Failure of a retinacular flap to prevent dorsal wrist pain after titanium Pi plate fixation of distal radius fractures

Patients with distal radius fractures that had been treated with a dorsal Pi plate and retinacular flap covering the transverse limb of the Pi plate were evaluated clinically and radiographically. Nine of 20 patients (45%) required plate removal for dorsal wrist pain. Three of the remaining 11 who retained the plate had dorsal tenderness over the wrist extensors. There were no differences evident between the 2 groups in plate size, position, or number of screws used. In addition there were no significant differences between the groups in either radial height or inclination. The palmar tilt did show a trend toward statistical significance: those patients who required plate removal had an average of 4.1 degrees of dorsal tilt, patients whose plate was not removed averaged 2.8 degrees of palmar tilt. Our results show that the retinacular flap covering the distal transverse limb of the Pi plate did not prevent the occurrence of dorsal wrist pain. Dorsal wrist pain remained a problem with dorsal plating of distal radius fractures.     

Anatomy of the anterior interosseous innervation of the pronator quadratus: evaluation of structures at risk in the single dorsal incision wrist denervation technique

PURPOSE: Patients with chronic wrist pain often are treated with wrist denervation, which typically involves transecting both the anterior interosseous nerve (AIN) and the posterior interosseous nerve. A single dorsal incision approach is an improvement over the more traditional multiple-incision technique. The purpose of our study was to describe the branches of the AIN to the pronator quadratus and evaluate the risk of denervation with the single dorsal incision technique. METHODS: Twelve fresh-frozen cadaver forearms were dissected. The branches of the AIN to the pronator quadratus were identified and the individual branch points were measured from the articular edge of the distal radius. Wrist denervation was then performed on each specimen through the single dorsal incision (as suggested by Berger). RESULTS: There were an average of 3 branches from the AIN to the pronator quadratus. All forearms had at least 1 branch to the pronator quadratus more proximal to the distal end of the dorsal skin incision; however, in only 2 of the forearms was the most proximal branch more than 2 cm proximal to the distal end of the dorsal skin incision. CONCLUSIONS: Wrist denervation through the recommended single dorsal incision poses a serious risk for completely denervating the pronator quadratus. Therefore the resection of the AIN must be performed close to the distal margin of the pronator quadratus.     

掌侧单切口联合背侧入路治疗桡骨远端粉碎性骨折25例报告

目的探讨经掌侧单切口联合背侧入路治疗桡骨远端粉碎性骨折的临床疗效。方法2010年6月-2012年10月对25例不稳定桡骨远端粉碎性骨折采用掌侧单切口、掌背侧联合人路放置掌侧锁定加压钢板固定。结果手术时间62—115min。平均84min。术中出血量10—80ml,平均22ml。术中桡动脉挫伤1例,术后B超检查未形成血管栓塞及血管瘤;伸肌腱粘连1例,经局部理疗及功能锻炼,术后5个月好转。25例随访6～28个月,平均14．1月。术后6～13周（平均8．3周）骨折愈合。按Gartland和Werley计分法评价,术后第24周腕关节功能优良率92．0％（23／25）;放射学评价按Lidstrom评分标准,桡骨关节面恢复优良率88．0％（22／25）。结论对桡骨远端粉碎性骨折,采用掌侧单切口、掌背侧联合入路的方法能清晰地同时显露桡骨远端掌背侧关节面,避免背侧辅助小切口,疗效满意。     

The effect of an extended flexor carpi radialis approach on blood flow to the distal radius: a cadaveric study

The effect of an extended flexor carpi radialis approach on the blood supply of the radius was examined in six (3 paired) fresh frozen cadaver limbs after injection with India ink and clearing using a modified Spalteholz technique. An extended flexor carpi radialis approach to the distal radius was made in the left limb in each of the three-paired limbs. The right limb served as a nonoperative control. Following perfusion of the arterial vasculature of each limb with India ink, serial transverse sections were cut and the intraosseous blood supply evaluated using a modified Spalteholz technique. Both controls and surgical specimens demonstrated complete cortical penetration from endosteal vessels in the proximal and midsections of the radius. In the distal radius, surgical specimens demonstrated reduced perfusion volarly, however there continued to be perfusion of ink through intact dorsal and ulnar metaphyseal perforating arteries. Persistent vascular perfusion to the distal radius remains through intact endosteal vessels and metaphyseal perforators of extensive surgical soft-tissue stripping.     

Radiocarpal fracture--dislocation

Radiocarpal fracture-dislocation was associated with fracture of the distal articular surface of the radius in five patients (six extremities). Closed manipulation resulted in satisfactory reduction of both the dorsal dislocation of the carpus on the distal radius and displaced articular fracture fragment(s) in two of four extremities. In four extremities, open reduction was necessary as the only means of satisfactorily managing this severe wrist injury. Direct visualization through a dorsolateral incision alone allows for maximal restoration of the often extensive bony injury of the dorsal articular surface of the radius. A volar incision is required for anatomic reduction of the carpus, and median reconstitution of the radiocarpal ligament nerve decompression. Functional results were generally satisfactory; however, radiographic degenerative changes appearing early portend traumatic arthritis as a sequela of this complex injury.     

T incision for exposure of the distal radius and wrist

A retrospective review of 66 T-shaped incisions for exposure of the dorsal distal radius and wrist was performed. The incision provided excellent exposure in all cases and no additional incisions were required. Cosmesis was considered acceptable by all patients. Complications occurred in 6% and were more likely in patients undergoing fixation of acute distal radius fractures using Kirschner wires which protruded through the skin flaps.     

The effects of dorsally angulated distal radius fractures on carpal kinematics

A cadaver model was used in a biomechanical study of dorsally angulated distal radius fractures to evaluate alterations in carpal kinematics. Distal radius fractures were simulated by dorsal closing-wedge osteotomy and fixed with a custom-designed external fixator. A magnetic tracking device measured the carpal bone motions in several positions of dorsal angulation from neutral tilt to 30 degrees dorsal tilt. Changes in carpal alignment showed different patterns between each specimen consisting of a spectrum from dorsal subluxation of the entire carpus to adaptive dorsal carpal instability (DISI deformity). Components of carpal bone motion were altered markedly at all positions of dorsal angulation of the distal radius. The severity of the DISI deformity and related carpal instability correlated well with the alterations of carpal kinematics during wrist flexion and extension, whereas dorsal subluxation alone had a poor relationship with changes in carpal kinematics. The amount of DISI deformity and the degree of dorsal angulation of the radius may be prognostic factors when considering whether to perform a corrective osteotomy of the distal radius.     

Distal Radius Fractures: Choice of Treatment Procedures

Summary BACKGROUND: Distal radius fractures are no longer injuries typical of elderly patients with osteoporosis. Driving at high speed and high-speed sports activities are responsible for causing such injuries in an increasing number of younger people. Although the kind of fracture suffered, bone density, and personal needs and requirements of patients demand an individualized treatment concept, a surgical approach for stabilization of the fracture is gaining wider recognition. METHODS: The current treatment regimens for distal radius fractures are reviewed. RESULTS: Good results can be achieved in certain specific forms of fracture by conservative treatment. The preconditions are that it is possible to perform a closed reduction of the fracture and that the limb can be kept in a plaster cast until bone healing has taken place. Furthermore, a conservative approach needs to be used in cases where surgery cannot be performed for a variety of reasons. Where surgery is performed, percutaneous methods are adequate if the fracture undergoes closed reduction, but a plaster cast cannot be applied because of metaphysial compression or injuries to the ligaments. Fixation with pins, concealed screws, and external fixation can all contribute to good healing results if the correct technique is used for the type of fracture treated. Open reduction and osteosynthesis with plates and screws combined with bone graft for defect filling is surgically quite demanding, but in patients exposed to manual stress, this approach is required for optimal reconstruction and rehabilitation. Depending on the fracture type, different approaches, such as the dorsal, palmar, or palmar with an additional dorsal incision, have to be used for plate placement. Stable osteosynthesis enables early functional rehabilitation. CONCLUSIONS: Even if it were possible to offer specific recommendations for treating different forms of distal radius fractures, factors that are decisive in the treatment concept are the general health, bone density, and the wishes of the patient. It is essential to take into consideration all these factors for a successful treatment of distal radius fractures.     

A method of defining palpable landmarks for the ligament-splitting dorsal wrist capsulotomy

PURPOSE: The concept of a ligament-splitting dorsal capsulotomy of the wrist has been defined and has been shown to have practical applications. Due to the abundance of peritendinous tissue, however, the ligaments are often difficult to visualize. This article presents a method of defining incision capsular lines based on reliably palpable landmarks. METHODS: The palpable landmarks include the sulcus between the scaphoid and trapezoid, the dorsal tubercle of the triquetrum, and the midpoint between Lister's tubercle and the dorsal rim of the sigmoid notch. These points identify the bisection lines of the dorsal intercarpal and dorsal radiocarpal ligaments. A radial-based capsulotomy can be easily elevated by incising the dorsal wrist joint capsule using these landmarks and then extending the incision along the dorsal rim of the distal radius to the radial styloid process. RESULTS: This method of defining capsular incision lines based on palpable landmarks was used on 253 consecutive dorsal wrist arthrotomies with excellent exposure, accurate splitting of the dorsal radiocarpal and intercarpal ligaments, and no complications. CONCLUSIONS: Using specific, palpable landmarks on the dorsal wrist, an accurate estimation of the locations and courses of the dorsal radiocarpal and intercarpal ligaments can be reliably made. Even when poorly visualized, these ligaments can be split longitudinally in a reliable fashion to create a standard, ligament-sparing dorsal capsulotomy.     

掌侧和背侧钢板内固定治疗背侧不稳定性桡骨远端骨折的病例对照研究

目的:探讨两种不同手术入路内固定方法对背侧不稳定性桡骨远端骨折的疗效。方法:收集2006年8月至2010年10月采用手术切开复位钢板内固定治疗,并获得随访的病例47例。男21例,女26例;年龄39～73岁。所有患者分为2组:采用掌侧入路掌侧钢板内固定(A组)32例,锁定钢板27例,普通"T"形钢板5例,其中4例联合应用背侧克氏针内固定;采用背侧钢板内固定(B组)15例,其中锁定钢板7例,普通"T"形钢板8例。术后从腕关节功能、X线评分及并发症等方面对掌侧和背侧钢板2种固定方法的疗效进行比较。结果:掌侧和背侧钢板固定术后1周与术前比较,掌倾角、尺偏角及桡骨茎突高度均明显改善;2组术后1周与术后半年比较,掌倾角、尺偏角及桡骨茎突高度均无明显丢失。术后A组正中神经牵拉伤1例,切口感染1例,肌腱粘连2例;B组切口红肿感染1例,肌腱粘连1例,拇长伸肌腱刺激3例;掌侧钢板内固定并发症的发生率低于背侧钢板内固定。腕关节功能评价:A组优17例,良11例,可3例,差1例;B组优8例,良4例,可2例,差1例;掌侧钢板内固定与背侧钢板内固定疗效无明显差异。结论:背侧移位的桡骨远端不稳定骨折,采用掌侧入路掌侧钢板内固定同样可以达到良好的复位效果,而肌腱损害等并发症较背侧钢板固定更少。     

Intraoperative evaluation of DRUJ instability through dorsal stress radiography in distal radius fractures

IntroductionCertain type of injury of the triangular fibrocartilage complex associated with distal radius fracture can result in distal radioulnar joint instability (DRUJ). Untreated DRUJ instability may lead to poor result in the treatment of acute distal radius fractures. The aim of this study was to evaluate DRUJ instability in distal radius fractures through dorsal stress radiography comparing the affected and unaffected wrists intraoperatively.Materials and methods49 patients with a distal radius fracture who were operatively treated with a volar locking plate were included. Dorsal stress radiography was used to evaluate both affected and unaffected wrists peri-operatively to detect DRUJ instability. Under general anesthesia, a dorsal stress test was performed on the unaffected wrist. Additionally, after fixation of the affected wrist, a dorsal stress test was performed. The ulnar translation ratio (UTR) was measured through the dorsal stress radiograph. Arthroscopic examination was performed on all affected wrists according to Palmer's and Atzei classification.ResultsThe UTR of the affected wrist and the TFCC injury Palmer-type IB tendency were positively correlated (odds ratio: 1.18, p-value: 0.002). Additionally, as the UTR difference between the affected and unaffected wrists enlarged, it revealed a significant DRUJ instability tendency due to Palmer-type IB TFCC injury (p-value: 0.000006, Wilcoxon rank-sum test).ConclusionsDorsal stress radiography is a reliable, simple procedure to evaluate DRUJ instability intraoperatively. UTR value from dorsal stress radiography could be useful for evaluating DRUJ instability associated with distal radius fracture.     

Vascular anatomy of the pronator quadratus muscle-bone flap: a justification for its use with a distally based blood supply

The vascular anatomy of the pronator quadratus muscle and distal radius was studied in 24 cadaveric forearms by dissection under magnification and india ink and latex injection studies. The anterior interosseous artery divides into a muscular branch and a dorsal branch 1 cm to 3.5 cm from the proximal margin of the pronator quadratus muscle, and on its deep surface. Injection studies showed a rich periosteal plexus contributed by the anterior interosseous artery. Retrograde injection through the dorsal branch also showed good perfusion of the distal radius that was confirmed microscopically on bone sections. A muscle-bone graft from the anteromedial cortex of distal radius with an intact anterior interosseous artery has mobility of less than 2 cm. After ligating and dividing the anterior interosseous artery, blood supply to the distal radius bone flap relies on a retrograde flow and the bone flap could then be mobilized distally up to 4 to 6 cm.     

Combined dorsal and volar plate fixation of complex fractures of the distal part of the radius

BACKGROUND: Fractures of the distal part of the radius that are associated with complex comminution of both the articular surface and the metaphysis (subgroup C3.2 according to the Comprehensive Classification of Fractures) are a challenge for surgeons using standard operative techniques. METHODS: Twenty-five patients with subgroup-C3.2 fractures that had been treated with combined dorsal and volar plate fixation were evaluated at an average of twenty-six months after the injury. Subsequent procedures included implant removal in twenty-one patients and reconstruction of a ruptured tendon in two patients. RESULTS: An average of 54 degrees of extension, 51 degrees of flexion, 79 degrees of pronation, and 74 degrees of supination were achieved. The grip strength in the involved limb was an average of 78% of that in the contralateral limb. The average radiographic measurements were 2 degrees of dorsal angulation, 21 degrees of ulnar inclination, 0.8 mm of positive ulnar variance, and 0.7 mm of articular incongruity. Seven patients had radiographic signs of arthrosis during the follow-up period. A good or excellent functional result was achieved for twenty-four patients (96%) according to the rating system of Gartland and Werley and for ten patients (40%) according to the more stringent modified system of Green and O'Brien. CONCLUSIONS: Combined dorsal and volar plate fixation of the distal part of the radius can achieve a stable, mobile wrist in patients with very complex fractures. The results are limited by the severity of the injury and may deteriorate with longer follow-up. A second operation for implant removal is common, and there is a small risk of tendon-related complications.     

AO C3型桡骨远端骨折固定方法研究的生物力学模型

目的设计一个C3型桡骨远端骨折尸骨模型并评估其有效性。方法设计并制作一个C3型桡骨远端骨折尸骨模型,并用其评估背侧钢板固定桡骨远端骨折的生物力学特性。结果在完整标本上100N纵向负荷仅使桡骨产生1～2mm弹性变,其中桡骨传递83.82%的负荷。在7具标本上成功制作C3型桡骨远端骨折模型,用背侧钢板固定骨折后,发现桡骨传递75.64%的负荷。结论本研究成功制作可重复性好的C3型桡骨远端骨折尸骨模型,生物力学测试提示在100N纵向负荷下,背侧钢板固定不能完全重建桡骨远端骨折的力学性能。     

Kinematic and torque-related effects of dorsally angulated distal radius fractures and the distal radial ulnar joint

PURPOSE: The purpose of this study was to examine the torque required to achieve a full range of motion of the distal radioulnar joint (DRUJ) as a result of increasing dorsal angulation from simulated fractures of the distal radius. Based on this study the accepted amount of dorsal angulation of the distal radius can be determined. METHODS: In 9 fresh cadaver limbs motion of the DRUJ was simulated by a custom motion and loading forearm device. The malunion model of the distal radius was controlled by a specially designed external fixation frame that provided control in 6 degrees of dorsal angulations (N, 0 degrees, 10 degrees, 20 degrees, 30 degrees, and 40 degrees ). The study included an intact and nonintact triangular fibrocartilage complex. RESULTS: This study showed that torque across the DRUJ was affected by the degree of simulated malunion of the distal radius. With more than 30 degrees dorsal angulation the torque across the DRUJ was increased in both muscle loading and unloading conditions. Although significance was not noted, with resistive loading this study showed torque changes with as little as 10 degrees malunion of the distal radius. CONCLUSIONS: We conclude that reduction of distal radius fractures to within 10 degrees of dorsal angulation is needed to allow patients to maintain full forearm and wrist rotation.     

锁定加压钢板在桡骨远端骨折中的应用

目的 探讨锁定加压钢板（locking compression plate，LCP）在桡骨远端骨折治疗中的应用效果。方法 对11例桡骨远端粉碎性骨折患者经掌侧或背侧切口进行切开复位、LCP内固定，其中3例给予自体骨移植，术后早期进行功能锻炼。结果 术后随访5～24个月，骨折愈合良好，根据改良McBride评分和纽约骨科医院腕关节评估标准：优8例，良2例，可1例，优良率达90．9％，疗效明显。结论 LCP内固定治疗桡骨远端粉碎性骨折临床疗效满意，尤其适合合并骨质疏松的老年病人。     

Irreducible dorsal distal radius fracture-dislocation with accompanying dorsal displacement of flexor tendons and median nerve: A rare type of injury

INTRODUCTION

High energy distal radius fractures may cause significant soft tissue injuries. Dorsal displacement of median nerve and flexor tendons to dorsal compartment between distal radioulnar joint was an unreported type of soft tissue injury.

PRESENTATION OF CASE

35-Year male admitted following fall from height diagnosed as closed distal radius fracture with dorsal displacement. The patient had no flexion and extension of all fingers with loss of sensation. Radial artery pulse was not palpable. Radiography and CT imaging revealed distal radius fracture with dorsal displacement with dorsal carpal dislocation. After failure of closed reduction, operative treatment was performed. At surgery, flexor tendons and median nerve was found to be placed at dorsal compartment. Reduction of the soft tissues was facilitated by distraction of distal radioulnar joint.

DISCUSSION

Dorsal displacement of volar structures as the result of fracture dislocation was found to be an unreported type of injury. Difficulty during reduction of dorsally displaced structures is an important feature of the case.

CONCLUSION

For severely displaced and deformed distal radial fractures and fracture dislocations, threshold for operative treatment should be kept low.     

A randomized prospective study on the treatment of intra-articular distal radius fractures: open reduction and internal fixation with dorsal plating versus mini open reduction, percutaneous fixation, and external fixation

PURPOSE: To compare 2 methods of surgical treatment for displaced intra-articular fractures of the distal radius: open reduction and internal fixation with dorsal plating (Pi Plate; Synthes, Paoli, PA) versus mini open reduction with percutaneous K-wire and external fixation. METHODS: Patients with AO type C intra-articular distal radius fractures were randomized into 2 groups: open reduction and internal fixation and dorsal plating or external fixation and K-wires and mini-open reduction. Patients over the age of 70 years with any associated soft-tissue or skeletal injury to the same limb and pre-existing wrist arthrosis or disability were excluded from the study. Objective, subjective, and radiographic outcomes were assessed at 2 weeks, 4 to 6 weeks, 10 to 12 weeks, 6 months, and 1- and 2-year intervals. The minimum follow-up period was 6 months; the average follow-up period was 18 months. The principal outcome analyzed was the Disabilities of the Arm, Shoulder, and Hand score. Secondary outcomes included grip strength, range of motion, surgical procedure time, complications, and radiographic parameters. The groups were equal with respect to age, gender, fracture subtype, and number of workers' compensation cases. RESULTS: No significant difference was found in the Disabilities of the Arm, Shoulder, and Hand scores, our primary outcome. The dorsal plate group, however, showed a higher complication rate when compared with the external fixator group. The plate group had significantly longer tourniquet times when compared with the external fixator group. The plate group also had higher levels of pain at 1 year when compared with the external fixator group; however, this equalized after hardware removal. The external fixator group showed an average grip strength of 97% compared with the normal side and 86% in the dorsal plate group. CONCLUSIONS: At midterm analysis the dorsal plate group showed a significantly higher complication rate compared with the external fixator group; therefore enrollment in the study was terminated. The dorsal plate group also showed statistically significant higher levels of pain, weaker grip strength, and longer surgical and tourniquet times. Based on these results we cannot recommend the use of dorsal plates in treating complex intra-articular fractures of the distal radius.     

Accuracy of the skyline view for detecting dorsal cortical penetration during volar distal radius fixation

Fractures of the distal radius are commonly treated using volar locking plates. Several complications have been associated with this procedure, including extensor tendon irritation and rupture. It has been suggested that prominence of screws past the dorsal cortex may contribute to this complication. This study aimed to determine the ability of the skyline view to demonstrate screws penetrating the dorsal cortex. A volar locking plate was applied to a synthetic forearm model. Lateral, oblique, and skyline views were obtained, with the distal screws both beneath and 1 mm beyond the dorsal cortex. The images were shown to orthopaedic trainees who were asked to decide if screws penetrated the dorsal cortex. Subjects were correct in 83% of cases using the skyline view compared with 77% (p = 0.05, lateral) and 50% (p < 0.01, oblique). This study demonstrates the skyline view of the distal radius could be a useful and accurate addition to routine intraoperative fluoroscopy views.