First-stage scapholunate fusion for the treatment of a chronic lunate dislocation

Abstract

Rationale: Lunate dislocation is a rare injury to the wrist caused by high-energy trauma, and poor prognosis is often associated with missed initial diagnosis. To date, there is no consensus regarding an effective treatment plan for such cases. Patient concerns: Here, we describe the case of a 36-year-old man who presented with lunate dislocation following a delay in diagnosis of over 7 weeks, and further illuminate its diagnosis and treatment. Diagnosis: The diagnosis of chronic lunate dislocation was rendered. Interventions: The patient was treated using reduction via the dorsal approach brachial plexus anesthesia. After the reduction, a headless compression screw fixation was performed for first-stage scapholunate fusion, and Kirschner wire fixation of the lunate-triquetrum-hamate was used to stabilize the distal and proximal carpal rows. Outcomes: The patient was followed up for 1 year and showed wrist function recovered well; radiographic examination showed no lunate dislocation and successful scapholunate bony fusion. A satisfactory outcome was achieved. Lessons: The case study presented here provide evidence that performing an effective first-stage scapholunate fusion is recommended to achieve better therapeutic outcomes for a chronic lunate dislocation. Furthermore, this approach led to a good long-term clinical outcome in our case.

Perilunate Dislocations

“…Although selective wrist arthrodesis is an option for chronic unreduced PLDs, it is typically only indicated in patients with extensive degenerative changes or heavy laborers and rarely reported in the literature 5,51 . Huang et al recently described a case report of a 36-year-old male presenting over 7 weeks from injury and treated with scapholunate fusion and Kirschner wire (K-wire) fixation of the lunotriquetral joint and the hamate-triquetrum joint to stabilize the proximal and distal carpal rows, with a satisfactory outcome at 1 year 52 . Given the other, less morbid treatment options available, selective wrist arthrodesis should be reserved for specific cases, although it is important to consider the occupational needs of the patient in treatment planning.…”

バイク事故による橈骨遠位端骨折に合併した月状骨脱臼の1例(Lunate dislocation with distal radius fracture following a motorcycle accident: a case report)

“…5） 13)。本症例の正面像ではGilula linesの乱れを認めており，月状骨脱臼を疑うことができる。また側面像では月状骨が掌側に転位する“spilled tea cup”と呼ばれる所見が有名であるが，多発外傷では正確な側面像を撮影することが困難な場合も多い 14)。本症例でも，単純X線側面像は正確な位置での撮影ができずspilled tea cupの所見ははっきりしないが，3DCTでは所見が確認できる（Fig. 2b）。また，本症例のように橈骨遠位端骨折を合併する場合には，橈骨の骨折線から手根骨へ向けた外力の加わる方向を想定して手根骨脱臼を想起することも可能といわれる。診断に迷う場合や正確な肢位をとるのが困難な場合は，CT検査が有用であることが報告されており，本疾患を疑うときには積極的に撮影して早期に診断・治療することが重要である 15)。なお，本症例では左橈骨遠位端骨折の既往があるが，画像上変形は指摘できず，後遺症なく経過しており今回の外傷との関連は明らかではない。…”