Arthroscopic Bone Graft and Internal Fixation of Non-Union of the Proximal Pole of the Scaphoid: Surgical Technique and Outcomes

Arthroscopic bone grafting in scaphoid fracture nonunion: Is it a universal solution?

Since 1997, arthroscopic bone grafting has offered hand surgeons a solution to the riddle of scaphoid fracture nonunion. The intended merit of an arthroscopic approach for scaphoid fracture nonunion management lies in its minimal invasiveness, which preserves the tenuous vascularity of the scaphoid, poses minimal disturbance to carpal ligaments, and allows comprehensive evaluation in diagnostic uncertainty. What does the evidence tell us about its outcomes and limitations compared to open techniques? Level III evidence suggests that arthroscopic bone graft yields similar union rates and potentially earlier time to union compared to open bone graft, at an average union rate of 96 % and union time of 13.5 weeks. It offers a universal solution to scaphoid fracture nonunion, with similar union rate and time achieved regardless of smoking, chronicity, proximal fracture or avascular necrosis. Radiological correction of humpback deformity and dorsal intercalated segment instability (DISI) may be inferior compared to an open technique, but correction to within normal range is still possible. Hence, it's long term clinical implication remains unclear. Perhaps the only true contraindications to arthroscopic bone grafting are proximal pole fragmentation due to unsalvageable necrosis, or advanced scaphoid nonunion advanced collapse (SNAC). While it is easy to get lost in the debate of biology and the necessity of vascularized bone graft, ultimately, fracture healing is multifactorial and surgeons must not neglect the mechanical importance of well placed instrumentation.

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

Purpose

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

Methods

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

Results

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

Conclusions

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

Type of study/level of evidence

Therapeutic IV.

Arthroscopic treatment of scaphoid nonunion, a new algorithm after six years practice

INTRODUCTION

Scaphoid nonunion is still a challenging problem in hand surgery. Till now most of the patients have been treated with open revision, bone grafting and internal stabilization. Arthroscopy plays an increasing role in hand surgery since the last decade. In this retrospective study, we want to present our results and current treatment protocol, adapted after midterm analysis.

MATERIAL AND METHODS

In 2017, arthroscopic treatment of scaphoid nonunion was started at our department. Debridement is done arthroscopically as well as insertion of radius cancellous bone graft. Fixation has been accomplished with K-wires and/or head compression screws percutaneously, by help of fluoroscopy. Till 2020, 24 patients were treated, observing three delayed unions, treated successfully by extra corporal shockwave therapy and modifying the fixation. A subsequent analysis of the results yielded the modification of our fixation methods, and consequently, all patients received shockwave therapy as well.

RESULTS

Comparing the success rate with the 28 operated after 2020, the adaption of our algorithm showed an improvement of the healing rate from 87 to 96%. There we found only one ongoing nonunion in the proximal 1/3. The median time to bony healing was comparable in the two groups, operation time showed no significant difference. After a median follow-up of 30 months, an excellent range of motion could be found, as well as a significant reduction in pain and grip strength matchable with the unaffected hand in all 52 patients. DASH and Mayo Wrist Score showed satisfactory results, and 45 patients came back to their earlier occupation and sports.

CONCLUSION

Arthroscopy has a fix place in the algorithm for scaphoid nonunion in our institution. It is hypothesized that the implementation of an adequate and stable fixation on the section of the nonunion is indispensable. The distal radius is a sufficient donor-site for cancellous bone grafting. Extra corporal shockwave therapy is from now on used routinely in arthroscopic treatment of scaphoid nonunion.

LEVEL OF EVIDENCE

IV.

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

Background

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

Methods

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

Results

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

Conclusion

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION AND FUTURE DIRECTIONS

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

Arthroscopy-assisted Procedures in Hand and Wrist Surgery: An Update. Where Are We So Far?

Wrist and hand arthroscopy, despite being an old tool, has gained popularity and advanced in assisting in the treatment of various injuries and conditions in the region in recent years. Dorsal, volar, ulnar, and radial accessory portals are used to reach all points of the carpal and hand joints. The minimal tissue damage, lesser injury to the capsule and its mechanoreceptors, the assessment of injuries associated with the reason for surgery, and aesthetically more favorable scars have attracted many doctors and their patients. As a result, there has been an increase in publications and diversifications of arthroscopic techniques. The aim of this update article is to present the advances and the evidence available in the literature to assist readers in their decision on which technique to use in the treatment of wrist and hand conditions.

Arthroscopic bone graft and fixation for proximal scaphoid nonunions

AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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