A comparative study of volar locking-plate fixation with corticocancellous and pure cancellous bone grafts for scaphoid nonunion with dorsal intercalated segmental instability secondary to scaphoid humpback deformity

INTRODUCTION

Bone grafts for scaphoid nonunion with deformity include cortcicocancellous or pure cancellous bone grafts. This study compared the outcomes between two types of bone grafts when employing a volar locking-plate in patients with scaphoid nonunion with dorsal intercalated segmental instability (DISI).

PATIENTS AND METHODS

This retrospective study included 34 patients with scaphoid nonunion and DISI due to humpback deformity treated between March 2017 and January 2022. Two types of bone grafts were obtained from iliac crest. Twenty of the corticocancellous (CC) group underwent a wedge-shaped graft, while 14 patients of the pure cancellous (C-only) group received graft chips. In both groups, a 1.5-mm anatomically pre-contoured locking plate was used for fixation. Radiographic evaluations included the union rate and carpal alignment including scapholunate angle (SLA), radiolunate angle (RLA), intrascaphoid angle (ISA) and scaphoid height to length ratio (HLR). Clinical assessments encompassed wrist range-of-motion, grip strength, and patient-reported outcomes.

RESULTS

Nineteen of the 20 patients in the CC group and 12 of the 14 patients in the C-only group respectively, achieving osseous union. The mean follow-up period in CC group was 14.7 (range, 12 ∼ 24) months and that in C-only group was 12.6 (range, 12 ∼ 15) months. Postoperatively, there were no significant intergroup differences of radiographic parameters including SLA (CC; 49.9° ± 6.7° vs. C-only; 48.9° ± 3.5°, P = 0.676), RLA (1.7° ± 6.4° vs. 2.4° ± 3.3°, P = 0.74), ISA (36° ± 7.5° vs. 36.6° ± 12.2°, P = 0.881), and HLR (0.54 ± 0.09 vs. 0.53 ± 0.05, P = 0.587). Clinical outcomes, including the flexion-extension arc (137° ± 30° vs. 158° ± 33°, P = 0.122), grip strength (93.4 % ± 15.4% vs. 99.5 % ± 16.7 %, P = 0.39), Quick Disabilities of the Arm, Shoulder, and Hand scores (11.2 ± 8.3 vs. 12.5 ± 7.7, P = 0.74) and Mayo Wrist Scores (81.2 ± 13.1 vs. 89 ± 11.4, P = 0.242) also showed no significant intergroup differences.

CONCLUSIONS

Volar locking-plate fixation with pure cancellous bone grafts achieved outcomes comparable to those achieved with corticocancellous bone grafts in scaphoid nonunion with deformity, possibly due to the biomechanical advantages of the volar plate to provide structural supports.

Scaphoid Nonunions: Local Vascularized Bone Flaps

If untreated, scaphoid nonunions may progress to scaphoid nonunion advanced collapse in a substantial portion of cases and may require salvage procedures. Multiple different techniques have been described to address scaphoid nonunion. Vascularized bone flaps (VBFs) are associated with faster time to union compared with nonvascularized grafts. Because these are local pedicled flaps, they do not require microsurgical anastomoses and should be within the armamentarium of all hand surgeons. Appropriately chosen local VBFs, can achieve union rates up to 90% to 100% in appropriately selected patients.

Traditional Bone Grafting in Scaphoid Nonunion

Management of scaphoid nonunion remains challenging despite modern fixation techniques. Nonvascularized bone graft may be used to achieve union in waist and proximal pole fractures with good success rates. Technical aspects, such as adequate debridement and restoration of scaphoid length, and stable fixation are critical in achieving union and functional wrist usage. Rigid fixation can be achieved with compression screws, K-wires, and plate constructs. The surgeon has a choice of various bone graft options including corticocancellous, cancellous, and strut grafts to promote healing and correct the humpback deformity.

Vascularized Medial Femoral Condyle Flap Reconstruction for Osseous Defects of the Hand and Wrist

Vascularized bone flaps from the descending genicular artery system are versatile and effective for the use of recalcitrant nonunions from the tubular bones of the hand to the long bones of the upper extremity. Familiarity with the vascular pedicle, various techniques of harvest and inset, and skin paddle harvest and application are essential for the reconstructive surgeon.

Arthroscopic Bone Grafting and Robot-assisted Fixation for Scaphoid Nonunion

OBJECTIVES

Scaphoid nonunion remains a challenging problem to manage with no general consensus on its treatment recommendations. We propose a novel minimally invasive (MIS) technique of arthroscopic bone grafting (ABG) with robot-assisted fixation for the treatment of scaphoid nonunions.

METHODS

Patients with radiographically proven scaphoid nonunion treated by this novel surgical technique were included. Following arthroscopic debridement and iliac crest bone grafting, the scaphoid was fixed percutaneously using either multiple Kirschner (K)-wires or a headless compression screw using a robotic navigation system.

RESULTS

Six male patients with an average age of 29.2 years were enrolled. Four patients had scaphoid waist fractures, and the other two were proximal pole fractures. During wrist arthroscopy, punctate bleeding of the proximal scaphoid fragment was observed in four out of the six patients. Half of the patients were fixed using a headless compression screw and the other half using multiple K-wires. All the guidewires were placed with a single-attempt using the robotic navigation system. Postoperatively, all the scaphoid fractures had complete radiographic union by 16 weeks. At a mean follow-up of 18.3 months, there were significant improvements in wrist range of motion, grip strength, and patient-rated outcomes. No intraoperative or early postoperative complications were encountered in any of our patients.

CONCLUSION

Arthroscopic bone grafting with robot-assisted fixation is a feasible and promising therapeutic option for scaphoid nonunions, regardless of the vascularity of the proximal pole fragment. This novel technique allows for anatomic restoration of the scaphoid alignment and accurate, targeted placement of implants into the scaphoid nonunion site within a single-attempt using a robotic navigation system.

Treatment of scaphoid nonunion by arthroscopic cancellous bone grafting

INTRODUCTION

In order to avoid Scaphoid Nonunion Advanced Collapse (SNAC) type osteoarthritis, which progressively affects the radial and midcarpal joints, several vascularized and non-vascularized grafting techniques have been described. Over the past decade, there has been growing interest in arthroscopic cancellous bone grafts for scaphoid nonunion. The aim of this novel prospective study was to assess the healing rate of scaphoid grafts under arthroscopy, and the prognostic factors for healing.

MATERIAL AND METHODS

This prospective study was carried out across 10 centers between September 2019 and April 2021, in patients aged 16 to 65. Scaphoid nonunion grafting was performed arthroscopically. Union was assessed on CT scans and displacement correction angles were measured preoperatively and then at 3 and 6months. We assessed mobility, Jamar wrist strength, functional results as per the Patient Related Wrist Score (PRWE) and the Quick Disabilities of the Arm, Shoulder and Hand (Quick DASH) score. Risk factors for nonunion were assessed.

RESULTS

We included 77 patients with a mean age of 24years (18 to 55years) with a mean time between trauma and treatment of nonunion of 34.8months (6 to 180months). The population was represented by 46 manual workers and 20 were smokers. In 42 cases, the nonunion was proximal, in Schernberg zone I or II. At the last follow-up of 12.9months on average (Standard Deviation: 8.7months), union was achieved in 72 patients (93.5%). The average duration of union was 3.4months (Standard Deviation 1.6). Among the 5 patients who did not heal, grafting was performed in addition to the fixation. We did not identify any contributory factors for nonunion.

CONCLUSION

This study demonstrated the effectiveness of arthroscopic treatment of scaphoid nonunion with a union rate at least equivalent to pedicled vascularized grafts. Smoking and delayed treatment were no longer considered unfavorable prognostic factors in the context of arthroscopic treatment.

LEVEL OF EVIDENCE

III.

Postoperative scaphoid alignment, smoking, and avascular necrosis mostly influence union rate after scaphoid reconstruction: Results from a retrospective single center study involving 370 patients

Current literature does not definitely demonstrate the superiority of any particular scaphoid reconstruction method. The primary goal of this retrospective single center study was to evaluate the influence of reconstruction techniques and other factors on the union rate after reconstruction of scaphoid nonunions. In the study, 370 patients with nonunions classified as stable (Mayo 1) or unstable (Mayo 2) depending on carpal alignment were included. Minimal radiological follow-up was 3 months. Bone healing after scaphoid reconstruction was evaluated using computer tomography scans in 294 and radiograms in 76 patients. Univariate and multivariate logistic regressions were applied in the analysis. Eight statistically significant factors that influenced the union rate were fixation method, type of previous operations, number of all operations, number of reconstructions, smoking, postoperative pathological lateral intrascaphoid angle (LISA>45°), avascular necrosis (AVN), and stability of nonunion. Smoking and postoperative LISA>45° significantly reduced the probability of bone fusion by approximately 4.4 and 9.5 times, respectively. Patients with reduced vascularity in the nonunion site had a 5.2 times lower chance of bone fusion. Our multivariate logistic regression model can explain 32% of failures after scaphoid reconstruction, including postoperative LISA>45°, patients' present record of smoking, and reduced vascularity in the nonunion site. However, bone graft type does not impact the union rate in general; however, in case of AVN, the tendency toward higher union rates was observed for medial femoral condyle free flaps when compared to other types of graft (non-vascularized and pedicled bone grafts considered as one group, p = 0.09).

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.

Scaphoid and Carpal Bone Fracture: The Difficult Cases and Approach to Management

Scaphoid and carpal bone fractures are challenging injuries to manage and have significant functional implications. Prompt diagnosis is important and relies on systematic evaluation via history, examination, and imaging. Cross-sectional imaging is often helpful for diagnosis and treatment planning. Treatment for nondisplaced fractures is often closed but these injuries typically require prolonged immobilization and may still result in nonunion or avascular necrosis. Displaced carpal bone fractures, and those associated with carpal instability, typically require open reduction internal fixation.

Arthroscopic versus open cancellous bone grafting for scaphoid delayed/nonunion in adults (SCOPE-OUT): study protocol for a randomized clinical trial

BACKGROUND

Scaphoid non-union results in pain and decreased hand function. Untreated, almost all cases develop degenerative changes. Despite advances in surgical techniques, the treatment is challenging and often results in a long period with a supportive bandage until the union is established. Open, corticocancellous (CC) or cancellous (C) graft reconstruction and internal fixation are often preferred. Arthroscopic assisted reconstruction with C chips and internal fixation provides minimal trauma to the ligament structures, joint capsule, and extrinsic vascularization with similar union rates. Correction of deformity after operative treatment is debated with some studies favouring CC, and others found no difference. No studies have compared time to union and functional outcomes in arthroscopic vs. open C graft reconstruction. We hypothesize that arthroscopic assisted C chips graft reconstruction of scaphoid delayed/non-union provides faster time to union, by at least a mean 3 weeks difference.

METHODS

Single site, prospective, observer-blinded randomized controlled trial. Eighty-eight patients aged 18-68 years with scaphoid delayed/non-union will be randomized, 1:1, to either open iliac crest C graft reconstruction or arthroscopic assisted distal radius C chips graft reconstruction. Patients are stratified for smoking habits, proximal pole involvement and displacement of > / < 2 mm. The primary outcome is time to union, measured with repeated CT scans at 2-week intervals from 6 to 16 weeks postoperatively. Secondary outcomes are Quick Disabilities of the Arm, Shoulder and Hand (Q-DASH), visual analogue scale (VAS), donor site morbidity, union rate, restoration of scaphoid deformity, range of motion, key-pinch, grip strength, EQ5D-5L, patient satisfaction, complications and revision surgery.

DISCUSSION

The results of this study will contribute to the treatment algorithm of scaphoid delayed/non-union and assist hand surgeons and patients in making treatment decisions. Eventually, improving time to union will benefit patients in earlier return to normal daily activity and reduce society costs by shortening sick leave.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05574582. Date first registered: September 30, 2022. Items from the WHO trial registry are found within the protocol.

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.

Double screw versus angular stable plate fixation of scaphoid waist nonunions in combination with intraoperative extracorporeal shockwave therapy (ESWT)

INTRODUCTION

Over the past years, different fixation techniques focused on rotational stability in order to increase stability and stimulate union rates. Additionally, extracorporeal shockwave therapy (ESWT) has gained importance in the treatment of delayed and nonunions. Purpose of this study was to compare the radiological and clinical outcome of two headless compression screws (HCS) and plate fixation in scaphoid nonunions, in combination with intraoperative high energy ESWT.

MATERIALS AND METHODS

Thirty-eight patients with scaphoid nonunions were treated by using a nonvascularized bone graft from the iliac crest and stabilization with either two HCS or a volar angular stable scaphoid plate. All patients received one ESWT session with 3000 impulses and energy flux per pulse of 0.41 mJ/mm² intraoperatively. Clinical assessment included range of motion (ROM), pain according to the Visual Analog Scale (VAS), grip strength, disability of the Arm Shoulder and Hand Score, Patient-Rated Wrist Evaluation Score, Michigan Hand Outcomes Questionnaire and modified Green O'Brien (Mayo) Wrist Score. To confirm union, a CT scan of the wrist was performed.

RESULTS

Thirty-two patients returned for clinical and radiological examination. Out of these, 29 (91%) showed bony union. All patients treated with two HCS compared to 16 out of 19 (84%) patients treated by plate showed bony union on the CT scans. The difference was not statistically significant. However, at a mean follow-up interval of 34 months, no significant differences could be found in ROM, pain, grip strength and patient-reported outcome measurements between the two HCS and plate group. Height-to-length ratio and capitolunate angle improved significantly in both groups compared to preoperative.

CONCLUSIONS

Scaphoid nonunion stabilization by using two HCS or angular stable volar plate fixation and intraoperative ESWT results in comparable high union rates and good functional outcome. Due to the higher rate for a secondary intervention (plate removal), HCS might be preferable as first choice, whereas the scaphoid plate fixation should be reserved for recalcitrant (substantial bone loss, humpback deformity or failed prior surgical intervention) scaphoid nonunions.

A Review of the Use of 3D Printing Technology in Treatment of Scaphoid Fractures

Background: Three-dimensional (3D) printing technology is increasingly commercially viable for pre-surgical planning, intraoperative templating, jig creation and customised implant manufacture. The challenging nature of scaphoid fracture and nonunion surgery make it an obvious target. The aim of this review is to determine the use of 3D printed technologies in the treatment of scaphoid fractures. Methods: This is a review of the Medline, Embase and Cochrane Library databases examining studies aimed at therapeutic use of 3D printing, also known as rapid prototyping or additive technology, in the treatment of scaphoid fractures. All studies published up to and including November 2020 were included in the search. Relevant data extracted included modality of use (as template/model/guide/prosthesis), operative time, accuracy of reduction, radiation exposure, follow-up duration, time to union, complications and study quality. Results: A total of 649 articles were identified, of which 12 met the full inclusion criteria. Analysis of the articles showed that 3D printing techniques can be utilised in myriad ways to aid planning and delivery of scaphoid surgery. Percutaneous guides for Kirschner-wire (K-wire) fixation of non-displaced fractures can be created; custom guides can be printed to aid reduction of displaced or non-united fractures; patient-specific total prostheses may recreate near-normal carpal biomechanics and a simple model may help graft harvesting and positioning. Conclusions: This review found that the use of 3D printed patient-specific models and templates in scaphoid surgery can improve accuracy and speed, and reduce radiation exposure. 3D printed prostheses may also restore near-normal carpal biomechanics without burning bridges for potential future procedures. Level of Evidence: Level III (Therapeutic).

Perfusion of the proximal scaphoid pole: correlation between preoperative ge-MRI and intraoperative findings

BACKGROUND

Gadolinium enhanced MRI (ge-MRI) is considered as gold standard for perfusion evaluation in case of scaphoid nonunion (SNU). However, its clinical value and specificity is still not clearly evaluated. This study compares preoperative ge-MRI-based perfusion assessment and intraoperative proximal pole (PP) perfusion after scaphoid reconstruction by vascularized bone grafts. In addition, the postoperative osseous consolidation (OC) was correlated to intraoperative perfusion findings.

METHODS

Between 08/2010 and 01/2020, 60 of 271 patients with scaphoid nonunion received a vascularized radius bone graft for reconstruction. Medical reports were checked for intra-op perfusion findings. Consolidation rate was assessed at mean follow-up of 3 months by CT evaluation. In 50 cases (83.2%), complete medical and radiological history could be obtained. Preoperative ge-MRI was reevaluated by a blinded radiologist for advanced analysis of sensitivity and specificity.

RESULTS

Preoperative ge-MRI (initial finding, IF) showed 23 avascular, 20 malperfused, and seven vital PP. Blinded radiological follow-up (second finding, SF) revealed 14 avascular, 28 malperfused, and 8 vital PP, with a concordance of 65.3% (n = 35). After correlation with the intra-op findings, a specificity of preoperative ge-MRI of 76.5% (IF) and 88.2 (SF), respectively, was revealed for exclusion of avitality. For detection of malperfusion, there was a sensitivity of 92.7% (IF) and 85.4% (SF), respectively. Complete OC was seen 12 weeks postoperatively in 37 (73.5%), partial OC in 9 (18.3%), and nonunion in 4 cases (8.2%) on CT-scans. Of the 41 malperfused/avascular PP, 31 (75.6%) progressed to complete and 6 (14.6%) to partial (at least 2 adjacent CT-layers of 2 mm) OC, with 4 nonunions.

CONCLUSION

The sensitivity and specificity of ge-MRI for detection/ exclusion of malperfusion/avitality of the PP was lower than expected. Therewith, the intraoperative assessment of PP perfusion regains a high value in decision-making for the appropriate graft. We recommend preservation of the dorsal radial vascular plexus initially until the vascularity of the proximal pole has been estimated. Patient education for all contingencies and retraction options should be obtained.

Vascularised versus non-vascularised bone graft for scaphoid nonunion: Meta-analysis of randomised controlled trials and comparative studies

Background

Numerous studies have investigated surgical techniques for vascularised bone graft (VBG) for scaphoid nonunion; however, their efficacies remain unclear. Thus, to estimate the union rate of VBG for scaphoid nonunion, we performed a meta-analysis of randomised controlled trials (RCTs) and comparative studies.

Methods

A systematic search was conducted using PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials. The search formula was as follows: ((scaphoid nonunion) OR (scaphoid pseudarthrosis)) AND (bone graft). Only RCTs were used in the primary analysis, and comparative studies, including RCTs, in the secondary analysis. The primary outcome was nonunion rate. We compared the outcome between VBG and non-vascularised bone graft (NVBG), pedicled VBG and NVBG, and free VBG and NVBG.

Results

This study included a total of 4 RCTs (263 patients) and 12 observational studies (1411 patients). In the meta-analyses of both RCTs only and RCTs and other comparative studies, no significant difference in nonunion rate was found between VBG and NVBG (summary odds ratio [OR], 0.54; 95% confidence interval [CI], 0.19-1.52 and summary OR, 0.71; 95% CI, 0.45-1.12), respectively. The nonunion rates of pedicled VBG, free VBG, and NVBG were 15.0%, 10.2%, and 17.8%, respectively, and no significant difference was found.

Conclusions

Our results indicated that the postoperative union rate in NVBG is similar to that in VBG; thus, NVBG could be the first choice of treatment for scaphoid nonunion.

Functional Scaphoid Pseudarthrosis. Two Cases with Long-term Follow-up after Closed Wedge Osteotomy of the Distal Radius

Introduction

Closed wedge osteotomy of the distal radius represents a treatment option for the advanced scaphoid pseudarthrosis. Few authors have reported good results with many of the cases achieving union of the scaphoid. The aim of this study is to inform about the functional long-term outcome of two patients in whom bone union was not achieved after this procedure.

Case Report

In this article, we present two patients, one with 5 and one with 40 years of follow-up who were treated with closed wedge osteotomy of the distal radius due to advanced scaphoid nonunion. We evaluated the functional outcome which was excellent and in addition radial translocation of the carpus was found as it was compared the anteroposterior radiographs before surgery and at the end of the follow-up period.

Conclusion

Closed wedge osteotomy of the radius is an extra articular procedure that can cause radial translocation of the wrist and change its biomechanics, while the functional outcome does not depend on whether fracture healing is achieved.

[Arthroscopic reconstruction of scaphoid nonunions]

OBJECTIVE

Minimally invasive arthroscopically assisted reconstruction of scaphoid nonunions.

INDICATIONS

Delayed union or nonunion of the scaphoid with sclerosis and with indication for bone transplantation. Limited arthritic changes at the radial styloid.

CONTRAINDICATIONS

Severe humpback deformity with dorsal intercalated segment instability. Midcarpal arthritic changes.

SURGICAL TECHNIQUE

Supine position with the forearm upright and in neutral position, the elbow flexed by 90°, axial traction of 3 to 4 kg. Standard wrist arthroscopy via the 3-4 and the 4-5 portal and the midcarpal joint via the radial and ulnar portal, respectively, with sodium chloride as arthroscopy medium. Change of the optic to the ulnar midcarpal portal and opening of the nonunion with an elevator via the radial midcarpal portal. Resection of the sclerosis with a 3.0 mm burr while irrigating the joint. Harvesting of cancellous bone via the second extensor compartment. On the hand table, closed reduction by joy-stick K‑wires if needed and insertion of K‑wires for the scaphoid screw. Insertion of the screw without entering of the distal thread into the bone. Arthroscopic insertion of the bone transplant by a blunt drill sleeve via the radial portal with steady compression by the obturator. Complete insertion of the screw under arthroscopic control of the compression of the nonunion space with arthroscopic control of stability with the probe.

POSTOPERATIVE MANAGEMENT

Six weeks forearm cast including the thumb metacarpophalangeal joint, radiographic control and non-load bearing movements for two more weeks, CT scan in the oblique sagittal plane after 8 weeks, and increase of load, as well as physiotherapy on demand depending on the radiographic results.

RESULTS

To date, 17 patients with a mean age of the nonunion of 18 months were treated. In 14 patients, bony union was achieved after 8 weeks. In one patient, an extraosseous screw placement was corrected. In another patient with extraosseous screw placement, persisting nonunion was treated with an angular stable plate. One scaphoid demonstrated an asymptomatic tight nonunion after 14 months, while one scaphoid with sclerosis of the proximal pole did not heal.

Long-term outcomes of the four-corner fusion of the wrist: A systematic review

BACKGROUND

Four-corner fusion (4CF) is a motion sparing salvage procedure that is used to treat osteoarthritis secondary to advanced scapholunate collapse or longstanding scaphoid nonunion advanced collapse. Little is known about the long-term survivorship and outcomes of 4CF.

AIM

To report on clinical and functional long-term outcomes as well as conversion rates to total wrist fusion or arthroplasty.

METHODS

The systematic review protocol was registered in the international prospective register of systematic reviews (PROSPERO) and followed the PRISMA guidelines. Original articles were screened using four different databases. Studies with a minimum Level IV of evidence that reported on long-term outcome after 4CF with a minimum follow-up of 5 years were included. Quality assessment was performed using the Methodological Index for Non-Randomized Studies criteria.

RESULTS

A total of 11 studies including 436 wrists with a mean follow-up of 11 ± 4 years (range: 6-18 years) was included. Quality assessment according to Methodological Index for Non-Randomized Studies criteria tool averaged 69% ± 11% (range: 50%-87%). Fusion rate could be extracted from 9/11 studies and averaged 91%. Patient-reported outcomes were extracted at last follow-up from 8 studies with an average visual analog scale of 1 ± 1 (range: 0-2) and across 9 studies with an average Disabilities of the Arm, Shoulder and Hand score of 21 ± 8 (range: 8-37). At last follow-up, the cumulative conversion rate to total wrist fusion averaged 6%. There were no conversions to total wrist arthroplasty.

CONCLUSION

The 4CF of the wrist is a reliable surgical technique, capable of achieving a good long-term patient satisfaction and survivorship with low rates of conversion to total wrist fusion.

Dorsal capsular-based vascularized distal radius graft for proximal pole scaphoid nonunion with avascular necrosis

BACKGROUND

Scaphoid nonunion involving the proximal pole with the presence of avascular necrosis is difficult to reconstruct. We aimed to determine the efficacy of surgical treatment of proximal pole scaphoid nonunion with avascular necrosis using a dorsal capsular-based vascularized distal radius graft.

METHODS

Between 2000 and 2018, 64 patients with established proximal pole scaphoid nonunion with avascular necrosis were treated using a dorsal capsular-based vascularized distal radius graft. This graft was harvested from the dorsal aspect of the distal radius with its dorsal wrist capsule attachment. Fixation of the scaphoid nonunion was performed with a small cannulated screw, followed by insertion of the vascularized graft into the dorsal trough at the scaphoid nonunion site. In the last 47 patients of this series, a micro suture anchor was placed into the scaphoid to augment graft fixation.

RESULTS

Union rate was 86% (55 of 64 scaphoid nonunions with avascular necrosis) at a mean time of 12 weeks. Persistent non-union was noted in eight patients and fibrous union in one patient. No patients developed donor site morbidity. No graft dislodgment was noted. There was significant improvement of the wrist functional outcomes at the final follow up.

CONCLUSIONS

The dorsal capsular-based vascularized distal radius graft is a safe and effective treatment in patients with scaphoid nonunion with avascular necrosis of the proximal pole. This pedicle vascularized bone graft is derived from a location that can easily reach the proximal third of the scaphoid avoiding microsurgical dissection or anastomosis.

A Comparison of Non-vascularized Bone Grafting and Internal Fixation in the Treatment of Unstable Scaphoid Waist Nonunion

Background: When nonunion of scaphoid waist is treated with non-vascularized bone grafting with internal fixation, bony union would be affected not only type of bone graft but also fixation method. Thus, we attempted to investigate whether the bony union depends on how surgeons combine bone grafting and internal fixation. Methods: We treated 38 consecutive patients with unstable nonunion of scaphoid waist. The patients were treated with one of three types of non-vascularized bone grafting and internal fixation by random sampling, regardless of the configuration of the nonunion; cortico-cancellous bone grafting with Kirschner wire (K-wire) fixation group (12 cases), cortico-cancellous bone grafting with headless compression screw fixation group (13 cases) and cancellous bone grafting with K-wire fixation group (13 cases). We compared "union rate" and "time to union" between groups with statistical analysis. We described clinical features of "failure to union" cases. Results: The mean time to union of cancellous bone grafting with K-wire fixation group was significantly shorter than those of other groups. There was also significant difference in mean time to union between cortico-cancellous bone grafting with K-wire fixation group and cancellous bone grafting with K-wire fixation group (when the type of bone grafting was different). All the "failure to union" cases were sclerotic (Herbert type D2) nonunion treated by cortico-cancellous bone grafting. Conclusions: When treating unstable nonunion of scaphoid waist with non-vascularized bone grafting with internal fixation, cancellous bone grafting with K-wire fixation seems to be advantageous in terms of mean time to union. It seems that both bone grafting and fixation method affected "mean time to union" but the type of bone grafting was more influential in achieving union. The failure to union might be frequent in case of Herbert type D2 nonunion combined with cortico-cancellous bone grafting.

Volar rerouting of the 1,2 intercompartmental supraretinacular artery vascularized bone graft for middle and distal scaphoid nonunions

BACKGROUND

The bone graft vascularized by the 1,2 intercompartmental supraretinacular artery (1,2 ICSRA) placed on the scaphoid by a dorsal approach is a technique used to treat scaphoid nonunions with avascular necrosis of the proximal pole and without significant bone loss or carpus collapse. We present the results of patients treated with a volar rerouting of the 1,2 ICSRA graft under the tendons of the first extensor compartment to treat more distal scaphoid nonunions than the proximal pole. The aim of this study was to assess the clinical and radiological outcomes of patients operated with this technique with the hypothesis that it would allow to treat more distal nonunions than those of the proximal pole.

PATIENTS AND METHODS

This retrospective study involved patients treated by a volar rerouting of the 1,2 ICSRA graft for nonunions of the middle and distal thirds of the scaphoid. Assessments included clinical outcomes and radiological bone consolidation. QuickDASH and Mayo Wrist scores were computed. Range of motion and grip strength were evaluated for both the operated and the contralateral sides.

RESULTS

Nineteen patients were followed-up for 33 months (range: 6-75). Mean postoperative QuickDASH score was 10 (range: 0-45), and mean Mayo wrist score was 85 (range: 50-100). Flexion and extension, ulnar and radial deviations were statistically different between the affected and healthy sides (p<0,05). Consolidation was achieved in 17 patients (89%).

DISCUSSION

This technical modification allowed good functional outcomes and scaphoid consolidation. It expands the classic indications of the vascularized 1,2 ICSRA bone graft to more distal nonunions than the proximal pole.

LEVEL OF EVIDENCE

IV.

Vascularized pisiform graft for the treatment of scaphoid nonunion: An anatomical study

Scaphoid fracture can evolve into scaphoid nonunion leading to wrist arthritis. Vascularized bone flaps used to treat scaphoid nonunion are supplied by delicate, small, or short arteries that are not always reliable. The pisiform bone has never been considered as a possible treatment of scaphoid nonunion since the traditionally harvested pedicle is too short. This study aimed to characterize the vascularization of the pisiform with the goal of developing a method of harvesting it with a longer pedicle that can be used as a graft to treat scaphoid nonunion. A cadaver study on 30 upper limbs was done in two parts: firstly, we dissected 20 cadaver specimens and documented the pisiform's vascularization (size, length, and articular surface) as well as anatomical characteristics of the dorsal ulnar artery; secondly, we used 10 cadaver specimens to study an experimental surgical procedure in which a vascularized pisiform graft is used to treat an artificially created nonunion and confirm its feasibility. The pisiform artery originated from the dorsal ulnar artery in all 20 dissections. Its average length of 4.036cm could be increased by 11% by ligating the upstream collateral branches from the dorsal ulnar artery. The pedicled vascularized pisiform flap was grafted to the scaphoid in 10 experimental procedures performed on fresh cadavers. The vascularized pisiform graft consists of a reliable vascular pedicle and well vascularized multi-cortical bone with a cartilaginous surface. However, more studies are needed to confirm the feasibility of this flap as an alternative for treating unstable scaphoid nonunion.

Correction of humpback and DISI deformities by vascularized bone grafting in patients with scaphoid nonunion

Introduction: Although vascularized bone grafting (VBG) using 1, 2 intercompartmental supraretinacular artery (1, 2 ICSRA) is effective for scaphoid nonunion, dorsal intercalated segment instability (DISI) deformity persists even after correction of humpback deformity (HD). The purpose of this retrospective study was to evaluate the correction of HD and DISI deformity after 1, 2 ICSRA VBG for scaphoid nonunion. Methods: We treated 18 patients (mean age: 25.8, 16 males and 2 females) with scaphoid nonunion using a 1, 2-ICSRA VBG between January 2010 and December 2018. The average time from injury to surgery was 20.0 (3–120) months. The nonunions were located at the waist in all patients. The correction of HD and DISI deformity was investigated on the preoperative images and images at the last examination. Results: In all patients, the correction of HD was positively correlated with that of DISI deformity. Moreover, we focused on the time from injury to surgery and evaluated changes in HD and DISI deformity according to the time to surgery. As a result, changes in HD and DISI deformity were positively correlated in patients with a shorter time to surgery but were not correlated when the time to surgery exceeded 5 months. Conclusions: These results suggest that DISI deformity can be corrected by correcting HD when the time from injury to surgery is short, but that correction is difficult if the time to surgery is prolonged.

Proximal row carpectomy combined with primary flexor pollicis longus tenorrhaphy: An effective treatment alternative for a rare case of flexor pollicis longus rupture due to scaphoid nonunion advanced collapse

This study describes a case of flexor pollicis longus rupture resulting from long-term scaphoid nonunion advanced collapse. The tendon rupture mechanism was attrition due to sharp bone protuberances from the scaphoid in the carpal tunnel. Although this extremely rare complication has already been reported in the literature, our study is original in showing that proximal row carpectomy with consequent wrist shortening allowed primary tendon repair without transferring the flexor digitorum superficialis tendon of the ring finger or grafting the palmaris longus tendon, which besides using two-level suturing, interposes a non-vascularized tissue.

Mid-term outcome of volar plate fixation for scaphoid nonunion

AIMS

Fixation of scaphoid nonunion with a volar locking plate and cancellous bone grafting has been shown to be a successful technique in small series. Few mid- or long-term follow-up studies have been reported. The aim of this study was to report the mid-term radiological and functional outcome of plate fixation for scaphoid nonunion.

METHODS

Patients with a scaphoid nonunion were prospectively enrolled and treated with open reduction using a volar approach, debridement of the nonunion, and fixation using a locking plate and cancellous bone grafting, from the ipsilateral iliac crest. Follow-up included examination, functional assessment using the patient-rated wrist/hand evaluation (PRWHE), and multiplanar reformation CT scans at three-month intervals until union was confirmed.

RESULTS

A total of 49 patients with a mean age of 31 years (16 to 74) and a mean duration of nonunion of 3.6 years (0.4 to 16) were included. Postoperatively, the nonunion healed in 47 patients (96%) as shown on CT scans. The mean time to union was 4.2 months (3 to 12). Due to impingement of the plate on the volar rim of the radius and functional limitation, the hardware was removed in 18 patients. At a median follow-up of 38 months in 34 patients, the mean active range of motion (ROM) improved significantly from 89° to 124° (SD 44°; p = 0.003). The mean grip strength improved significantly from 52% to 79% (SD 28%; p < 0.001) of the contralateral side. The mean PRWHE score improved significantly from 66 to 17 points (SD 25; p < 0.001).

CONCLUSION

Locking plate fixation supplemented with autologous cancellous bone grafting is a successful form of treatment for scaphoid nonunion. Functional outcomes improve with the passage of time, and mid-term results are excellent with a significant improvement in ROM, grip strength, and functional outcome as measured by the PRWHE. Cite this article: Bone Joint J 2020;102-B(12):1697-1702.

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.

Wrist function recovery course in patients with scaphoid nonunion treated with combined volar bone grafting and a dorsal antegrade headless screw

Background

Surgical treatment is necessary for scaphoid nonunion. Open surgery with a combined volar and dorsal approach is thought to have poor functional outcomes and a prolonged recovery course. However, the detailed recovery course for this approach is rarely reported. The aim of this study was to investigate the recovery course and radiographic outcome for patients with scaphoid nonunion who underwent a combined volar bone grafting and dorsal antegrade headless screw approach.

Material and methods

Eighteen patients with scaphoid nonunion who underwent combined volar bone grafting and dorsal antegrade headless screw fixation were enrolled in this retrospective study. Preoperative and serial postoperative wrist functional and radiographic outcomes were collected and analysed.

Results

All 18 patients achieved bone union at a mean time of 14.3 weeks. Compared to the preoperative status, the grip strength, wrist motion arc, and Mayo Wrist score were improved significantly 6 months after surgery, whilst the Disabilities of the Arm, Shoulder, and Hand (DASH) score did not recover until 12 months after surgery. Significant improvements were found in all scaphoid radiographic parameters.

Conclusion

The surgical outcomes for scaphoid nonunion treated with a combined volar bone grafting and dorsal antegrade headless screw achieved a high union rate, with great wrist functional and radiographic outcomes. The earliest recovered wrist functional parameters were grip strength, motion arc, Mayo Wrist score and finally the DASH score at postoperative 6 months and 12 months, respectively.

3D printing-assisted percutaneous fixation makes the surgery for scaphoid nonunion more accurate and less invasive

Purpose

The study was to explore whether the 3-dimensional printing guiding plate system could facilitate the modified procedure for arthroscopic treatment of nondisplaced scaphoid nonunion.

Methods

Patients, diagnosed with scaphoid nonunion without displacement, were randomly assigned into two groups. In Group A, the 3-dimensional printing guiding plate system was used for guiding fixation during the surgery. In Group B, fixation was performed with intra-operative fluoroscopy. The bone operation time was recorded during the surgery. The patients were evaluated before surgery and followed-up after six post-operative months, including motion ratio, strength ratio, Visual Analogue Scale, modified Mayo Scores, Patient Rated Wrist Evaluation scores, plain radiography and CT scan.

Results

Sixteen patients were recruited for the study. The average bone operation time in Group A was statistically shorter than that in Group B.

Conclusions

3-dimensional printing technique-assisted arthroscopic bone graft and fixation of scaphoid nonunion constitute an effective and accurate clinical treatment option.

The translational potential of this article

The concept and technique of 3D printing assisted percutaneous fixation introduced in this paper have the potential to be applied in a variety of operations requiring accurate percutaneous fixation, especially for the joint injuries.

Pedicled vascularized bone grafts compared with xenografts in the treatment of scaphoid nonunion

INTRODUCTION

Fractures of the scaphoid account for 60-70% of all wrist bone fractures. The results of treatment in terms of bone healing vary depending on the type and location of the fracture, the time elapsed since the injury, the type of surgical treatment. Nonunion occurs in 5-15% of the cases on average. The purpose of this paper is to compare the surgical techniques and results of treating scaphoid nonunion (SNU) with osteoplastic xenografts of bovine origin or a vascularized autograft of the distal part of the dorsal radius.

METHODS

We compare two groups of patients with symptomatic SNU, treated surgically with either a vascularized graft (n = 15) or a xenograft of bovine origin (n = 15). In the presurgical stage, the demographic characteristics of the patients, the time elapsed between injury and surgery, and classification of the injury (Schonberg, Herbert-Fisher, and Geissler-Slade) were recorded. One year following surgery, bone healing, total duration of the treatment, complications, the Mayo wrist score, and answers to the DASH questionnaire were analyzed.

RESULTS

No statistically significant differences between the two groups of patients were observed for bone healing (86.7% vs 80%) or functional results. A highly significant difference was observed with respect to duration of the surgical intervention in favor of xenografts.

CONCLUSION

The xenograft method is simple and relatively acceptable, providing good results in terms of healing and functionality.

How Long Should We Immobilize the Wrist after Vascularized Bone Grafting for the Treatment of Scaphoid Nonunion?

Background: Although vascularized bone grafting can effectively treat scaphoid nonunion, the optimal duration of the immobilization period after bone grafting is unclear. Therefore, we aimed to examine the difference in the union rate and range of motion between short and long immobilization periods and infer the optimal post-immobilization period after pedicled vascularized bone grafting for scaphoid nonunion treatment. Methods: A total of 23 wrists (21 men and 1 woman) with scaphoid nonunion treated using an intercompartmental supraretinacular artery pedicled vascularized bone graft were analyzed. We examined the difference in the union rate and range of motion between patients immobilized for less than 49 days (short immobilization group) and those immobilized for more than 49 days (long immobilization group). The range of motion of the wrist joint was measured before and after surgery. Patient outcomes were also assessed. Results: The overall union rate was 95.6%. A significant difference was found in postoperative extension and flexion between the two groups, but not in terms of the functional outcome. If the intraoperative fixation is solid, intraoperative proximal pole bleeding is confirmed, and the follow-up radiograph shows a normal healing process, we propose immobilization of the wrist for ≤ 7 weeks. Conclusions: The immobilization duration should depend on the solidity of intraoperative fixation and a satisfactory appearance on follow-up radiography: absence of a gap at the graft interface, surrounding lucency, or movement of the implant and displacement of the graft. If there are no signs of graft failure and fixation is solid, immobilization of the wrist for 7 weeks or less is recommended.

Kirschner wire versus Herbert screw fixation for the treatment of unstable scaphoid waist fracture nonunion using corticocancellous iliac bone graft: randomized clinical trial

PURPOSE

The study compared the impact of the Kirschner wires versus Herbert screw fixation on the rate of union, time to union, correction of deformity, and clinical outcome in adults with unstable scaphoid waist fracture nonunions without avascular necrosis.

METHODS

We prospectively randomized 122 patients to undergo corticocancellous iliac bone grafting and internal fixation either with multiple Kirschner wires or Herbert screw. Radiographs, clinical outcome measures (pain, range of motion, and grip strength), and the Quick DASH score were taken pre- and post-operatively.

RESULTS

The rate of the scaphoid union in the Kirschner wire group was 91% versus 88% in the Herbert group. No difference was detected between the two groups with respect to the time to union, deformity correction, pain analysis, range of motion, grip strength, return to work, and complications.

CONCLUSION

Using of multiple Kirschner wires as a fixation method for unstable scaphoid waist fracture nonunion that was treated by open reduction and corticocancellous iliac bone grafting had a shorter operative time and lower cost as compared with the Herbert screw fixation. Herbert screw fixation was technically more demanding in terms of technique than K-wires. However, because of easy application of Kirschner wires, and low cost, especially in developing countries, it may be a good alternative to Herbert screw.

Acute Scaphoid Waist Fracture in the Athlete

Scaphoid fractures are the most common carpal fracture and the most challenging. Although appropriately managing acute scaphoid waist fractures is a priority, it also is of primary importance to make a diagnosis acutely. Scaphoid waist fractures can occur with low-energy trauma and lead to mild symptoms. A tendency to minimize symptoms and low level of initial disability lead to delay in diagnosis. Displaced scaphoid fractures require operative intervention uniformly. Although nondisplaced fractures can heal with nonoperative treatment, management of these injuries is affected by patient demands. In high-level athletes, operative treatment of nondisplaced injuries may lead to earlier return to sport.

Revision surgery after vascularized or non-vascularized scaphoid nonunion repair: A national population study

HYPOTHESIS

We aimed (1) to discover the prevalence of vascularized bone grafting in the treatment of scaphoid nonunion and (2) to compare healing using vascularized bone grafting versus standard non-vascularized techniques. Secondarily, we sought to compare resource utilization between procedures and identify factors that may be associated with nonunion repair failure. We hypothesized that, despite being less common, vascularized bone grafts have greater success than non-vascularized bone grafting surgeries.

METHODS

We performed a large population analysis using the Truven MarketScan databases to identify patients from 2009 to 2017 with a diagnosis of a scaphoid nonunion undergoing repair surgery with and without the insertion of a pedicled or free vascularized bone graft. We defined any subsequent scaphoid or wrist surgery within 12 months after surgery as surgery failure. We compared success rates and post-operative resource utilization using Chi-squared tests.

RESULTS

Of 4177 eligible patients, 358 underwent nonunion repair with vascularized bone graft and 3819 patients received non-vascularized bone grafting. The failure rate requiring revision surgery was 5.0% in vascularized repair, versus 6.1% for non-vascularized surgery. Age and comorbidities did not affect bone graft type. Areas with higher median household incomes had more vascularized repairs. Vascularized bone graft patients received significantly more therapy and imaging after surgery.

CONCLUSIONS

Most scaphoid nonunion repairs are performed without vascularize bone grafting. Typical nonunions may not justify the increased time and technical demands of vascularized bone grafting, and traditional repair should remain first line treatment for scaphoid nonunions without additional risk factors. Further studies to elucidate which fractures benefit most from vascularized grafting are needed.

Scaphoid nonunions in adolescents: Treatment with vascularized bone grafts

INTRODUCTION

Scaphoid nonunions (SN) are rare in adolescents. The use of vascularized bone grafts (VBG) from the distal radius as an alternative to conventional grafting for the treatment of established SN in adolescents is described.

PATIENTS AND METHODS

The technique was applied in 13 patients with symptomatic SN resulting from fractures. All patients were male with average age of 16.5 years (15-17.5). The average period from injury to surgery was 8.3 months (4-13). Patients underwent vascularized bone grafting and internal fixation with K-wires. In 6 patients with proximal pole nonunion a VBG from the dorsal distal radius was used, and in 7 with a waist nonunion a VBG from the palmar distal radius was used. The valuation was clinical (grip strength, range of motion, VAS pain score, DASH) and radiographic. The time to return to activity was also recorded.

RESULTS

The mean follow-up was 9.8 years (range, 4-16). The union rate was 100% (11/11 cases). Union was achieved in a mean period of 7.2 weeks (range, 6-10), without growth disturbance or other complications from the epiphyseal plate of the distal radius. The range of motion and grip strength was 89% and 92% of the contralateral respectively. The mean postoperative DASH score was 8 and the VAS score was 1. All patients returned to daily activities and sports in a mean period of 4.5 months.

CONCLUSIONS

The use of VBG from the distal radius provided a permanent solution in the rare case of SN in adolescents, without donor site morbidity or epiphyseal plate disturbance. The deformity and carpal height were corrected resulting in painless motion and grip strength.

Carpal kinematic changes after scaphoid nonunion: an in vivo study with four-dimensional CT imaging

The aim was to evaluate if motion between the scaphoid bone fragments is related to the position of the fracture line and if a scaphoid nonunion results in the uncoupling of the proximal and distal carpal row during wrist motion. The influence of dorsal intercalated segment instability on interfragmentary motion was also analysed. In this study, 12 patients were included with unilateral scaphoid nonunion. Four-dimensional computerized tomography was used to analyse flexion-extension and radioulnar deviation motion of both wrists. We found that an increased instability of the scaphoid fragments is associated with the presence of dorsal intercalated segment instability and is not dependent on the position of the fracture line relative to the scaphoid apex. Additionally, a scaphoid nonunion results in an uncoupling of the carpal rows.

Does Anyone Need a Vascularized Graft?

Many hand surgeons argue that vascularized bone grafting is indicated in proximal pole avascular necrosis, prior failed surgery, or long-standing scaphoid nonunion. However, the available evidence does not support improved treatment outcomes for vascularized bone grafting rather than traditional nonvascularized techniques. This article addresses the available evidence and examines the role of vascularized bone grafting in scaphoid nonunion treatment. It also identifies important factors that influence healing, clarifies the decision-making algorithm, and proposes areas for further research.

The Author's Technique for the Management of Unstable Scaphoid Nonunions: Tips and Tricks

This article presents historical aspects, rationale, indications, planning, and execution of anterior interpositional bone grafting technique for unstable scaphoid nonunions. The author's original technique considers four points: (1) preoperative planning based on comparative anteroposterior radiographs in maximal ulnar deviation was used to calculate resection zone, size of the graft, and scaphoid length; (2) a volar approach was used; (3) an iliac crest wedge-shaped corticocancellous graft was interposed; and (4) Kirschner wires were inserted for fixation. Contemporary refinements of the technique including a modification to treat nonunions with failed previous screw fixation with tricks and hints and results are shown.

The Use of the Proximal Hamate as an Autograft for Proximal Pole Scaphoid Fractures: Clinical Outcomes and Biomechanical Implications

Scaphoid proximal pole fractures remain a surgical challenge because of high propensity for nonunion, osteonecrosis, and ultimately carpal collapse. Options for management of nonsalvageable proximal pole fractures include non-vascularized bone grafts, vascularized pedicled bone grafts, free vascularized bone flaps, and rib cartilage grafts. The proximal pole of the hamate can also serve as a replacement arthroplasty in the setting of proximal pole scaphoid nonunions with collapse, bone loss, and/or osteonecrosis. This novel graft addresses shortcomings of other graft choices by providing a local structural autograft solution with minimal donor site morbidity, correcting carpal collapse, reconstructing the scapholunate ligament, and mitigating the need for microvascular anastomosis.

The Role of Vascularized Bone Grafting in Scaphoid Nonunion

Management of scaphoid nonunions requires thoughtful preoperative and intraoperative consideration to evaluate for scaphoid flexion or humpback deformity, carpal collapse, and proximal pole vascularity. Most scaphoid nonunions do not require vascularized bone grafts; however, in the setting of avascular necrosis of the proximal pole, vascularized bone grafts should be used to optimize union rates. In addition, scaphoid geometry and carpal stability must be restored to enhance functional outcomes.

Volar Radius Vascularized Bone Flaps for the Treatment of Scaphoid Nonunion

Vascularized bone flaps (VBFs) improve union rates for scaphoid nonunions compared with nonvascularized grafts. Volar VBFs are indicated in cases of scaphoid nonunion with avascular necrosis and/or humpback deformity. Four volar VBFs are described in this article. The volar carpal artery and pronator quadratus VBFs are most commonly used. The pisiform VBF can be used for replacement of the proximal pole of the scaphoid; it is covered by articular cartilage. The ulna VBF has greater donor morbidity; the ulnar artery is harvested and a palpable donor site deformity results.

Nickel-titanium arched shape-memory alloy connector combined with bone grafting in the treatment of scaphoid nonunion

PURPOSE

To summarize the techniques and clinical effectiveness in treating scaphoid nonunion with nickel-titanium (Ni-Ti) arched shape-memory alloy connector in combination with autologous iliac bone grafts.

METHODS

This study retrospectively analyzed 18 scaphoid nonunion cases treated with arched connectors with autologous iliac bone grafts. Based on scaphoid nonunion, 2 cases were classified as type II (fibrous union), 4 cases as type III (mild sclerotic union), 6 cases as type IV (moderate resorption and sclerosis), 5 cases as type V (severe bone resorption and sclerosis), and 1 case as type VI (pseudarthrosis formation). At the first 4, 8 and 12 weeks after the surgery, wrist anteroposterior, lateral X-ray were obtained, respectively, to evaluate bone healing. Patients who had not yet reached the standard of healing at 12 weeks after surgery would continue to receive additional appointments for follow-up visits, such as 14 weeks, 16 weeks, 18 weeks after surgery, until their imaging studies had achieved satisfactory bone healing. Clinical effectiveness was evaluated comprehensively, based on bone union time, Mayo wrist score, and visual analog pain score.

RESULTS

All 18 patients achieved satisfactory reduction and fixation with a mean union time of 4.2 months. Preoperative Mayo wrist score averaged 57.4 and average final postoperative follow-up was 91.4. On the other hand, mean preoperative VAS score was 6.8, and final postoperative follow-up average was 1.6. Mayo wrist score of the overall treatment effectiveness was excellent (90-100) in 12 cases, good (80-90) in 5 cases, and acceptable (60-80) in 1 case with zero poor (below 60) cases observed. Statistical analysis suggested that a statistically significant improvement in fracture healing, wrist function recovery and visual analog pain after surgery when compared to the scores of the patients before surgery.

CONCLUSION

Using Ni-Ti arched shape-memory alloy connector in combination with autologous bone grafting provided a new modality to treat scaphoid nonunions in a less traumatic, convenient to operate and satisfactory manner in treatment outcomes, and thus is worthy of further application.

Scapho-Capitate Ratio for Estimation of Scaphoid Length

Background: The failure of scaphoid reconstruction by restoring both length and shape may lead to carpal mal-alignment and progressive degenerative arthritis. The aim of our study is to find a reliable method to find out the scaphoid length without measuring the contralateral scaphoid. Methods: Three X-ray wrist views were collected for 51 patients without any signs suggesting any hand and wrist fractures. The scaphoid, capitate and 3^rd metacarpal bone axes lengths and carpal height were measured by 4 hand surgeons separately. Results: The scapho-capitate ratio was 1.1 ± 0.084, 1.01 ± 0.084 and 0.92 ± 0.109 for lateral, postero-anterior with ulnar deviation and postero-anterior view respectively. The ulnar deviation view had the highest reliability. Conclusions: Scapho-capitate ratio estimation is an easy and accurate measure of normal scaphoid length in situations when the scaphoid is short. It is helpful for the estimation of the size of the bone graft that need for reconstruction of the scaphoid.

Primary medial femoral condyle vascularized bone graft for scaphoid nonunions with carpal collapse and proximal pole avascular necrosis

This study aimed to determine the outcome of free vascularized medial femoral condyle bone grafts in the primary treatment of scaphoid nonunions with scaphoid foreshortening or carpal collapse and intraoperatively documented avascular necrosis. Thirty-two patients (28 male, four female) met the inclusion criteria. Median time from injury to surgery was 70 weeks. Thirty of 32 patients healed at a median of 12 weeks. There was significant improvement from preoperative to postoperative lateral intrascaphoid angle, scapholunate angle, and radiolunate angle. Two scaphoids failed to unite; one patient underwent scaphoidectomy and four-corner fusion 15 months postoperatively after suffering a subsequent injury. Another patient underwent 1,2-intercompartmental supraretinacular artery-based vascularized bone grafting at 4 months postoperatively and then scaphoid excision with four-corner fusion 4 years later. The free vascularized medial femoral condyle bone graft restores scaphoid vascularity and architecture while promoting union in a subset of scaphoid nonunions that has historically been a clinical challenge. Level of evidence: IV.

Treatment for proximal pole scaphoid nonunion with capsular-based vascularized distal radius graft

PURPOSE

We retrospectively reviewed the results of 89 patients with proximal pole scaphoid nonunion, 58 with avascular necrosis, treated with a capsular-based vascularized distal radius graft.

METHODS

Seventy-one male and eighteen female patients with symptomatic nonunion at the proximal pole of the scaphoid were included in this study. No patient had a humpback deformity. In all patients, the vascularized bone graft was harvested from the dorsum of the distal radius and was attached to a capsular flap of the dorsal wrist capsule. After fixation of the scaphoid with a small cannulated screw, the graft was inserted press-fit into the scaphoid trough in the nonunion site. Supplementary fixation of the graft with a microsuture anchor into the scaphoid was used in 66 patients.

RESULTS

At a mean time of 12.3 weeks (range 6-24) after surgery, solid union was achieved in 76 of 89 patients (49 of 58 with avascular necrosis). Eleven patients had persistent nonunion and two fibrous union as determined by CT scan. Sixty-six of the patients with solid bone union were completely pain free, and ten complained of slight pain with strenuous activities. No donor site morbidity was observed.

CONCLUSIONS

The capsular-based vascularized bone graft from the distal radius is a reliable alternative technique for scaphoid nonunions. It is a simple and expedient harvesting technique without the need for a microsurgical anastomoses. The supplemental fixation with a microsuture anchor eliminates the risk of graft displacement.

MDCT arthrography assessment of scaphoid nonunion advanced collapse: distribution of cartilage damage and relationship with scaphoid nonunion features

OBJECTIVES

Our primary aim was to evaluate the distribution and severity of cartilage damage in a sample of patients with scaphoid nonunion advanced collapse (SNAC), assessed on MDCT arthrography, with regard to two well-known SNAC staging systems. Secondarily, we wanted to see if the degree of cartilage damage varied with the location of the nonunion.

METHODS

We retrospectively included 35 patients with a history of SNAC who had undergone MDCT arthrography. The location of the fracture was defined as the proximal, middle, or distal third of the scaphoid. Cartilage damage was assessed in 14 distinct regions of the wrist using a modified Whole-Organ Magnetic Resonance Imaging Score (WORMS) system. Staging of SNAC for each patient was based on the distribution of cartilage damage seen on MDCT arthrography. The one-way ANOVA test was used to evaluate whether global cartilage damage scores differed between patients with proximal vs middle and distal nonunion.

RESULTS

The radial styloid-scaphoid (85.7%), the scaphoid-trapezium-trapezoid (60%), the scapho-capitate (57.1%), and the proximal radio-scaphoid joints (42.9%) were most commonly affected by degenerative cartilage damage. A substantial number of patients could not be classified according to the two SNAC staging systems. Patients with proximal nonunion exhibited a higher mean score of global cartilage damage than patients with middle or distal nonunion: 14.3 ± 9.5 (95% CI 9.8, 18.7) vs 8.6 ± 6.9 (95% CI 4.7, 12.4); p < 0.0001.

CONCLUSION

The distribution of cartilage damage does not always follow the pattern of progressive osteoarthritis widely described in SNAC. Proximal scaphoid nonunion is related to greater severity of global cartilage damage.

Success of scaphoid nonunion surgery is independent of proximal pole vascularity

We followed 35 consecutive patients with scaphoid nonunions in a prospective longitudinal registry. All nonunions were treated with curettage, non-vascularized autogenous grafting and headless screw fixation. Preoperative magnetic resonance imaging, intraoperative bleeding points and histopathological analysis of cancellous bone in the proximal pole were recorded as measures of viability. Healing was categorized as ≥50% bony bridging on computed tomographic images in the plane of the scaphoid. Nine of 23 proximal poles demonstrated ischaemia on magnetic resonance imaging but none were interpreted as infarcted. Twenty-eight of 33 were found to have impaired vascularity as assessed by intraoperative bleeding. Fourteen of 32 demonstrated ≥50% trabecular necrosis and four of 33 demonstrated ≥50% tissue necrosis on histopathological analysis. Thirty of 33 demonstrated focal or robust remodelling activity. Despite pathological evidence of impaired vascularity in over half of the patients, 33 of the 35 scaphoids had healed by 12 weeks. We conclude that proximal pole infarction is decidedly rare and that vascularized bone grafting is seldom required.

LEVEL OF EVIDENCE

IV.

Treatment of the scaphoid humpback deformity - is correction of the dorsal intercalated segment instability deformity critical?

Treatment of scaphoid fractures has been focused mainly on achieving union, with less attention to restoring normal scaphoid shape and orientation. Malalignment of one carpal bone will disrupt the kinetics of the entire wrist. The dorsal intercalated segment instability deformity associated with scaphoid waist nonunion is a nondissociative form of carpal instability. It has to be reduced in the treatment of scaphoid waist nonunions to avoid kinetic problems that will lead to arthritic changes. Computerized tomography scanning has become indispensable to visualize the humpback deformity clearly. Different techniques may be used to restore the normal anatomy of scaphoid, from non-vascularized graft to arthroscopic bone grafting, and also the option of vascularized bone grafting.

Clinical outcome after alternative treatment of scaphoid fractures and nonunions

PURPOSE

Achieving stable fixation of scaphoid fractures and nonunions continues to be a challenge. Compression screw fixation has been the current standard surgical procedure. However, in some cases, bone healing cannot be achieved and requires further revision. Recent series reintroduced volar plating as valid option for stable fixation. The aim of the study was to review clinical outcome of alternative scaphoid treatment.

METHODS

From 2011 to 2014, nine patients with scaphoid fracture were treated by Headless Compression Screw (HCS) and seven patients with scaphoid nonunion by HCS or volar mini condylar plate with bone graft. The average age was 34.4 years and the average time to follow-up was 19.3 months. From 1996 to 1998, 38 patients with scaphoid nonunion were treated using compression screw (S-group) or volar mini condylar plate (P-group) with bone graft. The average age was 39.6 years and the average time to follow-up was 26.2 months.

RESULTS

The union rate was 100%. For scaphoid fractures, the mean Modified Mayo Wrist Score (MMWS) was 94.1 and the DASH score 7.4. From 2011 to 2014, the MMWS was 87.9 and the DASH score 7 in scaphoid nonunions. In the period between 1996 and 1998, the MMWS was 67.2 in the P-group and 58.6 in the S-group, and the DASH score 16.8 and 28.2.

CONCLUSIONS

Our study demonstrated that appropriate application of the HCS was able to produce very satisfactory results in scaphoid fractures and nonunions. In our opinion, however, the method of scaphoid plate osteosynthesis can achieve a higher degree of stability, particularly rotational stability, in case of multifragmentary avascular scaphoid nonunions.

Ilizarov fixation for the treatment of scaphoid nonunion: a novel approach

OBJECTIVES

To evaluate the safety and efficacy of the Ilizarov fine-wire compression/distraction technique in the treatment of scaphoid nonunion (SNU), without the use of bone graft.

DESIGN

This is a prospective study of 20 consecutive patients in one center.

PATIENTS AND METHODS

This study included 20 patients (19 males) with a mean SNU duration of 14.5 months. Four patients had proximal pole, 15 had waist, and 1 had a distal SNU. Patients with carpal instability, humpback deformities, carpal collapse, avascular necrosis, and marked degenerative change were excluded. Following frame application, the treatment comprises three stages: The frame is distracted by 1 mm per day until the radiographs show a 2-3 mm opening at the SNU site (mean 10 days); the SNU site is compressed for 5 days, at a rate of 1 mm per day, with the wrist in 15 degrees of flexion and 15 degrees of radial deviation; the wrist is then immobilized in the Ilizarov fixator for 8 weeks.

RESULTS

Radiographic (radiography and CT scan) and clinical bony union was achieved in all 20 patients after a mean of 90.3 days (70-130 days). All patients returned to their pre-injury occupations. Thirteen patients had excellent results, four good, and three fair, according to the Mayo wrist score.

CONCLUSIONS

In these selected patients, this technique safely achieved bony union without the need to open the SNU site and without the requirement of bone graft.