title: Proximalize osteotomy of tibial tuberosity (POTT) as a treatment for stiffness secondary to patella baja in total knee arthroplasty (TKA).
abstract: BACKGROUND
  Stiffness after a total knee arthroplasty (TKA) is one of the most common post-operative complications. The purpose of this study is the evaluation of the effectiveness of TT proximalization osteotomy of improving a lack of flexion and secondary pain in patella baja (infera) post-TKA.
  
  
  METHODS
  Between April 2007 and July 2012, TT proximalization osteotomy was performed on 21 patients. The average preoperative flexion was 70° (in a range of 60-80). Clinical pre- and post-operative evaluations were performed with Knee Society Score, Western Ontario and McMaster Universities Arthritis Index scales and a satisfaction survey. Modified Blackburn-Peel index and Portner angle were used to evaluate patellar height.
  
  
  RESULTS
  After an average follow-up of 35 months (range 18-48), an average flexion of 100° (range 90-100) and an overall satisfaction were obtained. Clinical scores improved significantly. The Blackburn-Peel index and Portner angle improved significantly from 0.3 (range 0.1-0.5) to 0.4 (0.3-0.5) and from 9 (3-15) to 12 (9-18), respectively. Three patients showed no signs of osteotomy consolidation. However, this was not linked to a lack of extension or an increase in local pain.
  
  
  CONCLUSIONS
  TT proximalization osteotomy provides satisfactory results in improving a lack of flexion and pain in patella baja post-TKR.
authors: Resident Trauma and Orthopaedic Surgery Department, Hospital Clínic Barcelona, Villarroel 170, Barcelona, Spain. vives1@clinic.ub.es.
authors: M A
authors: MA
authors: Vives-Barquiel
authors: IDIBAPS, Roselló 149, Barcelona, Spain.
authors: A
authors: A
authors: Torrents
authors: Knee Unit, Hospital Clínic Barcelona, Villarroel 170, Barcelona, Spain.
authors: L
authors: L
authors: Lozano
authors: Knee Unit, Hospital Clínic Barcelona, Villarroel 170, Barcelona, Spain.
authors: J C
authors: JC
authors: Martínez-Pastor
authors: Knee Unit, Hospital Clínic Barcelona, Villarroel 170, Barcelona, Spain.
authors: F
authors: F
authors: Maculé
authors: Resident Trauma and Orthopaedic Surgery Department, Hospital Clínic Barcelona, Villarroel 170, Barcelona, Spain.
authors: J M
authors: JM
authors: Segur
authors: Knee Unit, Hospital Clínic Barcelona, Villarroel 170, Barcelona, Spain.
authors: D
authors: D
authors: Popescu
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010027:Osteotomy / Q000379:methods*; D010329:Patella / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D016059:Range of Motion, Articular; D012086:Reoperation; D013977:Tibia / Q000601:surgery*
keywords: Knee stiffness; TKA; Tibial tuberosity osteotomy