Checkrein deformity: a case report of two patients with hallux deformity and pain following mandibular reconstruction in oral cancer treatment

Management of Checkrein Deformity

Checkrein deformity is characterized by the dynamic status of the hallux, in which flexion deformity is aggravated by ankle dorsiflexion and relieved by ankle plantarflexion. In most cases, a checkrein deformity occurs secondary to trauma or following surgery. It has been suggested that the flexor hallucis longus tendon tethers or entraps scar tissue or fracture sites. Improvement with conservative treatment is difficult once the deformity has already become entrenched, and surgical management is usually required in severe cases. Various surgical options are available for the correction of checkrein deformities. It includes a simple release of adhesion at the fracture site; lengthening of the flexor hallucis longus by Z-plasty at the fracture site combined with the release of adhesion; lengthening of the flexor hallucis longus by Z-plasty at the midfoot, retromalleolar, or tarsal tunnel area; and flexor hallucis longus tenotomy with interphalangeal arthrodesis for recurrent cases. This review aimed to summarize the overall etiology, relevant anatomy, diagnosis, and treatment of checkrein deformities described in the literature.

Application of ultrasound in preoperative localization diagnosis of checkrein deformity: A retrospective case series

BACKGROUND

Checkrein deformity, is a rare claw toe dynamic deformity of the hallux or great toe. This study investigated the use of diagnostic ultrasound in positioning the accurate injury location causing checkrein deformity and its clinical significance for etiological diagnosis and selection of surgical methods.

METHODS

This retrospective study included patients with confirmed checkrein deformities (according to typical symptoms) at the Department of Traumatic Orthopedics of Tianjin Hospital (Tianjin, China) from March 2017 to July 2021.

RESULTS

A total of 11 patients (8 males and 3 females) with a mean age of 36.7 ± 16.8 (range 19-61) were included in this study. The injuries included six cases of tibia and fibula fracture, one case of single tibia fracture, and one case of single fibula fracture. Four patients were treated with steel plate internal fixation, three patients with intramedullary nailing, and one patient with external fixation. Three patients reported no history of any high-energy trauma or surgery. The ultrasound results showed that seven patients suffered from flexor hallucis longus (FHL) lesions, two patients suffered from flexor digitorum longus (FDL) lesions, and two patients suffered from FHL and FDL lesions. The patients underwent different surgeries tailored to their specific lesions. Toe flexion deformity was completely corrected after operation in all patients. The function of the toes was recovered to varying extent.

CONCLUSION

The results of this study demonstrates that the checkrein deformities can be confirmed by ultrasound. It could be used to determine the adhesions before the operation, acting as guidance while establishing the surgical planning.

Retro-Malleolar Z-Plasty of Flexor Hallucis Longus Tendon in Post-Traumatic Checkrein Deformity: A Case Series and Literature Review

Checkrein deformity (CD) is a dynamic deformity of the hallux characterized by flexion contracture of the interphalangeal (IF) joint and extension contracture of the metatarsophalangeal (MTP) joint, worsened by ankle dorsiflexion. It is due to post-traumatic or ischemic retraction of the long hallux flexor tendon (FHL) following soft tissue trauma, leg fractures, ankle fractures and, more rarely, calcaneal or talar fractures. Diagnosis is essentially clinical, associated with imaging, to rule out unrecognized causes and evaluate fracture healing process. Few cases are reported in literature without univocal treatment. Background and Objectives: To analyze clinical and functional outcomes in patients with CD treated with release and retro-malleolar Z-plasty lengthening of FHL tendon. Materials and Methods: Patients diagnosed with CD treated with retro-malleolar (at tarsal tunnel) Z-plasty lengthening of the FHL tendon between January 2016 and August 2020 were included. Clinical and functional outcomes were collected on admission and post-surgery and analysed retrospectively. Patients with a minimum follow-up of 18 months were included. Results: A total of 14 patients, with mean age of 37.4 years old, with CD diagnosis were included in the study. All patients were suffering from post-traumatic CD and the mean time from trauma to onset of deformity was of 7 months (range 1−12). At a mean follow-up of 31.8 months (range 18−48) we found a significant improvement (p < 0.05) in terms of pain relief (VAS), function (AOFAS score) and ROM of the IP and MTP hallux joints. No recurrence, loss of strength, nerve injury or tarsal tunnel syndrome were observed. No patient required revision surgery. Conclusions: In this case series the retro-malleolar FHL tendon Z-plasty proved to be a suitable option for CD correction, allowing a good clinical and functional recovery.