Clinical classification and treatment strategy of hamate hook fractures

Abstract

Objective To explore the clinical classification of hamate hook fractures and the treatment strategies for different types of fractures.Methods Twelve cases of hamate hook fractures were retrospectively reviewed.According to the fracture sites and the prognosis,the hamate hook fractures were classified into 3 types.Type Ⅰ referred to an avulsion fracture at the tip of the hamate hook,while type Ⅱ presented as a fracture in the middle part of the hanate hook,and type Ⅲ represented a fracture at the base of the hamate hook.According to such a classification,in our series there was only 1 case of type Ⅰ,7 cases of type Ⅱ,and 4 cases of type Ⅲ.Threecases were treated conservatively,while 4 cases were treated with open reduction and internal fixation and another 5 cases with hamate hook excision.Pre-operative ulnar nerve injury co-existed in 3 cases (2 cases of type Ⅱ and 1 case of type Ⅲ).Flexor digiti minimi tendon injury co-existed in 2 cases (type Ⅱ),while pisiform-triquetral joint dislocation co-existed in 1 case (type Ⅱ).The results were evaluated with respect to the functional recovery,recovery time,the relationship between clinical classification,pre-operative complications and the treatment outcomes.Results The average follow-up time of this group was (8.4 ± 3.9) months,ranging from 4 to 16 months.Among the 7 cases treated with conservative measures or open reduction and internal fixation 2 had fracture non-union.Both cases were type Ⅱ fractures.The other 5 cases all achieved bone union.All the patients were satisfied at time of the last follow-up.Their pain scale and grip strength improved significantly after the treatment.All the pre-operative complications were relieved.The recovery time of patients treated with hamate hook excision was significantly shorter than those treated with other two methods.The incidences of both pre-operative complications and non-union in type Ⅱ fractures were higher than those in type Ⅰ and type Ⅲ fractures.Conclusion The general therapeutic effects of hamate hook fractures are quite satisfactory.Type Ⅰ and type Ⅲ fractures without displacement can be treated with conservative measures.Type Ⅲ fractures with displacement can be treated with open reduction and internal fixation.Type Ⅱ fractures,due to the higher complication incidence,should be treated with hamate hook excision. Key words: Hamate bone; Fractures,bone; Treatment outcome; Follow-up studies; Clinical classification