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The procedure described by CPT® Code 27331 refers to an arthrotomy of the knee, which is a surgical intervention involving a skin incision made over the knee joint. This procedure allows for direct access to the knee joint, enabling the surgeon to explore the joint cavity, perform a biopsy, or remove any loose or foreign bodies that may be present. During the operation, the surgeon dissects through the surrounding tissues to expose the joint capsule, which is then opened to gain access to the interior of the knee joint. Once the joint is accessed, it is typically flushed with a saline solution to clear away any debris that may be present, ensuring a clean working environment for examination. The surgeon thoroughly inspects the joint for signs of injury or disease, which may include conditions such as arthritis or other joint disorders. If necessary, a synovial biopsy may be performed, where samples of the synovial tissue—responsible for producing synovial fluid—are collected for further laboratory analysis. This tissue can become inflamed due to various conditions, including rheumatoid arthritis. After the exploration and any necessary interventions, such as the removal of loose or foreign bodies, the knee joint is flushed again with saline, and the incision is meticulously closed in layers to promote proper healing.
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The procedure described by CPT® Code 27331 is indicated for various conditions affecting the knee joint. These may include:
The procedure for CPT® Code 27331 involves several critical steps to ensure thorough exploration and treatment of the knee joint.
Post-procedure care following an arthrotomy of the knee includes monitoring for signs of infection, managing pain, and ensuring proper healing of the incision. Patients may be advised to rest the knee and limit weight-bearing activities for a specified period. Follow-up appointments are typically scheduled to assess recovery and discuss the results of any biopsies or laboratory analyses performed during the procedure. Rehabilitation exercises may be recommended to restore range of motion and strength in the knee joint as healing progresses.
| Short Descr | EXPLORE/TREAT KNEE JOINT | Medium Descr | ARTHRT KNE W/JT EXPL BX/RMVL LOOSE/FB | Long Descr | Arthrotomy, knee; including joint exploration, biopsy, or removal of loose or foreign bodies | 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 | Surgical procedure on ASC list in CY 2007; payment based on OPPS relative payment weight. | Type of Service (TOS) | 2 - Surgery | Berenson-Eggers TOS (BETOS) | P3D - Major procedure, orthopedic - other | MUE | 1 | CCS Clinical Classification | 160 - Other therapeutic procedures on muscles and tendons |
| 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. | RT | Right side (used to identify procedures performed on the right side of the body) | 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. | 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). | 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. | 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.) | 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.) | 80 | Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s). | 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). | AG | Primary physician | 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 | LT | Left side (used to identify procedures performed on the left side of the body) | SG | Ambulatory surgical center (asc) facility service | TR | School-based individualized education program (iep) services provided outside the public school district responsible for the student | 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 | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | 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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| Pre-1990 | Added | Code added. |
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