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Official Description

Arthrodesis, metacarpophalangeal joint, with or without internal fixation;

© Copyright 2025 American Medical Association. All rights reserved.

Common Language Description

Arthrodesis of a metacarpophalangeal (MCP) joint is a surgical procedure aimed at fusing the bones of the MCP joint, which is located between the metacarpal bone of the hand and the proximal phalanx of a finger. This procedure is typically indicated for patients suffering from conditions such as arthritis or instability of the MCP joint, which can lead to pain, decreased function, and impaired mobility. The surgery involves making an incision over the MCP joint to access the joint capsule, which is then incised to allow for inspection of the joint surfaces. During the procedure, the articular cartilage from both the metacarpal head and the phalanx is excised to prepare the surfaces for fusion. The metacarpal is then smoothed and reshaped using a bur, ensuring that it fits properly into the base of the phalanx bone. In some cases, internal fixation devices, such as pins or wires, may be utilized to maintain the desired position of the MCP joint until the bones have fused together. After the joint surfaces are prepared and any necessary fixation is applied, the soft tissues are meticulously repaired in layers, and a short arm cast is applied to support the hand during the healing process.

© Copyright 2025 Coding Ahead. All rights reserved.

1. Indications

Arthrodesis of the metacarpophalangeal joint is performed for specific indications, primarily related to joint dysfunction and instability. The following conditions may warrant this surgical intervention:

  • Arthritis - Chronic inflammation of the joint leading to pain and loss of function.
  • Joint Instability - Conditions that result in excessive movement or dislocation of the MCP joint.

2. Procedure

The procedure for arthrodesis of the metacarpophalangeal joint involves several critical steps to ensure successful fusion of the joint surfaces. Each step is essential for achieving the desired outcome of pain relief and improved joint stability.

  • Step 1: Incision - A surgical incision is made over the MCP joint to provide access to the joint capsule. This incision allows the surgeon to reach the underlying structures effectively.
  • Step 2: Joint Capsule Incision - The joint capsule is carefully incised, enabling the surgeon to inspect the joint surfaces for any damage or degeneration that may have occurred.
  • Step 3: Cartilage Excision - The articular cartilage from both the metacarpal head and the phalanx is excised. This step is crucial as it prepares the bone surfaces for direct contact, facilitating the fusion process.
  • Step 4: Bone Reshaping - The metacarpal is smoothed and reshaped using a bur. This reshaping ensures that the metacarpal fits properly into the base of the phalanx, which is vital for achieving a stable fusion.
  • Step 5: Internal Fixation - If necessary, internal fixation devices such as pins or wires are used to maintain the MCP joint in the desired position. This fixation is critical to ensure that the joint remains stable while the fusion occurs.
  • Step 6: Soft Tissue Repair - After the joint surfaces are prepared and any fixation is applied, the soft tissues are repaired in layers. This meticulous repair is important for restoring the integrity of the surrounding tissues.
  • Step 7: Casting - Finally, a short arm cast is applied to support the hand and immobilize the MCP joint during the healing process, allowing for proper fusion of the bones.

3. Post-Procedure

Post-procedure care following arthrodesis of the metacarpophalangeal joint is essential for optimal recovery. Patients can expect to have their hand immobilized in a short arm cast to protect the surgical site and maintain joint stability during the healing process. The duration of casting may vary based on individual healing rates and the surgeon's recommendations. Patients will typically be monitored for signs of complications, such as infection or non-union of the joint. Rehabilitation may be initiated after a period of immobilization, focusing on restoring range of motion and strength in the hand while ensuring that the fusion remains intact.

Short Descr FUSION OF KNUCKLE
Medium Descr ARTHRODESIS METACARPOPHALANGEAL JT W/WO INT FIXJ
Long Descr Arthrodesis, metacarpophalangeal joint, with or without internal fixation;
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) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 0 - Payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
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 5
CCS Clinical Classification 162 - Other OR therapeutic procedures on joints

This is a primary code that can be used with these additional add-on codes.

20705 Add-on Code MPFS Status: Active Code APC N Removal of drug-delivery device(s), intra-articular (List separately in addition to code for primary procedure)
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)
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.
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.
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.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 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.)
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).
81 Minimum assistant surgeon: minimum surgical assistant services are identified by adding modifier 81 to the usual procedure number.
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).
AQ Physician providing a service in an unlisted health professional shortage area (hpsa)
AS Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery
CR Catastrophe/disaster related
F1 Left hand, second digit
F2 Left hand, third digit
F3 Left hand, fourth digit
F4 Left hand, fifth digit
F5 Right hand, thumb
F6 Right hand, second digit
F7 Right hand, third digit
F8 Right hand, fourth digit
F9 Right hand, fifth digit
FA Left hand, thumb
GC This service has been performed in part by a resident under the direction of a teaching physician
SG Ambulatory surgical center (asc) facility service
T5 Right foot, great toe
TA Left foot, great toe
TV Special payment rates, holidays/weekends
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
Date
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Notes
2010-01-01 Changed Code description changed.
Pre-1990 Added Code added.
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