Ulnar Impaction Research Articles

AN ANALYSIS OF CAUSES AND TREATMENT OUTCOME OF CHRONIC WRIST PAIN AFTER DISTAL RADIAL FRACTURES

Healed distal radial fractures are frequently complicated by chronic wrist pain which is multifactorial and can be debilitating. An accurate delineation of the pathoanatomy is the key for successful treatment. This study reviewed 22 patients who had surgical treatment between 1997 and 2001 for chronic wrist pain after distal radial fracture. Four patterns of pathoanatomy were identified: (1) ulnar impaction caused by radial malunion and shortening; (2) ulnar styloid non-union; (3) triangular fibrocartilage complex (TFCC) tears with or without distal radioulnar joint (DRUJ) instability; and (4) intercarpal ligament injuries and chondral lesions. Surgical treatment directed towards identified abnormalities gave satisfactory outcome. At six months after surgery the mean functional score improved 36%, mean pain score decreased 50%, mean grip strength improved 25%, and 64% of patients returned to work.

Factors Affecting Results of Ulnar Shortening for Ulnar Impaction Syndrome

Although ulnar shortening osteotomy is the most frequently performed operation for ulnar impaction syndrome, little attention has been given to detect certain preoperative factors affecting clinical outcomes of this procedure. We asked whether preoperative factors influenced the postoperative score of ulnar shortening osteotomy combined with arthroscopic debridement of the triangular fibrocartilage complex. We retrospectively reviewed 51 patients (53 wrists) with ulnar impaction syndrome treated with this procedure. There were 28 males and 23 females ranging in age from 14 to 67 years (mean, 37.5 years). The minimum followup was 12 months (mean, 26.3 months; range, 12-95 months). At last followup, we determined a modified Mayo wrist score for each patient. Preoperative factors affecting the clinical score were identified using multiple regression analysis. The clinical score ranged from 40 to 100 points (mean, 84.5 points). A long duration of symptoms and workers' compensation predicted worse clinical scores. We recommend considering these two factors when deciding whether to perform this procedure.

Acute Irreducible Distal Radioulnar Joint Dislocation

Dislocation of the distal radioulnar joint is a rare injury pattern. There is little in the English literature describing this injury and even less to direct treatment. We present the case of a patient with an irreducible dislocation of the distal radioulnar joint and discuss the pathoanatomy and operative treatment. In addition, we describe a novel radiographic and clinical finding of an ulnar impaction fracture, which we equate to the Hill-Sachs lesion noted in the humeral head following dislocation of the shoulder. Our patient was informed that data concerning the case would be submitted for publication. Aforty-year-old, right-hand dominant man presented to the emergency department immediately following a work-related injury. The patient had pain in the right wrist and lack of forearm rotation. In an attempt to catch a bag of cement that was thrown down from a truck, he struck the dorsum of the right wrist, which was supporting the 50-lb bag, against the right knee. The patient had no medical or surgical history that was relevant to the injury, nor had he sustained any previous injuries to the right forearm, wrist, or hand. On physical examination, the patient was only able to rotate the forearm between 30° and 80° with the right wrist held in a position of supination. There was loss of the dorsal prominence of the ulnar head, which was instead palpable on the volar side. The wrist was moderately swollen, tender to palpation, and painful with attempted pronation. The patient had no elbow or forearm pain. The skin and the neurovascular function, specifically including ulnar nerve function, were intact. Initial radiographs were made. The posteroanterior radiograph demonstrated an overlap of the radius and ulna at the distal radioulnar joint (Fig. 1-A), and a true lateral radiograph demonstrated volar displacement of the ulna with respect to …

Ulnar Shortening Osteotomy With a Premounted Sliding-Hole Plate

Ulnar shortening osteotomy represents a common procedure for various ulnar-sided wrist disorders but is still associated with complications like malrotation, angulation, or nonunion because of incomplete closure of the osteotomy gap. We describe the use of a newly developed palmarly placed sliding-hole dynamic compression plate that allows fixation of the ulna before the oblique osteotomy is carried out. We performed ulnar shortening osteotomy on 27 consecutive patients. The indication was ulnar impaction syndrome in 25 patients and symptomatic ulnar plus variance secondary to malunited distal radial fracture in 2 patients. The mean preoperative ulnar variance was +2.1 mm (range, +1 mm to +8 mm). All patients were evaluated before and after surgery and graded with the Disability of Arm-Shoulder-Hand (DASH) scoring system. All 27 osteotomies healed uneventfully over an average of 9.2 +/- 2.1 weeks. The mean postoperative ulnar variance was -2.1 mm (range, -3.1 mm to 0 mm). There were significant improvements in DASH score, pain, and grip strength at an average follow-up of 8.1 months. Six patients complained of plate irritation. Favorable results suggest that ulnar shortening osteotomy using an oblique osteotomy and a premounted sliding-hole compression plate avoids malrotation and angulation and is associated with satisfactory outcomes. This device does not require an assisting device, which minimizes the surgical exposure of the ulna. Palmar placement of the plate seems to reduce hardware irritation.

Chronic Wrist Pain - Rock Climbing

HISTROTY: 32yo female rock climber with a history of increasing left wrist pain. As a teen ager she had FOOSH injury to her right wrist while rock climbing and had xrays of both wrists demonstrating “bony abnormalities” needing a “cast.” Since, she has had pain while rock climbing. She never taped or braced. Currently, pain located dorsolateral/medial at the wrist and worse with hyperdorsiflexion such as pushing off and opening doors. No swelling or redness. No mechanical symptoms. No numbness or tingling. Elbow, shoulders and neck negative. Tried ibuprofen as needed but no physical therapy or bracing. History of patellar subluxation. PHYSICAL EXAMINATION: Inspection - no bony deformities, effusions or erythema. Symmetric active range of motion in all planes. Left wrist tender with terminal ulnar deviation. Palpation no nodules or masses but at the dorsal and volar ulnar aspects elicits some tenderness. Clicking at the ulnar aspect occurs with passive radial to ulnar deviation reported as uncomfortable. TFCC loading and table lift off test produces tenderness. Watson's scaphoid shift does not produce clicking or pain. Anatomic snuffbox palpation is negative. Tinel's is negative. Radial and ulnar pulses and sensation is intact and symmetric. Finger opposition strength is full. Hyper extension and abduction indicates laxity. DIFFERENTIAL DIAGNOSIS: TFCC tear. Carpal stress fracture. Scaphoid fracture non-union. Carpal instability. Distal radioulnar junction instability. TEST AND RESULTS: Plain film radiographs show lunotriquetral carpal coaltion. No scapholunate widening. MR Arthrography shows partial tears of ulnar attachment of TFCC without positive ulnar variance. Volar radioulnar ligament disruption with dorsal distal radioulnar joint subluxation. Lunotriquetral coalition, ulnar impaction. FINAL WORKING DIAGNOSIS: TFCC tear. DRUJ instability with dorsal subluxation. Lunotriquetral coalition. Ulnar impaction. Hyperlaxity. TREATMENT AND OUTCOMES: High dose NSAIDS and bracing. Cast immobilization deferred. Relative rest from rock climbing. At 4 months, intermittent pain with hyper dorsiflexion left greater than right. Refer to hand PT. At 6 months, improvement with relative rest but some symptoms with ADL's. Ortho Hand. Wrist taping for rock climbing.

Treatment of Ulnar Impaction Syndrome using Arthroscopy and Ulnar Shortening Osteotomy

Pur p ose: To retrospectively analyze the follow-up results of patients with ulnar impaction syndrome, who were treated with arthroscopic debridement, thermal shrinkage and a simultaneous ulnar shortening osteotomy. Mat e r ia ls and Met h ods: E leven wrists from ten patients with ulnar impaction syndrome, which were diagnosed by the clinical history, physical examination, radiological evaluation and arthroscopic findings, and were treated by arthroscopic debridement, thermal shrinkage and ulnar shortening osteotomy were enrolled in this study. The minimum duration of the follow-up was one year. The ulnar variance was measured using Kreder’s method, and the follow-up results were analyzed radiographically as well as clinically using the C hun and P almer wrist score. Resul ts : According to the wrist scoring system, seven wrists were fair and four poor preoperatively. However, after surgery, eight wrists were excellent and three good. The average wrist score increased from 62 preoperatively to 93 at the last follow-up. The mean ulnar variance decreased from +3.3 mm (+0.4-+6.4 mm) preoperatively to +0.1 mm ( －0.8-+1.3 mm) at the last follow-up. Radi ological union of the osteotomy site was achieved after an average of 12 weeks. There were no cases of nonunion or malunion.

Ulnar shortening osteotomy for ulnar ideopathic impaction syndrome

Twenty-eight patients were treated by ulnar shortening osteotomy for static or dynamic ulnar impaction syndrome. Ulnar variance was measured on a true anteroposterior radiograph. There were 25 wrists that were too long, two neutral, and one that was short. Bones were shortened by a mean of 3.5 mm. Mean follow-up time was 29 months (range 7-60), all with confirmed consolidation. At final follow-up mean grip strength had improved from 67% to 75%, mean Disabilities of the Arm, Shoulder, and Hand (DASH) score from 40 (range 12-83) to 26 (range 0-61) and mean range of movement from 80% (range 40%-100%) to 88% (range 50%-100%). Smoking, age at operation, type of osteotomy (transverse or oblique), dominance of hand, and sex did not influence consolidation or functionality. Special attention was paid to the anatomy of the distal radioulnar joint and the inclination of the sigmoid notch of the radius. There was no correlation between the anatomy and the functional outcome scores. Mean consolidation time (10 months) (range 2-32) and return to work were longer than in similar studies. Our findings confirm the usefulness of ulnar shortening osteotomy in the relief of ulnocarpal impingement symptoms.

The Effect of Radial Shortening on Wrist Joint Mechanics in Cadaver Specimens With Inherent Differences in Ulnar Variance

To assess load changes in the wrist and forearm resulting from surgically-induced radial shortening in wrists with inherent differences in ulnar variance. Eleven fresh cadaver upper extremities, 4 with ulnar-plus variance of 2 mm or greater and 7 with ulnar-minus variance of 2 mm or greater were used. The radius and ulna of each specimen were instrumented with load cells, a 15-mm segment of the radius was resected and replaced with aluminum blocks of various sizes, and the specimens were loaded with 143 N (32 lb) at 1-mm differences of radial length. The load distribution between the radius and ulna was measured. The load distribution in the specimens with an ulnar-plus variance averaged 69% through the radius and 31% through the ulna. In the wrists with ulnar-minus variance, the load distribution averaged 94% through the radius and 6% through the ulna. The mean force in the ulna increased and the mean force in the radius decreased with incremental shortening of the distal end of the radius. The mean force through the ulna in the ulnar-plus-variance group was always higher than that of the ulnar-minus-variance group. When compared not by the number of millimeters of radial shortening but by the adjusted ulnar variance, there was no difference between the ulnar-plus-variance and the ulnar-minus-variance groups. Wrists with ulnar-minus variance could accommodate radial shortening without as much increase in the ulna load as wrists with ulnar-plus variance. The clinical relevance is that a patient with an ulnar-minus variance may accommodate more radial shortening after a wrist fracture without developing an ulnar impaction syndrome than a patient with an ulnar-plus-variant wrist.

A rare differential diagnosis of acute forearm sepsis: Paget's disease leading to ulnar impaction syndrome

A rare differential diagnosis of acute forearm sepsis: Paget's disease leading to ulnar impaction syndrome

Ulnar Shortening Osteotomy in Idiopathic Ulnar Impaction Syndrome

Idiopathic ulnar impaction syndrome can be defined as a degenerative condition of the ulnar aspect of the wrist in patients with congenital or dynamic positive ulnar variance without a history of fracture or premature physeal arrest. The purpose of this study was to evaluate the clinical features of idiopathic ulnar impaction syndrome and the outcomes of ulnar shortening osteotomy for this group of patients. Thirty-one wrists in twenty-nine patients with idiopathic ulnar impaction syndrome were treated with an ulnar shortening osteotomy. Ulnar variance was measured on an anteroposterior radiograph of the wrist, and radioulnar distance was measured on a lateral radiograph, with the forearm in neutral rotation, to evaluate any displacement of the ulnar head from the distal aspect of the radius. All patients were followed clinically and radiographically for a mean of thirty-two months. An average preoperative ulnar variance of +4.6 mm (range, 2 to 7.5 mm) was reduced to an average of -0.7 mm (range, -4 to +1 mm) postoperatively. Preoperatively, the modified Gartland and Werley score was an average (and standard deviation) of 69.5 +/- 7.6, with twenty-four wrists rated poor and seven rated fair. Postoperatively, the score improved to an average of 92.5 +/- 8.0, with twenty-four wrists rated excellent; five, good; one, fair; and one, poor. Dorsal subluxation of the distal aspect of the ulna was found concomitantly in nine wrists, and it was found to be reduced by the shortening osteotomy. Seven patients had cystic changes in the carpal bones preoperatively, but these were not evident one to two years after the operation. Ulnar shortening osteotomy improved wrist function in patients with idiopathic ulnar impaction syndrome and reduced the subluxation of the distal radioulnar joint, which is commonly found in these patients. Degenerative cystic changes of the ulnar carpal bones appear to resolve following the shortening osteotomy.

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.

Early diagnosis of ulnar impaction syndrome

目的 探讨尺骨撞击综合征的特点及早期诊断方法并提出新的诊断标准.方法 对1998年12月～2004年12月治疗的123例腕尺侧疼痛患者进行仔细检查,采用顾玉东等提出的诊断标准,特别结合腕部MRI检查,确诊尺骨撞击综合征48例.总结尺骨撞击综合征的X线及MRI影像学特点,分析腕部临床症状与Chun和Palmer评分及影像学表现的关系.结果 本组33例患者存在尺骨阳性变异(68.8%),X线检查发现患者出现腕骨坏死比例为27.1%,其中以月骨坏死为主(64.7%);MRI检查均发现腕骨不同程度信号改变,腕部骨坏死均位于月骨尺侧部分的近端和三角骨腰部及底部;患者腕部临床症状与Chun和Palmer评分及影像学表现关系密切.结论 提高对尺骨撞击综合征的认识水平,以临床症状为基础,充分利用影像学检查,特别是MRI检查,可以明显提高该病征的早期诊断率。

Traitement arthroscopique des conflits ulnolunaires

The ulnar impaction syndrome is due to hyperpressure in the ulnocarpal joint. It occurs most frequently following distal radial fractures with shortening, but can also be secondary to a primitive length discrepancy between a short radius and a long ulna (positive ulnar variance). Symptoms and clinical findings, even though characteristic, are not specific. Standard X rays show a positive ulnar variance, and sometimes a hyperpressure cyst in the lunate. CT arthroscan and MRI studies demonstrate indirect signs of hyperpressure. If medical treatment fails to improve the condition, the choice surgical technique is arthroscopic, allowing debridement of the TFCC central tear, and shortening of the horizontal aspect of the ulnar head.

9.8 Treatment of stage II a and b ulnar impaction with arthroscopic TFCC disc excision and wafer distal ulna resection

9.8 Treatment of stage II a and b ulnar impaction with arthroscopic TFCC disc excision and wafer distal ulna resection

Ulnar Shortening Osteotomy in Idiopathic Ulnar Impaction Syndrome

Idiopathic ulnar impaction syndrome can be defined as a degenerative condition of the ulnar aspect of the wrist in patients with congenital or dynamic positive ulnar variance without a history of fracture or premature physeal arrest. The purpose of this study was to evaluate the clinical features of idiopathic ulnar impaction syndrome and the outcomes of ulnar shortening osteotomy for this group of patients. Thirty-one wrists in twenty-nine patients with idiopathic ulnar impaction syndrome were treated with an ulnar shortening osteotomy. Ulnar variance was measured on an anteroposterior radiograph of the wrist, and radioulnar distance was measured on a lateral radiograph, with the forearm in neutral rotation, to evaluate any displacement of the ulnar head from the distal aspect of the radius. All patients were followed clinically and radiographically for a mean of thirty-two months. An average preoperative ulnar variance of +4.6 mm (range, 2 to 7.5 mm) was reduced to an average of -0.7 mm (range, -4 to +1 mm) postoperatively. Preoperatively, the modified Gartland and Werley score was an average (and standard deviation) of 69.5 +/- 7.6, with twenty-four wrists rated poor and seven rated fair. Postoperatively, the score improved to an average of 92.5 +/- 8.0, with twenty-four wrists rated excellent; five, good; one, fair; and one, poor. Dorsal subluxation of the distal aspect of the ulna was found concomitantly in nine wrists, and it was found to be reduced by the shortening osteotomy. Seven patients had cystic changes in the carpal bones preoperatively, but these were not evident one to two years after the operation. Ulnar shortening osteotomy improved wrist function in patients with idiopathic ulnar impaction syndrome and reduced the subluxation of the distal radioulnar joint, which is commonly found in these patients. Degenerative cystic changes of the ulnar carpal bones appear to resolve following the shortening osteotomy.

Evaluation of Ulnar Styloid Length

General awareness of the ulnar styloid impaction syndrome is low and often is neglected. Radiographic evaluation of the ulnar styloid length generally includes an x-ray of the posteroanterior view. This study analyzed the effect of different radiographic views to assess the length of the ulnar styloid. The ulnar styloid-capitate ratio (SCR) expresses the relative length of the ulnar styloid, and we compare this ratio with the ulnar styloid process index (USPI). To evaluate the ulnar styloid and to analyze the effect of different radiographic views on measurement outcome, measurements were performed in 7 different radiographic positions of both wrists of 69 patients. To assess the relative size of the ulnar styloid and its impaction potential the USPI was calculated, re-evaluated, and compared with the SCR, in which the length of the ulnar styloid is divided by the length of the capitate bone. The mean ulnar styloid length in all standard posteroanterior radiographs is 4.4 +/- 1.2 mm. In our population the average USPI was 0.21 +/- 0.11 and the average SCR was 0.18 +/- 0.05. The SCR has a stronger correlation with the length of the ulnar styloid than the USPI. Furthermore this new ratio eliminates differences related to gender, whereas the USPI does not. To identify ulnar impaction potential we recommend using the USPI, but to compare ulnar styloid between patients we recommend using the SCR obtained from neutral posteroanterior radiographs. For white patients we suggest defining a long ulnar styloid as having an SCR greater than 0.18 +/- 0.05 and/or an overall styloid length greater than 6 mm.

Graft reconstruction of the interosseous membrane in conjunction with metallic radial head replacement: A cadaveric study

Longitudinal radioulnar dissociation (Essex-Lopresti injury) occurs when traumatic axial loading through the wrist disrupts the interosseous membrane (IOM) of the forearm and fractures the radial head. Proximal migration of the radius results in an ulnar-positive wrist, which can lead to painful ulnar-sided wrist degeneration and distal radioulnar joint instability. The purpose of this study was to measure the ability of an IOM reconstruction used in combination with a metal prosthetic radial head implant to reduce distal ulnar forces in a cadaveric model. The effects of varying the initial graft pretension on distal ulnar force were also studied. Twelve fresh frozen and thawed cadaveric forearms had a miniature load cell installed to record force in the distal ulna as the wrist was loaded axially to 134 N of compression force in neutral rotation. Intact forearms were tested first with the elbow in valgus and varus alignments. Loading tests were repeated after (1) insertion of a metal radial head implant that restored radius anatomic length, (2) excision of the IOM (with a radial head implant), and (3) reconstruction of the IOM using a palmaris longus tendon autograft (with a radial head implant). The implant then was removed and loading tests were repeated using 3 levels of initial graft pretension. Mean distal ulnar forces with an intact forearm were 23% of applied wrist force in the varus alignment and 12% in the valgus alignment. Mean force levels after insertion of the implant were 18% (varus) and 13% (valgus); these were not significantly different from corresponding values for the intact forearm. Mean force levels after section of the IOM were 30% (varus) and 14% (valgus); these were not significantly different from corresponding values for the intact forearm (varus and valgus) but the mean for varus was significantly greater than the corresponding value with an implant. After IOM reconstruction with a palmaris longus tendon tensioned to 22 N mean distal ulnar forces were 8% (varus) and 7% (valgus); these means were significantly less than the corresponding values for all prior test conditions. With the radial head removed increasing the level of graft pretension reduced significantly mean distal ulnar force. With the IOM resected insertion of a metal radial head implant alone did not reduce distal ulnar forces to intact forearm levels. When an IOM reconstruction was performed in combination with the implant mean distal ulnar force was reduced significantly to a level below that for the intact forearm. Applying pretension to the graft displaced the radius distally thereby making the wrist more ulnar negative and reducing distal ulnar force. Our results suggest that an IOM reconstruction used in combination with a metal radial head implant theoretically could help reduce distal ulnar impaction in an Essex-Lopresti injury.

Effects of wafer resection and hemiresection from the distal ulna on load-sharing at the wrist: A cadaveric study

Ulnar impaction syndrome is commonly the result of a naturally occurring ulnar-positive condition, distal radius fracture malunion, or collapse of a fractured radial head. The Feldon wafer procedure and the Bowers distal hemiresection procedure are designed to decrease force transmitted through the distal ulna. The purpose of this study was to measure the effects of these procedures on distal ulnar loading with varying degrees of ulnar positivity at the wrist. Using a specially designed miniature load cell distal ulnar force was measured in 20 fresh-frozen cadaveric forearms as the wrist was loaded axially to 134 N in neutral forearm rotation; tests were performed in valgus alignment with the elbow flexed to 90 degrees . Ulnar positivity (0 mm, +2 mm, +4 mm, and +6 mm) was created by incremental shortening of the distal radius using a sliding plate. The radial neck was sectioned transversely and the radial head fragment was fixed in its anatomic position using cemented metal prongs connected to a rigid bar; this allowed the radial head to be disconnected and tilted out of the loading pathway to simulate an excised radial head. Loading tests (with and without the radial head in place) were repeated after removal of a 3-mm wafer of bone beneath the triangular fibrocartilage complex, and again after a hemiresection of the distal ulna to the base of the ulnar styloid process. For each ulnar status condition (intact, wafer removal, hemiresection) the mean distal ulnar force generally increased as the wrist became more ulnar positive. Both wafer removal and hemiresection significantly decreased mean distal ulnar forces under all conditions of ulnar variance, with or without the radial head in place. With the radial head in place the mean distal ulnar forces (expressed as a percentage of applied wrist force) for the 0-mm condition were 16.9% (intact), 3.8% (wafer removal), and 3.5% (hemiresection); corresponding values for the +6-mm condition were 61.6% (intact), and 39.8% (wafer removal), 15.1% (hemiresection). With the radial head removed the mean distal ulnar forces for the 0-mm condition were 31.7% (intact), 4.6% (wafer removal), and 4.4% (hemiresection); corresponding values for the +6-mm condition were 96.4% (intact), 71.6%, (wafer removal), and 27.2% (hemiresection). The decrease of distal ulnar force resulting from hemiresection was significantly greater than that for wafer removal for all ulnar-positive conditions; force reductions were not significantly different between the 2 procedures with neutral ulnar variance. The results of the present study can help to offer a biomechanical basis for choosing between a Feldon wafer procedure and a Bowers hemiresection procedure in patients with ulnocarpal impaction syndrome. Both procedures produced equal decreases of distal ulnar force in the intact forearm. With an ulnar-positive wrist, the condition for which the procedure would be performed commonly, the hemiresection was more effective in decreasing force transmitted through the distal ulna.

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.

RECONSTRUCTION OF THE INTEROSSEOUS LIGAMENT OF THE FOREARM REDUCES LOAD ON THE RADIAL HEAD IN CADAVERS

Excision of the radial head after fracture may be complicated by longitudinal radio-ulnar instability (Essex-Lopresti lesion) if the forearm interosseous ligament has also been torn. In such cases proximal migration of the radius occurs, and ulnar impaction at the wrist and radiocapitellar contact at the elbow may impair function. Although metal radial head arthroplasties are now used for irreparable radial head fractures, the long-term clinical outcome may still be unsatisfactory because of excessive radiocapitellar load causing pain. Interosseous ligament reconstruction might improve outcome by restoring normal load transfer from the radius to ulna, but the biomechanical effect of reconstruction has not been reported. This study evaluated forearm load transfer following interosseous ligament reconstruction with an Achilles tendon allograft in a cadaveric model with the radial head intact. Interosseous ligament reconstruction reduced proximal radius loading by transferring force to the proximal ulna, but force transfer by the reconstruction was only half that by the intact ligament.