Independent destiny of the two tuberosities in patients with complex humeral fractures treated with reverse shoulder arthroplasty and interposition autologous graft

Background Different techniques have been proposed to achieve optimal tuberosity healing in patients with complex humeral head fractures (HHF) treated with reverse shoulder arthroplasty (RSA). The purpose of the study was to compare the healing rate of both tuberosities in patients with complex HHF treated with RSA with and without an interposition autologous grafting technique (IAGT). Secondly, shoulder function in patients with different patterns of tuberosities healing was investigated. Materials and methods A retrospective review study was performed. Eighty-one consecutive patients submitted to RSA for complex HHF were divided into 2 groups: (1) no IAGT and (2) IAGT. Tuberosity healing was radiographically assessed. Constant score (CS) and a 3-grade satisfaction scale were registered. According to the Group B (IAGT group) 4 subgroups were identified (I: healed greater tuberosity [GT]; II: healed GT and lesser tuberosity [LT]; III: reabsorbed GT and LT; IV: healed LT). Results The mean follow-up was 32 months (range 24-66). Eight patients were lost at follow-up. The study group was finally composed of 73 patients (mean age: 76.4, range: 66-82). Group A and B were composed of 37 patients ([9M-28F], mean age: 74.1, range: 69-81) and 36 patients ([7M-29F], mean age: 76.4, range: 66-82), respectively. GT healing was found in 20 patients (54,1%) in Group A and 29 patients (80.6%) in Group B (p = 0.021); LT healing was found in 5 (13,5%) and 10 (27,8%) cases in Group A and B, respectively,(p = 0.034). The mean Constant-Murley score in Group A and B was 60.30 ± 6.41 (range 36-78) and 64.47 ± 8.59 (range 38-81), respectively. No differences were found (p = 0.122). According to Group B: Subgroup I, II and III were composed of 19, 10 and 7 patients, respectively. No isolated LT healing (Subgroup IV) was found. The mean CS in Subgroup I, II and III were 68.0 ± 6 (range: 60-81), 63.1 ± 9.36 (range:52-74) and 60.2 ± 9.73 (range:38-73), respectively(p = 0.262). Subgroup I patients had a significant higher external rotation(p = 0.014), while patients with both healed tuberosities had a significant greater flexion(p = 0.017). 29 (78%) and 32 patients (89%) were very satisfied/satisfied in Group A and B, respectively. Conclusion The IAGT in case of RSA for complex HHF is successful for tuberosity healing and improves patient outcomes. Surprisingly, patients with isolated GT healing had significant higher external rotation than those with both healed tuberosities which, however, maintain significant greater flexion. Further investigations are needed to clarify the role of LT healing during RSA for complex HHF in the elderly.