Radial head fractures.

The shape and size of the radial head is highly variable but correlates to the contralateral side. The radial head is a secondary stabilizer to valgus stress and provides lateral stability. The modified Mason-Hotchkiss classification is the most commonly used and describes three types, depending on the number of fragments and their displacement. Type 1 fractures are typically treated conservatively. Surgical reduction and fixation are recommended for type 2 fractures, if there is a mechanical block to motion. This can be done arthroscopically or open. Controversy exists for two-part fractures with >2 mm and <5 mm displacement, without a mechanical bloc as good results have been published with conservative treatment. Type 3 fractures are often treated with radial head replacement. Although radial head resection is also an option as long-term results have been shown to be favourable. Radial head arthroplasty is recommended in type 3 fractures with ligamentous injury or proximal ulna fractures. Failure of primary radial head replacement may be due to several factors. Identification of the cause of failure is essential. Failed radial head arthroplasty can be treated by implant removal alone, interposition arthroplasty, revision radial head replacement either as a single stage or two-stage procedure.

Comparison of interfragmentary compression in conventional and locked plating of proximal unicondylar tibia fractures : A biomechanical cadaver study.

The extent of interfragmentary compression in intra-articular fractures treated with various fixation methods have not yet been reported. Lateral split fractures were created in six pairs of cadaver tibiae treated -using buttress plating with lag screws (group C) or locked buttress plating after clamp compression (group L). Interfragmentary compression and fracture displacement were continuously measured using pressure sensors and a stereoscopic 3-D image correlation system. Significantly larger interfragmentary compression was found initially after clamping the fragment (p < 0.05) in group C (median ±â€ˆSD ; 45.1 ±â€ˆ5.0 N/mm2) compared with group L (33.6 ± 3.4 N/mm2), and a statistical trend towards larger compression was also found after cyclic loading (p = 0.05) in group C (45.3 ±â€ˆ8.6 N/mm2) compared with group L (28.7 ±â€ˆ5.8 N/mm2). These data indicate that conventional plating with lag screws achieves higher interfragmentary compression in this model compared with external clamp compression and locked plating.

Open Reduction and Internal Fixation of Fractures of the Proximal Part of the Humerus.

INTRODUCTION: We describe the surgical technique for open reduction and internal fixation (ORIF) of proximal humeral fractures with a locking plate. STEP 1 PREOPERATIVE PLANNING: To choose the right candidate, obtain a full understanding of the patient's fracture pattern, activity level and demands, and bone quality; be aware of predictors of complications and poor outcomes. STEP 2 PATIENT POSITIONING: Place the patient in the beach-chair position with the arm draped free or in a hydraulic device with good access for the image intensifier. STEP 3 APPROACH: The deltopectoral approach is generally preferred because of the exposure obtained, the possibility of distal extension, and the minimal risk of nerve injury. STEP 4 REDUCTION AND FIXATION OF THE TUBEROSITIES THE KEY TO OBTAINING MARIONETTE-LIKE CONTROL: The control, reduction, and fixation of the tuberosities are crucial to restore the anterior-posterior force couple of the shoulder and must therefore be done properly no matter what the fracture pattern looks like. STEP 5 FRACTURE REDUCTION: After carrying out Steps 1 through 4, perform the reduction techniques for the specific fracture type as described below for types that we think suitable for ORIF with a locking plate. STEP 6 FIXATION IMPLANT-SPECIFIC CONSIDERATIONS: Plate length and positioning, humeral head screw placement, distal locking, confirming the screw tip position with the image intensifier, and securing the tuberosities. STEP 7 TENOTOMY OR TENODESIS OF THE LONG BICEPS TENDON: Perform a biceps tenotomy if the biceps is displaced out of the groove by the fracture pattern or if you have to open the rotator interval. STEP 8 WOUND CLOSURE: Do not close the deltopectoral interval. STEP 9 REHABILITATION: As the failure rate of ORIF of proximal humeral fractures is high, do not force an active rehabilitation protocol. RESULTS: In our analysis of 269 fractures followed for twelve months, we found that the Constant-Murley score (CMS) and Short Form-36 (SF-36) score improved continuously during the first six months postoperatively.IndicationsContraindicationsPitfalls & Challenges.

CT metal artefact reduction for internal fixation of the proximal humerus: value of mono-energetic extrapolation from dual-energy and iterative reconstructions.

AIM: To assess the value of dual-energy computed tomography (DECT) and an iterative frequency split-normalized metal artefact reduction (IFS-MAR) algorithm compared to filtered back projections (FBP) from single-energy CT (SECT) for artefact reduction in internally fixated humeral fractures. MATERIALS AND METHODS: Six internally fixated cadaveric humeri were examined using SECT and DECT. Data were reconstructed using FBP, IFS-MAR, and mono-energetic DECT extrapolations. Image analysis included radiodensity values and qualitative evaluation of artefacts, image quality, and level of confidence for localizing screw tips. RESULTS: Radiodensity values of streak artefacts were significantly different (p < 0.05) between FBP (-104 ± 222) and IFS-MAR (73 ± 122), and between FBP and DECT (32 ± 151), without differences between IFS-MAR and DECT (p < 0.553). Compared to FBP, qualitative artefacts were significantly reduced using IFS-MAR (p < 0.001) and DECT (p < 0.05), without significant differences between IFS-MAR and DECT (p < 0.219). Image quality significantly (p = 0.016) improved for IFS-MAR and DECT compared to FBP, without significant differences between IFS-MAR and DECT (p < 0.553). The level of confidence for screw tip localization was assessed as best for DECT in all cases. CONCLUSION: Both IFS-MAR in SECT and mono-energetic DECT produce improved image quality and a reduction of metal artefacts. Screw tip positions can be most confidently assessed using DECT.

Mid term results of distal femoral fractures treated with a polyaxial locking plate: a multi-center study.

OBJECTIVE: Locking plates have become a standard implant in the treatment of distal femoral fractures. Newer designs allow polyaxial screw placement as well as the ability to lock the lag screws. METHODS: The consecutive multi-centre study cohort consists of all distal femoral fractures treated with the NCB® Distal Femur plate (Zimmer, Warsaw, USA) and a minimum follow-up of twelve months. Fracture classification according the AO/ OTA system and the trauma mechanism radiological evaluation and complications were documented. Clinical evaluation consisted of the Short Form SF12 questionnaire (SF12), the Hospital for Special Surgery Score (HSS) and clinical assessment of range of motion. RESULTS: Twenty-five patients with twenty-six fractures were available for follow-up with a minimum required follow-up of twelve months. 81% of the fractures were intra-articular. 48% of the patients were multi-traumatised, 38% having open fractures. All except two went to union (92%) with the primary procedure. The HSS Score was 79 (32-99) and the SF 12 (physical and mental) 40 (19-57) and 54 (21-66) at follow-up. There were five patients requiring surgical revision (19%). CONCLUSION: These fractures are often combined with concomitant injuries. Using modern locked implants high union rates can be achieved with a good function and patient satisfaction when respecting biologic and biomechanical principles.