Editorial Commentary: Arthroscopic Capsular Repair of Wrist Triangular Fibrocartilage Complex Tears: Beware That Apparent Isolated Atzei Class 1 (Isolated Distal Component) Tears May Include a Proximal Component

Accumulating knowledge about the anatomy of the triangular fibrocartilage complex (TFCC) and its function has revealed that the foveal insertion of the TFCC plays a key role in distal radioulnar joint stability rather than the superficial fibers that insert into the ulnar styloid. Recently, the interest in torn peripheral TFCC repair has been shifting from capsular repair for Atzei class 1 to foveal repair for Atzei class 2 or 3. Most acute Atzei class 1 tears spontaneously heal without surgical repair; in contrast, in cases of sustained pain and distal radioulnar joint instability even after successful Atzei class 1 repair, the unrecognized proximal component TFCC tear concomitant with a distal component TFCC tear may exist and appropriate treatment for the proximal component TFCC tear should be combined. Although overall successful results have been reported using various repair techniques, the most important consideration is re-establishing biologic regeneration potential at the insertion site of torn TFCC.     

Ulnar styloid fixation in the treatment of posttraumatic instability of the radioulnar joint: a biomechanical study with clinical correlation

Biomechanical displacement testing was done on nine fresh human upper extremities to define the stabilizing influence of the triangular fibrocartilage on the radioulnar joint and the efficacy of triangular fibrocartilage-ulnar styloid avulsion fracture repair in restoring lost stability. Test data confirmed that the triangular fibrocartilage is a major stabilizer of the radioulnar joint and internal fixation of triangular fibrocartilage-ulnar styloid avulsion fractures can restore preavulsion stability in all positions of forearm rotation. On the basis of this data and a successful clinical experience, primary repair of displaced ulnar styloid avulsion fractures is advised as a means of stabilizing the radioulnar joint and preventing the disability associated with chronic radioulnar joint instability.     

Die dorsale Kapseldoppelung zur Therapie der dorsalen Instabilität des distalen Radioulnargelenks

Objective

To stabilize the distal radioulnar joint (DRUJ) by performing dorsal capsular imbrication in patients presenting with dorsal instability. The goal was to reduce pain and prevent the occurrence of posttraumatic arthrosis.

Indications

Posttraumatic dorsal instability of the DRUJ with missing block while performing translational activities in the DRUJ or subluxation while actively rotating the forearm. Cases, in which other stabilizing techniques, such as, sutures of the triangular fibrocartilage complex failed.

Contraindications

DRUJ arthrosis, previous surgical interventions to the capsule area of the DRUJ, instabilities due to osseous reasons (malposition or pseudarthrosis) should already have been treated.

Surgical technique

Dorsal approach and opening of the 5th extensor compartment to expose the dorsal joint capsule. A longitudinal division of the capsule was performed and sufficient tissue on the radial and ulnar border was retained to ensure a solid suture technique. Then 2 U-shaped sutures using FiberWire suture material were made. Correction of the malposition and repositioning the forearm into supination. Tightening of the prepared capsule sutures and closing of the retinaculum with a resorbable suture.

Postoperative management

Patients wore a long-arm cast with the forearm being in supination for a period of 4 weeks. Following cast removal, patients wore a forearm splint for a period of 4 weeks to limit forearm pronation/supination at 45°. Full load on the wrist was allowed after 12 weeks.

Results

The subjective and functional outcomes of 20 patients having received capsular imbrication using this technique were good and entailed no significant complications. The postoperative DASH was 15.8 points. Of the 20 patients, 17 patients (85?%) had a reduction of pain. Symptoms of DRUJ instability could be reduced in 18 patients (90?%). Pronation/supination of the wrist was not restricted postoperatively.     

Technique of anatomical footprint reconstruction of the ACL with oval tunnels and medial portal aimers

Purpose

The purpose of this article was to demonstrate an anterior cruciate ligament (ACL) reconstruction technique using oval tunnels. Aim of this single bundle technique is to fit the footprint anatomy of the ACL as closely as possible.

Technique and patients

The presented technique is a single bundle technique using a semitendinosus graft. For femoral tunnel placement, a specific medial portal aimer (Karl Storz, Tuttlingen, Germany) is used. Aiming and drilling of the femoral tunnel are performed via the medial portal. Oval tunnels are created by stepwise dilatation with ovally shaped dilatators. The position of the femoral tunnel is visualized and controlled with the arthroscope via the medial portal. For the tibial tunnel placement, a specific aimer was used as well. With this technique, 24 patients were operated and all intra- and postoperative complications were analyzed prospectively. The tunnel position was documented postoperatively by CT scan.

Results

There were no significant intra- and postoperative complications associated with the oval tunnel technique. The postoperative 3D CT scan revealed that all femoral and tibial tunnels were located within the area of the anatomical ACL insertions.

Conclusions

This article presents an ACL reconstruction technique using oval dilatators and medial portal aimers to create oval tunnels. These oval tunnels match the insertion site anatomy much closer than round tunnels do.

Level of Evidence

Level IV, case series.     

Biomechanical comparison of transosseous re-fixation of the deep fibres of the distal radioulnar ligaments versus deep and superficial fibres: a cadaver study

Purpose

We hypothesized that the re-fixation of the deep and superficial fibres of the distal radioulnar ligaments provide improved stability compared to reconstruction of the deep fibres alone.

Methods

Fourteen fresh-frozen cadaver upper extremities were used for biomechanical testing. Transosseous re-fixation of the deep fibres of the distal radioulnar ligaments alone (single mattress suture group; n?=?7) was compared to the transosseous re-attachment of the deep and superficial fibres (double mattress suture group; n?=?7). Cyclic load application provoked palmar translation of the radius with respect to the rigidly affixed ulna. Creep, stiffness, and hysteresis were obtained from the load-deformation curves, respectively. Testing was done in neutral forearm rotation, 60° pronation, and 60° supination.

Results

The re-fixation techniques did not differ significantly regarding the viscoelastic parameters creep, hysteresis, and stiffness. Several significant differences of one cycle to the consecutive one within each re-fixation group could be detected especially for creep and hysteresis. No significant differences between the different forearm positions could be detected for each viscoelastic parameter.

Conclusions

The re-fixation techniques did not differ significantly regarding creep, hysteresis, and stiffness. This means that the additional re-attachment of the superficial fibres may not provide greater stability to the DRUJ. Bearing in mind that the study was a cadaver examination with a limited number of specimens we may suppose that the re-attachment of the superficial fibres seem to be unnecessary. A gradual decline of creep and hysteresis from first to last loading-unloading cycle is to be expected and typical of ligaments which are viscoelastic.

     

Arthroscopic treatment for ulnar-sided TFCC-tears

Objective

Ruptures of ulnar-sided triangular fibrocartilaginous complex (TFCC) often occur in cases of trauma. Golden standard for diagnosis is the arthroscopy of the wrist. TFCC lesions are classified according to their location if traumatic in origin or if degenerative according to their severity.

Materials and methods

Recent literature has focused on the ruptures of ulnar-sided triangular fibrocartilaginous complex. This article describes conservative, operative and arthroscopic surgical techniques to reconstruct the triangular fibrocartilaginous complex and restore distal radioulnar joint stability.

Results

The main therapeutic goal should be the stabilization of the DRUJ by reattachment of the torn ligaments in ulnar-sided ruptures to the deep fibers in the fovea. This reinsertion can be performed by transosseous suture, a suture anchor or open.

Conclusion

Central TFCC tears are typically located close to the sigmoid notch of the radius and are either traumatic or degenerative in origin. While central TFCC lesions are usually treated by arthroscopic debridement using small joint punches or a bipolar high frequency system, the ulnar TFCC avulsions can also be refixed arthroscopically in different techniques.

     

Editorial Commentary: Guidelines for Wrist Triangular Fibrocartilage Complex Foveal Tears: A Compass for a Broad Voyage

The ulnar head attachment of triangular fibrocartilage complex is divided into 2 sections: the distal radioulnar ligament consists of superficial and deep bundles on both the palmar and dorsal sides, which attach at the fovea and the base of the ulnar styloid. A tear on the ulnar side of triangular fibrocartilage complex inevitably occurs at these attachments. Both magnetic resonance imaging and distal radioulnar joint (DRUJ) arthroscopy are crucial. DRUJ arthroscopy can clarify the tear location. An ulnar styloid tear can be treated by capsular repair. However, a foveal tear should be reattached to the fovea because this tear could cause gross DRUJ instability. There are several ways to reattach the bundles to the fovea, including single- or double-tunnel or bone anchors, and open versus arthroscopic.     

The "wafer" procedure. Partial distal ulnar resection.

A technique of partial resection of the distal ulna ("wafer" procedure) for the treatment of patients with symptomatic tears of the triangular fibrocartilage complex or mild ulnar impaction syndrome or both is described. The distal 2-4 mm of the distal ulna is resected while preserving the distal radioulnar joint and the styloid process of the ulna and the ligaments attached to it. The triangular fibrocartilage can be debrided, repaired, or partially excised. The wafer procedure has several advantages and avoids some of the potential complications of other treatment methods.     

Arthroskopische Auff��llung von fehlplatzierten und erweiterten Bohrkan?len mit Beckenkammspongiosa bei Rezidivinstabilit?t nach Ersatzplastik des vorderen Kreuzbandes

Objective

Arhroscopically performed autologous bone grafting of the femoral or tibial tunnel after anterior cruciate ligament (ACL) reconstruction in symptomatic anterior knee instability.

Indications

Subjective and objective instability in cases with recurrent instability following ACL reconstruction with tibial or femoral tunnel malplacement and tunnel widening.

Contraindications

Open growth plates, severe osteoarthritic changes.

Surgical technique

Arthroscopic ACL graft resection and implant removal followed by debridement of the tunnel and the sclerotic tunnel walls. Cortical bone cylinders and cancellous bone grafts are harvested from the iliac crest and transplanted into the enlarged and malplaced tunnels. The harvest site may be filled with bone substitutes.

Results

Arthroscopic filling of malplaced or enlarged bone tunnels was performed in 42?patients (14?men, 28?women, age range 18?C37?years) with recurrent instability after ACL reconstruction. All patients presented with tunnel malplacement, while 38?patients also had tunnel widening. In 39?cases, a tibial bone graft was necessary; in 12?cases the femoral defect was filled with autologous bone. No complications, such as hematomas of infections, were observed. CT scans showed complete integration of the osseous grafts after 3?C6?months.     

Immunohistochemical Mapping of Sensory Nerve Endings in the Human Triangular Fibrocartilage Complex

Background

The triangular fibrocartilage complex is the main stabilizer of the distal radioulnar joint. While static joint stability is constituted by osseous and ligamentous integrity, the dynamic aspects of joint stability chiefly concern proprioceptive control of the compressive and directional muscular forces acting on the joint. Therefore, an investigation of the pattern and types of sensory nerve endings gives more insight in dynamic distal radioulnar joint stability.

Questions/purposes

We aimed to (1) analyze the general distribution of sensory nerve endings and blood vessels; (2) examine interstructural distribution of sensory nerve endings and blood vessels; (3) compare the number and types of mechanoreceptors in each part; and (4) analyze intrastructural distribution of nerve endings at different tissue depth.

Methods

The subsheath of the extensor carpi ulnaris tendon sheath, the ulnocarpal meniscoid, the articular disc, the dorsal and volar radioulnar ligaments, and the ulnolunate and ulnotriquetral ligaments were dissected from 11 human cadaver wrists. Sensory nerve endings were counted in five levels per specimen as total cell amount/cm² after staining with low-affinity neurotrophin receptor p75, protein gene product 9.5, and S-100 protein and thereafter classified according to Freeman and Wyke.

Results

All types of sensory corpuscles were found in the various structures of the triangular fibrocartilage complex with the exception of the ulnolunate ligament, which contained only Golgi-like endings, free nerve endings, and unclassifiable corpuscles. The articular disc had only free nerve endings. Furthermore, free nerve endings were the predominant sensory nerve ending (median, 72.6/cm²; range, 0–469.4/cm²) and more prevalent than all other types of mechanoreceptors: Ruffini (median, 0; range, 0–5.6/cm²; difference of medians, 72.6; p < 0.001), Pacini (median, 0; range, 0–3.8/cm²; difference of medians, 72.6; p < 0.001), Golgi-like (median, 0; range, 0–2.1/cm²; difference of medians, 72.6; p < 0.001), and unclassifiable corpuscles (median, 0; range, 0–2.5/cm²; difference of medians, 72.6; p < 0.001). The articular disc contained fewer free nerve endings (median, 1.8; range, 0–17.8/cm²) and fewer blood vessels (median, 29.8; range, 0–112.2/cm²; difference of medians: 255.9) than all other structures of the triangular fibrocartilage complex (p ≤ 0.001, respectively) except the ulnolunate ligament. More blood vessels were seen in the volar radioulnar ligament (median, 363.62; range, 117.8–871.8/cm²) compared with the ulnolunate ligament (median, 107.7; range, 15.9–410.3/cm²; difference of medians: 255.91; p = 0.002) and the dorsal radioulnar ligament (median, 116.2; range, 53.9–185.1/cm²; difference of medians: 247.47; p = 0.001). Free nerve endings were obtained in each structure more often than all other types of sensory nerve endings (p < 0.001, respectively). The intrastructural analysis revealed no differences in mechanoreceptor distribution in all investigated specimens with the numbers available, showing a homogenous distribution of proprioceptive qualities in all seven parts of the triangular fibrocartilage complex.

Conclusions

Nociception has a primary proprioceptive role in the neuromuscular stability of the distal radioulnar joint. The articular disc and ulnolunate ligament rarely are innervated, which implies mainly mechanical functions, whereas all other structures have pronounced proprioceptive qualities, prerequisite for dynamic joint stability.

Clinical Relevance

Lesions of the volar and dorsal radioulnar ligaments have immense consequences not only for mechanical but also for dynamic stability of the distal radioulnar joint, and surgical reconstruction in instances of radioulnar ligament injury is important.     

Open repair of the ulnar disruption of the triangular fibrocartilage complex with double three-dimensional mattress suturing technique

Open repair technique of the ulnar disruption of the triangular fibrocartilage complex is described. This technique is indicated for a fresh or a relatively fresh (less than 1 year after the initial injury) ulnar foveal detachment tear, horizontal tear, and proximal slit tear of the triangular fibrocartilage complex, all of which are accompanied by severe dorsal, palmar, or multidirectional instability of the distal radioulnar joint. A chronic tear greater than 1 year from initial injury and a fresh triangular fibrocartilage complex tear without distal radioulnar joint instability, such as central slit tear, are excluded from our indications. A dorsal C-shaped skin incision, a longitudinal incision of the radial edge of the extensor carpi ulnaris subsheath and the dorsal distal radioulnar joint capsule, exposes the distal radioulnar joint. A small, 5-mm longitudinal incision at the origin of the radioulnar ligament exposes its fovea detachment and/or the proximal slit tear of the triangular fibrocartilage complex. The disrupted radioulnar ligament is sutured in a pullout fashion to the ulna with a 3-dimensional double mattress technique through 2 bone tunnels that is precisely made at the central portion of the fovea with 1.2-mm K-wire. An additional horizontal mattress suture is used for closure of the small incision made at the radioulnar ligament, then the extensor carpi ulnaris is repaired. This open-repair technique is complex and requires precise technical skills; however, early results have been more rewarding than the conservative treatment.     

Reconstruction of the ulnar head with a vascularized second metatarsal head: case report

A case of a young patient with avascular necrosis of the ulnar head following a severely displaced ulnar head fracture is presented. Treatment included debridement of the entire ulnar head, leaving the ulnar styloid, sigmoid notch, triangular fibrocartilage, and both distal radioulnar ligaments intact. The head of the ulna was reconstructed by transferring a vascularized second metatarsal head. At 4-year follow-up, the patient had a pain-free wrist with 45° active pronation and 65° supination. He resumed working without limitations as a manual laborer. We conclude that ulnar head reconstruction with a vascularized second metatarsal head is worthwhile in the setting of an unreconstructable traumatic defect, particularly when the sigmoid notch and distal radioulnar ligaments are preserved.     

Anatomical reconstruction of the lateral ligaments of the ankle with semitendinosus allograft

Purpose

The purpose of our study is to evaluate the clinical results of anatomical reconstruction of the lateral ligaments with semitendinosus allograft.

Methods

Thirty-six patients with chronic lateral instability underwent anatomical reconstruction of the lateral ligaments of the ankle with semitendinosus allograft. The American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale score (AOFAS score) and the Karlsson score were used to evaluate the clinical results before and after surgery.

Results

A total of 35 patients (97.2?%) (36 ankles) were followed up for a mean of 37.9?months. The mean AOFAS score improved from 42.3?±?4.9 points preoperatively to 90.4?±?6.7 postoperatively. The mean Karlsson score improved from 38.5?±?3.2 preoperatively to 90.1?±?7.8 postoperatively.

Conclusions

Anatomical reconstruction of the lateral ligaments with semitendinosus allograft achieves a satisfactory surgical outcome for chronic ankle instability.     

Isolierter Bündelersatz bei Partialruptur des vorderen Kreuzbandes

Objective

Partial augmentation of isolated tears of the anteromedial and posterolateral bundle of the anterior cruciate ligament (ACL) with autologous hamstring tendons. The intact fibers of the ACL are preserved.

Indications

Symptomatic isolated tear of the anteromedial or posteromedial bundle of the ACL or rotational instability after ACL reconstruction with malplaced tunnels (e.g., high femoral position)

Contraindications

In revision cases: loss of motion due to malplaced ACL and excessive tunnel widening of the present tunnels with the risk of tunnel confluence.

Surgical technique

Examination of anterior–posterior translation and rotational instability under anesthesia. Diagnostic arthroscopy, repetition of the clinical examination under direct visualization of the ACL, meticulous probing of the functional bundles. Resection of ligament remnants, preparation/preservation of the femoral and tibial footprint. Harvesting one of the hamstring tendons, graft preparation. Positioning of a 2.4 mm K-wire in the anatomic center of the femoral anteromedial/posterolateral bundle insertion, cannulated drilling according to the graft diameter. Positioning of a 2.4 mm K-wire balanced according to the femoral tunnel at the tibia, cannulated drilling. Insertion of the graft and fixation.

Postoperative management

Analogous to that for ACL reconstruction.     

Histologic anatomy of the triangular fibrocartilage.

The collagen arrangement of the triangular fibrocartilage complex was studied in 20 fresh cadaver wrists by means of standard and polarized light microscopy and scanning electron microscopy. The collagen fibres in the articular disk are arranged in undulating sheets oriented at oblique angles to each other. The fibers of the radioulnar ligaments are oriented longitudinally from the radial origin to the ulnar insertion. The origin of the articular disk from the radius is characterized by thick fibers 1 to 2 mm in length radiating from the radius into the articular disk. Five specimens were also injected with india ink. The radioulnar ligaments and the peripheral 15% to 20% of the articular disk are well vascularized, whereas the central 80% of the articular disk is avascular.     

Pathomechanisms of ulnar ligament lesions of the wrist in a cadaveric distal radius fracture model

Background and purpose

Mechanisms of injury to ulnar-sided ligaments (stabilizing the distal radioulnar joint and the ulna to the carpus) associated with dorsally displaced distal radius fractures are poorly described. We investigated the injury patterns in a human cadaver fracture model.

Methods

Fresh frozen human cadaver arms were used. A dorsal open-wedge osteotomy was performed in the distal radius. In 8 specimens, pressure was applied to the palm with the wrist in dorsiflexion and ulnar-sided stabilizing structures subsequently severed. Dorsal angulation was measured on digitized radiographs. In 8 other specimens, the triangular fibrocartilage complex (TFCC) was forced into rupture by axially loading the forearm with the wrist in dorsiflexion. The ulnar side was dissected and injuries were recorded.

Results

Intact ulnar soft tissues limited the dorsal angulation of the distal radius fragment to a median of 32^o (16–34). A combination of bending and shearing of the distal radius fragment was needed to create TFCC injuries. Both palmar and dorsal injuries were observed simultaneously in 6 of 8 specimens.

Interpretation

A TFCC injury can be expected when dorsal angulation of a distal radius fracture exceeds 32^o. The extensor carpi ulnaris subsheath may be a functionally integral part of the TFCC. Both dorsal and palmar structures can tear simultaneously. These findings may have implications for reconstruction of ulnar sided soft tissue injuries.A complex of ligaments on the ulnar side of the wrist supports the stability of the ulnocarpal and the distal radioulnar (DRU) joints. Included in this are the extensor carpi ulnaris (ECU) subsheath and the triangular fibrocartilage complex (TFCC), which is further subdivided into the radioulnar ligaments (RULs), the ulnotriquetral ligament (UT), and the ulnolunate (UL) ligament (Garcia-Elias 1998, Berger 2001). Injuries to the TFCC are common in dorsally angulated fractures of the distal radius fracture (Colle''s fracture) and may adversely affect functional outcome (Lindau et al. 2000). The pathomechanics of these injuries are poorly studied, however.During wrist arthroscopy, we have observed two lesions that are often present when treating TFCC lesions associated with distal radius fractures: (1) a separation of the floor of the ECU tendon sheath from the TFCC, and (2) an injury to the foveal insertion of the TFCC into the ulna. It seems probable that there must be a limit to how much the distal radius fragment can be displaced without rupture of the TFCC or fracture of the ulna.We investigated the characteristics of a TFCC injury in a cadaveric fracture model of dorsally displaced fractures. We hypothesized that (1) a TFCC lesion can be expected at a certain degree of displacement and that (2) a rupture of the foveal insertion would begin in the palmar capsule and progress dorsally, due to the dorsal displacement of the distal radius fragment.     

The interference of distal humeral plating with the medial and lateral collateral ligaments of the elbow

Introduction

The aim of the present study was to determine the anatomical relationship and evaluate the potential interference of today’s common distal humerus plates with the medial and lateral collateral ligaments of the elbow.

Materials and methods

The elbow joints of 23 embalmed upper extremities were dissected. Three different brands of distal humerus double-plating systems were applied in a standardized fashion. We used a caliper to measure the amount of absolute overlap of the plates on the corresponding collateral ligaments.

Results

The data show contact and overlap with the medial and lateral collateral ligaments in all tested medial and lateral plates. The posterolateral and posteromedial plates showed no contact with the ligaments, yet they did contact the posterior joint capsules. The medial plates showed less contact/overlap when compared with the lateral and extended medial plates.

Conclusion

Based on the present data, we conclude that distal humerus plating using the perpendicular technique with standard-sized medial plates shows the least amount of overlap over the medial and lateral collateral ligaments. The extent of the overlap of the ligaments by the humeral plates is clearly shown in the present study.     

Origins and insertions of the triangular fibrocartilage complex: a histological study

The origins and insertions of the triangular fibrocartilage complex (TFCC) were examined histologically in serially sectioned fresh-frozen cadaver wrists. The radioulnar ligament arose vertically through Sharpey's fibres from a broad area in the ulnar fovea and more horizontally from a narrow area at the base of the ulnar styloid. The floor of the extensor carpi ulnaris sheath also originated firmly from the dorsal side of the fovea of the ulna, through an arrangement of Sharpey's fibres. Loose ulnocarpally oriented fibres, corresponding to a thickened ulnar joint capsule, arose from the hyaline-like cartilage matrix at the tip of the ulnar styloid and inserted onto the triquetrum without Sharpey's fibres. The ulnolunate and ulnotriquetral ligaments originated not from the ulna, but from the palmar side of the TFCC. The insertion of the TFCC into the sigmoid notch of the radius demonstrated a central transition from the fibrocartilaginous disc into hyaline cartilage and a firmer fibroosseous transition of the dorsal and palmar portions of the radioulnar ligament at the periphery.     

Unbehandelter Abriss des Processus styloideus ulnae

Background

There are well-defined criteria for the treatment of distal radius fractures but the impact of an unrepaired fracture of the styloid process of the ulnar on recovery after operative treatment is uncertain. This study evaluated radiological and functional results after different operative treatment procedures of distal radius fractures in patients with an untreated fracture of the styloid process of the ulna and those without such a fracture.

Methods

Out of 480 patients with operatively treated distal radius fractures 238 were examined at least 1 year after injury. The fracture of the styloid process of the ulna was not repaired. Three groups (patients without a fracture of the styloid process of the ulna, patients with a tip fracture and those with a basal fracture) were evaluated by multivariate analysis (MANOVA) in order to detect influences of the fracture of the styloid process of the ulna on the radiological and functional results.

Results

Neither the existence nor the location of the fracture of the styloid process of the ulna had a significant effect on the radiological and functional results (p_function=0,849, p_radiology=0,330, p_scores=0,426, MANOVA).

Conclusions

The repair of a fracture of the styloid process of the ulna is not necessary if reduction and fixation of the distal radius fracture is anatomical and stable.     

Longitudinal split tears of the ulnotriquetral ligament

Unlike tears of the peripheral triangular fibrocartilage or avulsions of the distal radioulnar ligaments, longitudinal split tears of the ulnotriquetral (UT) ligament do not cause any instability to the distal radioulnar joint or the ulnocarpal articulation. It is mainly a pain syndrome that can be incapacitating. However, because the UT ligament arises from the palmar radioulnar ligament of the triangular fibrocartilage complex (TFCC), it is by definition, an injury of the TFCC. The purpose of this article is to describe the cause of chronic ulnar wrist pain arising from a longitudinal split tear of the UT ligament.