Lunotriquetral Research Articles

Results of Arthroscopic Reduction and Percutaneous Fixation for Acute Displaced Scaphoid Fractures

This study used percutaneous techniques augmented by simultaneous wrist arthroscopy to visualize the fracture and thus confirm the fracture alignment and reduction and also to assesses the concurrent associated ligament injuries. Retrospective study. Arthroscopy was used to help to reduce scaphoid fractures and assess soft-tissue injuries in 15 acute cases (13 male and 2 female patients). The fractures were treated by reduction under arthroscopic control and percutaneous fixation with the cannulated interosseous compression screw. Soft-tissue lesions were also treated at the same time using debridement, suture repair, or K-wire transfixation. The average age of the patients was 29.2 years (range, 19 to 48 years). Two patients (13.3%) had scapholunate (SL) ligament injuries, and both exhibited partial tear of the SL ligament. Four patients (26.7%) suffered lunotriquetral (LT) ligament injuries and received ligament debridement, K-wire fixation of the LT joint, and splinting. Six patients (40%) had chondral fractures. Additionally, the triangular fibrocartilage complex (TFCC) was torn in 5 patients (33%). Finally, 5 patients (33%) suffered radioscaphocapitate ligament or long radiolunate ligament injuries. All fractures healed without malunion or nonunion and, at follow-up of 24 to 28 months, 11 patients had excellent results and 4 had good results based on Mayo Modified Wrist Scores. We believe that arthroscopic reduction may be considered for scaphoid fractures because this approach can use a single procedure to achieve acceptable restoration of fractures as well as assessment and management of soft-tissue lesions. Level IV Therapeutic Study, case series with no, or historical, control group.

Wrist kinetics after luno-triquetral dissociation: the changes in moment arms of the flexor carpi ulnaris tendon

Wrist biomechanics after luno-triquetral (LT) dissociation is important for understanding the clinical sequelae of the disease and for determining its treatment options. The LT interosseous ligament plays an important role in stabilizing the joint and damage to the ligament would be expected to significantly increase moment arms of tendon of the flexor carpi ulnaris (FCU), the principal ulnar wrist flexor. We investigated the changes in moment arms of FCU tendon after various amounts of sectioning of the ligaments proven to be associated with LT dissociation. In six fresh frozen cadaveric upper extremities, excursions of the FCU tendon were recorded simultaneously with wrist joint angulation during wrist flexion-extension and radioulnar deviation. Tendon excursions were measured in intact wrists, in wrists with sectioning of the dorsal portion of the LT interosseous ligament, in wrists with sectioning of the entire LT interosseous ligament, and finally in wrists with further sectioning of the dorsal radiotriquetral and intercarpal ligaments. Moment arms of the tendon were calculated from tendon excursions and joint motion angulations and expressed as percentage changes from those in the intact wrist. During wrist flexion-extension, moment arms of the FCU tendon after sectioning of the entire LT interosseous ligament and after sectioning of the two capsular ligaments were 112±7% and 114±8%, respectively; these values were significantly greater than those in the intact wrist. During radioulnar deviation, the moment arms were 114±11% after sectioning of the dorsal portion of the LT interosseous ligament, 134±15% after sectioning of the entire ligament, and 153±18% after sectioning of the capsular ligaments, again being significantly greater than the normal wrist. Increase in moment arms of the FCU tendon after loss of integrity of the LT interosseous ligament and dorsal capsular ligaments may contribute to clinical sequelae of LT dissociation and difficulty in treating this disorder.

Arthroscopically-assisted reduction of intra-articular fractures and soft tissue management of distal radius.

Arthroscopy was used to help to reduce intra-articular fractures of the distal radius and treat soft tissue injuries in 33 acute cases. The fractures were treated by reduction under arthroscopic control and percutaneous fixation either with or without external fixation. The triangular fibrocartilage complex (TFCC) was torn in 18 of 33 patients (54%). All tears were peripheral and were repaired with arthroscopic procedures. Scapholunate (SL) ligament injuries prevailed in six (18%) patients; most of them exhibited instability in the SL joint. They received SL ligament debrided and transfixed with K-wires. Four (12%) of the patients suffered lunotriquetral (LT) ligament injuries; three of them also received transfixation with K-wires. Six (18%) of the patients exhibited chondral fractures. All fractures healed without measurable incongruity of joint surface and at follow-up (24 to 36 months), 11 patients displayed excellent results and 22 patients displayed good results according to the Mayo modified wrist score.

Wrist arthroscopy for the treatment of ligament and triangular fibrocartilage complex injuries

The use of arthroscopy was evaluated in 47 patients who were treated for suspected triangular fibrocartilage complex (TFCC) tears, scapholunate (SL) tears, and/or lunotriquetral (LT) tears. Wrist arthroscopy was performed using traction and standard portals. Any TFCC tear found was debrided to a stable rim. SL and LT tears were debrided to bleeding bone. The range of follow-up was 1.5 to 50 months (average, 15.4 months). Patient grading was determined usin the Mayo Modified Wrist Score. For the 28 patients with TFCC tears, the results were excellent in 13, good in 8, fair in 2, and poor in 5. For the 23 patients with SL tears, the results were 11, 9, 1, and 2, respectively. Of the 5 patients with LT tears, 1 result was excellent, and 4 were poor. Workers compensation did not affect results. Arthroscopic debridement of SL and TFCC tears has proven effective. Debridement of LT tears has not been as successful. Based on our results, we feel that arthroscopic debridement of SL and TFCC tears is warranted. Arthroscopy 1998 Jul-Aug;14(5):479-83

The lunotriquetral joint: Kinematic effects of sequential ligament sectioning, ligament repair, and arthrodesis

This experiment was conducted to study the effects of sequential sectioning of the ligaments of the lunotriquetral (LT) joint and the effects of simulated repair or arthodesis on kinematics of the wrist joint using an x-ray stereophotogrammetric technique. A 3-dimensional coordinate software program calculated relative motion between bodies as screw axis displacement and rotation about each axis. Sectioning of the proximal and dorsal component of the LT ligament had little effect on carpal kinematics, but sectioning of the proximal and palmar components of the ligament resulted in flexion of both the lunate and triquetrum, producing a volar intercalated segment instability (VISI) pattern. The triquetrum supinated away from the lunate after sectioning of the entire LT ligament. Greater VISI occurred after sectioning the dorsal radiotriquetral and scaphotriquetral ligaments. Progressive destabilization of the LT joint results in increasing kinematic alterations; however, these may not exactly mimic the clinical situation. Moving the wrist through 1,000 cycles increased the instability. Dorsal repair of the LT ligament realigned the lunate and triquetrum, and LT fusion corrected triquetral supination. The latter, however, resulted in overcorrection into extension, which prevented a full wrist extension. The repair used may be insufficient to restore the palmar ligamentous integrity. Lunotriquetral arthodesis was difficult to simulate, providing some insight into the cause of clinical nonunions. Severe VISI is not correctable by repair or arthrodesis and requires further study using reconstructive procedures not discussed here.

The ulnocarpal stress test in the diagnosis of ulnar-sided wrist pain

Forty-five patients with persistent ulnar-sided wrist pain and a positive ulnocarpal stress test were investigated by X-ray, arthrography, 99mTechnetium bone scanning, magnetic resonance imaging and wrist arthroscopy. Ulnar wrist pathology was positively identified in nine of 45 patients by X-ray, 18 of 37 by arthrography, 19 of 27 by bone scan, four of 33 by MRI, and in all 45 patients by arthroscopy. The final diagnosis was ulnocarpal abutment syndrome in 28 patients, traumatic triangular fibrocartilage (TFC) tear in six, lunotriquetral (LT) ligament tear in five, TFC and LT ligament tear in one, wrist arthritis in four and cartilaginous free body in one. The ulnocarpal stress test is a useful provocative test, and a positive test suggests the presence of ulnar-sided wrist pathology. The test is sufficiently sensitive to warrant further investigation by arthroscopy.

Arthroscopic diagnosis of intra-articular soft tissue injuries associated with distal radial fractures

Arthroscopy was used to assess the soft tissue injuries associated with distal radial fractures in 118 acute intra- and extra-articular fractures. The triangular fibrocartilage complex (TFCC) was torn in 46 of 118 patients--in 35% of intra-articular fractures and in 53% of extra-articular fractures. No correlation between ulnar styloid fractures and TFCC injuries could be found. Scapholunate (SL) ligament injuries with instability were present in 21.5% of intra-articular fractures and in 6.7% of extra-articular fractures. Lunotriquetral (LT) ligament injuries with instability were present in 6.7% of intra-articular fractures. and in 13.3% of extra-articular fractures. Combined SL and LT injuries were present in 5.6% of intra-articular fracture. Preoperative radiographs correlated with TFCC injury. Patients with TFCC tears had greater shortening and dorsal angulation on the preoperative radiographs. Preoperative radiographs had no predictive value for interosseous ligament injury. Ligamentous injuries are commonly associated with both intra-articular and extra-articular distal radial fractures.

Lunotriquetral arthrodesis: A controversial procedure

12 male (mean age 28) and 11 female (mean age 32) patients treated with lunotriquetral (LT) arthrodesis were reviewed with a median follow-up of 28 months (range 18-40 months) for this retrospective study. At first presentation 12 patients were unable to work, and at follow-up only three men remained out of work. The relief of pain was significant (P < 0.001) and the median Culp (1993) wrist score obtained 74 (min. 45, max. 96); however, only one patient was totally free of pain and seven men had to change their occupations. Men lost 455 working days, women 191, a highly significant difference (P = 0.006). This loss correlated (P = 0.007) with the LT angle measured in the frontal plane: all patients but one with a LT angle of less than 31 degrees returned to work within 1 year, but only four with a greater angle (P = 0.007). This emphasizes the importance of correct positioning of the triquetrum, which seems hard to achieve with two AO lag screws. Furthermore, even two screws seem unable to ensure solid fusion as shown by the high rate of pseudarthrosis (57%). LT fusion cannot be considered as a routine procedure and results are not yet predictable. According to these results, we feel that a bone graft placed in a slot from lunate to triquetrum is the procedure of choice. In the presence of a chondromalacia in the ulnar midcarpal joint, a four bone fusion is primarily recommended.

A method for measuring tension in small ligaments: an application to the ligaments of the wrist carpus.

A new technique has been devised for measuring the in situ tension in small ligaments. It is based on measuring the tension in an axially loaded flexible cable with pinned endpoints by deflecting the cable laterally and measuring its lateral load and deformation. Studies were performed in which nylon line and bone ligament bone preparations were placed in a materials tester and loaded in axial tension. Axial load as measured by lateral load and deformation was found to agree with the known load to within 8 percent. The method was sensitive to error in determination of ligament length, nonperpendicularity of the laterally applied load to the long axis of the ligament, and when used in situ, impingement of the ligament on a third bone causing bending. A device, consisting of an LVDT mounted to a rigid frame with its core rod connected to a load cell, was developed. The position of the core rod was controlled by a manual screw drive, and a hook on the other end of the core rod was used to deflect the ligament laterally. This device was applied to the study of tensions in five ligaments of the palmar wrist carpus, in seven cadaver specimens. Results showed that the radioscaphocapitate (RSC) and radiolunate (RL) ligaments had significantly greater tensions than the lunotriquetral (LT), the triquetrocapitate (TC), and scaphocapitate (SC) ligaments. For the four positions of the hand tested, neutral, 14 deg radial and 14 deg ulnar deviation, and 28 deg of extension, ligament tensions were found to be unaffected by position.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic wrist pain: spin-echo and short tau inversion recovery MR imaging and conventional and MR arthrography.

The accuracy of T1-, proton-density-, and T2-weighted magnetic resonance (MR) imaging sequences and gadolinium-enhanced MR arthrography in evaluation of the triangular fibro-cartilage complex (TFCC) and the scapholunate (SL) and lunotriquetral (LT) ligaments was studied in 15 patients with chronic wrist pain. Arthrography and arthroscopy were used as standards of reference. Twelve patients also underwent imaging with short tau inversion recovery (STIR) sequences. MR imaging was more reliable in evaluation of the morphology of the TFCC and SL ligament than in that of the LT ligament. With arthrography as the standard, sensitivity was 0.721, specificity was 0.947, and accuracy was 0.887 for the TFCC; these values were 0.500, 0.864, and 0.765 for the SL ligament and 0.519, 0.455, and 0.490 for the LT ligament. No visualization of the SL ligament indicated a tear, but this sign was not helpful in evaluation of the LT ligament. Fluid in the distal radioulnar joint had a high association with TFCC tears. Accuracy with MR arthrography was higher than with the other sequences. STIR images were effective in evaluation of the TFCC. The combination of proton-density-and T2-weighted images appears to be useful because morphologic characteristics and the presence of fluid can be evaluated.

Management of chronic lunotriquetral ligament tears

Treatment of chronic disruptions of the lunotriquetral (LT) ligament is not well-defined. Eleven patients treated by LT fusion with use of a compression screw are reported. The injury frequently resulted from hyperextension of the wrist. Pain on the ulnar side of the wrist, limited motion, and tenderness over the LT joint exacerbated by ballottement were present. Standard radiographs were normal. Arthrography showed the ligamentous tear in all cases. After operation, immobilization was continued until fusion was apparent radiographically. Fusion was achieved in all cases between 2 and 5 months. Four patients were free of pain, four patients had pain only at the extremes of motion, and three patients had persistent pain. Mean wrist motion was as follows (preoperative/postoperative): flexion (53 degrees/45 degrees), extension (60 degrees/49 degrees), radial deviation (17 degrees/21 degrees), and ulnar deviation (25 degrees/18 degrees). Maximum grip strength as a percentage of the uninjured side was 73% preoperatively and 59% postoperatively. LT tears can exist de novo or as part of the ulnar impaction syndrome; a method for differentiation is presented.

Lunotriquetral sprains

Injuries to the ulnar side of the carpus have not been well defined. Lunotriquetral (LT) sprains have only recently been described and are often unrecognized. They usually occur from hyperextension: and twisting of the wrist. Symptoms include pain, weakness, limitation of motion, and a "click" with lateral motions. The sprain may be associated with dorsal subluxation of the ulnar head and supination of the carpus. Physical examination discloses point tenderness, laxity, and often a snap over the LT joint. Dorsopalmar manipulation of the triquetrum on the lunate demonstrates crepitus and laxity. A radiocarpal arthrogram is helpful in confirming the diagnosis. Palmar-flexion instability patterns represent a more extensive continuation of this injury, which then may be termed an LT dissociation. Treatment with adequate immobilization for acute injuries appears to be useful if the diagnosis is established early. Chronic sprains may require stabilization of the LT joint by ligament repair, reconstruction, or LT fusion. Associated injuries, such as carpometacarpal (CMC) or hamulus fractures, have been noted. Results of treatment have varied considerably and depend in part on the severity and chronicity of the condition at the time of recognition.