***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Terrible triad injury ( TTI ) , one of the main patterns of complex elbow instability , is difficult to treat and yields conflicting surgical results . We analyzed prospect ively a series of patient affected by TTI and treated according to the current diagnostic and surgical protocol s to investigate whether their application allow to obtain more predictable outcomes . MATERIAL AND METHODS We analyzed 26 patients with a mean age of 52 years .  Preoperative X-rays and CT were performed ; all patients were operated by the same elbow surgeon and underwent the same surgical and rehabilitation treatment . Final functional outcome was assessed by the Mayo Elbow Performance Score ( MEPS ) , Quick-Disability of the Arm Shoulder and H and -score ( Q-DASH ) and the modified-American Shoulder and Elbow Surgeons score ( m-Ases ) . A radiographic evaluation  was also performed . RESULTS Mean follow-up was 31 months . At final evaluation , mean flexion , extension , supination and pronation were 137 ° , 10 ° , 77 ° and 79 ° , respectively ; mean MEPS , m-ASES and Q-DASH scores were respectively 96 , 91 and 8 points . Complications observed after first surgery were : elbow stiffness in 5 cases , mild posterolateral instability in 3 cases , chronic subluxation in 1 case . Radiographic evaluation showed secondary arthritis in 9 cases , symptomatic HO in 3 cases and late hardware displacement in 2 cases . Six out of 26 patient underwent reoperation with final satisfactory results . CONCLUSION The current diagnostic and therapeutic protocol s allow obtaining satisfactory clinical outcomes in majority of cases but a high number of major and minor unpredictable complications persist yet . In this series , low compliance , obesity , and extensive soft elbow tissue damage caused by high-energy trauma represented negative prognostic factors unrelated to surgery . On the other h and , the strict application of current algorithms by an expert elbow surgeon appears to improve clinical results by reducing the influence of other avoidable negative prognostic factors well known in current literature , such as the incomplete recognition of injuries , delayed treatment , inadequate treatment of bony and ligamentous injuries , prolonged immobilization and , last but not least , the surgeon 's inexperience . LEVEL OF EVIDENCE Level IV , Case series , Treatment study Complex fracture-dislocations of the elbow can often be either irreducible or unstable , with an inability to hold the reduction or with the delayed development of subluxation or dislocation . The aim of the present study was to evaluate the etiology of the instability , both osseous and ligamentous , and the results of stabilization with a combination of internal fixation , ligament repair , radial head arthroplasty and , when necessary , hinged external fixation . Figures 1 and 2 represent our formulated protocol and treatment algorithm for elbow fracture-dislocation in this series of thirty-two patients . Fig. 1 Constellation of the “ terrible triad ” injury and the anatomic structures encountered . LUCL = lateral ulnar collateral ligament , and MUCL = medial ulnar collateral ligament . The so-called terrible triad injury has a history of complicated outcomes as the surgeon attempts to maximize functional range-of-motion goals while maintaining stability1 - 3 . On the basis of previous evaluations of these specific injuries and the recent evolution of surgical protocol s , the restoration of congruency and stability coupled with progressive rehabilitation can reliably enhance the functional outcome 4 - 6 . Thirty-two consecutive patients with unstable elbow injuries who had been referred to three tertiary centers were prospect ively recruited for the present study between 2001 and 2005 . Six of these patients had been unsuccessfully managed at outside facilities and had been transferred to our care . The unsuccessful treatments had included attempted closed reduction ( four patients ) , radial head excision ( one patient ) , and open reduction and internal fixation of the proximal part of the ulna ( one patient ) . Fig. 2 Treatment algorithm proposed for the achievement of anatomic fixation and mechanical stability in patients with complex fracture-dislocations of the elbow . EUA = examination under anesthesia , MUCL = medial ulnar collateral ligament , LUCL = lateral ulnar collateral ligament , P/L = posterolateral stability , and ORIF = open reduction and internal fixation . All 
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Similarly , there was no statistically significant difference demonstrated between the REP and REC groups in terms of ROM .
Conclusions Comparable results with good outcomes in terms of functional scores and ROM can be achieved with both REP and REC when treating TTIE , although the re-operation rate for both remains relatively high .
Given there is no apparent clear advantage between the two treatment groups , we would suggest that REC should be performed when a satisfactory fixation can be achieved as the longevity of REP in young patients with a TTIE is currently uncertain