Biomechanical analysis of plating techniques for unstable lateral clavicle fractures with coracoclavicular ligament disruption (Neer type IIB).

BACKGROUND: Neer type IIB lateral clavicle fractures are inherently unstable fractures with associated disruption of the coracoclavicular (CC) ligaments. Because of the high rate of nonunion and malunion, surgical fixation is recommended; however, no consensus has been reached regarding the optimal fixation method. A new plating technique using a superior lateral locking plate with anteroposterior (AP) locking screws, resulting in orthogonal fixation in the lateral fragment, has been designed to enhance stability and reduce implant failure. The purpose of this study was to biomechanically compare 3 different clavicle plating constructs within a fresh frozen human cadaveric shoulder model. METHODS: Twenty-four fresh frozen cadaveric shoulders were randomized into 3 groups (n = 8 specimens): group 1, lateral locking plate only (Medartis Aptus Superior Lateral Plate); group 2, lateral locking plate with CC stabilization (No. 2 FiberWire); and group 3, lateral locking plate with 2 AP locking screws stabilizing the lateral fragment. All specimens were subject to cyclic loading of 70 N for 500 cycles. Data were analyzed for gap formation after cyclic loading, construct stiffness, and ultimate load to failure, defined by a marked decrease in the load displacement curve. RESULTS: After 500 cycles, there was no statistically significant difference between the 3 groups in gap formation (P = .179). No specimen (0/24) failed during cyclic loading. Ultimate load to failure was significantly higher in group 3 compared to group 1 (286 N vs. 167 N; P = .022), but not to group 2 (286 N vs. 246 N; P = .604). There were no statistically significant differences in stiffness (group 1: 504 N/mm; group 2: 564 N/mm; group 3: 512 N/mm; P = .712). Peri-implant fracture was the primary mode of failure for all 3 groups, with group 3 demonstrating the lowest rate of peri-implant fractures (group 1: 6/8; group 2: 7/8; group 3: 4/8; P = .243). CONCLUSION: Biomechanical evaluation of the clavicle plating techniques showed effective fixation across all specimens at 500 cycles. The lateral locking plate with orthogonal AP locking screw fixation in the lateral fragment demonstrated the greatest ultimate failure load, followed by the lateral locking plate with CC stabilization. This new plating technique showed compatible stiffness and gap formation when compared to conventional lateral locking plates as well as plates with CC fixation. The use of orthogonal screw fixation in the distal fragment may negate against the need for CC stabilization in these types of fractures, thus minimizing surgical dissection around the coracoid and potential complications.

Complications following arthroscopic-assisted coracoclavicular stabilization in patients with unstable lateral clavicle fractures.

PURPOSE: Lateral clavicle fractures are unstable and prone to nonunions, which is why they are often treated surgically rather than conservatively. Despite the variety of surgical techniques found in the literature, the best method for treating this rare fracture type has not yet been determined. Our case series aimed to describe a coracoclavicular (CC) reconstruction technique and to assess complications and patient outcomes 1 year postoperatively. METHODS: Nineteen patients who underwent surgery for an unstable lateral clavicle fracture (IIB, IIC, IID) with a suture button device (Dog Bone, Arthrex, Inc., Naples, FL, USA) were available for clinical and radiological follow-up. The assessments included the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment (ASES) score, the Constant Score (CS), the Subjective Shoulder Value (SSV), as well as the ipsilateral and contralateral coracoclavicular distance. RESULTS: The median age was 50 years (IQR 28-59), 13 (68.4%) were male and the delay to surgery was 5 days (IQR 2-9). The median clinical scores were 100 (ASES), 91 (CS), and 95 (SSV). The CC distance improved postoperatively (p = 0.003). However, nonunion occurred in 3 (15.8%) patients, 5 (26.3%) had other complications, and 5 (26.3%) needed revision surgery (4 plate removals and 1 pseudoarthrosis). The overall complication rate was 36.8%. CONCLUSION: Restoring the CC ligaments alone could not reliably achieve fracture stability, with more than one-third of cases in this series experiencing major complications. Given the high revision and nonunion rates, we do not recommend this type of surgical technique.

Operative management of lateral third clavicle fractures: a comparison of internal fixation methods.

PURPOSE: Clavicle fractures in the lateral third are associated with more complications. Various methods of internal fixation exist; however, there is no consensus which should be employed. The purpose of this study was to evaluate the outcomes of these various methods in our regional trauma unit. METHODS: We performed a retrospective review of patients who underwent internal fixation of a lateral clavicle fracture in our unit between 1 August 2014 and 31 July 2019. Demographic and outcome data were extracted from electronic care records and imaging systems. RESULTS: In total, 44 patients were included, with the following demographics: mean age 26 years, 63.6% male, 65.9% high-energy injury, 68.2% Neer II fracture. The following operations were performed: hook plate fixation (HPF) = 10, locking plate fixation (LPF) = 16, coracoclavicular ligament reconstruction (CCLR) = 12, and LPF + CCLR = 6. Patients having LPF had a significantly larger post-operative coracoclavicular distance (7.6 mm vs 13.5 mm, p < 0.01), and trends towards a lesser decrease in CCD (9.9 mm vs 12.6 mm, p = 0.37) and incomplete ACJ reduction (50.0% vs 89.3%, p = 0.11). There was a significantly higher re-operation rate after HPF (100% vs 23.5%, p < 0.01). There were no differences in time to union or duration of follow-up. CONCLUSION: In our unit there is no clearly favoured method of internal fixation of lateral clavicle fractures. When LPF is used, there should be consideration of concomitant CCLR. The high rate of re-operation after HPF is concordant with previous research.

Additional coracoclavicular augmentation reduces revision rates in the treatment of lateral clavicle fractures as compared to angle-stable plate osteosynthesis alone.

INTRODUCTION: There is no uniform approach to the management of lateral clavicle fractures. Recent studies have investigated additive coracoclavicular (CC) augmentation as a treatment option; however, it is unclear whether it is superior to conventional locking plate osteosynthesis. METHODS: We carried out a retrospective analysis of 40 patients with lateral clavicle fracture (Neer type IIb) who were treated between 2014 and 2017 with either a hybrid locking plate osteosynthesis/additive arthroscopy-assisted CC augmentation (HP) procedure or a locking plate osteosynthesis only (PO) approach to determine which strategy was more effective. At follow-up, subjective shoulder value, age- and sex-adjusted Constant-Murley score, Taft (TF) score, American Shoulder and Elbow score, Nottingham clavicle score, and Visual Analogue Scale score were compared between patient groups. A radiologic evaluation was also conducted. RESULTS: A total of 14/17 patients (83%; 9 male/5 female, mean age: 43 ± 15 years) were followed up in the PO group. The mean follow-up time was 29 ± 12.4 months. In the HP group, 17/23 patients (74%; 9 male/8 female, mean age: 43 ± 17 years) were followed up, with a mean follow-up time of 18 ± 7.1 months. There were no significant differences in clinical parameters between the HP and PO groups; notably, the shoulder girdle-specific TF score was comparable in the 2 groups (HP: 11.3 ± 1.1 points and PO: 10.9 ± 0.9 points). In the HP group, additional pathologies were identified and arthroscopically treated in 35% of cases. Radiologic examination revealed a significant difference between pre- and postoperative CC distance in the HP group (P = 0.001). CONCLUSION: Additive CC augmentation in combination with locking plate osteosynthesis seems to improve the vertical stability and reduces the revision rate in patients with a lateral clavicle fracture. Furthermore, an arthroscopy-assisted procedure allows for an intraoperative detection and single-step treatment of accompanying intraarticular pathologies.

Surgical treatment of Neer type II and type V lateral clavicular fractures: comparison of hook plate versus superior plate with lateral extension: a retrospective cohort study.

PURPOSE: Different fixation methods are used for treatment of unstable lateral clavicle fractures (LCF). Definitive consensus and guidelines for the surgical fixation of LCF have not been established. The aim of this study was to compare patient-reported functional outcome after open reduction and internal fixation with the clavicle hook plate (CHP) and the superior clavicle plate with lateral extension (SCPLE). METHODS: A dual-center retrospective cohort study was performed. All patients operatively treated for unstable Neer type II and type V LCF between 2011 and 2016, with the CHP (n = 23) or SCPLE (n = 53), were eligible for inclusion. The primary outcome was the QuickDASH score. Secondary outcomes were the numerical rating scale (NRS) pain score, complications, and implant removal. RESULTS: A total of 67 patients (88%) were available for the final follow-up. There was a significant difference in bicortical lateral fragment size, 15 mm (± 4, range 6-21) in the CPH group compared to 20 mm (± 8, range 8-43) in the SCPLE group (p ≤ 0.001). There was no significant difference in median QuickDASH score (CHP; 0.00 [IQR 0.0-0.0], SCPLE; 0.00 [IQR 0.0-4.5]; p = 0.073) or other functional outcome scores (NRS at rest; p = 0.373, NRS during activity; p = 0.559). There was no significant difference in median QuickDASH score or other functional outcome scores between Neer type II and type V fractures. There was no significant difference in complication rate, CHP 11% and SCPLE 8% (relative risk 1.26; [95% CI 0.25-6.33; p = 0.777]). The implant removal rate was 100% in the CHP group compared to 42% in the SCPLE group (relative risk 2.40; [95% CI 1.72-3.35; p ≤ 0.001]). CONCLUSION: Both the CHP and SCPLE are effective fixation methods for the treatment of unstable LCF, resulting in excellent patient-reported functional outcome and similar complication rates. SCPLE fixation is an effective fixation method for the treatment of both Neer type II and type V LCF. The SCPLE has a lower implant removal rate. Therefore, if technically feasible, we recommend SCPLE fixation for the treatment of unstable LCF.

Lateral clavicle fracture with coracoclavicular ligament injury: a biomechanical study of 4 different repair techniques.

PURPOSE: To investigate the biomechanical performance of four different methods used for coracoclavicular (CC) ligament reconstruction in a lateral clavicle fracture repair. METHODS: Native displacement, translation, and rotation at the acromioclavicular joint of 24 fresh-frozen cadaveric shoulders were tested. A reproducible fracture in the lateral third of the clavicle was created by dissecting both CC ligaments. Each specimen was then repaired with plate fixation of the fracture and the following CC repair technique: (1) Cortical button. (2) Suture anchor and plate button. (3) Suture anchor no plate button, and (4) Suture around coracoid. All reconstructed specimens were then re-tested for displacement, translation, and load to failure, and compared to their native results. Groups 1 and 3 were investigated for rotational load. RESULTS: There was no difference in load to failure between the repaired groups (p: ns). Group 1 showed less superior and anterior translations (p < 0.05). Group 2 showed significantly less superior translation (p = 0.003), but no significance with anterior and posterior translations to the native joint. Group 3 showed less superior and posterior translations (p = 0.005 and p = 0.039). Anterior and posterior translations were increased in group 4 (p < 0.05). CONCLUSION: The biomechanical analyses did not show any significance in load to failure or displacement after cyclic loading among the study groups. All repairs were effective in preventing superior translation. Groups 1 and 2 demonstrated increased horizontal stability compared to the native state. All 4 methods are clinically viable options for CC ligament repair.

Concomitant intra-articular glenohumeral injuries in displaced fractures of the lateral clavicle.

PURPOSE: To detect concomitant intra-articular glenohumeral injuries, in acute displaced fractures of the lateral clavicle, initially missed due to unfeasible clinical evaluation of the acutely injured shoulder. METHODS: All patients suffering from an acute displaced lateral clavicle fracture with indication to surgical treatment underwent diagnostic shoulder arthroscopy prior to open reduction and internal fixation. In case of therapy-relevant intra-articular glenohumeral injuries, subsequent surgical treatment was performed. RESULTS: Intra-articular injuries were found in 13 of 28 patients (46.4 %) with initially suspected isolated lateral clavicle fracture. Additional surgical treatment was performed in 8 of 28 cases (28.6 %). Superior labral anterior-posterior (SLAP) lesions were observed in 4 of 28 patients (14.3 %; SLAP II a: 1; II b: 1; III: 1; and IV: 1). Lesions of the pulley system were found in 3 of 28 patients (10.7 %; Habermeyer III°). One partial articular supraspinatus tendon avulsion lesion (3.6 %) and one lesion of the subscapularis tendon (3.6 %; Fox and Romeo II°) were observed. CONCLUSIONS: Traumatic concomitant glenohumeral injuries in lateral clavicle fractures seem to be more frequent than expected in general. Subsequent surgical treatment of these formerly missed but therapy-relevant injuries may increase functional outcome and reduce complication rate. LEVEL OF EVIDENCE: IV.

Long-term results following polydioxanone sling fixation technique in unstable lateral clavicle fracture.

Neer type II (Edinburgh type 3B) fractures of the lateral clavicle are unstable fractures. The optimal management of these fractures remains controversial with many surgical techniques described in the literature. Our study reports the long-term results of a modified suture (1.5-mm polydioxanone cord) and sling technique for these fractures to avoid complications associated with current techniques in the literature. Over a 5-year period, 23 patients who were (12 males, 11 females; 14 left, 9 right) with a mean age of 42 years were treated with this technique. At last follow-up, the mean Oxford score was 45.1 (range 36-48); the mean SPADI score was 7.4 (range 0-32.3); and the mean Constant score was 91.5 (range 71-100). There were one non-union and no malunion. All patients in our series, except one, returned to their pre-injury activity level. This modified suture fixation technique is safe, technically simple to perform and cheap. It achieves excellent rates of fracture union without the complications associated with other fixation methods in the literature.

Arthroscopically Assisted Coracoclavicular (CC) Stabilization Using a Suture Button Device for Lateral Clavicle Fractures with CC Ligament Injury.

Background: Lateral clavicle fractures represent approximately 10-15% of all clavicle fractures. However, controversy exists regarding the optimal surgical treatment because of instability associated with the coracoclavicular (CC) ligament injury and a small lateral fragment. The purpose of this study was to evaluate the radiological and clinical outcomes of arthroscopically assisted CC stabilization using a suture button device for lateral clavicle fractures accompanied by CC ligament injury. Methods: A retrospective observational study involved six patients with modified Neer type IIB fractures, which were treated with the technique and followed for 12 months. Postoperative range of motion (ROM) and X-rays were evaluated every 3 months. Shoulder functional scores (University of California Los Angeles score, Japanese Orthopedics Association score) and visual analog scale (VAS) scores for pain (at rest, at night, and during motion) and for satisfaction were analyzed 12 months after surgery. Results: Early phase ROM recovery and excellent outcomes were achieved. All patients achieved bone union. Slight superior clavicle displacement and bone hole dilation occurred with no critical complications. Conclusions: Arthroscopically assisted CC stabilization with a suture button device for unstable lateral clavicle fractures can produce satisfactory radiological and clinical results.

[Combined intrapulmonary/intramediastinal K-wire position after K-wire osteosynthesis of the clavicle : A case report]. / Kombinierte intrapulmonale/intramediastinale K-Draht-Lage nach K-Draht-Osteosynthese an der Clavicula : Ein Case Report.

BACKGROUND: Lateral clavicle fractures can be treated both conservatively and surgically depending on the fracture classification. Different surgical techniques have been described for the operative treatment. The selection of the appropriate technique is decisive for the functional outcome and healing process without complications. CASE: We report on a patient with a secondary dislocation of two Kirschner wires after Kirschner wire osteosynthesis. The secondary dislocation caused one of the wires to migrate into the mediastinum and pulmonary tissue, directly under the aortic arch. To prevent further migration with potential damage to surrounding structures, a uniportal video-assisted thoracoscopy was performed to retrieve the wire. CONCLUSION: The treatment of lateral clavicle fractures should be performed with bent Kirschner wires as they can otherwise lead to severe complications including the occurrence of pseudarthrosis or secondary migration of the material. Safe and stable surgical techniques (plate osteosynthesis, hybrid treatment) should be preferred if they are available.

Comparison of Interobserver Agreement of Four Classification Systems for Lateral Clavicle Fractures between Two Groups of Surgeons: A Multicenter Study.

OBJECTIVE: Distal clavicle fracture classification directly affects the treatment decisions. It is unclear whether the classification systems implemented differ depending on surgeons' backgrounds. This study aimed to compare the interobserver agreement of four classification systems used for lateral clavicle fractures by shoulder specialists and general trauma surgeons. METHODS: Radiographs of 20 lateral clavicle fractures representing a full spectrum of adult fracture patterns were analyzed by eight experienced shoulder specialists and eight general trauma surgeons from 10 different hospitals. All cases were graded according to the Orthopedic Trauma Association (OTA), Neer, Jäger/Breitner, and Gongji classification systems. To measure observer agreement, Fleiss' kappa coefficient (κ) was applied and assessed. RESULTS: When only X-ray films were presented, both groups achieved fair agreement. However, when the 3D-CT scan images were provided, improved interobserver agreement was found in the specialist group when the OTA, Jäger/Breitner, and Gongji classification systems were used. In the generalist groups, improved agreement was found when using the Gongji classification system. In terms of interobserver reliability, the OTA, Neer, and Jäger/Breitner classification systems showed better agreement among shoulder specialists, while a slightly lower level of agreement was found using the Gongji classification system. For the OTA classification system, interobserver agreement had a mean kappa value of 0.418, ranging from 0.446 (specialist group) to 0.402 (generalist group). For the Neer classification system, interobserver agreement had a mean kappa value of 0.368, ranging from 0.402 (specialist group) to 0.390 (generalist group). For the Jäger/Breitner classification system, the inter-observer agreement had a mean kappa value of 0.380, ranging from 0.413 (specialist group) to 0.404 (generalist group). For the Gongji classification system, interobserver agreement had a mean kappa value of 0.455, ranging from 0.480 (specialist group) to 0.485 (generalist group). CONCLUSION: Generally speaking, 3D-CT scans provide a richer experience that can lead to better results in most classification systems of lateral clavicle fractures, highlighting the value of digitization and specialization in diagnosis and treatment. Competitive interobserver agreement was exhibited in the generalist group using the Gongji classification system, suggesting that the Gongji classification is suitable for general trauma surgeons who are not highly experienced in the shoulder field.

The use of Tightrope device as the sole method of fixation in treating lateral end clavicle fractures.

BACKGROUND: Lateral end clavicle fractures can be challenging due to the small and often comminuted lateral fragment, problems with union and stability and implant morbidity. We retrospectively reviewed outcomes of Tightrope device in isolation to treat lateral end clavicle fractures. METHODS: Subjective and objective measures were assessed for 29 patients. The subjective comprised of functional clinical scores: Oxford shoulder score and EuroQoL5D. The objective measures were maintenance of fracture reduction, bone healing and complications. RESULTS: Median age was 36 years and 72% of cases were male patients. Average clinical follow up time was 21 months. Evaluation of latest radiographs showed that all reductions were maintained post-operatively. Twenty-two fractures had united and one patient had established non-union. Functional outcomes showed predominantly good results with Oxford shoulder score average of 41, EuroQoL5D index score of 0.78 and EuroQol Visual Analogue Scale 76. The overall post-operative complication rate was 10%; only one case requiring a secondary procedure. DISCUSSION: In our series, using the Tightrope as the sole device to treat displaced lateral end of clavicle fractures resulted in good radiological and functional outcomes, with minimal complications requiring secondary procedures. We believe the Tightrope device is a good method of fixing these challenging fractures and advocate its use.

Posterior Displacement and Angulation of Displaced Lateral Clavicle Fractures: A 3-Dimensional Analysis.

BACKGROUND: The management of lateral clavicle fractures is often challenging because of difficulties in identifying displacement patterns that indicate an unstable fracture. HYPOTHESIS: The aim of this study was to evaluate displacement patterns through analysis using 3-dimensional (3D) rendering software for displaced lateral clavicle fractures. We hypothesized that most displaced lateral clavicle fractures would have posterior displacement and angulation as well as superior displacement of the medial fragment. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Radiographs of 37 displaced lateral clavicle fractures were imported into the 3D rendering software to reconstruct the fracture model. For the computational simulation of fracture reduction, the medial fragment was manipulated and returned into place using the software's moving tools. Two corresponding points were marked between the medial and lateral fragments to measure 3D spatial location in the x-axis (shortening), y-axis (horizontal displacement), and z-axis (vertical displacement). The displacement angle on the cranial view was also measured based on the medial end of the clavicle. RESULTS: There were 32 cases (86.5%) of superior displacement of the medial fragment (mean, 5.8 mm; range, -6.5 to 19.0 mm), 35 cases (94.6%) of posterior displacement of the medial fracture fragment (mean, 8.8 mm; range, -3.2 to 18.3 mm), and 23 cases (62.2%) of distraction of the fracture site (mean, 2.1 mm; range, -9.2 to 12.2 mm). All 37 patients revealed posterior angulation of the fracture site (mean, 8.9°; range, 2.2°-39.4°). CONCLUSION: Most displaced lateral clavicle fractures have posterior displacement and angulation as well as superior displacement of the medial fragment. Our results revealed that 3D evaluation of lateral clavicle fracture displacement patterns is useful for assessing fracture stability and making treatment decisions.

Inter- and intraobserver agreement of three classification systems for lateral clavicle fractures - reliability comparison between two specialist groups.

BACKGROUND: Although of great value in the management of lateral clavicle fractures, substantial variation in their classification exists. We performed a retrospective study to address the inter- and intraobserver reliability of three different classification systems for lateral clavicle fractures. METHODS: Radiographs of 20 lateral clavicle fractures that represented a full spectrum of adult fracture patterns were graded by five experienced radiologists and five experienced trauma surgeons according to the Orthopaedic Trauma Association (OTA), the Neer, and the Jäger/Breitner classification systems. This evaluation was performed at two different time points separated by 3 months. To measure the observer agreement, the Fleiss kappa coefficient (κ) was applied and assessed according to the grading of Landis and Koch. RESULTS: The overall interobserver reliability showed a fair agreement in all three classification systems. For the OTA classification system, the interobserver agreement showed a mean kappa value of 0.338 ranging from 0.350 (radiologists) to 0.374 (trauma surgeons). Kappa values of the interobserver agreement for the Neer classification system ranged from 0.238 (trauma surgeons) to 0.276 (radiologists) with a mean κ of 0.278. The Jäger/Breitner classification system demonstrated a mean kappa value of 0.330 ranging from 0.306 (trauma surgeons) to 0.382 (radiologists).The overall intraobserver reliability was moderate for the OTA and the Jäger/Breitner classification systems, while the overall intraobserver reliability for the Neer classification system was fair.The kappa values of the intraobserver agreements showed, in all classification systems, a wide range with the OTA classification system ranging from 0.086 to 0.634, the Neer classification system ranging from 0.137 to 0.448, and a range from 0.154 to 0.625 of the Jäger/Breitner classification system. CONCLUSIONS: The low inter- and intraobserver agreement levels exhibited in all three classification systems by both specialist groups suggest that the tested lateral clavicle fracture classification systems are unreliable and, therefore, of limited value. We should recognize there is considerable inconsistency in how physicians classify lateral clavicle fractures and therefore any conclusions based on these classifications should be recognized as being somewhat subjective.

Lateral Clavicle Fractures with Coracoclavicular Ligament Disruption (Neer's Type IIB): Review of Literature and a New Technique for All-Suture Fixation.

BACKGROUND: All-suture fixation for the treatment of Neer's Type IIB lateral clavicle fractures by coracoclavicular (CC) ligament reconstruction has become popular in the past decade. Results of modified under-coracoid-around-clavicle (UCAC) technique are reported in this paper. METHODOLOGY AND RESULTS: Nineteen consecutive patients with minimum 6-month followup (FU) were identified. Average FU was 23 months (6-47 m), mean age was 38 years (16-81), and male-to-female ratio was 2:1. The time to surgery varied from 4 days to 12 weeks. Two patients had primary lateral end excision; of the rest, all but one healed fully. Average time to regain full range of motion was 4 weeks; postoperative Oxford Shoulder Score at 6 months was 43. All the patients returned to their previous occupation. One patient showed mild osteolysis on the last X-rays. There were no cases with infections or stiffness. DISCUSSION: CC ligament reconstruction converts the unstable Type IIB fracture into stable Type I; therefore, it is unnecessary to fix the distal fragment separately. Standard plating procedures are technically challenging due to small lateral fragment and frequently require a second operation for implant removal. The cost of commercially available implants vary from ≤750 to ≤1450. This technique is quick, easy to perform, provides good primary stability, and comparable union rates with other techniques at an implant cost of <£120. CONCLUSION: This is a reproducible and efficient technique that provides comparable results with other established procedures at a fraction of the cost of the next cheapest implant. It is recommended for the treatment of displaced Type II clavicle fractures. LEVEL OF EVIDENCE: Level IV.

A biomechanical comparison of two plating techniques in lateral clavicle fractures.

BACKGROUND: Neer Type IIb lateral clavicle fractures typically lead to dislocation of the medial fragment. Therefore, most surgeons recommend surgical treatment for such a fracture pattern. The use of a locking compression plate with a lateral extension has produced satisfactory results in various studies over recent years. Double-plate fixation is a common technique in the treatment of complex distal radius fractures. The authors use this technique as a routine procedure in the treatment of Neer type IIb fractures. In this biomechanical testing study, the mechanical properties of the two techniques were compared. METHODS: On 20 clavicles from fresh frozen cadavers a Neer Type IIb fracture-like osteotomy was performed. A cyclic loading test followed by a load-to-failure test was carried out. Parameters for statistical evaluation were the stiffness at cycles 1, 100 and 17,500 as well as the ultimate tensile load and the deformation at the point of failure. FINDINGS: All specimens withstood the cyclic loading test without any noticeable damage. At cycles 100 and 17,500, the double-plate technique was less stiff. Failure loads were not significantly different from each other, but deformation at the point of failure was significantly greater for the double-plate technique. INTERPRETATION: Both techniques provided sufficient fixation to the fracture site to endure the cyclic loading test, which is supposed to simulate an incident-free week postoperatively. In summary, the double-plate technique offers biomechanically a feasible alternative to the single-plate technique in lateral clavicle fractures of Neer Type IIb.

Comparison of 2 plating techniques for lateral clavicle fractures, using a new standardized biomechanical testing setup.

BACKGROUND: Conservative treatment of lateral clavicle fractures (Neer type II) often ends with unsatisfactory results for patients. Operative treatment is thus gaining acceptance. A retrospective study found success using a double plate technique for these injuries. For the current study, a standardized testing setup was developed to compare the mechanical properties of single versus double plate technique for lateral clavicle fractures. METHODS: Six synthetic bones were tested for each technique. Neer type IIB fractures were created using computer-aided design (CAD). Fatigue testing was carried out with a cantilever bending test. Parameters measured were cycles undergone, failure load and stiffness at the point of failure. RESULTS: The standardized testing setup was able to provide reproducible failures. The double plate technique lasted about 16,000 more cycles and withstood an additional 22.4 N on average. CONCLUSIONS: The new modified standardized testing setup produced reproducible fixation failures for both clavicle fracture fixation techniques. The double plate technique seems to be mechanically superior to the single plate technique.

Combination of a floating clavicle and a posterior shoulder dislocation: An "Unhappy Triad" of the shoulder girdle.

We present a case of a 31-year-old man who suffered from a floating clavicle in combination with a reverse Hill-Sachs lesion of his right shoulder girdle after a bicycle accident. Operative treatment was performed using minimal-invasive and arthroscopically assisted techniques. We strongly recommend an early CT scan with later 3-dimensional reconstruction to detect and fully understand these complex injuries.

Locking plates for displaced fractures of the lateral end of clavicle: Potential pitfalls.

Roughly a quarter of all clavicle fractures occur at the lateral end. Displaced fractures of the lateral clavicle have a higher rate of nonunion. The management of fractures of the lateral clavicle remains controversial. Open reduction internal fixation with a superiorly placed locking plate is a recently developed technique. However, there are no randomized controlled trials to evaluate the efficacy of this procedure. We present a series of four cases which highlight the technical drawbacks with this method of fixation for lateral clavicle fractures. Two cases show that failure of the plate to negate the displacing forces at the fracture site can lead to plate pullout. Two cases illustrate an unusual complication of an iatrogenic injury to the acromioclavicular joint capsule which led to joint instability and dislocation. We advise caution in using this method of fixation. Recent studies have described the success of lateral clavicle locking plate fixation augmented with a coracoclavicular sling. This augmentation accounts for the displacing forces at the fracture site. We would recommend that when performing lateral clavicle locking plate fixation, it should be reinforced with a coracoclavicular sling to prevent plate failure by lateral screw pullout.