Comprehensive classification and its value of capitellar cartilage injury concomitant with radial head fracture.

Background: There are defects in the existing classification of capitellar cartilage injury (CCI) concomitant with radial head fracture (RHF). This study aimed to introduce a comprehensive classification of CCI and to analyze its surgical guidance value.

Methods: According to the affected site and severity, CCI was classified into four types: Type I - partial-thickness loss of articular cartilage, Type II - full-thickness loss of articular cartilage, Type III - full-thickness loss of articular cartilage with subchondral bone loss, Type IV - full-thickness loss of articular cartilage with thin cortex loss on the border of the capitellum; Different types suggest different surgical methods. Between January 2017 and January 2023, this comprehensive CCI classification was applied in 31 operated patients with CCI concomitant with RHF. The ranges of motion (ROM), Mayo Elbow Performance Index (MEPI) score, Hospital for Special Surgery (HSS) score and visual analog scale (VAS) for pain, were used to evaluate the functional recovery of the affected limb.

Results: Mason Type I-IV RHF accounted for 6.45%, 38.71%, 48.39%, and 6.45%, respectively. Type I-IV CCI accounted for 12.90%, 35.48%, 45.16% and 6.45%, respectively. There was no relationship between the CCI and RHF types (p > 0.05). At the end of the follow-up period of 11-26 months with an average of 16 months, the elbow flexion and extension ROM recovered to (147.39 ± 9.84)°, forearm rotation ROM recovered to (168.74 ± 11.70)°, MEPI score recovered to (89.19 ± 4.17), HSS score recovered to (88.74 ± 4.62), VAS score recovered to (0.50 ± 0.57), indicating significant differences compared to preoperative measurements (p < 0.05). According to the MEPI and HSS scores, the excellent and good rate of functional recovery was 100%.

Conclusion: Different types of CCI differ not only in pathology but also in treatment methods. Surgical strategy according to the comprehensive CCI classification introduced in this paper may lead to a satisfactory outcome.