Biomechanical comparison of tension band wiring and plate fixation with locking screws in transverse olecranon fractures

Mini-fragment plate fixation after olecranon osteotomy for distal humerus fractures

PURPOSE

Although olecranon osteotomies are helpful for distal humerus visualization, traditional methods of fixation are commonly irritating for patients and require hardware removal. Recent studies have shown lower hardware removal rates for medullary screw constructs and 3.5-mm plates, but no studies have investigated the use of 2.7-mm plates for olecranon osteotomy fixation. The purpose of this study is to report on the outcomes of single 2.7-mm mini-fragment plate fixation of olecranon osteotomies for distal humerus intra-articular fractures.

METHODS

Patients who sustained an intra-articular distal humerus fracture, as identified by Current Procedural Terminology codes, were reviewed retrospectively over a 5-year study period (2016-2020) at a single level 1 trauma center after institutional review board approval. Only patients who underwent an olecranon osteotomy for distal humerus visualization during their definitive operation and that was subsequently fixed with a single 2.7-mm plate were included. Primary outcomes were implant removal and osteotomy union. Secondary outcomes included indications for implant removal, implant failure, infection, and revision surgery. Hardware removal rates were compared to historically reported rates in the literature. χ2 vs. Fisher exact tests were used to compare fixation groups based on number of patients in each cohort (5 or less was used for the cutoff for Fisher exact test).

RESULTS

Thirty-eight patients were included in the final analysis. The average age was 50 years (standard deviation [SD] 18), 58% (22 patients) were female, and the average follow-up time was 9.7 months (SD 5). All patients with mini-fragment plate fixation went on to union of their olecranon osteotomy. Three patients (7.8%) had their olecranon hardware removed for all causes: 1 for revision open reduction and internal fixation (ORIF), 1 for irritation, and 1 removal during concomitant capsulectomy and manipulation. There was a 21% (8 patients) revision surgery rate in the cohort but only 3 of those were for issues related to the olecranon osteotomy. One patient required revision ORIF of the olecranon osteotomy for hardware loosening. Compared with other fixation constructs, mini-fragment plates had a lower removal rate than tension band wiring (P = .0002) and 3.5-mm plates (P = .05) and similar among medullary screws ± wires. Nonunion rates were similar between all constructs (P = .07).

CONCLUSION

Single 2.7-mm mini-fragment plate fixation of olecranon osteotomies for distal humerus fractures is safe and effective with low rates of revision, hardware removal, and nonunion. This type of fixation should be considered when treating intra-articular distal humerus fractures that require an olecranon osteotomy.

Is headless screw a valid alternative for the fixation of Chevron olecranon osteotomy? A biomechanical comparison of 4 fixation methods

BACKGROUND

Chevron osteotomy is a popular technique for repairing complex distal humerus intra-articular fractures. However, refixation presents challenges like hardware prominence and soft tissue damage. Headless cannulated screws are gaining popularity for fixation due to better bone purchase and less irritation. This study aims to compare different fixation strategies with headless screws for Chevron osteotomy fixation.

METHODS

This study utilized 32 polyurethane foam ulna specimens for biomechanical testing. The Chevron osteotomy was performed with an oscillating saw for all specimens. Four different techniques were used for refixation: modified tension band wire fixation, plate-screw fixation, cannulated screw fixation, and headless cannulated screw fixation. The constructs were mounted to the testing machine, simulating the elbow in 90 degrees of flexion. All specimens were tested under axial traction. Displacements at 350N and 500N and loads at the failure were recorded.

RESULTS

At the load of the implant failure, headless cannulated screw fixation revealed higher force values when compared to the other constructs, and modified tension band wire fixation showed lower force values compared to the other 3 groups (P < .001). The headless cannulated screw fixation group showed no significant differences in osteotomy displacements when tested to a 350N load. There were no significant differences in displacements at a 500N load between the four groups (P = .275).

CONCLUSION

This study suggests that headless cannulated screw fixation is a viable and effective option for Chevron osteotomies. Headless cannulated screw fixation makes it a promising alternative to traditional fixation methods. This technique may be a more reliable fixation technique during daily activities and moderate elbow motions, indicating that it has the potential to succeed.

Evaluation of Intramedullary Olecranon Screw Fixation for Simple Olecranon Fractures: A Biomechanical Study

PURPOSE

The purpose of this study was to biomechanically evaluate the stability of the 6.5 mm intramedullary (IM) olecranon screw compared to locking compression plate fixation for Orthopedic Trauma Association/AO Foundation (OTA/AO) 2U1B1 olecranon fractures under cyclic range of motion of the elbow.

METHODS

Twenty paired elbows were randomized to either IM olecranon screw or locking compression plate fixation of a simulated OTA/AO 2U1B1 fracture. Pullout strength was tested by increasing force applied to the triceps and proximal fragment. Fracture gap displacement was measured using differential variable reluctance transducers as the elbow was cycled through a 135° arc of motion using a servohydraulic testing system.

RESULTS

Analysis of variance revealed significant interaction between group and load on fracture distraction after the 500th cycle in three settings: between the plate at 5-pound load and screw at 35-pound load, the screw at 5-pound load and screw at 35-pound load, and between the plate at 15-pound load and screw at 35-pound load. The difference in the rate of failure between plate (2 of 80 samples) and screw (4 of 80 samples) was not statistically significant.

CONCLUSIONS

For OTA/AO 2U1B1 olecranon fractures, a single 6.5 mm IM olecranon screw demonstrated similar stability when compared to the locking compression plates throughout range of motion testing.

CLINICAL RELEVANCE

From a biomechanical perspective, 6.5 mm IM screws and locking compression plates have similar ability to maintain fracture reduction following simulated elbow range of motion exercises in OTA/AO 2U1B1 fractures, giving surgeons another option in the management of these fractures.

The effect of Ding's screws and tension band wiring for treatment of olecranon fractures: a biomechanical study

Although tension band wiring (TBW) is popular and recommended by the AO group, the high rate of complications such as skin irritation and migration of the K-wires cannot be ignored. Ding's screw tension band wiring (DSTBW) is a new TBW technique that has shown positive results in the treatment of other fracture types. The objective of this study was to evaluate the stability of DSTBW in the treatment of olecranon fractures by biomechanical testing. We conducted a Synbone biomechanical model by using three fixation methods: DSTBW, intramedullary screw and tension band wiring (IM-TBW), and K-wire TBW, were simulated to fix the olecranon fractures. We compared the mechanical stability of DSTBW, IM-TBW, and TBW in the Mayo Type IIA olecranon fracture Synbone model using a single cycle loading to failure protocol or pullout force. During biomechanical testing, the average fracture gap measurements were recorded at varying flexion angles in three different groups: TBW, IM-TBW, and DSTBW. The TBW group exhibited measurements of 0.982 mm, 0.380 mm, 0.613 mm, and 1.285 mm at flexion angles of 0°, 30°, 60°, and 90° respectively. The IM-TBW group displayed average fracture gap measurements of 0.953 mm, 0.366 mm, 0.588 mm, and 1.240 mm at each of the corresponding flexion angles. The DSTBW group showed average fracture gap measurements of 0.933 mm, 0.358 mm, 0.543 mm, and 1.106 mm at the same flexion angles. No specimen failed in each group during the cyclic loading phase. Compared with the IM-TBW and TBW groups, the DSTBW group showed significant differences in 60° and 90° flexion angles. The mean maximum failure load was 1229.1 ± 110.0 N in the DSTBW group, 990.3 ± 40.7 N in the IM-TBW group, and 833.1 ± 68.7 N in the TBW group. There was significant difference between each groups (p < 0.001).The average maximum pullout strength for TBW was measured at 57.6 ± 5.1 N, 480.3 ± 39.5 N for IM-TBW, and 1324.0 ± 43.8 N for DSTBW. The difference between maximum pullout strength of both methods was significant to p < 0.0001. DSTBW fixation provides more stability than IM-TBW and TBW fixation models for olecranon fractures.

Efficacy comparison of Kirschner-wire tension band and anchor loop plate in treatment of olecranon fracture

Objective: This study aimed to introduce a new surgical method for the fixation of olecranon fractures, and to compare the biomechanical stability and clinical efficacy of Kirschner wire tension band and anchor loop plate (ALP) in the treatment of olecranon fractures. Methods: A finite element model was established to analyze the mechanical properties of Kirschner wire tension and anchor loop plate fixation for olecranon fracture. The clinical data of 53 patients with olecranon fractures admitted to our hospital from March 2016 to October 2021 were retrospectively analyzed. Among them, 22 cases were fixed with an anchor loop plate (ALP group), and 31 patients were fixed with the Kirschner wire tension band technique. By reviewing the medical records and follow-up results, the final elbow mobility, secondary surgery, postoperative complications and elbow function recovery Mayo score and DASH score were compared between the two groups. Results: The biomechanical analysis of the finite element model showed that under the load of 120 N, the maximum displacement of the Kirschner wire group was 1.09 times that of the ALP group, the maximum stress of the Kirschner wire group was 1.33 times that of the ALP group, and the maximum stress of the olecranon proximal bone of the Kirschner wire group was 2.17 times that of the ALP group. Under the load of 200 N, the maximum displacement of the Kirschner wire group was 1.19 times that of the ALP group. The overall maximum stress of the Kirschner wire group was 1.59 times that of the ALP group, and the maximum stress of the proximal olecranon bone of the Kirschner wire group was 1.99 times that of the ALP group. The average follow-up time of the Kirschner wire and anchor loop plate groups was similar (p > 0.05). The average age of the two groups was identical (p > 0.05). The final elbow mobility in the anchor loop plate group was significantly greater than in the Kirschner wire group (p < 0.05). The Mayo score of the anchor loop plate group was substantially higher than that of the Kirschner wire group at 3 and 12 months after operation (p < 0.05), and the DASH score was significantly lower than that of the Kirschner wire group (p < 0.05). Postoperative complications in the two groups: 1 case (4.5%) in the anchor loop plate group had difficulties with internal fixation stimulation, and no infection occurred; in the Kirschner wire group, 5 cases (16.1%) had complications of internal fixation stimulation, and 1 patient (3.2%) had an infection. Conclusion: The model of olecranon fracture fixed by anchor loop plate and Kirschner wire tension technique was tested under 120 and 200 N tension, and no damage was found, indicating that the newly designed anchor loop plate was safe in mechanical structure. The biomechanical stability of the anchor plate technique is more stable, so it is not easy to have postoperative complications such as fracture block cutting and internal fixation failure. And the secondary operation rate and elbow function have better results. This technique is an effective method for the treatment of olecranon fractures.

The effect of ding's screw and tension band wiring for treatment of olecranon fractures: a finite element study

BACKGROUND

Tension band wiring (TBW) is a common surgical intervention for olecranon fractures. However, high rate of complications such as loss of reduction, skin irritation, and migration of the K-wires were reported up to 80%. Ding's screw tension band wiring (DSTBW) is a new TBW technique that has shown positive results in the treatment of other fracture types. The objective of this study was to evaluate the stability of DSTBW in the treatment of olecranon fractures by finite element analysis.

METHOD

We used Ding's screw tension band fixation (DSTBW) and K-wire tension band fixation (TBW) to establish a finite element model to simulate and fix olecranon fractures. The stress distribution, opening angle, twisting angle, and pullout strength of K-wires or screws were analyzed and compared.

RESULTS

The maximum von Mises stress was observed on the internal fixation for 90° elbow motion in both groups. The von Mises value of the screw in DSTBW was 241.2 MPa, and the von Mises value of k-wire in TBW was 405.0 MPa. Opening angle: TBW was 0.730° and DSTBW was 0.741° at 45° flexion; TBW was 0.679° and DSTBW was 0.693° at 90° flexion. Twisting angle: TBW was 0.146° and DSTBW was 0.180° at 45° flexion; TBW was 0.111° and DSTBW was 0.134° at 90° flexion. The pullout strength of DSTBW was significantly higher than that of TBW. Maximum pullout strength of Ding's screw was 2179.1 N, maximum pullout strength of K-wire was 263.6 N.

CONCLUSION

DSTBW technology provides stable fixation for olecranon fractures, reducing the risk of internal fixation migration and failure.

Biomechanical comparison of tension band suture fixation and tension band wiring in olecranon fractures

PURPOSE

Traditional tension band wire fixation (TBWF) of olecranon fractures is associated with high revision rates due to implant-related complications. The purpose of the study was to compare the strength of fixation in olecranon fractures between TBWF and an all-suture based technique.

METHODS

A transverse fracture was created in 20 paired fresh-frozen human cadaveric elbows. Fractures were randomly (alternating right-left) assigned for fixation with either tension band suture fixation (TBSF) or TBWF. The elbow was fixed in 90° of flexion and underwent cycling loading by pulling the triceps tendon to 300 N for 200 cycles. Fracture displacement was optically recorded using digital image correlation (DIC). Finally, load-to-failure was assessed by a monotonic pull to 1000 N and failure mechanism was recorded.

RESULTS

Two specimens in the TBSF group were excluded from the cycling loading analysis due to technical difficulties with the DIC. After cyclic loading, median (min-max) fracture displacement was 0.28 mm (0.10-0.44) in the TBSF group and 0.18 mm (0.00-1.48) in the TBWF group (p = 0.315). No difference was found between the two groups in the repeated measures analysis of variance (p = 0.329). In the load-to-failure test, 6/10 specimens failed in the TBSF group (median load-to-failure 791 N) vs. 8/10 in the TBWF group (median load-to-failure 747 N). The TBSF constructs failed due to fracture of the dorsal cortex, suture breakage or triceps failure. The TBWF constructs failed due to breakage of the wire.

CONCLUSION

There was no difference in fixation strength between the TBWF and TBSF constructs. Our findings suggest TBSF to be a feasible alternative to TBWF and we hypothesize that a non-metallic implant may have fewer implant-related complications.

LEVEL OF EVIDENCE

Basic science study.

Locked Tension Band Wiring for Mayo IIA Olecranon Fractures: Modified Surgical Technique and Retrospective Comparative Study of Clinical Outcomes and Cost-effectiveness with Locking Plate

Background: Tension band wiring (TBW) has traditionally been used for simple olecranon fractures, but due to its many complications, locking plate (LP) is increasingly being employed. To reduce the complications, we developed a modified technique for olecranon fracture repair, locked TBW (LTBW). The study aimed to compare (1) the frequency of complications and re-operations between LP and LTBW techniques, (2) clinical outcomes and the cost efficacy. Methods: We retrospectively evaluated data of 336 patients who underwent surgical treatment for simple and displaced olecranon fractures (Mayo Type ⅡA) in the hospitals of a trauma research group. We excluded open fractures and polytrauma. We investigated complication and re-operation rates as primary outcomes. As secondary outcomes, Mayo Elbow Performance Index (MEPI) and the total cost, including surgery, outpatients and re-operation, were examined between the two groups. Results: We identified 34 patients in the LP group and 29 patients in the LTBW group. The mean follow-up period was 14.2 ± 3.9 months. The complication rate in the LTBW group was comparable to that in the LP group (10.3% vs. 17.6%; p = 0.49). Re-operation and removal rates were not significantly different between the groups (6.9% vs. 8.8%; p = 1.000 and 41.4% vs. 58.8%; p = 1.00, respectively). Mean MEPI at 3 months was significantly lower in the LTBW group (69.7 vs. 82.6; p < 0.01), but mean MEPI at 6 and 12 months were not significantly different (90.6 vs. 85.2; p = 0.06, 93.9 vs. 95.2; p = 0.51, respectively). The mean cost/patient of the total cost in the LTBW group were significantly lower than those in the LP group ($5,249 vs. $6,138; p < 0.001). Conclusions: This study showed that LTBW achieved clinical outcomes equivalent to those of LP and was significantly more cost effective than LP in the retrospective cohort. Level of Evidence: Level III (Therapeutic).

Olecranon fractures : current treatment concepts

Despite being one of the most common injuries around the elbow, the optimal treatment of olecranon fractures is far from established and stimulates debate among both general orthopaedic trauma surgeons and upper limb specialists. It is almost universally accepted that stable non-displaced fractures can be safely treated nonoperatively with minimal specialist input. Internal fixation is recommended for the vast majority of displaced fractures, with a range of techniques and implants to choose from. However, there is concern regarding the complication rates, largely related to symptomatic metalwork resulting in high rates of implant removal. As the number of elderly patients sustaining these injuries increases, we are becoming more aware of the issues associated with fixation in osteoporotic bone and the often fragile soft-tissue envelope in this group. Given this, there is evidence to support an increasing role for nonoperative management in this high-risk demographic group, even in those presenting with displaced and/or multifragmentary fracture patterns. This review summarizes the available literature to date, focusing predominantly on the management techniques and available implants for stable fractures of the olecranon. It also offers some insights into the potential avenues for future research, in the hope of addressing some of the pertinent questions that remain unanswered.Cite this article: Bone Joint J 2023;105-B(2):112-123.

Olecranon Fractures: A Critical Analysis Review

»

Olecranon fractures account for 10% of all elbow fractures and are more likely to result from a low-energy injury. A displaced fracture with a stable ulnohumeral joint (Mayo type 2) is the most common type of injury.

»

The management of an isolated olecranon fracture is based on patient factors (age, functional demand, and if medically fit to undergo surgery) and fracture characteristics including displacement, fragmentation, and elbow stability.

»

Nonoperative management can be successfully used in undisplaced fractures (Mayo type 1) and in displaced fractures (Mayo type 2) in frail patients with lower functional demands.

»

Patients with displaced olecranon fractures with a stable ulnohumeral joint without significant articular surface fragmentation (Mayo type 2A) can be managed with tension band wiring, plate osteosynthesis (PO), intramedullary fixation, or suture repair.

»

PO is advocated for multifragmentary fractures and fractures that are associated with ulnohumeral instability. It is essential to consider the variable anatomy of the proximal ulna during surgery.

Biomechanical comparison of the new cross-locking intramedullary nail with tension band wiring for transverse olecranon fractures

BACKGROUND

In the treatment of transverse olecranon fractures, complicated tension band wiring (TBW) has high rates of re-operations. Besides, plate fixation (PF) and TBW both have large surgical incisions and soft-tissue irritation. Therefore, the new cross-locking intramedullary nail (CIN) with easy handling and minimally invasive features is significantly advantageous. The goal of this study was to biomechanically compare CIN with TBW for fixing transverse olecranon fracture.

METHODS

The transverse olecranon fracture models were created with 15 fresh-frozen cadaveric ulnae which were randomly divided into 3 groups: one group for TBW fixation, another for CIN fixation with 1 conical locking screw (CIN-1), and the last for CIN fixation with 3 conical locking screws (CIN-3). The stiffness, cyclic stability, and failure strength of the fixed fracture models were compared after the corresponding experimental tests.

RESULTS

The failure strength of TBW, CIN-1 and CIN-3 were (313.38±27.68) N, (528.56±53.58) N and (871.04±94.95) N. There was a significant difference between them. However, as for dynamic stability and stiffness, CIN-3 was higher and TBW was lower, with no significant differences between the groups.

CONCLUSION

The biomechanical properties of CIN were superior to those of TBW, and CIN was more stable and solid for fixing transverse olecranon fracture, of which CIN-3 was the strongest.

A new all-suture tension band tape fixation technique for simple olecranon fractures versus conventional tension band wire fixation: a comparative biomechanics study

HYPOTHESIS

Simple transverse or short oblique olecranon fractures without articular comminution are classified as Mayo type IIA fractures and are typically treated with a tension band wire construct. Because of the high reoperation rates, frequently because of prominent hardware, all-suture tension band constructs have been introduced. It was the purpose to compare the biomechanical performance of conventional tension band wire fixation with a new all-suture tension band tape fixation for simple olecranon fractures.

METHODS

Mayo type IIA olecranon fractures were created in 20 cadaveric elbows from 10 donors. One elbow of each donor was randomly assigned to the tension band wire technique (group TBW) or tension band tape (Arthrex, 1.3-mm SutureTape) technique (group TBT). Both groups were cyclically loaded with 500 N over 500 cycles, after which a uniaxial displacement was performed to evaluate load to failure. Data were analyzed for gap formation after cyclic loading, construct stiffness, and ultimate load to failure, where failure was defined as fracture gap formation greater than 4.0 mm.

RESULTS

There was no significant difference in gap formation after 500 cycles between the TBW (1.8 mm ± 1.3 mm) and the TBT (1.9 mm ± 1.1 mm) groups (P = .854). The TBT showed a tendency toward greater construct stiffness compared with the TBW construct (mean difference: 142 N/mm; P = .053). Ultimate load to failure was not significantly different comparing both groups (TBW: 1138 N ± 286 N vs. TBT: 1126 N ± 272 N; P = .928). In both groups, all repairs failed because of >4.0-mm gap formation at the fracture site and none because of tension band construct breakage.

CONCLUSIONS

Our study shows that the TBT technique produces equivalent or superior biomechanical performance to the TBW for simple olecranon fractures. The TBT approach reduces the risk of hardware prominence and as a result mitigates against the need for hardware removal. The TBT technique offers a clinically viable alternative to TBW.

Lag screw osteosynthesis of simple olecranon fractures: A biomechanical comparative study

Olecranon fractures are most frequently stabilized by tension band wiring (TBW), which unfortunately leads to relevant implant removal rates due to K-wire migration and soft tissue irritation. As lag screw osteosynthesis (LSO) might be a gentle and effective alternative in simple fracture patterns, the goal of the present study was to biomechanically compare LSO with TBW in simple olecranon fractures at a cadaver model. A simple olecranon fracture (Mayo type IIA) was created in eight pairs of human cadaver elbows, which were pairwise fixed by either TBW or two transcortical 4.0 mm lag screws. Biomechanical testing was conducted as a pulling force, applied to the triceps tendon in a 90° position. First, cyclic loading between 10 and 300 N was performed for 50,000 cycles. Afterward, maximum load was raised by 0.02 N/cycle until construct failure, what was defined as displacement >2 mm. Besides fracture displacement, failure cycle and failure load, the modes of failure were analyzed. Within the first five cycles, there was no significant difference in displacement (median TBW: 0.2 mm; LSO: 0.5 mm; p = 0.091). Both after 2000 (median TBW: 0.2 mm; LSO: 0.6 mm; p = 0.042) and after 20,000 cycles (median TBW: 0.4 mm; LSO: 0.9 mm; p = 0.027), the difference was significant. Failure cycle (median TBW: 72,639 cycles; LSO: 43,429 cycles; p = 0.017) and failure load (median TBW: 702 N; LSO: 303 N; p = 0.025) differed significantly as well. TBW mostly (6/8) failed at the lock of the cerclage wire, whereas most LSO constructs (5/8) failed as a pullout of the proximal fragment. In conclusion, to our biomechanical findings at human cadaver specimens, simple olecranon fractures treated by LSO show higher dislocation rates and lower failure loads compared to conventional TBW and mostly fail by pullout of the proximal fragment.

Cost Assessment of Plating Versus Tension Band Wiring Constructs for Treating Mayo Type 2A Olecranon Fractures

PURPOSE

Tension band wiring (TBW) or plating may be used for fixation with similar clinical outcomes for adults with displaced Mayo 2A olecranon fractures. The primary hypothesis is that total direct costs (TDCs) for surgery are lower for TBW than plating. Our secondary hypothesis is that combined surgical TDCs are lower for TBW even with a 100% rate of subsequent tension band hardware removal and a 0% rate of plate removal.

METHODS

Patients who underwent TBW or plating of an isolated unilateral Mayo 2A olecranon fracture between July 2011 and January 2020 at a single academic medical center were identified. Then, TDC for each surgery on plate fixation, TBW, and hardware removal was obtained and converted to 2020 US dollars using information technology cost tools provided by our institution. Finally, relative TDCs were compared between plate fixation and TBW groups using univariate and multivariable generalized estimating equations with log-link.

RESULTS

Of the 97 included patients, the mean age was 50 ± 21 years, and 48% were female. Tension band wiring and plate fixation were performed on 18% (17/97) and 82% (80/97) of male and female patients, respectively. Demographics were similar between groups, although the finding that plate fixation cost 2.6 times that of TBW within the index surgery was significant in the multivariable model, independent of potential confounders (coefficient 2.55, 95% confidence interval: 2.09-3.10). Additionally, mean TDC remained significantly greater for plate fixation even under the hypothetical situation where 100% TBW were removed, and the plate removal rate was 0% (cost difference 181%).

CONCLUSIONS

Using TBW relative to plate fixation may improve the cost of care for operative Mayo 2A olecranon fractures. Furthermore, this finding was robust to the rate of hardware removal.

TYPE OF STUDY/LEVEL OF EVIDENCE

Economic and Decision Analyses III.

The Effect of Buttress Plating on Biomechanical Stability of Coronal Shear Fractures of the Capitellum: A Cadaveric Study

PURPOSE

The purpose of this study was to compare, using a cadaveric model, the biomechanical properties of headless compression screws (HCSs) and HCSs augmented with a buttress plate (BP) in capitellar fractures.

METHODS

Twenty pairs of fresh-frozen humeri (mean age, 46.3 years; range, 33-58 years) were used. The soft tissue was removed, and a Dubberley type IA capitellar fracture was created. One specimen in each pair was randomly assigned to receive either two 2.5-mm HCSs (HCS group) or two 2.5-mm HCSs augmented with an anterior 2.4-mm BP (HCS + BP group). This resulted in a similar distribution of the left and right humeri between the groups. Cyclic loading was performed, and displacement of the capitellum at 50, 100, 250, 500, 1,000, and 2,000 cycles was assessed using a motion capture system. This was followed by load-to-failure testing, wherein the load at a displacement of 1 and 2 mm was recorded. Failure was defined as 2-mm displacement.

RESULTS

During cyclic loading, there were no significant differences in the displacement between the HCS and HCS + BP groups at any of the assessed cycles. During load-to-failure testing, no significant strength differences were observed in the load at 1-mm displacement between the HCS (mean: 449.8 N, 95% CI: 283.6-616.0) and HCS + BP groups (mean: 606.2 N, 95% CI: 476.4-736.0). However, a significantly smaller load resulted in a 2-mm displacement of the fragment in the HCS group (mean: 668.8 N, 95% CI: 414.3-923.2) compared with the HCS + BP group (mean: 977.5 N, 95% CI: 794.1-1,161.0).

CONCLUSIONS

Anterior, low-profile buttress plating in addition to HCSs results in a significantly higher load to failure compared with HCSs alone in a biomechanical Dubberley type IA capitellar fracture model.

CLINICAL RELEVANCE

The addition of an anterior BP may be considered to improve initial stability in select cases such as osteoporotic patients or when the posterolateral column is frail.

Predicting secondary surgery after operative fixation of olecranon fractures: a model using data from 800 patients

Background

High rates of secondary surgery after fixation of olecranon fractures have been reported. Identification of risk factors can aid surgeons to reduce complications leading to additional surgical procedures.

Methods

Olecranon fractures treated at seven hospitals from 2007 to 2017 were identified, and the radiographs were classified. Isolated, displaced olecranon fractures treated operatively with tension band wiring (TBW) or precontoured plate fixation (PF) were reviewed. Adjusted risk factors for secondary surgery were analyzed, and a multivariable predictive model for secondary surgery was built.

Results

After the initial review of 1259 olecranon fractures, 800 isolated, displaced olecranon fractures met the inclusion and exclusion criteria. The distribution of two-part and multifragmented fractures was equal. TBW was used in 636 patients and PF in 164 patients. Multifragmentation was a significant variable influencing preference for PF. Secondary surgery was performed in 41% patients and symptomatic hardware removal was the most frequent primary indication. In both the TBW and PF group, the rates of major complications leading to secondary surgery were 13% (P = .96). The adjusted risk of secondary surgery was lower with increasing age (odds ratio by 10 years increments, 0.74; 95% confidence interval, 0.68-0.80, P < .01). Compared with PF, TBW with transcortical K-wires (odds ratio, 2.06; 95% confidence interval, 1.36-3.14; P < .01) and TBW with intramedullary K-wires (odds ratio, 4.32; 95% confidence interval, 2.16-8.86, P < .01) had significantly higher adjusted risk of secondary surgery.

Conclusion

Surgeons preferred to use PF in younger patients and multifragmented fractures. Patients should be counseled that secondary surgery is common after surgical fixation of olecranon fractures. Symptomatic hardware removal was the most frequently reported reason for secondary surgery and more frequent after TBW. When using TBW, intramedullary K-wire positioning should be avoided. The rate of major complications leading to secondary surgery was similar in the TBW and PF groups. Overall, the risk of subsequent secondary surgery was higher in younger patients and patients treated with TBW.

Comparison of tension band wiring and plate fixation in Mayo type 2A olecranon fractures

OBJECTIVES

This study aims to compare clinically and functionally patients who had previously undergone tension band wiring (TBW) or plate fixation (PF) procedure due to the diagnosis of Mayo type 2A olecranon fracture in our clinic.

PATIENTS AND METHODS

Data of 92 patients (51 males, 41 females; mean age 42.3±12.6 years; range, 16 to 75 years) operated on for olecranon fractures between January 2014 and December 2018 were recorded retrospectively. Forty-four patients received TBW and 48 patients received PF treatment. Their Disabilities of the Arm, Shoulder, and Hand (DASH) and Mayo scores and elbow range of motion (ROM) measurements were used for clinical and functional evaluations. Data including the time to return to work, revision rate, and follow-up time were also recorded.

RESULTS

The mean follow-up time was 38.2±17.2 months. Patients returned to work in 9.2±4.1 weeks in the TBW group and 7.8±3.6 weeks in the PF group (p=0.279). The revision rate was 14% in the TBW group and 2% in the PF group (p=0.335). The mean DASH score was 10.0±1.8 in the TBW group and 7.7±1.2 in the PF group (p=0.001). The mean Mayo score was 84.0±9.3 in the TBW group and 88.3±9.1 in the PF group (p=0.049). For elbow flexion-extension ROM, 4° of difference was measured in favor of the PF group (p=0.043). Mean Mayo score, mean DASH score, and mean flexion-extension ROM values were statistically significantly different between the two groups.

CONCLUSION

Both surgical techniques are suitable and reliable in the treatment of olecranon fractures. Although TBW treatment is low-cost and simple to apply, its biggest disadvantage is a high rate of secondary surgery for implant removal due to irritation of the skin.