The triangular fibrocartilage complex (TFCC) may be a load-bearing structure between the lunate, triquetrum, and ulnar head. The function of the Triangular Fibrocartilage Complex (TFCC) is to act as a stabilizer for the ulnar aspect of the wrist joint. The TFCC is in danger of either acute or chronic degenerative injury. Forced ulnar deviation and positive ulnar variation carry relation to injuries to the TFCC. Patients with TFCC injury will present with ulnar-sided wrist pain which will present with clicking or point tenderness between the pisiform and therefore the ulnar head. MRI imaging is beneficial as a preliminary diagnostic tool; arthroscopy is the diagnostic gold standard. Treatment options include conservative therapies like rest, NSAIDs, corticosteroid injections, and operative management. Staging The Palmer Classification is employed to categorize TFCC injuries. Class 1 is traumatic, and sophistication 2 is degenerative. All type 2 lesions can potentially accompany positive ulnar variance. Each class is further subclassified:
- 1A: The central aspect of the Triangular Fibrocartilage Complex (TFCC)/triangular fibrocartilage disc is perforated. Since the radioulnar ligaments are intact, these are stable injuries. 1B: Injury of the ulnar attachment of the triangular fibrocartilage disc. This injury is noncommunicating on arthrography.
- 1C: Distal disruption of the TFCC. during this case, there’s a detachment of the volar lunotriquetral and ulnolunate ligaments from the carpal attachment.
- 1D: Injury to the radial attachment of the triangular fibrocartilage disc. These injuries are communicated on MR arthrography. 2A: Degenerative changes of the triangular fibrocartilage disc without proven perforation.
- 2B: Grade 2A with the extra presence of chondromalacia of the cartilage on the articular surface.
- 2C: Full-thickness perforation of the triangular fibrocartilage disc.
- 2D: Any of the features in 2A through 2C plus lunotriquetral ligament tear.
- 2E: Grade 2D with the extra presence of ulnocarpal arthritis.
Causes
- Causes TFCC injury often occurs when a load is compressed on the TFCC while the wrist is in ulnar deviation. The most common causes of forced ulnar deviation include swinging a racket or a bat. TFCC injury is additionally related to positive ulnar variance; this is often when the articular surface of the ulna is more distal than the articular surface of the radius. Positive ulnar variance is usually thanks to prior surgery or prior fracture. Pathophysiology Anatomically the TFCC includes the triangular fibrocartilage disc, extensor carpi ulnaris tendon subsheath, lunotriquetral and ulnolunate ligaments, dorsal and volar distal radioulnar ligaments, meniscal homolog, and therefore the ulnocarpal collateral ligament. The triangular fibrocartilage disc attachment on the radial side is to cartilage, making this weaker than the ulnar side’s bony attachment.[3] Positive ulnar variation can leave the TFCC susceptible to injury. Ulnar variation will decrease with supination movement and increase with pronation. Small changes in ulnar length are shown to possess substantial effects on the quantity of load to the ulna.[4] The extensor carpi ulnaris relies on the TFCC for movement, and thus alteration of the motion of the extensor carpi ulnaris may cause abnormal force through the TFCC, predisposing it to injury.
Histopathology
The histopathology of the components of the TFCC is often weakened as follows[6]:
Triangular fibrocartilage disc: fibrocartilage with blood vessels on the ulnar aspect; otherwise, this structure is avascular
Extensor carpi ulnaris tendon sub-sheath: a mixture of loose and tight parallel collagen
Ulnotriquetral and ulnolunate ligaments: a mixture of loose and tight parallel collagen. The ulnolunate has fewer elastic fibers than the ulnotriquetral
Dorsal and volar distal radioulnar ligaments: parallel collagen bundles
Meniscal homolog: the bulk consists of loose animal tissue
History and Physical
Patients will complain of ulnar-sided wrist pain that always gets worse with activity. There can also be a weakness within the grip, instability, or clicking. There are some elements of history that will occur in conjunction with individual sports. for instance, baseball-specific acute injuries are often thanks to forced wrist extension while doing a head-first slide or when a hitter attempts to hit an indoor pitch and gets “jammed.” Chronic injury can occur in baseball players as a result of the heavy load placed on the wrist during the swing. These athletes can sustain TFCC injuries albeit they are doing not have positive ulnar variance.[7]
If patients have distal radioulnar joint (DRUJ) instability, this is often related to weakness in pronation and supination, which can even be a feature with TFCC injury.[8]
On exam, palpation of the TFCC is best with the wrist in pronation. it’s between the flexor carpi ulnaris, ulnar styloid, and os pisiform. Several physical exam tests can suggest the diagnosis of TFCC injury. These include:
TFCC compression test: forearm within the neutral position with ulnar deviation reproduces symptoms
TFCC stress test: applying a force across the ulna with the wrist in ulnar deviation reproduces symptoms
Press test: Patient lifts themselves out of a chair using the wrists in an extended position. Pain indicates a positive test.
Supination test: The patient grabs the underside of a table with the forearms supinated; this causes a load on the TFCC and dorsal impingement, which can cause pain if there’s a peripheral, dorsal tear.
Piano key test: Place both hands on an exam table and press the palms on the table. If the distal ulna is prominent on the affected side, this means distal radioulnar joint instability, which may have associations with TFCC injury. If the palms are relaxed and therefore the ulnar head goes back to normal position, this is often a positive test.
Grind test: Compress the radius and ulna and have the patient rotate the forearm. Pain could indicate a degenerative process.
Initial workup typically starts with a radiograph to guage for fracture and assess for ulnar variance. subsequent step will often be to urge an MRI with or without an arthrogram. Recent data suggest MR arthrogram is minimally better but arguably not worth doing rather than MRI given the increased discomfort and price related to MRA.[9] If MR is unavailable or contraindicated, a CT are often an option, although the sensitivity is a smaller amount than MRI. Arthroscopy is that the most accurate means by which to diagnose TFCC injury.
Determining if the lunotriquetral ligament is unbroken or torn is crucial to guide treatment options; this will be via radiograph by trying to find a volar tilt of the scaphoid and lunate. Alternatively, an arthrogram showing communication of contrast or direct visualization of the tear are other ways to diagnose lunotriquetral ligament tears.
One study of 85 patients with distal radius fractures treated surgically found that 53% of the patients also had a TFCC lesion diagnosed by arthroscopy. However, they found no correlation between TFCC lesion and any specific parameter on x-ray. Therefore, the initial radiograph of a distal radius fracture isn’t predictive of TFCC injury.[10]
Treatment / Management
Initial treatment includes rest, physiotherapy , and corticosteroid injections. The length of your time to aim conservative treatment before advancing to surgical options varies. Six months of conservative treatment is cheap if there’s not DRUJ instability.
There is limited evidence to support the utilization of bracing as a treatment option for TFCC tears. One case report followed one patient with a TFCC tear for one year. This patient wore a replacement brace for 12 weeks after failing conservative management as an alternate to surgery. The results were a rise in upper extremity use immediately following wearing the brace and protracted improvements noticed at a follow-up appointment in one year. This was the primary study to point out a beneficial non-surgical option after failing conservative management.[11] Further information is important regarding the utility of bracing for TFCC.
Surgical options should be a consideration if conservative treatment fails or if there’s DRUJ instability. Common surgical options include arthroscopic repair, arthroscopic debridement, ulnar shortening, and therefore the Wafer procedure.
A debridement may be a surgical option that induces bleeding to stimulate healing. Debridement has beneficial outcomes for central TFCC tears but has been shown to possess worse outcomes in degenerative tears or patients with higher positive ulnar variance.[12] Regarding the arthroscopic vs. open approach, there’s no significant difference in pain, reoperation rate, grip strength, or range of motion between the 2 approaches.[13]
Surgical treatment will depend upon the Palmer classification of the injury, discussed within the staging section.
1A: This injury is in an avascular region which will not heal if it doesn’t receive treatment. thanks to the shortage of vascularity, it doesn’t answer direct surgical management, so debridement is the intervention of choice.[3]
1B: the world has vascularization, so an immediate surgical repair is an option. If the triangular fibrocartilage disc is totally detached from the ulnar insertion, then there’s an injury to the radioulnar ligaments, and there’ll be instability. If this is often the case, the quantity of retraction of the tendon should be measured, and a tendon graft could also be necessary as a part of the surgical repair. Partial tears wouldn’t involve radioulnar ligament injury and thus are stable and will be treated with sutures arthroscopically. Tears at the foveal insertion require bony reattachment, and thus these are of more significant consequence than styloid insertion tears.[3]
1C: Arthroscopy and debridement are both options. A debridement is an option if the ligaments are beyond repair.[3]
1D: If the injury involves radioulnar ligament damage, surgical reattachment is the treatment of choice. If the injury spares the radioulnar ligaments, partial resection via arthroscopy is an option.[3]
Type 2 lesion treatment is separated by whether the lunotriquetral ligament is torn or intact. the simplest thanks to determining this is often MR arthrography, although CT arthrography is additionally effective. Types 2A, 2B, and 2C lesions can have conservative therapy. If conservative management fails, an inexpensive next step is the Wafer procedure, which is the resection of the distal aspect of the ulnar head. Type 2E lesions also can be treated by resection of the ulnar head. Type 2D lesions are often treated via ulnar shaft-shortening with osteotomy.[3]
For patients with chronic tears who undergo surgery, one study of 57 patients who had pain for nine months on average before surgery found a 98% satisfaction and return to figure around nine weeks.[14]
Contraindications to arthroscopy include if the wrist is an arthritic or insufficient ligament on the scaphoid and lunate.[14]
Treating athletes can vary from treatment for non-athletes. A high school athlete who won’t compete beyond high school should begin with four weeks of rest, ice, and anti-inflammatories. For elite athletes, if there’s no distal radioulnar joint instability, one week of rest with splinting and re-examination after one week is cheap. If there’s a tear of the TFCC with the instability of the distal radioulnar joint, this is often potentially career-threatening. If non-surgical treatment is elected, this might include long arm immobilization for 3 weeks followed by short-arm immobilization for 3 weeks with a gradual return to play. If there’s a chronic tear, the athlete can receive counsel that the danger of further damage is minimal. Therefore, the athlete can prefer to attempt to play through the injury until the season is over, or the athlete could elect surgery immediately.[7] Corticosteroid injections also are an option, especially in elite athletes who elect to delay surgical intervention in an effort to end the season.
Differential Diagnosis
Hypothenar hammer syndrome: Differentiate because there could also be discoloration, fingertip ulcers, or splinter hemorrhages on the fourth or fifth digits. An angiogram could also be ready to diagnose this condition.
Ulnar carpal impingement: Differentiate because this is often commonly a result of ulnar shortening thanks to surgical resection from a previous injury.
Ulnar extensor or flexor tendonitis: Movements that cause the muscle to fireside will provoke the pain. Pain may radiate along the muscle belly counting on the degree of inflammation.
DRUJ chondral lesions or osteoarthritis: Differentiate via radiographic evidence implicational a chondral lesion or osteoarthritis.
