Single-Stage TKA Achieves 75% Full Alignment in Extra-Articular Deformities: Study Finds
A recent study reveals that performing single-stage total knee arthroplasty (TKA) provides a highly effective and safe solution for extra-articular varus deformities, attaining full alignment correction in 75% of patients.
The findings were published in the International Journal of Medicine and Public Health in September 2025.
Addressing the global burden of knee osteoarthritis (OA) and the technical complexities of managing extra-articular deformities (EAD), Sateesh Chandra P of the Osmania Medical College and Hospital noticed the existing clinical data gap regarding functional outcomes in these difficult cases. This research aims to assess the efficacy of employing intra-articular corrections within a single-stage total knee replacement (TKR) to resolve these structural femoral or tibial misalignments.
The prospective study involved 20 patients (aged 50–70) presenting with coronal varus deformities under 20 degrees in the femur and 30 degrees in the tibia, while excluding those with neurovascular deficits or inflammatory diseases like rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Surgical management featured single-stage arthroplasty with soft tissue release and intra-articular bone resections. Clinical progress was objectively monitored using the Knee Society Score (KSS) and Hungerford score across a structured follow-up schedule of 6, 12, and 18 months.
Key Clinical Findings of Study:
- Superior Alignment Correction: The surgical approach successfully achieved full coronal alignment correction in 75% of participants, while the remaining 25% reached partial correction.
- Enhanced Functional Outcomes: Clinical evaluations demonstrated a significant boost in the mean KSS, which rose from a preoperative 50.21 to 86.01 postoperatively, representing a mean functional improvement of 35.80 points.
- Improved Joint Vitality: Overall joint health saw substantial gains as the mean Hungerford score increased from 49.98 to 83.98 at the final follow-up, reflecting a highly significant mean difference of 34.00 points.
- Restored Clinical Mobility: Patients experienced a marked expansion in their mean range of motion (ROM), which increased from 67.93 degrees to 91.63 degrees, indicating a significant postoperative mobility gain of 23.70 degrees.
- Favorable Safety Profile: The single-stage procedure was validated as a secure intervention, with the study reporting zero postoperative complications or adverse effects among all participants.
The results suggest that single-stage TKA is a safe and effective strategy for correcting extra-articular varus deformities, achieving full alignment in 75% of cases with no reported complications. This surgical approach significantly enhances functional health, evidenced by mean KSS increasing from 50.21 to 86.01 and Hungerford scores rising from 49.98 to 83.98.
Single-stage TKA utilizing intra-articular corrections serves as a safe and effective clinical strategy for managing complex extra-articular varus deformities, significantly improving functional outcomes and patient quality of life while offering a streamlined alternative to higher-risk multi-stage procedures
While the findings are encouraging, the study's broader applicability is constrained by a modest sample size of 20 patients at a single institution and an 18-month follow-up period that may not fully reflect long-term durability or delayed complications
Reference
Sateesh Chandra P, Sreekanth Reddy B, Thulasiram K. AN OBSERVATIONAL STUDY OF FUNCTIONAL OUTCOME OF EXTRA-ARTICULAR DEFORMITIES CORRECTED WITH INTRA-ARTICULAR CORRECTIONS IN PRIMARY TOTAL KNEE REPLACEMENT. International Journal of Medicine and Public Health 2025; 15(3): 1-6.
