Orthopedic Coding Alert

Editors Note: Experts in orthopedic coding agree that successful coding in this specialty requires a sound knowledge of medical terminology, the procedures involved and correct CPT codes and diagnostic coding. Our goal is to present actual orthopedic coding cases within the context of the medical terminology and procedures. If you have a case you would like to submit for consideration, please send it via fax, email, or mail.

Case Description

A 74-year-old woman with osteoporosis falls while walking her dog and is taken to the emergency department where she is found to have a subcapital fracture of the right hip. An orthopedic surgeon is called, and the woman is admitted to the hospital and placed in Bucks traction. The next afternoon, she is taken to surgery where an ORIF hemiarthroplasty is successfully performed. The woman is returned to the orthopedic floor of the hospital, but several hours post surgery, in a state of confusion, she attempts to get out of her hospital bed. She crawls past the side rails and slips off the edge of the bed, falling on the repaired hip. Upon examination, she is now found to have posterior dislocation of the prosthesis and is returned to surgery. Under general anesthesia, the orthopedist externally manipulates the prosthesis back into place. The coder receives a surgical report that requires the coding procedures for both the fracture and dislocation.

Terminology and Procedures

The hip fracture, a familiar orthopedic problem, is most often found in white females over 50 years of age. In fact, its interesting to note that 90 percent of all fractures occur in white women aged 70 years and over. Osteoporosis (a general term describing a reduction in bone mass) related hip fractures are a severe economic burden to society, costing an estimated $8 billion per year in the United States.

This case describes a subcapital fracture (820.09), which is a general term to describe a breaking off of the femoral head or top of the femur. The hip joint is a typical example of a ball-and-socket joint, the acetabulum forming the socket and the femoral head the ball. This type of joint combines stability, in all normal positions, with a good range of movement.

Arthroplasty is the general operative procedure that reconstructs both articulating surfaces of a joint. In a total hip replacement (27130), both the ball and socket are completely replaced. In the hemiarthroplasty (27125 or 27236), the focus is on the replacement or reconstruction of the ball even though an acetabular cup may also be placed. Prosthesis is a term used to describe the artificial or replaced part. ORIF is a common orthopedic acronym that stands for open reduction internal fixation.

In a dislocation there is no breaking of bones, instead it is a displacement of the bone from its normal place in a joint. In hip dislocations the direction of the displaced femur head is described as being posterior, obturator or anterior. Dislocations can be relocated under local or general anesthesia and by way of open or closed procedures.

Coders Notebook

As the coder approaches this operative report, there are a number of coding errors that may result in less than full reimbursement or require time-consuming resubmissions. First, the coder needs to recognize that two operative procedures have been performed on this patient. While both were done on the same date, you will want to maximize reimbursement for all the work invested in this patient.

There are two codes that are commonly confused when reporting a hemiarthroplasty. The code 27125 (hemiarthroplasty, hip, partial [e.g., femoral stem prosthesis, bipolar]) should be used for a routine partial hip replacement, while 27236 (open treatment of femoral fracture, proximal end, neck, internal fixation or prosthetic replacement [direct fracture exposure]) is to be used when there is a subcapital fracture and the head of the femur is either reattached or a new prosthetic head is used. In this case 27236 is the correct code.

The diagnosis code for the hip fracture is 820.09 (fracture of neck of femur, subcapital), although there are many types of hip fractures, such as: neck of femur, head of femur, intracapsular, epiphysis, base of neck and transcervical or midcervical. The diagnosis code for the later dislocation can be tricky. The diagnosis code for a dislocated hip is 835 with the coder needing to know if it was open or closed and the direction (posterior, or anterior) of the dislocation. This would seem to be the right code, but in this case, the dislocation is actually a dislocation of the prosthesis, which is considered a mechanical complication of an orthopedic device. Therefore, the diagnosis code for the dislocation would be 996.4 (mechanical complication of internal orthopedic device, implant and graft).

Once you get the right diagnosis code for the dislocation or mechanical complication, the procedure code becomes clear. You need a code for a post hip arthroplasty that has been displaced and done under general anesthesia. There are a number of codes for hip dislocation from 27250-27266 that cover every type of dislocation (congenital, traumatic and non-traumatic) and treatment. The one that applies in this case is 27266 (closed treatment of post hip arthroplasty dislocation requiring regional or general anesthesia).

Finally, since this patient was returned to surgery during the postoperative period of the hemiarthroplasty, the treatment for the dislocation will need to be appended with the 78 modifier. The CPT states: When this subsequent procedure is related to the first, and requires the use of the operating room, it may be reported by adding the modifier 78 to the related procedure

With all of this in mind, coding for this procedure would appear as follows:

Diagnosis Codes:

  
1. 820.09
2. 996.4    

Procedures: Diagnosis:

27236    		1
27266-78  		1, 2

Article contributors: Expert advice for this case study was provided by the following sources: Jeri Harris, CPC, CPC-H, an orthopedic coding consultant from Charleston, SC; Thomas Kent, CMM, Principal, Kent Medical Management, Dunkirk, MD; Aluisio, Christensen, Urbaniak, Orthopedics, Second Edition, Williams & Wilkins, Baltimore: 1998.