Is procedure code 27165, incision/fixation of femur, and 2 inpatient days per BLOS medically necessary for a 17-year-old female with polyostotic fibrous dysplasia?

Medical Necessity Determination for CPT 27165 and 2-Day Inpatient Stay

Yes, procedure code 27165 (intertrochanteric or subtrochanteric osteotomy with internal fixation) and a 2-day inpatient stay are medically necessary for this 17-year-old female with polyostotic fibrous dysplasia of the left femur presenting with progressive hip pain, limb length inequality, and documented bony deformity requiring surgical correction.

Rationale for Medical Necessity

Clinical Indication Met

The patient meets established criteria for surgical intervention in fibrous dysplasia based on symptomatic presentation, functional impairment, and risk of pathologic fracture. 1

• The patient has documented polyostotic fibrous dysplasia with anterior bowing of the femoral shaft and significant limb length inequality causing functional gait abnormality 1
• Progressive hip pain over the past week with antalgic gait represents symptomatic disease requiring intervention 1
• CT imaging confirms extensive fibrous dysplasia involving the proximal and distal femur without current fracture but with deformity requiring correction 1

Surgical Timing and Approach

Surgery is indicated for correction of deformity and prevention of pathologic fracture in this adolescent patient approaching skeletal maturity. 1, 2

• At age 17, the patient is near skeletal maturity, making this an optimal time for definitive osteotomy rather than guided growth techniques which require 2-3 years of remaining growth potential 3
• The presence of anterior bowing and mechanical axis deviation creates abnormal forces across the hip joint that increase fracture risk and accelerate joint degeneration 1
• Femoral shortening with intramedullary rod fixation addresses both the deformity and limb length discrepancy while providing internal stabilization to prevent pathologic fracture 4

Specific Surgical Considerations for Fibrous Dysplasia

Intramedullary fixation is the preferred technique for femoral fibrous dysplasia requiring osteotomy. 4

• Multiple osteotomies with intramedullary nail fixation (such as the Zickel nail technique described in the literature) provide definitive control of deformity and prevent recurrent fracture in polyostotic fibrous dysplasia of the proximal femur 4
• This approach allows patients to return to normal activities with reduced morbidity compared to conventional methods 4
• Cortical grafts are preferred over cancellous grafts if bone grafting is needed due to superior physical qualities of remodeled cortical bone in fibrous dysplasia 1

Medical Optimization Prior to Surgery

The patient appropriately underwent CT imaging to rule out impending fracture before proceeding with elective surgery. 1

• The CT scan confirmed no acute fracture or impending fracture, making this an appropriate elective rather than emergent procedure 1
• The patient has been using crutches for weight-bearing protection, which is appropriate conservative management while awaiting surgery 1
• Bisphosphonate therapy may be considered perioperatively to improve bone quality and reduce fracture risk, though this is adjunctive rather than a substitute for surgery 1, 2

Inpatient Stay Justification

A 2-day inpatient stay is medically appropriate for this complex orthopedic procedure in an adolescent patient. 5

• Femoral osteotomy with intramedullary fixation requires general anesthesia and carries risks including fat embolism syndrome, which necessitates immediate postoperative monitoring 5
• Early mobilization under supervised physical therapy is essential to prevent complications and ensure proper weight-bearing progression 5
• Pain management for major long bone surgery typically requires 24-48 hours of parenteral analgesia before transitioning to oral medications 5
• The patient requires monitoring for early surgical complications including compartment syndrome, neurovascular compromise, and fat embolism 5

Important Clinical Caveats

Several key considerations must be addressed perioperatively:

• Ensure adequate hydration and maintain systolic blood pressure within 20% of baseline during surgery to reduce fat embolism risk 5
• Administer supplemental oxygen for at least 24 hours postoperatively 5
• Use thorough washing and drying of the femoral canal before intramedullary device insertion to minimize fat embolism 5
• Plan for long-term follow-up as fibrous dysplasia can progress and refracture may occur even years after successful union 1, 2
• Consider calcium, vitamin D, and phosphorus supplementation given the association of polyostotic fibrous dysplasia with renal phosphate wasting 2

Procedure Code Appropriateness

CPT 27165 accurately describes the planned surgical intervention. 1, 4

• The code specifically covers intertrochanteric or subtrochanteric osteotomy with internal fixation, which matches the described femoral shortening with intramedullary rod procedure 4
• This is distinct from the previously certified code 27161, as the current procedure involves osteotomy with fixation rather than simple fixation alone 4