1
|
Hiranaka T. Advantages and limitations of mobile-bearing unicompartmental knee arthroplasty: an overview of the literature. Expert Rev Med Devices 2024:1-14. [PMID: 38873929 DOI: 10.1080/17434440.2024.2367002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 06/07/2024] [Indexed: 06/15/2024]
Abstract
INTRODUCTION Interest in unicompartmental knee arthroplasty (UKA) has recently grown. Mobile bearing UKA, in which the bearing is not fixed but rather perfectly conforms with femoral and tibial components and moves completely passively between the femoral and tibial implant, has now been used for approximately half a century. AREAS COVERED Alongside the recognized advantages of UKA, the mobile-bearing variant benefits from an extremely low rate of polyethylene wear and tolerable minor malalignment. Revision rates for UKA have been reported to exceed those of total knee arthroplasty, but long-term survival rates and outcomes from mobile-bearing UKA have been found to be satisfactory. In addition to the lateral osteoarthritis and loosening, which are main complications of UKA, bearing dislocation is a specific complication of mobile bearing UKA. Fractures and valgus subsidence are more prevalent than in the cementless UKA. While these continue to be features to be addressed, they have been partially solved. EXPERT OPINION Given the manifold benefits of UKA, its application could be extended to a larger patient population. Successful outcomes rely on careful patient selection and the surgeon's extensive familiarity with the procedure. Looking ahead, the incorporation of robotic surgery, already a feature of some fixed-bearing UKAs, might shape the future trajectory of mobile-bearing UKA.
Collapse
Affiliation(s)
- Takafumi Hiranaka
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, Takatsuki, Osaka, Japan
| |
Collapse
|
2
|
Hiranaka T, Kamachi M, Hayashi T, Inoue R, Ogino S, Koide M, Fujishiro T, Okamoto K. Propensity of the tight mid-flexion and loose flexion gap despite the adjustment of extension and flexion gaps in Oxford unicompartmental knee arthroplasty: retrospective study. Arch Orthop Trauma Surg 2024; 144:2783-2788. [PMID: 38761236 DOI: 10.1007/s00402-024-05377-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/07/2024] [Indexed: 05/20/2024]
Abstract
PURPOSE A well-balanced joint gap is necessary in Oxford unicompartmental knee arthroplasty (OUKA) to prevent mobile-bearing dislocation. While the gaps between 20° (extension) and 100° (flexion) are precisely adjusted using the incremental mill system, there has been insufficient evaluation of gaps in other angles. We hypothesized that the gap is not always the same in other angles. This retrospective study aimed to evaluate the gap in full-extension (0°), mid-flexion (60°) and deep flexion (130°) for comparison with those in extension and flexion gaps. METHODS We evaluated 119 knees in 83 patients (51 females, 31 males, aged 71.9 years). The full-extension and mid-flexion gaps were compared with the extension gap, and the deep flexion gap was contrasted with the flexion gap. Each gap was classified into isometric, tight or loose, for evaluation of contributing factors. RESULTS Although the full-extension gap tended to be isometric (45%), the mid-flexion tended to be tight (48%), whereas the deep-flexion was loose in most knees (84%) (P = 0.002). The tight mid-flexion and loose deep flexion gap pattern accounted for 44% of the total knees, especially so with smaller femoral components (P = 0.004). CONCLUSION Our results highlight the propensity of tight mid-flexion and loose flexion gap despite the adjustment of extension and flexion gaps in OUKA. Although the effect of such a minor gap imbalance is still unknown, the pattern was more prevalent in patients with smaller-sized femoral components. Use of a larger femoral component may equalize the gap throughout the motion arc.
Collapse
Affiliation(s)
- Takafumi Hiranaka
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan.
| | - Masamune Kamachi
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan
| | - Takuma Hayashi
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan
| | - Ryoma Inoue
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan
| | - Sota Ogino
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan
| | - Motoki Koide
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan
| | - Takaaki Fujishiro
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan
| | - Koji Okamoto
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- cho, Takatsuki, Osaka, 569-1192, Japan
| |
Collapse
|
3
|
Hiranaka T, Fukai Y, Tanaka S, Okajima T, Kanno T, Koide M, Fujishiro T, Okamoto K. Pre-milling technique improves the accuracy of posterior femoral condyle cut and reduces the tibial recut in Oxford unicompartmental knee arthroplasty. Arch Orthop Trauma Surg 2024; 144:2761-2766. [PMID: 38693288 DOI: 10.1007/s00402-024-05333-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 04/14/2024] [Indexed: 05/03/2024]
Abstract
BACKGROUND Recuts are sometimes needed in UKA because of inadequate posterior tibial cut thickness. We investigated the efficacy of a pre-milling technique (the first milling is done prior to the posterior condylar cut) in Oxford unicompartmental knee arthroplasty to enhance bone cut thickness and to minimize tibial recuts. PATIENTS AND METHODS Between January 2021 and January 2023, a posterior condyle cut was made before milling in 213 knees in 152 patients (conventional group), while the pre-milling technique was used in 198 knees in 140 patients (pre-milling group). The thickness of the posterior condyle and the rate of tibial recuts were compared between the groups. RESULTS The bone cut thickness was thinner in the conventional group than in the pre-milling group in small-size (4.7 mm ± 0.6 mm and 5.0 mm ± 0.6 mm, P = 0.0001) and in medium-size (5.1 mm ± 0.5 mm and 5.4 mm ± 0.5 mm, 0.0001) femoral components, whereas there was no difference in large-size femoral components. However, the thickness was still less than the component thickness (5.17 mm for small, 5.57 mm for medium and 6.17 mm for large) in both groups. Tibial recuts were more prevalent in the conventional group than in the pre-milling group (14 knees, 7%, 3 knees 2%, P = 0.002). CONCLUSIONS The pre-milling technique was found to increase the bone cut thickness in small and medium femoral components, reducing the need for tibial recuts. Further research is warranted to optimize the pre-milling technique and to investigate its long-term impact on patient outcomes.
Collapse
Affiliation(s)
- Takafumi Hiranaka
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan.
| | - Yasuhiro Fukai
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan
| | - Sho Tanaka
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan
| | - Takahiro Okajima
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan
| | - Tatsuhiko Kanno
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan
| | - Motoki Koide
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan
| | - Takaaki Fujishiro
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan
| | - Koji Okamoto
- Department of Orthopaedic Surgery and Joint Surgery Centre, Takatsuki General Hospital, 1-3-13, Kosobe- Cho, Takatsuki City, Osaka, 561-1115, Japan
| |
Collapse
|
4
|
Shih HT, Chen KH, Lee CH, Tu KC, Wang SP. Factors predicting lower limb alignment after Oxford medial unicompartmental knee arthroplasty. Sci Rep 2024; 14:5597. [PMID: 38454143 PMCID: PMC10920632 DOI: 10.1038/s41598-024-56285-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 03/05/2024] [Indexed: 03/09/2024] Open
Abstract
This study aimed to identify the factors affecting hip-knee-ankle (HKA) angle following Oxford medial unicompartmental knee arthroplasty (MUKA). A retrospective analysis of 200 patients who underwent Oxford MUKA from June 2018 to October 2020 was conducted. Univariate and multivariate analyses were performed to investigate the impact of surgical and radiographic characteristics on the postoperative HKA angle. The mean HKA angle was 9.5 ± 4.3° before surgery and 3.6 ± 3.7° after surgery (p < 0.001). The postoperative HKA angle significantly correlated with the preoperative HKA angle, bearing size, tibial component alignment angle, and BMI (r = 0.71, p < 0.001; r = - 0.24, p = 0.001; r = 0.21, p = 0.004; r = - 0.18, p = 0.011). Multiple linear regression analysis revealed that the preoperative HKA angle (β = 0.68, p < 0.001), bearing size (β = - 0.31, p < 0.001), tibial component alignment angle (β = 0.14, p = 0.003), and BMI (β = - 0.09, p = 0.047) significantly affected the postoperative HKA angle. In conclusion, larger preoperative varus deformity, smaller bearing size, greater varus alignment of the tibial component, and lower BMI lead to greater postoperative varus alignment of the lower limb in Oxford MUKA. With this concept, surgeons can more accurately predict postoperative lower limb alignment and avoid malalignment in Oxford MUKA.
Collapse
Affiliation(s)
- Han-Ting Shih
- Department of Orthopaedics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung, 40705, Taiwan
| | - Kun-Hui Chen
- Department of Orthopaedics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung, 40705, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
- Department of Computer Science and Information Engineering, Providence University, Taichung, Taiwan
| | - Cheng-Hung Lee
- Department of Orthopaedics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung, 40705, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
- Department of Food Science and Technology, HungKuang University, Taichung, Taiwan
| | - Kao-Chang Tu
- Department of Orthopaedics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung, 40705, Taiwan
| | - Shun-Ping Wang
- Department of Orthopaedics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung, 40705, Taiwan.
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan.
| |
Collapse
|
5
|
Radiographic comparison of mobile-bearing partial knee single-peg versus twin-peg design. J Arthroplasty 2015; 30:475-8. [PMID: 25453627 DOI: 10.1016/j.arth.2014.10.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/23/2014] [Accepted: 10/10/2014] [Indexed: 02/01/2023] Open
Abstract
The femoral component and proprietary instrumentation of a mobile-bearing unicompartmental knee arthroplasty (UKA) was redesigned with an additional peg for enhanced fixation, 15° of extra femoral surface for contact in deep flexion, more rounded profile, better fit into the milled surface, and redesigned intramedullary based instrumentation. To assess the benefit of these changes, we compared postoperative radiographs of 219 single-peg and 186 twin-peg UKAs done in 2008-2011. All surviving knees demonstrated satisfactory position and alignment with no radiolucencies observed. Radiographic analysis showed improved and consistent component positioning with the twin-peg design implanted with updated instrumentation compared with the single-peg. The radiographic benefits of improved implant positioning using the twin-peg component and updated instrumentation are clear and carry tremendous potential. More robust follow-up is imperative.
Collapse
|