A systematic review of the non-operative treatment of nightstick fractures of the ulna

Risk Factors for Failure of Nonsurgical Management of Ulnar Shaft Fractures

PURPOSE

Isolated ulnar shaft fractures are frequently managed nonsurgically. However, rates of nonsurgical treatment failure remain substantial, and risk factors for the failure of nonsurgical management are not well described. This study investigated radiographic and patient-specific risk factors for the failure of nonsurgical management of isolated ulnar shaft fractures.

METHODS

A retrospective review of patients with ulnar shaft fractures initially treated nonsurgically was performed at two tertiary referral centers over a 19-year period from 2001 to 2020. Patient- and injury-related variables, surgical interventions, and plain radiographic measurements were recorded. The outcome of interest was failure of nonsurgical management, defined as failure to achieve fracture union nonsurgically within 3 months of injury.

RESULTS

One hundred fifty four patients initially treated nonsurgically for isolated ulnar shaft fractures were included. Twenty six patients (17%) experienced failure of nonsurgical management; these included five nonunions, 16 delayed unions, and 10 conversions to surgical management. Patients who experienced failure of nonsurgical management had a higher prevalence of diabetes mellitus, a higher employment rate, and fractures with higher initial median posteroanterior and lateral translations, fracture gap, and angulation; 83% of the patients with an initial fracture gap of ≥4 mm and 41% of the patients with an initial fracture angulation of >10° failed nonsurgical management.

CONCLUSIONS

Although most ulnar shaft fractures heal successfully with nonsurgical management, a substantial percentage of these fractures do not. Patients who are currently working, have diabetes mellitus, or have fractures with an initial fracture gap of ≥4 mm or an initial fracture angulation of > 10° may be more likely to fail nonsurgical treatment, although additional studies with larger sample sizes are needed to confirm these associations.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

The Radiographic Union Score for ulnar fractures (RUSU) predicts ulnar shaft nonunion

AIMS

To develop a reliable and effective radiological score to assess the healing of isolated ulnar shaft fractures (IUSF), the Radiographic Union Score for Ulna fractures (RUSU).

METHODS

Initially, 20 patients with radiographs six weeks following a non-operatively managed ulnar shaft fracture were selected and scored by three blinded observers. After intraclass correlation (ICC) analysis, a second group of 54 patients with radiographs six weeks after injury (18 who developed a nonunion and 36 who united) were scored by the same observers.

RESULTS

In the initial study, interobserver and intraobserver ICC were 0.89 and 0.93, respectively. In the validation study, the interobserver ICC was 0.85. The median score for patients who united was significantly higher than those who developed a nonunion (11 vs. 7, p < 0.001). A ROC curve demonstrated that a RUSU ≤ 8 had a sensitivity of 88.9% and specificity of 86.1% in identifying patients at risk of nonunion. Patients with a RUSU ≤ 8 (n = 21) were more likely to develop a nonunion (n = 16/21) than those with a RUSU ≥ 9 (n = 2/33; OR 49.6, 95% CI 8.6-284.7). Based on a PPV of 76%, if all patients with a RUSU ≤ 8 underwent fixation at 6 weeks, the number of procedures needed to avoid one nonunion would be 1.3.

CONCLUSION

The RUSU shows good interobserver and intraobserver reliability and is effective in identifying patients at risk of nonunion six weeks after fracture. This tool requires external validation but may enhance the management of patients with isolated ulnar shaft fractures.

Management of Isolated Ulnar Shaft Fractures

» Most isolated ulnar shaft fractures are stable and heal without complication regardless of treatment protocol.» Casting above the elbow may create unwanted stiffness without enhancing union rates.» Defining unstable fractures and determining which injuries would benefit from operative management remain a challenge.» Recent development of intramedullary devices has shown promise in preliminary studies, but more vigorous investigation is needed to determine their role.

A comparative study of fixation methods in adults with two-thirds distal isolated ulnar shaft fractures with a minimum of 2 year follow-up

BACKGROUND

Adult isolated ulnar shaft fractures (IUSF) are rare. There remains a need to establish the best methods to manage these fractures. The aim of this study was to compare two forms of treatment for IUSF: intramedullary stabilization by k-wire (IMF) versus Open Reduction Internal Fixation by plating (ORIF), in order to identify differences in clinical (1) and radiological outcomes (2), as well as comparative costs (3).

HYPOTHESIS

The hypothesis of this study was assessing whether intramedullary stabilization was as feasible as plating in the treatment of isolated ulnar shaft fractures in clinical practice.

PATIENTS AND METHODS

A retrospective analysis was undertaken on patients diagnosed IUSF between January 2015 and March 2017 with a minimum of 2 years follow-up. They were treated with IMF (group 1) or ORIF (group 2). Demographic information, clinical outcomes and complications were collected. Cost, including implant cost, operative time, sterilization and inpatient stay were compared. Radiographs were reviewed to evaluate axial angulation, shortening, displacement and residual deformity.

RESULTS

54 patients with a mean age of 41.2 years were treated by IMF (27/54) and ORIF (27/54). The mechanism of injury included high-energy (55%) and low-energy falls (45%). AO/OTA 2018 fracture classification was simple (39/54), wedge (14/54) and complex (1/54). The locations were 37/54 (70%) distal third and 17/54 (30%) mid-shaft fractures. There was no significant difference pre and post-operatively between the 2 groups regarding radiologic criteria. 3 cases of non-union, 4 delay-union and 1 regional complex syndrome occurred in group 2. No complication was reported in group 1. The function determined by range of motion (ROM) at wrist and elbow was excellent in 72% (group 1) and 80% (group2), 18% satisfactory in group 1 and 20% in group 2. There was no difference for QuickDASH and pain. Implant removal was necessary in 70% of patients without sequelae in nailing, 11% after plating. Average operation time was 29 ± 5 min for ORIF and 18 ± 6 min for IMF. Total estimated cost per patient was 3678.4€ for IMF and 7051.9€ for ORIF.

CONCLUSIONS

Compared with ORIF, IMF significantly reduced the operation time and cost with lower complications.

TYPE OF STUDY

Retrospective study.

TYPE OF PROOF

Level 4.

The Emergent Evaluation and Treatment of Elbow and Forearm Injuries

This article provides an updated review of the emergent evalution and treatment of elbow and forearm injuries in the emergency department. Clinically necessary imaging is discussed. Common and uncommon injuries of the elbow and forearm are reviewed with an emphasis on early recognition, efficient management, and avoidance of complications. The astute emergency physician will rely on a focused history and precise examination, applied anatomic knowledge, and strong radiographic interpretative skills to avoid missed injuries and complications.

Nightstick Fractures, Outcomes of Operative and Non-Operative Treatment

Introduction: A nightstick fracture is an isolated fracture of the ulnar shaft. Although operative and non-operative treatments have been commonly decided by the degree of displacement of the fracture, still there is a controversy specially in those moderately displaced. Herein we report our experience with nightstick fractures. Objective: To evaluate operative and non-operative treatment of nightstick fracture. Materials and methods: We retrospectively reviewed the clinical notes, physiotherapy letters and radiographs of 52 patients with isolated ulnar shaft fractures. Outcome Measurements included radiographic healing, post-operative range of motion and complications. Results: The study included 13 females and 39 males, with a mean age of 26 years [range, 18–93 years]. The mean Follow-up period was 32 months ranged from 12 to 54 months. Ten patients were treated non-operatively; forty-two patients had open reduction and internal fixation including six open fractures. The average wait for surgery was 2.5 days. Mobilisation was commenced immediately after the surgeries non-load bearing. 40 patients had no complications post-operatively with good outcome and average of four visits follow-up. In the non-operative group, five out ten failed and had a mean follow-up of nine visits. Conclusion: Satisfactory outcome is to be expected with open reduction and internal fixation. Fractures with less than 50% displacement should be treated on individual bases, considering; age, pre-morbid functional status, co-morbidities, compliance and associated injuries.

Impact of Distal Ulnar Fracture Malunion on Distal Radioulnar Joint Instability: A Biomechanical Study of the Distal Interosseous Membrane Using a Cadaver Model

PURPOSE

Certain distal ulna fractures may contribute to distal radioulnar joint (DRUJ) instability. We hypothesized that residual distal ulna translation could affect DRUJ stability by slackening the distal interosseous membrane (DIOM). We aimed to test this hypothesis in a cadaver model.

METHODS

We created an ulnar translated distal ulna fracture model in 6 cadavers. Dorsal and palmar displacements of the ulna relative to the radius were measured and DRUJ instability was staged under the following conditions: (1) 0-, 2-, and 4-mm ulnar translation of the distal ulna with an intact triangular fibrocartilage complex (TFCC) and DIOM; (2) 0-, 2-, and 4-mm translations with TFCC divided and an intact DIOM; and (3) a 0-mm translation with TFCC and DIOM divided.

RESULTS

With an intact TFCC, dorsal and palmar displacements were not increased with any amount of distal ulna translation. After TFCC division with 0-mm translation, dorsal displacement increased significantly with DRUJ dislocation, whereas palmar displacement increased to a lesser extent with DRUJ subluxation. Palmar displacement gradually increased as the translation increased, and with 4-mm translation the ulnar head displaced to a perched position off the sigmoid notch. With TFCC and DIOM division, displacements increased markedly with DRUJ dislocation both dorsally and palmarly.

CONCLUSIONS

Dorsal dislocation occurred when the TFCC was divided regardless of the amount of distal ulna translation. Palmar subluxation occurred when the TFCC alone was divided. Palmar displacement to a perched position occurred because of slackening of the DIOM as a result of translation of the distal ulna. Bidirectional DRUJ instability with dorsal dislocation and palmar displacement to a perched position occurred when the TFCC was divided and the distal ulna was ulnarly translated.

CLINICAL RELEVANCE

Bidirectional DRUJ instability might occur when distal ulna translation deformity is associated with TFCC injury because the DIOM loses its function as a secondary stabilizer.