Is an anteromedial minimally invasive approach for middle and distal third humeral fractures feasible? A cadaveric study and clinical case series

Systematic review of humeral shaft fracture (OTA/AO 12) complicated with iatrogenic radial nerve injury

OBJECTIVES

To compare the iatrogenic radial nerve injury (iRNI) rate of different implant (plate vs. intramedullary nail) and surgical approaches during humeral shaft fracture surgery.

METHODS

The online PubMed database was used to search for articles describing iRNI after humeral fracture with a publication date from Jan 2000 to October 2023. The following types of articles were selected: (1) case series associating with adult humeral shaft fracture, preoperative radial nerve continuity, non-pathological fracture and non-periprosthetic fracture; (2) involving humeral shaft (OTA/AO 12) fractures. Articles where we were unable to judge surgical approach or fracture pattern (OTA/AO 12) were excluded. The data were analyzed by SPSS 27.0 and Chi-square test was performed to identify incidence of iRNI associated with different implant and surgical approaches.

RESULTS

Fifty-four articles with 5063 cases were included, with 3510 cases of the plate, 830 cases of intramedullary nail and 723 cases of uncertain internal fixation. The incidences of iRNI with plate and intramedullary nail were 5.95% (209/3510) and 2.77% (23/830) (p < 0.05). And iRNI incidences of different surgical approaches were 3.7% (3/82) for deltopectoral approach, 5.74% (76/1323) for anterolateral approach, 13.54% (26/192) for lateral approach and 6.68% (50/749) for posterior approach. The iRNI rates were 0.00% (0/33) for anteromedial MIPO, 2.67% (10/374) for anterolateral MIPO and 5.40% (2/37) for posterior MIPO (p > 0.05). The iRNI rates were 2.87% (21/732) for anterograde intramedullary nail and 2.04% (2/98) for retrograde intramedullary nail (p > 0.05). In humeral bone nonunion surgery, the rate of iRNI was 15.00% (9/60) for anterolateral approach, 16.7% (2/12) for lateral approach and 18.2% (6/33) for posterior approach (p  > 0.05).

CONCLUSION

Intramedullary nailing is the preferred method of internal fixation for humeral shaft fractures that has the lowest rate of iRNI. Compared with anterolateral and posterior approaches, the lateral surgical approach had a higher incidence of iRNI. The rate of iRNI in MIPO was lower than that in open reduction and internal fixation.

LEVEL OF EVIDENCE

Level IV.

Modified medial minimally invasive double-plating osteosynthesis techniques for the treatment of distal third diaphyseal fracture of humerus

The optimal surgical approach and placement of plates for the treatment of distal third diaphyseal fracture of the humerus are the subjects of debate. The aim of this retrospective study was to evaluate the clinical and radiographic outcomes of modified medial minimally invasive plate osteosynthesis (MIPO) techniques using a double technique for the treatment of distal third diaphyseal fracture of the humerus. A total of 30 patients with a distal third diaphyseal fracture of the humerus were selected from our hospital. Patients were seen between January 2017 and October 2022. They were treated with a modified medial approach combined with MIPO using a double plate technique. Patient demographics, operation time, bleeding volume, union time, complications, the mean fracture length (FL) and distal cortical length (DCL), and the number of screws in the distal fragment were analyzed. The function of the shoulder and elbow was evaluated using Neer's assessment of the shoulder and Mayo's assessment of the elbow. The FL was 56.1 ± 7.2 mm and the DCL was 38.3 ± 5.3 mm. The mean operative time was 84.8 ± 13.4 min (range 60-110 min). The mean blood loss during surgical treatment was 46.5 ± 10.2 ml (range 30-60 ml). Bone healing was observed in all patients from 10 to 16 weeks (average 12.1 ± 1.7) postoperatively, and one case with poor surgical wound healing was recorded. All the patients had good function of both the shoulder and elbow. The maximum flexibility of the elbow ranged from 130° to 145° (average 138.1 ± 4.8°), with a maximum flexibility straightness ranging from 0° to 5° (average 2.2 ± 1.3°). The Mayo elbow joint function score was 80-100 (average 91.4 ± 5.0). The Neer shoulder joint function score ranged from 85 to 100 (average 92.5 ± 3.9). The modified medial approach was beneficial it did not cause any iatrogenic radial nerve or ulnar nerve injuries. The anterior and the medial side plates are fixed perpendicular to the distal humerus and provide excellent stability at the same time producing better shoulder and elbow joint function.