Hip Arthroplasty Vertical Capsular Incision for Stability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Contemporary hip arthroplasty approaches are associated with significant blood loss and impaired joint stability post-surgery, leading to restrictions in patient activity during the early postoperative period, and minimally invasive techniques risk component malpositioning and early loosening due to limited exposure.

Innovation Solution

The Modified anatomical direct lateral approach, which preserves the iliofemoral ligament and restores the joint capsule through a vertical capsular incision anterior to the femoral shaft, avoiding trochanteric osteotomy and ensuring secure reattachment of the abductor flap, thereby enhancing joint stability and reducing blood loss.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If standard contemporary approaches for hip arthroplasty are used, then joint access and exposure are adequate, but blood loss is significant and joint stability is impaired post-surgery

Engineering Contradiction:

Improvejoint exposureVSAvoidblood loss

Core Design Contradiction:

Area of stationary objectVSLoss of substance

Solution Approach 1:

The surgical approach is segmented into specific muscle splits: splitting the gluteus medius muscle and the underlying tendinous part of gluteus minimus muscle along their fibers, while preserving the vastus lateralis muscle by curving the fascial incision along the posterior aspect of the greater trochanter. This selective segmentation allows adequate exposure while minimizing damage to blood supply.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The vertical capsular incision is made at a specific location anterior to the femoral shaft, starting from the basicervical line and extending proximally along the longitudinal body axis, oriented parallel to the iliofemoral ligament fibers. This localized precision ensures the iliofemoral ligament remains intact while providing adequate capsular access.

Inventive Principle:

Principle #3Local quality

2Area of stationary object

If standard contemporary approaches for hip arthroplasty are used, then joint access is adequate, but joint stability is impaired leading to dislocation risks

Engineering Contradiction:

Improvejoint exposureVSAvoidjoint stability

Core Design Contradiction:

Area of stationary objectVSReliability

Solution Approach 1:

The joint capsule is temporarily opened (discarded) during surgery through the vertical capsular incision to allow implant insertion and positioning, then restored (recovered) by stitching the capsule at the end of the procedure. The iliofemoral ligament is preserved throughout, providing continuous stability. This recovery of the capsule with preserved ligamentous structures ensures joint stability while allowing necessary surgical access.

Inventive Principle:

Principle #34Discarding and recovering

3Loss of substance

If minimally invasive surgical techniques are used, then blood loss is reduced and dislocation risk is decreased, but component malpositioning and early loosening occur due to limited exposure

Engineering Contradiction:

Improveblood lossVSAvoidcomponent positioning accuracy

Core Design Contradiction:

Loss of substanceVSManufacturing precision

Solution Approach 1:

The approach uses a moderate fascial incision that curves along the posterior aspect of the greater trochanter and ends at its lower border, which is more extensive than minimally invasive techniques but less than standard approaches. This partial action provides sufficient exposure for accurate bone preparation and component positioning while maintaining the benefits of reduced soft tissue disruption and blood loss.

Inventive Principle:

Principle #16Partial or excessive action

4Loss of substance

If tranexamic acid is administered to decrease blood loss, then perioperative bleeding is reduced, but it cannot be used in patients with high thrombotic risk or cardiovascular disease

Engineering Contradiction:

Improveblood lossVSAvoidpatient eligibility

Core Design Contradiction:

Loss of substanceVSAdaptability or versatility

Solution Approach 1:

The surgical technique itself provides hemostasis through meticulous dissection and preservation of blood supply to the abductor muscles. By splitting muscles along their fibers and preserving the vascular supply, the technique achieves reduced blood loss through its own design rather than relying on pharmacological agents like tranexamic acid, making it applicable to all patients regardless of thrombotic risk.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS11273054B2Methods for hip replacement with anterior vertical capsule incision-modified anatomical direct lateral approach (Vitosha approach)

Publication Date: 2022.03.15 EKTA SOFIA LTD

AI summary

The Modified anatomical direct lateral approach (Vitosha approach), a novel approach in hip arthroplasty, preserving the iliofemoral ligament and restoring the joint capsule, providing higher initial joint stability and easier rehabilitation without the need for post-operative patients' dislocation precautions is provided. The fascial incision curves along the posterior aspect of the greater trochanter and ends at its lower border, preventing a split of vastus lateralis muscle. The anterolateral periosteal layer which conjoins the gluteus medius and vastus lateralis muscles is sharply elevated from the greater trochanter. Gluteus medius muscle and the underlying gluteus minimus are split along its fibers and retracted anteriorly. A vertical capsular incision is made anterior to the femoral shaft, starting from the basicervical line and extending proximally along the longitudinal body axis, with the iliofemoral ligament fibers remained intact.