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Arthroplasty of the knee, specifically CPT® Code 27446, refers to a surgical procedure known as a partial knee replacement or unicompartmental knee replacement. This operation is indicated for patients suffering from localized knee joint issues, typically affecting either the medial or lateral compartment of the knee. During the procedure, a surgical incision is made over the appropriate compartment, which allows the surgeon to access the knee joint directly. The choice of incision location—either on the medial or lateral side—depends on which compartment is being replaced. In some cases, an incision may be made on the anterior aspect of the knee to facilitate a more comprehensive exploration of the entire joint. The procedure involves careful inspection of the joint capsule and the compartments of the knee, followed by the exposure of the distal femur. A cutting guide is utilized to ensure that the bone is cut accurately, maintaining the proper alignment of the joint and leg angles. The preparation of the tibial surface is performed in a similar manner, ensuring that both the femoral and tibial components of the prosthesis fit securely. The prosthetic components can be either cemented or uncemented, with the choice depending on the specific requirements of the patient and the surgeon's preference. After the components are placed, the range of motion is assessed to ensure functionality before the soft tissues and skin are meticulously repaired in layers. This procedure aims to relieve pain and restore mobility in patients with degenerative joint disease or other knee-related conditions affecting a single compartment of the knee joint.
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The procedure of knee arthroplasty, specifically CPT® Code 27446, is indicated for patients experiencing specific conditions affecting the knee joint. These indications include:
The procedure for CPT® Code 27446 involves several critical steps to ensure a successful partial knee replacement:
Post-procedure care following a knee arthroplasty involves monitoring the patient for any complications and ensuring proper recovery. Patients are typically advised to engage in physical therapy to regain strength and mobility in the knee. Pain management strategies are implemented to alleviate discomfort during the recovery phase. The expected recovery time may vary, but patients can generally anticipate a gradual return to normal activities, with follow-up appointments scheduled to assess the healing process and the functionality of the knee joint. It is essential for patients to adhere to their rehabilitation program and follow the surgeon's instructions to optimize outcomes and minimize the risk of complications.
| Short Descr | REVISION OF KNEE JOINT | Medium Descr | ARTHRP KNEE CONDYLE&PLATEAU MEDIAL/LAT CMPRT | Long Descr | Arthroplasty, knee, condyle and plateau; medial OR lateral compartment | Status Code | Active Code | Global Days | 090 - Major Surgery | PC/TC Indicator (26, TC) | 0 - Physician Service Code | Multiple Procedures (51) | 2 - Standard payment adjustment rules for multiple procedures apply. | Bilateral Surgery (50) | 1 - 150% payment adjustment for bilateral procedures applies. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 2 - Payment restriction for assistants at surgery does not apply to this procedure... | Co-Surgeons (62) | 1 - Co-surgeons could be paid, though supporting documentation is required... | Team Surgery (66) | 0 - Team surgeons not permitted for this procedure. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | APC Status Indicator | Hospital Part B services paid through a comprehensive APC | ASC Payment Indicator | Device-intensive procedure added to ASC list in CY 2008 or later; paid at adjusted rate. | Type of Service (TOS) | 2 - Surgery | Berenson-Eggers TOS (BETOS) | P3C - Major procedure, orthopedic - Knee replacement | MUE | 1 | CCS Clinical Classification | 152 - Arthroplasty knee |
| RT | Right side (used to identify procedures performed on the right side of the body) | LT | Left side (used to identify procedures performed on the left side of the body) | AS | Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery | GC | This service has been performed in part by a resident under the direction of a teaching physician | 82 | Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s). | 80 | Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s). | SG | Ambulatory surgical center (asc) facility service | 50 | Bilateral procedure: unless otherwise identified in the listings, bilateral procedures that are performed at the same session, should be identified by adding modifier 50 to the appropriate 5 digit code. note: this modifier should not be appended to designated "add-on" codes (see appendix d). | 51 | Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d). | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | 79 | Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.) | 22 | Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service. | 52 | Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use). | 56 | Preoperative management only: when 1 physician or other qualified health care professional performed the preoperative care and evaluation and another performed the surgical procedure, the preoperative component may be identified by adding modifier 56 to the usual procedure number. | 58 | Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78. | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | 62 | Two surgeons: when 2 surgeons work together as primary surgeons performing distinct part(s) of a procedure, each surgeon should report his/her distinct operative work by adding modifier 62 to the procedure code and any associated add-on code(s) for that procedure as long as both surgeons continue to work together as primary surgeons. each surgeon should report the co-surgery once using the same procedure code. if additional procedure(s) (including add-on procedure(s) are performed during the same surgical session, separate code(s) may also be reported with modifier 62 added. note: if a co-surgeon acts as an assistant in the performance of additional procedure(s), other than those reported with the modifier 62, during the same surgical session, those services may be reported using separate procedure code(s) with modifier 80 or modifier 82 added, as appropriate. | 74 | Discontinued out-patient hospital/ambulatory surgery center (asc) procedure after administration of anesthesia: due to extenuating circumstances or those that threaten the well being of the patient, the physician may terminate a surgical or diagnostic procedure after the administration of anesthesia (local, regional block(s), general) or after the procedure was started (incision made, intubation started, scope inserted, etc). under these circumstances, the procedure started but terminated can be reported by its usual procedure number and the addition of modifier 74. note: the elective cancellation of a service prior to the administration of anesthesia and/or surgical preparation of the patient should not be reported. for physician reporting of a discontinued procedure, see modifier 53. | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | 78 | Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.) | 81 | Minimum assistant surgeon: minimum surgical assistant services are identified by adding modifier 81 to the usual procedure number. | AG | Primary physician | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | CG | Policy criteria applied | CR | Catastrophe/disaster related | GW | Service not related to the hospice patient's terminal condition | KX | Requirements specified in the medical policy have been met | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | X4 | Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
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