Axillary nerve palsy after retrograde humeral nailing: clinical confirmation of an anatomical fear

Treatment of Distal Third Humeral Shaft Fracture with Intramedullary Nail Combined with Anterior Minimally Invasive Plate Osteosynthesis

OBJECTIVE

The treatment of distal third humeral shaft fracture is difficult. Studies have shown that anterior minimally invasive plate has lower probability of complication and higher healing rate. However there is no applicable anatomical plate at present. This study is to investigate the clinical effect of intramedullary nail combined with anterior minimally invasive plate in the treatment of distal humeral shaft fractures.

METHODS

The data of 83 patients with lower humerus shaft fracture treated from September 2015 to January 2020 were analyzed. According to different treatment methods, they were divided into two groups: 40 patients were treated with intramedullary nailing combined with minimally invasive anterior plate fixation (group A), and 43 patients were treated with double plate fixation through posterior approach (group B). General preoperative data, operative time, intraoperative blood loss, total incision length, fracture healing time, shoulder and elbow visual analogue scale (VAS) score, Constant-Murley shoulder function score, Mayo elbow function score, and complications were recorded and compared between the two groups. Two independent sample t-tests was used for follow-up, age, BMI, operation time, intraoperative bleeding, total incision length, fracture healing time, Constant-Murley score and Mayo score, and rank sum test was used for VAS score of shoulder and elbow.

RESULTS

There was no significant difference in preoperative general data between the two groups (p > 0.05), indicating comparability. There were no significant differences in operation time, total incision length, fracture healing time, Constant-Murley shoulder function score at the last follow-up, Mayo elbow function score, and shoulder and elbow VAS pain score between 2 groups (p > 0.05). The amount of intraoperative blood loss in observation group was 76.98 ± 16.46, which was significantly less than that in control group, and the difference was statistically significant (p < 0.01). There were no radial nerve injury, musculocutaneous nerve injury, incision infection and fracture nonunion in the observation group. In the control group, four cases of iatrogenic radial nerve injury, three cases of incision infection and three cases of fracture nonunion were found. The complication rate was 23.3% (10/43). There was statistical difference in the incidence of complications between the two groups (p < 0.01).

CONCLUSION

A humeral intramedullary nail combined with an anterior minimally invasive plate in the treatment of distal humeral shaft fracture has the advantages of less soft tissue damage, less blood transfusion, high fracture healing rate and low risk of iatrogenic radial nerve injury, which is an effective method for clinical treatment of this type of fracture.

MRI evaluation of axillary neurovascular bundle: Implications for minimally invasive proximal humerus fracture fixation

Background

Percutaneous fixation of proximal humeral fractures places the axillary nerve and posterior humeral circumflex artery at risk for injury. Safe operative zones for the axillary nerve are described based on external measurements from anatomic landmarks, but no study to date has incorporated advanced imaging to help guide surgical procedures in the region of the axillary neurovascular bundle (ANVB). We sought to define the location and trajectory of the ANVB in relation to osseous landmarks using magnetic resonance imaging (MRI) measurements.

Methods

Retrospective review of 750 consecutive MRI studies was performed with 55 imaging studies meeting inclusion criteria for patient positioning, image alignment, and quality. Five measurements were performed including the distance from mid-lateral acromion to lateral ANVB, mid-lateral acromion to medial ANVB, greater tuberosity to lateral ANVB, vertical distance between inferior anatomic neck and lateral ANVB, and angle the ANVB crosses the humerus. Height, gender, and age were recorded. Analysis was performed using ANOVA and Pearson correlation tests.

Results

The lateral ANVB was below the inferior articular margin of the humeral head by an average of 12.9 ± 3.9 mm and within a 22 mm window. It was an average of 57.4 ± 5.1 mm from the lateral mid-acromion, and 34.7 ± 4.3 mm below the greater tuberosity. The angle formed by the ANVB crossing the humerus averaged 19.5 ± 3.9 degrees upward from medial to lateral. Height and gender directly impacted measurements.

Conclusions

The use of the inferior humeral head articular margin provides a radiographic landmark to aid intraoperative lateral ANVB assessment which may be helpful during percutaneous fracture fixation.

Retrograde Intramedullary Nailing for Humerus Fracture in a Supine Position: Performing an Unfamiliar Procedure in a Familiar Position

Intramedullary (IM) nailing for humeral shaft fracture has provided excellent outcomes in terms of fracture biology and cosmetic appearance because of the relatively small incision involved. However, antegrade nailing causes issues such as iatrogenic rotator cuff injury. Retrograde nail fixation method could avoid cuff injury, but has shortcomings such as the need for the prone or lateral decubitus position during surgery. We report that the retrograde IM nail fixation technique performed in a supine position and some ancillary techniques for minimizing scars or complications can provide the advantages of both retrograde nailing and supine position during surgery.

Causes of Secondary Radial Nerve Palsy and Results of Treatment

Background

The aim of this study was to analyze the causes that lead to secondary damage of the radial nerve and to discuss the results of reconstructive treatment.

Material/Methods

The study group consisted of 33 patients treated for radial nerve palsy after humeral fractures. Patients were diagnosed based on clinical examinations, ultrasonography, electromyography, or nerve conduction velocity. During each operation, the location and type of nerve damage were analyzed. During the reconstructive treatment, neurolysis, direct neurorrhaphy, or reconstruction with a sural nerve graft was used. The outcomes were evaluated using the Medical Research Council (MRC) scales and the quick DASH score.

Results

Secondary radial nerve palsy occurs after open reduction and internal fixation (ORIF) by plate, as well as by closed reduction and internal fixation (CRIF) by nail. In the case of ORIF, it most often occurs when the lateral approach is used, as in the case of CRIF with an insertion interlocking screws. The results of the surgical treatment were statistically significant and depended on the time between nerve injury and revision (reconstruction) surgery, type of damage to the radial nerve, surgery treatment, and type of fixation. Treatment results were not statistically significant, depending on the type of fracture or location of the nerve injury.

Conclusions

The potential risk of radial nerve neurotmesis justifies an operative intervention to treat neurological complications after a humeral fracture. Adequate surgical treatment in many of these cases allows for functional recovery of the radial nerve.

Complications after interlocking intramedullary nailing of humeral shaft fractures

INTRODUCTION

IM nails have gained popularity for stabilization of humeral shaft fractures (HSF). The initial enthusiasm was tempered by a number of specific complications and thus indications need to be re-evaluated.

PATIENTS AND METHODS

This retrospective study includes 111 patients with HSF subjected to a treatment protocol of IM fixation with first and second generation of humeral nails. Antegrade approach was used in 105 (94.5%) and retrograde in 6 (5.5%) patients. Reaming was performed in 51 (45.9%) fractures. The study covers a period of 10 years. Mean follow-up time was 3.5 (1-6) years. This investigation is directed at technical errors and complications, especially those corrected by secondary surgery.

RESULTS

We registered 52 (46.85%) intra-operative complications in 40 (36.04%) patients, on average 1.3 per patient. The most common were: distraction n=5 (4.5%), long proximal locking screws n=9 (8.1%), additional diaphyseal fracture n=7 (6.3%) and countersinking of the nail in the humeral head n=8 (7.2%). The number of postoperative complications was 40 (36.0%) related to 19 (17.1%) patients. Technical errors, such as distraction, longer nail and additional fractures have affected time to union and resulted in chronic shoulder pain. 36 (32.5%) secondary surgeries were needed to address these problems. When first generation nails are used, the intra-operative complication related risk increases 1.58 times, and the postoperative complication related risk is 1.67 times higher compared to second generation nails. According to Constant-Murley score excellent and very good functional results were achieved in 93 (83.78%) patients. While reaming did not influence the clinical results for both nail generations, overall better results were achieved with second generation nails. Postoperative shoulder pain has been registered in 18 (16.2%) patients.

CONCLUSION

We registered a number of technical errors and complications, which we consider technique specific. The analysis and avoidance of these complications, related only to IM nailing of the humerus, will allow IM nails to successfully bridge the gap between functional bracing and plating.

Minimally invasive plate osteosynthesis for humeral shaft fracture: a reproducible technique with the assistance of an external fixator

BACKGROUND

Minimally invasive plate osteosynthesis (MIPO) has become a popular option for treatment of humeral shaft fractures. However, indirect reduction might risk unpromising results, with mal-alignment/mal-union or nonunion. The purpose of this study was to describe a reproducible MIPO technique that used an external fixator during the procedure as a tool for reduction and maintenance, and to assess the outcomes in patients with humeral shaft fracture.

METHODS

Of 31 consecutive cases of humeral shaft fracture in 30 patients, 29 were included in this study. There were seven simple (type A) and 22 comminuted (type B or C) fractures. After the insertion of one Schanz pin on each proximal and distal humerus, a provisional reduction was achieved by connecting the pins with a monolateral external fixator. The MIPO procedure was then performed over the anterior aspect of the humerus. To evaluate the efficacy of the provisional reduction by external fixator, coronal and sagittal alignments were assessed. We also assessed bony and functional results, including complications, from this technique.

RESULTS

There was no case of mal-union >10°, and mean angulation was 1.3° (range 0°-9°) in the coronal plane and 1.2° (range 0°-8°) in the sagittal plane. Twenty-eight of 29 fractures were united, including three delayed unions, with a mean union time of 19.1 weeks (range 12.3-38.4 weeks) and a mean follow-up of 20.8 months (range 13.5-31.0 months). There was one hypertrophic nonunion that healed after fixing with two additional screws. Except one patient with associated injury in the elbow, all patients recovered to pre-injury joint motion. There were two cases of postoperative radial nerve palsy that both recovered completely. We attributed them to manipulation, and not to the Schanz pins or plate fixation.

CONCLUSIONS

Surgical treatment of humeral shaft fractures with external fixator-assisted reduction and MIPO resulted in excellent reductions and high union rates.

Anatomic study of the axillary nerve in a Chinese cadaveric population: correlation of the course of the nerve with proximal humeral fixation with intramedullary nail or external skeletal fixation

INTRODUCTION

The axillary nerve can be injured during external skeletal fixation with Schanz screws or proximal locking screws of intramedullary nails. Being aware of the axillary nerve's anatomic relationship to the proximal humerus is vital for avoiding complications.

METHODS

We investigated the relationship of the axillary nerve to surrounding bony landmarks by studying 88 axillary nerves in 44 embalmed cadaveric adult Chinese males. These measurements were then compared with the results from a similar study among Caucasians using the same reference points.

RESULTS

We identified three significantly different parameters between our Chinese and the previously studied Caucasian subjects (P ≤ 0.05): the distances from the superior aspect of the humeral head to the axillary nerve (D1) (5.2 ± 0.7 vs. 6.09 ± 0.65 cm, respectively); surgical neck to axillary nerve (D2) (2.0 ± 0.7 vs. 1.72 ± 0.84 cm); and humeral length (D3) (29.0 ± 2.2 vs. 35.25 ± 5.7 cm). The D1 distance ranged from 4.0 to 6.7 cm; the D2 distance ranged from 1.0 to 4.1 cm; and the entire humeral length (D3) ranged from 23.3 to 33.3 cm. Iatrogenic injury to the axillary nerve could be reduced by placing pins and screws in proper directions using portable C-arm fluoroscopic guidance, drill-guided protective systems, and a mini-open-incision with muscle spreading and drill protective systems directly placed on the bone.

CONCLUSION

Because of physical variability among individual patients and populations, surgeons should consider the possible courses of the axillary nerve when treating proximal humeral fractures.

Diaphyseal humeral fractures and intramedullary nailing: Can we improve outcomes?

While intramedullary nailing has been established as the treatment of choice for diaphyseal fractures of the femur and tibia, its role in the management of diaphyseal humeral fractures remains controversial. The reasons include not only the complicated anatomy and unique biomechanical characteristics of the arm but also the fact that surgical technique and nail designs devised for the treatment of femoral and tibial fractures are being transposed to the humerus. As a result there is no consensus on many aspects of the humeral nailing procedure, e.g., the basic nail design, nail selection criteria, timing of the procedure, and the fundamental principles of the surgical technique (e.g., antegrade/retrograde, reamed/unreamed, and static/dynamic). These issues will be analyzed and discussed in the present article. Proposals aiming to improve outcomes include the categorization of humeral nails in two distinct groups: "fixed" and "bio", avoidance of reaming for the antegrade technique and utilization of "semi-reaming" for the retrograde technique, guidelines for reducing complications, setting the best "timing" for nailing and criteria for selecting the most appropriate surgical technique (antegrade or retrograde). Finally, suggestions are made on proper planning and conducting clinical and biomechanical studies regarding the use of intramedullary nailing in the management of humeral shaft fractures.

Review of the surgical anatomy of the axillary nerve and the anatomic basis of its iatrogenic and traumatic injury

The axillary nerve is invariably reported to be one of the most commonly injured nerves during surgical procedures of the shoulder, and the importance of protecting it cannot be overemphasized. Many researchers have tried to identify safe regions, but the results vary among published studies. The axillary nerve may also be injured during acute trauma to the shoulder or by chronic repeated trauma as has been described in the quadrilateral space syndrome. The nerve injury may occur together with shoulder dislocation and rotator cuff tear, thus comprising the so-called "unhappy triad" of the shoulder joint. Simple attention to potential variations in the origin and course of the axillary nerve and its relationship to the shoulder capsule and having a precise knowledge of "safe zones" during operations can enhance clinical outcomes. The objective of this review, therefore, is to discuss the surgical anatomy of the axillary nerve and further emphasize the clinical importance of the its injury following shoulder trauma.

A new modular nail for the diaphyseal fractures of the humerus

Over a period of 5 years, 63 traumatic and eight pathological diaphyseal humeral fractures were treated with a new modular humeral nail. The nail is cannulated, square in shape--with concave sides--and has two different extensions that can be used with either the antegrade or the retrograde approach. Adequate rotational and axial stability is provided without the need for distal locking screws in the majority of fractures, while the need for proximal locking screws during the antegrade procedure is abolished. This study aims to present the 'Garnavos' nail and the results of its use, along with proposals and guidelines that should be considered whenever intramedullary nailing is selected for the treatment of diaphyseal humeral fractures.