"Floating thumb metacarpal" or complete dislocation of the thumb metacarpal: a case report and review of the literature

We present a case of a patient with a simultaneous dislocation of the metacarpophalangeal (MP) and the carpometacarpal (CMC) joint of the thumb as an isolated injury, and we review the relevant literature. We found only three previous reports in the literature, two reports as an isolated injury and another similar injury combined with a carpometacarpal fracture-dislocation of all four fingers. A closed reduction of both joints followed by an open repair of the torn ulnar collateral ligament of the MP joint and Kirschner-wire (K-wire) stabilization of the CMC joint led to a good result at 1 year. This rare injury has been described as a "complete dislocation of the thumb metacarpal" or as a "simultaneous dislocation of the MP and CMC joints of the thumb". We suggest it is a "floating thumb metacarpal".     

Corrective osteotomy for malunion of the distal radius

Forty-five patients were reviewed on average 5.7 years after corrective osteotomy for symptomatic distal radius malunion. Restoration of anatomy and function was assessed compared with the contralateral wrist. It was found that osteotomy of the distal radius alone did not completely restore normal anatomy and relieve symptoms, and in several cases a second operation was needed. Osteoarthritic changes in the radiocarpal and radioulnar joints were common, and they correlated with restriction in range of motion, but not with pain. Range of motion and grip power were reduced compared to the unaffected hand, but only loss of supination and ulnar deviation correlated with an unsatisfactory subjective result. The result was good or satisfactory in 33 of the 45 patients. We conclude that reconstructive procedures in patients with distal radius malunion may not completely restore normal function, and every effort should therefore be made to prevent malunion in the treatment of distal radius fractures.     

Degenerative and post-traumatic arthritis affecting the carpometacarpal joints of the fingers

Symptomatic post-traumatic arthritis affecting the finger CMC joints is less common than might otherwise be expected based on the frequency of injury, especially to the fifth CMC joint. For the fifth CMC joint, the shallow concavoconvex articulation combined with the typical fracture location may provide a protective effect. Non-operative measures are typically successful, except in cases of missed fracture/dislocations and symptomatic joint instability. In these instances, re-construction emphasizes stability first, with an eye toward mobility for the ulnar column.It is common to detect a bony prominence in the region of the dorsal second and third CMC joints during examination of the hand. In most instances, the projection is asymptomatic and likely represents an os styloideum [18]. When painful and unresponsive to nonoperative treatments, this carpometacarpal boss can be excised surgically.     

钩骨腕掌关节移位重建指骨间关节的解剖学基础研究

目的探讨钩骨腕掌关节移位、修复和重建手的功能性关节的解剖学基础。方法22侧冷冻成人手腕标本,解剖观测钩骨腕掌关节和中节指骨基底关节面的形态、结构特点,测量各关节面的尺桡径、掌背径、关节面凹面的深度及关节面面积。将所得数据进行统计分析,比较钩骨腕掌关节和中节指骨基底关节面在形态、结构特点、面积及各径线长度的相似度。结果钩骨腕掌关节的尺桡径(13.54mm±1.15mm,钩骨腕掌关节尺桡侧缘中点的距离)和示、中、环指中节与拇指远节指骨基底关节面的尺桡径(关节面尺桡侧缘中点的距离)无统计学差异(P0.01,对应t值分别为2.7670、-2.0720、2.1608、1.2189);钩骨腕掌关节的掌背径(10.71mm±0.93mm,钩骨底嵴的两顶点间距离)和环指中节指骨基底关节面的掌背径(关节面掌背侧缘中点的距离)无统计学差异(P0.01,t=1.6170);钩骨腕掌关节的尺侧凹面深度(1.30±0.08)mm、桡侧凹面深度(0.95±0.05)mm、面积(139.89±5.44)mm2和示、中、环、小指中节指骨、拇指远节指骨基底关节面的凹面深度(尺、桡侧关节面掌背缘中点为支点测量深度)及面积有统计学差异(P0.01)。结论钩骨腕掌关节可作为一个新的良好关节供区,用于修复和重建各中节指骨基底关节面。     

Late compression neuropathies after Colles' fractures

Conservative management of 166 Colles' fractures was associated with a 12% rate of late compression neuropathies (mean follow-up period, 28 months). Compression of the median nerve (8%) was twice as common as ulnar nerve compression (4%). Eighty-five percent of the patients with median nerve compression had malunion with radial collapse with or without other deformities (dorsal angulation/radial displacement). Patients with ulnar nerve compression had either malunion with radial collapse or volar subluxation of the ulnar head in those fractures that healed with dorsal angulation. Patients without nerve complications showed a significantly lower rate of malunions. These results demonstrate that anatomic derangements play a role in the development of late compression neuropathies following Colles' fractures.     

Possibility of the hamatum carpometacarpal joint as a new joint donor site for interphalangeal joint restoration

Objective

This research investigates the anatomic basis for the repair and reconstruction of hand joints using transposition of the carpometacarpal (CMC) joint of the hamatum.

Methods

The morphology and structure of the CMC joints of the hamatum and the base joints of the middle phalanx were observed on 22 freshly frozen wrist specimens at Shanghai 6th People’s Hospital Research Institute of Microsurgery. The volar dorsal dia, radioulnar dia, depth of concave, and area of the joints were measured. Data were obtained through statistical analysis, and the resemblance of joints was compared in terms of morphology, structure, area, length, and diameter.

Results

The radioulnar dia of the CMC joints of the hamatum (13.54 ± 1.15 mm) did not exhibit any evident differences in the middle phalanx of the forefinger, middle finger, and ring finger, and in the distal phalanx of the thumb. The volar dorsal dia of the CMC joints of the hamatum (10.71 ± 0.93 mm) exhibited an evident difference in the middle phalanx of the ring finger. In all fingers, the depth of the ulnar and radial concave of the CMC joints of the hamatum (1.30 ± 0.08 and 0.95 ± 0.05 mm, respectively) and the area of the CMC joints of the hamatum (139.89 ± 5.44 mm²) showed an evident difference.

Conclusion

The CMC joint of the hamatum could be considered a new and viable joint donor site that could be used to repair and reconstruct the base joints of the middle phalanx.     

Failure of active extension after traumatic cubitus varus. A case report

In children cubitus varus is common after malunion of a supracondylar fracture of the humerus. Later problems such as tardy ulnar nerve palsy, snapping of the lateral triceps tendon or ulnar nerve and posterolateral rotatory instability are well documented. We present a case of anteromedial dislocation of the entire triceps tendon with loss of extensor power and describe the method of treatment.     

Degenerative diseases of the metacarpophalangeal joints

Degenerative arthritis of the finger metacarpophalangeal joints is uncommon and, when seen, a specific etiology should be sought. MP joint arthritis in the absence of a history of trauma may signal an underlying systemic disease. The clinical and radiographic findings may be subtle. Once degenerative changes occur, the usual treatment is arthroplasty using a flexible silicone rubber (Swanson) finger joint implant that should provide a relatively stable and painless joint with a functional range of motion. Degenerative arthritis of the thumb MP joint is more common following injuries that damage the ligaments on the ulnar or radial side of the MP joint and which result in lateral instability of the joint. Arthritis of the MP joint also may occur following infection or direct joint injury. Secondary MP arthritis may result from thumb CMC joint disease and must be attended to at the time CMC joint reconstruction is performed. Degenerative disease of the thumb sesamoid bones must be considered in patients with persistent MP joint pain after either trauma or MP joint fusion.     

The human first carpometacarpal joint: osteoarthritic degeneration and 3-dimensional modeling.

The purpose of this study was to gain insight into potential mechanical factors contributing to osteoarthritis of the human first carpometacarpal joint (CMC). This was accomplished by creating three-dimensional (3-D) computer models of the articular surfaces of CMC joints of older humans and by determining their locus of cartilage degeneration. The research questions of this study were: 1) What is the articular wear pattern of cartilage degeneration in CMC osteoarthritis?, (2) Are there significant topographic differences in joint area and contour between the joints of males and females?, and 3) Are there measurable bony joint recesses consistently found within the joint? The articular surfaces of 25 embalmed cadaveric joints (from 13 cadavers) were graded for degree of osteoarthritis, and the location of degeneration was mapped using a dissection microscope. The surfaces of 14 mildly degenerated joints were digitized and reconstructed as 3-D computer models using the Microscribe 3D-X Digitizer and the Rhinoceros 2.0 NURBS Modeling Software. This technology provided accurate and reproducible information on joint area and topography. The dorsoradial trapezial region was found to be significantly more degenerated than other quadrants in both males and females. Mean trapezial articular surface area was 197 mm 2 in males and 160 mm(2) in females; the respective mean areas for the metacarpal were 239 mm(2) in males and 184 mm(2) in females. Joints of females were found to be significantly more concave in radioulnar profile than those of males. Three bony joint recesses were consistently found, two in the radial and ulnar aspects of the trapezium and the third in the palmar surface of the metacarpal.     

Distal radio-ulnar joint subluxation following intramedullary nailing of the radius in a child

We describe a patient with fractures of both bones of the forearm in whom flexible intramedullary nail fixation of the radius alone led to ulnar malunion and a symptomatic distal radio-ulnar joint subluxation. This was successfully treated by ulnar osteotomy.     

尺骨短缩术联合腕关节镜治疗桡骨远端骨折后畸形愈合的疗效分析

目的 探讨采用腕关节镜技术联合尺骨短缩术治疗桡骨远端骨折后畸形愈合的临床效果.方法 2013年9月至2015年9月我院收治桡骨远端骨折后畸形愈合病人67例,根据手术方法分为三组:联合治疗组,35例,采用腕关节镜技术联合尺骨短缩术治疗;尺骨短缩组,21例,采用单一的尺骨短缩术进行治疗;腕关节镜组,11例,采用单一的腕关节镜技术清理关节腔治疗.比较各组治疗后的数字评价量表(numerical rating scale,NRS)疼痛评分和上肢、肩、手功能障碍(disabilities of the arm,shoulder and hand,DASH)腕关节评分.结果 联合治疗组、尺骨短缩组治疗后的NRS疼痛评分分别为(1.32±0.52)分、(1.63±0.71)分,两组的腕关节DASH评分分别为(15.42±6.31)分、(18.03±7.64)分,均较术前明显改善,差异有统计学意义(P均<0.05);但腕关节镜组治疗后改善不明显.联合治疗组治疗后的NRS疼痛评分最低,腕关节镜组最高,三组间得分进行两两比较,差异均有统计学意义(均P<0.05).联合治疗组、尺骨短缩组治疗后的腕关节DASH评分差异并无统计学意义,但均优于腕关节镜组,差异均有统计学意义(均P<0.05).结论 尺骨短缩术联合腕关节镜技术对于桡骨远端骨折后畸形愈合造成的疼痛及功能障碍的改善具有积极的临床意义.     

Ulnar shortening osteotomy with a new sliding-hole plate

Ulnar shortening osteotomy represents a common procedure for surgical treatment of the ulnar impaction syndrome but is still associated with complications like malrotation, angulation, or malunion because of incomplete closure of the osteotomy gap. Therefore, the authors developed a special 7-hole compression plate that allows fixation of the ulna before the osteotomy is carried out to prevent rotation. With this plate, a shortening of up to 10 mm is possible and the compression holes allow closure of the osteotomy gap. The plate has been used in 23 ulnar shortening cases at their center with good results. The authors describe the technique and report their results of ulnar shortening with this device.     

Comminuted Monteggia fracture-dislocation--a technique for restoration of ulnar length: case reports

A technique to aid the reconstruction of the ulna in case of comminuted Monteggia fracture-dislocation is presented. This involves reducing the proximal radioulnar joint and temporarily transfixing the radial head to the ulna by 1 or 2 Kirschner (K) wires to establish the ulnar length. Once ulnar length has been defined, reconstruction of the comminuted ulna fracture is simplified. The radioulnar K-wires are then removed and the radioulnohumeral joint is tested for stability. This technique has been used in 6 cases of type-1 Monteggia fracture-dislocation with no subsequent malunion of the ulnar fracture or redislocation' of the radial head. After an average of 13 months follow-up, all patients had nearly full range of motion of the elbow joint.     

Intra-articular pressure as a factor in initiating ulnar drift

To determine the possible relevance of intra-articular pressure in the production of ulnar drift, metacarpophalangeal joints of fresh cadaver specimens were injected with water to increase the intra-articular pressure. Of the thirty-two joints tested, ulnar deviation was produced in twenty-three, flexion in twenty-four, and simultaneous ulnar deviation and flexion (ulnar drift) in nineteen. In two or three instances, the displacement was in extension or radial deviation. These results suggest that elevated intra-articular pressure may be a factor in the initiation of ulnar drift in patients with rheumatoid arthritis.     

Simultaneous radial closing wedge and ulnar shortening osteotomy for distal radius malunion

Closing wedge osteotomies are an attractive treatment option for distal radius malunion in patients with osteopenia. It does not require a separate-site bone graft, result-ing in decreased morbidity. However, this procedure has always been performed in combination with ulnar head resection to accommodate closure of corrective osteotomy and to address the issue of ulnocarpal abutment. Because ulnar shortening osteotomy is more physiological solution, it seemed advantageous to us to combine radial closing wedge osteotomy and ulnar shortening osteotomy. In this article, we present in detail our technique for treating patients with distal radius malunion. The patients are potentially osteopenic such as women aged over 45 years and are active at home, work, and/or recreation but are not involved in heavy physical work. Through volar approach an appropriate bone wedge is removed from the distal radius. A small volar T-plate is used to secure the osteotomized bone fragments. The aim of the radial osteotomy is to correct the dorsal angulation in the sagittal plane within a normal range of 1 degree to 2 degrees with reference to that of opposite wrist. Ulnar shortening osteotomy is performed by using transverse osteotomy and compression plating technique with an AO compression device. The ulnar variance is adjusted to neutral. Although the technique presented requires the surgeons to use careful plate and screw technique, early results have been encouraging, and patients with osteopenia can be treated successfully. Decreased grip strength which may be provoked by shorting of the forearm is acceptable.     

Pisotriquetral arthrosis after triquetral malunion: a case report

We report a patient with chronic ulnar palmar wrist pain caused by malunion after isolated fracture of the triquetrum. Intra-articular malunion of the triquetrum body resulted in posttraumatic pisotriquetral arthrosis. The diagnosis was made by magnetic resonance imaging, computed tomography, bone scintigraphy, and wrist arthroscopy 5 months after the injury. The patient's symptoms were relieved by excision of the pisiform.     

Wrist deformities after fracture

Wrist deformities can occur after fracture because of malunion of the fracture or injury to the growth plate leading to imbalance of growth. Prevention of malunion is paramount by early recognition with proper reduction and casting or fixation with casting. If a mal-union occurs, an osteotomy may be necessary if anticipated growth will not correct the deformity. Injury of the growth plate may lead to wrist deformity in two ways: angular growth or growth arrest. Angular growth deformities are corrected most commonly by osteotomy. Growth arrest of the radius or the ulna leads to an ulnar-positive or an ulnar-negative variance at the wrist. If the ulnar variance is symptomatic, treatment is centered on achieving a level joint. Options for joint leveling procedures include epiphysiodesis or physeal stapling of the longer bone, lengthening osteotomy of the shorter bone, or shortening osteotomy of the longer bone.     

Three-dimensional analysis of the ligamentous attachments of the first carpometacarpal joint

PURPOSE: To show the ligamentous locations and attachments of the first carpometacarpal (CMC) joint on a 3-dimensional (3-D) surface model. METHODS: Ten fresh-frozen cadaver wrists were used to dissect and identify the first CMC ligaments. Their ligamentous attachments and whole bone surfaces were digitized 3-dimensionally and their areas were calculated. The attachments of each ligament were represented in a model combining 3-D computed tomography surfaces overlaid by a digitized 3-D surface and also were shown visually by a specific color on 3-D bone images. The superimposed outlines of the ligamentous attachments on both the radial and ulnar base of the first metacarpal (MC) also are described. RESULTS: Seven ligaments of the first CMC joint were identified: the dorsoradial ligament, the posterior oblique ligament, the superficial anterior oblique ligament, the deep anterior oblique ligament, the ulnar collateral ligament, the dorsal first MC ulnar base-second MC radial base intermetacarpal ligament, and the volar first MC ulnar base-second MC radial base intermetacarpal ligament. The detailed locations and areas of the ligamentous attachments of the first CMC joint were determined. The average locations of the centroid of the ligamentous attachments of the ulnar collateral and the dorsoradial ligaments were located ulnovolar and dorsoradial on the first MC base, respectively. CONCLUSIONS: The anatomic 3-D attachment sites of the first CMC ligaments were shown qualitatively and their areas were quantified. The results of this study improve the knowledge and understanding of the normal anatomy and its impact on the mechanics of the first CMC joint. This should help in making an accurate assessment of radiographic images and treating injuries and degenerative changes in the first CMC joint by ligament reconstruction, repair, and arthroscopy.     

The effects of ulnar axial malalignment on supination and pronation

BACKGROUND: Forearm fractures are common injuries in both adults and children. Despite efforts to obtain anatomical alignment, axial rotational malunions occur, resulting in a decreased range of motion and a poor appearance. The objective of this study was to quantify loss of forearm rotation after simulation of ulnar malunions in supination and pronation. METHODS: Six fresh-frozen cadaveric upper extremities (mean age at the time of death, 79.4+/-2.8 years) were used to quantify loss of forearm rotation after simulation of axial rotational malunions of the ulna. First, maximum forearm rotation in supination and pronation was measured at torques of 6.8, 13.6, and 20.4 kilograms-centimeter applied with use of a custom jig. Following a midshaft ulnar osteotomy, a custom adjustable internal fixation plate was used to simulate axial rotational malunions of the ulna of 0, 15, 30, and 45 degrees in both directions. Measurements in supination and pronation were then repeated at the prespecified torques. Analysis of variance, with a p value of 0.05, was used for statistical analysis. RESULTS: In all instances, a decrease in forearm rotation after simulation of the ulnar rotational malunion was accompanied by an increase in rotation in the opposite direction. Supination and pronation were significantly influenced, whereas the total arc of rotation was not affected by ulnar rotational malunion. At a torque of 20.4 kilograms-centimeter, pronation malunions of 15, 30, and 45 degrees resulted in a mean loss of supination (and standard error of the mean) of 5+/-1, 11+/-1, and 20+/-1 degrees, respectively, and supination malunions of 15, 30, and 45 degrees resulted in a mean loss of pronation of 4+/-1, 10+/-2, and 18+/-4 degrees, respectively. The ratio of the simulated rotational malunion to the loss of motion was larger than one. CONCLUSIONS: Ulnar rotational malunions do not lead to a significant change in the total arc of forearm rotation. Instead, loss of motion in one direction is accompanied by increased motion in the opposite direction. Even with a 45-degree ulnar rotational malunion, forearm rotation decreases no more than 20 degrees.