ASSESSMENT OF FUNCTIONAL OUTCOME OF HUMERAL DIAPHYSEAL FRACTURES TREATED WITH DYNAMIC COMPRESSION PLATE AT NATIONAL MEDICAL COLLEGE AND TEACHING HOSPITAL, BIRGUNJ, NEPAL

Introduction: Fractures of the humeral shaft account for roughly 3-5% of all fractures and result from direct and indirect trauma. Common mechanism for this fractures include fall on the motor vehicle accidents, fall on out stretched hand and direct loads to the arm. The shaft of humerus fracture is managed largely conservatively, but with the advent of new surgical techniques and implant options, less tolerance for acceptable deformity and functional deficits, more time consuming with conservative management, many surgeon are increasingly likely to consider surgical management. The aim of our study is to assess the functional outcome of dynamic compression plate in shaft of humerus fracture. Materials and Methods: This is a prospective observational study conducted in department of orthopedic surgery, NMCTH, Birgunj among 45 patients from 17 years and above presenting with shaft of humerus fracture. The fracture was classified according to AO classification. The patients were treated with open reduction and internal fixation with dynamic compression plate and followed up at 2 weeks, 6 weeks, 12 weeks and 24 weeks till the radiological union was achieved. American shoulder and elbow surgeon’s scoring system was used to assess the final outcome of the study. Results: 45 patients meeting inclusion criteria were included in the study, 3 patients lost follow up hence removed from study. Out of 42 patients, mean age of the patient was 31.95 years. Most of them 27(64.3%) were male. Predominant fracture was on left side 73.8% (31 patients). The study finding showed that 31(73.8%) sustained injury due to road traffic accidents. Majority of the fractures 32(76.20%) were in middle 1/3rd. Most of the patient had A3 type of fracture according to AO classification. The mean post-operative immobilization was 15years .Forty one (97.61%) fracture united with one (2.39%) fracture going into non-union with mean time of 16.04 weeks. Thirty-seven (88.10%) patients has excellent range of motion of elbow and shoulder while 3(7.10%) had good and 2(4.8%) patient had poor functional outcome. The average ASES score obtained at 24 weeks was 47.07. Conclusion: From our study, it is concluded that open reduction and internal fixation with DCP in shaft of humerus fracture provides excellent functional outcome


INTRODUCTION
Fractures of the humeral diaphysis constitute approximately 3% of all fractures and 20% of fractures of the humerus. 1 Humeral shaft fractures are a relatively common fractures with an incidence of 13 per 100000 per year. 2 The predominant causes of humeral diaphyseal fractures include simple falls or rotational injuries in the older population and higher energy mechanisms in the younger patients including road traffic accidents, physical assaults, fall from height and throwing injuries. 3nctional bracing, initially popularized by Sarmiento in 1977, has essentially replaced all other conservative methods and has become the "gold standard" for nonoperative managements. 4,5However, conservative methods of treatment in patients with multiple injuries led to a high incidence of malunion and nonunion. 6th recent advancement in fracture fixation techniques and biomaterials, success of improved Surgical treatment and low complication rate, surgical management of humeral fracture has become a potential option which is under acceptance as a first choice of management. 7esides, Operative treatment is indicated in specific circumstances including open fractures, associated neurovascular injury, proximal and distal articular extension, patients with multiple injuries or polytrauma, floating elbow, progressive radial nerve deficits, significant soft tissue injury (unable to brace), pathologic fractures and failed non-operative management, Surgical stabilization of humeral shaft fracture has undergone revolutionary changes and treatment modalities adopted are compression plate fixation, intramedullary fixation and external fixation. 8,9The goal of operative treatment of humeral shaft fractures is to reestablish length, alignment, and rotation with fixation that allows early motion and early weight bearing on the fractured extremity. 7e most important advantage of compression plate fixation is that it provides a very stable fixation maintaining rotation, length and angulation of the fracture without injuring the rotator cuff and the elbow joint.It makes early mobilization of limb possible and a pain free extremity with reliable fracture union and excellent function. 10e current study has been carried out to evaluate the functional and radiological outcome of shaft of humerus treated by open reduction and internal fixation with dynamic compression plate.

MATERIALS AND METHODS
With the ethical clearance from the Institutional Review Committee of National Medical College and after obtaining the informed consent of the patient, prospective observational study was conducted.This is a prospective observational study conducted in department of orthopedic surgery, NMCTH, Birgunj among 45 patients from 17 years and above presenting with shaft of humerus fracture.The fracture was classified according to AO classification.The patients were treated with open reduction and internal fixation with dynamic compression plate and followed up at 2 weeks, 6 weeks, 12 weeks and 24 weeks till the radiological union was achieved.American shoulder and elbow surgeon's scoring system was used to assess the final outcome of the study.

Operational method:
All cases of shaft of humerus fracture meeting inclusion criteria were included.The required information was recorded and proforma was prepared.Radiographs were taken in anterior-posterior view and lateral view and diagnosis were established by clinical and radiological means.'U' slab was applied for immobilization prior to surgery.All patients were taken for elective surgery as soon as a patient is fit for surgery.All patients were operated using a standard prescribed surgical technique by the experienced surgeon.Patient's attendants were explained about the nature of injury and its possible complications and the need for surgery.Written and informed consent were taken from the patients and attendants.Preoperative intravenous 2 nd generation antibiotics (cefuroxime 1.5gm) was given and continued postoperatively.
All patients were operated under general anesthesia.Patient was positioned supine with arm on the arm board.Under all aseptic precautions, painting and draping of the affected part was done.Antero-lateral approach (Henry's approach) was used in all cases.Skin incision was made in the line starting proximally along the anterior margin of deltoid, 5 cm below the acromian process which was curved as it run distally, parallel to the lateral border of the biceps and ending just proximal to the origin of brachioradialis muscle, 7.5 cm above the elbow joint.Superficial and deep fascia were divided in line with the incision and cephalic vein protected and retracted medially.Distal to the insertion of the deltoid, brachialis was split longitudinally at the junction of medial two third and lateral one-third.The humerus was exposed subperiosteally.The distal end of this approach was extended to the groove between the biceps and brachioradialis to end in the antecubital fossa when required.Then, the fractures end were exposed, reduced with reduction forceps, and fixed with a narrow 4.5mm Dynamic compression plate (DCP), engaging a minimum of six cortices with screw fixation in each fragment.None of the cases required primary bone grafting.Wound was closed in layers under negative suction drain.
Post operatively Limb elevation and active finger movements were advised.Intravenous antibiotics was given for three days post operatively and then switched over to oral antibiotics .Suction drain was removed after 24 hours.Check X-rays were taken post operatively both Anteroposterior and lateral view.If uneventful, patients were discharged on the fifth post-operative day after proper dressing.

RESULTS
Total of 45 patients with shaft of humerus fracture aged more than 17 years and was admitted in National Medical College, Birgunj in Orthopedics department from September 2018 to August 2019 were included in this study.These patients were followed up for 6 months post-surgery, 3 patients didn't came for follow-up in subsequent visit so was excluded from this study result.
Out of 42 patients, majority of patients was due to RTA, i.e 31 patient (73.8%), which was more common in 26-35 years age group.Most of the patients, 27 (64.3%)were males and only 15 (35.7%) were females.
There was significance difference in the involvement of the sides in this study.The left side was affected more commonly, in 31 (73.8%)patients, whereas right side was affected in 11 (26.2%)patients.

Figure 1: Gender Distribution of patients
In this study, 7 patients had associated injuries, which comprise of 16.7% of the total sample.Fractures were classified according to AO classification system.Most of the fractures were 12 A3 (45.2%) followed by 12 B2 (19%).The mean duration of hospital stay was 15.28 days.There was however a big variation.It ranged from 6-23 days.
In this study, forty one (97.61%)fracture united with one (2.39%)fracture going into non-union.Non-union was due to infection.Twenty eight fracture united within 12 weeks i.e, 66.66%, while 13 (30.96%)fractures were united within 24 weeks.The average fracture union time was 16.04±5.80weeks.The American shoulder and elbow surgeons (ASES) shoulder score is for 13 activities of daily living requiring full shoulder and elbow movement.The maximum possible score is 52 points.The average ASES score obtained at 24 weeks was 47.07 ± 3.21.It ranged from 38-52.(Median: 47.0)The aim of treatment in these fractures is to achieve length, proper alignment and to maintain favorable environment for bone and soft tissue healing.
In our study, the mean age of the patient was 31.95 years with the maximum number patients in 2 nd and 3 rd decades.Vander Griend et al,in their study suggested mean age of the patient to be 36 years.(5)Tingstad et al, in their study suggested mean age of the patient to be 32.8 years.(11) In most of the studies done by the several author, the mean age of the patient was in between 3 rd to 5 th decades of life, which is similar to our study.
The Sex distribution in our study revealed 64.3% male and 35.7% female.In a study performed by Changulani et al, they found 79% male and 21% female.(12) Another study performed by Haveri et al,found 74% male and 26% female.Most of the studies found Male preponderance compared to female which is similar to our study. 13 our study out of 42 cases of humeral diaphyseal fractures, 31 (73.8%)cases were involved in RTA and 8 (19.06%) had fall from height and 3 (7.14%)cases of humeral shaft fracture was from physical assault due to direct trauma to arm.vander Griend et al, and Haveri et al, also found RTA to be the commonest cause of humerus shaft fractures. 5,13The least common was physical assault.
In  5,13,14 The higher percentage of stiffness in this study emphasizes on patient education and physiotherapy during postoperative management.

CONCLUSION
At the end of the study we came to the conclusion that dynamic compression plating of the humerus produces excellent results in case of fracture shaft of humerus.It is a demanding procedure, proper preoperative planning, cautious soft tissue handling, strict asepsis, proper postoperative rehabilitation and patient education are more important to obtain good results.It provides adequate stabilization of fracture and provide good fixation, if proper preoperative planning, good reduction and surgical technique are followed.Early post-operative mobilization following rigid fixation of the fracture of humerus, with DCP lowers the incidence of stiffness.
Fixation by IMIL may be indicated for specific situations, but is technically more demanding and has a higher rate of complications.Thus, dynamic compression plating remains the management of choice for the fractures of shaft of humerus.

Figure 2 :
Figure 2: Distribution of patient with associated injury Thirty seven (88.1%) of the cases had closed fractures, remaining 11.95% had open fractures.

Table 6 : Distribution of functional Outcome Results (Rommen et al. grading) Freq Percent
12r study non dominant arm were involved and 31 (73.8%) were on left side in right handed patient and 11 (26.2%) on right side.Study done by Heim et al,also found majority of fracture on left side, 14 while Hee et al, showed nearly equal proportions of fractures occurring on both right and left side.6ThemedianASESscoreobtainedwas47 in this study which is similar to the average ASES score of 48,48,45,45 obtained by McCormack et al.17Haveri et al13Putti et al15and Changulani et al.12The results in this aspect i.e. function of shoulder and elbow joints are comparable with those of Vander Griend et al, Heim et al and Haveri et al that are 83.33%,87.3% and 91% good function of shoulder and elbowm, respectively.