Carpal ligamentous disruptions and negative ulnar variance

Negative ulnar variance is a condition in which the ulna is relatively shorter than the radius at the carpus. It was found in 21% of 203 normal wrists. We have observed an increased incidence (49%) of this anomaly in patients with carpal ligamentous instabilities (dorsiflexion instability, palmar flexion instability, scapholunate dissociation with rotary luxation of the scaphoid, and lunate and perilunate dislocations). While the reasons for this association have yet to be adequately delineated, the presence of a negative ulnar variant may serve as an impartial clue to the presence of ligamentous instability. Many carpal instabilities present with subtle radiographic findings requiring careful evaluation of radiographs. Patients with negative ulnar variance and histories suggestive of ligamentous instability should undergo careful radiologic evaluation to assure early diagnosis of carpal disruption.     

舟月骨间韧带在舟月骨屈伸运动中的作用

目的 研究腕关节屈伸运动时舟月骨间韧带(scapholunate interosseous ligament,SLIL)及其各亚区分级切断后对舟、月骨三维运动的影响,从亚区水平对SLIL在舟、月骨三维运动中的作用进行研究.方法 取12例新鲜冰冻成人上肢标本(左、右侧各6例),分为正常组、断SLIL近侧组、断SIIL近侧+背侧组、断SLIL近侧+掌侧组、SLIL全断组(每组6例),采用三维激光扫描及图像重建技术测定在腕关节屈伸运动时舟、月骨的三维运动数据,并进行统计学分析.结果 正常腕关节在做屈伸运动时,舟月骨的活动方向与腕关节一致,但活动幅度不同,舟骨的活动范围要大于月骨的活动范围.同时,舟月骨还伴有尺桡偏(主要是桡偏)及轻度的旋前旋后活动.切断近侧+掌侧或近侧+背侧亚区组,会对舟月骨的三维运动产生影响.全切断SLIL会导致舟骨掌屈度增加,月骨掌屈活动减弱.结论 采用三维激光扫描及图像重建技术可准确测定腕舟月骨的三维活动度.在SLIL亚区水平上进行的研究表明,部分或全部切断SLIL会对舟月骨的屈伸运动产生明显影响,但SLIL近侧亚区在控制舟月骨运动中不起主要作用.     

Percutaneous lateral ulnar collateral ligament reconstruction

Purpose

Open surgical reconstruction of the lateral ulnar collateral ligament is the standard treatment for symptomatic posterolateral rotatory instability of the elbow. It involves dissection and retraction of the lateral elbow muscles, which have been shown to be secondary stabilizers of the lateral elbow. We introduce a new muscle-protecting technique for single-strand lateral ulnar collateral ligament reconstruction and report on the isometry and primary stability when compared with a conventional muscle-splitting procedure. It was hypothesized that percutaneous lateral ulnar collateral ligament reconstruction provided isometry over the range of motion and that stability was comparable with a conventional open procedure.

Methods

In sixteen human cadaver arms, the intact and the lateral collateral ligament complex-deficient situation was tested. Open lateral ulnar collateral ligament reconstruction was performed using a single-strand palmaris graft with humeral and ulnar tenodesis screw fixation. Posterolateral rotational stability was compared with a new reconstruction method, which percutaneously places a single-strand palmaris graft with humeral and ulnar tenodesis screw fixation.

Results

Both open and percutaneous lateral ulnar collateral ligament reconstruction provided isometry over the range of motion and restored posterolateral stability to that of the intact situation. No significant differences between open and percutaneous reconstruction were found.

Conclusions

Percutaneous lateral ulnar collateral ligament reconstruction aims to preserve the lateral elbow muscles and to minimize soft tissue dissection. It has been shown that in an in vitro setup, this new procedure provides isometry over the range of motion and sufficiently restores posterolateral rotatory stability.     

Isolated rotatory subluxation of the carpal navicular.

Rotatory subluxation of the carpal navicular can cause wrist pain and may lead to severe and disabling degenerative changes. Correct diagnosis depends on recognition of the typical roentgenographic signs. Sixteen patients with neither rheumatoid arthritis nor a lunate or a perilunate dislocation had rotatory subluxation in nineteen wrists. Many had only vague or remote histories of trauma. There were a navicular-lunate gap in all nineteen wrists, and foreshortening of the navicular in sixteen wrists, usually with a ring sign. The abnormalities were best demonstrated on well-centered posteroanterior roentgenograms of the wrist with the hand in slight radial deviation. In two patients, wrist arthrography demonstrated abnormal communication between radiocarpal and intercarpal joints.     

Role of MR imaging in chronic wrist pain

Magnetic resonance (MR) imaging for chronic wrist pain is challenging. Correct assessment of the triangular fibrocartilage, hyaline cartilage, ligaments, and tendons has become mandatory for comprehensive decision making in wrist surgery. The MR technique, potential and limits of MR imaging in patients with chronic wrist pain will be discussed. MR arthrography with injection of gadolinium-containing contrast material into the distal radioulnar joint is suggested for evaluation of the triangular fibrocartilage. The clinically meaningful ulnar-sided peripheral tears are otherwise hard to diagnose. The diagnostic performance of MR imaging for interosseous ligament tears varies considerably. The sensitivity for scapholunate ligament tears is consistently better than for lunotriquetral ligament tears. Gadolinium-enhanced MR imaging is considered to be the best technique for detecting established avascularity of bone, but the assessment of the MR results remains challenging. Most cases of ulnar impaction syndrome have characteristic focal signal intensity changes in the ulnar aspect of the lunate. Avascular necrosis of the lunate (Kienböck’s disease) is characterized by signal changes starting in the proximal radial aspect of the lunate. MR imaging is extremely sensitive for occult fractures. Questions arise if occult posttraumatic bone lesions seen on MR images only necessarily require the same treatment as fractures evident on plain films or computed tomography (CT) images. MR imaging and ultrasound are equally effective for detecting occult carpal ganglia. Carpe bossu (carpal boss) is a bony protuberance of a carpometacarpal joint II and III which may be associated with pain.     

Arthrosis of the lunate-capitate joint

Arthrosis of the lunate-capitate (LC) joint was investigated in 44 wrists from 36 patients. The symptomatology was uncharacteristic and most patients were examined because of pain, swelling or decreased function of the wrist. The LC arthrosis seemed to be secondary to trauma in most patients; 26 wrists had an increased distance between the lunate and scaphoid, indicating a rotatory luxation of the scaphoid; 5 had fracture of the scaphoid with pseudarthrosis; one had a radius fracture healed with volar and ulnar compression and 2 had penetrating trauma to the LC joint. The arthrosis was secondary to pathologic changes in the lunate in 3 patients; lunatomalacia in 2 and a cyst fracturing into the LC joint in one. In 7 wrists arthrosis was found in several carpal joints and the LC arthrosis was one of these.     

肘关节后外侧旋转不稳定的解剖与生物力学研究

目的 研究肘关节外侧软组织对维持肘关节后外侧旋转稳定的作用。方法 通过解剖肘关节,观察外侧软组织的形态结构特点;将16侧上肢标本分为两组,通过生物力学试验,研究按顺序切断桡侧软组织结构时肘关节旋转度的变化。结果 肘关节伸肌起始于肱骨外髁的肌腱膜上,肌腱膜部分随肌肉走行成为肌间隔,部分止于尺骨鹰嘴外侧骨面;桡侧副韧止于尺骨冠突的部分为桡侧尺副韧带,其与桡骨环状韧带在尺度上的止点有2种类型。肘关节桡侧副韧带复合体对维持关节外侧稳定的作用约占50％,伸肌及伸肌腱膜的作用约占11％;在桡侧副韧带复合体中,桡侧副韧带（包括桡侧尺副韧带）起主要作用,桡骨环状韧带起协同作用。结论 肘关节后侧旋转不稳定除桡侧副韧带的损伤外,可能还有外侧伸肌及伸肌腱膜的损伤。     

不典型月骨周围脱位的影像表现及鉴别

目的：总结不典型月骨周围脱位影像特点及与相关骨折脱位的鉴别要点。方法本组16例不典型月骨周围脱位均摄有腕关节正侧位片,5例同时行64排CT扫描及重建,仔细观察分析每一病例的影像表现及特点。结果本组16例均为不典型月骨周围后脱位,伴不同程度月骨向前半脱位。单纯不典型月骨周围后脱位10例,其中同时伴舟骨后脱位3例,半脱位2例,无脱位5例,舟骨无脱位病例中,1例正位头舟间隙明显增宽;经舟骨不典型月骨周围脱位6例,除月骨向前半脱位外,舟骨骨折近段亦随月骨向前半脱位。结论单纯不典型月骨周围后脱位均伴有不同程度月骨向前半脱位,可伴或不伴舟骨后脱位;经舟骨不典型月骨周围后脱位,月骨及骨折近段同时向前半脱位。     

Lunate chondromalacia: evaluation of routine MRI sequences

OBJECTIVE: Chondromalacia is a commonly encountered abnormality at arthroscopy and may be responsible for significant clinical symptoms and disability. In the wrist, the most common location for chondromalacia is the lunate bone. Consequently, we sought to study the accuracy of clinical MRI in the assessment of lunate articular cartilage. MATERIALS AND METHODS: MR images of 34 patients who underwent arthroscopy and had an MRI examination within 1 month of surgery were evaluated by two reviewers for the presence and location of lunate cartilage defects and subchondral edema. RESULTS: Lunate cartilage defects were seen on MRI in 10 of the 13 patients with chondromalacia, but these defects were also incorrectly noted in three of 21 of patients without chondromalacia. The visible locations for cartilage defects were the ulnar aspect of the proximal lunate bone (n = 3), radial aspect of the proximal lunate bone (n = 4), ulnar aspect of the distal lunate bone (n = 2), and radial aspect of the distal lunate bone (n = 1). Subchondral marrow edema was observed in six of the 10 patients with chondromalacia seen on MRI; in all six patients, the edema was seen in the same quadrant as the cartilage defect. Marrow edema was detected in one patient without chondromalacia. CONCLUSION: We conclude that lunate chondromalacia can be accurately assessed using routine MRI sequences, although there are occasional false-positive interpretations.     

尺骨撞击综合征的普通X线表现

目的 探讨尺骨撞击综合征的普通X线表现.资料与方法 分析符合临床和X线诊断标准的28例尺骨撞击综合征患者的腕关节正位片,着重分析尺骨头、月骨和三角骨改变.结果 28例患者中,多数患者存在尺骨阳性变异(92.9%).共40块骨出现骨质异常,依次为月骨24块(60%),三角骨10块(25%),尺骨头6块(15%);表现为骨质硬化11块(27.5%)、囊变6块(15%)、硬化和囊变同时存在23块(57.5%).结论 普通X线片对尺骨撞击综合征的诊断有重要的参考价值.     

Sonography of injury of the ulnar collateral ligament of the elbow—initial experience

Objective The purpose of this study is to describe the sonographic appearance of injuries of the ulnar collateral ligament (UCL) of the elbow.Design and patients Eight non-professional male baseball pitchers, ages 13–35 years, with medial elbow pain and clinical suspicion of ulnar collateral ligament injury, were referred for imaging. All eight underwent sonography of the affected and contralateral asymptomatic elbow, and six also underwent MR imaging. Neither valgus stress nor power Doppler was used during the sonographic examinations. Time from onset of symptoms to imaging was 1.5 weeks to 6 months. Three patients had surgical confirmation of their injuries, with time from imaging to surgery of 2 days to 9 months.Results In four patients, the UCL was ruptured, manifest sonographically in three cases as discontinuity of the normally hyperechoic ligament with anechoic fluid in the gap and in one case as non-visualization of the ligament with heterogeneous echogenicity in the expected location of the ligament. Two adolescent patients had avulsions of the UCL from the medial epicondyle, with sonographic demonstration of the avulsed echogenic bony fragment in both cases. One patient had a mild sprain, manifest as mild thickening and decreased echogenicity of the ligament sonographically compared with the contralateral normal elbow, with mild surrounding hypoechoic edema. The eighth patient had a small partial tear of the deep surface of the distal aspect of the ligament, visualized as a hypoechoic focus between the deep surface of the ligament and its ulnar attachment.Conclusion Tears of the ulnar collateral ligament are manifested sonographically as non-visualization of the ligament or alteration of the normal morphology.     

Radiologische Frühdiagnostik der skapholunären Dissoziation (SLD)

The partial tear of the scapholunate ligament (pre-dynamic stage of SLD) as well as the complete tear (dynamic stage) does not lead to carpal malalignment. However, if the completely ruptured ligament is accompanied by lesions of the extrinsic ligaments, both the scaphoid and the lunate are malaligned already at rest (static stage of SLD). Later, osteoarthritis will develop, beginning in the radioscaphoid compartment, progressing to the midcarpal joint, and ending in a carpal collapse (osteoarthrotic stage of SLD). Dynamic SLD is detectable only in stress views and in cinematography. The high utility of MRI for directly visualizing the injured ligament is emphasized: reparation tissue is focally enhanced at the rupture site by intravenously applied contrast agent; the individual segments of the scapholunate ligament can be visualized in direct MR arthrography, therefore allowing differentiation of partial and complete ligamentous tears.     

Nutritialgefäßkanäle

PURPOSE: To find and describe potential MRI criteria of nutrient vessel canals of carpal bones. METHODS AND MATERIAL: 16 wrists of 13 patients with pain and radiographic depiction of cystic changes within the lunate were examined. The MRI protocol included coronal and sagittal T1- and T2-weighted SE sequences (4 mm slices, 120 FOV, 256 x 256 matrix) as well as coronal STIR images. Final diagnosis was confirmed by surgery (n = 5) and follow up. 10 cadaveric ossa lunata were studied to describe size, number, location and shape of nutrient vessel canals. RESULTS: Ganglion cysts (n = 6) showed characteristic signs. In ulnar impaction syndrome (n = 1) small cystic lesions in the lunate were surrounded by a sclerotic rim and located near the proximal ulnar surface. In Kienb?ck's disease (n = 3) cystic components were irregular and surrounded by bone marrow edema. Nutrient vessel canals (n = 7) imaged as 1 to 3 small cystic lesions within the palmar or dorsal subchondral region. CONCLUSION: MRI can aid in differential diagnosis of cystic carpal lesions. Nutrient vessel canals may not be mistaken for pathologic cystic lesions. Carpal ganglion cysts show distinct diagnostic pattern.     

PLRI: posterolateral rotatory instability of the elbow

Recurrent and persistent instability of the elbow has long been a source of confusion and dismay for both patients and physicians. Early recognition after elbow injury and careful attention to soft tissue repair during lateral elbow surgery may diminish the incidence of this condition. Repair and reconstruction of the lateral ulnar collateral ligament (LUCL) now offers practical and often successful solutions for patients with posterolateral rotatory instability (PLRI) of the elbow.     

Study of ulnar variance with high-resolution MRI: correlation with triangular fibrocartilage complex and cartilage of ulnar side of wrist

PURPOSE: To investigate correlations with ulnar variance and the triangular fibrocartilage complex (TFCC) or cartilage of ulnar side of the wrist on high-resolution MRI with a microscopy coil. MATERIALS AND METHODS: We reviewed ulnar variance, TFCC, and cartilage of the ulnar side of the wrist in 93 subjects (29 asymptomatic volunteers and 64 patients with suspected TFCC injury) with high-resolution MRI using a 47-mm microscopy surface coil. All MR images were obtained with a 1.5 T scanner. Coronal 2D gradient recalled echo T(2)*-weighted images were used for analysis. For qualitative analysis we measured ulnar variance, TFCC angle, thickness in the central portion of TFCC disc proper, and cartilage thickness of the lunate and the ulnar head on MRI and calculated the correlation coefficient between measured values. We also examined the relationship between ulnar variance and age or sex. RESULTS: High-resolution MR images clearly demonstrated TFCC and cartilage of the wrist and ulnar variance. The mean ulnar variance on MRI was +0.26 mm (range, -4.59 to +3.71 mm). The mean TFCC angle and TFCC thickness were 23.9 degrees (range, -4.6 to +54.1 degrees ) and 1.11 mm (range, 0.4 to 3.22 mm), respectively. Ulnar variance and TFCC angle were positively correlated (r = 0.84), and ulnar variance and TFCC thickness were negatively correlated (r = -0.71). However, ulnar variance and lunate or ulnar head cartilage thickness were not significantly correlated. CONCLUSION: High-resolution MRI with a microscopy coil is a useful tool for evaluating the relationship between ulnar variance and ulnar side structures.     

Ligamentous and tendinous anatomy of the intermetacarpal and common carpometacarpal joints: evaluation with MR imaging and MR arthrography.

PURPOSE: The purpose of this work was to demonstrate the normal ligamentous and tendinous anatomy of the intermetacarpal (IMC) and common carpometacarpal (CCMC) joints with MRI and MR arthrography. METHOD: MR images of 22 wrists derived from fresh human cadavers were obtained before and after arthrography. The MR imaging features of the ligaments and tendons about the CCMC and IMC joints and the joints themselves were analyzed in a randomized fashion and correlated with those seen on anatomic sections. RESULTS: Six CCMC ligaments were visualized. The dorsal and palmar CCMC ligaments and the pisometacarpal ligament were best visualized in the sagittal plane. The radial and ulnar CCMC collateral ligaments and the capito-third metacarpal ligament were best visualized in the coronal plane. Three main IMC ligaments were observed: a dorsal and a palmar ligament and an interosseous ligament complex. All three ligaments were best visualized in the axial plane. Four tendinous insertions to the metacarpal bases were evident. CONCLUSION: The anatomy of the ligaments and tendinous insertions about the second to fifth IMC and the CCMC joints is well demonstrated by MR imaging and MR arthrography. MR arthrography does not significantly improve the visualization of these complex structures.     

The examination technique and normal morphology of the ligaments in MRT of the wrist

The normal ligamentous anatomy and an efficient examination technique for the wrist are demonstrated with reference to examinations conducted in healthy volunteers. Only the ulnar complex, the radial collateral ligament, the distal intercarpal ligaments and the radial parts of the palmar and dorsal V-ligaments are adequately visualized. Thus, limited specificity means that static high-resolution MRI of the wrist cannot at present be considered an adequate examination method for the evaluation of unexplained wrist pain and instability. So far MRI can only play a key role in the diagnosis of lesions of the ulnar complex.     

Soft Foods for a Sore Mouth

After weight lifting, a 15-year-old boy pain in his right wrist, had tenderness over the dorsum of the lunate, and had limited wrist motion. Radiographs revealed avascular necrosis of the lunate, or Kienböck's disease, and negative ulnar variance. The patient was successfully treated with an ulnar lengthening procedure and immobilization. This patient's symptoms are typical of Kienböck's disease, which should be considered in the differential diagnosis of any active patient who has wrist pain and limited wrist motion. Treatment of this rare disorder can include immobilization for early-stage disease, or surgery, which is most likely to provide an optimal outcome.     

Soft tissue allograft and double-bundle reconstruction

The anterior cruciate ligament (ACL) is composed of two functional bundles, the anteromedial and posterolateral. Multiple biomechanical and clinical studies have demonstrated that the posterolateral bundle plays a critical role in rotatory stability of the knee. Anatomic double-bundle reconstruction of the ACL best restores knee function and kinematics when the ACL is ruptured. For double-bundle ACL reconstruction, the use of allograft is safe, minimizes graft harvest morbidity, expedites recovery, and is associated with successful clinical results in short-term follow-up.     

The carpometacarpal joint of the thumb: MR appearance in asymptomatic volunteers

Purpose

To prospectively characterize the MR appearance of the carpometacarpal (CMC) joint of the thumb in asymptomatic volunteers.

Materials and methods

Thirty-four asymptomatic volunteers (17 women, 17 men, mean age, 33.9?±?9.2 years) underwent MR imaging of the thumb after approval by the local ethical committee. Two musculoskeletal radiologists independently classified visibility and signal intensity (SI) characteristics of the anterior oblique (AOL/beak ligament), the posterior oblique (POL), the intermetacarpal (IML), and the dorsoradial ligaments (DRL) on a three-point Likert scale. The thickness of all ligaments, cartilage integrity, and presence of joint fluid were assessed. The alignment of the first metacarpal base with the trapezium was quantified on sagittal and coronal planes.

Results

The ligaments of the CMC joint were constantly visible in all volunteers for the POL and IML, and in all but one for the AOL and DRL. On intermediate-weighted fat-saturated images the POL (65 %/74 % reader 1/reader 2) and DRL (58 %/64 %) were commonly of increased SI, while the IML had a striated appearance in 91 %/76 % of subjects. The AOL showed a variable SI (36 %/42 % low, 27 %/27 % increased, 36 %/30 % striated). The IML was the thickest ligament with a mean of 2.9 mm/3.1 mm and the DRL the thinnest (1.2 mm/1.4 mm). There was a mean dorsal subluxation of 1.8 mm/2.0 mm and radial subluxation of 2.8 mm/3.4 mm of the metacarpal base. The AOL was significantly thicker in men (1.7 mm) than in women (1.2 mm; p?=?0.02). Radial subluxation was significantly larger in men (3.4 mm) than in women (2.2 mm; p?=?0.02). No subluxation in palmar or ulnar direction was seen.

Conclusions

Radial and dorsal subluxation of the CMC joint can be a normal finding in a resting position at MR imaging. The CMC ligaments showed a considerable variability of signal intensity with a typically striated IML; thickness of the AOL is typically less than 2.2 mm, of the POL typically less than 2.9 mm.