Knee Arthroplasty Surgery Operative report

Scenario 1

Patient Name: ABC

Medical Record #: 12345

Date of Surgery: 01 Jan 2025

Surgeon: Medycoding

Assistant: Medicoder

Anesthesia: Spinal anesthesia with adductor canal block Position: Supine

PREOPERATIVE DIAGNOSIS: Medial compartment osteoarthritis, right knee POSTOPERATIVE DIAGNOSIS : Medial compartment osteoarthritis, right knee

PROCEDURE PERFORMED : Right medial unicompartmental knee arthroplasty

INDICATIONS :The patient is a 45-year-old male with severe medial compartment osteoarthritis of the right knee, refractory to conservative management including physical therapy, NSAIDs, activity modification, bracing, and intra-articular injections. Radiographs demonstrated isolated medial compartment bone-on-bone degenerative changes with preservation of the lateral and patellofemoral compartments. Ligamentous examination confirmed intact ACL and correctable varus deformity. After discussion of risks, benefits, and alternatives, the patient elected to proceed with unicompartmental knee arthroplasty.

PROCEDURE IN DETAIL :The patient was brought to the operating room and placed supine on the operating table. After successful spinal anesthesia and regional block, prophylactic IV antibiotics were administered. A well-padded tourniquet was applied to the proximal right thigh. The right lower extremity was prepped and draped in the usual sterile fashion. A surgical time-out was performed confirming patient identity, procedure, and laterality. The limb was exsanguinated with an Esmarch bandage, and the tourniquet was inflated to appropriate pressure.

Surgical Approach

A longitudinal skin incision approximately 6–8 cm in length was made over the anteromedial aspect of the right knee. Dissection was carried sharply through subcutaneous tissue. Hemostasis was achieved with electrocautery. A medial parapatellar arthrotomy was performed, extending from the superior pole of the patella to just medial to the tibial tubercle. The patella was subluxated laterally without eversion to expose the medial compartment.

Intraoperative Assessment Examination confirmed: Full-thickness cartilage loss in the medial femoral condyle and medial tibial plateau Intact anterior cruciate ligament Preserved lateral compartment cartilage Minimal degenerative changes in the patellofemoral joint The findings confirmed suitability for medial unicompartmental replacement.

Tibial Preparation An extramedullary alignment guide was positioned referencing the tibial shaft and ankle center. The proximal tibial resection level was set to remove minimal bone while restoring native joint line and slope. A sagittal cut was made medial to the tibial spine to define the resection boundary. The proximal tibial cut was then performed using an oscillating saw. The resected bone fragment was removed. The tibial surface was sized, and preparation was performed for the tibial component using appropriate keel punch instrumentation.

Femoral Preparation Attention was turned to the medial femoral condyle. Intramedullary alignment was not required for this system. Femoral sizing guides were placed referencing the posterior condyle and distal femoral anatomy. The distal femoral resection was performed followed by posterior and chamfer cuts using system-specific cutting guides. Trial femoral components were inserted to assess fit and alignment.

Trialing

Trial tibial and femoral components were inserted along with trial polyethylene inserts. The knee was taken through a full range of motion.

Assessment demonstrated: Excellent flexion and extension balance Appropriate ligamentous tension Correction of varus deformity Stable tracking No impingement The selected polyethylene thickness restored native alignment and stability. Implantation The bone surfaces were thoroughly irrigated and dried. Polymethylmethacrylate bone cement was mixed under vacuum. The final implants placed were:

Femoral Component: Oxford Partial Knee medial femoral component, right side, size Medium Tibial Component: Oxford Partial Knee medial tibial tray, right side, size C Polyethylene Insert: Mobile-bearing polyethylene insert, 4 mm thickness Cement was applied to the prepared tibial and femoral surfaces.

The tibial component was implanted first and impacted into position with excess cement removed. The femoral component was then cemented into place. Final polyethylene insert was placed after cement curing. All excess cement was meticulously removed. Final range of motion and stability were reassessed and found to be satisfactory. Closure The wound was irrigated with copious normal saline solution. The tourniquet was deflated, and hemostasis was achieved. The arthrotomy was closed with interrupted absorbable sutures. Subcutaneous tissues were closed in layers. Skin was closed with staples or subcuticular sutures. Sterile dressing was applied.

ESTIMATED BLOOD LOSS Approximately 75 mL

TOURNIQUET TIME [20] minutes

SPECIMENS None

COMPLICATIONS None

CONDITION The patient tolerated the procedure well and was transferred to the recovery room in stable condition. Sponge, needle, and instrument counts were correct at the completion of the case.

Check your Answer

CPT : 27446-RT

ICD : M17.11

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Scenario 2

Patient Name: ABC

Medical Record #: 12345

Date of Surgery: 02 Jan 2025

Surgeon: Medycoding

Assistant: Medicoder

Anesthesia: Spinal anesthesia with adductor canal block Position: Supine

PREOPERATIVE DIAGNOSIS: Failed right total knee arthroplasty

POSTOPERATIVE DIAGNOSIS : Failed right total knee arthroplasty

PROCEDURE PERFORMED : Revision right total knee arthroplasty

INDICATIONS :The patient is status post right total knee arthroplasty with persistent pain, instability, and radiographic evidence of component failure consistent with a failed total knee replacement. Conservative management was unsuccessful. After discussion of risks, benefits, and alternatives, the patient elected to proceed with revision right total knee arthroplasty.

DESCRIPTION OF PROCEDURE

The patient was brought to the operating room and placed supine on the operating table. Spinal anesthesia was administered without complication. A well-padded tourniquet was applied to the proximal right thigh. The right lower extremity was prepped and draped in the usual sterile fashion. A surgical timeout was performed confirming correct patient, procedure, and operative site.

The limb was exsanguinated and the tourniquet inflated. A midline longitudinal incision was made through the prior surgical scar. Dissection was carried sharply through the subcutaneous tissue to the extensor mechanism. A medial parapatellar arthrotomy was performed, and the patella was everted to expose the knee joint.

Upon entering the joint, inspection revealed evidence of component loosening and polyethylene wear. There was synovial hypertrophy but no gross purulence. The existing polyethylene insert was removed first. The femoral component was carefully exposed and removed using flexible osteotomes and extraction instruments with preservation of bone stock. The tibial component was similarly loosened and removed with care to minimize bone loss.

All residual cement was meticulously cleared from the distal femur and proximal tibia. The bone surfaces were debrided and prepared for revision implantation.

Attention was turned to the distal femur. Sequential reaming and freshening cuts were performed to establish proper alignment and rotation. Trial femoral components were placed and assessed for fit and stability.

The proximal tibia was then prepared. The tibial surface was recut to create a stable platform. Due to concern for bone loss and alignment, a stemmed tibial component was selected to enhance fixation and stability. Trial tibial components were inserted, and appropriate rotation was confirmed.

Trial reduction was performed using provisional polyethylene inserts. Range of motion was assessed from full extension to flexion. Stability was evaluated in varus and valgus stress as well as anterior and posterior drawer testing. Patellar tracking was assessed and found to be satisfactory.

After confirming appropriate sizing, alignment, and stability, all trial components were removed. The bony surfaces were irrigated with pulsatile lavage and dried.

Polymethylmethacrylate bone cement was prepared and applied to the tibial and femoral surfaces. The definitive tibial component with stem extension was implanted and held in position until cement polymerization. The femoral component was then cemented into place. A 17 mm polyethylene insert was locked into the tibial tray. The knee was again taken through a full range of motion and demonstrated excellent stability and alignment.

The tourniquet was released. Hemostasis was achieved with electrocautery. The wound was irrigated thoroughly. A closed-suction drain was placed.

The arthrotomy was closed with interrupted absorbable sutures. Subcutaneous tissues were reapproximated in layers. The skin was closed with staples. A sterile dressing was applied.

The patient tolerated the procedure well. Distal pulses were intact, and the foot was warm and well perfused at the conclusion of the case. The patient was transferred to the recovery room in stable condition.

Check your Answer

CPT : 27487-RT

ICD : T84.092A

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Scenario 3

Patient Name: ABC

Medical Record #: 12345

Date of Surgery: 03 Jan 2025

Surgeon: Medycoding

Assistant: Medicoder

Anesthesia: Spinal anesthesia with adductor canal block

Position: Supine

PREOPERATIVE DIAGNOSIS: End-stage osteoarthritis of the right knee

POSTOPERATIVE DIAGNOSIS : End-stage osteoarthritis of the right knee

PROCEDURE PERFORMED : Primary right total knee arthroplasty

INDICATIONS :The patient is a 79-year-old female with severe tricompartmental osteoarthritis of the right knee, characterized by complete cartilage loss, bone-on-bone articulation, osteophyte formation, stiffness, and debilitating pain. Conservative treatment including medications, injections, and physical therapy failed to provide relief. Surgical intervention was recommended.

DESCRIPTION OF PROCEDURE

The patient was positioned supine under appropriate anesthesia. A tourniquet was applied to the proximal thigh. The right lower extremity was prepped and draped in sterile fashion.

A midline anterior incision was made over the knee. Dissection was carried through subcutaneous tissue to the extensor mechanism. A medial parapatellar arthrotomy was performed. The patella was everted, exposing the knee joint. Significant degenerative changes were observed including complete cartilage erosion, subchondral bone exposure, and prominent osteophytes.

The distal femur was prepared using intramedullary alignment guides, and the distal femoral cut was performed. The proximal tibia was cut using extramedullary alignment guides. Osteophytes were removed. The patella was resurfaced by resecting the articular surface.

Trial femoral and tibial components were inserted. Alignment, rotation, and ligament balance were assessed. Intraoperative imaging confirmed appropriate positioning.

The initial tibial component alignment was deemed suboptimal. The component was removed, and further preparation was performed. A stemmed tibial component was selected to improve fixation and alignment.

After confirming satisfactory alignment and stability, the final implants from the Zimmer NexGen Total Knee System were cemented into place, including the femoral component, tibial component with stem extension, polyethylene insert (17 mm), and patellar component.

The knee was taken through a full range of motion and demonstrated excellent tracking and stability.

The tourniquet was released and hemostasis achieved. A drain was placed. The wound was closed in layers and sterile dressing applied.

Postoperative examination confirmed intact distal perfusion. Postoperative radiographs demonstrated satisfactory alignment and component positioning.

The patient was transferred to recovery in stable condition.

Check Answer

CPT : 27447-RT

ICD : M17.11