MIN Surgery®

Minimal Incision Total Knee Arthroplasty

New Technique in Surgical positioning

Peter M. Bonutti, MD

Bonutti Orthopedic Clinic, Effingham, IL


Materials/Methods


Twenty consecutive patients were evaluated utilizing the suspended leg approach for MIN TKA:      Twelve female, eight male.  Patient ages ranged from 56-87, weight averaged 210 lbs (110 - 270 lbs).

The patient's leg was flexed and suspended over a table . Unique sterile draping technique and surgical heads were utilized and an incision was made two times the patellar length - 6.5-12 cm with the knee in flexion.  VMO split was utilized and the patella was retracted (not everted) laterally using special retractors to expose the joint.

Draping

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Special downsized instrumentation were used to performed extramedullary tibial and intramedullary femoral alignment with an anterior referencing system.

Tibial Cut

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Femoral Cut

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The knee was sequentially flexed and extended to expose either the tibia or the femur and allow appropriate releases. 

With the leg suspended, enhanced exposure of the posterior joint was obtained and simplified retraction of the patella laterally was allowed with reduced damage to the quadriceps mechanism. 

 

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Implant trailing and ligament balancing were especially enhanced in flexion allowing gravity to distract the leg to evaluate true collateral ligament balancing both in flexion / extension and through rotation.  (Note, when the leg is flexed in a traditional leg holder the posterior femur impacts against the posterior tibia and one does not obtain a true anatomic ligament balancing).

Trials

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Tricompartmental Cemented TKA

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The patella is then rotated 90 only in full extension to expose the patella for resurfacing.

Then a tricompartmental total knee replacement (Scorpio - Stryker) was cemented in position, patella tracking and ligament balancing was once again evaluated through range of motion and the knee was closed in flexion.

Incision length averaged 9 cm in extension or 12 cm in knee flexion (range 9.0-14.0 cm).  Tourniquet time averaged 55 minutes.

No exclusions were made based on preoperative ROM, contractures, stiffness, or degree of deformity.


75 Y/O wf   175 lbs.


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