A retrospective study of closed extension block pinning for mallet fractures: Analysis of predictors of postoperative range of motion

Retrospective study of Ishiguro's technique for mallet bone finger in children: long-term follow-up and analysis of predictors in outcomes

PURPOSE

There is no consensus on the optimal treatment of bony mallet finger in the paediatric population due to a lack of studies in children. The Ishiguro technique is simple and less invasive, and treatment with K-wire fixation seems to provide better results for extension lag in bony mallet finger according to the literature. A retrospective cross-sectional study with long-term follow-up was performed to evaluate the functional and clinical outcomes of this method in children. Preoperative and intraoperative predictors of outcome were investigated.

METHODS

From June to December 2022, we evaluated 95 children who underwent extension K-wire block from 2002 to 2012. Eighty-four children were included (mean age 14.8 ± 1.68 years) for a mean long-term follow-up of 11.6 ± 2.3 (8-16) years. Clinical and radiographic features were assessed. Pain and functional outcomes were assessed using Crawford criteria, range of motion (ROM) at the distal interphalangeal joint (DIPJ), loss of extension, and VAS scale. Univariate and multivariate regressions were used to assess which variables might predict the worst outcomes at long-term follow-up.

RESULTS

Bone union and pain relief were always achieved. There were no complaints of potential growth impairment or nail deformity. 82.1% of patients showed excellent and good results. Fifteen patients had fair results.

CONCLUSIONS

Although there are currently no significant differences between surgery and orthosis in adults, the Ishiguro technique is more effective in children when it comes to outcomes in the treatment of mallet fingers. A high percentage of excellent and good results were achieved, and no epiphyseal damage or nail deformity was reported. A strong and significant correlation was found between the worst outcomes and either delayed treatment time or excessive flexion angle.

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 interfragmentary pinning versus the extension block technique for acute Doyle type 4c mallet finger

The aim of this study was to compare the closed reduction interfragmentary pinning method (IPM) with the extension block technique (EBT) for bony mallet finger. Patients who underwent mallet finger operations were screened retrospectively for the following inclusion criteria: Doyle type 4c, age between 18 and 75 years, less than 4 weeks to surgery, and more than 1 year of follow-up time. Group I underwent a closed reduction IPM, and group II underwent the EBT. Lateral radiographs taken during the preoperative and final examination were used to evaluate the size and amount of displacement from the distal interphalangeal (DIP) joint and the dorsal fragment as well as the articular surface. Operation times were compiled from patient records. During the final examination, pain and DIP joint range of motion (ROM) were assessed and complications were recorded. The Crawford criteria were used for functional results. Fifteen patients in group I (8 men, 7 women) and 17 patients in group II (10 men, 7 women) were evaluated. Age, gender, time to surgery and follow-up time showed no statistically significant differences between the two groups. The differences in fragment size, preoperative and postoperative joint displacement, amount of dorsal displacement and DIP joint ROM were not statistically significant between the two groups. However, the operation time was significantly shorter time in group I than in group II (p=0.000). The average time to fracture union was significantly longer in group I (7.3 weeks) than in group II (6 weeks) (p=0.013). The EBT has faster time to union and is a safer method with lesser risk of arthritis and fragmentation. The IPM can be an alternative with shorter operation time, less pin bed infection and nail bed damage, especially in Doyle type 4c cases with large fragments.