[Mallet-thumb--presentation and discussion of 3 cases of a rare lesion]

Surgical treatment of the bony mallet thumb: a case series and literature review

INTRODUCTION

The aim of this study was to provide a more precise statement on the outcome after surgical treatment of a bony mallet thumb and possibly give a treatment recommendation regarding the surgical fixation method.

PATIENTS AND METHODS

All patients (n = 16) who underwent a surgical treatment for an acute bony mallet thumb fracture between January 2006 and July 2019 were enrolled. The surgical method, complications, the range of motion, tip pinch, lateral key pinch, overall grip strength, visual analog score, Disability of the Arm, Shoulder and Hand Score, Mayo Wrist Score, Patient-Rated Wrist Evaluation Score, Buck-Gramcko Score and radiologic parameters were evaluated. Further, a comprehensive literature search on PubMed was conducted covering a period from 1956 to 2021 to include all possible matching articles on the treatment of the bony mallet thumb (n = 21 articles).

RESULTS

Surgical treatment was very inhomogenous including indirect and direct K-wire fixation, screw fixation, plate fixation and anchor fixation methods. The IP joint range of motion and thumb strength ranged from 66 to 94% in comparison to the contralateral side. An open reduction led to worse functional scores compared to a closed reduction. Treatment methods in the literature were also very inhomogenous with a very low patient count, often even pooling data of bony mallet thumb fractures with bony mallet finger fractures. The risk for infection was higher in K-wire fixation methods than in open reduction and internal fixation methods.

CONCLUSION

The evidence for the best treatment of a bony mallet thumb fracture is low. On one hand the functional outcome can be inferior using an open reduction approach, but on the other hand, K-wire fixation methods with a closed reduction approach showed a higher risk for infection. Future multi-center research must be conducted to find the best treatment procedure for the best outcome of the patient.

Closed mallet thumb injury: Our experience of 10 patients treated with surgery and a systematic review

OBJECTIVE

This retrospective study reports 10 patients with closed mallet thumb injury treated with surgery and compares the clinical outcomes achieved with those of previously described patients who were treated with either conservative therapy or surgery.

METHODS

We report the outcomes of a series of 10 patients who received surgical treatment at our institutions. Due to the rarity of closed mallet thumb, a systematic review was conducted, and the results of a literature search were compared with our case series to strengthen our conclusions. The previously described patients were categorized into two groups: the surgically treated group (16 patients) and the conservatively treated group (10 patients). The following patient and injury characteristics were documented: age, gender, injured side, time from injury to treatment, mechanism of injury, extension lag at first visit, postoperative range of motion (ROM) of the interphalangeal joint, immobilization period, and follow-up period.

RESULTS

Statistical analyses showed no significant differences in the clinical results, except for shorter immobilization periods between our series and the previously described patients involving conservative treatment (4.9 ± 0.9 vs. 9.5 ± 2.3 weeks, respectively; P = 0.0053).

CONCLUSIONS

This study suggests that surgery may result in more rapid recovery.

Bony mallet thumb

Unlike mallet finger, mallet thumb is rare. We treated a case of mallet thumb with avulsion fracture using extension block Kirchner wire technique, and achieved excellent results.

Closed mallet thumb injury: a review of the literature and case study of the use of magnetic resonance imaging in deciding treatment

SUMMARY

At present, the literature dedicated to closed mallet thumb injury offers conflicting evidence between conservative and operative approaches. Although conservative treatment is often successful, retraction of the extensor pollicis tendon may lead to improper reattachment and continued deformity. This discussion and case report serve to highlight the use of magnetic resonance imaging as an adjunct in selecting the proper treatment strategy for this injury at initial presentation.