Complications and outcomes of minimally invasive percutaneous plating for proximal humeral fractures

Functional results of deltoid split minimally invasive osteosynthesis for neer type 3 proximal humerus fractures

We aimed to evaluate the short-term functional and radiological outcomes of the minimally invasive fixation of three-part proximal humerus fractures without using calcar screws. Twenty patients were treated with the minimally invasive approach using locking plate-screws. The relationship between the cephalo-diaphyseal angles and the functional outcomes were evaluated. The mean follow-up time were 22.7 months. The mean Constant-Murley score of the patients was 83.7. The modified Constant-Murley score was excellent in 16 and good in four patients. A statistically significant difference was detected between cephalo-diaphyseal angles. Osteosynthesis with minimally invasive plate-screw and deltoid splitting application is encouraging with its satisfactory results in three-part fractures of the humerus; however, the total complication rate of 35% should not be ignored. In addition, in order to prevent a significant varus collapse and angular loss, the fracture subgroups should be studied in detail and additional measures should be taken based on the fracture type.

Augmented cerclage wire improves the fixation strength of a two-screw construct for humerus split type greater tuberosity fracture: a biomechanical study

Background

Poor functional outcome can result from humeral greater tuberosity (GT) fracture if not treated appropriately. A two-screw construct is commonly used for the surgical treatment of such injury. However, loss of reduction is still a major concern after surgery. To improve the biomechanical strength of screw fixation in GT fractures, we made a simple modification of the two-screw construct by adding a cerclage wire to the two-screw construct. The purpose of this biomechanical study was to analyze the effect of this modification for the fixation of GT fractures.

Materials and methods

Sixteen fresh-frozen human cadaveric shoulders were used in this study. The fracture models were arbitrarily assigned to one of two fixation methods. Group A (n = 8) was fixed with two threaded cancellous screws with washers. In group B (n = 8), all screws were set using methods identical to group A, with the addition of a cerclage wire. Horizontal traction was applied via a stainless steel cable fixed directly to the myotendinous junction of the supraspinatus muscle. Displacement of the fracture fixation under a pulling force of 100 N/200 N and loading force to construct failure were measured.

Results

The mean displacements under 100 N and 200 N traction force were both significantly decreased in group B than in group A. (100 N: 1.06 ± 0.12 mm vs. 2.26 ± 0.24 mm, p < 0.001; 200 N: 2.21 ± 0.25 mm vs. 4.94 ± 0.30 mm, p < 0.001) Moreover, the failure load was significantly higher in group B compared with group A. (415 ± 52 N vs.335 ± 47 N, p = 0.01),

Conclusions

The current biomechanical cadaveric study demonstrated that the two-screw fixation construct augmented with a cerclage wire has higher mechanical performance than the conventional two-screw configuration for the fixation of humeral GT fractures.

Trial registration

Retrospectively registered.

External fixation can be an option for proximal humerus fractures Neer 3-4

Background:

Proximal humeral fractures (PHF) account for 4-6% of all fractures and 25% of humeral fractures. While conservative treatment is the gold standard for simple fractures, there is no consensus about the best treatment choice for complex PHF in the elderly. Recently a new external fixator was introduced in clinical practice for treatment of complex PHF. Aim of the study was to evaluate the functional results of this therapeutic approach.

Methods:

Data were retrospectively analyzed. Inclusion criteria were: three- and four-part PHF according to Neer, treatment with closed reduction and external fixation, normal Abbreviated Mini Mental Test score, independence in the daily living, non-pathological fracture, glenohumeral joint with moderate osteoarthritic changes and availability of clinical and radiological follow-up. For each patient demographic data, comorbidities, surgery time and estimated blood loss were recorded. Clinical and radiological evaluation were performed at 1, 2, 6, 12 months.

Results:

17 patients were enrolled. Mean age was 69.7 years. Fractures were classified according to Neer as type III in 10 cases and type IV in 7 cases. The mean operating time was 22 minutes. Mean Constant score value at follow up was 74 ± 11,52 at 2 months, 82 ± 11,16 at 6 months and 85 ± 9,86 at 12 months.

Conclusion:

These preliminary results show that the studied system is easy to use, minimally invasive, effective in reducing surgical and hospitalization time. The results in terms of functional recovery are encouraging, showing a reduced number of complications. (www.actabiomedica.it)

Outcomes of 188 Proximal Humeral Fractures Treated with a Dedicated External Fixator with Follow-up Ranging from 2 to 12 Years

BACKGROUND

The treatment of a displaced proximal humeral fracture is still a matter of controversy. Minimally invasive techniques are considered promising options. The purpose of this study was to report outcomes at medium to long-term follow-up after surgical treatment with pins stabilized with an external fixator.

METHODS

A total of 235 patients (average age, 64 years [95% confidence interval (CI), 62 to 65 years]) were treated with closed or open reduction and fixation with pins stabilized by an external fixator specifically designed for proximal humeral fractures. The pins were inserted using a "pins-crossing-fracture" or a "pins-bridging-fracture" technique. One hundred and eighty-eight patients had a minimum radiographic and clinical follow-up of 2 years. Outcomes were assessed using the Oxford Shoulder Score (OSS), the subjective shoulder value (SSV), a visual analog scale (VAS) for pain, and, for 155 patients, the Constant score.

RESULTS

Eighty-one (43%) of the 188 patients had a 2-part fracture, 60 (32%) had a 3-part fracture, and 47 (25%) had a 4-part fracture. The reduction was performed with percutaneous maneuvers in 120 shoulders or a deltopectoral approach, in 68. The external fixator was applied using a "pins-crossing-fracture" technique in 133 shoulders and using a "pins-bridging-fracture" technique in 55. At last follow-up, mean clinical scores were as follows: OSS, 42.6 (95% CI, 42 to 44); SSV, 85.5 (95% CI, 83 to 88); and VAS for pain, 1 (95% CI, 0.7 to 1.2). The complication rate at 3 months was 16% (37 of 235). The most frequent complication was pin-track infection (19 of 235, 8%). A total of 50 patients had ≥1 complication (50 of 188, 27%) and 6 (3%) underwent revision surgery. More complications were observed with the "pins-crossing-fracture" technique.

CONCLUSIONS

In our experience, the use of the external fixator has been a valuable option in the treatment of proximal humeral fractures. The complication and revision rates were acceptable. Most of the complications encountered were manageable without revision surgery.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Late screw-related complications in locking plating of proximal humerus fractures: A systematic review

Locking plating is a common surgical treatment of proximal humeral fractures with satisfactory clinical results. Implant-related complications, especially screw-related, have been reported, however, the lack of information regarding their onset, used surgical technique, complexity of the fracture, bone quality etc., prevents from understanding the causes for them. The aim of this systematic review is to identify the potential risk factors for late screw complications by gathering information about the patient characteristics, comorbidities, fracture types, surgical approaches and implant types. A PubMed search was performed using humerus, fractures, bone and locking as keywords in clinical papers written in English. All abstracts and manuscripts on distal or humerus shaft fractures, and those on proximal humerus fractures without any or with only iatrogenic complications were excluded. One hundred studies met the inclusion criteria, resulting in 33% of the reported cases having at least one complication, with 11% of all complications being screw-related. Most of the latter were secondary screw perforations and screw cut-outs, being predominantly linked to poor bone quality, while screw loosening and retraction were found less frequently as a result of locking mechanism failure. Overall, the amount of information for complications was limited and screw perforation was the most frequent screw-related complication, mostly reported in female patients older than 50 years, following four-part or AO/OTA type C fractures and detected four weeks postoperatively. The sparse information in the literature could be an indicator that the late screw complications might have been under-reported and under-described, making the understanding of the screw-related complications even more challenging.

A new risk to the axillary nerve during percutaneous proximal humeral plate fixation using the Synthes PHILOS aiming system

BACKGROUND

Percutaneous aiming arms have been developed to minimize injury during placement of submuscular proximal humerus plates. The purpose of this study was to determine the risk of axillary nerve injury during percutaneous proximal humeral plate fixation using the Synthes PHILOS aiming system.

METHODS

By use of 10 fresh-frozen cadavers (20 shoulders), a 3.5-mm locking compression proximal humeral plate was fixated percutaneously to the humerus through a lateral deltoid-splitting approach using the PHILOS aiming guide. Dissection of the axillary nerve was then carried out, and measurements of its relation to the screw holes in row A through row G of the plate were taken. The lateral acromion-to-axillary nerve distance was also measured.

RESULTS

The axillary nerve traversed row D in every shoulder, whereas it crossed over row C in 11 shoulders and both holes in row E in 16 shoulders. The closest distance to the axillary nerve achieved was 4.5 mm, corresponding to the distal (left) screw in row B. A significant negative correlation was found for the distance from the nerve to the closest proximal and distal screws (row B and row G, respectively) in both right shoulders (ρ = -0.797; 95% confidence interval, -0.916 to -0.548) and left shoulders (ρ = -0.615; 95% confidence interval, -0.831 to -0.237).

CONCLUSION

The axillary nerve traverses rows C, D, and E of the proximal humeral plate using the PHILOS aiming system. Importantly, our study is the first to demonstrate that the axillary nerve crosses over row C. Left-sided plate screws also came in closer proximity to the axillary nerve than right-sided plate screws.

Minimally Invasive Plate Osteosynthesis for Proximal Humerus Fractures: A Retrospective Study Describing Principles and Advantages of the Technique

BACKGROUND

The aim of this study was to evaluate the clinical and radiographic results after minimally invasive plate osteosynthesis (MIPO) for proximal humerus fractures. Potential advantages of this approach include the easier exposure of the greater tuberosity and the limited surgical dissection around the fracture site.

MATERIALS AND METHODS

From October 2011 to March 2016, thirty-nine patients (32 women, 7 men) with a mean age of 64.9 years (range: 48-80) were surgically treated with the MIPO technique for proximal humeral fractures. According to Neer classification, there were 12 two-part, 24 three-part, and 2 four-part fractures and 1 two-part fracture-dislocation; the AO/OTA system was also used to categorize the fractures. The Constant-Murley (CMS) and the Oxford Shoulder (OSS) Scores were used to evaluate shoulder function.

RESULTS

Thirty-four patients were available for clinical and radiographic evaluation at a mean follow-up of 31.8 months (range: 12-54 months). All fractures healed and no postoperative complications occurred. Full recovery of pretrauma activities was reported by 27 patients, while 7 patients presented mild functional limitations. The mean absolute CMS was 75.2 (range: 55-95), the mean normalized CMS was 90.5 (range: 69-107), and the mean OSS was 43.7 (range: 31-48). The only statistically significant correlation was found between the female gender and lower absolute CMS and OSS. Radiographic evaluation revealed varus malunion in 4 cases and valgus malunion in 1 case, while incomplete greater tuberosity reduction was detected in 4 cases. All malunions were related to inadequate reduction at time of surgery and not to secondary displacement.

CONCLUSIONS

MIPO for proximal humeral fractures is an effective and safe surgical procedure. The limited tissue dissection allows minimizing the incidence of nonunion, avascular necrosis, and infection. The technique is not easy, requires experience to achieve mastery, and should be reserved for selected fracture patterns. In our experience, the main advantage of this approach consists in the direct access to the greater tuberosity, thus facilitating its anatomic reduction and fixation.

Minimally Invasive Plate Osteosynthesis Using a Screw Compression Method for Treatment of Humeral Shaft Fractures

Background

This study aims to compare the surgical outcomes of open reduction and internal fixation (ORIF) and minimally invasive plate osteosynthesis (MIPO) using a screw compression method in simple humeral shaft fractures.

Methods

This retrospective study was performed with 50 patients who had surgical interventions for the treatment of simple humeral shaft fractures and had follow-ups of at least 12 months in Ulsan University Hospital between August 2008 and June 2015. Group 1 included 23 patients treated with ORIF and group 2 included 27 patients treated with the MIPO technique using a locking screw plate. The time to clinical/radiographic union, the joint range of motion (ROM), and function were evaluated.

Results

The average time to clinical/radiographic bone union was shorter in group 2 (12.0 ± 3.7 weeks/14.8 ± 2.0 weeks in group 1 and 9.4 ± 1.3 weeks/12.0 ± 3.3 weeks in group 2; p = 0.022/p = 0.034). Shoulder and elbow joint function evaluated by joint ROM and visual analogue scale (VAS), Korean Shoulder Elbow Society (KSS), American Shoulder and Elbow Surgeons (ASES), and the University of California at Los Angeles (UCLA) scores was excellent in both groups. On the average shoulder ROM at 12 months after the operation, group 1 had forward elevation of 160°, external rotation of 30° in adduction and lumbar vertebra 10 level in internal rotation and group 2 had forward elevation of 170°, external rotation of 35° in adduction and lumbar vertebra 9 level in internal rotation. The mean VAS, KSS, ASES, and UCLA scores were 2.8, 87.0 ± 0.9, 89.4 ± 0.9, and 31.0 ± 1.4, respectively, in group 1 and 1.7, 89.1 ± 2.7, 91.0 ± 1.6, and 32.4 ± 3.2, respectively, in group 2. There were statistically significant intergroup differences in VAS score (p = 0.011). There were significantly less postoperative infections in group 2 (three cases, 10.7% in group 1 and 0 case in group 2; p = 0.041) although all of them were superficial infections and well-treated by an average 4-week course of antibiotics (range, 2 to 6 weeks).

Conclusions

MIPO using a screw compression method in simple humeral shaft fractures demonstrated superior efficacy to ORIF in terms of the time to clinical/radiographic union, pain score, and postoperative infection rate.

MIPO of proximal humerus fractures through an anterolateral acromial approach. Is the axillary nerve at risk?

PURPOSE

It is known that shoulder surgery may cause iatrogenic injury to the axillary nerve as a serious complication, but there is little evidence to indicate whether the axillary nerve is at risk of injury during an anterolateral acromial approach for minimally-invasive plate osteosynthesis (MIPO) of proximal humerus fractures. We hypothesised that this surgical method is safe for the axillary nerve and would preserve it from iatrogenic injury.

MATERIALS AND METHODS

We conducted a prospective follow-up cohort study on 49 consecutive patients with proximal humerus fractures who were managed with MIPO through an anterolateral approach. All patients underwent standardised electroneurographic testing, with assessment of amplitudes of evoked compound muscle action potentials (CMAP) and distal motor latencies (DML) of the axillary nerves, pre- and post-operatively. Six weeks after injury, all patients underwent needle electromyographic (EMG) testing of anterior, middle, posterior deltoid, teres minor and paraspinal muscles for detecting abnormal muscle activity as a sign of acute denervation. After six months of physical rehabilitation, patients with axillary nerve injury underwent control electroneurographic testing to check the recovery of neurographic features (CMAP, DML). All nerve measurements were compared to reference values, and between right and left side.

RESULTS

Five patients had a mild-to-moderate traumatic axillary nerve injury before surgery. There were no significant differences between amplitudes of CMAP (p = 0.575) and DML (p = 0.857) pre- and post-surgical procedure.

CONCLUSIONS

These results confirmed safety of this surgical method in the preservation of axillary nerve from iatrogenic injury, but the course of the axillary nerve must be kept in mind.

Minimally invasive plate osteosynthesis with PHILOS plate for proximal humerus fractures

OBJECTIVES

The aim of the present study was to evaluate results, including clinical and radiological outcomes and number of complications, following minimally invasive plate osteosynthesis (MIPO) of proximal humerus fractures, using the PHILOS® proximal humerus internal locking system (Synthes Holding AG, Solothurn, Switzerland).

METHODS

Retrospectively evaluated were 31 patients treated with MIPO (12 male, 19 female; average age: 58.4 years). Four patients had 2-part fractures, 14 patients had 3-part fractures, and 13 patients had 4-part fractures, according to Neer classification. Healing, complications, and head-shaft angle (HSA) were radiographically evaluated. Clinical outcomes were assessed at 1-year follow-up with Constant score.

RESULTS

Average Constant scores for fractured and normal shoulders were 73.2 ± 10.9 and 84.8 ± 5.1, respectively. Varus progression, fracture type, and age had no significant effect on functional outcome. Average postoperative and follow-up HSA's were 130.80 ± 7.70 and 128.80 ± 10.00, respectively. Significant varus progression was observed during follow-up (p = 0.01). Varus progression was more prominent in patients with postoperative HSA < 130° (p < 0.001). Inferomedial calcar screw usage, fracture type, and age had no significant effect on varus progression. Complications included 2 implant failures, 1 case of avascular necrosis (AVN), 1 primary screw cut-out, 1 axillary nerve injury, and 1 radial nerve injury (22.6% overall).

CONCLUSION

MIPO is a safe and effective option for the treatment of proximal humerus fractures, with good functional recovery and fewer complications, which are typically technique dependent. Reduction may be difficult, resulting in varus progression. Another disadvantage is risk of axillary nerve injury. Careful surgical technique and correct implant selection is important in the prevention of nerve injury.

LEVEL OF EVIDENCE

Level IV, Therapeutic study.