Aims

The aim of the Scaphoid Waist Internal Fixation for Fractures Trial (SWIFFT) was to determine the optimal treatment for adults with a bicortical undisplaced or minimally displaced fracture of the waist of the scaphoid, comparing early surgical fixation with initial cast immobilization, with immediate fixation being offered to patients with nonunion.

Aims

We quantitatively compared the 3D bone density distributions on CT scans performed on scaphoid waist fractures subacutely that went on to union or nonunion, and assessed whether 2D CT evaluations correlate with 3D bone density evaluations.

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

We hypothesised that the use of pulsed electromagnetic field (PEMF) bone growth stimulation in acute scaphoid fractures would significantly shorten the time to union and reduce the number of nonunions in a randomised, double-blind, placebo-controlled multicentre trial. A total of 102 patients (78 male, 24 female; mean age 35 years (18 to 77)) from five different medical centres with a unilateral undisplaced acute scaphoid fracture were randomly allocated to PEMF (n = 51) or placebo (n = 51) and assessed with regard to functional and radiological outcomes (multiplanar reconstructed CT scans) at 6, 9, 12, 24 and 52 weeks. The overall time to clinical and radiological healing did not differ significantly between the active PEMF group and the placebo group. We concluded that the addition of PEMF bone growth stimulation to the conservative treatment of acute scaphoid fractures does not accelerate bone healing.

Cite this article: Bone Joint J 2014; 96-B:1070–6.

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

Penetration of the dorsal screw when treating distal radius fractures with volar locking plates is an avoidable complication that causes lesions of the extensor tendon in between 2% and 6% of patients. We examined axial fluoroscopic views of the distal end of the radius to observe small amounts of dorsal screw penetration, and determined the ideal angle of inclination of the x-ray beam to the forearm when making this radiological view.

Six volar locking plates were inserted at the wrists of cadavers. The actual screw length was measured under direct vision through a dorsal approach to the distal radius. Axial radiographs were performed for different angles of inclination of the forearm at the elbow.

Comparing axial radiological measurements and real screw length, a statistically significant correlation could be demonstrated at an angle of inclination between 5° and 20°. The ideal angle of inclination required to minimise the risk of implanting over-long screws in a dorsal horizon radiological view is 15°.

Cite this article: Bone Joint J 2013;95-B:1101–5.

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

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

Follow-up radiographs are usually used as the reference standard for the diagnosis of suspected scaphoid fractures. However, these are prone to errors in interpretation. We performed a meta-analysis of 30 clinical studies on the diagnosis of suspected scaphoid fractures, in which agreement data between any of follow-up radiographs, bone scintigraphy, magnetic resonance (MR) imaging, or CT could be obtained, and combined this with latent class analysis to infer the accuracy of these tests on the diagnosis of suspected scaphoid fractures in the absence of an established standard. The estimated sensitivity and specificity were respectively 91.1% and 99.8% for follow-up radiographs, 97.8% and 93.5% for bone scintigraphy, 97.7% and 99.8% for MRI, and 85.2% and 99.5% for CT. The results were generally robust in multiple sensitivity analyses. There was large between-study heterogeneity for the sensitivity of follow-up radiographs and CT, and imprecision about their sensitivity estimates.

If we acknowledge the lack of a reference standard for diagnosing suspected scaphoid fractures, MRI is the most accurate test; follow-up radiographs and CT may be less sensitive, and bone scintigraphy less specific.

Using inaccurate quotations can propagate misleading information, which might affect the management of patients. The aim of this study was to determine the predictors of quotation inaccuracy in the peer-reviewed orthopaedic literature related to the scaphoid. We randomly selected 100 papers from ten orthopaedic journals. All references were retrieved in full text when available or otherwise excluded. Two observers independently rated all quotations from the selected papers by comparing the claims made by the authors with the data and expressed opinions of the reference source. A statistical analysis determined which article-related factors were predictors of quotation inaccuracy. The mean total inaccuracy rate of the 3840 verified quotes was 7.6%. There was no correlation between the rate of inaccuracy and the impact factor of the journal. Multivariable analysis identified the journal and the type of study (clinical, biomechanical, methodological, case report or review) as important predictors of the total quotation inaccuracy rate.

We concluded that inaccurate quotations in the peer-reviewed orthopaedic literature related to the scaphoid were common and slightly more so for certain journals and certain study types. Authors, reviewers and editorial staff play an important role in reducing this inaccuracy.

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

This study identified variables which influence the outcome of surgical management on 126 ununited scaphoid fractures managed by internal fixation and non-vascular bone grafting. The site of fracture was defined by a new method: the ratio of the length of the proximal fragment to the sum of the lengths of both fragments, calculated using specific views in the plain radiographs. Bone healing occurred in 71% (89) of cases. Only the site of nonunion (p = 1 × 10⁻⁶) and the delay to surgery (p = 0.001) remained significant on multivariate analysis. The effect of surgical delay on the probability of union increased as the fracture site moved proximally. A prediction model was produced by stepwise logistic regression analysis, enabling the surgeon to predict the success of surgery where the site of the nonunion and delay to surgery is known.

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

We describe a case of osteosarcoma of the scaphoid bone, which to our knowledge is only the second reported case of osteosarcoma in the carpus. A 38-year-old man complained of intense pain in the right wrist and had curettage and a bone graft for a lesion in the scaphoid. Histological examination showed this to be an osteosarcoma. Below-elbow amputation was performed and adjuvant chemotherapy given. There has been no evidence of recurrence or metastases at 33 months after amputation

1. Bony spurs resulting from erosion of the scaphoid bone and trapezium in rheumatoid arthritis can pierce the floor of the carpal tunnel and cause attrition rupture of flexor tendons–most often the flexor pollicis longus tendon. 2. It is difficult to show these spurs on conventional radiographs, but using a special tomographic technique we have been able to explore the floor of the carpal tunnel in three planes. Using this technique we have been able to guard the flexor pollicis longus against attrition rupture by early excision of a spur from the scaphoid bone. 3. Our findings support the recommendation of free division of the flexor retinaculum in rheumatoid arthritis. When doing this the surgeon should always look for a bony spur piercing the floor of the carpal tunnel

Cancellous inlay bone grafting for delayed union or non-union of the scaphoid bone gives good results in most cases (Table IV). The operation is easy, does not require radiological control and does not damage the dorsal arterial plexus. The indications for the operation are twofold: firstly for patients complaining of disabling symptoms in the wrist joint with an established pseudarthrosis of the scaphoid bone, with neither arthritic changes nor severe avascularity of the proximal fragment; and, secondly, for delayed union in recent fractures despite adequate immobilisation. Union may still occur if conservative treatment is continued further, but because this may take up to eighteen months (during which time most patients would be unable to work), operation is a reasonable alternative. In this series two scaphoid fractures united after operation with some collapse of the proximal fragment. This probably resulted from removal of too much bone (preliminary to inlaying the graft) from an already small fragment with a poor blood supply. The operation can be performed even in the presence of a small proximal fragment and gave a satisfactory result in two out of three such cases

1. Operative treatment of scaphoid pseudarthrosis by the Matti-Russe method is a reliable procedure which in our series has given ninety-seven cases of bony union in a total of 100 operations. 2. We do not hesitate to advise operation for this condition as soon as it is discovered, except in cases with severe secondary osteoarthritis. Equally good results have been reported by Murray (1946) from a series of 100 cases treated with cortical grafts from the tibia (blind method) and by Agner (1963) from a series of twenty-four patients treated by Bentzon's operation (interposition of a pedicled soft-tissue flap). 3. In our opinion, Russe's open operation has great technical advantages over Murray's blind method. 4. We have no experience of Bentzon's operation, which seems attractive on account of its technical simplicity and as not more than two weeks' immobilisation in plaster after operation are needed. 5. It would be interesting to see Agner's results confirmed from other sources. It is true that many scaphoid pseudarthroses remain symptomless for years, as London (1961) has pointed out, but many of them sooner or later cause pain, and we do not agree with London's opinion that a few weeks of immobilisation will usually make the wrist painless. 6. Although severe osteoarthritis is very slow to develop in wrists with pseudarthrosis of the scaphoid bone it cannot be denied that these wrists are constantly threatened with suddenly developing pain and by progressive deterioration of function. 7. Therefore, early repair of pseudarthrosis of the scaphoid bone is advisable; it can be expected to save many wrists from progressive loss of function and from final development of severe degenerative change