Scaphoid fractures and nonunions: diagnosis and treatment

Spontaneous Healing of a Scaphoid Nonunion Following an Ipsilateral Distal Radius Fracture: A Case Report

CASE

A 55-year-old professional flutist developed a scaphoid waist nonunion that did not receive initial treatment. Six months later, she sustained an ipsilateral distal radius fracture for which cast immobilization was applied as conservative treatment. This approach facilitated healing of the distal radius fracture and serendipitously led to spontaneous healing of the scaphoid nonunion.

CONCLUSION

This case illustrates an unusual healing response in a scaphoid nonunion, which typically requires surgical intervention. The spontaneous healing observed in this case following conservative treatment highlights the potential for nonsurgical approaches in managing similar cases.

Scaphoid Reconstruction Following Nonunion in Osteogenesis Imperfecta: A Case Report

CASE

An 11-year-old boy with osteogenesis imperfecta (OI) type 1 presented with a chronic scaphoid waist nonunion accompanied by cyst formation and dorsal intercalated segment instability. He had a history of treatment with bisphosphonate therapy and discontinued zoledronate 3 months before surgery. He underwent scaphoid reconstruction using nonvascularized, corticocancellous bone graft from the iliac crest and a buried headless compression screw. Within 12 weeks, imaging demonstrated union with bony remodeling and he resumed zoledronate.

CONCLUSION

Temporary discontinuation of bisphosphonate therapy may normalize bone healing and reduce the risk of bisphosphonate-related delayed union in scaphoid reconstruction for children with OI.

Radiological Diagnosis of Suspected Scaphoid Fractures in Children: A Systematic Review

Background: Children presenting with suspicion of a scaphoid fracture pose a diagnostic challenge. Several imaging modalities such as plain radiograph (XR), computed tomography (CT), and magnetic resonance imaging (MRI) have been previously described. Timely and accurate diagnosis is important to avoid overtreatment, and complications, and allow for an earlier return to activity. It is unclear which imaging modality is the most diagnostically accurate for detecting scaphoid fractures in this population. Methods: A systematic review was conducted in concordance with established guidelines to elucidate the diagnostic accuracy of various imaging modalities for detecting scaphoid fractures in children. A comprehensive literature search of electronic databases was developed by experienced librarians. All steps were performed independently by 2 reviewers. Results: Eight articles were included, all evaluating plain radiographs as the index test. One study evaluated CT. XR demonstrated sensitivity values ranging from 16% to 54%, with specificity of 71% to 100%. CT had 95% sensitivity with MRI as the reference standard. The included studies were limited by poor methodologic quality and heterogeneous patient populations. Conclusions: XR demonstrates a wide range of diagnostic accuracy in diagnosing scaphoid fractures in children. CT and MRI, while promising, are limited by a lack of evidence in children. More pediatric-specific prospective studies are required to guide the choice of diagnostic imaging in children with suspected scaphoid fractures.

Surgical Technique: "Perforate and Fill" Technique of Bone Grafting for Scaphoid Fracture Fixation

Purpose

We introduce the "Perforate and Fill" technique for bone grafting of scaphoid fracture with delayed union and nonunion, which preserves the cartilage shell and does not break open the fibrous nonunion. This article describes the technique and reports the experience in 11 scaphoid fractures.

Methods

The records of 11 patients whose scaphoid fractures were managed surgically with this bone grating technique from our institution from July 2017 to June 2024 were reviewed retrospectively. Patient and fracture factors, radiographic measurements of bone defect, postoperative films, and subjective and objective outcomes were considered.

Results

The radiographic union of the fracture ranges from 36 to 110 days (an average of 68 days). In the last follow-up review, the affected wrists were pain free in all cases, and they were able to resume their premorbid status of vocation and resumed all physical activities. In nine cases, their total wrist motion (including flexion, extension, radial, and ulnar deviation) measured 130° to 195° (an average of 172° and 93% of the opposite wrists). In these nine cases, their grip strengths measured 28-50 kg (an average of 31.5 kg and is 97% of the opposite hand).

Conclusions

In conclusion, in treatment of scaphoid fracture delayed union and nonunion, the "Perforate and Fill" technique of bone grafting is a good alternative to the conventional wedge grafting technique. The advantage of keeping the intact cohesive union of cartilage shell and a less-invasive approach may contribute to the success of the fracture union in our 11 cases using this technique.

Type of study/level of evidence

Therapeutic IV.

Documented Cannabis Use Is a Risk Factor for Nonunion After Nonoperative Management of Scaphoid Fractures: A Retrospective Review of 159 998 Patients

BACKGROUND

The purpose of the present study was to assess whether an association exists between cannabis use and nonunion among patients with acute scaphoid fractures initially treated nonoperatively.

METHODS

Using the PearlDiver national data set (2010-2020), adult patients with a scaphoid fracture were identified. Patients initially treated with nonoperative management were selected, and 3 subgroups were defined: non-cannabis/non-tobacco (non-users), tobacco-only, cannabis-only. Matched cohorts for each subgroup controlled for age, sex, and comorbidities. Nonunion rates at 6 months, 12 months, and 2 years after fracture diagnosis were determined for each subgroup's matched cohort. Rates of subsequent nonunion surgery were also determined. Multivariable analysis was then done to determine potential associations.

RESULTS

A total of 159 998 scaphoid fracture patients were identified. The non-users' group exhibited a nonunion rate of 7.7%. The nonunion rates for the tobacco-only and cannabis-only groups (11.8% and 10.1% respectively) were significantly greater than that of the non-users group. Based on multivariable analysis, cannabis use and tobacco use were individually associated with a greater risk of scaphoid nonunion as well as subsequent nonunion surgery at 6 months, 12 months, and 2 years after index fracture.

CONCLUSION

Documented cannabis use in the electronic medical record is associated with an increased risk of scaphoid nonunion and subsequent nonunion surgery. Further studies are necessary to clarify if this association can be contributed solely to cannabis use, to mixing cannabis or tobacco, or to other variables. In the meantime, physicians can counsel their patients on this potential association and increased risk.

Arthroscopic Versus Open Bone Grafting and Internal Fixation of Scaphoid Nonunion-A Systematic Review

Background

Scaphoid nonunion often requires surgical management involving the combination of a bone graft and internal fixation to restore the carpal alignment and length. While traditionally, the scaphoid waist nonunions have been treated with open bone grafts, with the advent of arthroscopy, bone graft reconstruction can now be carried out as an arthroscopic assisted minimally invasive procedure. We aimed to compare outcomes between open and arthroscopic bone grafting in the treatment of scaphoid nonunion.

Methods

A review protocol was established according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PubMed/Medline, Cochrane, Embase, and Google Scholar were searched for articles on open and arthroscopic bone grafting for scaphoid nonunion with a minimum 12 month follow-up. The primary outcome was union rates in the two techniques. Secondary outcomes were changes in pain scores, complications, functional outcomes using different scoring systems, grip strength, range of motion at the wrist, and radiological parameters for restoring normal carpal alignment.

Results

Forty studies reporting on 1534 wrists were included (1152 open, 382 arthroscopic). The union rate was 93.4% and 93.2% with open and arthroscopic techniques, respectively. The functional scores were comparable between the two techniques. All patients had a reduction in their pain scores. The radiological outcome parameters were not reported by any of the studies in the arthroscopic group.

Conclusion

While bone grafting with both open and arthroscopic techniques for scaphoid nonunion showed comparable union rates and functional scores, further research is needed to assess the radiological outcomes of the arthroscopic technique.

What Is the Optimal Method of Fixation for Scaphoid Nonunion Relative to the Location of the Lesion?

INTRODUCTION

Scaphoid nonunion is a typical complication of scaphoid fractures, with the nonunion rate varying by the location of the scaphoid. The current widely used method for treating scaphoid nonunion, which is challenging for surgeons, is the headless compression screw (HCS). Various surgical approaches, such as the scaphoid plate, have been proposed to address the problem of screw fixation; however, no consensus exists regarding the optimal treatment method. This study focused on analyzing appropriate treatment methods based on the anatomical location of the scaphoid nonunion.

METHODS

Ninety-seven patients with scaphoid nonunion were treated between 2008 and 2023. All patients underwent treatment using 1 HCS or scaphoid volar locking plate with nonvascularized bone graft from the distal radius depending on the scaphoid's location. The scaphoid angle and bone union were confirmed using radiological examinations. The clinical evaluations included range of motion, pain, grip strength, and functional wrist scores.

RESULTS

Fifty-seven patients were included in the final analysis. In the screw group, 26 patients (26/42 [62%]) obtained a bone union, and all 15 patients (15/15 [100%]) in the plate group obtained a union ( P = 0.005). In the waist group, 16 patients with screw (16/25 [64%]) and 8 using a plate (8/8 [100%]) showed bony healing. In the proximal group, 3 patients with HCS (3/9 [33%]) and 4 using plate (4/4 [100%]) showed bone union. In the distal group, 7 patients with a screw (7/8 [87%]) and 3 with the plate (3/3 [100%]) showed bone union. Significant differences were found in the waist ( P = 0.047) and proximal groups ( P = 0.026), but not in the distal group ( P = 0.521). All groups showed improved radiological angles associated with the scaphoid and better clinical outcomes postoperatively.

CONCLUSIONS

Plate fixation was overall superior to screw fixation for scaphoid nonunion, especially in the waist and proximal poles, providing better union rates and stability. For the distal group, both methods are effective, with the choice depending on the surgeon's expertise and patient factors. The results highlight the importance of the lesion's anatomical location in selecting the appropriate fixation method.

Management of Scaphoid Nonunion With Iliac Crest Graft and K-wire Fixation: An Economically Viable Option

Purpose This study details the functional results, patient satisfaction, and cost-effectiveness of patients treated with Fisk-Fernandez surgery using iliac crest graft and K-wire for scaphoid nonunion. Materials and methods This study involved a retrospective analysis conducted between November 2022 and August 2024. Forty-two patients diagnosed with scaphoid nonunion were treated using a surgical approach that included autologous bone grafting combined with K-wire fixation to promote bone healing and stability. To enable comparison, the QuickDASH-9 score, visual analog scale (VAS), and patient-rated wrist evaluation (PRWE) score were used for both preoperative and postoperative evaluations at the final follow-up. Results Our study group received treatment for an average of 16 months post-injury, ranging from 6 to 28 months. The average time of union was six months, ranging from four to 18 months. The study significantly improved QuickDASH-9 scores, grip strength, PRWE scores, and VAS for pain. The study reported no complications, and all patients returned to their basic activities of daily living. Conclusion Results of this study show that displaced scaphoid nonunions can be successfully treated with K-wire fixation combined with iliac crest bone grafting utilizing the Fisk-Fernandez approach.

Proximal Hamate Reconstruction of Proximal Pole Scaphoid Nonunion: A Case Series and Analysis of Clinical Outcomes

BACKGROUND

Small proximal pole scaphoid nonunions present a clinical challenge influenced by fragment size, vascular compromise, deforming forces exerted through the scapholunate interosseous ligament (SLIL), and potential articular fragmentation. Osteochondral autograft options for proximal pole reconstruction include the medial femoral trochlea, costochondral rib, or proximal hamate. This study reports the clinical outcomes of patients treated with proximal hamate osteochondral autograft reconstruction.

METHODS

A retrospective review identified patients treated with this surgery from 2 institutions with a minimum 6-month follow-up. Clinical outcomes included the Visual Analog Dcale pain score, 12-item Short-Form survey, abbreviated Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, wrist and forearm range of motion (ROM), radiographic assessment, and complications. We reviewed and compared these outcomes with those of the current published literature.

RESULTS

Four patients (mean age: 24 years, 75% men) with a 12.8-month average follow-up (range: 6-20 months) were included. Radiographic union was identified in all cases by 12 weeks (range, 10-12). The average wrist ROM was 67.5% flexion/extension and 100% pronation/supination compared with the contralateral side at the final follow-up. The mean QuickDASH score was 17.6 (SD, 13). No complications were identified.

CONCLUSIONS

Proximal pole scaphoid nonunion reconstruction using autologous proximal hamate osteochondral graft demonstrated encouraging clinical and radiographic outcomes. Proximal hamate harvest involves minimal donor site morbidity without a distant operative site, uses an osteochondral graft with similar morphology to the proximal scaphoid, requires no microsurgical technique, and permits reconstruction of the SLIL using the volar capitohamate ligament.

Arthroscopic assisted versus open non-vascularized bone grafting in delayed union and nonunion of the scaphoid: a systematic review and meta-analysis

BACKGROUND

Delayed union and nonunion of the scaphoid is a common complication often requiring surgical reconstruction and bone grafting. Our goal was to systematically assess the healing time and clinical outcomes following arthroscopic-assisted versus open non-vascularized bone grafting of the scaphoid.

METHODS

A comprehensive search of the MEDLINE, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Cochrane Central databases was completed from inception to September 2023. We included randomized trials and observational studies that reported outcomes following scaphoid delayed union/nonunion comparing arthroscopic-assisted vs. open non-vascularized bone grafting. Two reviewers independently extracted data and assessed the risk of bias. One investigator assessed certainty of evidence and a senior investigator confirmed the assessment. We pooled effects using random-effects models, when possible, for all outcomes reported by more than 1 study.

RESULTS

Overall, 26 studies and 822 patients were included in the study. Very low certainty evidence demonstrated that arthroscopic-assisted surgery may decrease healing time compared to open surgery (weighted mean difference [WMD] -7.8 weeks; 95%CI -12.8 to -2.8). Arthroscopic bone grafting did not result in an improvement in union rate (relative risk 1.01; 95%CI 0.9 to 1.09). The pooled data in arthroscopic graft group showed mean time to union of 11.4 weeks (95%CI: 10.4 to 12.5) with union rate of 95% (95%CI 91-98%). A single comparative study reported very low certainty evidence that arthroscopy-assisted vs. open surgery may not have an effect on pain relief (MD 0 cm, 95%CI -0.4 to 0.5 on VAS 10 cm for pain) or improving function (MD -1.2, 95% CI -4.8 to 2.3 on 100 points DASH).

CONCLUSION AND FUTURE DIRECTIONS

Our results suggest that arthroscopic-assisted non-vascularized bone grafting may be associated with improved average weeks to heal in comparison with open surgery for scaphoid delayed union/nonunion reconstruction with overall comparable union rates. There is insufficient evidence to assess the effects of arthroscopic-assisted reconstruction on union rate, time to union, and patient-reported outcomes in patients with other important nonunion characteristics such as established humpback deformity.

Artificial intelligence for X-ray scaphoid fracture detection: a systematic review and diagnostic test accuracy meta-analysis

OBJECTIVES

Scaphoid fractures are usually diagnosed using X-rays, a low-sensitivity modality. Artificial intelligence (AI) using Convolutional Neural Networks (CNNs) has been explored for diagnosing scaphoid fractures in X-rays. The aim of this systematic review and meta-analysis is to evaluate the use of AI for detecting scaphoid fractures on X-rays and analyze its accuracy and usefulness.

MATERIALS AND METHODS

This study followed the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and PRISMA-Diagnostic Test Accuracy. A literature search was conducted in the PubMed database for original articles published until July 2023. The risk of bias and applicability were evaluated using the QUADAS-2 tool. A bivariate diagnostic random-effects meta-analysis was conducted, and the results were analyzed using the Summary Receiver Operating Characteristic (SROC) curve.

RESULTS

Ten studies met the inclusion criteria and were all retrospective. The AI's diagnostic performance for detecting scaphoid fractures ranged from AUC 0.77 to 0.96. Seven studies were included in the meta-analysis, with a total of 3373 images. The meta-analysis pooled sensitivity and specificity were 0.80 and 0.89, respectively. The meta-analysis overall AUC was 0.88. The QUADAS-2 tool found high risk of bias and concerns about applicability in 9 out of 10 studies.

CONCLUSIONS

The current results of AI's diagnostic performance for detecting scaphoid fractures in X-rays show promise. The results show high overall sensitivity and specificity and a high SROC result. Further research is needed to compare AI's diagnostic performance to human diagnostic performance in a clinical setting.

CLINICAL RELEVANCE STATEMENT

Scaphoid fractures are prone to be missed secondary to assessment with a low sensitivity modality and a high occult fracture rate. AI systems can be beneficial for clinicians and radiologists to facilitate early diagnosis, and avoid missed injuries.

KEY POINTS

• Scaphoid fractures are common and some can be easily missed in X-rays. • Artificial intelligence (AI) systems demonstrate high diagnostic performance for the diagnosis of scaphoid fractures in X-rays. • AI systems can be beneficial in diagnosing both obvious and occult scaphoid fractures.

The incidence of surgical intervention following a suspected scaphoid fracture

Aims

The underlying natural history of suspected scaphoid fractures (SSFs) is unclear and assumed poor. There is an urgent requirement to develop the literature around SSFs to quantify the actual prevalence of intervention following SSF. Defining the risk of intervention following SSF may influence the need for widespread surveillance and screening of SSF injuries, and could influence medicolegal actions around missed scaphoid fractures.

Methods

Data on SSF were retrospectively gathered from virtual fracture clinics (VFCs) across a large Scottish Health Board over a four-year period, from 1 January 2018 to 31 December 2021. The Bluespier Electronic Patient Record System identified any surgical procedure being undertaken in relation to a scaphoid injury over the same time period. Isolating patients who underwent surgical intervention for SSF was performed by cross-referencing the unique patient Community Health Index number for patients who underwent these scaphoid procedures with those seen at VFCs for SSF over this four-year period.

Results

In total, 1,739 patients were identified as having had a SSF. Five patients (0.28%) underwent early open reduction and internal fixation (ORIF). One patient (0.06%) developed a nonunion and underwent ORIF with bone grafting. All six patients undergoing surgery were male (p = 0.005). The overall rate of intervention following a SSF was 0.35%. The early intervention rate in those undergoing primary MRI was one (0.36%), compared with three in those without (0.27%) (p > 0.576).

Conclusion

Surgical intervention was rare following a SSF and was not required in females. A primary MRI policy did not appear to be associated with any change in primary or secondary intervention. These data are the first and largest in recent literature to quantify the prevalence of surgical intervention following a SSF, and may be used to guide surveillance and screening pathways as well as define medicolegal risk involved in missing a true fracture in SSFs.

The Role of Artificial Intelligence in the Identification and Evaluation of Bone Fractures

Artificial intelligence (AI), particularly deep learning, has made enormous strides in medical imaging analysis. In the field of musculoskeletal radiology, deep-learning models are actively being developed for the identification and evaluation of bone fractures. These methods provide numerous benefits to radiologists such as increased diagnostic accuracy and efficiency while also achieving standalone performances comparable or superior to clinician readers. Various algorithms are already commercially available for integration into clinical workflows, with the potential to improve healthcare delivery and shape the future practice of radiology. In this systematic review, we explore the performance of current AI methods in the identification and evaluation of fractures, particularly those in the ankle, wrist, hip, and ribs. We also discuss current commercially available products for fracture detection and provide an overview of the current limitations of this technology and future directions of the field.

Scaphoid Nonunions Treated with Nonvascularized Bone Grafting and Screw Fixation

Background  Vascularized bone grafting with screw fixation is currently considered the treatment of choice for scaphoid nonunions with avascular necrosis (AVN) of the proximal pole. A viable alternative to using vascularized bone grafts for scaphoid nonunions with AVN is nonvascularized bone grafting with screw fixation. Question  What are the functional outcomes of patients with scaphoid nonunions and associated proximal pole AVN who are treated with nonvascularized distal radius bone grafting and screw fixation? Patients and Methods  Eight scaphoid nonunions with AVN, which received nonvascularized distal radius bone graft and screw fixation, underwent a retrospective review. Range of motion, strength, and Disabilities of the Arm, Shoulder, and Hand (DASH) scores were obtained. Follow-up X-rays were compared with immediate postoperative X-rays. Results  At a mean follow-up of 88.9 months, thumb palmar abduction and radial abduction were significantly higher on the operative side ( p  = 0.28 and 0.49, respectively). Extension/flexion arc was significantly lower in the operative wrist ( p  = 0.148). There was no significant difference between the operative and nonoperative sides with regard to strength. The median postoperative DASH score was 2.9 (interquartile range [IQR]: 8.3). There was no progression of osteoarthritis when immediate postoperative and follow-up X-rays were compared. Radiographic union was observed in six of the seven (85.7%) patients who were able to return to the office for follow-up radiographs. The mean scapholunate and radioscaphoid angles measured on X-rays were within normal anatomic range postoperatively. Conclusions  Using nonvascularized distal radius bone graft and screw fixation in the treatment of scaphoid nonunions with associated AVN has favorable radiologic and functional outcomes and should be considered a viable treatment option for this difficult problem.

Scaphoid nonunion: a novel modification of Matti-Russe technique with enhanced recovery and full clinical and radiographic union

BACKGROUND

A scaphoid fracture is a common injury affecting the wrist joint. A fracture of the carpus scaphoid can heal uneventfully or be complicated by non-union. Scaphoid non-union can result in persistent wrist pain, and with functional difficulties affecting all activities of daily living of the patients, this disability is expected to be significant since most of these patients are young active adults.

HYPOTHESIS

Extensive removal of the bone from the scaphoid, with the application of a large amount of cancellous bone graft and fixation with two to three wires, could lead to a high union rate and a good functional outcome.

METHODS

Eighteen patients with scaphoid fracture non-union were recruited during their visit to the upper limb clinic at our institute. Demographic data were collected, and data regarding comorbidities, smoking, manual work, and others were recorded. Data regarding the interval between injury and surgery, time to radiographic union, and functional wrist scores were reported as well.

RESULTS

A cohort of 18 patients was included. The mean age of patients was 30 years; most of our patients were healthy (83.3%), and more than two-thirds were smokers (72.2%). The mean follow-up time was 18 months (1.5 years), 15 patients (83.3%) achieved radiographic unions by 2-3 months, and the remaining 3 patients (16.7%) achieved radiographic unions by (4-5) months, i.e., all patients achieved successful radiographic unions by 5 months at maximum. The mean Mayo score for our series was 83.6 (± 12.4), with 5 patients (27%) achieved ≥ 95% which indicates a significantly high functioning wrist in our cohort.

CONCLUSION

Our modified technique with enhanced stability from using three k-wires can achieve full clinical and radiographic unions and result in enhanced recovery postoperatively with cast immobilization limited to 6 weeks total.

LEVEL OF EVIDENCE

IV Case series study.

Cancellous compression bone grafting using headless screw as a strut in scaphoid nonunion by a single volar approach

PURPOSE

An array of fixation and grafting techniques for scaphoid nonunion have been described over time, achieving varied results pertaining to union and scaphoid alignment. The aim of this study was to check for union rates and correction of scaphoid parameters achieved by our technique of using screw as a strut and cancellous compression grafting harvested from the distal radius by a single volar approach.

METHODS

Retrospective analysis of all patients operated by the said technique was done from 2013 to 2019. Thirty-eight patients including 36 males and two females in the age range of 20-56 years were analyzed. Union rates, change in scaphoid alignment parameters and graft site characteristics were documented.

RESULTS

Of the patients analyzed, 5/38 were nonunions of proximal pole, 19/38 of waist and 14/38 were of distal pole which included nonunions of cystic type or with humpback deformity. Patients were followed up for an average of 22.2 months and union was achieved in all cases with a mean period of 15.7 ± 3.7 weeks. There was significant improvement in the scaphoid alignment postoperatively. One case of implant migration and one case of scaphoid nonunion advanced collapse were noted. The mean duration of donor site healing was noted to be 16.9 ± 2.5 weeks except two outliers which took longer time. There were no cases of donor site fracture or other complications.

CONCLUSION

Union rates, correction of scaphoid parameters and minimal complications justifies this technique as a novel one in the management of scaphoid nonunion at all levels, with minimal donor site morbidity and attained by the single volar approach.

Evaluation of free vascularized medial femoral condyle bone grafts in the treatment of avascular scaphoid waist nonunion

OBJECTIVES

The aim of this study was to evaluate the medial femoral condyle (MFC) bone graft procedure for scaphoid waist nonunion with avascular necrosis on magnetic resonance imaging or prior surgery failure.

PATIENTS AND METHODS

Between June 2015 and December 2018, a total of 17 patients (16 males, 1 female; mean age: 29±8.2 years; range, 16 to 40 years) with scaphoid waist nonunion who were treated with vascularized MFC bone grafting were retrospectively analyzed. Pre- and postoperative carpal indices, grip strengths for both hands, range of motion, Visual Analog Scale (VAS) pain score, Quick Disabilities of the Arm, Shoulder, and Hand (QDASH) score, and Mayo Wrist Score (MWS) were evaluated.

RESULTS

After vascularized MFC bone graft surgery, 15 patients healed and returned to work without any limitations. Ten patients of left scaphoid nonunion and seven cases of right scaphoid nonunion were treated; for eight of these patients, the operation was on the dominant side. Eight of these patients were smokers. The mean follow-up was 22.4±5.8 months. The mean hand grip strength was increased from 74.5 to 84% on the contralateral side (p<0.05). The average revised carpal height ratio improved from 1.57 to 1.59 (p<0.05) and the scapholunate angle changed from 56.9° to 51.6° (p<0.05).

CONCLUSION

The MFC bone grafting is one of the best surgical procedures for small defects such as scaphoid waist nonunion with high union rates, good functional outcomes, and minimal donor site morbidity.

Assessing the risk of re-fracture related to the percentage of partial union in scaphoid waist fractures

Aims

There is ambiguity surrounding the degree of scaphoid union required to safely allow mobilization following scaphoid waist fracture. Premature mobilization could lead to refracture, but late mobilization may cause stiffness and delay return to normal function. This study aims to explore the risk of refracture at different stages of scaphoid waist fracture union in three common fracture patterns, using a novel finite element method.

Methods

The most common anatomical variant of the scaphoid was modelled from a CT scan of a healthy hand and wrist using 3D Slicer freeware. This model was uploaded into COMSOL Multiphysics software to enable the application of physiological enhancements. Three common waist fracture patterns were produced following the Russe classification. Each fracture had differing stages of healing, ranging from 10% to 90% partial union, with increments of 10% union assessed. A physiological force of 100 N acting on the distal pole was applied, with the risk of refracture assessed using the Von Mises stress.

Results

Overall, 90% to 30% fracture unions demonstrated a small, gradual increase in the Von Mises stress of all fracture patterns (16.0 MPa to 240.5 MPa). All fracture patterns showed a greater increase in Von Mises stress from 30% to 10% partial union (680.8 MPa to 6,288.6 MPa).

Conclusion

Previous studies have suggested 25%, 50%, and 75% partial union as sufficient for resuming hand and wrist mobilization. This study shows that 30% union is sufficient to return to normal hand and wrist function in all three fracture patterns. Both 50% and 75% union are unnecessary and increase the risk of post-fracture stiffness. This study has also demonstrated the feasibility of finite element analysis (FEA) in scaphoid waist fracture research. FEA is a sustainable method which does not require the use of finite scaphoid cadavers, hence increasing accessibility into future scaphoid waist fracture-related research.

The Snuffbox: The Effect of Smokeless Tobacco Use on Scaphoid Fracture Healing

BACKGROUND

Smoking has been demonstrated to be a risk factor for nonunion of scaphoid fractures, but it is unclear if chewing tobacco confers similar risk. The purpose of this study was to evaluate rates of bone-related complications after nonsurgical management of scaphoid fractures in smokeless tobacco users compared with matched control subjects and compared with smokers.

METHODS

A retrospective cohort study was conducted using the PearlDiver database. For patients who underwent nonsurgical management of scaphoid fractures, 212 smokeless tobacco users and 6,048 smokers were matched 1:4 with control subjects (n = 848 and 24,192, respectively) and 212 smokeless tobacco users were matched 1:4 with 848 smokers. Rates of bone-related complications within 2 years of initial injury were compared using multivariable logistic regression.

RESULTS

From weeks 12 through 104 after initial injury, compared with control subjects who do not use tobacco, the smokeless tobacco cohort demonstrated markedly higher rates of nonunion (5.7% vs 2.7%, OR: 2.07). Compared with control subjects who do not use tobacco, the smoking cohort demonstrated markedly higher rates of nonunion (4.3% vs 2.6%, OR: 1.91), repair of nonunion (1.5% vs 0.9%, OR: 1.87), and four corner fusion and proximal row carpectomy (0.3% vs 0.1%, OR: 3.17). Smokeless tobacco use was markedly underdiagnosed in the adult male cohort of unilateral scaphoid fractures with 2 years of follow-up found in the database (372 of 25,704, 1.45%) relative to Centers for Disease Control estimates for adult male smokeless tobacco use (4.5%) ( P < 0.001).

CONCLUSION

Given the higher rates of nonunion diagnoses after nonsurgical management in this cohort, surgeons should consider asking all patients with scaphoid fractures if they use smokeless tobacco or smoke and consider adding this to the patient's intake history to further identify patients at risk for nonunions. Tobacco cessation counseling is indicated for all tobacco users, including smokeless with scaphoid fractures.

Clinical Validation of an Artificial Intelligence Model for Detecting Distal Radius, Ulnar Styloid, and Scaphoid Fractures on Conventional Wrist Radiographs

This study aimed to assess the feasibility and performance of an artificial intelligence (AI) model for detecting three common wrist fractures: distal radius, ulnar styloid process, and scaphoid. The AI model was trained with a dataset of 4432 images containing both fractured and non-fractured wrist images. In total, 593 subjects were included in the clinical test. Two human experts independently diagnosed and labeled the fracture sites using bounding boxes to build the ground truth. Two novice radiologists also performed the same task, both with and without model assistance. The sensitivity, specificity, accuracy, and area under the curve (AUC) were calculated for each wrist location. The AUC for detecting distal radius, ulnar styloid, and scaphoid fractures per wrist were 0.903 (95% C.I. 0.887-0.918), 0.925 (95% C.I. 0.911-0.939), and 0.808 (95% C.I. 0.748-0.967), respectively. When assisted by the AI model, the scaphoid fracture AUC of the two novice radiologists significantly increased from 0.75 (95% C.I. 0.66-0.83) to 0.85 (95% C.I. 0.77-0.93) and from 0.71 (95% C.I. 0.62-0.80) to 0.80 (95% C.I. 0.71-0.88), respectively. Overall, the developed AI model was found to be reliable for detecting wrist fractures, particularly for scaphoid fractures, which are commonly missed.

Outcomes after arthroscopic treatment for scaphoid nonunion using ipsilateral radius bone graft and a headless compression screw: a comparison between the patients with and without avascular necrosis

PURPOSE

To determine whether avascular necrosis can affect clinical outcomes or the union incidence after arthroscopic bone grafting for the treatment of scaphoid nonunion.

METHODS

This retrospective comparative study included thirty-four patients with scaphoid nonunion that underwent arthroscopic bone graft from the ipsilateral radius and internal fixation. The patients were divided into two cohorts (group A, with avascular necrosis, n = 15; group B, without avascular necrosis, n = 19) based on pre-operative magnetic resonance imaging findings. Additionally, the patients were grouped in accordance with the location of nonunion (waist, n = 27; proximal pole, n = 7). The mean follow-up was 20.7 months (range 12.0-40.0 months). Clinical outcomes, including the visual analog scale (VAS) pain score, grip strength, range of motion (ROM), Mayo Wrist Score (MWS), and Disabilities of the Arm, Shoulder, and Hand (DASH) score, were evaluated. Radiographic measurements for carpal bone alignment were assessed as well.

RESULTS

Union rates did not differ between groups (group A, 93.3%; group B, 94.7%: p = 0.863), and the post-operative VAS pain score, ROM, and MWS were similar at follow-up for a minimum of one year. DASH and grip strength were significantly better in group B, but the intergroup differences were minimal (mean DASH 11.9 versus 9.6; mean grip strength 77.5% versus 95.4% of contralateral side). There was no significant intergroup difference in mean time to achieving union (group A, 14.9 weeks; group B, 14.6 weeks; p = 0.900). In post-operative radiographic assessments, no significant intergroup differences were noted in any of the parameters. Subgroup analysis regarding the location of nonunion showed there were no significant intergroup differences in union rates, mean time to achieving union, and clinical outcome measures at the last post-operative follow-up.

CONCLUSIONS

Arthroscopic bone grafting and internal fixation in the treatment of scaphoid nonunion provided good union rates and satisfactory outcomes regardless of vascularity status.

Volar Plating of Scaphoid Fractures: A Retrospective Case Series

BACKGROUND

The purpose of this study was to evaluate the rate of union of scaphoid fractures managed with volar plating and assess postoperative complications.

METHODS

Retrospective consecutive case series of 28 patients with scaphoid fractures, 9 acute and 19 chronic nonunions, undergoing surgical fixation with volar scaphoid plating by a single surgeon between 2013 and 2019. Patients were followed up for a minimum of 3 months with scaphoid bony union being confirmed on radiograph or computed tomography. Postoperative complications and need for plate removal were recorded.

RESULTS

Overall union rate of 96% with all 19 chronic nonunions demonstrating radiological union and 1 of 9 acute fractures not uniting and requiring revision surgery. The only postoperative complication identified was symptomatic plate impingement which necessitated plate removal in 57% of cases.

CONCLUSIONS

This case series demonstrates volar plating of scaphoid fractures can be used as an alternative technique to achieve union.

How Is Scaphoid Malunion Defined: A Systematic Review

BACKGROUND

Abnormal scaphoid alignment after fracture is used as an indication for fixation. Acceptable alignment after reduction and fixation of scaphoid fractures is not well defined. We systematically reviewed the literature to identify how scaphoid malunion is currently defined and by what parameters.

METHODS

A systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Multiple databases were searched for studies published in the English language that reported on outcomes after scaphoid malunion and included measurements to define malunions. Radiographic scaphoid measurement parameters were collected. Clinical outcome measures recorded included grip strength, wrist range of motion, and patient-reported outcome measures. Study quality was analyzed using the Methodological Index for Non-Randomized Studies (MINORS) criteria. Descriptive summaries of the studies are presented.

RESULTS

The initial search yielded 1600 articles. Ten articles (161 participants, 93% males, mean age = 28.3 + 6.3 years, mean MINORS score = 10.2 + 1.6) were included and analyzed. Scaphoid malunion was defined if the lateral intrascaphoid angle (LISA) was >45° (3 articles), LISA >35° (1 article), and height to length ratio >0.6 (3 articles). Four out of 5 studies found no significant associations between patient outcomes and degree of scaphoid malunion measured on imaging.

CONCLUSIONS

There is a lack of consensus for defining scaphoid malunion on imaging and absence of correlation between findings on imaging and patient outcomes. Future studies defining scaphoid malunion should be appropriately powered, incorporate measures of intrarater and interrater reliabilities for all reported imaging measurements, and utilize validated patient-reported outcome measures to reflect that malunion is associated with inferior outcomes meaningful to patients.

Arthroscopic treatment of stable nonunion, unstable nonunion, or nonunion of the scaphoid with early degenerative radioscaphoid arthritis

BACKGROUND

This study was designed to analyze the clinical follow-up results (minimum of 2 years) in patients with stable nonunion, unstable nonunion, or nonunion of the scaphoid with early degenerative radioscaphoid arthritis (Lichtman classification stage I-III) treated with arthroscopic osteosynthesis with autogenous bone graft.

METHODS

We retrospectively recruited 44 consecutive patients with scaphoid fracture nonunion treated with arthroscopy-assisted percutaneous internal fixation with autogenous bone grafts from January 2010 to November 2019. We recorded union and return to activity and analyzed data with regular clinical follow-up at a mean duration of 33 months (range 24-46 months). Clinical (i.e., visual analog scale pain score, grip strength, and range of motion), radiographic, and functional (Mayo Modified Wrist Score (MMWS)) outcomes at the final follow-up were compared with the preoperative assessments and analyzed in patients with different stages.

RESULTS

We confirmed union in 39 of the 44 patients (88.6%) after a mean 15.4 weeks post-operatively according to clinical examinations and standard radiography. All clinical parameters improved significantly. For the MMWS, there were 25 excellent and 14 good results. Of the 44 patients, 40 (90.9%) returned to work or sports activities at their preinjury levels. Comparisons of the outcomes between patients in different stages of scaphoid nonunion revealed no significant difference in the aspect of union rate, VAS pain score, and functional score improvement.

CONCLUSIONS

Arthroscopic osteosynthesis with autogenous bone grafts is a reliable and minimally invasive method for achieving nonunion healing and improving clinical outcomes in stage I-III scaphoid nonunion.

LEVEL OF EVIDENCE

Level IV, case series.

The Many Faces of Marrow Necrosis

Depending on the age and location within the skeleton, bone marrow can be mostly fatty or hematopoietic, and both types can be affected by marrow necrosis. This review article highlights the magnetic resonance imaging findings of disorders in which marrow necrosis is the dominant feature.Fatty marrow necrosis is detected on T1-weighted images that show an early and specific finding: the reactive interface. Collapse is a frequent complication of epiphyseal necrosis and detected on fat-suppressed fluid-sensitive sequences or using conventional radiographs. Nonfatty marrow necrosis is less frequently diagnosed. It is poorly visible on T1-weighted images, and it is detected on fat-suppressed fluid-sensitive images or by the lack of enhancement after contrast injection.Pathologies historically "misnamed" as osteonecrosis but do not share the same histologic or imaging features of marrow necrosis are also highlighted.

Arthroscopic treatment of unstable scaphoid fracture and nonunion with two headless compression screws and distal radius bone graft

BACKGROUND

The treatment of unstable scaphoid fracture and nonunion remains a challenging problem for hand surgeons. Minimally invasive treatment has become the preferred method of treatment.

PURPOSE

This study introduces the arthroscopic technique with two headless compression screws (HCS) fixation and distal radius bone grafting for the treatment of unstable scaphoid fracture and nonunion, aiming to evaluate its clinical and radiological outcomes.

METHODS

It was a retrospective study. From January 2019 to February 2021, a total of 23 patients were included in the current study. Among them, 13 patients with unstable scaphoid fracture underwent arthroscopic treatment with two HCS; 10 patients with scaphoid nonunion underwent arthroscopic treatment with two HCS and a distal radius bone graft. The range of motion of the wrist, visual analog scale (VAS), grip strength, the Modified Mayo Wrist Score (MMWS), the Patient-Rated Wrist Evaluation (PRWE) score, and the Disability of the Arm, Shoulder and Hand (DASH) score were collected at preoperatively and the final follow-up. A computed tomography scan of the wrist was performed on each patient to analyze for union and postoperative osteoarthritis during the follow-up period.

RESULTS

Significant improvement was only observed in wrist extension. Clinical outcomes including grip strength, VAS pain score, MMWS, PRWE score, and DASH score were significantly improved at the final follow-up. In the subgroup analysis, both patients stabilized with either two HCS or a distal radius bone graft and two HCS have improved clinical outcomes after surgery, respectively. All patients achieved union. No screw fixation failure occurred, and no other postoperative complication was observed in any of the patients.

CONCLUSIONS

The arthroscopic technique with two-HCS fixation and distal radius bone grafting is a reliable and effective technique for the treatment of unstable scaphoid fracture and nonunion, providing satisfactory union rates and clinical outcomes.

Scaphoid Nonunion: A Review of Surgical Strategies

The scaphoid is predisposed to nonunion after fracture because of its tenuous blood supply and propensity for delayed diagnosis. Many surgical techniques exist and continue to be developed to treat scaphoid non-unions. However, with variability in patient presentation, differences in nonunion location and type, and multiple bone graft sources and fixation options, selecting a surgical strategy proves a difficult task. The goal of this article is to provide an updated review of surgical strategies used to treat scaphoid nonunions. Particular attention is paid to methods of fixation as well as the ongoing debate over indications for structural and vascularized bone grafting. [Orthopedics. 2022;45(5):e235-e242.].

Clinical and Epidemiological Features of Scaphoid Fracture Nonunion: A Hospital-Based Study in Beijing, China

Objective

Studies exploring the epidemiological characteristics of scaphoid fracture nonunion are important to understand the causes and lead to effective prevention strategy. However, such knowledge is limited especially in China. This study aims to reveal the clinical and epidemiological features of scaphoid fracture nonunion in Chinese patients.

Methods

This was a retrospective study, which was based on patients with scaphoid fracture nonunion treated in a Chinese national orthopedic referral center from 1 August 2009 to 1 August 2020. The basic demographic and clinical characteristics, including gender, age at diagnosis of scaphoid fracture nonunion, dominant hand, the location of fracture, the side, the causes of the injury, age of the injury, age of the treatment for scaphoid fracture nonunion, and the delay period, were retrieved from the medical records. The patients were divided into a non‐delay group and a delay group based on whether they had visited the doctor within 1 month after the injury. Scaphoid fracture was classified into the proximal, waist, and distal fractures according to the location. The t‐test or Mann–Whitney U test was used to compare the difference between groups when the dependent variable is continuous, while a chi‐square test was used when the dependent variable is categorical.

Results

A total of 363 patients were included in this study. The mean age at the diagnosis of scaphoid fracture nonunion was 32 (ranging from 14 to 78). Waist fracture nonunion (76.5%) was most common. Among the 169 patients who sought medical care within 1 month after the injury (non‐delay group), more than half (90 cases) were misdiagnosed. 23 cases could not recall the injury, so the time of delay could not be determined. Among the 171 patients who did not seek medical care for acute injury (delay group), the average time was 52 months between the initial injury and the treatment. The proportion of waist nonunions was higher among patients in the delay group than that in the non‐delay group.

Conclusions

Nonunion of scaphoid fracture is caused mainly by delayed treatment and misdiagnosis in China, suggesting that timely treatment and improved diagnosis could lower the prevalence. The fracture location may be a factor contributing to the delaying of seeking medical care.

Arthroscopic bone graft and fixation for proximal scaphoid nonunions

AIMS

This study aims to report the outcomes in the treatment of unstable proximal third scaphoid nonunions with arthroscopic curettage, non-vascularized bone grafting, and percutaneous fixation.

METHODS

This was a retrospective analysis of 20 patients. All cases were delayed presentations (n = 15) or failed nonoperatively managed scaphoid fractures (n = 5). Surgery was performed at a mean duration of 27 months (7 to 120) following injury with arthroscopic debridement and arthroscopic iliac crest autograft. Fracture fixation was performed percutaneously with Kirschner (K)-wires in 12 wrists, a headless screw in six, and a combination of a headless screw and single K-wire in two. Clinical outcomes were assessed using grip strength, patient-reported outcome measures, and wrist range of motion (ROM) measurements.

RESULTS

Intraoperatively, established avascular necrosis of the proximal fragment was identified in ten scaphoids. All fractures united within 16 weeks, confirmed by CT. At a mean follow-up of 31 months (12 to 64), there were significant improvements in the Patient-Rated Wrist Evaluation, Mayo Wrist Score, abbreviated Disabilities of the Arm, Shoulder and Hand score, wrist ROM, grip strength, and the patients' subjective pain score. No peri- or postoperative complications were encountered.

CONCLUSION

Our data indicate that arthroscopic bone grafting and fixation with cancellous autograft is a viable method in the treatment of proximal third scaphoid nonunions, regardless of the vascularity of the proximal fragment. Cite this article: Bone Joint J 2022;104-B(8):946-952.

Vascularized Bone Grafting in the Treatment of Scaphoid Nonunion: A Clinical and Functional Outcome Study

Background  A malreduction or missed scaphoid fracture may lead to nonunion or avascular necrosis (AVN). The aim of this study was to analyze the radiological and clinical outcome of patients with scaphoid nonunion (SN), who were treated with 1,2-intercompartmental supraretinacular artery pedicled vascularized bone graft (1,2-ICSRA-VBG) fixed with K-wires or screws between 2014 and 2018. Methods  Radiological assessment included posteroanterior, lateral, oblique, and angled posteroanterior projection. The wrist active joint range of motion was assessed with a universal goniometer, and grip and pinch strength with a dynamometer. The disabilities of the arm, shoulder and hand (DASH) questionnaire was used to evaluate functionality. Statistical analysis was performed using SPSS software (v16.0). Results  A total of 68 patients (65 male) with a mean age 29.7 ± 8.5 years were evaluated in the study, and union was achieved in 55 (81%). A total of 45 (66%) patients had scaphoid waist fracture and 48 (71%) had AVN. Fixation was achieved with K-wires in 48 of the patients, and with screw in 20. The mean length of follow-up was 31.6 ± 14.6 (12-72) months. The mean radioulnar range of motion and DASH scores improved significantly after treatment ( p  < 0.001, p ≤ 0.001). Conclusions  The findings of this study showed that scaphoid unions can be treated successfully with high rates of union using the 1,2-ICSRA-VBG. This surgical technique requires special surgical experience. The functional outcome of patients improved after treatment, although smoking was found to be an important factor affecting functional results.

Pelvic Avulsion Fractures in Adolescent Athletes: Analyzing the Effect of Delay in Diagnosis

OBJECTIVE

To evaluate whether delay in the diagnosis of pelvic avulsion fractures in young athletes leads to prolonged treatment and prolonged return toward sport activities, whether fractures at certain locations are associated with a greater risk of diagnostic delay, and what reasons may exist for delay in diagnosis.

DESIGN

Retrospective chart review of young patients who presented with pelvic region avulsion fracture to a community-based sports medicine clinic over a 19-year period.

SETTING

Private practice, primary care sports medicine clinic.

PATIENTS

Patients younger than 20 years diagnosed with pelvic region avulsion fracture.

INTERVENTIONS

None, this was a retrospective study.

MAIN OUTCOME MEASURES

Clearance for return toward sport activities.

RESULTS

Two hundred twenty-five cases were reviewed for reasons for delay in diagnosis; 208 cases met criteria for the duration of treatment and return to play activities portions of the study. The mean time from date of injury diagnosis was 19.59 days, and the mean duration from date of injury to clearance for return to play advancement was 67.20 days. Duration of treatment varied slightly depending on timing of diagnosis, whereas duration from date of injury to clearance for return to play advancement varied greatly depending on diagnostic delay. Those who did not sense a "pop" at the time of injury were more likely to experience diagnostic delay, as were athletes with ischial tuberosity fractures. The most common cause of diagnostic delay was patient/family decision on when to seek care; misdiagnosis as a muscle strain was also common.

CONCLUSIONS

Diagnostic delay of adolescent pelvic avulsion fractures may unnecessarily prevent athletes from returning to play within an optimal time frame. Our observations highlight a need for educating athletes and their families on when to seek initial or follow-up medical care as well as educating medical providers regarding the diagnosis of pelvic avulsion fractures.

Anatomical Engineering and 3D Printing for Surgery and Medical Devices: International Review and Future Exponential Innovations

Three-dimensional printing (3DP) has recently gained importance in the medical industry, especially in surgical specialties. It uses different techniques and materials based on patients' needs, which allows bioprofessionals to design and develop unique pieces using medical imaging provided by computed tomography (CT) and magnetic resonance imaging (MRI). Therefore, the Department of Biology and Medicine and the Department of Physics and Engineering, at the Bioastronautics and Space Mechatronics Research Group, have managed and supervised an international cooperation study, in order to present a general review of the innovative surgical applications, focused on anatomical systems, such as the nervous and craniofacial system, cardiovascular system, digestive system, genitourinary system, and musculoskeletal system. Finally, the integration with augmented, mixed, virtual reality is analyzed to show the advantages of personalized treatments, taking into account the improvements for preoperative, intraoperative planning, and medical training. Also, this article explores the creation of devices and tools for space surgery to get better outcomes under changing gravity conditions.

Osteopenia in Scaphoid Fracture: An Indicator of Good Prognosis or Is it Cause for Concern?: A Case Report

CASE

A 32-year-old man sustained a scaphoid waist fracture and was managed nonoperatively in a short-arm cast. Radiographic follow-up at 6 weeks showed marked loss of radiodensity of the whole scaphoid, although the fracture was clinically united. Patchy ossification at 3 months was followed by the complete restoration of radiodensity and trabecular pattern by 20 weeks. The patient had an uneventful and full functional recovery.

CONCLUSION

This, perhaps unreported, finding seems to be an indicator of preserved vascularity in scaphoid fractures. Further research/reporting of this radiological pattern in these fractures will help improve their understanding and management.

Fracture, nonunion and postoperative infection risk in the smoking orthopaedic patient: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to analyse negative effects of smoking in orthopaedic and trauma patients.

A PubMed search was carried out for studies published until July 2020 regarding effects of smoking on fracture risk, nonunion, infection after orthopaedic surgery, and persisting nonunion after scaphoid nonunion surgery. Random effects models calculated for outcome parameters, and relative risks (RR) with 95% confidence intervals are provided. No adjustments for covariates were made. Heterogeneity was assessed with Higgins’ I2, publication bias with Harbord’s p (Hp), sensitivity analysis performed on funnel plots and quality of studies was analysed using the Newcastle-Ottawa Scale.

Of 3362 retrieved entries, 69 were included in the final analysis. Unadjusted RR for smokers to develop vertebral (six studies, seven entries; RR: 1.61; p = 0.008; I2 = 89.4%), hip (11 studies, 15 entries; RR: 1.28; p = 0.007; I2 = 84.1%), and other fractures (eight studies, 10 entries; RR: 1.75; p = 0.019; I2 = 89.3%) was significantly higher. Postoperative infection risk was generally higher for smokers (21 studies; RR: 2.20; p < 0.001; I2 = 58.9%), and remained upon subgroup analysis for elective spinal (two studies; RR: 4.38; p < 0.001; I2 = 0.0%) and fracture surgery (19 studies; RR: 2.10; p < 0.001; I2 = 58.5%). Nonunion risk after orthopaedic (eight studies; RR: 2.15; p < 0.001; I2 = 35.9%) and fracture surgery (11 studies; RR: 1.85; p < 0.001; I2 = 39.9%) was significantly higher for smokers, as was persisting nonunion risk after surgery for scaphoid nonunion (five studies; RR: 3.52; p < 0.001; I2 = 0.0%). Sensitivity analysis for each model reduced heterogeneity whilst maintaining significance (all I2 < 20.0%).

Smoking has a deleterious impact on fracture incidence, and (subsequent) development of nonunions and postoperative infections.

Cite this article: EFORT Open Rev 2021;6:1006-1019. DOI: 10.1302/2058-5241.6.210058

A meta-analysis of union rate after proximal scaphoid fractures: terminology matters

Heterogeneity in the anatomical definition of 'proximal' affects the comparison of outcomes of these scaphoid fractures. This study aims to review published outcomes of all variants to determine both, differences in terminology, and union rate based upon definition. A literature search was conducted to identify articles that reported descriptions and union rate of all acute (<8 weeks of injury) proximal scaphoid fractures in adult patients (>16 years old). Proximal fractures were grouped as reported ('third', 'pole', 'fifth' or 'undefined'). The data were pooled using a fixed-effects method, and a meta-analysis was conducted to compare relative risk (RR) of non-union against non-proximal fractures. Qualitative analysis of 12 articles included three main definitions: 'proximal' (1 article), 'proximal third' (3 articles), and 'proximal pole' (8 articles). Only 6 articles adopted a specific anatomical or ratio description. In a pooled meta-analysis of union rates (15 articles), 'proximal third' and 'proximal pole' fractures demonstrated a relative risk (RR) of non-union of 2.3 and 3.4 in comparison to non-proximal fractures, respectively. Operative management yielded lower non-union rates than non-operative for all fracture types (6% vs. 18%). In conclusion, non-union risk varies depending on definition, with non-standardised classifications adding heterogeneity to reported outcomes. We recommend an approach utilizing fixed anatomical landmarks on plain radiographs (referencing scaphoid length and scapho-capitate joint) to standardise reporting of proximal fracture union in future studies. Abbreviations: CI: confidence intervals; CT: computer tomography; Df: degrees of freedom; DL: dersimonian and laird estimator; MRI: magnetic resonance imaging; NICE: national institute for health and care excellence; OTA: orthopaedic trauma association; PA: posterior-anterior; PRISMA: preferred reporting items for systematic reviews and meta analyses; RCT: randomised controlled trial; RR: relative risk; SNAC: scaphoid non-union advanced collapse; UK: United Kingdom.

Delayed diagnosis of carpal scaphoid fracture in a young boy

Carpal scaphoid fracture is rare in children and is important to recognize early because of an increased risk for serious complications including non-union, avascular necrosis, and osteoarthritis. In the skeletally immature patient, a scaphoid fracture can easily escape detection due to clinical and diagnostic imaging interpretation errors. We report complete healing of a pediatric scaphoid non-union fracture after a remarkable delay in diagnosis and emphasize the considerable biological potential of the immature skeleton, coupled with proper stabilization, for good clinical outcomes.

Bone Morphogenetic Protein in Scaphoid Nonunion: A Systematic Review

Background  Scaphoid nonunion can lead to carpal collapse and osteoarthritis, a painfully debilitating problem. Bone morphogenetic protein (BMP) has been successfully implemented to augment bone healing in other circumstances, but its use in scaphoid nonunion has yielded conflicting results. Case Description  The purpose of this study is to assess the outcomes and complications of scaphoid nonunion treated surgically with BMP. Literature Review  A literature review of all available journal articles citing the use of BMP in scaphoid nonunion surgery from 2002 to 2019 was conducted. We included studies that used BMP as an adjunct to surgical treatment for scaphoid nonunions in both the primary and revision settings with computed tomography determination of union. Demographic information, dose of BMP, tobacco use, outcomes, and complications were recorded. A total of 21 cases were included from four different studies meeting inclusion criteria. Clinical Relevance  The union rates were 90.5% overall, 100% for primary surgeries, and 77.8% for revision surgeries. Five patients (24%) experienced 11 complications, including four cases (19%) of heterotrophic ossification. Use of BMP in scaphoid nonunion surgery resulted in a 90.5% overall union rate but was also associated with complications such as heterotopic ossification. All included studies used BMP to augment bone graft, screw or wire fixation, or a combination of methods. The efficacy of BMP in scaphoid nonunion is unclear, and a sufficiently powered, randomized controlled trial is needed to determine optimal fixation methods, dosing, and morbidity of the use of BMP. Level of Evidence  This is a Level IC, therapeutic interventional study.

Volar Plating versus Headless Compression Screw Fixation of Scaphoid Nonunions: A Meta-analysis of Outcomes

Background  Headless compression screw fixation with bone grafting has been the mainstay of treatment for scaphoid nonunion for the past several decades. Recently, locked volar plate fixation has gained popularity as a technique for scaphoid fixation, especially for recalcitrant or secondary nonunions. Purpose  The purpose of this meta-analysis was to compare union rates and clinical outcomes between locked volar plate fixation and headless compression screw fixation for the treatment of scaphoid nonunions. Methods  A literature search was performed for studies documenting treatment outcomes for scaphoid nonunions from 2000 to 2020. Inclusion criteria consisted of (1) average age > 18 years, (2) primary study using screw fixation, plate fixation, or both, with discrete data reported for each procedure, and (3) average follow-up of at least 3 months. Exclusion criteria consisted of studies with incomplete or missing data on union rates. Data from each study was weighted, combined within treatment groups, and compared across treatment groups using a generalized linear model or binomial distribution. Results  Following title and full-text review, 23 articles were included for analysis. Preoperatively, patients treated with plate fixation had significantly longer time from injury to surgery and were more likely to have failed prior surgical intervention. There was no significant difference between union rates at 92 and 94% for screw and plate fixation, respectively. However, plate fixation resulted in longer time to union and lower modified Mayo wrist scores. Conclusion  Patients treated with locked volar plate fixation were more likely to be used for recalcitrant or secondary nonunions. There was no statistically significant difference in union rates between screw and plate fixation. The results from this meta-analysis support the select use of locked volar plate fixation for scaphoid nonunion, especially recalcitrant nonunions and those that have failed prior surgical repair.

Development and Validation of a Convolutional Neural Network for Automated Detection of Scaphoid Fractures on Conventional Radiographs

Purpose

To compare the performance of a convolutional neural network (CNN) to that of 11 radiologists in detecting scaphoid bone fractures on conventional radiographs of the hand, wrist, and scaphoid.

Materials and Methods

At two hospitals (hospitals A and B), three datasets consisting of conventional hand, wrist, and scaphoid radiographs were retrospectively retrieved: a dataset of 1039 radiographs (775 patients [mean age, 48 years ± 23 {standard deviation}; 505 female patients], period: 2017-2019, hospitals A and B) for developing a scaphoid segmentation CNN, a dataset of 3000 radiographs (1846 patients [mean age, 42 years ± 22; 937 female patients], period: 2003-2019, hospital B) for developing a scaphoid fracture detection CNN, and a dataset of 190 radiographs (190 patients [mean age, 43 years ± 20; 77 female patients], period: 2011-2020, hospital A) for testing the complete fracture detection system. Both CNNs were applied consecutively: The segmentation CNN localized the scaphoid and then passed the relevant region to the detection CNN for fracture detection. In an observer study, the performance of the system was compared with that of 11 radiologists. Evaluation metrics included the Dice similarity coefficient (DSC), Hausdorff distance (HD), sensitivity, specificity, positive predictive value (PPV), and area under the receiver operating characteristic curve (AUC).

Results

The segmentation CNN achieved a DSC of 97.4% ± 1.4 with an HD of 1.31 mm ± 1.03. The detection CNN had sensitivity of 78% (95% CI: 70, 86), specificity of 84% (95% CI: 77, 92), PPV of 83% (95% CI: 77, 90), and AUC of 0.87 (95% CI: 0.81, 0.91). There was no difference between the AUC of the CNN and that of the radiologists (0.87 [95% CI: 0.81, 0.91] vs 0.83 [radiologist range: 0.79-0.85]; P = .09).

Conclusion

The developed CNN achieved radiologist-level performance in detecting scaphoid bone fractures on conventional radiographs of the hand, wrist, and scaphoid.Keywords: Convolutional Neural Network (CNN), Deep Learning Algorithms, Machine Learning Algorithms, Feature Detection-Vision-Application Domain, Computer-Aided DiagnosisSee also the commentary by Li and Torriani in this issue.Supplemental material is available for this article.©RSNA, 2021.

A vascularized bone graft harvested from the dorsal base of the third metacarpal bone for the treatment of scaphoid nonunion

The purpose of this retrospective study was to introduce the use of an alternative vascularized bone graft for treating scaphoid non-union. The vascularized bone graft was harvested from the dorsal base of the third metacarpal bone. From May 2014 to September 2017, 29 patients with scaphoid non-union were treated. Grip and pinch strengths were compared to the contralateral side. The patients rated wrist joint pain on a visual analogue scale. Wrist function was assessed on Mayo Wrist Score. p < 0.05 was considered statistically significant. 18 scaphoids healed at 6 weeks and the other 11 at 16 weeks. Follow-up ranged from 28 to 73 months, for a mean 48 months. At final follow-up, mean wrist flexion had improved from 65° (range, 51°-81°) preoperatively to 72° (range, 61-78°) (p > 0.05), for a contralateral value of 74° (range, 65°-86°). Mean extension had improved from 56° (range, 44°-72°) to 60° (range, 47°-76°) (p > 0.05) for a contralateral value of 66° (range, 52°-80°). Mean wrist pain improved from 4 (range, 3-8) to 2 (range, 0-4) (p < 0.05). Mean pinch strength improved from 6.4 kg (range, 5.2-7.3 kg) to 8.6 kg (6.1-9.9 kg) (p < 0.05). Mayo Wrist Score improved from 49 (range, 10-65) to 92 (range, 70-100) (p < 0.05). Transferring a vascularized bone graft harvested from the base of the third metacarpal bone was an effective alternative for the treatment of scaphoid non-union, achieving bone healing and normal wrist function without significant donor-site morbidity. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

[Osteophyte-induced impingement reduces range of motion in humpback deformity of incorrectly healed scaphoid reconstruction]

BACKGROUND

The gold standard in the treatment of scaphoid pseudarthrosis is reduction, interposition of an iliac crest graft and stabilization with a headless bone (Herbert) screw, aiming to reduce the frequently observed humpback deformity. This study correlated the extent of humpback deformity after scaphoid reconstruction to clinical and radiological postoperative parameters.

MATERIAL AND METHODS

Between 2008 and 2010 a total of 56 patients with scaphoid pseudarthrosis were surgically treated. Of the patients 34 could be included in this retrospective study. The average follow-up period was 7.3 months. The humpback deformity was evaluated by computed tomography (CT) scan performed along the long axis of the scaphoid. The disability of the arm, shoulder and hand (DASH) score, grip strength (Jamar), range of motion (RoM), Mayo wrist score (MWS) and other parameters were used to determine the clinical outcome. The patients were divided into two groups: 1) no or only slight humpback deformity (<25°), 2) severe humpback deformity (>45°).

RESULTS

The RoM and DASH scores were slightly better for the first group. The second group had a significantly increased incidence of osteophyte formation (p < 0.05) and decreased RoM (-16°).

CONCLUSION

It is postulated that the main disadvantage of an nonreduced humpback deformity is the increased occurrence of osteophyte formation in the dorsal aspect of the scaphoid. This can cause an impingement during extension and leads to a significant restriction of movement of the wrist.

LEVEL OF EVIDENCE

III.

A Retrospective Review of Differences in Complication Rates between Dorsal Percutaneous and Mini-Open Surgical Fixation of Scaphoid Fractures

Objective  We retrospectively reviewed the complications of 80 cases of scaphoid screw fixation in acute fractures and early nonunions comparing dorsal percutaneous and mini-open approaches. Methods  We performed a chart review of all patients who underwent surgical fixation of a scaphoid fracture or a nascent nonunion using a dorsal percutaneous or dorsal mini-open technique by a single surgeon. We collected data on patient demographics, including age and smoking status, time to surgery, fracture type, union, and the major and minor complications that occurred in each group. Fisher's exact tests were used to compare the complication rates between the groups. Results  We identified 80 patients who underwent surgical fixation. Of these, 44 underwent percutaneous fixation and 36 underwent mini-open fixation. All fractures went on to heal. There was a total of five complications identified. There were no major complications in the percutaneous group, but one major complication in the mini-open group (a delayed union that eventually healed at 6 months). There were two minor complications in each group. There was no statistically significant difference in total, major, or minor complication rates between the groups. Conclusions  This study suggests that a dorsal percutaneous surgical technique for scaphoid fracture repair does not affect the complication rate despite prior literature to the contrary. Both techniques analyzed produce excellent rates of union with very low complication rates. Surgeon-specific technique rather than operative approach or exposure may be responsible for previously reported complication rates in the fixation of scaphoid fractures. Level of Evidence  This is a level III, therapeutic study.

Radiographic evaluation of vascularity in scaphoid nonunions: A review

Scaphoid fractures, particularly those that occur more proximally, are unreliable in achieving union due to the retrograde blood supply of the scaphoid bone. Vascular compromise is associated with the development of nonunions and avascular necrosis of the proximal pole. Due to the tenuous blood supply of the scaphoid, it is imperative that the vascularity be assessed when creating diagnostic and treatment strategies. Early detection of vascular compromise via imaging may signal impending nonunion and allow clinicians to perform interventions that aid in restoring perfusion to the scaphoid. Vascular compromise in the scaphoid presents a diagnostic challenge, in part due to the non-specific findings on plain radiographs and computed tomography. Magnetic resonance imaging techniques have dramatically improved our ability to assess the blood supply to the scaphoid and improve time to intervention. This review aims to summarize these advances and highlights the importance of imaging in assessing vascular compromise in scaphoid nonunion and in reperfusion following surgical intervention.

[3D Imaging for the analysis of scaphoid fractures and non-unions]

The aim of the present study is to give an overview over the possibilities of 3D imaging in the analysis of scaphoid fractures and non-unions and to discuss them on the base of case studies and literature.

Determining diagnosis of scaphoid healing: Comparison of cone beam CT and X-ray after six weeks of immobilization

PURPOSE

To assess the accuracy and reliability of using cone beam computed tomography (CBCT) compared to X-ray six weeks after injury for predicting scaphoid union.

MATERIALS AND METHODS

Overall; 52 patients with scaphoid fractures between April 2018 and March 2019 were prospectively included in this study. The mean age was 34.52 (13-88) years, and the gender ratio male/female 43/9. Of the fractures, 26 had occurred on the right side, and 26 on the left side. In total, 28 % of patients were manual workers. All patients underwent X-ray and CBCT six weeks after injury. Four readers, two radiologists, and two hand surgeons analyzed the findings using double-blinded X-ray and CBCT and categorized fractures as consolidated based on a 50 % visibility threshold concerning trabecular bridges. Proximal pole sclerosis, communition, cyst formation, and humpback deformity were similarly analyzed for all cases. Agreement between readers was calculated using Kappa, and sensitivity, specificity, and accuracy using RStudio software. The gold standard was the radiologic and clinical follow-up for all patients at two months.

RESULTS

Inter-reader agreement between the four readers was moderate concerning X-ray (0.543) but substantial concerning CBCT (0.641). It was almost perfect between seniors regarding CBCT (Kappa = 0.862). Sensitivity, specificity, and accuracy were 0.75-0.78, 0.4, and 0.61-0.64, respectively, for two readers regarding CBCT. The X-ray values were 0.65-0.71, 0.35-0.4, and 0.53-0.59, respectively.

CONCLUSION

CBCT proves more accurate and reliable than X-ray for diagnosing scaphoid union at an early follow-up and prevents longer immobilization and interruption of activity or work.

Outcomes of Local Bone Graft and Fixation of Proximal Pole Scaphoid Nascent Nonunions and Nonunions

Background  Fractures of the proximal pole of the scaphoid have an increased risk of nonunion due to its tenuous blood supply. The optimal treatment of proximal pole scaphoid nonunions remains controversial. Objectives  To review a single surgeon's experience with proximal pole scaphoid nascent nonunions (delayed unions) and nonunions that underwent surgical fixation with a cannulated headless compression screw and local autologous bone graft from the distal radius. Patients and Methods  After obtaining Institutional Review Board approval, the electronic medical record of one tertiary care center was queried for patients with the diagnosis of "proximal pole scaphoid fractures" who underwent surgical fixation by a single surgeon over an 11-year period (2006-2017). Fifteen patients met initial query criteria; upon review of records, four patients were excluded due to the acute nature of the fracture, and one was excluded as surgical fixation included a vascularized bone graft. Results  The final study cohort consisted of 10 patients with a total of 10 proximal pole scaphoid nonunions. Almost all of the patients in this study were male (9/10 [90%]), and sporting activities were the most common mechanism of injury (8/10 [80%]). Volumetric measurements of the scaphoid fractures on computed tomography (CT) revealed that the mean total volume of the scaphoid was 2.4 ± 0.48 cm ³ and the mean volume of the proximal pole fragment was 0.38 ± 0.15 cm ³ . Postoperative CT scans were performed at a mean of 12.4 weeks (range: 8-16 weeks), with seven (7/10 [70%]) showing signs of complete union and three (3/10 [30%]) demonstrating partial union. None of the patients required additional procedures and there were no complications. Conclusions  Our results suggest that proximal pole scaphoid fractures with delayed union and nonunion treated with surgical fixation and autologous local bone graft heal without the need for more complex vascularized procedures. The volume of the proximal pole fragment did not correlate with increased risk of ongoing nonunion after the index procedure. Level of Evidence  This is a Level IV, case series study.

Carpal Collapse After Scaphoid Nonunion: A Novel Combined Approach to the 1,2 Intercompartmental Supraretinacular Artery Radial Flap

Purpose

Scaphoid nonunion remains a major problem in hand surgery. The 1,2 intercompartmental supraretinacular artery flap (1,2 ICSRA), as first described by Zaidemberg et al, is widely used with reported union rates of approximately 80%. However, its use is limited in the case of associated carpal collapse as in dorsal intercalated segmental instability (DISI) and humpback deformity. In this study, we present a novel approach to this flap enabling the correction of associated carpal collapse.

Methods

Between 2006 and 2015, 9 patients with scaphoid nonunion or delayed union with carpal collapse were treated with a vascularized bone flap based on the 1,2 ICSRA using a combined volar and dorsal approach. Immobilization in a short-arm cast was applied for 8 weeks. Union rates, correction of DISI and humpback deformity, as well as clinical end points were noted. In addition, scapholunate (SL) angles were measured using 2 accepted radiological techniques, employing either the scaphoid midline axis or its proximal radiological landmarks as a reference.

Results

All cases united and a median time to bone consolidation of 4 months (range, 2–5 months) was observed. Preoperative DISI deformities (n = 4) were corrected in all patients. Humpback deformities (n = 5) were also corrected. Two patients had repeat surgery: one for K-wire removal after bony consolidation and the other for neuropathic pain.

Conclusions

The 1,2 ICSRA bone flap is a reliable treatment for scaphoid nonunion associated with carpal collapse. This combined volar and dorsal approach permits the correction of DISI and humpback deformity without compromising the scaphoid vascular supply, which eliminates the need to use free bone flaps from other sites. In this series, we observed a 100% union rate. Two patients required reoperation for symptomatic hardware and dorsal wrist pain linked to superficial neuritis.

Type of study/level of evidence

Therapeutic IV.

Factors Associated with Scaphoid Nonunion following Early Open Reduction and Internal Fixation

Background  Nonunion after open reduction and internal fixation (ORIF) of scaphoid fractures is reported in 5 to 30% of cases; however, predictors of nonunion are not clearly defined. Objective  The purpose of this study is to determine fracture characteristics and surgical factors which may influence progression to nonunion after scaphoid fracture ORIF. Patients and Methods  We performed a retrospective case-control study of scaphoid fractures treated by early ORIF between 2003 and 2017. Inclusion criteria were surgical fixation within 6 months from date of injury and postoperative CT with minimum clinical follow-up of 6 months to evaluate healing. Forty-eight patients were included in this study. Nonunion cases were matched by age, sex, and fracture location to patients who progressed to fracture union in the 1:2 ratio. Results  This series of 48 patients matched 16 nonunion cases with 32 cases that progressed to union. Fracture location was proximal pole in 15% (7/48) and waist in 85% (41/48). Multivariate regression demonstrated that shorter length of time from injury to initial ORIF and smaller percent of proximal fracture fragment volume were significantly associated with scaphoid nonunion after ORIF (63 vs. 27 days and 34 vs. 40%, respectively). Receiver operating curve analysis revealed that fracture volume below 38% and time from injury to surgery greater than 31 days were associated with nonunion. Conclusion  Increased likelihood for nonunion was found when the fracture was treated greater than 31 days from injury and when fracture volume was less than 38% of the entire scaphoid. Level of Evidence  This is a Level III, therapeutic study.

Biomechanical Strength of Retrograde Fixation in Proximal Third Scaphoid Fractures

Background: Current techniques for fixation of proximal pole scaphoid fractures utilize antegrade fixation via a dorsal approach endangering the delicate vascular supply of the dorsal scaphoid. Volar and dorsal approaches demonstrate equivalent clinical outcomes in scaphoid wrist fractures, but no study has evaluated the biomechanical strength for fractures of the proximal pole. This study compares biomechanical strength of antegrade and retrograde fixation for fractures of the proximal pole of the scaphoid. Methods: A simulated proximal pole scaphoid fracture was produced in 22 matched cadaveric scaphoids, which were then assigned randomly to either antegrade or retrograde fixation with a cannulated headless compression screw. Cyclic loading and load to failure testing were performed and screw length, number of cycles, and maximum load sustained were recorded. Results: There were no significant differences in average screw length (25.5 mm vs 25.6 mm, P = .934), average number of cyclic loading cycles (3738 vs 3847, P = .552), average load to failure (348 N vs 371 N, P = .357), and number of catastrophic failures observed between the antegrade and retrograde fixation groups (3 in each). Practical equivalence between the 2 groups was calculated and the 2 groups were demonstrated to be practically equivalent (upper threshold P = .010). Conclusions: For this model of proximal pole scaphoid wrist fractures, antegrade and retrograde screw configuration have been proven to be equivalent in terms of biomechanical strength. With further clinical study, we hope surgeons will be able to make their decision for fixation technique based on approaches to bone grafting, concern for tenuous blood supply, and surgeon preference without fear of poor biomechanical properties.

Comparison of Shape Memory Staple and Gelled Platelet-Rich Plasma versus Shape Memory Staple alone for the Treatment of Waist Scaphoid Nonunion: A Single-Center Experience

Purpose  The aim of this study was to analyze the results of two different methods of surgical treatment of waist scaphoid nonunions (SNUs). We retrospectively analyzed data from 87 patients referred to our department from January 2010 to December 2017 who were surgically treated for waist SNU. Methods  The mean period of time passed from trauma was 11.2 (±5.6) months. Patients were divided into two groups based on surgical treatment received: volar exposure osteosynthesis with shape memory staple (SMS) (group A) and volar exposure osteosynthesis with SMS and gelled platelet-rich plasma (GPRP) application at the bone defect level (group B). A cast (thumb excluded) was maintained for 4 weeks. Healing was checked clinically (pain, QuickDASH [Disabilities of the Arm, Shoulder, and Hand] score, Mayo Wrist Score) and radiologically (standard X-ray). Results  Union was achieved in 40 patients in group A (95.2%) and in all patients in group B (45 patients; 100%). A statistically significant difference was observed in the improvement of the Mayo Wrist Score, QuickDASH score, and pain (measured through the visual analog scale) after 3 months from surgery ( p  = 0.02). Conclusion  SMS is effective in treating waist SNU at more than 6 months from trauma. GPRP application can improve bone healing and upper limb function. Level of Evidence  This is a retrospective observational Level III study.