Scaphoid Reconstruction.

Surgical strategies for scaphoid nonunions become more complex based on time from injury to treatment. The decision-making process, however, can follow a logical sequence. Scaphoid nonunions less than 1 year after trauma and no carpal malalignment can be treated with percutaneous screw fixation under fluoroscopic and/or arthroscopic guidance. Reinterventions or patients with avascular proximal poles that do not need substantial grafts are reliably treated with pedicle vascularized bone grafts. Resection of the distal pole of the scaphoid is a good option in old nonunions or after a failed scaphoid procedures. When there are radioscaphoid degenerative changes, salvage procedures such as proximal row carpectomy (PRC) should be considered.

The Non-Union Scoring System: an interobserver reliability study.

PURPOSE: The Non-Union Scoring System (NUSS) aims to classify non-unions according to their severity and relate them to four treatment categories. The main purpose of this study was to evaluate the reliability of the NUSS. In addition we assessed its clinical validity. METHODS: Forty-four Patients with a tibia non-union between 2005 and 2015 were included in this study. Data from all included patients were scored independently by three observers according to the NUSS criteria. The interobserver agreement was evaluated using the intraclass correlation coefficient (ICC). The interobserver agreement of the Weber-Cech system was assessed using Fleiss' kappa. Finally, the clinical validity of the NUSS was analysed by comparing outcomes of the actual treatment groups to the proposed treatment groups following from the NUSS scores. RESULTS: Forty-four patients were included. The comparison of NUSS scores between observers showed substantial agreement [ICC; 0.78 (0.67-0.86)]. The comparison of the Weber-Cech classification between observers showed only fair agreement [Fleiss κ; 0.30 (0.17-0.42)]. The χ2 test for the treatment groups according to the NUSS and the treatments at index procedure showed an independent relation (χ2 = 5.794, 6 degrees of freedom, p: 0.447). In contrast, the proposed treatment strategy corresponds well to the definitive treatment (χ2 = 29.963, 9 degrees of freedom, p < 0.001). CONCLUSION: We conclude that the NUSS is both a reliable and valid system to classify non-unions.

Volar Plate Fixation to Treat Scaphoid Nonunion: A Case Series With Minimum 3 Years of Follow-Up.

PURPOSE: Several options exist for treating scaphoid nonunion. For selected cases, some authors recommend using a volar buttress plate. The aim of the study was to report the clinical and radiological outcomes achieved at a minimum of 3 years' follow-up of treating scaphoid nonunion with a scaphoid volar plate. METHODS: We retrospectively reviewed 15 patients with symptomatic scaphoid nonunion treated with scaphoid plate osteosynthesis and a bone graft from the volar aspect of the distal radius between January 2011 and November 2013. The patients' average age was 32 years (range, 21-62 years). No patient had undergone previous scaphoid surgery. Clinical assessments included wrist range of motion (ROM), grip strength, and a 10-point visual analog scale rating of pain. Further subjective assessment was performed using validated measurement tools. All patients underwent plain radiography with 6 different views and computed tomography before and after surgery. The scapholunate angle was measured to evaluate carpal alignment. RESULTS: The mean follow-up period was 42 months (range, 36-51 months). Bone union was obtained in 13 of 15 patients (87%) at an average of 5 months (range, 3-8 months) after surgery. Significant improvements in the scapholunate angle and visual analog scale pain score were observed. However, both wrist ROM and grip strength remained significantly decreased relative to the opposite side (62% and 55% of normal, respectively). Four patients experienced hardware complications: plate breakage (1 scaphoid) and screw back-out (3 scaphoids). Impingement between the radial styloid and the scaphoid plate was identified in 6 patients. Five patients required additional surgery to remove the plate. CONCLUSIONS: Our study indicates unsatisfactory results treating scaphoid nonunion with a volar scaphoid plate. Although the rate of union was comparable with that of other series, we noted more complications. We are concerned about both the high proportion of hardware complications and required secondary surgical procedures. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Non-structural cancellous bone graft and headless compression screw fixation for treatment of scaphoid waist non-union.

PURPOSE: Scaphoid fracture commonly occurs around the mid-third of the scaphoid, and non-union of this fracture has several treatment options. The authors performed autologous cancellous bone graft from the iliac crest and headless compression screw fixation for the treatment of Mack-Lichtman type II scaphoid waist non-union. The purpose of this study was to determine whether this procedure was effective in achieving bony union and restoration of alignment. METHODS: Medical records and radiographs of 30 patients who underwent cancellous bone graft and headless compression screw fixation for non-union of scaphoid waist fracture were retrospectively reviewed. There were 28 men and 2 women, with a mean age of 32.8 years (range: 21-63). The mean time to surgery was 10 months (range: 3-25) and mean follow-up was 37.5 months (range: 15-52). The authors analyzed bony union, lateral intrascaphoid angle, scapholunate angle, radiolunate angle and scaphoid length on radiographs and evaluated the Modified Mayo wrist score (MMWS) as a functional outcome. RESULTS: Bony union was achieved in all cases. The lateral intrascaphoid angle improved from 40° to 32° (P<0.001). The scapholunate angle also improved from 61° to 56° (P=0.009). The radiolunate angle decreased from 8° to 4° (P=0.048) and scaphoid length increased from 22mm to 26mm (P<0.001) postoperatively. Wrist motion and MMWS improved significantly at last follow-up. However, there were no significant differences between scaphoid deformity correction angle and pre- to post-operative difference in MMWS. CONCLUSIONS: Non-structural autologous cancellous bone graft from the iliac crest and headless screw fixation provided reliable results and can be one of the effective treatment options for patients with symptomatic Mack-Lichtman type II non-union in the mid-third of the scaphoid. LEVEL OF EVIDENCE: Level III.

An update on the Pauwels classification.

BACKGROUND: Femoral neck fractures typically occur as a result of high-energy mechanisms among non-geriatric patients. Complications, including femoral neck shortening, non-union, and avascular necrosis, are relatively common after the internal fixation of this fracture pattern. These complications have serious effects on young patients. The Pauwels classification, which is the first biomechanical classification for femoral neck fractures, is still frequently used to determine and prescribe the appropriate treatment for femoral neck fractures. However, we lack a unified standard for measuring the Pauwels angle, which may make the classification unreliable. Understanding the relationship between the Pauwels classification and the complications arising from the internal fixation of femoral neck fractures is necessary. Meanwhile, a Pauwels type III femoral neck fracture among young adults, which involves a high shear load at the fracture site, is difficult to treat successfully. In addition, the recognized internal fixation for this fracture pattern remains uncertain. MAIN BODY: This review aims to provide an update on the viewpoint on the Pauwels classification including the measurement of the Pauwels angle and to present evidence to prove the aforementioned relationship. Moreover, this article also discusses the optimal internal fixation for femoral neck fractures based on the Pauwels classification. CONCLUSION: A unified standard of measurement should be established for the Pauwels classification, which is still frequently used in the literature and in determining appropriate treatment for femoral neck fractures, to achieve a credible classification. In addition, more randomized, multicentric, and prospective trials should be conducted in the future to clearly understand the relationship between the Pauwels classification and complications arising from the internal fixation of femoral neck fractures and, consequently, to explore ideal fixations for a Pauwels type III femoral neck fracture.

Epidemiology of Fracture Nonunion in 18 Human Bones.

Importance: Failure of bone fracture healing occurs in 5% to 10% of all patients. Nonunion risk is associated with the severity of injury and with the surgical treatment technique, yet progression to nonunion is not fully explained by these risk factors. Objective: To test a hypothesis that fracture characteristics and patient-related risk factors assessable by the clinician at patient presentation can indicate the probability of fracture nonunion. Design, Setting, and Participants: An inception cohort study in a large payer database of patients with fracture in the United States was conducted using patient-level health claims for medical and drug expenses compiled for approximately 90.1 million patients in calendar year 2011. The final database collated demographic descriptors, treatment procedures as per Current Procedural Terminology codes; comorbidities as per International Classification of Diseases, Ninth Revision codes; and drug prescriptions as per National Drug Code Directory codes. Logistic regression was used to calculate odds ratios (ORs) for variables associated with nonunion. Data analysis was performed from January 1, 2011, to December 31, 2012. Exposures: Continuous enrollment in the database was required for 12 months after fracture to allow sufficient time to capture a nonunion diagnosis. Results: The final analysis of 309 330 fractures in 18 bones included 178 952 women (57.9%); mean (SD) age was 44.48 (13.68) years. The nonunion rate was 4.9%. Elevated nonunion risk was associated with severe fracture (eg, open fracture, multiple fractures), high body mass index, smoking, and alcoholism. Women experienced more fractures, but men were more prone to nonunion. The nonunion rate also varied with fracture location: scaphoid, tibia plus fibula, and femur were most likely to be nonunion. The ORs for nonunion fractures were significantly increased for risk factors, including number of fractures (OR, 2.65; 95% CI, 2.34-2.99), use of nonsteroidal anti-inflammatory drugs plus opioids (OR, 1.84; 95% CI, 1.73-1.95), operative treatment (OR, 1.78; 95% CI, 1.69-1.86), open fracture (OR, 1.66; 95% CI, 1.55-1.77), anticoagulant use (OR, 1.58; 95% CI, 1.51-1.66), osteoarthritis with rheumatoid arthritis (OR, 1.58; 95% CI, 1.38-1.82), anticonvulsant use with benzodiazepines (OR, 1.49; 95% CI, 1.36-1.62), opioid use (OR, 1.43; 95% CI, 1.34-1.52), diabetes (OR, 1.40; 95% CI, 1.21-1.61), high-energy injury (OR, 1.38; 95% CI, 1.27-1.49), anticonvulsant use (OR, 1.37; 95% CI, 1.31-1.43), osteoporosis (OR, 1.24; 95% CI, 1.14-1.34), male gender (OR, 1.21; 95% CI, 1.16-1.25), insulin use (OR, 1.21; 95% CI, 1.10-1.31), smoking (OR, 1.20; 95% CI, 1.14-1.26), benzodiazepine use (OR, 1.20; 95% CI, 1.10-1.31), obesity (OR, 1.19; 95% CI, 1.12-1.25), antibiotic use (OR, 1.17; 95% CI, 1.13-1.21), osteoporosis medication use (OR, 1.17; 95% CI, 1.08-1.26), vitamin D deficiency (OR, 1.14; 95% CI, 1.05-1.22), diuretic use (OR, 1.13; 95% CI, 1.07-1.18), and renal insufficiency (OR, 1.11; 95% CI, 1.04-1.17) (multivariate P < .001 for all). Conclusions and Relevance: The probability of fracture nonunion can be based on patient-specific risk factors at presentation. Risk of nonunion is a function of fracture severity, fracture location, disease comorbidity, and medication use.

Retrograde percutaneous screw fixation for scaphoid type II non-union in Schernberg zones 2 to 4: a series of 38 cases.

Regardless of the treatment used, 25 to 45% of scaphoid fractures do not heal. Open surgery compromises vascularization and destabilizes ligament attachments. The aim of this retrospective study was to assess the value of retrograde percutaneous screw fixation of Alnot stage IIA and IIB scaphoid non-union in Schernberg zones 2 to 4. This series included 38 patients with a mean age of 31 years. Based on the Alnot classification, there were 16 stage IIA non-unions (12 in zone 3 and 4 in zone 2 according to the Schernberg classification) and 22 stage IIB non-unions (9 in zone 3 and 13 in zone 2). The time elapsed between the initial trauma and the surgical treatment was 10 months on average. Percutaneous retrograde fixation was performed with a cannulated 2.7mm compression screw. At 25 months follow-up, 31 of the non-union cases had healed (81.6%), of which 14 were stage IIA (87.5%) and 17 were stage IIB (77.3%), after an average 6.3 months. Average pain was 1.6. The average Quick DASH was 17.3/100. Compared to the opposite side, the average range of motion was 84.8% in flexion, 84.7% in extension, 98.9% in pronation, 96.5% in supination, 96.8% in ulnar deviation and 86.4% in radial deviation. The grip strength was 80.4% of the contralateral side. Seven patients did not heal after screw fixation; four of them healed after additional electromagnetic stimulation and three after addition of a vascularized bone graft. Based on this study's results, stage IIA non-unions can heal with simple retrograde percutaneous screw fixation. The same procedure could be enough for stage IIB non-union cases, however we recommend adding a cancellous bone graft by arthroscopy. Open surgery procedures are preferred when percutaneous procedures have failed.

Validation of the Non-Union Scoring System in 300 long bone non-unions.

INTRODUCTION: Non-union of long bones is a significant consequence of fracture treatment. The ideal classification for non-union of long bones would give sufficient significant information to the orthopaedic surgeon to enable good management of the treatment required and to facilitate the creation of comparable study groups for research purposes. The Non-Union Scoring System (NUSS) is a new scoring system to assist surgeons in the choice of the correct treatment in non-union surgery. The aim of this study was to determine the evidence supporting the use of the NUSS classification in the treatment of non-unions of long bones and to validate the treatment algorithm suggested by this scoring system. MATERIALS AND METHODS: A total of 300 patients with non-union of the long bones were included in the clinical study. RESULTS: A radiographic and clinical healing was reached in 60 of 69 non-unions (86%) in group 1 (0-25 points), in 102 of 117 non-unions (87%) in group 2 (26-50 points), and in 69 of 84 (82%) in group 3 (51-75 points). The mean time to clinical healing was 7.17 ± 1.85 months in group 1, 7.30 ± 1.72 months in group 2 and 7.60 ± 1.49 months in group 3. The mean time to radiographic healing was 8.78 ± 2.04 months in group 1, 9.02 ± 1.84 months in group 2 and 9.53 ± 1.40 months in group 3. DISCUSSION: There are few articles in the scientific literature that examine the classification systems for non-union. CONCLUSIONS: A statistical analysis of the first results we have obtained with the use of NUSS showed significant rates of union in all the evaluated groups. This indicates that NUSS could be an appropriate scoring system to classify and stratify non-unions and to enable the surgeon to choose the correct treatment.

Hoffa nonunion, two cases treated with headless compression screws.

A coronal fracture of the distal femoral condyle is a rare entity and a nonunion even more so. The coronal fractures, also known as Hoffa fracture, more often involve the lateral than the medial condyle. Open reduction and internal fixation are the primary treatment of choice. We describe two cases of nonunion of a Hoffa fracture (one medial and one lateral). Although the nonunion fragment was not attached to any soft tissues in both cases the fragment was noted to be vital both clinically and histologically. After operative treatment, consisting of debridement, compression with use of headless screws, and liberal use of bone graft both nonunions healed. At latest follow-up, both patients had excellent function and reported no or minimal pain.

Accuracy of ICD-9 codes to identify nonunion and malunion and developing algorithms to improve case-finding of nonunion and malunion.

OBJECTIVE: To evaluate the accuracy of using ICD-9 codes to identify nonunions (NU) and malunions (MU) among adults with a prior fracture code and to explore case-finding algorithms. STUDY DESIGN: Medical chart review of potential NU (N=300) and MU (N=288) cases. True NU cases had evidence of NU and no evidence of MU in the chart (and vice versa for MUs) or were confirmed by the study clinician. Positive predictive values (PPV) were calculated for ICD-9 codes. Case-finding algorithms were developed by a classification and regression tree analysis using additional automated data, and these algorithms were compared to true case status. SETTING: Group Health Cooperative. RESULTS: Compared to true cases as determined from chart review, the PPV of ICD-9 codes for NU and MU were 89% (95% CI, 85-92%) and 47% (95% CI, 41-53%), respectively. A higher proportion of true cases (NU: 95%; 95% CI, 90-98%; MU: 56%; 95% CI, 47-66%) were found among subjects with 1+ additional codes occurring in the 12months following the initial code. There was no case-finding algorithm for NU developed given the high PPV of ICD-9 codes. For MU, the best case-finding algorithm classified people as an MU case if they had a fracture in the forearm, hand, or skull and had no visit with an NU diagnosis code in the 12-month post MU diagnosis. PPV for this MU case-finding algorithm increased to 84%. CONCLUSIONS: Identifying NUs with its ICD-9 code is reasonable. Identifying MUs with automated data can be improved by using a case-finding algorithm that uses additional information. Further validation of the MU algorithms in different populations is needed, as well as exploration of its performance in a larger sample.

Variability in the definition and perceived causes of delayed unions and nonunions: a cross-sectional, multinational survey of orthopaedic surgeons.

BACKGROUND: Despite the large number of fracture outcome studies, there remains variability in the definitions of fracture-healing. It is unclear how orthopaedic surgeons are diagnosing and managing delayed unions and nonunions in clinical practice. We aimed to explore the current opinions of orthopaedic surgeons with regard to defining, diagnosing, and treating delayed unions and nonunions in extremity fractures. METHODS: We developed a survey using previous literature, key informants in the field of orthopaedic surgery, and a sample-to-redundancy strategy. Our final survey contained four sections and twenty-nine questions focusing on demographics and surgical experience, definitions of fracture union, prognostic factors for union, and the need for clinical trials. The Internet-based survey and follow-up e-mails were continued until our a priori sample size of a minimum of 320 completed and eligible responses were collected. RESULTS: Three hundred and thirty-five surgeons completed the survey. The typical respondent was a North American, male orthopaedic surgeon or consultant over the age of thirty years who had completed trauma fellowship training, worked in an academic practice, supervised residents, and had more than six years of experience in treating orthopaedic injuries. Most surgeons endorsed a lack of standardization in definitions for delayed unions (73%) and nonunions (55%); almost all agreed that defining a delayed union and nonunion should be done on the basis of both radiographic and clinical criteria (88%). Most respondents believed that the degree of soft-tissue injury (approximately 93%), smoking history (approximately 82%), and vascular disease (approximately 76%) increased the risk of healing complications. CONCLUSIONS: Surgeons use similar prognostic factors to define and assess delayed unions and nonunions, but there is a lack of consensus in the definitions of delayed union and nonunion. The need for standardization and future randomized trials was strongly endorsed.

Small and large titanium plates are equally effective for treating mandible fractures.

PURPOSE: The use of small titanium plates for the management of mandibular fractures continues to be a source of controversy because of their load-sharing properties. The purpose of the present study was to determine whether the use of small plates for mandibular fractures is as efficacious as large plates in a large level I trauma center. MATERIALS AND METHODS: Consecutive subjects presenting with mandibular fractures were randomly allocated to the use of either small plates (group 1) or large plates (group 2). The primary predictor variable was the plate size. The primary outcome variable was fracture union. The secondary outcomes included complications and operative time. Statistical analysis was performed using the Wilcoxon rank sum test for ordinal and continuous variables and the χ(2) test or Fisher exact test for proportions. RESULTS: A total of 127 consecutive subjects with a fracture of the mandible were enrolled in the study. Of the 127 subjects, 53 completed the required follow-up of at least 6 weeks. There was no difference in the rate of fracture union between the 2 groups (P = .95). CONCLUSIONS: The study findings suggest that the use of small plates and monocortical screws for mandibular fractures results in favorable outcomes compared with using larger plates and bicortical screws.

The jones fracture classification, management, outcome, and complications: a systematic review.

BACKGROUND: The Jones fracture has been a topic of controversy ever since being first described by Sir Robert Jones himself in 1902. The aim of this review is to summarize the classification, management, outcome, and complications of this particular injury. METHODS: The authors conducted a systematic review of the scientific literature regarding the Jones fracture. RESULTS: There was no consistent approach to the Jones fracture classification. The rate of nonunion with nonoperative treatment is high in both acute and chronic cases. Surgical intervention reduces the incidence of nonunion, but the complication rate of surgery is high. CONCLUSIONS: Surgical intervention for the acute Jones fracture should be reserved for the athletic individual because there is a clear advantage in terms of time to return to sporting activity. Nonoperative treatment remains a viable alternative to surgery in all acute and delayed cases, providing there is no established nonunion and the patient is aware of the implications.

Femoral-shaft fractures and nonunions treated with intramedullary nails: the role of dynamisation.

Dynamisation of a previously interlocked intramedullary nail is believed to stimulate an osteogenic response due to increased load across the fracture site. The purpose of this study was to retrospectively investigate fracture patterns that could tolerate dynamisation without the risk of major complications. Thirty patients (24 males) with an average age of 33 years (17-90) were studied. As many as 21 suffered from a fresh femoral fracture, whereas the remaining nine patients suffered from femoral nonunions. Four patterns of osseous lesion were recognised in terms of mechanical stability under a dynamic nail and biological activity at the fracture/nonunion site: stable/hypertrophic, stable/atrophic, unstable/hypertrophic and unstable/atrophic osseous lesions. Complete union (within 6 months) occurred in 21 patients. Six fractures united within the 7th-11th post-dynamisation month and, in the remaining three cases, a nonunion developed. Significant femur shortening (>20 mm) was noticed in four patients and rotational malalignment in one patient. Logistic regression analysis revealed high odds ratio (OR=70, 95% confidence interval (CI) 2.5-1998) for the unstable/atrophic pattern of osseous lesion to develop major complications. In the unstable/atrophic pattern of osseous lesion, dynamisation should never be done, as it could lead to significant complications.

Relationship between the fracture location and the kinematic pattern in scaphoid nonunion.

PURPOSE: The purpose of this study was to obtain 3-dimensional and quantitative information regarding the pathological kinematics of the wrist with scaphoid nonunion using an in vivo and 3-dimensional motion analysis. We specifically tested the hypothesis that the fracture location is related to the kinematic pattern. METHODS: We studied wrist kinematics during wrist flexion-extension motion and radioulnar deviation in 13 patients with scaphoid nonunion, using a markerless bone registration technique. Magnetic resonance images or computed tomography (CT) images of the wrist were acquired with the wrist in the neutral and 4 extreme positions of flexion, extension, radial deviation, and ulnar deviation. Three-dimensional animations were created of the carpal motions and interfragmentary motions between the distal and proximal fragments of the scaphoid. Based on the fracture location, accurate estimates of the relative positions and orientations of the carpal bones were analyzed. RESULTS: There were 2 clear patterns of the interfragmentary motions of the scaphoid based on the fracture location. In the mobile type scaphoid nonunion (7 cases), the fracture was located distal to the apex of the scaphoid dorsal ridge (scaphoid apex), and the distal scaphoid was unstable relative to the proximal scaphoid. The distal fragment showed a "book-opening" motion from wrist flexion to extension. In the stable type scaphoid nonunion (6 cases), the fracture was located proximal to the scaphoid apex, and the interfragmentary motion was considerably less than with the distal type. CONCLUSIONS: Carpal instability following scaphoid nonunion appears to be related to whether the fracture line passes distal or proximal to the scaphoid apex, where the dorsal scapholunate interosseous ligament and the dorsal intercarpal ligament attach. Three-dimensional imaging should be considered when assessing scaphoid nonunions to identify the exact location of the fracture. This may allow the clinician to choose the best treatment option.

Classification of non-union: need for a new scoring system?

SUMMARY: A new scoring system is proposed in order to assist surgeons with the complex analysis associated with non-union surgery. Patients with non-union are rarely easily compared with one another and this has frustrated research in this field. We have therefore attributed values to clinical features based on clinical experience and research evidence, so that patients of similar complexity can be compared with one another. When greater experience with this scoring system has been gained it will be further refined and validated. We propose that surgeons with a sub specialist interest in non-union surgery use this system in reporting results, and that non- specialist surgeons use it to inform their decision to treat the fracture themselves, or refer to a sub specialist.

Treatment of scaphoid fractures and nonunions.

Scaphoid fractures are common but present unique challenges because of the particular geometry of the fractures and the tenuous vascular pattern of the scaphoid. Delays in diagnosis and inadequate treatment for acute scaphoid fractures can lead to nonunions and subsequent degenerative wrist arthritis. Improvements in diagnosis, surgical treatment, and implant materials have encouraged a trend toward early internal fixation, even for nondisplaced scaphoid fractures that could potentially be treated nonoperatively. Despite the advent of newly developed fixation techniques, including open and percutaneous fixation, the nonunion rate for scaphoid fractures remains as high as 10% after surgical treatment. Scaphoid nonunions can present with or without avascular necrosis of the proximal pole and may show a humpback deformity on the radiograph. If left untreated, scaphoid nonunions can progress to carpal collapse and degenerative arthritis. Surgical treatment is directed at correcting the deformity with open reduction and internal fixation with bone grafting. Recently, vascularized bone grafts have gained popularity in the treatment of scaphoid nonunions, particularly in cases with avascular necrosis. This article reviews current concepts regarding the treatment of scaphoid fractures and nonunions.

Functional outcome of four-corner arthrodesis for treatment of grade IV scaphoid non-union.

Functional limitations and pain are end results of scaphoid nonunion with progressive carpal collapse and radiocarpal arthritis. The aim of this study was to assess the functional outcome of four-corner arthrodesis with scaphoidectomy for the treatment of grade IV scaphoid nonunion with Scaphoid Nonunion Advanced Collapse (SNAC) stages II and III. Ten patients with symptomatic grade IV non union of the scaphoid and a mean duration of non unions of 12.1 +/- 2.81 months were treated using the four-corner arthrodesis technique. A dorsal midline longitudinal approach centered over the third metacarpal-capitate-lunate-radius axis, excision of the scaphoid, neutral alignment of the remaining carpal bones, and arthrodesis of the capitate, hamate, lunate, and triquetrum, were performed. Kirschner wires were used to secure the arthrodesis in all cases. A below-elbow thumb spica cast was applied for 3 months. Follow up period ranged from 8 to 24 months, with a mean of 16 +/- 4.7 months. All patients were assessed both functionally for pain, range of motion and grip strength, and radiographically for evidence of fusion and carpal alignment. Good results were achieved in 7 patients (70%) according to the modified Mayo Wrist Scoring Chart. There were no intraoperative complications. Postoperatively, one patient suffered superficial wound infection One patient showed dorsal impingement of the capitate and radius. Also, two patients suffered reflex sympathetic dystrophy. No patients showed deep infection or nonunion. The Four-corner Arthrodesis technique is a motion-sparing, limited arthrodesis that reliably results in pain relief, improved grip strength, and overall patient satisfaction with low associated non union and complication rates.

Definition and classification of fracture non-unions.

Classifications in general provide relevant information for clinical purposes to compose a suitable treatment strategy and for research purposes to be able to define comparable study groups. Two distinct types of non-unions are described in the established literature. In the first type the ends of the fragments are hypervascutar or hypertrophic and are capable of biologic reaction. In the second type the ends of the fragments are avascular or atrophic and are inert and incapable of biologic reaction. Hypervascular as well as avascular non-unions may be complicated by the presence of infection, poor soft-tissue quality, short peri-articular fragments or significant deformity, demanding mu[ti-stage treatment strategies with concomitant worsened prognosis and subsequent increased frequency of amputation.