Extension block technique for mallet fractures: a comparison of one and two dorsal pins

Comparison of extension block pinning technique versus pin orthosis-extension block pinning technique for acute mallet fractures: a prospective randomized clinical trial

INTRODUCTION

The extension block pinning technique (EBPT) is a popular surgical treatment for mallet fractures; however, it has several drawbacks. The purpose of this randomized clinical trial was to compare EBPT to the pin orthosis-extension block pinning method (PO-EBPT) in the treatment of mallet fractures involving more than one-third of the joint surface but without primary joint dislocation.

MATERIALS AND METHODS

Sixty-five patients with mallet fractures were randomized into two groups between June 2017 and January 2020: Group I (33 patients) was treated with EBPT and group II (32 patients) was treated with PO-EBPT. Five patients were lost to follow up due to lack of follow-up and death. There were no significant differences in the clinical and demographic characteristics of both groups. Patients were evaluated according to fracture union, extension lag, distal interphalangeal (DIP) joint range of motion, Crawford's criteria, and complication rates. The patients were followed-up post-operatively at 2 weeks, 6 weeks, 3 months, 6 months, 1 year, and annually thereafter.

RESULTS

A total of 60 patients were randomized into two groups: one (30 patients) was treated with EBPT and the second (30 patients) with PO-EBPT. There were no significant differences between the two groups in terms of fracture union and active DIP joint flexion (P = 0.743 and P = 0.059, respectively). The mean extension lag of the DIP joint in the EBPT group was significantly greater than the PO-EBPT group (10° ± 9.47° vs. 4.17° ± 7.2°, P = 0.009). According to the Crawford criteria, the PO-EBPT group showed significantly better outcomes (P = 0.005). The complication rates were similar between groups (P = 0.45).

CONCLUSION

In comparison to the EBPT technique, the group of patients operated with PO-EBPT had superior clinical outcomes and less loss of extension at the DIP joint according to the Crawford's criteria.

Extension Block Pinning versus percutaneous Fragment Reduction with a Towel Clip and extension Block Pinning with direct Pin Fixation for Treatment of Mallet Fracture

PURPOSE

This study compared the clinical and radiographic results between extension block pinning (Group A) and percutaneous reduction of the dorsal fragment with a towel clip followed by extension block pinning with direct pin fixation (Group B) for the treatment of mallet fractures.

PATIENTS AND METHODS

A total of 69 patients (group A = 34 patients, group B = 35 patients) who underwent operative treatment for mallet fractures from June 2008 to November 2017 with ≥ 6 months post-surgical follow-up were analysed retrospectively. The extent of subluxation of the distal interphalangeal joint, articular involvement of fracture fragment, fracture gap, and articular step-off were examined on plain radiographs before and after surgery. The functional outcomes were evaluated with the Crawford rating system.

RESULTS

The postoperative step-offs were 0.16 mm in group A and 0.01 mm in group B. Group B had a significantly better anatomical outcome than group A. Five patients in group A had a loss of reduction. Among them, two had malunion and post-traumatic arthritis. Meanwhile, no patients in group B presented with loss of reduction and nonunion. The mean extension lags were 4.2° in group A and 1.6° in group B. However, functional outcome did not differ between the two groups at the final follow-up.

CONCLUSION

Fracture reduction using a towel clip and extension block pinning with direct pin insertion for mallet fracture facilitated the anatomical reduction of fragments, and allowed for stable fixation of fragments. Compared with extension block pinning technique, this technique has shown better anatomical results and stability, but not better clinical results.

Comparison of single and double dorsal wires in the extension block technique for mallet fractures: Retrospective observational study

Mallet fractures are avulsion fractures of the extensor tendon from the distal phalanx base and often occur due to sudden flexion or axial loading. In this study, we aimed to compare the clinical and radiological results of patients treated with single and double dorsal wires from the dorsal in the extension block method.Patients to whom a single wire from dorsal was applied were assigned to Group 1 (n: 22), and those to whom double wires were applied were assigned to Group 2 (n: 23). Surgical treatment was decided for patients with more than 1/3 of the fracture fragment containing the joint surface and volar subluxation. The range of motion of the distal interphalangeal (DIP) joint was measured with a goniometer. The displacement of the fragment was measured before and after surgery on lateral radiographs. The presence of bridging callus formation on anterior-posterior and lateral radiographs was evaluated for a union.There were 30 male (66.7%) and 15 (33.3%) female patients. The mean age of the patients was 32 years. Radiographic union was obtained in all patients. Pseudoarthrosis was not observed in any patient. The Crawford score was excellent in 13 (28.9%) cases, the score was good in 18 (40%) cases, the scores were moderate in 13 (28.9%) cases, and the score was poor in 1 case (2.2%). There were no complications in 35 (77.8%) cases, dorsal bump complications occurred in 9 cases (20%), and osteoarthritis and dorsal bump complications occurred in 1 (2.2%) case. We did not observe nail deformity, skin necrosis, infection, or fingertip sensitivity. We found similar functional and clinical results between the groups.We recommend using single dorsal wire, as using double dorsal wires requires extra operation time, effort, and fluoroscopy.

Delayed Extension Block Pinning in 27 Patients With Mallet Fracture

Background: Untreated bony mallet fingers can cause an array of problems; therefore, adequate treatment is essential. The primary aim of this study was to determine the patient-reported functional outcome of delayed surgical intervention of bony mallet fingers. The secondary aim was to determine the complication rate of delayed surgical intervention. Methods: In this single-center retrospective cohort study, all consecutive patients treated between 2010 and 2016 at our level 2 regional teaching hospital were included. Inclusion criterion was a bony mallet finger injury (excluding the thumb), presenting >21 days after injury, treated with extension block pinning. Indications for surgery were >2 mm fragment displacement or volar subluxation of the distal interphalangeal joint. Six to 82 months postoperatively, patients completed the Patient-Rated Wrist and Hand Evaluation (PRWHE) by phone. Complications were extracted by chart review. Results: Twenty-seven patients were included, and all completed the PRWHE. Median time to surgery was 35 days (interquartile range [IQR] = 29-42; range = 22-61). Reasons for delay in surgical treatment were patient/physician delay in 24 cases and failed conservative treatment in 3 cases. The median PRWHE score was 0 (IQR = 0-5; range = 0-22.5). After retrospective assessment of the outpatient charts, no early symptoms of malunion or nonunion were found. One patient had a loss of Kirschner-wire fixation, which was corrected. Three patients had an infection that required antibiotic treatment. Conclusions: Delayed surgical management of bony mallet fingers demonstrated adequate functional outcome with minimal complications when compared with prior literature.

The Outcomes of Extension Block Pinning and Nonsurgical Management for Mallet Fracture

PURPOSE

We aimed to compare the clinical and radiographic results of patients with a mallet fracture involving more than one-third of the articular surface, but without a high degree of distal interphalangeal (DIP) joint subluxation, treated with extension block pinning or nonsurgical management.

METHODS

Forty-nine patients with a mallet fracture involving more than one-third of the articular surface were reviewed. Twenty-six cases were treated using extension block pinning (surgery group) and 23 were treated nonsurgically (nonsurgical group). At the final follow-up, extension lag and flexion of the DIP joint of the affected digit were measured. Distal interphalangeal joint pain was rated using a visual analog scale and the overall clinical outcomes were graded using Crawford's criteria. Complications, including nail deformity and dorsal prominence, were also assessed. The rate of DIP joint subluxation and fracture fragment size were radiographically evaluated.

RESULTS

Mean extension lag and flexion of the DIP joint and mean visual analog pain scores were not significantly different in the 2 groups. Outcomes, as assessed using Crawford's criteria, were excellent in 5, good in 12, fair in 6, and poor in 3 in the surgery group, and excellent in 2, good in 11, fair in 8, and poor in 2 in the nonsurgical group. Moreover, the frequency of nail deformity or dorsal prominence was similar in the 2 groups. The rate of DIP subluxation and mean fracture fragment size were similar between the 2 groups. All the fractures had united by 3 months after injury in both groups.

CONCLUSIONS

The clinical outcomes do not significantly differ between extension block pinning and nonsurgical management for mallet fractures involving more than one-third of the articular surface, but without high degree subluxation of the DIP joint.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.