Herbert Classification Research Articles

Scaphoid fracture epidemiology

The current available literature related to scaphoid fracture epidemiology is inconsistent. The aim of this study was to describe the epidemiology of true scaphoid fractures in a defined adult population. Using a prospective database, we identified all patients who sustained a radiographically confirmed acute fracture of the scaphoid over a 1-year period. Age, gender, mechanism of injury, the Herbert fracture classification, and associated injuries were recorded and analyzed. There were 151 scaphoid fractures diagnosed giving an annual incidence of 29 per 100,000 (95% confidence interval, 25–34). The median age of males was significantly younger when compared with females (p = 0.002), with a male (n = 105) predominance seen (p 0.001). Low-energy falls from a standing height were most common (40.4%), but with males being significantly more likely to sustain their fracture after a high-energy injury (p 0.001). The most common fracture was Herbert classification B2 (n =55, 36.4%), with unstable fractures more common in younger patients (p = 0.025) following a high-energy injury (p = 0.042). We have reported the epidemiology of true scaphoid fractures, with young males at risk of sustaining a fracture. Knowledge of the true incidence of scaphoid fractures and an understanding of the demographic risk factors are essential when assessing the suspected scaphoid fracture, particularly when considering further imaging modalities.

Optimal Fixation of Acute Scaphoid Fractures: Finite Element Analysis

The hypothesis of this study was that more stable fixation of acute scaphoid fractures may be achieved by a screw placed perpendicular to the fracture plane than along the long axis of the scaphoid, as previously suggested. We examined this assumption on different fracture patterns using a finite element analysis model. A computed tomography scan of an intact scaphoid of a young man provided the data set for all fracture models. We used semiautomatic segmentation to create 3-dimensional computer models of the 3 simple fracture configurations: oblique, transverse waist, and proximal fractures, according to the Herbert classification. Each fracture type was analyzed, using finite elements, for its biomechanical response to 2 types of virtual fixation: a screw placed either perpendicular to the fracture plane or centrally along the long axis of the scaphoid. We measured motion at the fracture plane (in millimeters) and strain in the screw threads (in millipascals). Considerably less motion was measured at the fracture plane with the perpendicular screw compared with the long axis screw, especially in the oblique-type fractures: (1) Herbert-type B1 oblique fracture mean motion of 0.05 mm (+/-0.03) for the perpendicular screw versus 0.28 mm (+/-0.05) for the long axis screw; (2) B2 transverse waist fracture mean motion of 0.06 mm (+/-0.03) for the perpendicular screw versus 0.18 mm (+/-0.06) for the long axis screw; and (3) B3 proximal fracture mean motion of 0.07 mm (+/-0.01) for the perpendicular screw versus 0.28 mm (+/-0.011) for the long axis screw. Higher strains were measured on the screw placed perpendicular to the fracture. According to this model, higher fixation stability is achieved when the scaphoid is fixated perpendicular to the fracture. In transverse waist fractures, a centrally placed screw will also be perpendicular to the fracture, which explains the results of previous models.

Percutaneous fixation of selected scaphoid fractures by dorsal approach

The aim of our study was to evaluate clinical, radiological and functional outcomes of selected cases of percutaneous fixation of scaphoid fractures via a dorsal approach. Percutaneous fixation by dorsal approach was done in 32 patients (mean age 32.2 years) involving both fresh and late scaphoid fracture presentations (mean 17 days). Fourteen cases of B1 type, ten cases of B2 and eight cases of C type (Herbert's classification) were treated. The patients were prospectively followed up clinically and radiologically for a minimum follow-up of 14 months (mean 16 months), and functional outcome and complications were assessed. All fractures united over an average of nine weeks. There was no avascular necrosis or screw cutout with preservation of wrist movement and grip strength. There were no injuries to any at risk anatomical structures. Percutaneous fixation of scaphoid fractures through dorsal approach gives good clinical and functional outcome in acute and chronic scaphoid fractures of B1, B2 and C types (Herbert's classification).

Rupture du tendon du fléchisseur radial du carpe après ostéosynthèse percutanée d’une fracture de scaphoïde. À propos d’un cas

We present a rare complication of percutaneous osteosynthesis of a scaphoid fracture. A 19-year-old professional handballer presented with a fracture of the scaphoid classified B2 according to the Herbert classification: the fracture was fixed with a percutaneous screw. The fracture was united by six weeks despite resumption of training eight days postoperatively. Subsequently, the patient presented with pain over the flexor carpi radialis (FCR) tendon together with reduction of wrist flexion strength suggested an FCR tendonitis. A CT scan with injection eliminated the diagnosis of non-union and showed protrusion of the distal end of the screw. After the failure of conservative treatment (corticosteroid injection), removal of the screw and synovectomy of the FCR were scheduled. During the procedure, attrition of the FCR tendon with scar tissue and metal inclusions in its fibres were observed. A visual examination of the screw's distal end showed a distortion of its hexagonal outline due to hammering, leading to metal projection likely to have caused the FCR tendon's attrition. We recommend the systematic burying of these canulated screws as well as changing any screw damaged during its insertion.

Minimal Invasive Screw Fixation and Early Mobilization of Acute Scaphoid Fractures in the Middle Third

Fractures of the scaphoid are relatively common injuries. Differentiation between stable and unstable fractures (Herbert classification) cannot always be made with conventional radiographs and should be additionally evaluated by computed tomographic scan. Under most circumstances, minimal invasive surgery with cannulated screws is currently the treatment of choice. Cast immobilization is not necessary. This article describes the technique of fracture fixation in the middle third of the scaphoid from a palmar approach and early functional outcomes. The outcome assessment included measurement of active range of motion as well as grip strength and the Disability of the Arm, Shoulder and Hand questionnaire as a measurement of activities of daily living. Fifty-four patients with acute scaphoid fractures were treated with minimal invasive screw fixation between April 2001 and January 2005. All patients in this retrospective study received a preoperative computed tomographic scan before surgery. Bony consolidation was found in 52 cases after 6 weeks; 2 patients required reosteosyntheses. The results demonstrate that minimal invasive screw fixation leads to satisfying functional outcomes within a few weeks.

Kahnbeinfrakturen - wann operativ, wann konservativ? CT-basierte Klassifikation

Traditionally acute scaphoid fractures were treated by immobilization. As a consequence we have to deal with a high number of scaphoid non-unions or SNAC wrists. A study of 30 patients with scaphoid non-union showed that only 30% (9 patients) have not seen a doctor, while the majority of the patients (70%, 21 patients) were treated by a physician after trauma. In 15 (71.4%) of these 21 patients a missed diagnosis and in 6 (28.6%) a failed conservative treatment of the scaphoid fracture were the reasons for scaphoid non-union. Therefore, improvements in the diagnosis and therapy of scaphoid fractures are urgently needed. Herbert's classification of scaphoid fractures provides the underlying rationale for treatment according to the fracture type seen on X-ray. Differentiation between stable and unstable fractures sometimes is difficult from conventional X-rays. In these cases we recommend a CT bone scan in the long axis of the scaphoid. According to the CT scan we modified Herbert's classification: undisplaced waist fractures are classified as stable and can be treated conservatively or can be stabilized percutaneously using minimally invasive procedures. Comminuted or displaced fractures are classified as unstable and need operative treatment because of the increased risk of scaphoid non-union after plaster immobilization. Fractures of the proximal pole of the scaphoid should be treated operatively by internal fixation, even if they are not displaced, because of the reduced perfusion. We recommend a CT scan of the scaphoid, if there is any doubt about the diagnosis or the stability of the scaphoid fracture. In any case, a CT scan has to be ordered to justify a conservative treatment.

Minimal invasive percutaneous Herbert screw fixation in acute unstable scaphoid fracture.

The purpose of this study is to document the percutaneous Herbert screw fixation technique with free-hand method to stabilise acute unstable scaphoid fractures and evaluated the clinical results. Thirteen patients with less than 14 day-old fractures were fixed by percutaneous Herbert screw and reviewed retrospectively for a minimum of 24 months (average, 37 months). All were men with an average age of 22 years. According to Herbert's classification, all fractures were classified as of the acute unstable (B2). Fracture union was achieved in all cases at a mean of 9.2 weeks (eight to 12 weeks). Return to work or school ranged from one day to three weeks according to their occupation. This percutaneous fixation technique using Herbert screw is a reliable and effective alternative for acute scaphoid fractures, which enables the patient to use the hand earlier with high satisfaction and minimum complication.

Scaphoid fracture in the young athlete--therapeutic outcome of internal fixation using the Herbert screw.

A fractured scaphoid is a common disabling injury occurring in contact sports. This study was designed to evaluate the therapeutic outcome of Herbert screw fixation for scaphoid fracture in young athletes. Thirty athletes with 30 scaphoid fractures were treated. According to the Herbert classification, 10 were classified as acute fracture (group I), 6 as fibrous union (group II) and 14 as pseudoarthrosis (group III). Twenty scaphoid non-unions were due to missed diagnosis or unsuccessful immobilisation. Bony union was evident at an average of 9.2, 8.0 and 11.9 weeks postoperatively in groups I, II and III, respectively, and times for returning to sports were 10.7, 14.0 and 22.9 weeks. The clinical outcome assessed using the Mayo wrist score was excellent in groups I (97.5 points) and II (93.3) and good in group III (85.4). Early definitive diagnosis and treatment can allow early return to sports in young athletes. The Herbert screw technique produces an excellent clinical result for scaphoid fracture.

Internal fixation of scaphoid non-union: a comparative study of three methods

In this study we compared the results of three methods of fixation for scaphoid non-union. The implants used were the AO 2 mm mini-fragment screw, the Herbert screw and the Kirschner (K) wires. Between 1990 and 1999, 132 patients underwent surgery for scaphoid fractures. We used the modified Filan and Herbert classification. Patients with acute fractures and patients requiring vascularised bone grafts were excluded. Twenty-six non-unions were fixed with an AO mini-fragment screw, 58 with a Herbert screw, and nine with K-wires. Radiological union was achieved in 85% of cases using the AO screw, 77% using the Herbert screw and 55% using the K-wire fixation. Statistically there was no significant difference between the AO and Herbert screw groups in terms of rate and speed of radiological union. The mechanical strength of the implant and the compression achieved did not seem to influence the union rate and speed. The type of bone graft (iliac crest or distal radius) did not significantly affect the union rates. Finally, K-wire fixation, either as a primary method or as a salvage procedure, produced inferior results and required prolonged immobilisation in plaster.

Management of proximal scaphoid bone pseudarthroses and fractures with the mini-Herbert screw via a dorsal approach

32 patients, aged 16 to 49 years, were treated by osteosynthesis using the Herbert mini screw. The indications were five fractures (type B3, Herbert classification), two delayed unions (type C) and 25 nonunions (type D1 to D3, Filan and Herbert classification). Six patients received no bone grafts, 19 received cancellous bone graft from the radius. An interpositional iliac crest bone graft was used in four, and a vascularized bone graft from the distal radius in three cases respectively. The average postoperative immobilisation in a forearm splint was nine weeks. 26 patients could be recruited for clinical follow-up at an average of 14.5 months. The radiological results were assessed in 30 cases (94%). Bony consolidation was achieved in 26 cases (100% of the fractures, 84% of the nonunions). In three cases a loosening of the screw, and in three further cases a dislocation into the radiocarpal joint were observed. A humpback deformity was present in four cases. Three patients showed a persisting nonunion, one patient a fibrous union. Early degenerative changes of the radiocarpal joint were observed in six cases. The clinical follow up examination showed an average grip strength of 91% (JAMAR II), 94% for the three finger, and 95% for the pinch grip compared to the contralateral side. The mean postoperative pain score on the visual analog scale was one for resting conditions, eleven for motion and 33 under stress. The range of motion was 79% of the opposite side for extension/flexion and 83% for radial/ulnar deviation. The average DASH-score reached 15 points. The Herbert mini screw has proven to be a reliable implant for reconstruction of proximal pole fractures and nonunions of the scaphoid.

Scaphoid fractures--diagnosis, classification and therapy

Herbert's classification of scaphoid fractures provides the underlying rationale for treatment according to the fracture type. A CT bone scan in the long axis of the scaphoid is the best means of differentiating between stable and unstable fractures. This is difficult from conventional X-rays due to the particular three-dimensional anatomy of the scaphoid. To avoid long-term plaster immobilization and to diminish the risk of a nonunion, unstable fractures of type B should be fixed operatively. With headless screws such as the Herbert screw, which are now available in a cannulated shape, the majority of scaphoid fractures of type B1 and B2 can be stabilized using minimally invasive procedures. Severely displaced fractures require the classical open palmar approach. Proximal pole fractures (B3) are best managed from the dorsal approach, using the Mini-Herbert screw. Stable fractures of type A2 can be treated conservatively in a below-elbow cast or, alternatively, stabilized percutaneously, which allows early mobilization.