Micro Screw Fixation for Small Proximal Pole Scaphoid Fractures with Distal Radius Bone Graft

High Rate of Union of Scaphoid Pseudoarthrosis Treated With Arthroscopic Olecranon Bone Graft Using Antegrade Percutaneous Headless Compression Screw

PURPOSE

To assess the healing rate of scaphoid pseudoarthrosis treated with wrist arthroscopy, olecranon bone graft, and anterograde screw fixation, as well as evaluate complications and clinical and radiologic outcomes.

METHODS

All patients with scaphoid nonunion were selected between January 2017 and December 2022. Inclusion criteria were patients between 18 and 60 years of age, a diagnosis of scaphoid pseudoarthrosis, complete clinical patient-reported outcomes, radiographic measurements, and at least a 1-year follow-up. Scaphoid pseudoarthrosis was treated arthroscopically with olecranon bone graft and anterograde screw fixation. Clinical assessment was performed through visual analog scale (VAS) for pain, QuickDASH (Disabilities of the Arm, Shoulder, and Hand) questionnaire, wrist range of motion using a standard goniometer, and grip strength in kilograms with a Jamar hydraulic hand dynamometer. Clinical relevance was measured with the minimal clinically important difference (MCID) for VAS and QuickDASH. Scapholunate angle was measured. Union was assessed on a computed tomography scan.

RESULTS

Seventeen patients were included with a mean follow-up of 17.2 months. The mean age was 30.1 years, and the average time from injury to arthroscopic surgery was 11.1 months. At latest follow-up, there was an improvement in VAS pain score and QuickDASH score. Range of motion and grip strength increased at last follow-up. MCID threshold for the VAS and QuickDASH score was reached by 100% and 94.1%, respectively. Union was achieved in 16 patients (94.1%) after a median of 16 weeks (interquartile range, 16-20).

CONCLUSIONS

Arthroscopic treatment of scaphoid pseudoarthrosis with olecranon bone graft and antegrade percutaneous headless compression screw allows a high grade of union and improves pain and function at short-term follow-up.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

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

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

Headless screw fixation through the dorsal rough surface for proximal-pole scaphoid-nonunion: a report of 15 patients

Clinical outcomes of the dorsal-retrograde headless screw-fixation technique in 15 patients with proximal scaphoid nonunion are presented. In this technique, screws are inserted from the dorsal rough surface of the scaphoid, located between the dorsal ridge and scaphoid-trapezium-trapezoid joint. Fifteen patients underwent osteosynthesis with this technique with iliac bone graft. Seven patients required primary surgery, and eight patients with a history of failed operation required revision surgery. Among 15 patients, 13 achieved union and two with persistent nonunion were asymptomatic with average follow-up of 24 months (range 14-57). Mean time to union was 20 weeks (range 12-40). Our experience with the dorsal-retrograde headless screw fixation technique has shown encouraging results for the treatment of proximal-scaphoid nonunion, especially in revision surgery wherein secure fixation of the small proximal fragments can be difficult using conventional anterograde techniques.Level of evidence: IV.

Acute scaphoid fractures: guidelines for diagnosis and treatment

In cases of suspected scaphoid fracture where the initial radiographs are negative, a supplementary MRI, or alternatively CT, should be carried out within three to five days.

Fracture classification, assessment of dislocation as well as evaluation of fracture healing is best done on CT with reconstructions in the coronal and sagittal planes, following the longitudinal axis of the scaphoid.

After adequate conservative management, union is achieved at six weeks for approximately 90% of non-displaced or minimally displaced (≤ 0.5 mm) scaphoid waist fractures.

Scaphoid waist fractures with moderate displacement (0.5–1.5 mm) can be treated conservatively, but require prolonged cast immobilization for approximately eight to ten weeks.

Internal fixation is recommended for all scaphoid waist fractures with dislocation ≥ 1.5 mm.

Distal scaphoid fractures can be treated conservatively. The majority heal uneventfully after four to six weeks of immobilization, depending on fracture type.

In general, proximal scaphoid fractures should be treated with internal fixation.

Cite this article: EFORT Open Rev 2020;5:96-103. DOI: 10.1302/2058-5241.5.190025

[Advances in diagnosis and treatment of acute scaphoid fractures]

OBJECTIVE

To review the advances in diagnosis and treatment of acute scaphoid fractures.

METHODS

The characteristic, classification, diagnosis, and treatment of acute scaphoid fractures were reviewed and summarized.

RESULTS

As one of the common fracture in hand, scaphoid fractures are generally classified as either undisplaced and stable or displaced and unstable. CT and MRI has best diagnostic specificity and sensitivity respectively. Most undisplaced and stable fractures can be treated successfully by plaster immobilization, whereas the displaced and unstable fractures have great prognosis after open reduction and internal fixation.

CONCLUSION

Acute scaphoid fractures should be diagnosed and treated at an early stage, and choose the appropriate treatment according to the location and stability of the fracture.