Introduction: 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.
Materials and 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.
Conclusion: TT proximalization osteotomy provides satisfactory results in improving a lack of flexion and pain in patella baja post-TKR.
Keywords: Knee stiffness; TKA; Tibial tuberosity osteotomy.