Bone bruising of the scaphoid is a common term reported, when MRI imaging is carried out for continued pain, within the anatomical snuff box. Is this significant? Our aim was to ascertain if bone bruising lead to continued symptoms, and resulted in delayed fracture detection- an occult fracture. This was a prospective study looking at 170 patients with scaphoid injuries. Of the 170 scaphoid injuries identified there were 120 scaphoid fractures seen on scaphoid view radiographs. The remaining 50 had no fracture on radiographs, however were clinically symptomatic and had MRI scaphoid imaging which demonstrated various grades of bone bruising. All were treated in a scaphoid plaster and re-examined at 8 weeks. There 4 were patients that remained symptomatic, MRI scan were performed which revealed 3 with resolving scaphoid bone bruising and 1 with a scaphoid fracture (p-value=0.05). Two further weeks of immobilisation resolved the symptoms of those 4 patients. Therefore occult scaphoid fractures demonstrating only bone bruising may take up to 8 weeks to declare itself as a fracture. Immobilisation in a scaphoid cast should be the mainstay of treatment for a minimum period of 8 weeks

Computer assisted surgery (CAS) is used in trauma surgery to reduce radiation and improve accuracy but it is time consuming. Some trials for navigation in small bone fractures were made, but they are still experimental. One major problem is the fixation of the dynamic reference base for navigation. We evaluated the benefit of a new image based guidance-system (Surgix®, Tel Aviv, Israel) for fracture treatment in scaphoid bones compared to the conventional method without navigation. The system consists of a workstation and surgical devices with embedded radio opaque markers. These markers as well as the object of interest must be on the same C-arm shot. If a tool is detected in an image by the attached workstation additional information such as trajectories are displayed in the original fluoroscopic image to serve the surgeon as aiming device. The system needs no referencing and no change of the workflow. For this study 20 synthetic hand models (Synbone®, Malans, Switzerland) were randomised in two groups. Aim of this study was a central guide-wire placement in the scaphoid bone, which was blindly measured by using postoperative CT-scans. Significant distinctions related to the duration of surgery, emission of radiation, radiation dose, and trials of guide-wire positioning were observed. By using the system the surgery duration was with 50 % shortened (p = 0.0054) compared to the conventional group. One reason might be the significant reduction of trials to achieve a central guide-wire placement in the bone (p = 0.0032). Consequently the radiation exposure for the surgeon and the patient could be shortened by reduction of radiation emission (p = 0.0014) and radiation dose (p = 0.0019). By using the imaged based guidance system a reduction of surgery duration, radiation exposure for the patient and the surgeon can be achieved. By a reduced number of trials for achieving a central guide-wire position the risk of weakening the bone structure can be minimised as well by using the system. The system seems helpful where navigation is not applicable up to now. The surgical workflow does not have to be chanced

The internal fixation of scaphoid bone fractures remains technically difficult due to the size of the bone and its three- dimensional shape. Early rigid fixation, e.g with a screw, has been shown to support good functional outcome. In terms of stability of the fracture, biomechanical studies have shown a superior result with central screw placement in the scaphoid in comparison with an eccentric position, which can lead to delayed or non-union. Image-based navigation could be helpful for these cases. The main limitation of reference-based navigation systems is their dependence on fixed markers like used in modern navigation systems. Therefore it is limited in treatment of small bone fractures. In former experimental studies 20 artificial hand specimens were randomised into two groups and blinded with polyurethane foam: 10 were treated conventionally and 10 were image guided. For trajectory guidance a reduction of duration of surgery, radiation exposure and perforation rate compared to the conventional technique could be found. Accuracy was not improved by the new technique. The purpose of this study was to identify the possible advantages of the new guidance technique in a clinical setting. In this prospective, non-randomised case series we tested the feasibility of the system into the accommodated surgical workflow. There was no control group. Three cases of scaphoid fractures were included. All of the patients were treated with a cannulated screw following K-wire placement via the percutaneous volar approach described. In addition, length measurements and screw sizes were determined using special features of the system. The performing surgeon and two attending assistant doctors (one assisting the surgical procedure, one handling the guidance system) had to rate the system following each procedure via a user questionnaire. They had to rate the system's integration in the workflow and its contribution to the success of the surgical procedure in percentages (0 %: totally unsuccessful; 100 %: perfect integration and excellent contribution). All of the clinical procedures were performed by the same surgeon. The surgeons rated the system's contribution and integration as very good (91 and 94 % of 100 %). No adverse event occurred. An average of 1.3 trials ± 0.6 (1; 2) was required to place the K-wire in the fractured scaphoid bone. The dose-area product was 19 cGycm2 ± 3 (16; 22). The mean incision until suture time was 36.7 min ± 5.7 (30; 40). For clinical cases, the system was integrated and rated as very helpful by users. The system is simple and can be easily integrated into the surgical workflow. Therefore it should be evaluated further in prospective clinical series

Scaphoid non-union results the typical humpback deformity, pronation of the distal fragment, and a bone defect in the non-union site with shortening. Bone grafting, whether open or arthroscopic, relies on fluoroscopic and direct visual assessment of reduction. However, because of the bone defect and irregular geometry, it is difficult to determine the precise width of the bone gap and restore the original bone length, and to correct interfragmentary rotation. Correction of alignment can be performed by computer-assisted planning and intraoperative guidance. The use of computer navigation in guiding reduction in scaphoid non-unions and displaced fractures has not been reported. Objective. We propose a method of anatomical reconstruction in scaphoid non-union by computer-assisted preoperative planning combined with intraoperative computer navigation. This could be done in conjunction with a minimally invasive, arthroscopic bone grafting technique. Methods. A model consisting of a scaphoid bone with a simulated fracture, a forearm model, and an attached patient tracker was used. 2 titanium K-wires were inserted into the distal scaphoid fragment. 3D images were acquired and matched to those from a computed tomography (CT) scan. In an image processing software, the non-union was reduced and pin tracts were planned into the proximal fragment. The K-wires were driven into the proximal fragment under computer navigation. Reduction was assessed by direct measurement. These steps were repeated in a cadaveric upper limb. A scaphoid fracture was created and a patient tracker was inserted into the radial shaft. A post-fixation CT was obtained to assess reduction. Results and Discussion. In both models, satisfactory alignment was obtained. There were minimal displacement and articular stepping, and scaphoid length was restored with less than 1mm discrepancy. This study demonstrated that an accurate reduction of the scaphoid in non-unions and displaced fractures can be accurately performed using computed navigation and computer-assisted planning. It is the first report on the use of computer navigation in correction of alignment in the wrist

The authors are not aware of any research comparing computed tomography (CT) and avascular necrosis (AVN) of the scaphoid bone. The primary aim of our study was to investigate the use of longitudinal CT in predicting AVN of the proximal pole of the scaphoid, and subsequent fracture nonunion following internal fixation. Thirty-two patients operated on by the senior author for scaphoid fracture were included. Preoperative CT scans were independently assessed for deformity, comminution, fracture position, proximal pole sclerosis, and bridging trabeculae. Intra-operative biopsy of the proximal pole was assessed independently by a blinded musculoskeletal histologist. AVN was determined by histology of a proximal pole biopsy, using the criteria described by Ficat. Post-operative CT scan was utilised to determine fracture union. Preoperative CT features which significantly correlated with AVN were, increased radiodensity of the proximal pole, the absence of any bridging trabeculae comminution, dorsal cortical angle, proximal fracture and age less than 20. Features predictive of subsequent nonunion were fractures of the proximal, increased radiodensity of the proximal pole, and AVN. Preoperative CT scan findings are significantly correlated with histologically confirmed AVN and fracture union. Preoperative longitudinal CT scan is of significant prognostic value and should be considered to assist in predicting outcome and assessing treatment options

50 consecutive cases of Scaphoid non-union were treated by open reduction and internal fixation. Average age of non-union was 2.8 yrs ranging fron 6 months to 6 years. Most common approach used was volar. Herbert screw was used to fix 48 non-unions while K wires were used in 2 cases. Bone graft was harvested from patient’s iliac crest and was used in nearly all cases. Wrist was immobilised in a plaster for an average duration of 12 weeks post operatively. All the cases were done by a single surgeon and the cases were recorded by an independent observer. The average follow up was 2 years ranging from 1 year to 6 years. Radiographic union was achieved in 45(80%) cases. Failure of union was seen in 10 cases out of which 5 were proximal pole fractures of which 2 went into avascular necrosis. Denervation of wrist, proximal row carpectomy and four corner fusion was used in 5 cases to salvage the wrist. This modest study carried out at a district general hospital of South East England suggests that scaphoid bone continues to be a challenge for general orthopaedic surgeon as some of these fractures are missed initially. Open reduction and internal fixation of Scaphoid non-union continues to give a predictable outcome

Background: Fracture of the scaphoid bone is the most common fracture of the carpus and frequently diagnosis is delayed. The unique anatomy & blood supply of the scaphoid itself predisposes to delayed union or non-union. The Synthes scaphoid screw is a cannulated headed screw, which provides superior compression compared with some other devices used to internally fix scaphoid non-unions. Aim: To conduct a retrospective study looking at union rate, time to union and complications and correlating the outcome of treatment against the delay between injury and surgery and location of the fracture within the bone. Methods: 36 patients with scaphoid non-union (30 waist & 6 proximal pole) treated by a single surgeon with the cannulated Synthes screw & corticocancellous bone graft were reviewed retrospectively. Results: We achieved 78% overall union rate. Those patients operated within 6 months of injury achieved 100% union rate. Of the patients with persistent non-union after surgery, half reported no pain and increased movement in the wrist. The failure rate was high in patients whose injury was more than 5 years old, and in proximal pole non-unions. Conclusion: Our study demonstrates that cannulated screw fixation with bone grafting has high success rate for delayed union of scaphoid waist fractures and scaphoid waist nonunions present for less than 5 years. Patients who present more than 5 years after injury or with proximal pole nonunions have a high chance of persistent nonunion, but can symptomatically improve

Background: Bone morphogenetic proteins (BMPs) induce new bone in patients with bone defects and at extraskeletal sites in animals. Standard treatment for symptomatic scaphoid non-unions is bone graft with or without internal fixation by a screw or wires. We tested the ability of human recombinant osteogenic protein-1 (OP-1, BMP-7) with compressed autologous or allogeneic bone graft to accelerate the healing of scaphoid non-union. Study Design: Randomized and controlled pilot study in 17 patients with a scaphoid nonunion. Methods: Patients were randomly assigned to one of three groups: (1) Autologous iliac graft (n=6), (2) Autologous iliac graft + OP-1 (n=6) and (3) Allogeneic iliac graft + OP-1 (n=5). Radiographic, scintigraphic and clinical outcomes were assessed throughout the follow-up period of 24 months. Results: OP-1 improved the performance of both autologous and allogeneic bone implants. Three dimensional helical CT scans and scintigraphy showed that the pre-existing sclerotic bone within proximal scaphoid poles was mainly replaced in OP-1 treated patients with well vascularized new bone. Addition of OP-1 to allogeneic bone implant equalized the clinical outcome with the autologous graft procedure and enabled circumventing the second donor graft harvest procedure resulting in less blood loss, shorter anesthesia and no pain at the donor side. Conclusion: This is the first evidence that a recombinant human BMP accelerates scaphoid bone non-union repair and resorption of sclerotic bone in this specific microenvironment. Clinical Relevance: OP-1 might be successfully used in healing of scaphoid non-union