Patients with humeral shaft pseudoarthrosis is going to be treated with a standard protocol with a locking compression plate and bone autograft, and other group of patients treated with platelet rich plasma.

Posteriorly all the patients it will evaluated radiographically and with functional scales for a period of one year.

Pseudarthrosis is a condition characterized by the absence of union from 3-4 months of the start of a fracture. It usually has symptoms manifested by pain and loss of function of the affected extremity. In addition to radiographic data with lack of consolidation in the fracture. The surgical indications in patients with pseudoarthrosis data are the presence of pain and the mobility of the fracture taking account the time evolution.

The humeral shaft fracture represent 3% of the general fractures, appearing around 66,000 cases per year in the United States. The conservative treatment with a brace has been used since the 1970's. Mostly of the humeral shaft fractures are managed with this option. Contraindications are those fractures which are bilateral or in polytraumatized patients who do not have the ability to roam.

Surgical treatment seeks to provide a stable fixation providing an early mobilization. The union of these fractures occurs in a period ranging from 12 to 24 weeks. The use of a Locking Compression Plate where there must be at least six cortical fixation on both fragments is actually recommended, besides is necessary applies also bone autograft to promote ossification has osteogenic, osteoinductive, and osteoconductive properties, with an radiographic union between the nineteen weeks.

The platelet-rich plasma (PRP) is obtained from a sample of autologous blood, and after processing it have growth factors that stimulate angiogenesis and cell proliferation. It has been used since 1990 to treat jaw fracture with bone autograft and tendon injury in rotator cuff with a good evolution. It has been bone consolidation from 8 to 24 weeks.

Preparation of platelet-rich plasma A 40-ml volume of whole blood was taken from the basilic or antecubital vein of the upper limb in sterile tubes and vacuum sealed with 3.8% sodium citrate as an anticoagulant. The samples were transported to the Tissue Engineering Laboratory of the Bone and Tissue Bank where they were centrifuged for 10 minutes at 1800 rpm to separate the cellular parts corresponding to the erythrocytes and leukocytes. The upper plasma layer was removed from each of the tubes (taking care not to remove the buffy coat) and collected into a 50-ml sterile conical polypropylene tube for a second centrifugation step for 12 min at 3400 rpm. The plasma supernatant, or platelet poor plasma, was removed, leaving a volume of 3 ml in which the platelets were resuspended. The 3 ml of PRP obtained was transferred to a sterile glass tube and vacuum sealed without anticoagulant. An aliquot of the final PRP was sent to the laboratory to quantify the number of platelets. Manipulation of the samples was performed in a sterile environment within a class II biosafety cabinet. Prior to the administration of PRP to the patient, activation of the platelets was induced by adding 0.45 ml of 10% calcium gluconate and inverting the sample several times to ensure a homogeneous mixture. Then, the activated PRP was aspirated with a 5-ml syringe for application to the patient using the technique described above after asepsis and the application of 2 ml of lidocaine into the application site.

The patient must sign the format of informed consent to the authorization of the surgery and the use of platelet-rich plasma.

After signing informed consent, will divide the patients in two randomized groups to make the comparative and longitudinal study. A control group of patients who will receive treatment with surgery on the basis of open reduction with locking compression plate and autologous bone of iliac crest. The experimental group of patients will receive the above-mentioned treatment more the application of plasma rich platelets at the level of the fracture focus.

After the surgery all the patients will be assessed at outpatient at 10 days for evaluation, pendulum exercises and the first radiographic evaluation. The patient will be attending consultation to continue his post-surgical evolution. During the follow-up visits, the radiographic extent of the bony callus was assessed via anteroposterior and lateral radiograph of the arm as follows grade 0, no identifiable bony callus; grade 1, primary bony callus formation with little or no new periosteal bone; grade 2, new periosteal bone formation on two sides of the humerus,; and grade 3, new periosteal bone formation on three or four sides of the humerus. The follow-up is for one year.

Sample size calculation Using a formula to test hypothesis and two mean difference, with a value of zα of 1.96 with significance level of 95 for two tails, and a value zβ of 0.84 with an output of 80, a sample was obtained of 7 participants per group, whereas an average of 19 weeks for group control with a standard deviation of 3 hoping to reduce up to 4 weeks the start of consolidation with the application of PRP.

Inclusion Criteria:

• evolution of 3 months
• initial orthopedic management
• without mental illness

Exclusion Criteria:

• osteoporosis
• contralateral or ipsilateral fractures
• previous fracture in same place at least 3 month
• hematologic problems
• liver disease
• cardiac, renal or lung disease

1 year