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Longitudinal Split Tears of the Ulnotriquetral Ligament
Longitudinal Split Tears of the Ulnotriquetral Ligament Brad T. Hyatt, MD, and Peter C. Rhee, DO, MS A tear of the ulnotriquetral (UT) ligament can be a troubling source of pain for the athlete, especially those participating in racquet and batting sports. The UT ligament originates from the TFCC and ulnar styloid and is typically injured when an axial load is applied to an extended wrist with forearm supination. The diagnosis is based on physical exam, specifically the ulnar fovea sign. The stability of the distal radioulnar joint (DRUJ) differentiates a longitudinal split tear of the UT ligament from a TFCC foveal tear. The utility of radiographic imaging is primarily to rule out other causes of ulnar-sided wrist pain. Once a UT ligament tear has been suspected by history and examination, the diagnosis can be confirmed arthroscopically, and one or two sutures are typically sufficient for repair. Arthroscopic repair leads to excellent results with return to full athletic participation. Oper Tech Sports Med 24:126-130 Published by Elsevier Inc. KEYWORDS scaphoid fracture, nondisplaced scaphoid fracture, percutaneous scaphoid fixation, athlete scaphoid fracture
Introduction
W
rist pain can be debilitating to an athlete because of apprehension and weakness. The frustration from missed participation is often exacerbated by an examination and radiographic workup that yield no specific diagnosis. A longitudinal split tear of the ulnotriquetral (UT) ligament should be considered in athletes with ulnar-sided wrist pain. Athletes especially at risk for a UT ligament tear are those with repetitive forearm supination or pronation and wrist extension, such as participants in racquet, club, and batting sports. A fall onto an extended wrist can also cause a UT ligament tear. UT ligament split tears are related to triangular fibrocartilage complex (TFCC) tears by both anatomy and mechanism, but they represent a distinct entity that has characteristic history and physical examination findings. Fortunately, excellent results have been reported for young, active patients who have
Department of Orthopedic Surgery, San Antonio Military Medical Center, Fort Sam Houston, TX. Address reprint requests to Peter Charles Rhee, DO, MS, Department of Orthopedic Surgery, San Antonio Military Medical Center, 3551 Roger Brooke Dr, Fort Sam Houston, Fort Sam Houston, TX 78234. E-mail: [email protected]
126
http://dx.doi.org/10.1053/j.otsm.2016.01.004 1060-1872//Published by Elsevier Inc.
undergone repair.1 The goal of this article is to discuss the anatomy, diagnosis, and treatment algorithm for longitudinal split tears in the active patient.
Anatomy Similar to other extrinsic wrist ligaments, the UT ligament is a nondiscrete thickening of the wrist capsule, which consists of longitudinally oriented collagen fibers.2-5 The UT ligament is one of the primary stabilizers of the ulnar side of the wrist, the other 2 ulnocarpal ligaments being the ulnocapitate and the ulnolunate (UL) ligaments.2,5 In healthy patients, the UT ligament measures 13.2 ⫾ 3.6 mm in length.6 The UT ligament originates from the TFCC, specifically the palmar radioulnar ligament and the palmar aspect of the ulnar styloid. It inserts onto the palmar ulnar aspect of the triquetrum. As the UT and UL ligaments can appear as a confluent structure, the following 2 characteristics help differentiate them: each ligament's site of insertion and the UT's more oblique orientation of fibers compared with the more longitudinal orientation of the UL ligament (Fig. 1).1,2 Alternatively, Sasao et al4 found the UL and UT ligaments to be indivisible in 77 cadaveric wrists and suggest referring to the UL and UT as one, the ulnocarpal ligament. Overall, 2 perforations are often found in the healthy
Longitudinal split tears
127 shared between both injuries, the UT ligament fails at a force below the threshold required to produce a TFCC tear.1,8 Berger suggests the following 3 reasons why the UT ligament splits longitudinally in a characteristic pattern: (1) forces transmitted through the ligament include both longitudinal traction and countertorsion; (2) the perforations from the prestyloid recess and pisotriquetral orifice create a longitudinal path of relative weakness; and (3) the discrete origins of the UT ligament from the palmar radioulnar ligament and ulnar styloid lead to differential of force transmission.1
Figure 1 Anatomy of the ulnotriquetral ligament. Ulnotriquetral (green), ulnolunate (blue), and palmar radioulnar (yellow) ligaments. (Color version of figure is available online.)
History and Examination An injury to the UT ligament should be a part of the differential for patients presenting with ulnar-sided wrist pain.9 Athletes in particular may complain of pain with backhand swings or follow-through or both, motions involving forearm supination and wrist extension. In the largest published series on UT ligament tears, 23 of 36 patients (64%) reported a discrete traumatic event and 4 (11%) reported repetitive trauma. Of these 27 patients, 26 (96%) described an injury mechanism involving wrist hyperextension and forearm supination.1 This same study found the mean patient age to be 30 years (range: 14-70 years), without sex predilection. All patients had ulnar-sided wrist pain exacerbated by gripping; 80% reported worsening pain with pronosupination. Wrist range of motion is typically normal,1 whereas grip strength is usually decreased. The most important provocative physical examination maneuver for diagnosing UT split tears is the ulnar fovea sign. This is performed with the patient seated, facing the examiner. Both wrists are examined serially. With the elbow flexed 901-1101 and neutral forearm rotation, the examiner presses their thumb into the ulnar fovea, which is bound by the distal ulna and styloid, the flexor carpi ulnaris, and the pisiform (Fig. 2). A positive result requires both (1) exquisite tenderness
UT ligament, labeled the prestyloid recess and the pisotriquetral orifice.5
Biomechanics and Injury Biomechanics of the normal and injured UT ligament continue to be elucidated. Radiographic studies have shown the UT ligament to be longest with wrist extension and radial deviation, consistent with the extension phase of the dartthrowing motion.6-8 Using length as a surrogate for tension, the UT ligament is believed to be tensioned and at highest risk of injury with wrist radial deviation and extension.1,6,8 Additionally, a cadaveric model showed that the tension with the UT ligament was doubled in supination compared with pronation.7 In this context, the UT ligament is subject to failure with a combination of axial loading, wrist extension, radial deviation, and forearm supination. However, this mechanism of injury is also implicated in the pathogenesis of TFCC injuries. It is postulated that although the mechanism is
A
B
Figure 2 Ulnar fovea sign. The examiner's thumb is placed at the region of the fovea which is defined by the ulnar styloid, pisiform (drawn), flexor carpi ulnaris (drawn), and the ulnar head (A). The examination reveals positive result indicating reproduction of the patient's pain and markedly worse pain compared with the unaffected wrist. Posteroanterior radiograph of the wrist illustrates the region of the foveal that is palpated with the ulnar fovea test (B). (Color version of figure is available online.)
B.T. Hyatt, P.C. Rhee
128 that recreates the patient's presenting pain and (2) greater pain than the contralateral side. As a tear of the foveal attachment of the TFCC can also result in a positive ulnar fovea sign, the stability of the distal radioulnar joint (DRUJ) must be tested. With the patient in the same position as for the ulnar fovea sign, the examiner stabilizes the ulna 4 cm proximal to the DRUJ and gently attempts volar and dorsal displacement of the distal radius. This is performed in supination, pronation, and neutral forearm rotation and is compared with the unaffected extremity for asymmetry.9 In a retrospective study of 272 patients undergoing wrist arthroscopy, 56 patients (20.6%) were found to have UT ligament tears. The preoperative sensitivity and specificity of the ulnar fovea sign for predicting UT ligament tears was 89.5% and 87.8%, respectively, in patients with a clinically stable DRUJ.10
Imaging Plain films of the wrist cannot be used to diagnose longitudinal split tears of the UT ligament, but they should be routinely obtained to rule out other pathology such as an ulnar styloid fracture or nonunion or ulnar positive variance resulting in ulnocarpal impaction syndrome. Additionally, magnetic resonance imaging (MRI) has not been found to aid in the diagnosis of UT ligament tears (Fig. 3). In a study of 60 wrists (including 20 controls) with noncontrast 3-Tesla MR imaging, 2 blinded musculoskeletal radiologists were asked to determine whether a UT split tear was present. All patients had also undergone wrist arthroscopy as the gold standard for diagnosis. For identifying UT split tears, MRI sensitivity was 58% for one reader and 30% for the second, whereas specificity was 30% for both.11 The authors concluded that preoperative MRI is more valuable in ruling out other sources of wrist pain (eg, TFCC tears)12 than diagnosing UT ligament tears.
A
Operative Treatment Using a standard wrist arthroscopy setup, a diagnostic arthroscopy of the radiocarpal and midcarpal joints is performed to identify any other sources for ulnar-sided wrist pain, such as lunate chondromalacia consistent with ulnocarpal impaction (Fig. 4A) or lunotriquetral ligament injury (Fig. 4B) with special attention given to the integrity of the TFCC. Using a 4-5 working portal, the TFCC can be evaluated for the so-called trampoline sign where the surgeon depresses the center of the disk with a probe and observes the tension on the disk and notes the brisk rebound of the disk indicating an intact TFCC when the probe is removed. If any of the normal insertion sites of the TFCC are compromised, the surgeon would note laxity to depression of the disk and an absence of a rebound effect. The foveal attachments of the palmar and dorsal radioulnar ligaments can be hooked with the probe and pulled distally to determine if a foveal disruption is present. The UT ligament is best viewed from the 3-4 portal.1,13 The UT ligament is often obscured by synovial villi (Fig. 5) that need to be debrided with an arthroscopic shaver for adequate assessment. Radial deviation of the wrist can also improve visualization.13 External pressure in the ulnar fovea with the surgeon's thumb can help identify the location of the ligament and reveal the longitudinal tear which appears as a billowing of frayed ligamentous tissue. A longitudinal split tear can then be identified in its characteristic location extending from the prestyloid recess to the pisotriquetral joint (Fig. 6). After adequate debridement of frayed tissue and exposure of healthy appearing ligament, the longitudinal split tear of the UT ligament is repaired using an outside-in technique. A 1-cm longitudinal incision is made just palmar to the extensor carpi ulnaris tendon, typically within the region of a 6U portal, extending from the ulnar styloid process. The basilic vein and the dorsal cutaneous
B
Figure 3 Ulnotriquetral ligament split tear illustrated on magnetic resonance imaging (MRI). Coronal (A) and sagittal (B) T2-weighted MRI images illustration increased signal intensity within the course of the ulnotriquetral ligament (yellow arrow) and the fovea (red arrow). Triquetrum (T) and ulnar head (UH). (Color version of figure is available online.)
Longitudinal split tears
129
A
B
Figure 4 Diagnostic arthroscopy of the radiocarpal and midcarpal joints to rule out any other causes of ulnar-sided wrist pain. Normal lunate proximal-ulnar chondral surface (A) and no evidence of lunotriquetral ligament laxity (B). (Color version of figure is available online.)
branch of the ulnar nerve course adjacent to each other should be identified and protected. A large bore needle (eg, 18 gauge) or a commercial suture passer (eg, Meniscus Mender II system, Smith & Nephew, Andover, MA) is then used to pass 1 or 2 strands of 2-0 polydioxanone suture across the split tear in a horizontal mattress fashion (Fig. 7).1 Tightening these sutures should close down the longitudinal tear and the repair is tested with a probe.
Rehabilitation Postoperatively, the wrist and the forearm should be immobilized with either a sugar-tong splint or posterior splint extending above the elbow with the forearm in neutral rotation. At the first postoperative visit, the patient is transitioned to a long-arm cast for an additional 4 weeks. At 6-week postoperative, a Munster-type orthosis is fabricated and the patient is instructed on home-based active range-of-motion exercises for the forearm and the wrist. Patients can then wean themselves out of the brace without specific activity restrictions by the 3-month postoperative mark.1,13
Figure 5 Synovial villi and inflamed synovial lining overlying the ulnotriquetral ligament. Prestyloid recess (n) marks the ulnar most junction between the proximal radioulnar (PRU) and ulntriquetral (UT) liagments. (Color version of figure is available online.)
Outcomes There are no studies reporting the outcomes of nonoperative treatment of UT ligament tears, likely because of the need for arthroscopy to definitively diagnose the condition.1 In the largest series of UT ligament repairs in the literature, patient satisfaction was 89%. Additionally, 90% of the patients denied limitations on their activities.1 Grip strength and range of motion were not significantly changed postoperatively. The postoperative disabilities of the arm, shoulder, and hand score at an average of 28 months was 7.5 (standard deviation ¼ 9.8) overall; the work-related section subscore was 4.9 and the sports or music subscore was 7.6. Laborers, men, and older patients tended to have better outcome scores.
Conclusion A longitudinal split tear of the UT ligament should be part of the differential diagnosis in patients with ulnar-sided wrist pain, especially in athletes who participate in racquet, club, or batting activities. The UT ligament is intimately connected to the TFCC and is at risk of tearing when the wrist is axially
Figure 6 The 2 longtudinal limbs of the ulnotriquetral (UT) ligament after arthroscopic debridement. Through the 4-5 working portal, the longitudinal split tear (n) is visualized. (Color version of figure is available online.)
130
Figure 7 Repaired ulnotriquetral (UT) ligament split tear. The 2 horizontal mattress 2-0 polydioxanone sutures span the split tear (black line, dotted). (Color version of figure is available online.)
loaded with the wrist in extension and radial deviation and the forearm is in supination. The ulnar fovea sign is the most important physical examination finding, and a UT ligament tear can be differentiated from a TFCC tear by the stability of the DRUJ. Imaging can help exclude other causes of pain. Diagnosis is confirmed with arthroscopy, and the tear can be treated with an outside-in technique similar to that used for peripheral tears of the TFCC.
References 1. Tay SC, Berger RA, Parker WL: Longitudinal split tears of the ulnotriquetral ligament. Hand Clin 26:495-501, 2010
B.T. Hyatt, P.C. Rhee 2. Garcia-Elias M: Soft-tissue anatomy and relationships about the distal ulna. Hand Clin 14:165-176, 1998 3. Ishii S, Palmer AK, Werner FW, et al: An anatomic study of the ligamentous structure of the triangular fibrocartilage complex. J Hand Surg Am 23:977-985, 1998 4. Sasao S, Beppu M, Kihara H, et al: An anatomical study of the ligaments of the ulnar compartment of the wrist. Hand Surg 8:219-226, 2003 5. Berger RA: The anatomy of the ligaments of the wrist and distal radioulnar joints. Clin Orthop Relat Res 383:32-40, 2001 6. Tang JB, Gu XK, Xu J, et al: In vivo length changes of carpal ligaments of the wrist during dart-throwing motion. J Hand Surg Am 36:284-290, 2011 7. DiTano O, Trumble TE, Tencer AF: Biomechanical function of the distal radioulnar and ulnocarpal wrist ligaments. J Hand Surg Am 28:622-627, 2003 8. Moritomo H, Murase T, Arimitsu S, et al: Change in the length of the ulnocarpal ligaments during radiocarpal motion: Possible impact on triangular fibrocartilage complex foveal tears. J Hand Surg Am 33:1278-1286, 2008 9. Rhee PC, Sauvé PS, Lindau T, et al: Examination of the wrist: Ulnar-sided wrist pain due to ligamentous injury. J Hand Surg Am 39:1859-1862, 2014 10. Tay SC, Tomita K, Berger RA: The “ulnar fovea sign” for defining ulnar wrist pain: An analysis of sensitivity and specificity. J Hand Surg Am 32:438-444, 2007 11. Ringler MD, Howe BM, Amrami KK, et al: Utility of magnetic resonance imaging for detection of longitudinal split tear of the ulnotriquetral ligament. J Hand Surg Am 38:1723-1727, 2013 12. Magee T: Comparison of 3-T MRI and arthroscopy of intrinsic wrist ligament and TFCC tears. Am J Roentgenol 192:80-85, 2009 13. Trumble TE, Dodds SD: Peripheral tears of the TFCC: Arthroscopic diagnosis and management, in Slutsky DJ, Nagle DJ (eds): Techniques in Wrist and Hand Arthroscopy (ed 1). Philadelphia, PA, Elsevier, pp 42-53.
Introduction
W
rist pain can be debilitating to an athlete because of apprehension and weakness. The frustration from missed participation is often exacerbated by an examination and radiographic workup that yield no specific diagnosis. A longitudinal split tear of the ulnotriquetral (UT) ligament should be considered in athletes with ulnar-sided wrist pain. Athletes especially at risk for a UT ligament tear are those with repetitive forearm supination or pronation and wrist extension, such as participants in racquet, club, and batting sports. A fall onto an extended wrist can also cause a UT ligament tear. UT ligament split tears are related to triangular fibrocartilage complex (TFCC) tears by both anatomy and mechanism, but they represent a distinct entity that has characteristic history and physical examination findings. Fortunately, excellent results have been reported for young, active patients who have
Department of Orthopedic Surgery, San Antonio Military Medical Center, Fort Sam Houston, TX. Address reprint requests to Peter Charles Rhee, DO, MS, Department of Orthopedic Surgery, San Antonio Military Medical Center, 3551 Roger Brooke Dr, Fort Sam Houston, Fort Sam Houston, TX 78234. E-mail: [email protected]
126
http://dx.doi.org/10.1053/j.otsm.2016.01.004 1060-1872//Published by Elsevier Inc.
undergone repair.1 The goal of this article is to discuss the anatomy, diagnosis, and treatment algorithm for longitudinal split tears in the active patient.
Anatomy Similar to other extrinsic wrist ligaments, the UT ligament is a nondiscrete thickening of the wrist capsule, which consists of longitudinally oriented collagen fibers.2-5 The UT ligament is one of the primary stabilizers of the ulnar side of the wrist, the other 2 ulnocarpal ligaments being the ulnocapitate and the ulnolunate (UL) ligaments.2,5 In healthy patients, the UT ligament measures 13.2 ⫾ 3.6 mm in length.6 The UT ligament originates from the TFCC, specifically the palmar radioulnar ligament and the palmar aspect of the ulnar styloid. It inserts onto the palmar ulnar aspect of the triquetrum. As the UT and UL ligaments can appear as a confluent structure, the following 2 characteristics help differentiate them: each ligament's site of insertion and the UT's more oblique orientation of fibers compared with the more longitudinal orientation of the UL ligament (Fig. 1).1,2 Alternatively, Sasao et al4 found the UL and UT ligaments to be indivisible in 77 cadaveric wrists and suggest referring to the UL and UT as one, the ulnocarpal ligament. Overall, 2 perforations are often found in the healthy
Longitudinal split tears
127 shared between both injuries, the UT ligament fails at a force below the threshold required to produce a TFCC tear.1,8 Berger suggests the following 3 reasons why the UT ligament splits longitudinally in a characteristic pattern: (1) forces transmitted through the ligament include both longitudinal traction and countertorsion; (2) the perforations from the prestyloid recess and pisotriquetral orifice create a longitudinal path of relative weakness; and (3) the discrete origins of the UT ligament from the palmar radioulnar ligament and ulnar styloid lead to differential of force transmission.1
Figure 1 Anatomy of the ulnotriquetral ligament. Ulnotriquetral (green), ulnolunate (blue), and palmar radioulnar (yellow) ligaments. (Color version of figure is available online.)
History and Examination An injury to the UT ligament should be a part of the differential for patients presenting with ulnar-sided wrist pain.9 Athletes in particular may complain of pain with backhand swings or follow-through or both, motions involving forearm supination and wrist extension. In the largest published series on UT ligament tears, 23 of 36 patients (64%) reported a discrete traumatic event and 4 (11%) reported repetitive trauma. Of these 27 patients, 26 (96%) described an injury mechanism involving wrist hyperextension and forearm supination.1 This same study found the mean patient age to be 30 years (range: 14-70 years), without sex predilection. All patients had ulnar-sided wrist pain exacerbated by gripping; 80% reported worsening pain with pronosupination. Wrist range of motion is typically normal,1 whereas grip strength is usually decreased. The most important provocative physical examination maneuver for diagnosing UT split tears is the ulnar fovea sign. This is performed with the patient seated, facing the examiner. Both wrists are examined serially. With the elbow flexed 901-1101 and neutral forearm rotation, the examiner presses their thumb into the ulnar fovea, which is bound by the distal ulna and styloid, the flexor carpi ulnaris, and the pisiform (Fig. 2). A positive result requires both (1) exquisite tenderness
UT ligament, labeled the prestyloid recess and the pisotriquetral orifice.5
Biomechanics and Injury Biomechanics of the normal and injured UT ligament continue to be elucidated. Radiographic studies have shown the UT ligament to be longest with wrist extension and radial deviation, consistent with the extension phase of the dartthrowing motion.6-8 Using length as a surrogate for tension, the UT ligament is believed to be tensioned and at highest risk of injury with wrist radial deviation and extension.1,6,8 Additionally, a cadaveric model showed that the tension with the UT ligament was doubled in supination compared with pronation.7 In this context, the UT ligament is subject to failure with a combination of axial loading, wrist extension, radial deviation, and forearm supination. However, this mechanism of injury is also implicated in the pathogenesis of TFCC injuries. It is postulated that although the mechanism is
A
B
Figure 2 Ulnar fovea sign. The examiner's thumb is placed at the region of the fovea which is defined by the ulnar styloid, pisiform (drawn), flexor carpi ulnaris (drawn), and the ulnar head (A). The examination reveals positive result indicating reproduction of the patient's pain and markedly worse pain compared with the unaffected wrist. Posteroanterior radiograph of the wrist illustrates the region of the foveal that is palpated with the ulnar fovea test (B). (Color version of figure is available online.)
B.T. Hyatt, P.C. Rhee
128 that recreates the patient's presenting pain and (2) greater pain than the contralateral side. As a tear of the foveal attachment of the TFCC can also result in a positive ulnar fovea sign, the stability of the distal radioulnar joint (DRUJ) must be tested. With the patient in the same position as for the ulnar fovea sign, the examiner stabilizes the ulna 4 cm proximal to the DRUJ and gently attempts volar and dorsal displacement of the distal radius. This is performed in supination, pronation, and neutral forearm rotation and is compared with the unaffected extremity for asymmetry.9 In a retrospective study of 272 patients undergoing wrist arthroscopy, 56 patients (20.6%) were found to have UT ligament tears. The preoperative sensitivity and specificity of the ulnar fovea sign for predicting UT ligament tears was 89.5% and 87.8%, respectively, in patients with a clinically stable DRUJ.10
Imaging Plain films of the wrist cannot be used to diagnose longitudinal split tears of the UT ligament, but they should be routinely obtained to rule out other pathology such as an ulnar styloid fracture or nonunion or ulnar positive variance resulting in ulnocarpal impaction syndrome. Additionally, magnetic resonance imaging (MRI) has not been found to aid in the diagnosis of UT ligament tears (Fig. 3). In a study of 60 wrists (including 20 controls) with noncontrast 3-Tesla MR imaging, 2 blinded musculoskeletal radiologists were asked to determine whether a UT split tear was present. All patients had also undergone wrist arthroscopy as the gold standard for diagnosis. For identifying UT split tears, MRI sensitivity was 58% for one reader and 30% for the second, whereas specificity was 30% for both.11 The authors concluded that preoperative MRI is more valuable in ruling out other sources of wrist pain (eg, TFCC tears)12 than diagnosing UT ligament tears.
A
Operative Treatment Using a standard wrist arthroscopy setup, a diagnostic arthroscopy of the radiocarpal and midcarpal joints is performed to identify any other sources for ulnar-sided wrist pain, such as lunate chondromalacia consistent with ulnocarpal impaction (Fig. 4A) or lunotriquetral ligament injury (Fig. 4B) with special attention given to the integrity of the TFCC. Using a 4-5 working portal, the TFCC can be evaluated for the so-called trampoline sign where the surgeon depresses the center of the disk with a probe and observes the tension on the disk and notes the brisk rebound of the disk indicating an intact TFCC when the probe is removed. If any of the normal insertion sites of the TFCC are compromised, the surgeon would note laxity to depression of the disk and an absence of a rebound effect. The foveal attachments of the palmar and dorsal radioulnar ligaments can be hooked with the probe and pulled distally to determine if a foveal disruption is present. The UT ligament is best viewed from the 3-4 portal.1,13 The UT ligament is often obscured by synovial villi (Fig. 5) that need to be debrided with an arthroscopic shaver for adequate assessment. Radial deviation of the wrist can also improve visualization.13 External pressure in the ulnar fovea with the surgeon's thumb can help identify the location of the ligament and reveal the longitudinal tear which appears as a billowing of frayed ligamentous tissue. A longitudinal split tear can then be identified in its characteristic location extending from the prestyloid recess to the pisotriquetral joint (Fig. 6). After adequate debridement of frayed tissue and exposure of healthy appearing ligament, the longitudinal split tear of the UT ligament is repaired using an outside-in technique. A 1-cm longitudinal incision is made just palmar to the extensor carpi ulnaris tendon, typically within the region of a 6U portal, extending from the ulnar styloid process. The basilic vein and the dorsal cutaneous
B
Figure 3 Ulnotriquetral ligament split tear illustrated on magnetic resonance imaging (MRI). Coronal (A) and sagittal (B) T2-weighted MRI images illustration increased signal intensity within the course of the ulnotriquetral ligament (yellow arrow) and the fovea (red arrow). Triquetrum (T) and ulnar head (UH). (Color version of figure is available online.)
Longitudinal split tears
129
A
B
Figure 4 Diagnostic arthroscopy of the radiocarpal and midcarpal joints to rule out any other causes of ulnar-sided wrist pain. Normal lunate proximal-ulnar chondral surface (A) and no evidence of lunotriquetral ligament laxity (B). (Color version of figure is available online.)
branch of the ulnar nerve course adjacent to each other should be identified and protected. A large bore needle (eg, 18 gauge) or a commercial suture passer (eg, Meniscus Mender II system, Smith & Nephew, Andover, MA) is then used to pass 1 or 2 strands of 2-0 polydioxanone suture across the split tear in a horizontal mattress fashion (Fig. 7).1 Tightening these sutures should close down the longitudinal tear and the repair is tested with a probe.
Rehabilitation Postoperatively, the wrist and the forearm should be immobilized with either a sugar-tong splint or posterior splint extending above the elbow with the forearm in neutral rotation. At the first postoperative visit, the patient is transitioned to a long-arm cast for an additional 4 weeks. At 6-week postoperative, a Munster-type orthosis is fabricated and the patient is instructed on home-based active range-of-motion exercises for the forearm and the wrist. Patients can then wean themselves out of the brace without specific activity restrictions by the 3-month postoperative mark.1,13
Figure 5 Synovial villi and inflamed synovial lining overlying the ulnotriquetral ligament. Prestyloid recess (n) marks the ulnar most junction between the proximal radioulnar (PRU) and ulntriquetral (UT) liagments. (Color version of figure is available online.)
Outcomes There are no studies reporting the outcomes of nonoperative treatment of UT ligament tears, likely because of the need for arthroscopy to definitively diagnose the condition.1 In the largest series of UT ligament repairs in the literature, patient satisfaction was 89%. Additionally, 90% of the patients denied limitations on their activities.1 Grip strength and range of motion were not significantly changed postoperatively. The postoperative disabilities of the arm, shoulder, and hand score at an average of 28 months was 7.5 (standard deviation ¼ 9.8) overall; the work-related section subscore was 4.9 and the sports or music subscore was 7.6. Laborers, men, and older patients tended to have better outcome scores.
Conclusion A longitudinal split tear of the UT ligament should be part of the differential diagnosis in patients with ulnar-sided wrist pain, especially in athletes who participate in racquet, club, or batting activities. The UT ligament is intimately connected to the TFCC and is at risk of tearing when the wrist is axially
Figure 6 The 2 longtudinal limbs of the ulnotriquetral (UT) ligament after arthroscopic debridement. Through the 4-5 working portal, the longitudinal split tear (n) is visualized. (Color version of figure is available online.)
130
Figure 7 Repaired ulnotriquetral (UT) ligament split tear. The 2 horizontal mattress 2-0 polydioxanone sutures span the split tear (black line, dotted). (Color version of figure is available online.)
loaded with the wrist in extension and radial deviation and the forearm is in supination. The ulnar fovea sign is the most important physical examination finding, and a UT ligament tear can be differentiated from a TFCC tear by the stability of the DRUJ. Imaging can help exclude other causes of pain. Diagnosis is confirmed with arthroscopy, and the tear can be treated with an outside-in technique similar to that used for peripheral tears of the TFCC.
References 1. Tay SC, Berger RA, Parker WL: Longitudinal split tears of the ulnotriquetral ligament. Hand Clin 26:495-501, 2010
B.T. Hyatt, P.C. Rhee 2. Garcia-Elias M: Soft-tissue anatomy and relationships about the distal ulna. Hand Clin 14:165-176, 1998 3. Ishii S, Palmer AK, Werner FW, et al: An anatomic study of the ligamentous structure of the triangular fibrocartilage complex. J Hand Surg Am 23:977-985, 1998 4. Sasao S, Beppu M, Kihara H, et al: An anatomical study of the ligaments of the ulnar compartment of the wrist. Hand Surg 8:219-226, 2003 5. Berger RA: The anatomy of the ligaments of the wrist and distal radioulnar joints. Clin Orthop Relat Res 383:32-40, 2001 6. Tang JB, Gu XK, Xu J, et al: In vivo length changes of carpal ligaments of the wrist during dart-throwing motion. J Hand Surg Am 36:284-290, 2011 7. DiTano O, Trumble TE, Tencer AF: Biomechanical function of the distal radioulnar and ulnocarpal wrist ligaments. J Hand Surg Am 28:622-627, 2003 8. Moritomo H, Murase T, Arimitsu S, et al: Change in the length of the ulnocarpal ligaments during radiocarpal motion: Possible impact on triangular fibrocartilage complex foveal tears. J Hand Surg Am 33:1278-1286, 2008 9. Rhee PC, Sauvé PS, Lindau T, et al: Examination of the wrist: Ulnar-sided wrist pain due to ligamentous injury. J Hand Surg Am 39:1859-1862, 2014 10. Tay SC, Tomita K, Berger RA: The “ulnar fovea sign” for defining ulnar wrist pain: An analysis of sensitivity and specificity. J Hand Surg Am 32:438-444, 2007 11. Ringler MD, Howe BM, Amrami KK, et al: Utility of magnetic resonance imaging for detection of longitudinal split tear of the ulnotriquetral ligament. J Hand Surg Am 38:1723-1727, 2013 12. Magee T: Comparison of 3-T MRI and arthroscopy of intrinsic wrist ligament and TFCC tears. Am J Roentgenol 192:80-85, 2009 13. Trumble TE, Dodds SD: Peripheral tears of the TFCC: Arthroscopic diagnosis and management, in Slutsky DJ, Nagle DJ (eds): Techniques in Wrist and Hand Arthroscopy (ed 1). Philadelphia, PA, Elsevier, pp 42-53.