Functional outcome of extra-articular distal humerus fracture fixation using a single locking plate: A retrospective study

Comparative study of mechanical performance of various fixation constructs in multifragmentary distal humeral shaft fracture: a finite element analysis

BACKGROUND

There has been no scientific mechanical assessment demonstrating the optimal fixation technique in multifragmentary fractures of the distal humeral shaft. The purpose of the present study was to compare the biomechanical performance of 5 fixation constructs as used in minimally invasive plating osteosynthesis (MIPO) for distal humeral shaft fractures.

METHODS

Three-dimensional (3D) humerus model with 20 mm distal humeral shaft fracture gap simulating multifragmentary fracture was created from computed tomography data and virtually fixed by 5 fixation techniques as MIPO, i.e., anterior narrow dynamic compression plate (DCP), anterior narrow locking compression plate (LCP), anterior reversed proximal humeral internal locking system (R-PHILOS), extra-articular distal humerus locking compression plate (LCP-EADH), and anteromedial LCP. All constructs were biomechanically tested under 6 loading conditions by means of finite element analysis, i.e., 250-N axial compression, 7.5-N m internal rotation, 7.5-N m external rotation, 10-N m posterior bending, 10-N m valgus rotation, and 10-N m varus rotation. In addition, A 3D model of each construct was fabricated as 3D printed models. Fixations were applied to the 3D printing model which were later mechanically tested to validate the FE results.

RESULTS

EQV stress exhibited on anterior narrow LCP and anterior R-PHILOS were comparable which were lower than other constructs under axial compression and valgus-varus bending. Anterior R-PHILOS produced lower EQV stress than other constructs under internal-external rotation and posterior bending. On the whole, R-PHILOS demonstrated a comparable fracture displacement to those LCP with anterior or anteromedial approaches, that achieved the lowest displacement values. In addition, the experimental mechanical test values shared a correlation with the FE model results.

CONCLUSION

Overall, the anterior R-PHILOS was considered as a potential candidate for multifragmentary distal humeral shaft fractures. It demonstrated efficacious biomechanical performance in terms of implant stress and distal fragment displacement.

Treatment of distal third humeral shaft fractures with posterior minimally invasive plate osteosynthesis (MIPO) with segmental isolation of the radial nerve: minimum one-year follow-up

Background

Open reduction and internal fixation with plate is one of the most widely used treatments for distal third humeral shaft fractures. The purpose of this study was to report the outcomes of the treatment of distal third humeral shaft fractures with posterior minimally invasive plate osteosynthesis (MIPO) with segmental isolation of the radial nerve.

Methods

We performed an observational, retrospective, consecutive, monocentric, continuous multioperator study. We reviewed 22 distal third humeral shaft fractures treated with posterior MIPO in our institution with an extra-articular distal humerus plate from 2018 to 2021. Inclusion was limited to functionally independent patients with displaced fractures involving the junction of the middle and distal thirds of the humerus and minimum 12-month follow-up for implant removal. We assessed clinical outcomes including range of motion; QuickDASH score; Mayo Elbow Performance Score; and Constant-Murley score.

Results

The average follow-up period of the sample was 31.7 ± 11.6 months (range, 15.7-51.3 months). The average elbow flexion and extension were 146.4° ± 7.3° (range, 120°-150°) and -0.7° ± 3.3° (range, -15° to 0°), respectively. The average shoulder anterior flexion, elevation, and abduction were 178.6° ± 3.6° (range, 170°-180°), 179.1° ± 2.9° (range, 170°-180°), and 140.9° ± 14.8° (range, 110°-160°), respectively. The average external rotation was 88.6° ± 6.4 (range, 65°-90°). The mean visual analog scale score for pain was 1.0 ± 1.6 (range, 0-5) and the mean Mayo Elbow Performance Score was 90.5 ± 9.9 (range, 70-100). The mean QuickDASH and Constant-Murley scores were 4.7 ± 6.8 (range, 0-20.5) and 95.5 ± 5.1 (range, 81-100), respectively. Two patients presented with relevant compromise of radial nerve motor function postoperatively (M3 and M2; the more compromised was preoperative injury). All patients recovered radial nerve neuropraxia within six weeks postoperatively. All fractures achieved union. The average anteroposterior and lateral axis were 175.0 ± 3.6 (168.0°-180.0°) and 177.5 ± 2.0 (173.0°-180.0°), respectively. No superficial or deep infection was reported. No cases of re-displacement of fracture, implant failure, or any other implant-related complication in follow-up were reported. No patient required plate withdrawal.

Conclusion

The results of this study demonstrate that the posterior MIPO technique is a reliable option for treating distal third shaft humeral fractures. The radial nerve must be identified and protected in all cases to prevent palsy.

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.

Risk factors for hardware-related complications after extra-articular distal humerus fracture fixation using an anatomical locking plate

PURPOSE

We aimed to identify the incidence and risk factors of hardware-related complications in patients treated with anatomical locking plate fixation for extra-articular distal humerus fractures.

METHODS

From 2013 to 2020, patients with extra-articular distal humerus fractures who underwent open reduction and internal fixation with an extra-articular distal humerus locking plate (EADHP) were retrospectively reviewed and categorized according to the presence/absence of hardware-related complications. Hardware-related complications were defined as the occurrence of skin prominence on the plate and discomfort in activities of daily living. Patient demographics, the lateral condylar angle, lateral body length, shaft-condylar angle of the humerus, and plate length were analyzed.

RESULTS

Of the 29 patients, 10 (34%) did not develop hardware-related complications (group A), whereas 19 (66%) did (group B). Patient demographics did not differ between the groups. However, the number of patients who underwent hardware removal was significantly greater in group B (16/19) than in group A (4/10; p = 0.032). Radiologic assessment revealed no significant difference in the lateral condylar or shaft-condylar angle. However, the lateral body length was greater in group A than in group B (44.5 ± 4.8 vs. 39.5 ± 3.7, p = 0.007). The plate length significantly differed between the groups. Twelve of 19 (63%) patients in group B received short-hole plates (six holes), while nine of ten (90%) patients in group A received long-hole plates (eight holes). In the multivariable analysis, the lateral body length of the distal humerus (p = 0.047, odds ratio = 0.734, 95% confidence interval: 0.542-0.996) and plate length (p = 0.036, odds ratio = 0.076, 95% confidence interval: 0.542-0.996) were associated with hardware-related complications.

CONCLUSIONS

Most patients developed hardware-related complications, particularly with short plates, mainly because of the narrow lateral body length of the distal humerus. Surgeons should be careful to secure EADHP in the appropriate position, especially when short plates are used in patients with narrow lateral body length.

Clinical Outcomes of Single Versus Double Plating in Distal-Third Humeral Fractures Caused by Arm Wrestling: A Retrospective Analysis

Background and Objectives: Arm wrestling is a simple and popular activity among young people that causes distal-third humeral fractures. However, injury to the young population may cause economic loss; therefore, they need to return to work as soon as possible. Accordingly, we aimed to compare radiological and functional outcomes of distal-third humeral fractures caused by arm wrestling treated with double and single plating. Materials and Methods: Thirty-four patients with distal-third humeral fractures caused by arm wrestling were treated between January 2015 and January 2021. They were separated into double- and single-plating groups and treated using a triceps-sparing approach. Regular follow-up was performed to evaluate elbow functionality, range of motion, bone union, and complications; the American Shoulder and Elbow Surgeons score was used for functional assessment. Results: Patients treated with single plating exhibited union rate, union time, and elbow range of motion similar to those of patients treated with double plating; however, they exhibited better pain and functional outcomes (American Shoulder and Elbow Surgeons score) at 2 weeks, 1 month, and 3 months postoperatively (84.50 ± 5.01 vs. 61.70 ± 12.53 at 2 weeks, 96.20 ± 2.63 vs. 84.25 ± 14.56 at 1 month, and 100.00 vs. 94.76 ± 9.71 at 3 months, p < 0.05). The two groups exhibited no significant differences after 1 year (100.00 vs. 98.54 ± 3.99, p < 0.13). The overall complication rate was significantly higher in patients treated with double plating than in those treated with single plating (18.75% vs. 5.56%). Radial nerve palsy was observed in patients in both groups. Conclusions: In patients with distal-third humeral fractures caused by arm wrestling, single plating provides a union rate and elbow range of motion similar to those of double plating, with significantly fewer complications and lower surgical time and blood loss with improved early functional outcomes.

Minimally invasive plate osteosynthesis via posterior approach for type B and C fractures of distal humeral shaft: surgical tactics and a clinical series

The optimal technique and implant for fixation of multifragmentary fractures of the distal humeral shaft remain inconclusive. We describe the use of minimally invasive plate osteosynthesis (MIPO) via posterior approach and extra-articular distal humerus locking compression plate (LCP-EADH) fixation for 18 such fractures. All fractures were united with a mean union time of 17.6 weeks (range 12-20). Transient radial nerve palsy was demonstrated in 2 patients. Six patients had 5° varus angulation and 1 had 5° valgus angulation. Triceps power was Grade 5 in all patients. The mean arc of elbow motion was 127.5 degrees (range 115-140). Six patients had an excellent MEP score and 12 had a good MEP score. As the results, posterior MIPO and LCP-EADH fixation could be an alternative for multifragmentary fractures of the distal humeral shaft, particularly for fractures with a very short distal fragment.

Biomechanical evaluation of a modified proximal humeral locking plate application for distal extra-articular diaphyseal humeral fractures

The extra-articular distal humerus locking plate (EADHP) is widely used for distal extra-articular diaphyseal humeral fracture fixation. However, it occasionally causes skin prominence and discomfort. The upside-down use of a proximal humerus internal locking system (PHILOS) plate is suggested as an alternative option, but it lacks biomechanical evidence. The purpose of this study was to compare the biomechanical performance between two different fixation methods: the modified use of the PHILOS plate on the anterior cortex versus conventional use of an EADHP on the posterior cortex. Twelve pairs of fresh-frozen cadaveric humeri were used and 7 mm gap osteotomy was performed at 50 mm proximal to the lateral epicondyle to simulate an AO/OTA 12-C1.3 fracture type. Single load to failure was measured after five stiffness tests of the plate-bone constructs in anterior/posterior bending, internal/external torsion, and axial compression. There were no significant differences in metrics between the two groups, except for the load to failure in posterior bending, which was significantly higher for PHILOS (1589.3 ± 234.5) compared to EADHP (1430.1 ± 188.6), p < .023. In conclusion, the modified use of the PHILOS plate showed comparable biomechanical performance compared to the conventional EADHP. The new fixation method offers potential clinical advantages, considering the patient's position and surgical approach at the time of surgery as well as postoperative soft tissue irritation. Therefore, this could be an option for distal humeral extra-articular diaphyseal fracture fixation when the use of EADHP is not suitable or preferred.

Functional Outcome and Inflammatory Response of Patients with Extra-Articular Distal Humeral Fractures following Implantation of Anatomically Precontoured Locking Compression Plates through a Posterior Approach

Distal humeral fractures are challenging injuries to surgically correct and account for up to 2% of all adult fractures. Surgical management of extra-articular distal humeral fractures is challenging considering surgical approach, implant selection, and position of the implant owing to the availability of different precontoured implants and plate configurations. Anatomically precontoured locking compression plates (APLCPs) allow the placement of angular stable screws right underneath the reduced joint surface fragments. To date, there is a lack of evidence supporting its superiority to conventional locking plate osteosynthesis (LPO) in treating extra-articular distal humeral fractures. The objective of the study is to evaluate the efficacy and safety of APLCPs in the treatment of extra-articular distal humeral fractures. A total of 100 patients diagnosed with humeral fractures and receiving treatments in our hospital between May 2018 and May 2020 fulfilled inclusion and exclusion criteria and were randomly assigned to LPO and APLCP groups according to the odd-even of the order of hospital admission, 50 cases per groups. Clinical endpoints were assessed including operation time; in-bed time; length of hospital stay; volume of intraoperative blood loss; VSA scores before and 24, 48, and 72 h after surgery; MEPS scores before and 3, 6, and 12 months after surgery; range of motion, flexion, and extension of the elbow; serum levels of CK, CRP, and IL-6; and incidence of complications after surgery. It was found that the APLCP group exhibited shortened operation time and in-bed time, decreased length of hospital stay, and reduced volume of intraoperative blood loss compared to the LPO group (all P < 0.001). The two groups had declined VSA scores concomitant with increased MEPS scores after surgery in a time-dependent manner (P < 0.001). Notably, the VSA scores in the APLCP group were all lower than those in the LPO group at indicated time points (24, 48, and 72 h) after surgery (P < 0.001). Besides, the MEPS scores in the APLCP group were all higher than those in the LPO group at indicated time points (3, 6, and 12 months) after surgery (P < 0.001). It was revealed that the patients receiving extra-articular distal humeral APLCP through posterior approaches exhibited greater ranges of motion, flexion, and extension of the elbow than those receiving LPO after surgery (P < 0.001). The patients receiving extra-articular distal humeral APLCP through posterior approaches exhibited lower serum levels of IL-6, CRP, and CK than those receiving LPO after surgery (IL-6: P=0.007, CRP: P=0.001, CK: P=0.001). The APLCP had a lower total incidence rate of complication than the LPO group (48.00% vs. 18.00%, P=0.003). In conclusion, these data support the notion that the implantation of anatomically precontoured APLCP through a posterior approach allows for improved functional outcomes and attenuated inflammatory response and prevents the incidence of postoperative complications compared to conventional LPO for internal fixation of extra-articular distal humeral fractures.

Anatomic fit of precontoured extra-articular distal humeral locking plates: a cadaveric study

Background

Extra-articular distal humerus locking plates (EADHPs) are precontoured anatomical plates widely used to repair distal humeral extra-articular diaphyseal fractures. However, EADHPs frequently cause distal protrusion and resulting skin discomfort. The purpose of this study was to predict the occurrence of anatomic fit mismatch. We hypothesized that the smaller the humerus size, the greater the anatomic fit mismatch with EADHP.

Methods

Twenty humeri were analyzed in this study. Humeral length and distal humeral width were used as parameters of humeral size. Plate protrusion was measured between the EADHP distal tip and the distal humerus. We set the level of unacceptable EADHP anatomic fit mismatch as ≥10 mm plate protrusion.

Results

A significant negative linear correlation was also confirmed between humeral size and plate protrusion, with a coefficient of determination of 0.477 for humeral length and 0.814 for distal humeral width. The cutoff value of humeral length to avoid ≥10 mm plate protrusion was 293.6 mm (sensitivity, 88.9%; specificity, 81.8%) and for distal humeral width was 60.5 mm (sensitivity, 100%; specificity, 81.8%).

Conclusions

Anatomic fit mismatch in distal humeral fractures after EADHP fixation has a negative linear correlation with humeral length and distal humeral width. For patients with a distal humeral width <60.5 mm, ≥10 mm plate protrusion will occur when an EADHP is used, and an alternative implant or approach should be considered.

Long dorsal "Y-shaped" plate for distal diaphyseal humeral fractures

BACKGROUND

Osteosynthesis of distal diaphyseal humeral fractures is challenging, especially if there is a metaphyseal extension of the fracture line with a butterfly third fragment or if the fracture is bifocal. These fractures put the radial nerve at risk at the time of the fracture and during surgery. We hypothesize that ORIF with a long dorsal Y-plate matching the dorsal aspects of the humeral diaphysis and of the two metaphyseal columns would provide a reliable method of fixation for distal diaphyseal humeral fractures even when there is a metaphyseal extension or bifocal component.

METHODS

Between 2015 and 2019, 17 distal diaphyseal humeral fractures in 17 consecutive patients (14 men, 3 women, mean age 38 years) were operated on with a long "Y-shaped" dorsal plate. There were two bifocal fractures and 11 diaphyso-metaphyseal fractures with butterfly fragments. All 17 patients could be retrospectively followed up clinically and radiographically at a mean follow-up of 25 months (min 4, max 40). Clinical charts included VAS pain, elbow range of motion, QuickDASH, MEPS and subjective elbow value.

RESULTS

Bone healing was observed in all cases. Five patients (29%) had a pre-operative radial nerve palsy. All pre-operative radial nerve palsies but one recovered spontaneously. One complete radial nerve palsy that was not present before the operation was observed after surgery. It recovered spontaneously in four months. One case of post-operative elbow stiffness required a revision. Only one case (5%) showing a complication directly related to the plate (secondary displacement) required revision. Mean post-operative elbow flexion was 134°. Extension deficit averaged 13°. Subjective elbow value, QuickDASH and MEPS averaged respectively 81%, 19 points and 92 points.

DISCUSSION

Currently available plates (long dorsal straight, short dorsal "Y-shaped", long lateral) may have limitations in terms of screw purchase or biomechanical efficiency when ORIF of distal diaphyseal humeral fractures is considered. A long dorsal "Y-shaped" plate is a new alternative which may be successfully used even in the most difficult cases.

CONCLUSION

Our study suggests that a long dorsal "Y-shaped" plate is suitable for distal diaphyseal humeral fractures especially when there is a metaphyseal bifocal or third fragment component.

Outcome of Extra-Articular Distal Humerus Fractures Fixed by Single Column Extra-Articular Distal Humerus Locking Compression Plate Using Triceps Sparing Postero-Lateral Approach

Objective:

To determine the time to radiological union and final functional outcome of fixation of extra-articular distal humeral fractures with extra-artricular distal humerus locking plate.

Methods:

This prospective study was conducted from March 2014 to February 2018 and included extra-articular distal humeral fractures managed by operative fixation using extra-articular distal humerus locking plate. All the fractures were approached using lateral para-tricepetal approach of Gervin, and stabilized with extra-articular distal humerus locking plate with or without lag screws. Time to radiological union was assessed in the follow up and at the final follow up functional outcome was evaluated using Mayo Performance Elbow Score (MEPS). Complications and need for any additional procedures was also recorded.

Results:

A total of 20 patients with mean age of 36.5 years and an average follow up of 17 months were included. The mean time to radiological union was 17.4 weeks (12 to 36 weeks) which included one delayed union that required bone grafting. The mean flexion at elbow was 127o with only one patient having flexion extension arc movement of less than 100o at the final follow up. The average MEPS at final follow up was 94.7±8 with 19 patients having excellent and good results.

Conclusion:

Use of extra-articular distal humeral locking plate using lateral para-tricepetal approach in extra-articular distal humeral fractures allows stable fixation of the fracture to allow early return to function with minimal soft tissue dissection and excellent final functional results and minimum complications.