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Editorial Commentary: Does Patellofemoral Degenerative Progression After Open-Wedge High Tibial Osteotomy Adversely Affect Clinical Outcomes?
Editorial Commentary: Does Patellofemoral Degenerative Progression After Open-Wedge High Tibial Osteotomy Adversely Affect Clinical Outcomes? Kenichi Goshima, M.D., Ph.D.
Abstract: Open-wedge high tibial osteotomy causes deterioration of the patellofemoral cartilage status. However, whether patellofemoral degenerative progression adversely affects clinical outcomes remains unclear, thereby necessitating a comprehensive long-term follow-up study.
See related article on page 1703
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ately, open-wedge high tibial osteotomy (OWHTO) has become a standard treatment option for medial compartment osteoarthritis (OA).1,2 However, despite the favorable clinical outcomes associated with OWHTO, patellofemoral complications, including descent of the patellar height and patellofemoral malalignment, are usually reported after OWHTO.3 Experimental biomechanical studies have established a correlation between OWHTO and a marked elevation in patellofemoral contact pressure, a phenomenon that exacerbates the risk of patellofemoral OA and anterior knee pain.4,5 Some recent clinical studies have reported the progression of patellofemoral cartilage degeneration on second-look arthroscopy after OWHTO.3,6,7 Nevertheless, whether patellofemoral degenerative progression adversely affects clinical outcomes remains unclear. The study by Lee, So, Jung, Kim, Lee, and Wang,8 “Predictive Factors for Patellofemoral Degenerative Progression After Opening-Wedge High Tibial Osteotomy,” retrospectively assessed the risk factors for
Toyama, Japan The author reports no conflicts of interest in the authorship and publication of this article. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Ó 2019 by the Arthroscopy Association of North America 0749-8063/19321/$36.00 https://doi.org/10.1016/j.arthro.2019.03.016
patellofemoral degenerative progression after OWHTO and examined the impact of patellofemoral degeneration on patient-reported outcomes, including the Kujala score and Knee Injury and Osteoarthritis Outcome Score. The authors examined 94 knees and concluded that postoperative overcorrected mechanical alignment correlates with patellofemoral degenerative progression after OWHTO and that patients with patellofemoral degenerative progression exhibit inferior patient-reported outcomes. Prior studies have shown that cartilage degeneration in the patellofemoral joint progressed in 33%e45% of patients at the time of second-look arthroscopy after OWHTO (the mean interval between initial high tibial osteotomy and second-look arthroscopy was 14e26 months).3,6,7 Likewise, the study of Lee et al.8 reported that 30% of patients exhibited patellofemoral degenerative progression after OWHTO, which could be elucidated by a marked elevation of patellofemoral contact pressure after OWHTO reported in prior biomechanical studies.4,5 Moreover, Lee et al.8 suggested that overcorrection, which indicated a higher correction angle, could induce patellofemoral degenerative progression. Similarly, Tanaka et al.7 reported that cartilage injuries in the patellofemoral joints tended to progress after OWHTO in the knees, with medial open gap 13 mm, or with a change in the medial proximal tibial angle 9 . Javidan et al.5 investigated the impact of OWHTO on the patellofemoral joints in cadaveric knees and reported that the contact pressure
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 35, No 6 (June), 2019: pp 1711-1712
1711
1712
EDITORIAL COMMENTARY
of the patellofemoral joint significantly increased in the knees with a medial opening gap of 10 mm. Hence, I agree with these findings. If the opening gap is 13 mm in planning for OWHTO, another type of surgery should be considered to avoid the early progression of patellofemoral cartilage injuries. However, whether this patellofemoral degenerative progression after OWHTO adversely affects the clinical outcomes remains unclear. In the study by Lee et al.,8 patients with patellofemoral degenerative progression exhibited inferior patient-reported outcomes. Likewise, Kim et al.6 reported postoperative anterior knee pain in 11.4% of patients, which correlated with patellofemoral arthrosis. Conversely, several studies have highlighted that the patellofemoral OA progression after OWHTO did not affect clinical outcomes.3,7,9 In my experience, despite the progression of patellofemoral OA after OWHTO, there are few cases of anterior knee pain.3 I have two reservations about the study of Lee et al.,8 and the conclusions must be interpreted with caution. First, whether only the deterioration of patellofemoral cartilage adversely affects clinical outcomes remains debatable. The study mentions nothing about the prevalence of anterior knee pain and local findings associated with the patellofemoral joint. Moreover, the mean change in the mechanical axis was 14.6 in the patellofemoral degenerative progression group; I believe that this large correction angle caused abnormal joint line obliquity, which could have resulted in the inferior clinical outcomes in the progression group. Akamatsu et al.10 and Schuster et al.11 reported that overcorrected medial proximal tibial angle exerted a negative impact on the clinical outcomes after OWHTO. Second, patients were divided per their patellofemoral degenerative progression from first to second arthroscopy (mean interval: 21.4 months), not at the final follow-up. Thus, the actual status of the patellofemoral joint cartilage at the final follow-up remains unclear, necessitating close follow-up of the long-term effects of patellofemoral degenerative progression. Based on the current literature,3,6-8 it could be concluded that OWHTO causes the progression of the patellofemoral cartilage degeneration; however, the impact of these changes on clinical outcomes remains debatable. In the future, a large-scale long-term followup study is warranted to elucidate this topic.
Acknowledgments The author thanks Enago (www.enago.jp) for the English language review.
References 1. Schuster P, Schulz M, Mayer P, Schlumberger M, Immendoerfer M, Richter J. Open-wedge high tibial osteotomy and combined abrasion/microfracture in severe medial osteoarthritis and varus malalignment: 5-Year results and arthroscopic findings after 2 years. Arthroscopy 2015;31:1279-1288. 2. Goshima K, Sawaguchi T, Sakagoshi D, Shigemoto K, Hatsuchi Y, Akahane M. Age does not affect the clinical and radiological outcomes after open-wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc 2017;25:918-923. 3. Goshima K, Sawaguchi T, Shigemoto K, Iwai S, Nakanishi A, Ueoka K. Patellofemoral osteoarthritis progression and alignment changes after open-wedge high tibial osteotomy do not affect clinical outcomes at midterm follow-up. Arthroscopy 2017;33:1832-1839. 4. Gaasbeek R, Welsing R, Barink M, Verdonschot N, van Kampen A. The influence of open and closed high tibial osteotomy on dynamic patellar tracking: A biomechanical study. Knee Surg Sports Traumatol Arthrosc 2007;15:978-984. 5. Javidan P, Adamson GJ, Miller JR, et al. The effect of medial opening wedge proximal tibial osteotomy on patellofemoral contact. Am J Sports Med 2013;41:80-86. 6. Kim KI, Kim DK, Song SJ, Lee SH, Bae DK. Medial openwedge high tibial osteotomy may adversely affect the patellofemoral joint. Arthroscopy 2017;33:811-816. 7. Tanaka T, Matsushita T, Miyaji N, et al. Deterioration of patellofemoral cartilage status after medial open-wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc 2019;27:1347-1354. 8. Lee S-S, So S-Y, Jung E-Y, Kim H-J, Lee BH, Wang JH. Predictive factors for patellofemoral degenerative progression after opening-wedge high tibial osteotomy. Arthroscopy 2019;35:1703-1710. 9. Lee YS, Lee SB, Oh WS, Kwon YE, Lee BK. Changes in patellofemoral alignment do not cause clinical impact after open-wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc 2016;24:129-133. 10. Akamatsu Y, Kumagai K, Kobayashi H, Tsuji M, Saito T. Effect of increased coronal inclination of the tibial plateau after opening-wedge high tibial osteotomy. Arthroscopy 2018;34:2158-2169. 11. Schuster P, Geßlein M, Schlumberger M, et al. Ten-year results of medial open-wedge high tibial osteotomy and chondral resurfacing in severe medial osteoarthritis and varus malalignment. Am J Sports Med 2018;46: 1362-1370.
Abstract: Open-wedge high tibial osteotomy causes deterioration of the patellofemoral cartilage status. However, whether patellofemoral degenerative progression adversely affects clinical outcomes remains unclear, thereby necessitating a comprehensive long-term follow-up study.
See related article on page 1703
L
ately, open-wedge high tibial osteotomy (OWHTO) has become a standard treatment option for medial compartment osteoarthritis (OA).1,2 However, despite the favorable clinical outcomes associated with OWHTO, patellofemoral complications, including descent of the patellar height and patellofemoral malalignment, are usually reported after OWHTO.3 Experimental biomechanical studies have established a correlation between OWHTO and a marked elevation in patellofemoral contact pressure, a phenomenon that exacerbates the risk of patellofemoral OA and anterior knee pain.4,5 Some recent clinical studies have reported the progression of patellofemoral cartilage degeneration on second-look arthroscopy after OWHTO.3,6,7 Nevertheless, whether patellofemoral degenerative progression adversely affects clinical outcomes remains unclear. The study by Lee, So, Jung, Kim, Lee, and Wang,8 “Predictive Factors for Patellofemoral Degenerative Progression After Opening-Wedge High Tibial Osteotomy,” retrospectively assessed the risk factors for
Toyama, Japan The author reports no conflicts of interest in the authorship and publication of this article. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Ó 2019 by the Arthroscopy Association of North America 0749-8063/19321/$36.00 https://doi.org/10.1016/j.arthro.2019.03.016
patellofemoral degenerative progression after OWHTO and examined the impact of patellofemoral degeneration on patient-reported outcomes, including the Kujala score and Knee Injury and Osteoarthritis Outcome Score. The authors examined 94 knees and concluded that postoperative overcorrected mechanical alignment correlates with patellofemoral degenerative progression after OWHTO and that patients with patellofemoral degenerative progression exhibit inferior patient-reported outcomes. Prior studies have shown that cartilage degeneration in the patellofemoral joint progressed in 33%e45% of patients at the time of second-look arthroscopy after OWHTO (the mean interval between initial high tibial osteotomy and second-look arthroscopy was 14e26 months).3,6,7 Likewise, the study of Lee et al.8 reported that 30% of patients exhibited patellofemoral degenerative progression after OWHTO, which could be elucidated by a marked elevation of patellofemoral contact pressure after OWHTO reported in prior biomechanical studies.4,5 Moreover, Lee et al.8 suggested that overcorrection, which indicated a higher correction angle, could induce patellofemoral degenerative progression. Similarly, Tanaka et al.7 reported that cartilage injuries in the patellofemoral joints tended to progress after OWHTO in the knees, with medial open gap 13 mm, or with a change in the medial proximal tibial angle 9 . Javidan et al.5 investigated the impact of OWHTO on the patellofemoral joints in cadaveric knees and reported that the contact pressure
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 35, No 6 (June), 2019: pp 1711-1712
1711
1712
EDITORIAL COMMENTARY
of the patellofemoral joint significantly increased in the knees with a medial opening gap of 10 mm. Hence, I agree with these findings. If the opening gap is 13 mm in planning for OWHTO, another type of surgery should be considered to avoid the early progression of patellofemoral cartilage injuries. However, whether this patellofemoral degenerative progression after OWHTO adversely affects the clinical outcomes remains unclear. In the study by Lee et al.,8 patients with patellofemoral degenerative progression exhibited inferior patient-reported outcomes. Likewise, Kim et al.6 reported postoperative anterior knee pain in 11.4% of patients, which correlated with patellofemoral arthrosis. Conversely, several studies have highlighted that the patellofemoral OA progression after OWHTO did not affect clinical outcomes.3,7,9 In my experience, despite the progression of patellofemoral OA after OWHTO, there are few cases of anterior knee pain.3 I have two reservations about the study of Lee et al.,8 and the conclusions must be interpreted with caution. First, whether only the deterioration of patellofemoral cartilage adversely affects clinical outcomes remains debatable. The study mentions nothing about the prevalence of anterior knee pain and local findings associated with the patellofemoral joint. Moreover, the mean change in the mechanical axis was 14.6 in the patellofemoral degenerative progression group; I believe that this large correction angle caused abnormal joint line obliquity, which could have resulted in the inferior clinical outcomes in the progression group. Akamatsu et al.10 and Schuster et al.11 reported that overcorrected medial proximal tibial angle exerted a negative impact on the clinical outcomes after OWHTO. Second, patients were divided per their patellofemoral degenerative progression from first to second arthroscopy (mean interval: 21.4 months), not at the final follow-up. Thus, the actual status of the patellofemoral joint cartilage at the final follow-up remains unclear, necessitating close follow-up of the long-term effects of patellofemoral degenerative progression. Based on the current literature,3,6-8 it could be concluded that OWHTO causes the progression of the patellofemoral cartilage degeneration; however, the impact of these changes on clinical outcomes remains debatable. In the future, a large-scale long-term followup study is warranted to elucidate this topic.
Acknowledgments The author thanks Enago (www.enago.jp) for the English language review.
References 1. Schuster P, Schulz M, Mayer P, Schlumberger M, Immendoerfer M, Richter J. Open-wedge high tibial osteotomy and combined abrasion/microfracture in severe medial osteoarthritis and varus malalignment: 5-Year results and arthroscopic findings after 2 years. Arthroscopy 2015;31:1279-1288. 2. Goshima K, Sawaguchi T, Sakagoshi D, Shigemoto K, Hatsuchi Y, Akahane M. Age does not affect the clinical and radiological outcomes after open-wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc 2017;25:918-923. 3. Goshima K, Sawaguchi T, Shigemoto K, Iwai S, Nakanishi A, Ueoka K. Patellofemoral osteoarthritis progression and alignment changes after open-wedge high tibial osteotomy do not affect clinical outcomes at midterm follow-up. Arthroscopy 2017;33:1832-1839. 4. Gaasbeek R, Welsing R, Barink M, Verdonschot N, van Kampen A. The influence of open and closed high tibial osteotomy on dynamic patellar tracking: A biomechanical study. Knee Surg Sports Traumatol Arthrosc 2007;15:978-984. 5. Javidan P, Adamson GJ, Miller JR, et al. The effect of medial opening wedge proximal tibial osteotomy on patellofemoral contact. Am J Sports Med 2013;41:80-86. 6. Kim KI, Kim DK, Song SJ, Lee SH, Bae DK. Medial openwedge high tibial osteotomy may adversely affect the patellofemoral joint. Arthroscopy 2017;33:811-816. 7. Tanaka T, Matsushita T, Miyaji N, et al. Deterioration of patellofemoral cartilage status after medial open-wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc 2019;27:1347-1354. 8. Lee S-S, So S-Y, Jung E-Y, Kim H-J, Lee BH, Wang JH. Predictive factors for patellofemoral degenerative progression after opening-wedge high tibial osteotomy. Arthroscopy 2019;35:1703-1710. 9. Lee YS, Lee SB, Oh WS, Kwon YE, Lee BK. Changes in patellofemoral alignment do not cause clinical impact after open-wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc 2016;24:129-133. 10. Akamatsu Y, Kumagai K, Kobayashi H, Tsuji M, Saito T. Effect of increased coronal inclination of the tibial plateau after opening-wedge high tibial osteotomy. Arthroscopy 2018;34:2158-2169. 11. Schuster P, Geßlein M, Schlumberger M, et al. Ten-year results of medial open-wedge high tibial osteotomy and chondral resurfacing in severe medial osteoarthritis and varus malalignment. Am J Sports Med 2018;46: 1362-1370.