according to (a) the length of the lateral facet and (b) the cleft of the patella, respectively (Fig. 1A and B). After creating the lateral facet, the new joint surface was coated with bone wax to prevent bleeding and arthrofibrosis. When the cartilage was preserved at the medial facet (Fig. 1C), sulcus deepening was performed according to Dejour’s procedure [19] and fixed with fiber wire (Fig. 1D). Postoperative X-ray was shown in Fig. 1D. MPFL reconstruction was performed using the gracilis tendon [20,21]. The tendon was fitted with No. 0 FiberWire non-absorbable suture baseball stitches (Arthrex, Naples, FL, US) at each end. After making a bone tunnel on the femoral side, the gracilis was fixed to the lateral femoral cortex with an Endobutton CL (Smith & Nephew, Memphis, TN, US). Subsequently, it was fixed to 2 holes in the patella, using 4.75 mm SwiveLock (Arthrex) with a tension of 10 N, using a tension meter at 30◦ of knee flexion based on biomechanical analysis [22]. The surgical procedures for all cases are shown in Table 3. All cases involved 3D transfer of the tibial tuberosity due to patella alta. Five patients had Dejour type A trochlear dysplasia, 2 had type B, 3 had type C, and 2 had type D. Four patients with Dejour type B and D dysplasia were treated with trochleoplasty. Three patients with patellar instability displayed a lateral shift at 60◦ on a skyline view and were treated with MPFL reconstruction. The remaining 9 patients underwent medial plication. Lateral release was performed in all cases. 2.4. Rehabilitation All surgical procedures were allowed the same protocol; Passive ROM exercise was allowed from the first day after surgery. Fifty percent weight-bearing was started 2 weeks after surgery and full weight-bearing was permitted 4 weeks after surgery. 2.5. Assessment method Patellar position and clinical outcomes were compared pre- and postoperatively. Patellar position was measured using the CatonDeschamps Index, TT-TG distance, and patellar tilt, and the clinical outcomes were evaluated using Lysholm and Kujala scores.
2.2. Surgical algorithm for patellar instability with patella alta 2.6. Statistical analysis Surgical treatment was selected based on our algorithm (Table 2). Patellar height was evaluated using the Caton-Deschamps Index [15,16], trochlear dysplasia was classified using the Dejour classification [17], and lateral shift was evaluated on plain radiographs using a skyline view at 30◦ and 60◦ of knee flexion. Malalignment of the patella and lower extremity was evaluated by patellar tilt and tibial tuberosity–trochlear groove (TT-TG) distance with CT scan [16,18]. Based on this composite evaluation, a combination of surgical procedures such as transfer of the tibial tuberosity, MPFL reconstruction, medial plication, release of the lateral retinaculum, and trochleoplasty for sulcus deepening were selected.
Pre- and postoperative results were compared using a paired T-test and JMP Pro software (version 11.2.0, SAS, Cary, NC, US). A comparison of clinical outcomes was performed using the MannWhitney U test. A p-value of < 0.05 was considered statistically significant. 3. Results Postsurgical patellar position was located from 1.31 (1.21–1.53) to 0.88 (0.69–1.06) on the Caton-Deschamps index, with a TT-TG distance of 21.8 mm (20.1–25.8 mm) to 10.3 mm (5.1–14.7 mm),
Please cite this article in press as: Otsuki S, et al. Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes. Orthop Traumatol Surg Res (2017), https://doi.org/10.1016/j.otsr.2018.01.003
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Table 2 Algorism for patellar instability with patella alta. Proximal
Distal
Trochlea dysplasia
Lateral sift
Patella malalignment
Patella alta
Mal-rotation
CD: Caton-Deschamps index; TT-TG: tibial tuberosity–trochlear groove distance; MPFL: medial patellofemoral ligament.
Fig. 1. Surgical procedure for trochleoplasty. A and B. Planning of a v-shaped sulcus-deepening osteotomy. V-shaped osteotomy is planned based on the (a) length and (b) crest of the patella. C and D. V-shaped osteotomy of the femoral trochlea performed at the site of sclerotic bone. After creating the lateral facet, the new joint surface is coated with bone wax. When the cartilage is preserved, especially at the medial facet, sulcus deepening is performed according to Dejour’s procedure and fixed with fiber wire. E and F. Pre- and postoperative X-ray were shown. Table 3 Surgical procedures for all cases. Case
Age, gender
Caton-Deschamps
3D transfer
Dejour
Trochleoplasty
1 2 3 4 5 6 7 8 9 10 11 12
46 F 55 M 43 F 44 F 45 F 40 M 47 F 43 F 43 F 44 F 45 F 46 F
1.24 1.32 1.21 1.35 1.21 1.35 1.35 1.53 1.22 1.28 1.53 1.24
O O O O O O O O O O O O
D D B B C A A C A C A A
O O O O
MPFL
Medial plication
Lateral release
PFOA
O O
O O O O O O O O O O O O
3 4 3 3 2 3 2 2 1 2 2 3
O O O O O O O O O O
3D transfer: three-dimensional transfer of tibial tuberosity; MPFL: medial patellofemoral ligament; PFOA: patellofemoral osteoarthritis.
and 28.1◦ (21–40◦ ) to 14.6◦ (5–28◦ ) of patellar tilt (Table 4, p < 0.01). The mean Lysholm and Kujala scores improved significantly from 43.1 to 86.7, and 38.4 to 78.3, respectively (Fig. 2, p < 0.01). To further assess the surgical factors related to clinical outcomes, we focused on patellar medialization and trochleoplasty. Although there was no significant difference between MPFL reconstruction and plication of the medial retinaculum for medialization, the 4 patients with Dejour type B or D dysplasia, who underwent trochleoplasty, showed significantly greater improvement than the
other 8 patients who did not undergo trochleoplasty (Table 5, p < 0.05). The preoperative sulcus angle in those who underwent trochleoplasty was significantly higher than in those that did not undergo trochleoplasty (Table 6, p = 0.003), but no significant difference was detected postoperatively. Patellar tilt was significantly improved with or without trochleoplasty (p < 0.01). However, postoperative patellar tilt in those who underwent trochleoplasty improved more than the patellar tilt in those who did not undergo trochleoplasty.
Please cite this article in press as: Otsuki S, et al. Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes. Orthop Traumatol Surg Res (2017), https://doi.org/10.1016/j.otsr.2018.01.003
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Fig. 2. Comparison of pre- and postoperative clinical outcomes. With combination surgery, the mean Lysholm and Kujala scores significantly improved from 43.1 to 86.7 and from 38.4 to 78.3, respectively (p < 0.01). Table 4 Changes of patellofemoral geometry.
Patellar position Caton-Deschamps TT-TG Patellar tilt
Preoperative
Final F/U
p-value
1.31 (1.21–1.53) 21.8 (20.1–25.8) 28.1 (21–40)
0.88 (0.69–1.06) 10.3 (5.1–14.7) 14.6 (5–28)
< .01 < .01 < .01
F/U: follow up; TT-TG: tibial tuberosity–trochlear groove distance. Table 5 Effect of patellar medializationand trochleoplasty for clinical outcome. Lysholm
Kujala
Patellar medialization
MPFL
plication
p-value
MPFL
plication
p-value
Preoperative Final F/U Improvement Trochleoplasty Preoperative Final F/U Improvement
39.6 76.9 37.3 + 33.5 86.8 53.3
42.9 85.3 42.4 − 40.9 74.9 34.0
n.s. n.s. n.s.
35.0 84.7 49.7 + 38.8 92 53.3
45.7 90.7 45 − 44.8 82.8 37.4
n.s. n.s. n.s.
.017 n.s. .020
n.s. n.s. .005
Clinical outcome of Lysholm and Kujala scores were compared between MPFL reconstruction and plication of medial retinaculum, and with or without trochleoplasty. MPFL: medial patellofemoral ligament; F/U: follow up. Improvement = Final F/U − Preoperative Score. Table 6 Radiographical changes with trochleoplasty. Trochleoplasty Sulcus angle Preoperative Postoperative Patellar tilt Preoperative Postoperative
+
−
p-value
158.0 ± 6.5 141.5 ± 4.2*
144.3 ± 5.2 144.4 ± 4.5
.003 .31
28.0 ± 6.1 9.0 ± 4.8*
28.2 ± 6.7 17.1± 5.5*
.97 .03
Comparison between pre- and postoperative parameters and significant difference were detected in asterisk (*). * p < 0.01.
4. Discussion The most important finding of this study was that the clinical outcomes for patellar instability with patella alta in middleaged patients significantly improved with surgical treatment. In particular, a combination of surgical procedures including trochleoplasty for Dejour type B and D trochlear dysplasia improved patellofemoral geometry, with good clinical outcomes.
With regard to the clinical outcomes of sulcus-deepening trochleoplasty, Ntagiopoulos et al. reported satisfactory restoration of patellar stability and improvement of knee scores, with no complications due to subsequent arthritis at midterm follow-up [6]. Likewise, several reports of sulcus-deepening trochleoplasty have shown good clinical outcomes with long-term results [7–9]. However, sulcus-deepening trochleoplasty requires careful attention to detail [23]. Patellofemoral arthritis, skeletal immaturity, and isolated patellofemoral pain are contra-indications for trochleoplasty [24]. Although trochleoplasty is not indicated for patellofemoral arthritis [19] and arthrofibrosis after trochleoplasty has been reported [23], trochleoplasty can permanently restore patellofemoral stability [4]. In the present series, we performed a combination surgery based on a surgical algorithm, which included trochleoplasty for Dejour type B and D trochlear dysplasia [16]. The first of these patients experienced a contracture caused from the two weeks’ immobilization and performed manipulation; otherwise, there were no limitations in knee range of motion. From the second patient onward, rehabilitation started strictly on postoperative day 1. Physicians should consider a strong fixation procedure such as trochleoplasty in combination with MPFL reconstruction to achieve patellar stability with early exercise [25]. Patellofemoral OA is a relatively common condition that affects up to 24% of women and 11% of men older than 55 years who have symptomatic OA of the knee [26]. Isolated patellofemoral arthritis is highly associated with patella alta and trochlear dysplasia [27]. Van Haver et al. investigated trochlear dysplasia and patellofemoral biomechanics in a cadaveric study, and reported that the relationship between the shape of the trochlea and patellofemoral biomechanics can provide insight into the short-term effects (maltracking, increased pressure, and instability) and long-term effects (OA) of different types of trochlear dysplasia [28]. The reported surgical options for patellofemoral OA in middle-aged patients include patellectomy [11,12], lateral retinacular release [29], lateral patellar facetectomy, or a combination of these [30]. If patients with patellar instability and patella alta undergo these surgeries, patellar instability may be accelerated by of the loss of patellofemoral congruity. Establishing better patellofemoral congruity might induce better clinical outcomes and has potential of cartilage remodeling after surgery. This study has several limitations. It is a retrospective study with a short-term follow-up period involving a very small number of heterogeneous patients because most of the patients had received surgical treatment within teenager and middle-aged
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Please cite this article in press as: Otsuki S, et al. Patellofemoral reconstruction for patellar instability with patella alta in middle-aged patients: Clinical outcomes. Orthop Traumatol Surg Res (2017), https://doi.org/10.1016/j.otsr.2018.01.003