The Journal of Arthroplasty 29 (2014) 2146–2149

Contents lists available at ScienceDirect

The Journal of Arthroplasty journal homepage: www.arthroplastyjournal.org

Partial Lateral Patellar Facetectomy as an Alternative to Lateral Release in Total Knee Arthroplasty (TKA) Dror Lakstein, MD a, b, Muhammad Naser, MD a, Eliyahu Adar, MD a, Ehud Atoun, MD c, d, Alexander Edelman, MD a, David Hendel, MD a, b a b c d

Orthopaedic Department, E. Wolfson Medical Center, Holon, Israel Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel Orthopaedic Department, Barzilai Medical Center, Ashkelon, Israel Faculty of Medicine, Ben-Gurion University, Beer-Sheva, Israel

a r t i c l e

i n f o

Article history: Received 10 January 2014 Accepted 24 June 2014 Keywords: total knee arthroplasty patellar tracking maltracking lateral release facetectomy

a b s t r a c t This study presents the selective use of partial patellar lateral facetectomy for maltracking during primary TKA, as an alternative to lateral release. Twenty three partial facetectomies were performed out of 191 TKAs (12%). Balanced tracking was achieved in 22 knees. At follow-up 2 patients had persistent anterior knee pain. Mean Knee Society score (KSS) was 94 and mean functional KSS was 86. Mean patellar score was 28. Patellar tilt angles were within 2 degrees in all but one knee. Patellar translation was within 2 mm in all cases. No complications were recorded. A control group of 46 matched patients had similar functional and radiographic results. If tracking is not satisfactory at the conclusion of TKA, our method of choice would be partial lateral facetectomy. © 2014 Elsevier Inc. All rights reserved.

Patellofemoral pain and instability remain the common postoperative complications after TKA and 8–12% of early revisions are performed because of patellofemoral problems [1–3]. It was demonstrated that even a mild degree of patellar maltracking may be associated with patellar pain and higher degrees may lead to actual instability [4–6]. The best means of dealing with patellar maltracking is by prevention, including proper coronal and rotational alignment of the implants. Nevertheless, between 5 and 52% of cases need surgical management of some extent of maltracking [4,7–14]. When the patella is resurfaced, medial placement of the button may improve tracking. In extreme cases, distal realignment would be necessary. However, the “workhorse” of patellar maltracking management is still the lateral retinacular release. Lateral release may injure the lateral blood supply of the patella, with the medial supply already injured during arthrotomy. It may also leave the joint open. Complications associated with lateral release include avascular necrosis, anterior knee pain, wound healing complications, patellar fractures and patellar loosening. Lateral release was also associated with longer stay in hospital, higher transfusion rates and poorer range of motion [4,10,15]. Lateral patellar decompression has been sporadically described in the context of the management of patellofemoral arthrosis, with the

The Conflict of Interest statement associated with this article can be found at http:// dx.doi.org/10.1016/j.arth.2014.06.013. Reprint requests: Dror Lakstein, MD, Orthopaedic Department, E. Wolfson Medical Center, POB 5, Holon, Israel, 58100. http://dx.doi.org/10.1016/j.arth.2014.06.013 0883-5403/© 2014 Elsevier Inc. All rights reserved.

purpose of limiting pain generated by the contact of the lateral patellar facet and the lateral femoral trochlea [16–18]. During patellar resurfacing, decompression or beveling of the lateral remainder of the patella may be performed in order to prevent pain. We present our experience with a technique of managing unresurfaced patellar maltracking during TKA as an alternative to lateral release. Partial lateral facetectomy of the patella achieves bony decompression and effective retinacular lengthening while sparing the vascular supply of the patella. The objectives of this study were to examine the efficiency of the technique in achieving good tracking, the short term functional outcomes and the rate of complications related to the technique. Patients and Methods 191 primary total knee arthroplasties were performed in our institution during 2010 and 2011. Revisions and difficult primaries in which constrained implants were used were not included. The study group included all patients in which at the conclusion of surgery patellar tracking was not satisfactory. Twenty three partial facetectomies (12%) were performed in 22 patients (16 females and 6 males). Mean age was 70 (range, 50–83). Twenty one knees had varus or neutral alignment preoperatively and 2 had valgus knees. Indication for surgery was osteoarthritis in 21 patients and rheumatoid arthritis in a single patient. One patient died a few months after surgery and one patient had a stroke leaving her in a vegetative state. One patient underwent a later patellar resurfacing. All other 19 patients

D. Lakstein et al. / The Journal of Arthroplasty 29 (2014) 2146–2149

(20 knees) were contacted and showed up at our clinic for clinical and radiographic follow-up. Mean follow-up was 33 months (range, 17–45). Forty six matched patients were identified from the 191 patients to act as a control group. The matched group had undergone primary TKA with no need to correct tracking. Two control patients were blindly and individually matched to a study patient on the basis of gender and age. Mean follow-up was 38 months (range, 30–53). Seven patients were lost to follow-up and one patient underwent a revision due to unresolving pain 2 years postoperatively. Details of the two groups are summarized in Table 1. The study was approved by the institutional ethics committee, and all patients were consented before evaluation. The primary endpoint of the study was the intraoperative correction of maltracking, obviating the need for lateral release, as judged by the surgeon using the “no thumb” technique. Intraoperative maltracking was classified as tilting, subluxation or dislocation [5,11]. Functional outcome was evaluated using the Knee Society Score and the Feller patellar score [19,20]. Radiographic evaluation included routine standing AP and lateral views of the knee and a 30° skyline view (Fig. 1) [21]. Tracking was assessed by measuring patellar tilt and patellar translation on the skyline view [22,23]. Patellar maltracking was defined as patellar tilt of N 5° or displacement N5 mm [11]. Complications were recorded. Surgical Technique All surgeries were performed by 3 of the authors (DH, AE, DL) through a medial parapatellar approach using posterior stabilized Nexgen mobile bearing implants (Zimmer, Warsaw, Indiana). We do not resurface the patella. Tourniquets were used in all cases. The femur was rotated to be parallel to the interepicodylar axis as verified by Whiteside's AP axis. The tibia was rotated toward the medial third of the tibial tuberosity. Patellar tracking was assessed with the trial components in and further adjustment of tibial rotation was performed as required. After cementation of the implants, tourniquet release, resection of patellar osteophytes and determination of appropriate polyethylene thickness, patellar tracking was assessed again, using the “rule of no thumb”. Tracking was considered adequate when the medial facet and the medial femoral trochlea were in congruent contact throughout the range of motion. Patellar tilt or shift was considered as maltracking. When tracking was not adequate, a partial facetectomy was performed as follows: the patella is everted and a longitudinal line is

Table 1 Patient Demographics, Clinical Scores, Tilt Angles and Lateral Translations. Facetectomy Number of knees 23 Gender (F:M) 16:7 Age: mean (range) years 70 (50–83) Deformity Varus/neutral 21 Valgus 2 Lost to follow-up 3 Follow-up: mean (range) months 33 (17–45) Clinical scores Knee Society Score – pain: mean (range) 94 (68–100) Knee Society Score – function: 86 (55–100) mean (range) Patellar Score: mean (range) 28 (20–30) Tilt angles b2° 19 3–7° 0 N8° 1 Patellar lateral translation 20 0–2 mm 0 2–5 mm N5 mm 0

Fig. 1. A skyline view after partial patellar facetectomy showing perfect alignment of the patella with no tilt or translation.

marked along the articular surface of the lateral facet, parallel to the patellar ridge and leaving between a third and a half of the facet lateral to it (Fig. 2A and B). We tend to cut more patella when the lateral facet is elongated and deformed and be more conservative when the patella maintains its structure. Still, one must avoid cutting more than half of the facet in order to prevent paradoxical medial tilt and insufficient contact area. Using an oscillating saw the bone is cut sagittally along the marked line, cutting the lateral part of the patella out (Fig. 2C). This act should be done cautiously, avoiding damage to the soft tissue and cutting only bone. The cut fragment is carefully separated from the overlying retinaculum with a sharp scalpel blade. Using the saw, we perform a second oblique cut, beveling the remainder of the lateral facet and enhancing congruency (Fig. 2D and E). After completing the bony cuts we bring the knee to full flexion a few times in order to stretch the released tissue. The overall effect of this maneuver includes bony decompression of the lateral patellofemoral articulation and functional elongation of the lateral retinaculum. Patellar tracking is assessed again and if still unsatisfactory we perform a staged lateral retinacular release. Continuous variables were compared using the t-test for independent samples. Discrete variables were analyzed with the χ 2 test. Differences of P b 0.05 were considered to be statistically significant.

Results

Control

P Value

46 32:14 71 (54–80)

.64

44 2 8 38 (30–53)

.59 0.03

92 (45–100) 87 (55–100)

.76 .60

27 (18–30)

.47

36 1 1 37 1

.69

0

2147

.46

.46

Intraoperatively, in 21 cases the degree of maltracking was tilt and in 2 cases subluxation of the patella. There were no actual dislocations. The technique was efficient in achieving central balanced tracking of the patella throughout the range of motion in 22 cases (Fig. 3). In one patient maltracking was still noted and a lateral release was performed. There were no intraoperative complications related to the technique. Postoperatively there were no wound healing problems, infections, patellar fractures or radiological finding of patellar avascular necrosis. Two patients complained of persistent anterior knee pain. One of them underwent a reoperation 11 months after the TKA with liner exchange and patellar resurfacing. During surgery patellar tracking appeared perfect and after surgery anterior knee pain persisted. The second patient who had both lateral facetectomy and lateral release in the index surgery had substantial lateral patellar tilt but felt that the pain was not bad enough for him to undergo further surgery. One patient required manipulation under anesthesia due to stiffness. At last follow-up, mean Knee Society score (KSS) was 94 (range, 68–100) and mean functional KSS was 86 (range, 55–100). Scores

2148

D. Lakstein et al. / The Journal of Arthroplasty 29 (2014) 2146–2149

Fig. 2. (A and B) The sagittal cut, taking out the lateral ½–⅓ of the lateral facet. (C) The lateral part of the facet was cut out with an oscillating saw. (D and E) The second oblique cut, beveling the facet and improving congruency.

were excellent or good in 18 patients (19 knees) and fair in one patient. Mean patellar score was 28 (range, 20–30). Postoperative patellar lateral tilt angles as measured in skyline radiographs taken at last follow-up were within 0–1° in 17 knees and 2° in 2 knees. In one patient a tilt angle of 10° was measured. Patellar translation was within 2 mm in all cases. There were no significant differences between the study group and the matched control group regarding KSS, functional KSS, patellar scores, tilt angles or patellar translation. Four patients in the control group had persistent anterior knee pain. Discussion This study presents the selective use of partial patellar lateral facetectomy for the management of patellar maltracking during primary TKA. Facetectomies were performed with the same indications for which a lateral release would have been performed by most surgeons, and when tracking was satisfactory the patella was not cut, regardless of preoperative complaints or patellar deformity. The technique prevented the need for lateral release in 22 out of 23 knees and showed good functional and radiographic results with no complications related to the technique. In particular, patellar scores and the rate of anterior knee pain were as good as in patients who had good intraoperative tracking. This study has several limitations. First, this is a small case series with no control group. However, the results of 22/23 success in obviating the need for lateral release are convincing. Second, the intraoperative assessment of patellar tracking, decision to address maltracking and assessment of performance are all subjective, based on the no thumb technique. Yet, this assessment is not less subjective when deciding to perform a lateral release. Tilt angles and translations were measured postoperatively and were satisfactory in all but one patient. Lateral release is the gold standard for managing patellar maltracking during TKA. Different techniques have been described for releasing the retinaculum. Some authors recommended on a staged release with conservation of the synovial lining of the joint, thus lowering the risk of

injury to the vascular supply of the patella and avoiding leaving the joint open [7,11]. Release has been reported to achieve good tracking intraoperatively, and in most cases of staged release only a partial release was necessary. However, in radiographic follow-up, up to 25% of patients still show signs of maltracking [7,11–13]. The indication to perform a lateral release is not always clear cut. Different authors reported on varying rates of performing release, between 5% and 52% [4,7–14]. In our study we performed a facetectomy on 12% of knees. The difference between surgeons is derived from the surgical technique, mainly the attention given to the rotational alignment of the implants [24], to implants design, but also to different thresholds for performing release. Some authors suggested that the no thumb technique overestimates the true necessity for release and recommended using the towel clip method [11,13]. On the radical side, Zha et al advocated doing a release to all patients [25]. We believe that using a simple technique for lateral decompression with less potential for complications may enable surgeons to be more liberal with fine adjustments of tracking. Lateral release has been associated with some complications. Injury to the superolateral geniculate vessels may be responsible for some of these complications. It must be remembered that the medial blood supply has already been damaged during arthrotomy. As high as 56% “cold patellae” were demonstrated in bone scans after lateral release [26]. However, the clinical significance of devascularization is controversial. Some authors reported on higher rates of anterior knee pain, patellar fractures, stress fractures and loosening [7,14,15,27]. Other studies found no increase in patellar fracture or loosening rates after lateral release [10,27,28]. Vascular injury and subcutaneous hematoma over the unclosed joint may account for the higher rates of wound discoloration, healing problems and infections [14,28,29]. Others found the same rates of infection with and without release [10]. Symptomatic clicking or pain due to the soft tissue defect left at the released retinaculum was also reported [30]. In our small series of lateral facetectomies, no complications related to the technique were noted. Other larger series describing lateral facetectomy, either isolated or during TKA, reported no patellar fractures or wound infections [16–18].

D. Lakstein et al. / The Journal of Arthroplasty 29 (2014) 2146–2149

2149

release, is simple, efficient and safe with potentially less complications. When tracking is not satisfactory, our method of choice for that purpose would be a partial lateral facetectomy. References

Fig. 3. (A) A preoperative skyline view showing an elongated lateral facet. (B) Post facetectomy, the patella is well seated in the trochlear groove.

Lateral bony decompression of the patella has been discussed in a few studies. It was demonstrated that partial lateral facetectomy through a lateral arthrotomy, with or without other realignment measures is of benefit in cases of isolated patellofemoral arthrosis [17,18]. When resurfacing the patella, it was advised to resect the remaining bone lateral to the button in order to prevent painful contact between the patella and the femoral component [31,32]. Zhang et al reported on the use of nonselective lateral facetectomy of the unresurfaced patella in TKA in order to relieve anterior knee pain and recommended the use of the technique in all patients [16]. Interestingly, in his controlled study, lateral release was necessary in 19% of patients without facetectomy and none of the patients who had a facetectomy. This is consistent with our findings. The only report of lateral facetectomy on the unresurfaced patella with the intention to improve tracking was by Wachtl et al [33], who recommended performing the facetectomy routinely, at the end of exposing and before replacing the knee. On the contrary, we believe that the decision that a lateral decompression is required should be selective and taken at the conclusion of surgery with the implants in place, including the appropriate size polyethylene, and after deflating the tourniquet. Conclusion Performing a lateral patellar facetectomy for the management of patellar maltracking at the end of TKA, with the same selective indications commonly used to judge the need for lateral retinacular

1. Fehring TK, Odum S, Griffin WL, et al. Early failures in total knee arthroplasty. Clin Orthop Relat Res 2001;392:315. 2. Sharkey PF, Hozack WJ, Rothman RH, et al. Insall Award paper. Why are total knee arthroplasties failing today? Clin Orthop Relat Res 2002;404:7. 3. Furnes O, Espehaug B, Lie SA, et al. Early failures among 7,174 primary total knee replacements: a follow-up study from the Norwegian Arthroplasty Register 1994– 2000. Acta Orthop Scand 2002;73(2):117. 4. Rand JA. Extensor mechanism complications following total knee arthroplasty. JBJS-A; 2004 2062. 5. Berger RA, Crossett LS, Jacobs JJ, et al. Malrotation causing patellofemoral complications after total knee arthroplasty. Clin Orthop Relat Res 1998:144. 6. Lakstein D, Zarrabian M, Kosashvili Y, et al. Revision total knee arthroplasty for component malrotation is highly beneficial: a case control study. J Arthroplasty 2010:1047. 7. Strachan RK, Merican AM, Devadasan B, et al. A technique of staged lateral release to correct patellar tracking in total knee arthroplasty. J Arthroplasty 2009;24(5): 735 [May 20]. 8. Hofmann AA, Tkach TK, Evanich CJ, et al. Patellar component medialization in total knee arthroplasty. J Arthroplasty 1997;12(2):155. 9. Cinotti G, Ripani FR, Sessa P, et al. Combining different rotational alignment axes with navigation may reduce the need for lateral retinacular release in total knee arthroplasty. Int Orthop 2012;36(8):1595. 10. Molyneux S, Brenkel I. Predictors and outcomes of lateral release in total knee arthroplasty: a cohort study of 1859 knees. Knee 2012;19(5):688. 11. Maniar RN, Singhi T, Rathi SS, et al. Surgical technique: lateral retinaculum release in knee arthroplasty using a stepwise, outside-in technique. Clin Orthop Relat Res 2012;470(10):2854. 12. Laskin RS. Lateral release rates after total knee arthroplasty. Clin Orthop Relat Res 2001;392:88. 13. Archibeck MJ, Camarata D, Trauger J, et al. Indications for lateral retinacular release in total knee replacement. Clin Orthop 2003;414:157. 14. Weber AB, Worland RL, Jessup DE, et al. The consequences of lateral release in total knee replacement: a review of over 1000 knees with follow up between 5 and 11 years. Knee 2003;10:187. 15. Ritter MA, Pierce MJ, Zhou H, et al. Patellar complications (total knee arthroplasty). Effect of lateral release and thickness. Clin Orthop Relat Res 1999;367:149. 16. Zhang LZ, Zhang XL, Jiang Y, et al. Lateral patellar facetectomy had improved clinical results in patients with patellar-retaining total knee arthroplasty. J Arthroplasty 2012;27(8):1442. 17. Montserrat F, Alentorn-Geli E, León V, et al. Treatment of isolated patellofemoral osteoarthritis with lateral facetectomy plus Insall's realignment procedure: longterm follow-up. Knee Surg Sports Traumatol Arthrosc 2013;21(11):2572. 18. Yercan HS, Ait Si Selmi T, Neyret P. The treatment of patellofemoral osteoarthritis with partial lateral facetectomy. Clin Orthop Relat Res 2005(436):14. 19. Noble PC, Scuderi GR, Brekke AC, et al. Development of a new Knee Society scoring system. Clin Orthop Relat Res 2012;470(1):20. http://dx.doi.org/10.1007/s11999-011-2152-z. 20. Feller JA, Bartlett RJ, Lang DM. Patellar resurfacing versus retention in total knee arthroplasty. J Bone Joint Surg (Br) 1996;78(2):226. 21. Laurin CA, Levesque HP, Dussault R, et al. The abnormal lateral patellofemoral angle: a diagnostic roentgenographic sign of recurrent patellar subluxation. J Bone Joint Surg Am 1978;60:55. 22. Gomes LS, Bechtold JE, Gustilo RB. Patellar prosthesis positioning in total knee arthroplasty. A roentgenographic study. Clin Orthop Relat Res 1988;236:72. 23. Bindelglass DF, Cohen JL, Dorr LD. Patellar tilt and subluxation in total knee arthroplasty. Relationship to pain, fixation, and design. Clin Orthop Relat Res 1993;286:103. 24. Newbern DG, Faris PM, Ritter MA, et al. A clinical comparison of patellar tracking using the transepicondylar axis and the posterior condylar axis. J Arthroplasty 2006;21(8):1141. 25. Zha GC, Sun JY, Dong SJ. Less anterior knee pain with a routine lateral release in total knee arthroplasty without patellar resurfacing: a prospective, randomized study. Knee Surg Sports Traumatol Arthrosc 2014;22(3):517. 26. Scuderi G, Scharf SC, Meltzer LP, et al. The relationship of lateral releases to patella viability in total knee arthroplasty. J Arthroplasty 1987;2(3):209. 27. Ritter MA, Herbst SA, Keating EM, et al. Patellofemoral complications following total knee arthroplasty. Effect of a lateral release and sacrifice of the superior lateral geniculate artery. J Arthroplasty 1996;11(4):368. 28. Kusuma SK, Puri N, Lotke PA. Lateral retinacular release during primary total knee arthroplasty: effect on outcomes and complications. J Arthroplasty 2009;24(3):383. 29. Johnson DP, Eastwood DM. Lateral patellar release in knee arthroplasty. Effect on wound healing. J Arthroplasty 1992;7(Suppl):427. 30. Engh GA, Holt BT, Parks NL. A midvastus muscle splitting approach for total knee arthroplasty. J Arthroplasty 1997;12:322. 31. Doerr TE, Eckhoff DG. Lateral patellar burnishing in total knee arthroplasty following medialization of the patellar button. J Arthroplasty 1995;10:540. 32. Marmor L. Technique for patellar resurfacing in total knee arthroplasty. Clin Orthop Relat Res 1988(230):166. 33. Wachtl SW, Jakob RP. Patella osteotomy for lateral retinaculum decompression in total knee arthroplasty. Acta Orthop Scand 2000;71(5):522.

Partial lateral patellar facetectomy as an alternative to lateral release in Total Knee Arthroplasty (TKA).

This study presents the selective use of partial patellar lateral facetectomy for maltracking during primary TKA, as an alternative to lateral release...
543KB Sizes 0 Downloads 4 Views