There continues to be debate about whether intra-articular fractures of the tibial plateau doom patients to poor outcomes and PTA. Ostrum stated that many lateral tibial plateau fractures do not progress to severe PTA or total knee arthroplasty [1]. Ostrum stated that the “literature does not support the belief that an intra-articular tibial plateau fracture will progress to arthritis” [1]. What are the factors that contribute to clinical outcomes, PTA, and the need for TKA after intra-articular tibial plateau fracture? We first discuss the role of articular step-off (articular reduction).

Dirschl et al. stated that articular incongruity was well-tolerated after tibial plateau fractures [16]. He noted that there is “little support in the literature for the assertion that accurate reduction of tibial plateau fractures, particularly to tolerances <2 mm, is critical for a good clinical outcome” [16].

Giannoudis et al. noted that articular incongruities were well-tolerated for tibial plateau fractures [4]. These authors noted that other factors only partially related to articular reduction (e.g., joint stability, retention of the meniscus, and coronal plane alignment) were more important in determining outcome than articular step-off alone [4]. Of the 11 studies reviewed, 5 showed no effect on the outcome comparing articular step-off and no step-off [17–20]. Of the other six studies, one showed acceptable results with step-off <10 mm [21] and another study showed inferior results with step-off >10 mm [22].

Lower tolerances for articular step-off were reported in the two other studies: one showed satisfactory results for <4 mm displacement with conservative treatment [23], and another showed that increased articular step-off heights progressively increased valgus angulation and maximum contact pressure was apparent at more than 4 mm step-off [24]. Another study noted that operative stabilization should be based on knee stability in full extension and not on roentgenographic criteria [25]. Blokker et al. noted that the adequacy of reduction is the most important factor in predicting outcomes of operative treatment with a residual step-off more than 5 mm was associated with an unsatisfactory result [26]. Wilde stated that preserving the normal alignment of the knee was critical to the end result of the treatment of tibial plateau fractures [27]. He further noted, “Joint depression, per se, if not associated with malalignment, does not necessarily cause poor results” [27]. In terms of the effect of joint stability, he noted that joint depression in a stable knee was not necessarily associated with a poor result, but depression more than 4 mm did have an effect on outcome [27].

Articular step-off after intra-articular fractures of the tibial plateau is less of a determinant of outcome, particularly when the step-offs are small (≤4 mm) and the fracture involves mainly the lateral tibial plateau.

Dirschl noted that the tibial plateau has thicker articular cartilage than many other joints [16], and that the effect of factors other than articular reduction such as knee instability, malalignment, and meniscectomy were more important to the outcome [16]. Ostrum also noted that certain plateau fractures (e.g., medial tibial plateau fractures and those having had an excision of the meniscus) have a much poorer prognosis [1].

Rademakers et al. reported a 31 % incidence of radiographic arthritis after operatively treated tibial plateau fractures at 14 years, but most were asymptomatic [28]. However, results were much worse with malalignment >5°. Twenty-seven percent of patients reported moderate to severe symptoms [28].

Multiple studies demonstrate poorer clinical, radiographic, and functional outcome scores with increasing fracture classification number using the Schatzker classification [29–31]. Prasad et al. reviewed 40 Schatzker type V and VI tibial plateau fractures treated with dual plating with 4 years follow-up [32]. All patients had final radiographic articular step-off <2 mm, good coronal and sagittal plane alignment, and mean condylar width was <5 mm. Final clinical outcome was assessed by the Oxford Knee Score with 32 of 40 with a final score >30 (excellent) and only eight patients with a score between 20 and 29 good.

The AO Classification of tibial plateau fractures did not correlate well with outcome. According to Jansen et al. 30.4 % of 23 type C (AO/OTA classification) fractures demonstrated no signs of PTA and 39.1 % had prominent arthritic changes at 67 months [33]. At the final follow up, 90.9 % (20 patients) achieved a good to excellent range of motion (full extension and flexion >110°) with mean flexion of 124.9°. The average Lysholm score was 66.2 points (out of 100). A varus/valgus malalignment >3° resulted in significantly lower outcome scores; however, there was no correlation with the onset of post-traumatic arthritis (Kellgren score).

Ehlinger et al. reviewed 13 patients who were surgically treated for a Schatzker IV–VI tibial plateau fracture after a mean follow-up of 39.1 months [34]. The average Lysholm score was 94.1, mean HSS score was 93.6, and all patients previously employed returned to work after 4.5 months [34]. Five patients were noted to have an articular step-off >2 mm, yet all 13 patients demonstrated no radiographic evidence of osteoarthritis at final evaluation [34].

The magnitude of the energy at the time of injury may be important in determining outcomes after intra-articular tibial plateau fractures. When reviewing the treatment of open high-energy tibial plateau fractures with significant soft tissue injury treated with modified hybrid external fixator, Ariffin et al. found 15 of 33 patients (48 %) to have an excellent Rasmussen knee functional score at 12 months postoperatively, 13 (42 %) patients had a good score (20–26) and 3 (10 %) had a fair score (10–19) [35]. The mean Lysholm score following higher energy fracture patterns varied from 66.2 to 94.1. Malalignment and articular step-off >2 mm may contribute significantly to the development of post-traumatic arthritis and poorer clinical outcomes after tibial plateau fracture.

Various surgical approaches to tibial plateau fractures appear to have a relationship with clinical outcome and the onset of PTA. Solomon et al. retrospectively reviewed 17 patients assessing fracture reduction and maintenance following direct posterolateral transfibular approach (9 patients) or an indirect anterolateral approach (8 patients) for unicondylar posterolateral tibial plateau fractures with a 2-year follow-up [36]. Radiographically, all nine patients who underwent the direct posterolateral transfibular approach were reduced anatomically (i.e., step-off <2 mm, condylar widening <5 mm, and a medial proximal tibial angle (MPTA) within normal range). In contrast, the anterolateral approach leads to an average step-off of 5.5 mm postoperatively, which progressed to an average of 6.0 mm in six of eight patients at the 2-year follow-up. At 2-year follow-up, the Lysholm scores were significantly higher in those treated through a direct approach when compared to the indirect anterolateral approach. Again, this data supports the idea that malreduction and increased articular step-off results in poorer clinical outcome.

Dall’Oca et al. reviewed 100 patients, and compared arthroscopically assisted reduction and internal fixation (group A) with open reduction and internal fixation (group B) [29]. One patient developed lateral compartment arthritis with residual valgus at 1 year resulting in a unilateral knee prosthesis. In addition, only two patients in group B (ORIF) developed symptomatic arthritic changes resulting in significant post-traumatic valgus deformity treated with TKA. Clinical outcomes assessed by Rasmussen and HSS scores were 27.62 and 76.36, respectively, for those treated with arthroscopically assisted fixation. With regard to the classic ORIF treatment group, the scores were 26.81 and 73.12, respectively. No significant difference was identified between the clinical outcome scores for arthroscopically assisted versus ORIF. Arthroscopically assisted internal fixation is a valid treatment option.

Siegler et al. examined the clinical outcomes of 27 arthroscopically assisted percutaneous fixation for Schatzker I–III fractures with a mean follow-up of 59.5 months noting a mean Lysholm score of 86 and a mean Rasmussen clinical score of 25.5 (maximum score of 30) [37]. On radiographic evaluation, 47.6 % presented with early arthritic changes.

Malakasi et al. investigated 60 tibial plateau fractures with either ORIF (30 patients) or hybrid external fixation (30 patients) for 12 months noting no significant differences with regard to functional or radiographic outcomes [31]. Poorer clinical and radiographic outcomes correlated with increasing Schatzker classification.

Biggi et al. reported no radiographic evidence of arthritic changes in 41 of 47 patients (87 %) after a mean 18 months following a minimally invasive percutaneous osteosynthesis (MIPO) technique of internal fixation for a tibial plateau fracture [38]. The Rasmussen functional score was 27 at 1 year postoperatively. Chan et al. noted a mean clinical Rasmussen score of 28.4 and 19 % (10 of 54) demonstrated post-traumatic arthritis radiographically when reviewing arthroscopically assisted fixation of tibial plateau fractures at a mean follow-up of 87 months [39]. Bicondylar fractures reported poorer clinical outcomes; yet the numbers were not statistically significant in comparison to unicondylar fracture patterns. The rate of arthritic changes ranges from 19 to 47.6 % with an average good to excellent Rasmussen clinical outcome scores and Knee Society Scores.

Loibl et al. studied the rate of return to sporting activities, an excellent indicator of functional outcome, following internal fixation of a tibial plateau fracture with the responses of 103 patients after a mean of 7.8 years [40]. Eight-eight percent of patients were participating in sports at the time of the survey with no change in the frequency or duration of activity; however, an increase in low-impact activities was noted (i.e., walking, fitness/weight training, water aerobics). More severe fracture patterns, specifically B3 and C3 fractures, were associated with poorer clinical functional scores and decreased rates of return to sports.

According to Kraus et al., 73 % of 89 patients were participating in sporting activities at an average of 52.8 months postoperatively following a tibial plateau fracture, with 88.8 % participating in sports at the time of injury, a 15.8 % reduction [30]. Of the 11 highly competitive athletes, only two returned to the same level of competition at the time of the survey. These authors noted a significant decline in the number of sporting activities and the frequency of activity per week [30]. The Lysholm score averaged 76.6. Higher-energy fracture patterns (i.e., Schatzker IV–VI) reported significantly poorer clinical outcome scores.

Because articular step-offs of the tibial plateau are well-tolerated, non-articular step-off fractures seem to be more important factors in determining outcome for the fractured tibial plateau. We have summarized the factors that influence patient outcomes positively and those that influence outcomes negatively (Table 21.2). Finally, what are the variables and risk factors associated with the need for arthroplasty after tibial plateau fractures?

The need for total knee arthroplasty after tibial plateau fracture may be low; but when performed, the complication rate is high [1, 41, 42].

Risk factors for total knee arthroplasty (TKA) after plateau fracture have been reported to be age over 48, bicondylar fractures, and comorbidities [43].

Prior ORIF for a tibial plateau fracture significantly changes the clinical outcome of TKA. Saleh et al. analyzed the outcome of 15 patients who underwent TKA after ORIF of a tibial plateau fracture [41]. They found a high rate of infection (three patients had one), patella tendon disruption (two patients), and postoperative secondary procedures (three patients who required closed manipulation). They concluded that TKA after ORIF of a tibial plateau fracture decreased pain and improved function, but is technically demanding and is associated with a high failure rate (5 of 15) [41].

Weiss et al. also reported a high postoperative complication rate (26 %) and a high reoperation rate (21 %) associated with TKA after tibial plateau fracture [42]. Wasserstein et al. reported that 10 years after tibial plateau fracture surgery, 7.3 % of patients had undergone a TKA [43]. They noted that this was a 5.3 times increased likelihood compared to the general population [43]. They also noted that older age, higher comorbidity, and bicondylar fractures were all associated with an increased risk of future TKA [43].

The rate of post-traumatic arthritic changes following tibial plateau changes varies widely from 19 to 48 % at a mean of 2 years postoperatively; 10-year Kaplan–Meier survivorship is 96 % (i.e., 96 % of patients will not undergo a reconstructive procedure for post-traumatic arthritis at 10 years after plateau fracture). In summary, it appears that radiographic arthritic changes may not correlate with the need for TKA after a tibial plateau fracture. Furthermore, TKA after tibial plateau fracture is associated with both higher complication rates and higher failure rates.

Historic literature reported a high rate of PTA on radiographic evaluation after an intra-articular distal radius fracture. Articular incongruity >2 mm significantly increased the rate of arthritic development (50–100 %) [44–48]. Knirk and Jupiter observed 65 % of 43 fractures developed radiographic PTA with the following breakdown various treatments: casting, 21 of 43 had PTA; percutaneous pinning, 17 of 43 had PTA; external fixation, 2 of 43 had PTA; and ORIF, 3 of 43 had PTA. Articular incongruity was the most critical factor in the development of arthrosis [47]. Ninety-one percent of the patients who healed with an articular step-off developed arthritis, but only 11 % in those with a congruous joint developed arthrosis. Bradway et al. further reiterated the impact of step-off on the development of arthritic changes radiographically, noting 100 % (4 of 4) developed PTA in patients with a step-off >2 mm after a mean follow up of 4.8 years, and only 25 % (3 of 12) in those with incongruity <2 mm [44]. Biologically, this radiographic development is confirmed with significantly increased intra-articular contact pressures in the lunate fossa with scaphoid fossa depressions as small as 1 mm in all loading positions of the wrist [49].

The clinical impact of arthritic changes following articular incongruity of 1–2 mm remains unclear. Strange-Vognsen identified 42 patients who sustained an intra-articular fracture and reexamined them after an average of 16 years (2–26) noting >50 % demonstrated radiographic changes consistent with arthrosis [48]. Although subjective patient outcomes correlated with deformity and arthrosis, they did not correlate with intra-articular step-off [48]. Forward et al. reevaluated 106 intra-articular fractures after an average of 38 years (33–42) observing 68 % of the patients had developed radiographic arthritic changes; yet the DASH scores were unchanged from population norms, and patient function as assessed by Patient Evaluation Measure (PEM) was impaired by <10 % [46]. Further, Catalano et al. reported a 76 % rate of arthritic radiographic changes in 21 patients after an average of 7.1 years [45]. The authors also noted a significant correlation with residual displacement of articular fragments and the development of arthrosis; however, functional and clinical outcomes did not correlate with radiographic findings, specifically gap formation or articular incongruity. All patients reported a good to excellent functional outcome irrespective of radiographic evaluation [45].

Giannoudis et al. analyzed the effect of articular step-off on the outcome of intra-articular fractures of the distal radius in ten studies (two biomechanical studies and eight clinical studies) [4]. Two studies used a 1 mm step-off with one of these studies noting acceptable results with a step-off of <1 mm [50] and the other reporting no radiographic evidence of PTA in fractures that healed with a step-off of up to 1 mm [51]. Six studies utilized a 2 mm threshold which was associated with the best outcomes [45, 52–56]. In two studies, the best outcomes were noted when the reduction step-off was within 2 mm [44, 47]. In two other studies, worse outcomes occurred when the step-off exceeded 2 mm [54, 56]. PTA was noted with a step-off/articular incongruity of more than 2 mm in two additional studies [45, 55]. Two more studies reported a 3 mm tolerance with two biomechanical studies reporting increased radiocarpal stresses with a step-off of 3 mm [52, 53].

Dirschl et al. stated that radiographic changes consistent with PTA of the radiocarpal joint after fracture “may be well tolerated clinically, causing few symptoms and little impairment, at least during the first several years after injury” [17]. These authors further questioned “whether clinical results will deteriorate at longer follow-up and whether deterioration is correlated with greater step-off or gap deformities at the time of union.” [17]

Mignemi et al. assessed the ability of volar locked plating to achieve normal radiographic parameters in 185 distal radius fractures [57]. Volar locked plating achieved an articular step-off <2 mm in most fractures, but only restored normal measurements for volar tilt, radial inclination, and ulnar variance in 50 % of the patients [57]. In addition, these authors noted that the ability of volar locked plating to restore and maintain ulnar variance and volar tilt decreased with more complex intra-articular types [57].

Imperfect reductions may not result in symptomatic long-term arthritis. The clinical implications of PTA following an intra-articular distal radius fracture remain unclear. Further long-term studies investigating the impact of radiographic arthrosis on functional and clinical outcomes are needed.

Variables other than articular step-off and their effect on outcome are important. Amorosa et al. studied the subjective functional outcomes of patients who were at least 70 years of age who had sustained distal radius fractures [58]. They used the DASH and SF-8 surveys and examined radiographic parameters such as articular step-off, dorsal tilt, ulnar variance, and the presence/absence of an ulnar styloid fracture. They found that the only radiographic parameter that affected functional outcome was an associated ulnar styloid fracture [58]. Females had worse outcomes than males [58]. Paksima et al. assessed 335 patients to evaluate the association of patient education level on pain and disability after distal radius fracture [59]. They found that each increase in the level of education (as in from high school to college) corresponded to a 2 to 1 rate of improvement over time [59].

How do various treatment options, including closed reduction and casting/immobilization with or without percutaneous pinning, external fixation with or without percutaneous pinning, and internal fixation, influence patient outcomes? Williksen et al. performed a randomized study of 107 unstable distal radius fractures treated with external fixation with adjuvant pins versus volar locking plate fixation and followed for 1 year [60]. The volar plate group demonstrated a statistically significantly higher Mayo score (90 vs. 85, measured out of 100), better supination (89 vs. 85 degree), and less radial shortening (+1.4 vs. +2.2 mm). For complete articular fractures, volar plating demonstrated statistically significant improvements in supination (90 vs. 76) and less radial shortening (+1.1 vs. +2.8 mm). Of note, the QuickDASH score was not significantly different between the groups.

Karantana et al. piloted a randomized controlled trial focusing on outcomes of distal radius fractures treated with closed reduction and percutaneous fixation (with or without a bridging external fixator) versus volar locking plate in 130 patients followed for 1-year postoperatively [61]. Patients who were treated with volar locking plates had significantly better Patient Evaluation Measure (PEM) scores, QuickDASH scores, and range of motion at 6 weeks; however, no significant differences were identified at 12 weeks or 1 year. Multiple meta-analyses conclude that volar locking plates are significantly better with regards to DASH scores, volar tilt, and fewer complications (mainly infection) [62–66].