Total knee arthroplasty in patients with substantial deformities using primary knee components
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Although advocated for severe varus and valgus deformities, constrained implant designs are associated with a number of disadvantages in total knee arthroplasty (TKA). Combining a minimally invasive surgical approach with an interchangeable posterior stabilized (PS) implant design may allow adequate soft tissue balancing with a minimal amount of constraint and without residual instability.
Retrospectively 51 patients operated with the minimally invasive far medial subvastus approach for severe varus or valgus deformity, who underwent primary TKA with a fully interchangeable PS implant (Vanguard, Biomet Inc., Warsaw IN, USA) between 2009 and 2013 were examined. Soft tissue releases was performed using a piecrust needling technique. Preoperative alignment and surgical parameters were collected for all patients. All patients underwent preoperative and follow-up radiographic assessment and completed a battery of clinical assessments.
All procedures were performed successfully, with alignment improving from a preoperative mean (SD) varus deformity of 165° (3°) and a mean (SD) valgus deformity of 196° (4.5°) to an overall mean (SD) postoperative mechanical alignment of 179.5° (3.0°). Nine patients had postoperative varus, while three patients had a postoperative valgus deviation from neutral alignment >3°. The mean change in joint line position in extension was −0.0 ± 0.6 mm. Clinical scores at final follow-up were excellent for both groups.
Good TKA outcomes can be achieved in patients with substantial varus or valgus deformities using a combination of a minimally invasive far medial subvastus approach, interchangeable PS implants and soft tissue releases with a piecrust needling technique.
Level of evidence
KeywordsTotal knee arthroplasty Minimally invasive surgery Posterior stabilized Prosthesis design Joint deformity
- 4.Behrend H, Giesinger K, Giesinger JM, Kuster MS (2012) The “forgotten joint” as the ultimate goal in joint arthroplasty: validation of a new patient-reported outcome measure. J Arthroplasty 27:430–436Google Scholar
- 14.Elkus M, Ranawat CS, Rasquinha VJ, Babhulkar S, Rossi R, Ranawat AS (2004) Total knee arthroplasty for severe valgus deformity. Five to fourteen-year follow-up. J Bone Joint Surg Am 86-A(12):2671–2676Google Scholar
- 27.Lombardi AV, Jr., Dodds KL, Berend KR, Mallory TH, Adams JB (2004) An algorithmic approach to total knee arthroplasty in the valgus knee. J Bone Joint Surg Am 86-A Suppl 2:62–71Google Scholar
- 33.Mihalko WM, Miller C, Krackow KA (2000) Total knee arthroplasty ligament balancing and gap kinematics with posterior cruciate ligament retention and sacrifice. Am J Orthop (Belle Mead NJ) 29(8):610–616Google Scholar
- 36.Morgan H, Battista V, Leopold S (2005) Constraint in primary total knee arthroplasty. J Am Acad Orthop Surg 18(8):515–524Google Scholar
- 43.Rajgopal A, Dahiya V, Vasdev A, Kochhar H, Tyagi V (2011) Long-term results of total knee arthroplasty for valgus knees: soft-tissue release technique and implant selection. J Orthop Surg (Hong Kong) 19(1):60–63Google Scholar
- 44.Ranawat AS, Ranawat CS, Elkus M, Rasquinha VJ, Rossi R, Babhulkar S (2005) Total knee arthroplasty for severe valgus deformity. J Bone Joint Surg Am 87(Suppl 1):271–284Google Scholar
- 45.Ritter M, Davis K, Meding J, Pierson J, Berend M, Malinzak R (2011) The effect of alignment and BMI on failure of total knee replacement. J Bone Joint Surg [Am] 93A(17):1588–1596Google Scholar
- 51.Thienpont E (2012) Prosthesis selection: choosing the right type of constraint. In: Parvizi J (ed) Principles and techniques in revision total knee arthroplasty. American Academy of Orthopaedic Surgeons, Rosemount, pp 29–39Google Scholar