Triangular Fibrocartilage Complex Injuries

As the name suggest, the TFCC is triangular in shape. Palmer found an inverse relation between ulnar variance and TFCC thickness of the TFCC: The TFCC is thicker in individuals who are ulnar minus.[5] Generally, the TFCC is 1-2 mm thick at its center. This may thicken to 5 mm where the TFCC inserts into the eccentric concavity of the ulnar head and projecting styloid.

The TFCC extends ulnarly to insert into the base of the ulnar styloid (see the first image below). Distally, it inserts into the lunate via the ulnolunate (UL) ligament and into the triquetrum via the ulnotriquetral (UT) ligament (see the second and third images below), the hamate, and the base of the fifth metacarpal. Radially, the TFCC arises from the ulnar margin of the lunate fossa of the radius (see the fourth image below).

Underneath the TFCC is the ulnar head. The seat, or the convex portion of the ulnar head, articulates with the sigmoid notch of the radius (see the image below). The cartilage-covered nonarticular pole of the ulnar head is deep to the articular disk.

The ulnocarpal portion of the TFCC is composed of the discus articularis and the UL and UT ligaments (referred to by some as the disk carpal ligaments). Embryologic studies have demonstrated that these ligaments arise from the disk and are critical to the carpal suspensory function of the TFCC.

The dorsal and palmar branches of the anterior interosseous artery and dorsal and palmar radiocarpal branches from the ulnar artery supply blood to the periphery of the TFCC. These vessels supply the TFCC in a radial fashion, with histologic sections demonstrating that the vessels penetrate the peripheral 10-40% of the disk. The central portion and radial attachment are avascular.

Mikic demonstrated that the percentage of the peripheral disk that is vascularized is reduced from one third in a young patient to one fourth in patients of advanced age.[6]

Because the periphery of the TFCC has a good blood supply, tears in this region can be repaired. By contrast, tears in the central avascular area must be debrided because they have no potential for healing.

The richly vascularized dorsal radioulnar (DRU) ligament and palmar radioulnar (PRU) ligament are composed of thick, longitudinally oriented collagen fiber bundles that blend in with the central avascular fibrocartilaginous portion.

When the TFCC is viewed during wrist arthroscopy, the styloid attachment appears folded. Some of the blood vessels to the TFCC enter between these folds. This fold, combined with the vascular hilum, is termed the ligamentum subcruentum, which actually is the confluence of the TFCC and the V-shaped ligament (disk ligament) as it extends from the hilar area of the styloid to its twin insertions on the lunate and triquetrum.

From a distal perspective, the TFCC has two distinct insertions into the ulna—a superficial portion and a deep portion. The superficial components, the DRU and PRU ligaments, insert into the base of the styloid. The deep portion, the ligamentum subcruentum, inserts into the fovea near the axis of forearm rotation.

Controversy exists concerning the biomechanical changes of the TFCC during pronation and supination. A number of authors claim that the DRU ligament tightens during pronation and relaxes with supination; other authors claim the exact opposite.

Nakamura et al may have solved this question by using a custom-made surface coil allowing complete freedom of wrist motion. From magnetic resonance imaging (MRI) of the wrist in coronal and sagittal planes at maximal pronation and neutral and maximal supination, they showed that during pronation and supination, the TFCC twists at its origin.[7]  This should result in friction between the proximal side of the disk proper and the ulnar head during rotation. The friction may increase in ulnocarpal abutment syndrome because of ulnar variance, potentially explaining the degeneration seen in Palmer class 2 TFCC tears (see Pathophysiology).

Palmer and Werner looked at the axial load distribution through the distal radius and ulna[8] and demonstrated that with normal axial loading, 20% of the force is transmitted through the ulna and 80% through the radius. Their data also illustrated that small changes in relative ulnar length can significantly alter load patterns across the wrist. For example, with a distal radius fracture that settles 2.5 mm, an increase in ulnar axial load of approximately 40% can be expected.

Palmer, Werner, Glisson, and Murphy demonstrated that the percentage of axial force transmitted through the ulna decreases by sequential removal of the horizontal portion of the TFCC.[5] This percentage decrease is accentuated with more positive ulnar variance.

In a cadaver study, Adams demonstrated that no significant kinematic or structural changes resulted from an excision that did not violate the peripheral 2 mm of the disk and that constituted less than two thirds of the disk area.[9]

TFCC tears are associated with a positive ulnar variance. Ulnar variance increases with pronation and grip and decreases with supination.

The floor of the extensor carpi ulnaris (ECU) tendon sheath broadly connects with the TFCC. After release of the TFCC from its distal ulna attachment, Tang demonstrated a 30% increase in ECU tendon excursion during wrist extension.[10] This suggests the following:

• The TFCC is an important pulley for the ECU tendon
• Disruption of the normal ECU excursion may contribute to abnormal loading and force transmission through the ulnar wrist and TFCC

Palmer classification of TFCC abnormalities

The Palmer classification divides TFCC abnormalities into two main classes, which are then further divided into several subtypes.

Palmer class 1 (traumatic) TFCC abnormalities are divided into the following subtypes:

• A - Central perforation (see the first, second, and third images below)
• B - Ulnar avulsion (see the fourth, fifth, and sixth images below) with or without distal ulnar fracture
• C - Distal avulsion
• D - Radial avulsion with or without sigmoid notch fracture

Palmer class 2 (degenerative [ulnocarpal abutment syndrome] stage) TFCC abnormalities are divided into the following subtypes:

• A - TFCC wear
• B - TFCC wear with lunate and/or ulnar chondromalacia
• C - TFCC perforation with lunate and/or ulnar chondromalacia
• D - TFCC perforation with lunate and/or ulnar chondromalacia and lunotriquetral (LT) ligament perforation
• E - TFCC perforation with lunate and/or ulnar chondromalacia, LT ligament perforation, and ulnocarpal arthritis

In a small series, Nance et al described eight patients who were presumed to have solitary TFCC tears but were found on wrist arthroscopy to have a combination of 1A and 1B injuries.[11]  They suggested that this combined pattern, which is not currently categorized in the Palmer classification system and is not reliably diagnosed preoperatively, might usefully be considered a new subtype in this system.

In 2022, Schmitt et al proposed a new CUP (central, ulnar, peripheral) classification for TFCC injuries, arguing that current classifications have significant drawbacks.[12]

Causative conditions for TFCC injuries include the following:

• Falls onto pronated hyperextended wrist
• Power-drill injuries in which the drill binds and rotates the wrist instead of the bit
• Distraction force applied to the volar forearm or wrist
• Distal radius fractures

Mikic looked at 180 wrist joints in 100 cadavers, ranging in age from fetuses to 94 years.[6] He demonstrated that degeneration of the TFCC begins in the third decade of life and progressively increases in frequency and severity in subsequent decades. After the fifth decade of life, he noted no normal-appearing TFCCs. Viegas and Ballantyne found similar results.[13]

McNamara et al performed a systematic review and meta-analysis of 43 studies that addressed the outcomes of different treatment approaches for symptomatic Palmer type 1 TFCC injuries.[14]  Patients who underwent debridement for any Palmer type 1 injury returned to work at a rate of 92%, but only 44% were free of pain. Of patients with 1B lesions that were repaired, 68.3% were able to return to work, and 41% had persistent pain. The 1D lesions were treated with both repair and debridement, and results were similar. Data for types 1A and 1C were limited. Patients with 1A lesions treated with debridement still had high rates of being unable to return to work.

Arthroscopic repair

A review by de Araujo et al of 17 patients (average age, 33 y) after arthroscopic repair of Palmer class 1B tears showed that at 8 months' follow-up, 16 patients (48%) were satisfied or very satisfied; one patient was not satisfied.[15] At 16-24 months' follow-up, 70% of the patients were satisfied.

Reiter et al performed a retrospective study of 46 patients who underwent arthroscopic repair of Palmer class IB tears to determine patients' functional and subjective outcomes, as well as whether clinical outcomes were related to ulnar length.[16] Good-to-excellent results were achieved in 63% of the patients, including increased range of motion (ROM) and grip strength and pain relief. Neutral or positive ulnar variance was not a contraindication for repair and did not necessitate simultaneous ulnar shortening.

Sagerman and Short reviewed 12 patients after arthroscopic repair of Palmer class 1D tears (average follow-up, 17 mo) and found good or excellent results in 67% of patients.[17]

Trumble et al reviewed 24 patients (average age, 31 y) after arthroscopic repair of Palmer classes 1B, 1C, and 1D tears.[18] Treatment occurred within 4 months after injury, with a follow-up of 34 months. Postoperative ROM was 89%, and grip strength was 85%. Thirteen of 19 patients returned to their original jobs or sports. Follow-up studies demonstrated that the TFCC was intact in 12 of 15 patients.

Corso et al reviewed 44 patients (average age, 32.5 y) and 45 wrists with zone-specific repair and follow-up of 37 months and found excellent results in 29 patients, good results in 12, fair results in one, and poor results in three.[19]

In a study of 16 competitive athletes with wrist TFCC, McAdams et al found that arthroscopic debridement or repair of TFCC injury provided pain relief and allowed patients to return to play, with slower recovery in patients with concomitant ulnar-side wrist injuries.[9] .

Yao et al compared an all-arthroscopic TFCC repair technique with an outside-in technique in 10 matched pairs of fresh-frozen cadaveric wrists and found that the all-arthroscopic technique resulted in decreases in operating time, postoperative immobilizations, and irritation from suture knots below the skin.[20, 21]

In a study of 75 patients who underwent TFCC repair by arthroscopic (n = 36) or open technique (n = 39), Anderson et al found that there was no statistical difference in clinical outcome for the two approaches to TFCC repair.[22] They did note an increased rate of postoperative superficial ulnar pain in patients who underwent open repair (14/39) as compared with those who underwent arthroscopic repair (8/36). Females had a higher rate of reoperation.

In a cadaveric study comparing the biomechanical strength of knotless suture anchor repair and the traditional outside-in repair of peripheral TFCC tears, Desai et al concluded that the all-arthroscopic suture anchor TFCC repair was biomechanically stronger than the outside-in repair and that the former allowed repair of both superficial and deep layers of the articular disk directly to bone, thereby restoring native TFCC anatomy.[23]  They suggested that the absence of knots might prevent irritation to the surrounding soft tissues.

Arthroscopic debridement

Minami et al reviewed 16 patients (average age, 30 y) with a follow-up of 35 months. Palmer class 1 tears were found in 11 patients, and Palmer class 2 tears were found in five.[24] Of the 16 patients, 13 returned to their previous jobs. Positive ulnar variance and LT tears were associated with a poor outcome; Palmer class 1 tears were associated with excellent results; and Palmer class 2 tears were associated with poor results.

Westkaemper et al reviewed 28 patients (average age, 30 y) with a follow-up of 15.4 months. Excellent results were found in 13 patients, with good results in eight, fair results in two, and poor results in five.[25]

De Smet et al conducted a retrospective survey of 46 patients who underwent debridement with or without wafer distal ulna resection.[26]  Patients were sent a questionnaire on pain, disability, and time off from work. Mean scores on the Disabilities of the Arm, Shoulder, and Hand (DASH) scale decreased from 42 to 28. The pain was considered severe in 12 patients; 32 patients were satisfied. There were significant differences in the outcome between use of debridement only and use of debridement with wafer resection of the distal ulna.

Ulnar shortening

Minami and Kato reviewed 25 patients (average age, 32 y) with follow-up of 35 months.[27] Ulnar variance averaged more than 3.5 mm. Ulnar-shortening osteotomies of 3 mm, fixed with a 6-hole 3.5-mm dynamic compression plate (DCP), were performed. Twenty-three patients also had arthroscopy. Palmer class 1 tears were found in 15 patients; only the flap was removed. Palmer class 2 tears were found in eight; no debridement was performed.

Complete relief or only occasional mild pain was found in 23 patients.[27] Of the 25 patients, 23 returned to their original work. Osteotomies healed at an average of 7 weeks. This research suggests that ulnar shortening is indicated in both traumatic and degenerative tears associated with ulnar positive variance.

Trumble et al reviewed 21 patients with treatment delays longer than 6 months and follow-up of 29 months.[28] Palmer class 1 tears were repaired. Ulnar-shortening osteotomies of 2-3 mm fixed with 6-hole 3.5-mm DCPs were performed. Complete pain relief was found in 19 of 21 patients. Grip strength was 83%; ROM was 81% of normal. Treatment delays longer than 6 months from the time of injury resulted in a higher recurrence of symptoms; in these situations, the authors recommended combining arthroscopic repair with ulnar shortening.

Hulsizer et al reviewed 97 patients (average age, 34 y; average ulnar variance, 0.4 mm) with central or nondetached ulnar peripheral tears initially treated with debridement.[29] Persistent pain more than 3 months after surgery was reported by 13 patients. A 2-mm ulnar-shortening osteotomy, fixed with a 6-hole 3.5-mm DCP, was performed on these 13 patients. Complete pain relief at 2.3-year follow-up was reported by 12 patients. An ulnar-shortening osteotomy of 2 mm was recommended for patients in whom arthroscopic debridement failed.

In a retrospective study (N = 256), Yamanaka et al compared preoperative and postoperative TFCC thickness and TFCC angle, using MRI to quantitatively evaluate the effect of ulnar-shortening osteotomy on disk regeneration and the suspension effect on the TFCC.[30]  They found that ulnar-shortening osteotomy yielded a high residual potential for regeneration in the disk proper. There was no correlation between disk regeneration or the suspension effect on the TFCC and the Mayo wrist score.

Seo et al assessed the results of arthroscopic peripheral repair (n = 15) against those of arthroscopic debridement (n = 16) for treatment of chronic unstable TFCC tears in 31 ulnar-positive patients undergoing ulnar-shortening osteotomy (minimum follow-up, 24 mo).[31] Improvements were noted in both groups; however, grip strength, DASH, and Patient-Rated Wrist Evaluation (PRWE) scores were better in the repair group than in the debridement group. Recovery from DRUJ instability noted during preoperative evaluation was superior in the repair group as well.

The history of triangular fibrocartilage complex (TFCC) injuries includes ulnar-side wrist pain (frequently accompanied by clicking), a fall or trauma, and/or mechanical symptoms that improve with rest and worsen with activity.

In the physical examination, it is important to look for the following:

• Painful grinding or clicking with wrist range of motion (ROM)
• Weakness
• Ulnar deviation of the wrist with the forearm in neutral produces ulnar wrist pain and occasional clicking (perform a TFCC compression test)
• Instability of the distal radioulnar joint (DRUJ) joint with shucking the distal radius and ulna between the examiner's fingers (perform a DRUJ stress test; always compare this with the opposite wrist)
• Piano key sign, which is a prominent and ballottable distal ulna with full pronation of the forearm
• Ulnar carpal sag
• Lunotriquetral (LT) interval tenderness
• Positive LT ballottement or shuck test
• Extensor carpi ulnaris (ECU) tendon subluxation

Plain radiography

Obtain neutral forearm rotation posteroanterior (PA) and lateral x-rays of the wrist to allow assessment of ulnar variance and to assess for chondromalacia of the lunate or ulnar head, degenerative joint disease of the distal radioulnar joint (DRUJ), lunotriquetral (LT) or scapholunate (SL) instability, dorsiflexed intercalated segment instability (DISI), or volarflexed intercalated segment instability (VISI).

Wrist arthrography

The accuracy and diagnostic capability of triple-injection wrist arthrograms have been challenged over the past decade. The test is not specific, with a high incidence of findings on the contralateral asymptomatic side. Wrist arthrography has poor diagnostic agreement with chronic wrist pain.

Positive wrist arthrograms are obtained in 27% of asymptomatic adults. Palmer class 1B tears have positive arthrograms with a DRUJ injection but not with a radiocarpal injection. Palmer class 1C tears have variable findings. Palmer class 1D tears usually have positive arthrograms.

Magnetic resonance imaging

Magnetic resonance imaging (MRI) can predict triangular fibrocartilage complex (TFCC) lesions with 0.8 sensitivity and 0.7 specificity using a dedicated wrist coil.[32, 33, 34] Fat-suppression MRI scans best exhibit the complex structure of the TFCC.

A prospective study by Lee et al suggested that the addition of axial traction during wrist magnetic resonance arthrography may significantly improve the ability of this modality to detect and visualize tears of the TFCC.[35]  

A study by Thomsen et al found postcontrast 3T indirect magnetic resonance arthrography to have better diagnostic performance than precontrast imaging for the overall detection of class 1B TFCC tears.[36]  

A study by Zhan et al suggested that the more detailed injury patterns detectable with high-resolution 3T MRI may indicate the need for refinement of the classic Palmer classification of TFCC injuries.[37]

Ultrasonography

Ultrasonography (US) has not been as widely employed for imaging TFCC lesions as the preceding modalities have. However, high-resolution US may be useful for diagnosing these injuries.[38]  A study by Yuine et al found that using force-monitor US to assess DRUJ instability may help identify TFCC-injured wrists.[39]

Wrist arthroscopy has been the criterion standard for diagnosis of these injuries; it can be a diagnostic tool or a therapeutic tool. When compared with other imaging studies, wrist arthroscopy has typically been found to be more accurate. It also allows assessment of the size of the tear, determination of whether an unstable flap is present, and detection of associated synovitis and chondral and ligamentous lesions. However, one study suggested, on the basis of relatively low interrater correlation, that the status of arthroscopy as the reference standard should be reconsidered.[40]  

With the trampoline test, normally a probe should bounce off of the TFCC. If a probe sinks into the TFCC as if it is on a feather bed, a tear is usually present.

Wrist arthroscopy is used in the diagnosis of TFCC tears associated with distal radius fractures. Richards examined 118 fractures[41] ; these fractures had wrist arthroscopy that required reduction and fixation because of a failure to obtain or maintain a reduction.

Lee Master et al undertook a study to determine the accuracy of the wrist insufflation test on the basis of mean radiocarpal and midcarpal joint space volumes in 29 patients who underwent three- or four-portal radiocarpal and radial midcarpal portal insufflation before wrist arthroscopy.[42]  They concluded that the test allowed detection of complete SL interosseous ligament and TFCC tears and complete SL interosseous ligament and LT interosseous ligament tears.

If a congruent reduction cannot be achieved or if the dorsal instability is unstable in 30° of supination, then arthroscopic evaluation of the triangular fibrocartilage complex (TFCC) is recommended with repair as needed.

Repairing TFCC tears is contraindicated in the presence of infection or degeneration. Palmer class 2 degenerative TFCC tears (see Pathophysiology) represent a pathologic progression of disease associated with ulnar impaction syndrome.

Degeneration of the TFCC is found with repetitive pronation and axial grip loading in association with positive ulnar variance and impaction between the ulnar head and the proximal pole of the lunate. Treatment of degenerative TFCC tears associated with ulnar impaction syndrome consists of nonoperative treatment first with immobilization, avoidance of aggravating activities, and nonsteroidal anti-inflammatory drugs (NSAIDs).

Palmer class 2A and 2B lesions that fail to respond to conservative treatment are treated with gentle debridement. If the patient is ulnar-positive and symptomatic, a formal ulnar shortening is considered. An arthroscopic wafer is contraindicated, in that this would require resection of intact TFCC to perform the procedure or require performing the procedure entirely through the distal radioulnar joint (DRUJ) portals.

The surgical indications for an arthroscopic wafer procedure are a Palmer class 2C or 2D lesion in a positive ulnar variance of not more than 2 mm without evidence of lunotriquetral (LT) instability. If LT instability is present, this is addressed with formal ulnar shortening in an attempt to tighten the ulnocarpal ligaments and decrease the motion between the lunate and triquetrum.

For patients with a positive ulnar variance of more than 2 mm, formal ulnar shortening is performed. For patients with neutral or negative ulnar variance and a Palmer class 2C lesion, arthroscopic debridement is performed. Palmer class 2E lesions respond unpredictably to arthroscopic debridement. They are usually treated with a salvage procedure such as a limited ulnar head resection, a Sauve-Kapandji procedure, or a Darrach procedure that addresses the DRUJ and LT joint pathology.

Initial treatment of both symptomatic degenerative and traumatic TFCC tears is 8-12 weeks of conservative therapy consisting of the following:

• NSAIDs
• Immobilization in slight flexion and ulnar deviation in a short arm cast for 4-6 weeks, followed by removable wrist splints and physical therapy
• Initial treatment with long arm casting for 4-6 weeks for traumatic tears and 3-4 weeks of short arm casting for degenerative tears recommended by some

The natural history of symptomatic tears, according to Osterman's study of 133 patients,[43] is as follows:

• Traumatic tears with neutral ulnar variance did not worsen over time, and one third of patients were asymptomatic at 9.5 years of follow-up
• In persons with traumatic tears with positive ulnar variance, two thirds of patients worsened over time both symptomatically and radiologically

Over a 3-year period, Lee et al treated 117 patients with TFCC tears who did not have DRUJ instability.[44]  They found nonsurgical treatment to be moderately successful in treating these patients and recommended a minimum of 6 months of nonsurgical treatment as the first-line treatment for this injury.

A study by Sander et al compared the outcomes of symptomatic TFCC lesions with a stable DRUJ after conservative treatment and arthroscopic debridement and found the two approaches to yield similar results.[45] In view of their finding that conservative treatment was a sufficient and reliable option, the authors proposed it as first-line treatment for TFCC lesions with a stable DRUJ.

Acute isolated TFCC disruption with dislocation or instability of DRUJ

Isolated TFCC disruptions may be associated with DRUJ instability. These injuries are often associated with distal radius and forearm fractures. Forced hyperpronation usually results in dorsal dislocation.

On physical examination, the ulnar head is prominent dorsally and the patient has limited forearm supination. Less commonly, volar dislocation results from forced supination. Dorsal skin dimpling is often observed, and pronation is limited. The volarly displaced ulnar head is often not felt because of the overlying soft tissues.

When dislocation of the ulnar head is not present, subluxation and instability are more difficult to diagnose. Subluxation and instability of the DRUJ are assessed on physical examination by shucking the radius and ulna past each other to determine the amount of dorsal/palmar laxity. This should be performed in neutral, pronation, and supination and compared to the opposite side.

The more common dorsal DRUJ instability is reduced with the forearm in supination. Palmar DRUJ instability is reduced with the forearm in pronation. If a congruent reduction can be achieved and the forearm is stable through a full range of motion (ROM), then the forearm is immobilized in a long arm cast in the position of stability for 4-6 weeks.

With a dorsal dislocation, the preferred position of immobilization is in approximately 30° of supination for 4 weeks, followed by gradual reduction to neutral over the next 2 weeks. If a congruent reduction cannot be achieved or if the dorsal instability is unstable in 30° of supination, then arthroscopic evaluation of the TFCC is recommended with repair as needed.

If the DRUJ joint remains unstable, open reduction is required to remove interposed structures. When instability persists with forearm ROM, supplemental Kirschner wire (K-wire) stabilization just proximal to the DRUJ is recommended for 4-6 weeks.

Instability of the DRUJ is often associated with distal radius fractures and Galeazzi fracture-dislocations. Anatomic reduction of these fractures often stabilizes the joint. When fixation of these fractures does not stabilize the joint, stabilization can be obtained with either (1) long arm casting in a reduced position, open reduction, and TFCC repair or (2) supplemental K-wire fixation.

Rettig and Raskin noted a high association with Galeazzi fractures within 7.5 cm of the midarticular surface of the distal radius and with DRUJ instability after open reduction and internal fixation (ORIF) of the radial shaft fracture.[46]

In individuals with radial head fracture and tenderness over the DRUJ, every attempt should be made to preserve the radial head to prevent proximal migration of the radius. DRUJ disruption associated with a displaced radial head fracture and proximal migration of the radius is termed the Essex-Lopresti fracture. Geel and Palmer noted good results in 18 of 19 patients with radial head fracture and pain at the DRUJ who were treated with ORIF of the radial head.[47]

Arthroscopic vs open repair

In a study of 16 competitive athletes with wrist TFCC injuries from 2001 through 2005, McAdams et al found that arthroscopic debridement or repair of TFCC injury provided pain relief and allowed patients to return to play. There was slower recovery in patients with concomitant ulnar-side wrist injuries.[48]

Yao et al compared an all-arthroscopic TFCC repair technique with an outside-in technique in 10 matched pairs of fresh-frozen cadaveric wrists and found that the all-arthroscopic technique resulted in decreased operating time, reduced postoperative immobilizations, and decreased irritation from suture knots below the skin.[49, 50]

In a study of 75 patients who underwent TFCC repair by arthroscopic (n = 36) or open technique (n = 39), Anderson et al found that there was no statistical difference in clinical outcome between the two approaches to repair.[51] They did note an increased rate of postoperative superficial ulnar pain in patients who underwent open repair (14/39 with open technique vs 8/36 with arthroscopy). Females had a higher rate of reoperation.

Reiter et al performed a retrospective study of 46 patients who underwent arthroscopic repair of Palmer class 1B tears to assess functional and subjective outcomes, as well as to determine whether clinical outcomes were related to ulnar length.[16] Good-to-excellent results were achieved in 63% of the patients, including increased ROM and grip strength and pain relief. Neutral or positive ulnar variance was not a contraindication for repair and did not necessitate simultaneous ulnar shortening.

A systematic review by Andersson et al examined the outcomes of open and arthroscopic repair of TFCC injuries.[52] The primary outcome measure was the rate of postoperative DRUJ reinstability; secondary outcome measures were ROM, grip strength, residual pain, functional wrist scores, complication rate, and reoperation rate. The two repair approaches yielded comparable results in terms of DRUJ reinstability and functional outcome scores. The evidence was insufficient to allow recommendation of one technique over the other in clinical practice.

A study by Yeh et al (N = 201; mean age, 26.7 y; mean follow-up, 32.6 mo) evaluated the functional outcomes of patients who underwent arthroscopic repair of foveal TFCC tears with suture anchors and adjuvant platelet-rich plasma (PRP) injections after the surgical procedure.[53] Mean modified Mayo wrist score improved (from 48.5 ± 2.6 to 82.4 ± 2.5), and mean Disabilities of the Arm, Shoulder, and Hand (DASH) score decreased (from 39.2 ± 6.7 to 10.6 ± 7.5). Overall, 92.5% of the patients achieved satisfactory wrist function according to the modified Mayo wrist score, and patients with satisfactory scores returned to sports or work activities, retaining normal range of motion (ROM).

Open repair

Make a dorsal ulnar incision between the fourth and fifth extensor compartments. Carry the dissection down to the dorsal radioulnar (DRU) ligament. Reflect the DRU ligament and the periosteum over the lunate fossa. Place horizontal mattress sutures in the TFCC through drill holes placed in the dorsoulnar aspect of the distal radius.

Wrist arthroscopy

Indications for wrist arthroscopy include acute unstable tears, acute tears that fail to respond to conservative management, and chronic tears for which conservative management fails.[48, 54, 55, 56]

General arthroscopic principles are as follows:

• Debride to a stable smooth rim of tissue
• Maintain a 2-mm peripheral rim
• Excise less than two thirds of the central portion of the TFCC
• Maintain the integrity of the DRU ligament, the palmar radioulnar (PRU) ligament, and the disk carpal ligaments

Traumatic central tears (Palmer class 1A)

Perform debridement as above.

Traumatic ulnar-side tears (Palmer class 1B) with outside-in technique

Debride the synovitis and the edges of the tear.[57] Make a 1-cm incision just radial to the extensor carpi ulnaris (ECU) tendon. Open the radial aspect of the ECU tendon sheath for 1 cm. Retract the ECU palmarly.

Under arthroscopic visualization, pass two needles through the capsule and across the tear using a meniscus mender or similar TFCC repair device. Use a wire loop passed through one needle to retrieve a 2-0 polydioxanone suture passed through the other needle. This creates a loop. Tie the suture over the dorsal wrist capsule, approximating the tear; two to four sutures may be required.

Reconstruct the ECU tendon as needed. Immobilize the wrist and elbow for 4 weeks in a splint or Muenster cast.

Ulnar extrinsic ligament tears (Palmer class 1C)

Perform a miniopen or arthroscopic repair using zone-specific cannulas. Stay between the ECU and the flexor carpi ulnaris (FCU) to avoid the neurovascular bundle.

Traumatic radial-side tears (Palmer class 1D)

Debride as with a Palmer class 1A tear, or repair as follows:

• Debride the edge of the sigmoid notch with a shaver down to bleeding bone
• Make drill holes through the distal radius with a K-wire passed percutaneously into the joint from the sigmoid notch across the distal radius
• Pass a 2-0 double-ended polydioxanone suture on long needles through the TFCC and into the drill holes
• Tie the suture on the surface of the radius through a small incision while protecting the superficial radial nerve
• Pin the DRUJ in neutral rotation with a single 0.062-in. K-wire
• Immobilize the wrist and elbow for 8 weeks in a splint or Muenster cast
• Transosseous suture anchors can be used in place of drill holes

Degenerative tears (Palmer classes 2A and 2B)

Gently debride. If the patient is ulnar-positive and symptomatic, use open ulnar shortening.

Degenerative tears (Palmer class 2C)

Gently debride in patients who are ulnar-neutral or ulnar-negative. For patients who are ulnar-positive, consider the arthroscopic wafer procedure.

Wnorowski demonstrated almost a 50% unloading of the ulnar side of the wrist after excision of the central portion of the TFCC and resection of the radial two thirds of the width of the ulnar head to a depth of subchondral bone.[58] Patients with an arthroscopic wafer procedure may have a more prolonged postoperative course than those with open ulnar shortening.

Degenerative tears (Palmer class 2D)

Treatment is similar to that for Palmer class 2C tears. Carefully assess LT instability. If the LT joint is stable, perform debridement. If it is unstable, consider an open shortening osteotomy to unload the ulnar head and tighten the ulnar extrinsic ligaments. Then, consider an LT fusion or pinning or an LT ligament repair.[59] An arthroscopic wafer procedure is contraindicated, because it leads to more laxity in the ulnar extrinsic and LT ligaments.

Degenerative tears (Palmer class 2E)

Degenerative tears have an unpredictable response to arthroscopic debridement. These tears usually require a salvage operation. The DRUJ and the LT joint must be addressed. A limited ulnar head excision can be performed. The Sauve-Kapandji procedure involves radioulnar joint arthrodesis and proximal ulnar pseudarthrosis. The Darrach procedure is a resection of the distal end of the ulna.

Ulnar-shortening osteotomy

Consider ulnar-shortening osteotomy for patients with positive ulnar variance, patients in whom debridement fails, and patients who present with a delay in treatment of longer than 6 months.

Advantages of an ulnar-shortening osteotomy are as follows:

• It is extra-articular
• It maintains the mechanical integrity of the DRUJ
• It maintains the origins and insertions of the ligamentous tissue and capsule forming the peripheral aspect of the TFCC; it may result in tightening of the ulnocarpal complex, including the LT ligament, with shortening
• It is potentially less painful than an arthroscopic resection

After surgery, all patients are immobilized immediately. If debridement alone is performed, patients are placed in a bulky dressing and started on motion exercises at 5-7 days. All other patients are placed in a sugar-tong splint. Skin sutures are removed at 7-10 days. A Muenster-style cast is used for 2 weeks, followed by a short arm cast for 3 weeks for patients who have undergone TFCC repairs.

Complications include the following:

• Infection
• Stiffness
• Repair failure
• Wrist arthroscopy complications
• Continued pain
• Decreased strength
• Hardware failure
• Nonunion (in cases of nonunion, perform an ulnar-shortening osteotomy)