Comparison of Restricted Versus Unrestricted Kinematic Alignment in 1ry TKA

Not Applicable

Not yet recruiting

• Conditions: Osteoarthritis (OA) of the Knee; Total Knee Anthroplasty

• Registration Number: NCT06726993
• Lead Sponsor: Assiut University

Brief Summary

Knee osteoarthritis is a growing socioeconomic burden because of the ageing and obesity. By 2030, the majority of individuals undergoing knee arthroplasty in USA will be those younger than 65 years, with up to 1 million achieved annually.

The definitive treatment for knee joint degeneration is total knee arthroplasty.

Detailed Description

Furthermore, the commonest technique is neutral mechanical alignment total knee arthroplasty. Latest studies have revealed that the mechanical alignment technique repeatedly causing substantial anatomical alterations with a widespread of complex collateral ligament imbalances, which are not repairable by collateral ligament release. Consequently, the total knee arthroplasty individuals walk with an abnormal gait, and they do not experience a normal knee joint. This may be one of the causes that up to 20% of total knee arthroplasty individuals are disappointed, and over 50% may have remaining symptoms.

Consequently, the conventional mechanical alignment technique has been recently challenged by a new alternative technique, namely unrestricted kinematic alignment proposed by Howell, as a possible solution to the high dissatisfaction following total knee arthroplasty, aiming at reproducing the constitutional tibiofemoral tridimensional alignment and knee laxity. It is almost a pure bone procedure with only exceptional collateral ligament release, which has been shown to reliably position knee components.

The restricted kinematic alignment protocol suggested by Vendittoli has been developed as an alternative to the unrestricted kinematic alignment for patients with an outlier or atypical knee anatomy. The restricted kinematic alignment is founded on five principles: hip-knee-ankle angle should be maintained within ± 3° postoperatively; a limitation to a maximum of 5° for lateral distal femoral angle and medial proximal tibial angle may be considered; restoration of collateral ligament balance should be achieved without the gap balancing technique; native femoral anatomy preservation is suggested over tibial one to maintain knee biomechanics; resurface resection must be accomplished on the unworn side with a thickness equivalent to the width of the implant;cut fine-tuning may be sought at the worn side.

Study Timeline

• Status Verified: 2024-12
• Study First Submitted: 2024-12-05
• Study First Submitted QC: 2024-12-05
• Study First Posted: 2024-12-10
• Last Update Submitted: 2024-12-16
• Last Update Posted: 2024-12-19
• Study Start: 2025-02-01
• Primary Completion: 2026-06-01
• Study Completion: 2027-06-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 80

Inclusion Criteria

-Patients suffered from end stage knee osteoarthritis of grade four according to Kellgren-Lawrence classification in at least one of the three knee compartments, who have an osteoarthritic knees of varus Coronal Plane Alignment of the Knee classification

Exclusion Criteria

1. Any valgus malalignment of the knee joint.
2. Malalignment more than 10° or less than 3° varus of knee joint.
3. Ligamentous laxity of the affected knee (medial or lateral collateral ligaments)
4. any tumors or secondary neoplasia diseases
5. Knee joint infection
6. severe cardiopulmonary dysfunction.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Oxoford knee score	12 months	The Oxford Knee Score is a 12-item patient-reported outcomes specifically designed and developed to assess function and pain after total knee replacement arthroplasty. It is short, reproducible, valid and sensitive to clinically important changes.; Score each question from 0 to 4 with 4 being the best outcome. This method, when summed, produces overall scores running from 0 to 48 with 48 being the best outcome

Secondary Outcome Measures

Name	Time	Method
Knee Injury and Osteoarthritis Outcome Score	24 months	The Knee Injury and Osteoarthritis Outcome Score is a questionnaire designed to assess short and long-term patient-relevant outcomes following knee injury. The questionnaire is self-administered and assesses five outcomes: pain(9 items), symptoms(7 items), activities of daily living(17 items), sport and recreation function(5 items), and knee-related quality of life (4 items). The questionnaire meets basic criteria of outcome measures and can be used to evaluate the course of knee injury and treatment outcome.; A Likert scale is used and all items have five possible answer options scored from 0 (No problems) to 4 (Extreme problems) and each of the five scores is calculated as the sum of the items included.; Scores are transformed to a 0-100 scale, with zero representing extreme knee problems and 100 representing no knee problems as common in orthopaedic scales and generic measures. Scores between 0 and 100 represent the percentage of total possible score achieved.
Forgotten Joint Score	24 months	The Forgotten Joint Score was designed to assess patient outcome in patients undergoing conservative or operative treatment of the knee. This questionnaire shows its strengths in patients with a good level of knee function and a low pain level. It has been designed specifically to reduce ceiling effects commonly associated with many patients reported outcome measures in this patient group, e.g. when assessing short- to mid-term results in total knee arthroplasty patients.; Every question is scored 1 (never) to 5 (mostly) according to the selected response categories. Thus, the raw score ranges from 12 to 60. The raw score is linearly transformed to a 0-100 scale and then reversed to obtain the final score.; Final score = 100 - ((sum(item01 to item12) - 12)/48\*100) For the final 'Forgotten Joint Score -12' a high score indicates good outcome.