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Blackwood NO, Blitz JA, Vopat B, Ierulli VK, Mulcahey MK. Medial Collateral Ligament Reconstruction With Autograft Versus Allograft: A Systematic Review. Am J Sports Med 2024:3635465231225982. [PMID: 38476106 DOI: 10.1177/03635465231225982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
BACKGROUND Medial collateral ligament (MCL) reconstruction (MCLR) is performed after failed nonoperative treatment or high-grade MCL injury with associated valgus instability. PURPOSE To evaluate clinical outcomes after MCLR with autograft versus allograft. STUDY DESIGN Systematic review, Level of evidence, 4. METHODS A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The authors conducted a search of the PubMed, CINAHL, EMBASE, and Cochrane databases to identify studies comparing outcomes of MCLR with autograft versus allograft. Studies were included if they evaluated clinical outcomes after MCLR using autograft and/or allograft. Any study that included concomitant knee ligament injury other than the anterior cruciate ligament injury was excluded. A quality assessment was performed using the modified Coleman Methodology Score. RESULTS The initial search identified 746 studies, 17 of which met the inclusion criteria and were included in this review. The studies included 307 patients: 151 (49.2%) patients received autografts, and 156 (50.8%) received allografts. The most used autograft was the semitendinosus tendon (136 grafts; 90.1% of specified allografts), and the only allograft used was the Achilles tendon (110 grafts; 100% of specified autografts). The mean follow-up of the studies was 25.6 months. Postoperative pain (Lysholm scores) ranged from 82.9 to 94.8 in patients receiving autografts and 87.5 to 93 in patients receiving allografts. Postoperative range of motion was full in 8 of 15 (53.3%) patients receiving autografts compared with 82 of 93 (88.2%) patients receiving allografts. Five of the 151 (3.3%) patients who had MCLR with autografts had complications such as infection, instability, and prominent screws. Two of the 156 (1.3%) MCLRs with allografts developed complications of prominent screws and nonhealing incisions. CONCLUSION MCLR with either autografts or allografts leads to improved patient-reported, radiographic, and clinical outcomes. Patient-reported postoperative pain was similar in patients receiving either graft type. Other outcomes were difficult to compare between graft types because of nonstandardized reporting and a lack of pre- and postoperative measurements. Therefore, there is no evidence of significantly improved outcomes in the use of either autograft or allograft with MCLR.
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Affiliation(s)
| | - Jack A Blitz
- Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Bryan Vopat
- Department of Orthopedic Surgery and Sports Medicine, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Victoria K Ierulli
- Department of Orthopaedic Surgery, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Mary K Mulcahey
- Department of Orthopaedic Surgery and Rehabilitation, Loyola University Medical Center, Maywood, Illinois, USA
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Sun C, Rong W, Du R, Wu S, Liu P, Zhang W, Cai X. Meniscus Graft Augmentation for a Midsubstance Tear of the Medial Collateral Ligament during Total Knee Arthroplasty. J Knee Surg 2022; 35:449-455. [PMID: 32838462 DOI: 10.1055/s-0040-1715115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Multiple surgical techniques exist to repair iatrogenic medial collateral ligament (MCL) injury during total knee arthroplasty (TKA). The objective of the study is to confirm the clinical effectiveness of meniscus transfer for treatment of iatrogenic MCL midsubstance transection in which remaining MCL is of poor quality, and there is a persistent gap between both ligament ends during TKA. From January 2015 to November 2019, we treated 11 patients with MCL injuries of 882 primary TKAs by meniscus transfer. Another 24 primary TKAs were recruited as a control group. The two groups of patients were comparable for age, gender, body mass index (BMI), Knee Society scoring (KSS), knee function score (KFS), and type of prosthesis comparison without significant difference (p > 0.05). We reviewed the patient's stability, as well as objective measures such as KSS and KFS scores, physical examinations, and radiographs. No patient of either group reported impaired wound healing, joint instability on physical examination, pain, radiographic changes, signs of loosening, and other complications. At the final follow-up, there was no significant difference in terms of KSS (p = 0.780) and KFS (p = 0.612) between the injury group and control group at last follow-up. X-ray image review showed no prosthesis loosening or subsidence for both groups. Based on these results, we are cautiously optimistic that midsubstance transections in which the quality of remaining tendon is weak, there is suspicion of stretching, or there is a persistent gap between both ligament ends that can be reconstructed with meniscus autograft transfer augmentation and an unconstrained implant.
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Affiliation(s)
- Changjiao Sun
- Department of Orthopedic, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Dongxiaokou Town, Changping District, Beijing, People's Republic of China
| | - Wei Rong
- Department of Orthopedic, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Dongxiaokou Town, Changping District, Beijing, People's Republic of China
| | - Ruiyong Du
- Department of Orthopedic, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Dongxiaokou Town, Changping District, Beijing, People's Republic of China
| | - Sha Wu
- Department of Orthopedic, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Dongxiaokou Town, Changping District, Beijing, People's Republic of China
| | - Pu Liu
- Department of Orthopedic, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Dongxiaokou Town, Changping District, Beijing, People's Republic of China
| | - Wei Zhang
- Department of Orthopedic, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Dongxiaokou Town, Changping District, Beijing, People's Republic of China
| | - Xu Cai
- Department of Orthopedic, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Dongxiaokou Town, Changping District, Beijing, People's Republic of China
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Mou P, Zeng Y, Pei F, Zhou Z, Shen B, Kang P, Yang J. Medial femoral epicondyle upsliding osteotomy with posterior stabilized arthroplasty provided good clinical outcomes such as constrained arthroplasty in primary total knee arthroplasty with severe valgus deformity. Knee Surg Sports Traumatol Arthrosc 2019; 27:2266-2275. [PMID: 30430221 DOI: 10.1007/s00167-018-5292-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 11/09/2018] [Indexed: 02/05/2023]
Abstract
PURPOSE A modified technique referred to as a medial femoral epicondyle upsliding osteotomy was proposed to address severe valgus deformity with unconstrained posterior stabilized (PS) arthroplasty. The study compared the effectiveness of the technique and PS arthroplasty with constrained arthroplasty during primary total knee arthroplasty (TKA). METHODS Fifty-three patients presenting with valgus knees with a mean valgus angle (VA) greater than 30° were prospectively randomized and divided into two groups, and both groups received primary TKA. Upsliding osteotomy with PS arthroplasty was performed on the knees of 27 patients (group A), while the remaining 26 patients (group B) received a constrained arthroplasty. The Knee Society function score (KSF), Hospital for Special Surgery knee score (HSS), range of motion (ROM), mediolateral stability and hospitalization expenses were recorded. The hip-knee-ankle angle (HKA), femorotibial angle (FTA) and VA were analysed. Complications were also recorded. RESULTS The patients received follow-up care for more than 50 months. The postoperative KSF, HSS and ROM showed marked improvement in both groups (p < 0.05). Radiological assessments showed that HKA, FTA and VA for group A were restored to (179.9 ± 3.0)°, (173.0 ± 2.4)° and (7.0 ± 2.4)°, respectively. For group B, the HKA, FTA and VA were restored to (181.5 ± 2.3)°, (172.5 ± 2.3)° and (7.5 ± 2.3)°, respectively. Only two patients from group A demonstrated mild medial laxity in their knees, and the remaining patients from both groups were stable medially and laterally. However, the total hospitalization expenses and material expenses of group A were less than those of group B because of the more expensive constrained prosthesis and stems. No late-onset loosening or recurrent valgus deformity was displayed. CONCLUSIONS Both medial femoral epicondyle upsliding osteotomy with PS arthroplasty and constrained arthroplasty showed good outcomes for the restoration of neutral limb alignment and soft tissue balance, which are demonstrated to be safe and effective techniques for correcting severely valgus knees. Therefore, the clinically important finding of this study is that medial femoral epicondyle upsliding osteotomy with PS arthroplasty can be an alternative method for correcting severe valgus knees. LEVEL OF EVIDENCE II.
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Affiliation(s)
- Ping Mou
- Department of Orthopedic Surgery, West China Hospital, West China Medical School, Sichuan University, #37 Guoxue Road, Chengdu, 610041, Sichuan, People's Republic of China
| | - Yi Zeng
- Department of Orthopedic Surgery, West China Hospital, West China Medical School, Sichuan University, #37 Guoxue Road, Chengdu, 610041, Sichuan, People's Republic of China
| | - Fuxing Pei
- Department of Orthopedic Surgery, West China Hospital, West China Medical School, Sichuan University, #37 Guoxue Road, Chengdu, 610041, Sichuan, People's Republic of China
| | - Zongke Zhou
- Department of Orthopedic Surgery, West China Hospital, West China Medical School, Sichuan University, #37 Guoxue Road, Chengdu, 610041, Sichuan, People's Republic of China
| | - Bin Shen
- Department of Orthopedic Surgery, West China Hospital, West China Medical School, Sichuan University, #37 Guoxue Road, Chengdu, 610041, Sichuan, People's Republic of China
| | - Pengde Kang
- Department of Orthopedic Surgery, West China Hospital, West China Medical School, Sichuan University, #37 Guoxue Road, Chengdu, 610041, Sichuan, People's Republic of China
| | - Jing Yang
- Department of Orthopedic Surgery, West China Hospital, West China Medical School, Sichuan University, #37 Guoxue Road, Chengdu, 610041, Sichuan, People's Republic of China.
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An in vitro analysis of medial structures and a medial soft tissue reconstruction in a constrained condylar total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2017; 25:2646-2655. [PMID: 27026029 PMCID: PMC5522503 DOI: 10.1007/s00167-016-4087-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 03/14/2016] [Indexed: 02/02/2023]
Abstract
PURPOSE The aim of this study was to quantify the medial soft tissue contributions to stability following constrained condylar (CC) total knee arthroplasty (TKA) and determine whether a medial reconstruction could restore stability to a soft tissue-deficient, CC-TKA knee. METHODS Eight cadaveric knees were mounted in a robotic system and tested at 0°, 30°, 60°, and 90° of flexion with ±50 N anterior-posterior force, ±8 Nm varus-valgus, and ±5 Nm internal-external torque. The deep and superficial medial collateral ligaments (dMCL, sMCL) and posteromedial capsule (PMC) were transected and their relative contributions to stabilising the applied loads were quantified. After complete medial soft tissue transection, a reconstruction using a semitendinosus tendon graft was performed, and the effect on kinematic behaviour under equivocal conditions was measured. RESULTS In the CC-TKA knee, the sMCL was the major medial restraint in anterior drawer, internal-external, and valgus rotation. No significant differences were found between the rotational laxities of the reconstructed knee to the pre-deficient state for the arc of motion examined. The relative contribution of the reconstruction was higher in valgus rotation at 60° than the sMCL; otherwise, the contribution of the reconstruction was similar to that of the sMCL. CONCLUSION There is contention whether a CC-TKA can function with medial deficiency or more constraint is required. This work has shown that a CC-TKA may not provide enough stability with an absent sMCL. However, in such cases, combining the CC-TKA with a medial soft tissue reconstruction may be considered as an alternative to a hinged implant.
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Ligament reconstruction/advancement for management of instability due to ligament insufficiency during total knee arthroplasty: a viable alternative to constrained implant. J Orthop Sci 2014; 19:564-70. [PMID: 24771137 DOI: 10.1007/s00776-014-0564-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 03/26/2014] [Indexed: 02/09/2023]
Abstract
BACKGROUND We aimed to assess the results of ligament reconstruction/advancement for the management of ligament insufficiency during total knee arthroplasty. METHOD We retrospectively reviewed the results of ligament reconstruction/advancement for management of instability due to ligament insufficiency during total knee arthroplasty (TKA). Between January 2001 and January 2008 collateral ligament reconstruction/advancement was done in 15 patients. Wherever ligament advancement was not possible (mid-substance tear) ligament reconstruction was done using the hamstring tendon. Knee society scores were calculated and Kaplan-Meier survival analysis was done. RESULTS Average follow-up was 6.2 years. No patient developed instability until the last follow-up, except one patient who required revision due to instability at six years after primary surgery. CONCLUSION We concluded from this study that ligament reconstruction/advancement during TKA is a viable option to address instability due to ligament insufficiency.
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Tigani D, Dallari D, Coppola C, Ben Ayad R, Sabbioni G, Fosco M. Total knee arthroplasty for post-traumatic proximal tibial bone defect: three cases report. Open Orthop J 2011; 5:143-50. [PMID: 21584202 PMCID: PMC3093746 DOI: 10.2174/1874325001105010143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 11/29/2010] [Accepted: 12/12/2010] [Indexed: 11/22/2022] Open
Abstract
Bone stock deficiency in primary as well as in revision total knee arthroplasty (TKA) represents a difficult problem to surgeon with regard to maintaining proper alignment of the implant components and in establishing a stable bone-implant interface. Different surgical procedures are available in these situations, for instances the use of bone cement, prosthetic augments, custom implant, and wire mesh with morsellized bone grafting and structural bone allograft. Structural allograft offers a numerous advantages as easy remodeling and felling cavitary or segmental defects, excellent biocompatibility, bone stock restoration and potential for ligamentous reattachment. In this article we report a short term result of three cases affected by severe segmental medial post/traumatic tibial plateau defect in arthritic knee, for which massive structural allograft reconstruction and primary total knee replacement were carried. The heights of the bone defect were between 27-33 mm and with moderate medio-lateral knee instability. Pre-operative AKS score in three cases was 30, 34 and 51 points consecutively and improved at the last follow-up to 83, 78 and 85 consecutively. No acute or chronic complication was observed. Last radiological exam referred no signs of prosthetic loosening, no secondary resorption of bone graft and well integrated graft to host bone. These results achieved in our similar three cases have confirmed that the structural bone allograft is a successful biological material to restore hemi-condylar segmental tibial bone defect when total knee replacement is indicated.
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Affiliation(s)
- D Tigani
- 7 Division Orthopaedic & Traumathology Department, Rizzoli Orthopaedic Institute, bologna, Italy
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Ohnsorge JAK, Wickiewicz TL, Davis J, Laskin RS. Revision knee arthroplasty including reconstruction of the lateral collateral ligament by allograft: a case report. HSS J 2010; 6:219-22. [PMID: 21886539 PMCID: PMC2926367 DOI: 10.1007/s11420-009-9139-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Accepted: 10/08/2009] [Indexed: 02/07/2023]
Abstract
A 53-year-old woman presented with an unstable and painful total knee arthroplasty 6 months after the index procedure. Disruption of both collateral ligaments as a young adult and the subsequent development of traumatic arthritis required repeated surgical and extensive conservative treatment before a prosthesis was implanted. Examination disclosed marked instability of the lateral collateral ligament (LCL) and loosening of the tibial and the femoral components. Review of the MRI obtained prior to the total knee replacement revealed discontinuity of the LCL with intense scarring of the posterolateral ligament complex. Definitive management of this twofold problem was not helped by literature review, which failed to reveal a gold standard or a broad consensus as a rationale for treatment. Consequently, an individual approach to the problem was defined: A one-stage revision arthroplasty was performed using a modular non-articulated constrained prosthesis and a bone-tendon-bone allograft to reconstruct the LCL in a one-stage operation. Postoperative rehabilitation included continuous passive motion, which was begun immediately after surgery and was gradually increased to 90° of flexion. The LCL reconstruction was initially protected in a hinged knee brace and weight-bearing was initially limited to toe-touch and gradually increased over 6 weeks. Pain-free motion to 0-115° flexion was achieved at 3 months after surgery and the patient had returned to her normal activities. The 4-year-follow-up displayed a stable and functional knee with no evidence of loosening or wear.
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Affiliation(s)
- Jörg A. K. Ohnsorge
- Department of Orthopaedic Surgery, Klinik für Orthopädie und Unfallchirurgie, Universitätsklinikum Aachen, RWTH, University of Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany
| | | | - Jack Davis
- Hospital for Special Surgery, 535 East 70th Street, New York, NY USA
| | - Richard S. Laskin
- Hospital for Special Surgery, 535 East 70th Street, New York, NY USA
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Microvascular flaps and collateral ligament reconstructions for soft tissue sarcomas at the knee joint. Ann Plast Surg 2010; 64:24-7. [PMID: 20023452 DOI: 10.1097/sap.0b013e3181a20adf] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We report the suitability of free flap reconstruction in defects around the knee joint caused by soft tissue sarcoma (STS) excisions. The importance of collateral ligament reconstruction is also evaluated.Between years 1993 and 2005, 15 STS patients having a STS at the knee area with the need for free flap were treated in Helsinki University Hospital. Eleven musculocutaneous latissimus dorsi, 3 fasciocutaneous anterolateral thigh flaps, and 1 osteomusculocutaneous latissimus dorsi were used. The reconstruction of collateral ligaments was performed for 7 patients, 4 medial and 3 lateral; 6 with bone-tendon-bone grafts from patellar tendon and 1 with pes anserinus tendon transposition.There was no postoperative mortality. One flap was lost. Five patients needed debridement for minor wound complications. The mean follow-up time was 64 months. There were no local recurrences. Distant metastasis developed after the operation in 5 patients. Of these, 2 patients with solitary soft tissue metastasis were operated, and they are disease free. At 5 years 79% were disease-free. One patient with medial collateral reconstruction had recurrent patellar displacement and needed further operations; another with lateral collateral ligament and posterior capsular excision, that was not reconstructed, had lateral instability of the knee and needed orthosis.Free flap for STS of the knee is a reliable method. Patients can be operated with wider marginals and prognosis is good. Ligament reconstruction can be performed simultaneously, if collateral ligaments are excised.
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Toms AD, Mandalia V, Haigh R, Hopwood B. The management of patients with painful total knee replacement. ACTA ACUST UNITED AC 2009; 91:143-50. [PMID: 19190044 DOI: 10.1302/0301-620x.91b2.20995] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The management of patients with a painful total knee replacement requires careful assessment and a stepwise approach in order to diagnose the underlying pathology accurately. The management should include a multidisciplinary approach to the patient's pain as well as addressing the underlying aetiology. Pain should be treated with appropriate analgesia, according to the analgesic ladder of the World Health Organisation. Special measures should be taken to identify and to treat any neuropathic pain. There are a number of intrinsic and extrinsic causes of a painful knee replacement which should be identified and treated early. Patients with unexplained pain and without any recognised pathology should be treated conservatively since they may improve over a period of time and rarely do so after a revision operation.
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Affiliation(s)
- A D Toms
- Exeter Knee Reconstruction Unit, Royal Devon & Exeter Hospital, Barrack Road, Exeter EX2 5DW, UK.
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Pietsch M, Hofmann S. Von der tibiofemoralen Instabilität zur Luxation in der Knieendoprothetik. DER ORTHOPADE 2007; 36:917-22, 924-7. [PMID: 17876569 DOI: 10.1007/s00132-007-1142-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Tibiofemoral instability is increasingly recognized as a mode of failure in total knee arthroplasty (TKA). Severe instability may lead to dislocation. Wrong surgical technique and wrong choice of constraint of the prostheses are the main causes for instability. Malalignment, malrotation and intraoperatively uncorrected instability especially in flexion may lead to an unstable total knee arthroplasty. Cruciate-retaining designs and mobile platforms can be considered only in the presence of well-balanced ligaments. Cruciate-substituting designs give more stability and many people find them more forgiving. However, correction of varus-valgus instability and severe flexion laxity cannot be provided. Varus-valgus contrained designs cannot compensate for the absence of medial and lateral collateral ligaments. Such cases are most reliably treated with a linked implant (rotating hinge). The exact analysis of the cause of an unstable or dislocated total knee arthroplasty represents the most essential basis of a successful treatment. Exchange of the prostheses represents the most successful procedure. Correction of implantation failures should be performed. A more constrained design should be used if insufficient ligaments are found. Post-traumatic instability or dislocation represents an exception.
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Affiliation(s)
- M Pietsch
- Abteilung für Orthopädie und orthopädische Chirurgie, Allgemeines und orthopädisches LKH Stolzalpe, Stolzalpe, Osterreich.
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Vince KG, Abdeen A, Sugimori T. The unstable total knee arthroplasty: causes and cures. J Arthroplasty 2006; 21:44-9. [PMID: 16781428 DOI: 10.1016/j.arth.2006.02.101] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Accepted: 02/13/2006] [Indexed: 02/01/2023] Open
Abstract
Surgery for the unstable total knee arthroplasty requires a deep understanding of the causes and a plan that specifically addresses them. Isolated ligament reconstructions and polyethylene insert exchanges generally do not work. Patients may experience "buckling" from pain, flexion contracture, recurvatum, or patellar problems. True mechanical instability may result from loosening, bone loss, prosthetic breakage, component size or position, fracture, wear, or collateral ligament failure. Only the last one typically requires a constrained implant. The possible modes (directions) of instability are the following: varus-valgus, recurvatum, flexion, and global. Revision surgery must eliminate deforming forces, most frequently frontal plane alignment. Prosthetic implants, no matter how well engineered, are not a substitute for diagnosis and surgical technique.
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Affiliation(s)
- Kelly G Vince
- Department of Orthopaedic Surgery, Keck School of Medicine of the University of Southern California, Health Consultation Center II, Los Angeles, California 90033, USA
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